New native transport for kqueue

Motivation:
We currently don't have a native transport which supports kqueue https://www.freebsd.org/cgi/man.cgi?query=kqueue&sektion=2. This can be useful for BSD systems such as MacOS to take advantage of native features, and provide feature parity with the Linux native transport.

Modifications:
- Make a new transport-native-unix-common module with all the java classes and JNI code for generic unix items. This module will build a static library for each unix platform, and included in the dynamic libraries used for JNI (e.g. transport-native-epoll, and eventually kqueue).
- Make a new transport-native-unix-common-tests module where the tests for the transport-native-unix-common module will live. This is so each unix platform can inherit from these test and ensure they pass.
- Add a new transport-native-kqueue module which uses JNI to directly interact with kqueue

Result:
JNI support for kqueue.
Fixes https://github.com/netty/netty/issues/2448
Fixes https://github.com/netty/netty/issues/4231

all/pom.xml

@@ -36,7 +36,11 @@
   <profiles>
     <profile>
       <id>full</id>
-
+      <activation>
+        <property>
+          <name>uber</name>
+        </property>
+      </activation>
       <!-- Only include in full profile as this will not work on Java9 yet -->
       <!-- https://issues.apache.org/jira/browse/JXR-133 -->
       <build>
@@ -162,25 +166,6 @@
         </plugins>
       </build>
     </profile>
-    <profile>
-      <id>linux</id>
-      <activation>
-        <os>
-          <family>linux</family>
-        </os>
-      </activation>
-      <dependencies>
-        <!-- All release modules -->
-        <dependency>
-          <groupId>${project.groupId}</groupId>
-          <artifactId>netty-transport-native-epoll</artifactId>
-          <version>${project.version}</version>
-          <classifier>${epoll.classifier}</classifier>
-          <scope>compile</scope>
-          <optional>true</optional>
-        </dependency>
-      </dependencies>
-    </profile>
   </profiles>
 
   <dependencies>
@@ -347,6 +332,22 @@
       <scope>compile</scope>
       <optional>true</optional>
     </dependency>
+    <dependency>
+      <groupId>${project.groupId}</groupId>
+      <artifactId>netty-transport-native-epoll</artifactId>
+      <version>${project.version}</version>
+      <classifier>linux-x86_64</classifier>
+      <scope>compile</scope>
+      <optional>true</optional>
+    </dependency>
+    <dependency>
+      <groupId>${project.groupId}</groupId>
+      <artifactId>netty-transport-native-kqueue</artifactId>
+      <version>${project.version}</version>
+      <classifier>osx-x86_64</classifier>
+      <scope>compile</scope>
+      <optional>true</optional>
+    </dependency>
 
     <!-- Add optional dependencies explicitly to avoid Javadoc warnings and errors. -->
     <dependency>
@@ -429,7 +430,7 @@
               <goal>unpack-dependencies</goal>
             </goals>
             <configuration>
-              <excludes>io/netty/example/**,META-INF/native/libnetty-tcnative*</excludes>
+              <excludes>io/netty/example/**,META-INF/native/libnetty-tcnative*,META-INF/native/include/**,META-INF/native/**/*.a</excludes>
               <includes>io/netty/**,META-INF/native/**</includes>
               <includeScope>runtime</includeScope>
               <includeGroupIds>${project.groupId}</includeGroupIds>

common/src/main/java/io/netty/util/NetUtil.java

@@ -24,6 +24,9 @@ import io.netty.util.internal.logging.InternalLoggerFactory;
 import java.io.BufferedReader;
 import java.io.File;
 import java.io.FileReader;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.InputStreamReader;
 import java.net.Inet4Address;
 import java.net.Inet6Address;
 import java.net.InetAddress;
@@ -271,12 +274,27 @@ public final class NetUtil {
                             logger.debug("{}: {}", file, somaxconn);
                         }
                     } else {
-                        if (logger.isDebugEnabled()) {
+                        // Try to get from sysctl
-                            logger.debug("{}: {} (non-existent)", file, somaxconn);
+                        Integer tmp = null;
+                        if (SystemPropertyUtil.getBoolean("io.netty.net.somaxconn.trySysctl", false)) {
+                            tmp = sysctlGetInt("kern.ipc.somaxconn");
+                            if (tmp == null) {
+                                tmp = sysctlGetInt("kern.ipc.soacceptqueue");
+                                if (tmp != null) {
+                                    somaxconn = tmp;
+                                }
+                            } else {
+                                somaxconn = tmp;
+                            }
+                        }
+
+                        if (tmp == null) {
+                            logger.debug("Failed to get SOMAXCONN from sysctl and file {}. Default: {}", file,
+                                         somaxconn);
                         }
                     }
                 } catch (Exception e) {
-                    logger.debug("Failed to get SOMAXCONN from: {}", file, e);
+                    logger.debug("Failed to get SOMAXCONN from sysctl and file {}. Default: {}", file, somaxconn, e);
                 } finally {
                     if (in != null) {
                         try {
@@ -291,6 +309,38 @@ public final class NetUtil {
         });
     }
 
+    /**
+     * This will execute <a href ="https://www.freebsd.org/cgi/man.cgi?sysctl(8)">sysctl</a> with the {@code sysctlKey}
+     * which is expected to return the numeric value for for {@code sysctlKey}.
+     * @param sysctlKey The key which the return value corresponds to.
+     * @return The <a href ="https://www.freebsd.org/cgi/man.cgi?sysctl(8)">sysctl</a> value for {@code sysctlKey}.
+     */
+    private static Integer sysctlGetInt(String sysctlKey) throws IOException {
+        Process process = new ProcessBuilder("sysctl", sysctlKey).start();
+        try {
+            InputStream is = process.getInputStream();
+            InputStreamReader isr = new InputStreamReader(is);
+            BufferedReader br = new BufferedReader(isr);
+            try {
+                String line = br.readLine();
+                if (line.startsWith(sysctlKey)) {
+                    for (int i = line.length() - 1; i > sysctlKey.length(); --i) {
+                        if (!Character.isDigit(line.charAt(i))) {
+                            return Integer.valueOf(line.substring(i + 1, line.length()));
+                        }
+                    }
+                }
+                return null;
+            } finally {
+                br.close();
+            }
+        } finally {
+            if (process != null) {
+                process.destroy();
+            }
+        }
+    }
+
     /**
      * Returns {@code true} if IPv4 should be used even if the system supports both IPv4 and IPv6. Setting this
      * property to {@code true} will disable IPv6 support. The default value of this property is {@code false}.

common/src/main/java/io/netty/util/internal/EmptyArrays.java

@@ -24,6 +24,7 @@ import java.security.cert.X509Certificate;
 
 public final class EmptyArrays {
 
+    public static final int[] EMPTY_INTS = {};
     public static final byte[] EMPTY_BYTES = {};
     public static final char[] EMPTY_CHARS = {};
     public static final Object[] EMPTY_OBJECTS = {};

common/src/main/java/io/netty/util/internal/PlatformDependent.java

@@ -287,6 +287,10 @@ public final class PlatformDependent {
         PlatformDependent0.freeMemory(address);
     }
 
+    public static long reallocateMemory(long address, long newSize) {
+        return PlatformDependent0.reallocateMemory(address, newSize);
+    }
+
     /**
      * Raises an exception bypassing compiler checks for checked exceptions.
      */

common/src/main/java/io/netty/util/internal/PlatformDependent0.java

@@ -752,6 +752,10 @@ final class PlatformDependent0 {
         UNSAFE.freeMemory(address);
     }
 
+    static long reallocateMemory(long address, long newSize) {
+        return UNSAFE.reallocateMemory(address, newSize);
+    }
+
     private PlatformDependent0() {
     }
 }

microbench/pom.xml

@@ -51,7 +51,7 @@
           <groupId>${project.groupId}</groupId>
           <artifactId>netty-transport-native-epoll</artifactId>
           <version>${project.version}</version>
-          <classifier>${epoll.classifier}</classifier>
+          <classifier>${jni.classifier}</classifier>
         </dependency>
       </dependencies>
       <build>

pom.xml

@@ -146,55 +146,72 @@
         </os>
       </activation>
       <modules>
+        <module>transport-native-unix-common-tests</module>
+        <module>transport-native-unix-common</module>
         <module>transport-native-epoll</module>
       </modules>
     </profile>
-    <!--
-      Netty must be released from RHEL 6.8 x86_64 or compatible so that:
-
-        1) we ship x86_64 version of epoll transport officially, and
-        2) we ensure the ABI compatibility with older GLIBC versions.
-
-           The shared library built on a distribution with newer GLIBC
-           will not run on older distributions.
-    -->
     <profile>
-      <id>restricted-release</id>
+      <id>mac</id>
-      <build>
+      <activation>
-        <plugins>
+        <os>
-          <plugin>
+          <family>mac</family>
-            <artifactId>maven-enforcer-plugin</artifactId>
+        </os>
-            <executions>
+      </activation>
-              <execution>
+      <modules>
-                <id>enforce-release-environment</id>
+        <module>transport-native-unix-common-tests</module>
-                <goals>
+        <module>transport-native-unix-common</module>
-                  <goal>enforce</goal>
+        <module>transport-native-kqueue</module>
-                </goals>
+      </modules>
-                <configuration>
+    </profile>
-                  <rules>
+    <profile>
-                    <requireProperty>
+      <id>freebsd</id>
-                      <regexMessage>
+      <activation>
-                        Release process must be performed on linux-x86_64.
+        <os>
-                      </regexMessage>
+          <family>unix</family>
-                      <property>os.detected.classifier</property>
+          <name>freebsd</name>
-                      <regex>^linux-x86_64$</regex>
+        </os>
-                    </requireProperty>
+      </activation>
-                    <requireFilesContent>
+      <modules>
-                      <message>
+        <module>transport-native-unix-common-tests</module>
-                        Release process must be performed on RHEL 6.8 or its derivatives.
+        <module>transport-native-unix-common</module>
-                      </message>
+        <module>transport-native-kqueue</module>
-                      <files>
+      </modules>
-                        <file>/etc/redhat-release</file>
+    </profile>
-                      </files>
+    <profile>
-                      <content>release 6.8</content>
+      <id>openbsd</id>
-                    </requireFilesContent>
+      <activation>
-                  </rules>
+        <os>
-                </configuration>
+          <family>unix</family>
-              </execution>
+          <name>openbsd</name>
-            </executions>
+        </os>
-          </plugin>
+      </activation>
-        </plugins>
+      <modules>
-      </build>
+        <module>transport-native-unix-common-tests</module>
+        <module>transport-native-unix-common</module>
+        <module>transport-native-kqueue</module>
+      </modules>
+    </profile>
+    <!-- The uber artifacts depend on artifacts built from different platforms and will fail if these artifacts are not
+         available. Typically we only build the uber jars as part of the release process so the build sequencing
+         is controlled and can be sequenced correctly. For example we may do the following:
+
+         <from a linux machine>
+         $ mvn release
+         <after this completes log onto a MacOS machine, note fail-at-end, and -D to activate multiple profiles>
+         $ mvn release -fae -Duber
+      -->
+    <profile>
+      <id>uber</id>
+      <activation>
+        <property>
+          <name>uber</name>
+        </property>
+      </activation>
+      <modules>
+        <module>all</module>
+        <module>tarball</module>
+      </modules>
     </profile>
     <profile>
       <!--
@@ -252,7 +269,7 @@
     <conscrypt.artifactId>conscrypt-openjdk-uber</conscrypt.artifactId>
     <conscrypt.version>1.0.0.RC7</conscrypt.version>
     <conscrypt.classifier />
-    <epoll.classifier>${os.detected.name}-${os.detected.arch}</epoll.classifier>
+    <jni.classifier>${os.detected.name}-${os.detected.arch}</jni.classifier>
     <logging.config>${project.basedir}/../common/src/test/resources/logback-test.xml</logging.config>
     <logging.logLevel>debug</logging.logLevel>
     <log4j2.version>2.6.2</log4j2.version>
@@ -291,9 +308,7 @@
     <module>testsuite-autobahn</module>
     <module>testsuite-osgi</module>
     <module>microbench</module>
-    <module>all</module>
     <module>bom</module>
-    <module>tarball</module>
   </modules>
 
   <dependencyManagement>
@@ -979,7 +994,7 @@
         <version>2.5.3</version>
         <configuration>
           <useReleaseProfile>false</useReleaseProfile>
-          <arguments>-P restricted-release,sonatype-oss-release,full</arguments>
+          <arguments>-P restricted-release,sonatype-oss-release</arguments>
           <autoVersionSubmodules>true</autoVersionSubmodules>
           <allowTimestampedSnapshots>false</allowTimestampedSnapshots>
           <tagNameFormat>netty-@{project.version}</tagNameFormat>
@@ -1110,18 +1125,6 @@
 
     <pluginManagement>
       <plugins>
-        <plugin>
-          <artifactId>maven-enforcer-plugin</artifactId>
-          <version>1.4.1</version>
-          <dependencies>
-            <!-- Provides the 'requireFilesContent' enforcer rule. -->
-            <dependency>
-              <groupId>com.ceilfors.maven.plugin</groupId>
-              <artifactId>enforcer-rules</artifactId>
-              <version>1.2.0</version>
-            </dependency>
-          </dependencies>
-        </plugin>
         <!-- keep surefire and failsafe in sync -->
         <plugin>
           <artifactId>maven-surefire-plugin</artifactId>

tarball/pom.xml

@@ -96,6 +96,11 @@
   <profiles>
     <profile>
       <id>full</id>
+      <activation>
+        <property>
+          <name>uber</name>
+        </property>
+      </activation>
       <build>
         <plugins>
           <plugin>

testsuite/src/main/java/io/netty/testsuite/transport/socket/SocketShutdownOutputBySelfTest.java

@@ -30,7 +30,10 @@ import java.nio.channels.ClosedChannelException;
 import java.util.concurrent.BlockingQueue;
 import java.util.concurrent.LinkedBlockingQueue;
 
-import static org.junit.Assert.*;
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.fail;
 
 public class SocketShutdownOutputBySelfTest extends AbstractClientSocketTest {
 
@@ -43,9 +46,10 @@ public class SocketShutdownOutputBySelfTest extends AbstractClientSocketTest {
         TestHandler h = new TestHandler();
         ServerSocket ss = new ServerSocket();
         Socket s = null;
+        SocketChannel ch = null;
         try {
             ss.bind(addr);
-            SocketChannel ch = (SocketChannel) cb.handler(h).connect().sync().channel();
+            ch = (SocketChannel) cb.handler(h).connect().sync().channel();
             assertTrue(ch.isActive());
             assertFalse(ch.isOutputShutdown());
 
@@ -68,12 +72,15 @@ public class SocketShutdownOutputBySelfTest extends AbstractClientSocketTest {
             assertTrue(h.ch.isOutputShutdown());
 
             // If half-closed, the peer should be able to write something.
-            s.getOutputStream().write(1);
+            s.getOutputStream().write(new byte[] { 1 });
             assertEquals(1, (int) h.queue.take());
         } finally {
             if (s != null) {
                 s.close();
             }
+            if (ch != null) {
+                ch.close();
+            }
             ss.close();
         }
     }

transport-native-epoll/pom.xml

@@ -27,11 +27,81 @@
   <packaging>jar</packaging>
 
   <properties>
-    <jni.compiler.args.ldflags>LDFLAGS=-Wl,--no-as-needed -lrt</jni.compiler.args.ldflags>
     <!-- Needed by the native transport as we need the memoryAddress of the ByteBuffer -->
     <argLine.java9.extras>--add-exports java.base/sun.security.x509=ALL-UNNAMED --add-opens=java.base/java.nio=ALL-UNNAMED</argLine.java9.extras>
+    <unix.common.lib.name>netty-unix-common</unix.common.lib.name>
+    <unix.common.lib.dir>${project.build.directory}/unix-common-lib</unix.common.lib.dir>
+    <unix.common.lib.unpacked.dir>${unix.common.lib.dir}/META-INF/native/lib</unix.common.lib.unpacked.dir>
+    <unix.common.include.unpacked.dir>${unix.common.lib.dir}/META-INF/native/include</unix.common.include.unpacked.dir>
+    <jni.compiler.args.ldflags>LDFLAGS=-L${unix.common.lib.unpacked.dir} -Wl,--no-as-needed -lrt -Wl,--whole-archive -l${unix.common.lib.name} -Wl,--no-whole-archive</jni.compiler.args.ldflags>
   </properties>
 
+  <profiles>
+    <!--
+      Netty must be released from RHEL 6.8 x86_64 or compatible so that:
+
+        1) we ship x86_64 version of epoll transport officially, and
+        2) we ensure the ABI compatibility with older GLIBC versions.
+
+           The shared library built on a distribution with newer GLIBC
+           will not run on older distributions.
+    -->
+    <profile>
+      <id>restricted-release-epoll</id>
+      <build>
+        <pluginManagement>
+          <plugins>
+            <plugin>
+              <artifactId>maven-enforcer-plugin</artifactId>
+              <version>1.4.1</version>
+              <dependencies>
+                <!-- Provides the 'requireFilesContent' enforcer rule. -->
+                <dependency>
+                  <groupId>com.ceilfors.maven.plugin</groupId>
+                  <artifactId>enforcer-rules</artifactId>
+                  <version>1.2.0</version>
+                </dependency>
+              </dependencies>
+            </plugin>
+          </plugins>
+        </pluginManagement>
+        <plugins>
+          <plugin>
+            <artifactId>maven-enforcer-plugin</artifactId>
+            <executions>
+              <execution>
+                <id>enforce-release-environment</id>
+                <goals>
+                  <goal>enforce</goal>
+                </goals>
+                <configuration>
+                  <rules>
+                    <requireProperty>
+                      <regexMessage>
+                        Release process must be performed on linux-x86_64.
+                      </regexMessage>
+                      <property>os.detected.classifier</property>
+                      <regex>^linux-x86_64$</regex>
+                    </requireProperty>
+                    <requireFilesContent>
+                      <message>
+                        Release process must be performed on RHEL 6.8 or its derivatives.
+                      </message>
+                      <files>
+                        <file>/etc/redhat-release</file>
+                      </files>
+                      <content>release 6.8</content>
+                    </requireFilesContent>
+                  </rules>
+                </configuration>
+              </execution>
+            </executions>
+          </plugin>
+        </plugins>
+      </build>
+    </profile>
+  </profiles>
+
   <dependencies>
     <dependency>
       <groupId>io.netty</groupId>
@@ -43,6 +113,22 @@
       <artifactId>netty-buffer</artifactId>
       <version>${project.version}</version>
     </dependency>
+    <dependency>
+      <groupId>io.netty</groupId>
+      <artifactId>netty-transport-native-unix-common</artifactId>
+      <version>${project.version}</version>
+      <classifier>${jni.classifier}</classifier>
+      <!--
+      The unix-common with classifier dependency is optional because it is not a runtime dependency, but a build time
+      dependency to get the static library which is built directly into the shared library generated by this project.
+      -->
+      <optional>true</optional>
+    </dependency>
+    <dependency>
+      <groupId>io.netty</groupId>
+      <artifactId>netty-transport-native-unix-common</artifactId>
+      <version>${project.version}</version>
+    </dependency>
     <dependency>
       <groupId>io.netty</groupId>
       <artifactId>netty-transport</artifactId>
@@ -54,6 +140,12 @@
       <version>${project.version}</version>
       <scope>test</scope>
     </dependency>
+    <dependency>
+      <groupId>io.netty</groupId>
+      <artifactId>netty-transport-native-unix-common-tests</artifactId>
+      <version>${project.version}</version>
+      <scope>test</scope>
+    </dependency>
     <dependency>
       <groupId>${project.groupId}</groupId>
       <artifactId>${tcnative.artifactId}</artifactId>
@@ -64,6 +156,29 @@
 
   <build>
     <plugins>
+      <plugin>
+        <artifactId>maven-dependency-plugin</artifactId>
+        <executions>
+          <!-- unpack the unix-common static library and include files -->
+          <execution>
+            <id>unpack</id>
+            <phase>generate-sources</phase>
+            <goals>
+              <goal>unpack-dependencies</goal>
+            </goals>
+            <configuration>
+              <includeGroupIds>${project.groupId}</includeGroupIds>
+              <includeArtifactIds>netty-transport-native-unix-common</includeArtifactIds>
+              <classifier>${jni.classifier}</classifier>
+              <outputDirectory>${unix.common.lib.dir}</outputDirectory>
+              <includes>META-INF/native/**</includes>
+              <overWriteReleases>false</overWriteReleases>
+              <overWriteSnapshots>true</overWriteSnapshots>
+            </configuration>
+          </execution>
+        </executions>
+      </plugin>
+
       <plugin>
         <groupId>org.fusesource.hawtjni</groupId>
         <artifactId>maven-hawtjni-plugin</artifactId>
@@ -122,7 +237,7 @@
                 <index>true</index>
                 <manifestFile>${project.build.outputDirectory}/META-INF/MANIFEST.MF</manifestFile>
               </archive>
-              <classifier>${epoll.classifier}</classifier>
+              <classifier>${jni.classifier}</classifier>
             </configuration>
           </execution>
         </executions>
@@ -201,7 +316,7 @@
               <value>${linux.sendmmsg.support}${glibc.sendmmsg.support}</value>
               <!-- If glibc and linux kernel are both not sufficient...then define the CFLAGS -->
               <regex>.*IO_NETTY_SENDMSSG_NOT_FOUND.*</regex>
-              <replacement>CFLAGS=-O3 -DIO_NETTY_SENDMMSG_NOT_FOUND -Werror -fno-omit-frame-pointer -Wunused-variable</replacement>
+              <replacement>CFLAGS=-O3 -DIO_NETTY_SENDMMSG_NOT_FOUND -Werror -fno-omit-frame-pointer -Wunused-variable -I${unix.common.include.unpacked.dir}</replacement>
               <failIfNoMatch>false</failIfNoMatch>
             </configuration>
           </execution>
@@ -217,7 +332,7 @@
               <value>${jni.compiler.args.cflags}</value>
               <!-- If glibc and linux kernel are both not sufficient...then define the CFLAGS -->
               <regex>^((?!CFLAGS=).)*$</regex>
-              <replacement>CFLAGS=-O3 -Werror -fno-omit-frame-pointer -Wunused-variable</replacement>
+              <replacement>CFLAGS=-O3 -Werror -fno-omit-frame-pointer -Wunused-variable -I${unix.common.include.unpacked.dir}</replacement>
               <failIfNoMatch>false</failIfNoMatch>
             </configuration>
           </execution>

transport-native-epoll/src/main/c/netty_epoll_linuxsocket.c

@@ -0,0 +1,346 @@
+/*
+ * Copyright 2016 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache License,
+ * version 2.0 (the "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at:
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+
+/*
+ * Since glibc 2.8, the _GNU_SOURCE feature test macro must be defined
+ * (before including any header files) in order to obtain the
+ * definition of the ucred structure. See <a href=https://linux.die.net/man/7/unix>
+ */
+#define _GNU_SOURCE
+
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+#include <netinet/in.h>
+#include <linux/tcp.h> // TCP_NOTSENT_LOWAT is a linux specific define
+#include "netty_unix_filedescriptor.h"
+#include "netty_unix_socket.h"
+#include "netty_unix_errors.h"
+#include "netty_unix_util.h"
+#include "netty_epoll_linuxsocket.h"
+
+// TCP_FASTOPEN is defined in linux 3.7. We define this here so older kernels can compile.
+#ifndef TCP_FASTOPEN
+#define TCP_FASTOPEN 23
+#endif
+
+// TCP_NOTSENT_LOWAT is defined in linux 3.12. We define this here so older kernels can compile.
+#ifndef TCP_NOTSENT_LOWAT
+#define TCP_NOTSENT_LOWAT 25
+#endif
+
+static jclass peerCredentialsClass = NULL;
+static jmethodID peerCredentialsMethodId = NULL;
+
+// JNI Registered Methods Begin
+static void netty_epoll_linuxsocket_setTcpCork(JNIEnv* env, jclass clazz, jint fd, jint optval) {
+    netty_unix_socket_setOption(env, fd, IPPROTO_TCP, TCP_CORK, &optval, sizeof(optval));
+}
+
+static void netty_epoll_linuxsocket_setTcpQuickAck(JNIEnv* env, jclass clazz, jint fd, jint optval) {
+    netty_unix_socket_setOption(env, fd, IPPROTO_TCP, TCP_QUICKACK, &optval, sizeof(optval));
+}
+
+static void netty_epoll_linuxsocket_setTcpDeferAccept(JNIEnv* env, jclass clazz, jint fd, jint optval) {
+    netty_unix_socket_setOption(env, fd, IPPROTO_TCP, TCP_DEFER_ACCEPT, &optval, sizeof(optval));
+}
+
+static void netty_epoll_linuxsocket_setTcpNotSentLowAt(JNIEnv* env, jclass clazz, jint fd, jint optval) {
+    netty_unix_socket_setOption(env, fd, IPPROTO_TCP, TCP_NOTSENT_LOWAT, &optval, sizeof(optval));
+}
+
+static void netty_epoll_linuxsocket_setTcpFastOpen(JNIEnv* env, jclass clazz, jint fd, jint optval) {
+    netty_unix_socket_setOption(env, fd, IPPROTO_TCP, TCP_FASTOPEN, &optval, sizeof(optval));
+}
+
+static void netty_epoll_linuxsocket_setTcpKeepIdle(JNIEnv* env, jclass clazz, jint fd, jint optval) {
+    netty_unix_socket_setOption(env, fd, IPPROTO_TCP, TCP_KEEPIDLE, &optval, sizeof(optval));
+}
+
+static void netty_epoll_linuxsocket_setTcpKeepIntvl(JNIEnv* env, jclass clazz, jint fd, jint optval) {
+    netty_unix_socket_setOption(env, fd, IPPROTO_TCP, TCP_KEEPINTVL, &optval, sizeof(optval));
+}
+
+static void netty_epoll_linuxsocket_setTcpKeepCnt(JNIEnv* env, jclass clazz, jint fd, jint optval) {
+    netty_unix_socket_setOption(env, fd, IPPROTO_TCP, TCP_KEEPCNT, &optval, sizeof(optval));
+}
+
+static void netty_epoll_linuxsocket_setTcpUserTimeout(JNIEnv* env, jclass clazz, jint fd, jint optval) {
+    netty_unix_socket_setOption(env, fd, IPPROTO_TCP, TCP_USER_TIMEOUT, &optval, sizeof(optval));
+}
+
+static void netty_epoll_linuxsocket_setIpFreeBind(JNIEnv* env, jclass clazz, jint fd, jint optval) {
+    netty_unix_socket_setOption(env, fd, IPPROTO_IP, IP_FREEBIND, &optval, sizeof(optval));
+}
+
+static void netty_epoll_linuxsocket_setTcpMd5Sig(JNIEnv* env, jclass clazz, jint fd, jbyteArray address, jint scopeId, jbyteArray key) {
+    struct sockaddr_storage addr;
+    socklen_t addrSize;
+    if (netty_unix_socket_initSockaddr(env, address, scopeId, 0, &addr, &addrSize) == -1) {
+        return;
+    }
+
+    struct tcp_md5sig md5sig;
+    memset(&md5sig, 0, sizeof(md5sig));
+    md5sig.tcpm_addr.ss_family = addr.ss_family;
+
+    struct sockaddr_in* ipaddr;
+    struct sockaddr_in6* ip6addr;
+
+    switch (addr.ss_family) {
+    case AF_INET:
+        ipaddr = (struct sockaddr_in*) &addr;
+        memcpy(&((struct sockaddr_in *) &md5sig.tcpm_addr)->sin_addr, &ipaddr->sin_addr, sizeof(ipaddr->sin_addr));
+        break;
+    case AF_INET6:
+        ip6addr = (struct sockaddr_in6*) &addr;
+        memcpy(&((struct sockaddr_in6 *) &md5sig.tcpm_addr)->sin6_addr, &ip6addr->sin6_addr, sizeof(ip6addr->sin6_addr));
+        break;
+    }
+
+    if (key != NULL) {
+        md5sig.tcpm_keylen = (*env)->GetArrayLength(env, key);
+        (*env)->GetByteArrayRegion(env, key, 0, md5sig.tcpm_keylen, (void *) &md5sig.tcpm_key);
+        if ((*env)->ExceptionCheck(env) == JNI_TRUE) {
+            return;
+        }
+    }
+
+    if (setsockopt(fd, IPPROTO_TCP, TCP_MD5SIG, &md5sig, sizeof(md5sig)) < 0) {
+        netty_unix_errors_throwChannelExceptionErrorNo(env, "setsockopt() failed: ", errno);
+    }
+}
+
+static jint netty_epoll_linuxsocket_getTcpKeepIdle(JNIEnv* env, jclass clazz, jint fd) {
+    int optval;
+    if (netty_unix_socket_getOption(env, fd, IPPROTO_TCP, TCP_KEEPIDLE, &optval, sizeof(optval)) == -1) {
+        return -1;
+    }
+    return optval;
+}
+
+static jint netty_epoll_linuxsocket_getTcpKeepIntvl(JNIEnv* env, jclass clazz, jint fd) {
+    int optval;
+    if (netty_unix_socket_getOption(env, fd, IPPROTO_TCP, TCP_KEEPINTVL, &optval, sizeof(optval)) == -1) {
+        return -1;
+    }
+    return optval;
+}
+
+static jint netty_epoll_linuxsocket_getTcpKeepCnt(JNIEnv* env, jclass clazz, jint fd) {
+     int optval;
+     if (netty_unix_socket_getOption(env, fd, IPPROTO_TCP, TCP_KEEPCNT, &optval, sizeof(optval)) == -1) {
+         return -1;
+     }
+     return optval;
+}
+
+static jint netty_epoll_linuxsocket_getTcpUserTimeout(JNIEnv* env, jclass clazz, jint fd) {
+     int optval;
+     if (netty_unix_socket_getOption(env, fd, IPPROTO_TCP, TCP_USER_TIMEOUT, &optval, sizeof(optval)) == -1) {
+         return -1;
+     }
+     return optval;
+}
+
+static jint netty_epoll_linuxsocket_isIpFreeBind(JNIEnv* env, jclass clazz, jint fd) {
+     int optval;
+     if (netty_unix_socket_getOption(env, fd, IPPROTO_IP, IP_FREEBIND, &optval, sizeof(optval)) == -1) {
+         return -1;
+     }
+     return optval;
+}
+
+static void netty_epoll_linuxsocket_getTcpInfo(JNIEnv* env, jclass clazz, jint fd, jintArray array) {
+     struct tcp_info tcp_info;
+     if (netty_unix_socket_getOption(env, fd, IPPROTO_TCP, TCP_INFO, &tcp_info, sizeof(tcp_info)) == -1) {
+         return;
+     }
+     unsigned int cArray[32];
+     cArray[0] = tcp_info.tcpi_state;
+     cArray[1] = tcp_info.tcpi_ca_state;
+     cArray[2] = tcp_info.tcpi_retransmits;
+     cArray[3] = tcp_info.tcpi_probes;
+     cArray[4] = tcp_info.tcpi_backoff;
+     cArray[5] = tcp_info.tcpi_options;
+     cArray[6] = tcp_info.tcpi_snd_wscale;
+     cArray[7] = tcp_info.tcpi_rcv_wscale;
+     cArray[8] = tcp_info.tcpi_rto;
+     cArray[9] = tcp_info.tcpi_ato;
+     cArray[10] = tcp_info.tcpi_snd_mss;
+     cArray[11] = tcp_info.tcpi_rcv_mss;
+     cArray[12] = tcp_info.tcpi_unacked;
+     cArray[13] = tcp_info.tcpi_sacked;
+     cArray[14] = tcp_info.tcpi_lost;
+     cArray[15] = tcp_info.tcpi_retrans;
+     cArray[16] = tcp_info.tcpi_fackets;
+     cArray[17] = tcp_info.tcpi_last_data_sent;
+     cArray[18] = tcp_info.tcpi_last_ack_sent;
+     cArray[19] = tcp_info.tcpi_last_data_recv;
+     cArray[20] = tcp_info.tcpi_last_ack_recv;
+     cArray[21] = tcp_info.tcpi_pmtu;
+     cArray[22] = tcp_info.tcpi_rcv_ssthresh;
+     cArray[23] = tcp_info.tcpi_rtt;
+     cArray[24] = tcp_info.tcpi_rttvar;
+     cArray[25] = tcp_info.tcpi_snd_ssthresh;
+     cArray[26] = tcp_info.tcpi_snd_cwnd;
+     cArray[27] = tcp_info.tcpi_advmss;
+     cArray[28] = tcp_info.tcpi_reordering;
+     cArray[29] = tcp_info.tcpi_rcv_rtt;
+     cArray[30] = tcp_info.tcpi_rcv_space;
+     cArray[31] = tcp_info.tcpi_total_retrans;
+
+     (*env)->SetIntArrayRegion(env, array, 0, 32, cArray);
+}
+
+static jint netty_epoll_linuxsocket_isTcpCork(JNIEnv* env, jclass clazz, jint fd) {
+    int optval;
+    if (netty_unix_socket_getOption(env, fd, IPPROTO_TCP, TCP_CORK, &optval, sizeof(optval)) == -1) {
+        return -1;
+    }
+    return optval;
+}
+
+static jint netty_epoll_linuxsocket_getTcpDeferAccept(JNIEnv* env, jclass clazz, jint fd) {
+    int optval;
+    if (netty_unix_socket_getOption(env, fd, IPPROTO_TCP, TCP_DEFER_ACCEPT, &optval, sizeof(optval)) == -1) {
+        return -1;
+    }
+    return optval;
+}
+
+static jint netty_epoll_linuxsocket_isTcpQuickAck(JNIEnv* env, jclass clazz, jint fd) {
+    int optval;
+    if (netty_unix_socket_getOption(env, fd, IPPROTO_TCP, TCP_QUICKACK, &optval, sizeof(optval)) == -1) {
+        return -1;
+    }
+    return optval;
+}
+
+static jint netty_epoll_linuxsocket_getTcpNotSentLowAt(JNIEnv* env, jclass clazz, jint fd) {
+    int optval;
+    if (netty_unix_socket_getOption(env, fd, IPPROTO_TCP, TCP_NOTSENT_LOWAT, &optval, sizeof(optval)) == -1) {
+        return -1;
+    }
+    return optval;
+}
+
+static jobject netty_epoll_linuxsocket_getPeerCredentials(JNIEnv *env, jclass clazz, jint fd) {
+     struct ucred credentials;
+     if(netty_unix_socket_getOption(env,fd, SOL_SOCKET, SO_PEERCRED, &credentials, sizeof (credentials)) == -1) {
+         return NULL;
+     }
+     jintArray gids = (*env)->NewIntArray(env, 1);
+     (*env)->SetIntArrayRegion(env, gids, 0, 1, (jint*) &credentials.gid);
+     return (*env)->NewObject(env, peerCredentialsClass, peerCredentialsMethodId, credentials.pid, credentials.uid, gids);
+}
+// JNI Registered Methods End
+
+// JNI Method Registration Table Begin
+static const JNINativeMethod fixed_method_table[] = {
+  { "setTcpCork", "(II)V", (void *) netty_epoll_linuxsocket_setTcpCork },
+  { "setTcpQuickAck", "(II)V", (void *) netty_epoll_linuxsocket_setTcpQuickAck },
+  { "setTcpDeferAccept", "(II)V", (void *) netty_epoll_linuxsocket_setTcpDeferAccept },
+  { "setTcpNotSentLowAt", "(II)V", (void *) netty_epoll_linuxsocket_setTcpNotSentLowAt },
+  { "isTcpCork", "(I)I", (void *) netty_epoll_linuxsocket_isTcpCork },
+  { "getTcpDeferAccept", "(I)I", (void *) netty_epoll_linuxsocket_getTcpDeferAccept },
+  { "getTcpNotSentLowAt", "(I)I", (void *) netty_epoll_linuxsocket_getTcpNotSentLowAt },
+  { "isTcpQuickAck", "(I)I", (void *) netty_epoll_linuxsocket_isTcpQuickAck },
+  { "setTcpFastOpen", "(II)V", (void *) netty_epoll_linuxsocket_setTcpFastOpen },
+  { "setTcpKeepIdle", "(II)V", (void *) netty_epoll_linuxsocket_setTcpKeepIdle },
+  { "setTcpKeepIntvl", "(II)V", (void *) netty_epoll_linuxsocket_setTcpKeepIntvl },
+  { "setTcpKeepCnt", "(II)V", (void *) netty_epoll_linuxsocket_setTcpKeepCnt },
+  { "setTcpUserTimeout", "(II)V", (void *) netty_epoll_linuxsocket_setTcpUserTimeout },
+  { "setIpFreeBind", "(II)V", (void *) netty_epoll_linuxsocket_setIpFreeBind },
+  { "getTcpKeepIdle", "(I)I", (void *) netty_epoll_linuxsocket_getTcpKeepIdle },
+  { "getTcpKeepIntvl", "(I)I", (void *) netty_epoll_linuxsocket_getTcpKeepIntvl },
+  { "getTcpKeepCnt", "(I)I", (void *) netty_epoll_linuxsocket_getTcpKeepCnt },
+  { "getTcpUserTimeout", "(I)I", (void *) netty_epoll_linuxsocket_getTcpUserTimeout },
+  { "isIpFreeBind", "(I)I", (void *) netty_epoll_linuxsocket_isIpFreeBind },
+  { "getTcpInfo", "(I[I)V", (void *) netty_epoll_linuxsocket_getTcpInfo },
+  { "setTcpMd5Sig", "(I[BI[B)V", (void *) netty_epoll_linuxsocket_setTcpMd5Sig }
+};
+
+static const jint fixed_method_table_size = sizeof(fixed_method_table) / sizeof(fixed_method_table[0]);
+
+static jint dynamicMethodsTableSize() {
+    return fixed_method_table_size + 1;
+}
+
+static JNINativeMethod* createDynamicMethodsTable(const char* packagePrefix) {
+    JNINativeMethod* dynamicMethods = malloc(sizeof(JNINativeMethod) * dynamicMethodsTableSize());
+    memcpy(dynamicMethods, fixed_method_table, sizeof(fixed_method_table));
+    JNINativeMethod* dynamicMethod = &dynamicMethods[fixed_method_table_size];
+    char* dynamicTypeName = netty_unix_util_prepend(packagePrefix, "io/netty/channel/unix/PeerCredentials;");
+    dynamicMethod->name = "getPeerCredentials";
+    dynamicMethod->signature = netty_unix_util_prepend("(I)L", dynamicTypeName);
+    dynamicMethod->fnPtr = (void *) netty_epoll_linuxsocket_getPeerCredentials;
+    free(dynamicTypeName);
+    return dynamicMethods;
+}
+
+static void freeDynamicMethodsTable(JNINativeMethod* dynamicMethods) {
+    jint fullMethodTableSize = dynamicMethodsTableSize();
+    jint i = fixed_method_table_size;
+    for (; i < fullMethodTableSize; ++i) {
+        free(dynamicMethods[i].signature);
+    }
+    free(dynamicMethods);
+}
+// JNI Method Registration Table End
+
+jint netty_epoll_linuxsocket_JNI_OnLoad(JNIEnv* env, const char* packagePrefix) {
+    JNINativeMethod* dynamicMethods = createDynamicMethodsTable(packagePrefix);
+    if (netty_unix_util_register_natives(env,
+            packagePrefix,
+            "io/netty/channel/epoll/LinuxSocket",
+            dynamicMethods,
+            dynamicMethodsTableSize()) != 0) {
+        freeDynamicMethodsTable(dynamicMethods);
+        return JNI_ERR;
+    }
+    freeDynamicMethodsTable(dynamicMethods);
+    dynamicMethods = NULL;
+
+    char* nettyClassName = netty_unix_util_prepend(packagePrefix, "io/netty/channel/unix/PeerCredentials");
+    jclass localPeerCredsClass = (*env)->FindClass(env, nettyClassName);
+    free(nettyClassName);
+    nettyClassName = NULL;
+    if (localPeerCredsClass == NULL) {
+        // pending exception...
+        return JNI_ERR;
+    }
+    peerCredentialsClass = (jclass) (*env)->NewGlobalRef(env, localPeerCredsClass);
+    if (peerCredentialsClass == NULL) {
+        // out-of-memory!
+        netty_unix_errors_throwOutOfMemoryError(env);
+        return JNI_ERR;
+    }
+    peerCredentialsMethodId = (*env)->GetMethodID(env, peerCredentialsClass, "<init>", "(II[I)V");
+    if (peerCredentialsMethodId == NULL) {
+        netty_unix_errors_throwRuntimeException(env, "failed to get method ID: PeerCredentials.<init>(int, int, int[])");
+        return JNI_ERR;
+    }
+
+    return JNI_VERSION_1_6;
+}
+
+void netty_epoll_linuxsocket_JNI_OnUnLoad(JNIEnv* env) {
+    if (peerCredentialsClass != NULL) {
+        (*env)->DeleteGlobalRef(env, peerCredentialsClass);
+        peerCredentialsClass = NULL;
+    }
+}

transport-native-epoll/src/main/c/netty_epoll_linuxsocket.h

@@ -0,0 +1,26 @@
+/*
+ * Copyright 2016 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache License,
+ * version 2.0 (the "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at:
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+
+#ifndef NETTY_EPOLL_LINUXSOCKET_H_
+#define NETTY_EPOLL_LINUXSOCKET_H_
+
+#include <jni.h>
+
+// JNI initialization hooks. Users of this file are responsible for calling these in the JNI_OnLoad and JNI_OnUnload methods.
+jint netty_epoll_linuxsocket_JNI_OnLoad(JNIEnv* env, const char* packagePrefix);
+void netty_epoll_linuxsocket_JNI_OnUnLoad(JNIEnv* env);
+
+#endif

transport-native-epoll/src/main/c/netty_epoll_native.c

@@ -23,8 +23,8 @@
 #include <sys/eventfd.h>
 #include <sys/sendfile.h>
 #include <sys/un.h>
-#include <linux/tcp.h> // TCP_NOTSENT_LOWAT is a linux specific define
 #include <netinet/in.h>
+#include <netinet/tcp.h>
 #include <sys/types.h>
 #include <sys/socket.h>
 #include <unistd.h>
@@ -40,28 +40,8 @@
 #include "netty_unix_socket.h"
 #include "netty_unix_errors.h"
 #include "netty_unix_util.h"
-
+#include "netty_unix_limits.h"
-// Define SO_REUSEPORT if not found to fix build issues.
+#include "netty_epoll_linuxsocket.h"
-// See https://github.com/netty/netty/issues/2558
-#ifndef SO_REUSEPORT
-#define SO_REUSEPORT 15
-#endif /* SO_REUSEPORT */
-
-// Define IOV_MAX if not found to limit the iov size on writev calls
-// See https://github.com/netty/netty/issues/2647
-#ifndef IOV_MAX
-#define IOV_MAX 1024
-#endif /* IOV_MAX */
-
-// Define UIO_MAXIOV if not found
-#ifndef UIO_MAXIOV
-#define UIO_MAXIOV 1024
-#endif /* UIO_MAXIOV */
-
-// TCP_NOTSENT_LOWAT is defined in linux 3.12. We define this here so older kernels can compile.
-#ifndef TCP_NOTSENT_LOWAT
-#define TCP_NOTSENT_LOWAT 25
-#endif
 
 // TCP_FASTOPEN is defined in linux 3.7. We define this here so older kernels can compile.
 #ifndef TCP_FASTOPEN
@@ -104,49 +84,9 @@ jfieldID packetPortFieldId = NULL;
 jfieldID packetMemoryAddressFieldId = NULL;
 jfieldID packetCountFieldId = NULL;
 
-clockid_t epollWaitClock = 0; // initialized in initializeEpollWaitClock
+clockid_t waitClockId = 0; // initialized by netty_unix_util_initialize_wait_clock
 
 // util methods
-static jboolean initializeEpollWaitClock() {
-  struct timespec ts;
-  // First try to get a monotonic clock, as we effectively measure execution time and don't want the underlying clock
-  // moving unexpectedly/abruptly.
-  #ifdef CLOCK_MONOTONIC_COARSE
-  epollWaitClock = CLOCK_MONOTONIC_COARSE;
-  if (clock_gettime(epollWaitClock, &ts) != EINVAL) {
-    return JNI_TRUE;
-  }
-  #endif
-  #ifdef CLOCK_MONOTONIC_RAW
-  epollWaitClock = CLOCK_MONOTONIC_RAW;
-  if (clock_gettime(epollWaitClock, &ts) != EINVAL) {
-    return JNI_TRUE;
-  }
-  #endif
-  #ifdef CLOCK_MONOTONIC
-  epollWaitClock = CLOCK_MONOTONIC;
-  if (clock_gettime(epollWaitClock, &ts) != EINVAL) {
-    return JNI_TRUE;
-  }
-  #endif
-
-  // Fallback to realtime ... in this case we are subject to clock movements on the system.
-  #ifdef CLOCK_REALTIME_COARSE
-  epollWaitClock = CLOCK_REALTIME_COARSE;
-  if (clock_gettime(epollWaitClock, &ts) != EINVAL) {
-    return JNI_TRUE;
-  }
-  #endif
-  #ifdef CLOCK_REALTIME
-  epollWaitClock = CLOCK_REALTIME;
-  if (clock_gettime(epollWaitClock, &ts) != EINVAL) {
-    return JNI_TRUE;
-  }
-  #endif
-  fprintf(stderr, "FATAL: could not find a clock for clock_gettime!\n");
-  return JNI_FALSE;
-}
-
 static int getSysctlValue(const char * property, int* returnValue) {
     int rc = -1;
     FILE *fd=fopen(property, "r");
@@ -238,7 +178,7 @@ static jint netty_epoll_native_epollWait0(JNIEnv* env, jclass clazz, jint efd, j
         timeout = MAX_EPOLL_TIMEOUT_MSEC;
     }
 
-    clock_gettime(epollWaitClock, &ts);
+    clock_gettime(waitClockId, &ts);
     timeBeforeWait = ts.tv_sec * 1000 + ts.tv_nsec / 1000000;
 
     for (;;) {
@@ -248,7 +188,7 @@ static jint netty_epoll_native_epollWait0(JNIEnv* env, jclass clazz, jint efd, j
       }
       if ((err = errno) == EINTR) {
         if (timeout > 0) {
-          clock_gettime(epollWaitClock, &ts);
+          clock_gettime(waitClockId, &ts);
           timeNow = ts.tv_sec * 1000 + ts.tv_nsec / 1000000;
           timeDiff = timeNow - timeBeforeWait;
           timeout -= timeDiff;
@@ -293,6 +233,7 @@ static jint netty_epoll_native_epollCtlDel0(JNIEnv* env, jclass clazz, jint efd,
 static jint netty_epoll_native_sendmmsg0(JNIEnv* env, jclass clazz, jint fd, jobjectArray packets, jint offset, jint len) {
     struct mmsghdr msg[len];
     struct sockaddr_storage addr[len];
+    socklen_t addrSize;
     int i;
 
     memset(msg, 0, sizeof(msg));
@@ -304,12 +245,12 @@ static jint netty_epoll_native_sendmmsg0(JNIEnv* env, jclass clazz, jint fd, job
         jint scopeId = (*env)->GetIntField(env, packet, packetScopeIdFieldId);
         jint port = (*env)->GetIntField(env, packet, packetPortFieldId);
 
-        if (netty_unix_socket_initSockaddr(env, address, scopeId, port, &addr[i]) == -1) {
+        if (netty_unix_socket_initSockaddr(env, address, scopeId, port, &addr[i], &addrSize) == -1) {
             return -1;
         }
 
         msg[i].msg_hdr.msg_name = &addr[i];
-        msg[i].msg_hdr.msg_namelen = sizeof(addr[i]);
+        msg[i].msg_hdr.msg_namelen = addrSize;
 
         msg[i].msg_hdr.msg_iov = (struct iovec*) (intptr_t) (*env)->GetLongField(env, packet, packetMemoryAddressFieldId);
         msg[i].msg_hdr.msg_iovlen = (*env)->GetIntField(env, packet, packetCountFieldId);;
@@ -327,89 +268,6 @@ static jint netty_epoll_native_sendmmsg0(JNIEnv* env, jclass clazz, jint fd, job
     }
     return (jint) res;
 }
-static jint netty_epoll_native_recvFd0(JNIEnv* env, jclass clazz, jint fd) {
-    int socketFd;
-    struct msghdr descriptorMessage = { 0 };
-    struct iovec iov[1] = { 0 };
-    char control[CMSG_SPACE(sizeof(int))] = { 0 };
-    char iovecData[1];
-
-    descriptorMessage.msg_control = control;
-    descriptorMessage.msg_controllen = sizeof(control);
-    descriptorMessage.msg_iov = iov;
-    descriptorMessage.msg_iovlen = 1;
-    iov[0].iov_base = iovecData;
-    iov[0].iov_len = sizeof(iovecData);
-
-    ssize_t res;
-    int err;
-
-    for (;;) {
-        do {
-            res = recvmsg(fd, &descriptorMessage, 0);
-            // Keep on reading if we was interrupted
-        } while (res == -1 && ((err = errno) == EINTR));
-
-        if (res == 0) {
-            return 0;
-        }
-
-        if (res < 0) {
-            return -err;
-        }
-
-        struct cmsghdr* cmsg = CMSG_FIRSTHDR(&descriptorMessage);
-        if (!cmsg) {
-            return -errno;
-        }
-
-        if ((cmsg->cmsg_len == CMSG_LEN(sizeof(int))) && (cmsg->cmsg_level == SOL_SOCKET) && (cmsg->cmsg_type == SCM_RIGHTS)) {
-            socketFd = *((int *) CMSG_DATA(cmsg));
-            // set as non blocking as we want to use it with epoll
-            if (fcntl(socketFd, F_SETFL, O_NONBLOCK) == -1) {
-                err = errno;
-                close(socketFd);
-                return -err;
-            }
-            return socketFd;
-        }
-    }
-}
-
-static jint netty_epoll_native_sendFd0(JNIEnv* env, jclass clazz, jint socketFd, jint fd) {
-    struct msghdr descriptorMessage = { 0 };
-    struct iovec iov[1] = { 0 };
-    char control[CMSG_SPACE(sizeof(int))] = { 0 };
-    char iovecData[1];
-
-    descriptorMessage.msg_control = control;
-    descriptorMessage.msg_controllen = sizeof(control);
-    struct cmsghdr* cmsg = CMSG_FIRSTHDR(&descriptorMessage);
-
-    if (cmsg) {
-        cmsg->cmsg_len = CMSG_LEN(sizeof(int));
-        cmsg->cmsg_level = SOL_SOCKET;
-        cmsg->cmsg_type = SCM_RIGHTS;
-        *((int *)CMSG_DATA(cmsg)) = fd;
-        descriptorMessage.msg_iov = iov;
-        descriptorMessage.msg_iovlen = 1;
-        iov[0].iov_base = iovecData;
-        iov[0].iov_len = sizeof(iovecData);
-
-        ssize_t res;
-        int err;
-        do {
-            res = sendmsg(socketFd, &descriptorMessage, 0);
-        // keep on writing if it was interrupted
-        } while (res == -1 && ((err = errno) == EINTR));
-
-        if (res < 0) {
-            return -err;
-        }
-        return (jint) res;
-    }
-    return -1;
-}
 
 static jlong netty_epoll_native_sendfile0(JNIEnv* env, jclass clazz, jint fd, jobject fileRegion, jlong base_off, jlong off, jlong len) {
     jobject fileChannel = (*env)->GetObjectField(env, fileRegion, fileChannelFieldId);
@@ -443,177 +301,6 @@ static jlong netty_epoll_native_sendfile0(JNIEnv* env, jclass clazz, jint fd, jo
 
     return res;
 }
-static void netty_epoll_native_setReuseAddress(JNIEnv* env, jclass clazz, jint fd, jint optval) {
-    netty_unix_socket_setOption(env, fd, SOL_SOCKET, SO_REUSEADDR, &optval, sizeof(optval));
-}
-
-static void netty_epoll_native_setReusePort(JNIEnv* env, jclass clazz, jint fd, jint optval) {
-    netty_unix_socket_setOption(env, fd, SOL_SOCKET, SO_REUSEPORT, &optval, sizeof(optval));
-}
-
-static void netty_epoll_native_setTcpFastopen(JNIEnv* env, jclass clazz, jint fd, jint optval) {
-    netty_unix_socket_setOption(env, fd, IPPROTO_TCP, TCP_FASTOPEN, &optval, sizeof(optval));
-}
-
-static void netty_epoll_native_setTcpNotSentLowAt(JNIEnv* env, jclass clazz, jint fd, jint optval) {
-    netty_unix_socket_setOption(env, fd, IPPROTO_TCP, TCP_NOTSENT_LOWAT, &optval, sizeof(optval));
-}
-
-static void netty_epoll_native_setTrafficClass(JNIEnv* env, jclass clazz, jint fd, jint optval) {
-    netty_unix_socket_setOption(env, fd, IPPROTO_IP, IP_TOS, &optval, sizeof(optval));
-
-    /* Try to set the ipv6 equivalent, but don't throw if this is an ipv4 only socket. */
-    int rc = setsockopt(fd, IPPROTO_IPV6, IPV6_TCLASS, &optval, sizeof(optval));
-    if (rc < 0 && errno != ENOPROTOOPT) {
-        netty_unix_errors_throwChannelExceptionErrorNo(env, "setting ipv6 dscp failed: ", errno);
-    }
-}
-
-static void netty_epoll_native_setBroadcast(JNIEnv* env, jclass clazz, jint fd, jint optval) {
-    netty_unix_socket_setOption(env, fd, SOL_SOCKET, SO_BROADCAST, &optval, sizeof(optval));
-}
-
-static void netty_epoll_native_setTcpKeepIdle(JNIEnv* env, jclass clazz, jint fd, jint optval) {
-    netty_unix_socket_setOption(env, fd, IPPROTO_TCP, TCP_KEEPIDLE, &optval, sizeof(optval));
-}
-
-static void netty_epoll_native_setTcpKeepIntvl(JNIEnv* env, jclass clazz, jint fd, jint optval) {
-    netty_unix_socket_setOption(env, fd, IPPROTO_TCP, TCP_KEEPINTVL, &optval, sizeof(optval));
-}
-
-static void netty_epoll_native_setTcpKeepCnt(JNIEnv* env, jclass clazz, jint fd, jint optval) {
-    netty_unix_socket_setOption(env, fd, IPPROTO_TCP, TCP_KEEPCNT, &optval, sizeof(optval));
-}
-
-static void netty_epoll_native_setTcpUserTimeout(JNIEnv* env, jclass clazz, jint fd, jint optval) {
-    netty_unix_socket_setOption(env, fd, IPPROTO_TCP, TCP_USER_TIMEOUT, &optval, sizeof(optval));
-}
-
-static void netty_epoll_native_setIpFreeBind(JNIEnv* env, jclass clazz, jint fd, jint optval) {
-    netty_unix_socket_setOption(env, fd, IPPROTO_IP, IP_FREEBIND, &optval, sizeof(optval));
-}
-
-static jint netty_epoll_native_isReuseAddress(JNIEnv* env, jclass clazz, jint fd) {
-    int optval;
-    if (netty_unix_socket_getOption(env, fd, SOL_SOCKET, SO_REUSEADDR, &optval, sizeof(optval)) == -1) {
-        return -1;
-    }
-    return optval;
-}
-
-static jint netty_epoll_native_isReusePort(JNIEnv* env, jclass clazz, jint fd) {
-    int optval;
-    if (netty_unix_socket_getOption(env, fd, SOL_SOCKET, SO_REUSEPORT, &optval, sizeof(optval)) == -1) {
-        return -1;
-    }
-    return optval;
-}
-
-static jint netty_epoll_native_getTcpNotSentLowAt(JNIEnv* env, jclass clazz, jint fd) {
-    int optval;
-    if (netty_unix_socket_getOption(env, fd, IPPROTO_TCP, TCP_NOTSENT_LOWAT, &optval, sizeof(optval)) == -1) {
-        return -1;
-    }
-    return optval;
-}
-
-static jint netty_epoll_native_getTrafficClass(JNIEnv* env, jclass clazz, jint fd) {
-    int optval;
-    if (netty_unix_socket_getOption(env, fd, IPPROTO_IP, IP_TOS, &optval, sizeof(optval)) == -1) {
-        return -1;
-    }
-    return optval;
-}
-
-static jint netty_epoll_native_isBroadcast(JNIEnv* env, jclass clazz, jint fd) {
-    int optval;
-    if (netty_unix_socket_getOption(env, fd, SOL_SOCKET, SO_BROADCAST, &optval, sizeof(optval)) == -1) {
-        return -1;
-    }
-    return optval;
-}
-
-static jint netty_epoll_native_getTcpKeepIdle(JNIEnv* env, jclass clazz, jint fd) {
-    int optval;
-    if (netty_unix_socket_getOption(env, fd, IPPROTO_TCP, TCP_KEEPIDLE, &optval, sizeof(optval)) == -1) {
-        return -1;
-    }
-    return optval;
-}
-
-static jint netty_epoll_native_getTcpKeepIntvl(JNIEnv* env, jclass clazz, jint fd) {
-    int optval;
-    if (netty_unix_socket_getOption(env, fd, IPPROTO_TCP, TCP_KEEPINTVL, &optval, sizeof(optval)) == -1) {
-        return -1;
-    }
-    return optval;
-}
-
-static jint netty_epoll_native_getTcpKeepCnt(JNIEnv* env, jclass clazz, jint fd) {
-     int optval;
-     if (netty_unix_socket_getOption(env, fd, IPPROTO_TCP, TCP_KEEPCNT, &optval, sizeof(optval)) == -1) {
-         return -1;
-     }
-     return optval;
-}
-
-static jint netty_epoll_native_getTcpUserTimeout(JNIEnv* env, jclass clazz, jint fd) {
-     int optval;
-     if (netty_unix_socket_getOption(env, fd, IPPROTO_TCP, TCP_USER_TIMEOUT, &optval, sizeof(optval)) == -1) {
-         return -1;
-     }
-     return optval;
-}
-
-static jint netty_epoll_Native_isIpFreeBind(JNIEnv* env, jclass clazz, jint fd) {
-     int optval;
-     if (netty_unix_socket_getOption(env, fd, IPPROTO_IP, IP_FREEBIND, &optval, sizeof(optval)) == -1) {
-         return -1;
-     }
-     return optval;
-}
-
-static void netty_epoll_native_tcpInfo0(JNIEnv* env, jclass clazz, jint fd, jintArray array) {
-     struct tcp_info tcp_info;
-     if (netty_unix_socket_getOption(env, fd, IPPROTO_TCP, TCP_INFO, &tcp_info, sizeof(tcp_info)) == -1) {
-         return;
-     }
-     unsigned int cArray[32];
-     cArray[0] = tcp_info.tcpi_state;
-     cArray[1] = tcp_info.tcpi_ca_state;
-     cArray[2] = tcp_info.tcpi_retransmits;
-     cArray[3] = tcp_info.tcpi_probes;
-     cArray[4] = tcp_info.tcpi_backoff;
-     cArray[5] = tcp_info.tcpi_options;
-     cArray[6] = tcp_info.tcpi_snd_wscale;
-     cArray[7] = tcp_info.tcpi_rcv_wscale;
-     cArray[8] = tcp_info.tcpi_rto;
-     cArray[9] = tcp_info.tcpi_ato;
-     cArray[10] = tcp_info.tcpi_snd_mss;
-     cArray[11] = tcp_info.tcpi_rcv_mss;
-     cArray[12] = tcp_info.tcpi_unacked;
-     cArray[13] = tcp_info.tcpi_sacked;
-     cArray[14] = tcp_info.tcpi_lost;
-     cArray[15] = tcp_info.tcpi_retrans;
-     cArray[16] = tcp_info.tcpi_fackets;
-     cArray[17] = tcp_info.tcpi_last_data_sent;
-     cArray[18] = tcp_info.tcpi_last_ack_sent;
-     cArray[19] = tcp_info.tcpi_last_data_recv;
-     cArray[20] = tcp_info.tcpi_last_ack_recv;
-     cArray[21] = tcp_info.tcpi_pmtu;
-     cArray[22] = tcp_info.tcpi_rcv_ssthresh;
-     cArray[23] = tcp_info.tcpi_rtt;
-     cArray[24] = tcp_info.tcpi_rttvar;
-     cArray[25] = tcp_info.tcpi_snd_ssthresh;
-     cArray[26] = tcp_info.tcpi_snd_cwnd;
-     cArray[27] = tcp_info.tcpi_advmss;
-     cArray[28] = tcp_info.tcpi_reordering;
-     cArray[29] = tcp_info.tcpi_rcv_rtt;
-     cArray[30] = tcp_info.tcpi_rcv_space;
-     cArray[31] = tcp_info.tcpi_total_retrans;
-
-     (*env)->SetIntArrayRegion(env, array, 0, 32, cArray);
-}
 
 static jstring netty_epoll_native_kernelVersion(JNIEnv* env, jclass clazz) {
     struct utsname name;
@@ -627,14 +314,6 @@ static jstring netty_epoll_native_kernelVersion(JNIEnv* env, jclass clazz) {
     return NULL;
 }
 
-static jint netty_epoll_native_iovMax(JNIEnv* env, jclass clazz) {
-    return IOV_MAX;
-}
-
-static jint netty_epoll_native_uioMaxIov(JNIEnv* env, jclass clazz) {
-    return UIO_MAXIOV;
-}
-
 static jboolean netty_epoll_native_isSupportingSendmmsg(JNIEnv* env, jclass clazz) {
     if (sendmmsg) {
         return JNI_TRUE;
@@ -699,10 +378,6 @@ static jint netty_epoll_native_splice0(JNIEnv* env, jclass clazz, jint fd, jlong
     return (jint) res;
 }
 
-static jlong netty_epoll_native_ssizeMax(JNIEnv* env, jclass clazz) {
-    return SSIZE_MAX;
-}
-
 static jint netty_epoll_native_tcpMd5SigMaxKeyLen(JNIEnv* env, jclass clazz) {
     struct tcp_md5sig md5sig;
 
@@ -713,43 +388,6 @@ static jint netty_epoll_native_tcpMd5SigMaxKeyLen(JNIEnv* env, jclass clazz) {
 
     return TCP_MD5SIG_MAXKEYLEN;
 }
-
-static void netty_epoll_native_setTcpMd5Sig0(JNIEnv* env, jclass clazz, jint fd, jbyteArray address, jint scopeId, jbyteArray key) {
-    struct sockaddr_storage addr;
-    if (netty_unix_socket_initSockaddr(env, address, scopeId, 0, &addr) == -1) {
-        return;
-    }
-
-    struct tcp_md5sig md5sig;
-    memset(&md5sig, 0, sizeof(md5sig));
-    md5sig.tcpm_addr.ss_family = addr.ss_family;
-
-    struct sockaddr_in* ipaddr;
-    struct sockaddr_in6* ip6addr;
-
-    switch (addr.ss_family) {
-    case AF_INET:
-        ipaddr = (struct sockaddr_in*) &addr;
-        memcpy(&((struct sockaddr_in *) &md5sig.tcpm_addr)->sin_addr, &ipaddr->sin_addr, sizeof(ipaddr->sin_addr));
-        break;
-    case AF_INET6:
-        ip6addr = (struct sockaddr_in6*) &addr;
-        memcpy(&((struct sockaddr_in6 *) &md5sig.tcpm_addr)->sin6_addr, &ip6addr->sin6_addr, sizeof(ip6addr->sin6_addr));
-        break;
-    }
-
-    if (key != NULL) {
-        md5sig.tcpm_keylen = (*env)->GetArrayLength(env, key);
-        (*env)->GetByteArrayRegion(env, key, 0, md5sig.tcpm_keylen, (void *) &md5sig.tcpm_key);
-        if ((*env)->ExceptionCheck(env) == JNI_TRUE) {
-            return;
-        }
-    }
-
-    if (setsockopt(fd, IPPROTO_TCP, TCP_MD5SIG, &md5sig, sizeof(md5sig)) < 0) {
-        netty_unix_errors_throwChannelExceptionErrorNo(env, "setsockopt() failed: ", errno);
-    }
-}
 // JNI Registered Methods End
 
 // JNI Method Registration Table Begin
@@ -759,10 +397,7 @@ static const JNINativeMethod statically_referenced_fixed_method_table[] = {
   { "epollout", "()I", (void *) netty_epoll_native_epollout },
   { "epollrdhup", "()I", (void *) netty_epoll_native_epollrdhup },
   { "epollerr", "()I", (void *) netty_epoll_native_epollerr },
-  { "ssizeMax", "()J", (void *) netty_epoll_native_ssizeMax },
   { "tcpMd5SigMaxKeyLen", "()I", (void *) netty_epoll_native_tcpMd5SigMaxKeyLen },
-  { "iovMax", "()I", (void *) netty_epoll_native_iovMax },
-  { "uioMaxIov", "()I", (void *) netty_epoll_native_uioMaxIov },
   { "isSupportingSendmmsg", "()Z", (void *) netty_epoll_native_isSupportingSendmmsg },
   { "isSupportingTcpFastopen", "()Z", (void *) netty_epoll_native_isSupportingTcpFastopen },
   { "kernelVersion", "()Ljava/lang/String;", (void *) netty_epoll_native_kernelVersion }
@@ -778,35 +413,10 @@ static const JNINativeMethod fixed_method_table[] = {
   { "epollCtlMod0", "(III)I", (void *) netty_epoll_native_epollCtlMod0 },
   { "epollCtlDel0", "(II)I", (void *) netty_epoll_native_epollCtlDel0 },
   // "sendmmsg0" has a dynamic signature
-  { "recvFd0", "(I)I", (void *) netty_epoll_native_recvFd0 },
-  { "sendFd0", "(II)I", (void *) netty_epoll_native_sendFd0 },
   // "sendFile0" has a dynamic signature
-  { "setReuseAddress", "(II)V", (void *) netty_epoll_native_setReuseAddress },
-  { "setReusePort", "(II)V", (void *) netty_epoll_native_setReusePort },
-  { "setTcpFastopen", "(II)V", (void *) netty_epoll_native_setTcpFastopen },
-  { "setTcpNotSentLowAt", "(II)V", (void *) netty_epoll_native_setTcpNotSentLowAt },
-  { "setTrafficClass", "(II)V", (void *) netty_epoll_native_setTrafficClass },
-  { "setBroadcast", "(II)V", (void *) netty_epoll_native_setBroadcast },
-  { "setTcpKeepIdle", "(II)V", (void *) netty_epoll_native_setTcpKeepIdle },
-  { "setTcpKeepIntvl", "(II)V", (void *) netty_epoll_native_setTcpKeepIntvl },
-  { "setTcpKeepCnt", "(II)V", (void *) netty_epoll_native_setTcpKeepCnt },
-  { "setTcpUserTimeout", "(II)V", (void *) netty_epoll_native_setTcpUserTimeout },
-  { "setIpFreeBind", "(II)V", (void *) netty_epoll_native_setIpFreeBind },
-  { "isReuseAddress", "(I)I", (void *) netty_epoll_native_isReuseAddress },
-  { "isReusePort", "(I)I", (void *) netty_epoll_native_isReusePort },
-  { "getTcpNotSentLowAt", "(I)I", (void *) netty_epoll_native_getTcpNotSentLowAt },
-  { "getTrafficClass", "(I)I", (void *) netty_epoll_native_getTrafficClass },
-  { "isBroadcast", "(I)I", (void *) netty_epoll_native_isBroadcast },
-  { "getTcpKeepIdle", "(I)I", (void *) netty_epoll_native_getTcpKeepIdle },
-  { "getTcpKeepIntvl", "(I)I", (void *) netty_epoll_native_getTcpKeepIntvl },
-  { "getTcpKeepCnt", "(I)I", (void *) netty_epoll_native_getTcpKeepCnt },
-  { "getTcpUserTimeout", "(I)I", (void *) netty_epoll_native_getTcpUserTimeout },
-  { "isIpFreeBind", "(I)I", (void *) netty_epoll_Native_isIpFreeBind },
-  { "tcpInfo0", "(I[I)V", (void *) netty_epoll_native_tcpInfo0 },
   { "sizeofEpollEvent", "()I", (void *) netty_epoll_native_sizeofEpollEvent },
   { "offsetofEpollData", "()I", (void *) netty_epoll_native_offsetofEpollData },
-  { "splice0", "(IJIJJ)I", (void *) netty_epoll_native_splice0 },
+  { "splice0", "(IJIJJ)I", (void *) netty_epoll_native_splice0 }
-  { "setTcpMd5Sig0", "(I[BI[B)V", (void *) netty_epoll_native_setTcpMd5Sig0 }
 };
 static const jint fixed_method_table_size = sizeof(fixed_method_table) / sizeof(fixed_method_table[0]);
 
@@ -823,6 +433,7 @@ static JNINativeMethod* createDynamicMethodsTable(const char* packagePrefix) {
     dynamicMethod->signature = netty_unix_util_prepend("(I[L", dynamicTypeName);
     dynamicMethod->fnPtr = (void *) netty_epoll_native_sendmmsg0;
     free(dynamicTypeName);
+
     ++dynamicMethod;
     dynamicTypeName = netty_unix_util_prepend(packagePrefix, "io/netty/channel/DefaultFileRegion;JJJ)J");
     dynamicMethod->name = "sendfile0";
@@ -864,6 +475,9 @@ static jint netty_epoll_native_JNI_OnLoad(JNIEnv* env, const char* packagePrefix
     freeDynamicMethodsTable(dynamicMethods);
     dynamicMethods = NULL;
     // Load all c modules that we depend upon
+    if (netty_unix_limits_JNI_OnLoad(env, packagePrefix) == JNI_ERR) {
+        return JNI_ERR;
+    }
     if (netty_unix_errors_JNI_OnLoad(env, packagePrefix) == JNI_ERR) {
         return JNI_ERR;
     }
@@ -873,6 +487,10 @@ static jint netty_epoll_native_JNI_OnLoad(JNIEnv* env, const char* packagePrefix
     if (netty_unix_socket_JNI_OnLoad(env, packagePrefix) == JNI_ERR) {
         return JNI_ERR;
     }
+    if (netty_epoll_linuxsocket_JNI_OnLoad(env, packagePrefix) == JNI_ERR) {
+        return JNI_ERR;
+    }
+
     // Initialize this module
     char* nettyClassName = netty_unix_util_prepend(packagePrefix, "io/netty/channel/DefaultFileRegion");
     jclass fileRegionCls = (*env)->FindClass(env, nettyClassName);
@@ -950,7 +568,8 @@ static jint netty_epoll_native_JNI_OnLoad(JNIEnv* env, const char* packagePrefix
         return JNI_ERR;
     }
 
-    if (!initializeEpollWaitClock()) {
+    if (!netty_unix_util_initialize_wait_clock(&waitClockId)) {
+      fprintf(stderr, "FATAL: could not find a clock for clock_gettime!\n");
       return JNI_ERR;
     }
 
@@ -958,49 +577,11 @@ static jint netty_epoll_native_JNI_OnLoad(JNIEnv* env, const char* packagePrefix
 }
 
 static void netty_epoll_native_JNI_OnUnLoad(JNIEnv* env) {
+    netty_unix_limits_JNI_OnUnLoad(env);
     netty_unix_errors_JNI_OnUnLoad(env);
     netty_unix_filedescriptor_JNI_OnUnLoad(env);
     netty_unix_socket_JNI_OnUnLoad(env);
-}
+    netty_epoll_linuxsocket_JNI_OnUnLoad(env);
-
-/**
- * The expected format of the library name is "lib<>netty-transport-native-epoll" where the <> portion is what we will return.
- */
-static char* parsePackagePrefix(const char* libraryPathName, jint* status) {
-    char* packageNameEnd = strstr(libraryPathName, "netty-transport-native-epoll");
-    if (packageNameEnd == NULL) {
-        *status = JNI_ERR;
-        return NULL;
-    }
-    char* packagePrefix = netty_unix_util_rstrstr(packageNameEnd, libraryPathName, "lib");
-    if (packagePrefix == NULL) {
-        *status = JNI_ERR;
-        return NULL;
-    }
-    packagePrefix += 3;
-    if (packagePrefix == packageNameEnd) {
-        return NULL;
-    }
-    // packagePrefix length is > 0
-    // Make a copy so we can modify the value without impacting libraryPathName.
-    size_t packagePrefixLen = packageNameEnd - packagePrefix;
-    packagePrefix = strndup(packagePrefix, packagePrefixLen);
-    // Make sure the packagePrefix is in the correct format for the JNI functions it will be used with.
-    char* temp = packagePrefix;
-    packageNameEnd = packagePrefix + packagePrefixLen;
-    // Package names must be sanitized, in JNI packages names are separated by '/' characters.
-    for (; temp != packageNameEnd; ++temp) {
-        if (*temp == '-') {
-            *temp = '/';
-        }
-    }
-    // Make sure packagePrefix is terminated with the '/' JNI package separator.
-    if(*(--temp) != '/') {
-        temp = packagePrefix;
-        packagePrefix = netty_unix_util_prepend(packagePrefix, "/");
-        free(temp);
-    }
-    return packagePrefix;
 }
 
 jint JNI_OnLoad(JavaVM* vm, void* reserved) {
@@ -1013,11 +594,11 @@ jint JNI_OnLoad(JavaVM* vm, void* reserved) {
     jint status = 0;
     // We need to use an address of a function that is uniquely part of this library, so choose a static
     // function. See https://github.com/netty/netty/issues/4840.
-    if (!dladdr((void*) parsePackagePrefix, &dlinfo)) {
+    if (!dladdr((void*) netty_epoll_native_JNI_OnUnLoad, &dlinfo)) {
         fprintf(stderr, "FATAL: transport-native-epoll JNI call to dladdr failed!\n");
         return JNI_ERR;
     }
-    char* packagePrefix = parsePackagePrefix(dlinfo.dli_fname, &status);
+    char* packagePrefix = netty_unix_util_parse_package_prefix(dlinfo.dli_fname, "netty-transport-native-epoll", &status);
     if (status == JNI_ERR) {
         fprintf(stderr, "FATAL: transport-native-epoll JNI encountered unexpected dlinfo.dli_fname: %s\n", dlinfo.dli_fname);
         return JNI_ERR;

transport-native-epoll/src/main/c/netty_unix_util.c

@@ -1,55 +0,0 @@
-/*
- * Copyright 2016 The Netty Project
- *
- * The Netty Project licenses this file to you under the Apache License,
- * version 2.0 (the "License"); you may not use this file except in compliance
- * with the License. You may obtain a copy of the License at:
- *
- *   http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
- * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
- * License for the specific language governing permissions and limitations
- * under the License.
- */
-
-#include <stdlib.h>
-#include <string.h>
-#include "netty_unix_util.h"
-
-char* netty_unix_util_prepend(const char* prefix, const char* str) {
-    if (prefix == NULL) {
-        char* result = (char*) malloc(sizeof(char) * (strlen(str) + 1));
-        strcpy(result, str);
-        return result;
-    }
-    char* result = (char*) malloc(sizeof(char) * (strlen(prefix) + strlen(str) + 1));
-    strcpy(result, prefix);
-    strcat(result, str);
-    return result;
-}
-
-char* netty_unix_util_rstrstr(char* s1rbegin, const char* s1rend, const char* s2) {
-    size_t s2len = strlen(s2);
-    char *s = s1rbegin - s2len;
-
-    for (; s >= s1rend; --s) {
-        if (strncmp(s, s2, s2len) == 0) {
-            return s;
-        }
-    }
-    return NULL;
-}
-
-jint netty_unix_util_register_natives(JNIEnv* env, const char* packagePrefix, const char* className, const JNINativeMethod* methods, jint numMethods) {
-    char* nettyClassName = netty_unix_util_prepend(packagePrefix, className);
-    jclass nativeCls = (*env)->FindClass(env, nettyClassName);
-    free(nettyClassName);
-    nettyClassName = NULL;
-    if (nativeCls == NULL) {
-        return JNI_ERR;
-    }
-
-    return (*env)->RegisterNatives(env, nativeCls, methods, numMethods);
-}

transport-native-epoll/src/main/java/io/netty/channel/epoll/AbstractEpollChannel.java

@@ -28,6 +28,7 @@ import io.netty.channel.EventLoop;
 import io.netty.channel.RecvByteBufAllocator;
 import io.netty.channel.socket.ChannelInputShutdownEvent;
 import io.netty.channel.socket.ChannelInputShutdownReadComplete;
+import io.netty.channel.unix.FileDescriptor;
 import io.netty.channel.unix.Socket;
 import io.netty.channel.unix.UnixChannel;
 import io.netty.util.ReferenceCountUtil;
@@ -43,20 +44,20 @@ import static io.netty.util.internal.ObjectUtil.checkNotNull;
 abstract class AbstractEpollChannel extends AbstractChannel implements UnixChannel {
     private static final ChannelMetadata METADATA = new ChannelMetadata(false);
     private final int readFlag;
-    private final Socket fileDescriptor;
+    final LinuxSocket socket;
     protected int flags = Native.EPOLLET;
     boolean inputClosedSeenErrorOnRead;
     boolean epollInReadyRunnablePending;
 
     protected volatile boolean active;
 
-    AbstractEpollChannel(Socket fd, int flag) {
+    AbstractEpollChannel(LinuxSocket fd, int flag) {
         this(null, fd, flag, false);
     }
 
-    AbstractEpollChannel(Channel parent, Socket fd, int flag, boolean active) {
+    AbstractEpollChannel(Channel parent, LinuxSocket fd, int flag, boolean active) {
         super(parent);
-        fileDescriptor = checkNotNull(fd, "fd");
+        socket = checkNotNull(fd, "fd");
         readFlag = flag;
         flags |= flag;
         this.active = active;
@@ -89,8 +90,8 @@ abstract class AbstractEpollChannel extends AbstractChannel implements UnixChann
     }
 
     @Override
-    public final Socket fd() {
+    public final FileDescriptor fd() {
-        return fileDescriptor;
+        return socket;
     }
 
     @Override
@@ -115,7 +116,7 @@ abstract class AbstractEpollChannel extends AbstractChannel implements UnixChann
         try {
             doDeregister();
         } finally {
-            fileDescriptor.close();
+            socket.close();
         }
     }
 
@@ -131,7 +132,7 @@ abstract class AbstractEpollChannel extends AbstractChannel implements UnixChann
 
     @Override
     public boolean isOpen() {
-        return fileDescriptor.isOpen();
+        return socket.isOpen();
     }
 
     @Override
@@ -158,7 +159,7 @@ abstract class AbstractEpollChannel extends AbstractChannel implements UnixChann
     }
 
     final boolean shouldBreakEpollInReady(ChannelConfig config) {
-        return fileDescriptor.isInputShutdown() && (inputClosedSeenErrorOnRead || !isAllowHalfClosure(config));
+        return socket.isInputShutdown() && (inputClosedSeenErrorOnRead || !isAllowHalfClosure(config));
     }
 
     final boolean isAllowHalfClosure(ChannelConfig config) {
@@ -265,10 +266,10 @@ abstract class AbstractEpollChannel extends AbstractChannel implements UnixChann
         int localReadAmount;
         unsafe().recvBufAllocHandle().attemptedBytesRead(byteBuf.writableBytes());
         if (byteBuf.hasMemoryAddress()) {
-            localReadAmount = fileDescriptor.readAddress(byteBuf.memoryAddress(), writerIndex, byteBuf.capacity());
+            localReadAmount = socket.readAddress(byteBuf.memoryAddress(), writerIndex, byteBuf.capacity());
         } else {
             ByteBuffer buf = byteBuf.internalNioBuffer(writerIndex, byteBuf.writableBytes());
-            localReadAmount = fileDescriptor.read(buf, buf.position(), buf.limit());
+            localReadAmount = socket.read(buf, buf.position(), buf.limit());
         }
         if (localReadAmount > 0) {
             byteBuf.writerIndex(writerIndex + localReadAmount);
@@ -283,8 +284,8 @@ abstract class AbstractEpollChannel extends AbstractChannel implements UnixChann
             long memoryAddress = buf.memoryAddress();
             int readerIndex = buf.readerIndex();
             int writerIndex = buf.writerIndex();
-            for (int i = writeSpinCount - 1; i >= 0; i--) {
+            for (int i = writeSpinCount; i > 0; --i) {
-                int localFlushedAmount = fileDescriptor.writeAddress(memoryAddress, readerIndex, writerIndex);
+                int localFlushedAmount = socket.writeAddress(memoryAddress, readerIndex, writerIndex);
                 if (localFlushedAmount > 0) {
                     writtenBytes += localFlushedAmount;
                     if (writtenBytes == readableBytes) {
@@ -302,10 +303,10 @@ abstract class AbstractEpollChannel extends AbstractChannel implements UnixChann
             } else {
                 nioBuf = buf.nioBuffer();
             }
-            for (int i = writeSpinCount - 1; i >= 0; i--) {
+            for (int i = writeSpinCount; i > 0; --i) {
                 int pos = nioBuf.position();
                 int limit = nioBuf.limit();
-                int localFlushedAmount = fileDescriptor.write(nioBuf, pos, limit);
+                int localFlushedAmount = socket.write(nioBuf, pos, limit);
                 if (localFlushedAmount > 0) {
                     nioBuf.position(pos + localFlushedAmount);
                     writtenBytes += localFlushedAmount;
@@ -410,10 +411,10 @@ abstract class AbstractEpollChannel extends AbstractChannel implements UnixChann
          * Shutdown the input side of the channel.
          */
         void shutdownInput(boolean rdHup) {
-            if (!fd().isInputShutdown()) {
+            if (!socket.isInputShutdown()) {
                 if (isAllowHalfClosure(config())) {
                     try {
-                        fd().shutdown(true, false);
+                        socket.shutdown(true, false);
                     } catch (IOException ignored) {
                         // We attempted to shutdown and failed, which means the input has already effectively been
                         // shutdown.
@@ -422,9 +423,8 @@ abstract class AbstractEpollChannel extends AbstractChannel implements UnixChann
                     } catch (NotYetConnectedException ignore) {
                         // We attempted to shutdown and failed, which means the input has already effectively been
                         // shutdown.
-                        fireEventAndClose(ChannelInputShutdownEvent.INSTANCE);
-                        return;
                     }
+                    clearEpollIn();
                     pipeline().fireUserEventTriggered(ChannelInputShutdownEvent.INSTANCE);
                 } else {
                     close(voidPromise());
@@ -471,7 +471,7 @@ abstract class AbstractEpollChannel extends AbstractChannel implements UnixChann
          * Called once a EPOLLOUT event is ready to be processed
          */
         void epollOutReady() {
-            if (fd().isOutputShutdown()) {
+            if (socket.isOutputShutdown()) {
                 return;
             }
             // directly call super.flush0() to force a flush now

transport-native-epoll/src/main/java/io/netty/channel/epoll/AbstractEpollServerChannel.java

@@ -23,8 +23,6 @@ import io.netty.channel.ChannelPipeline;
 import io.netty.channel.ChannelPromise;
 import io.netty.channel.EventLoop;
 import io.netty.channel.ServerChannel;
-import io.netty.channel.unix.FileDescriptor;
-import io.netty.channel.unix.Socket;
 
 import java.net.InetSocketAddress;
 import java.net.SocketAddress;
@@ -32,31 +30,15 @@ import java.net.SocketAddress;
 public abstract class AbstractEpollServerChannel extends AbstractEpollChannel implements ServerChannel {
     private static final ChannelMetadata METADATA = new ChannelMetadata(false, 16);
 
-    /**
-     * @deprecated Use {@link #AbstractEpollServerChannel(Socket, boolean)}.
-     */
-    @Deprecated
     protected AbstractEpollServerChannel(int fd) {
-        this(new Socket(fd), false);
+        this(new LinuxSocket(fd), false);
     }
 
-    /**
+    AbstractEpollServerChannel(LinuxSocket fd) {
-     * @deprecated Use {@link #AbstractEpollServerChannel(Socket, boolean)}.
-     */
-    @Deprecated
-    protected AbstractEpollServerChannel(FileDescriptor fd) {
-        this(new Socket(fd.intValue()));
-    }
-
-    /**
-     * @deprecated Use {@link #AbstractEpollServerChannel(Socket, boolean)}.
-     */
-    @Deprecated
-    protected AbstractEpollServerChannel(Socket fd) {
         this(fd, isSoErrorZero(fd));
     }
 
-    protected AbstractEpollServerChannel(Socket fd, boolean active) {
+    AbstractEpollServerChannel(LinuxSocket fd, boolean active) {
         super(null, fd, Native.EPOLLIN, active);
     }
 
@@ -117,6 +99,7 @@ public abstract class AbstractEpollServerChannel extends AbstractEpollChannel im
 
             final ChannelPipeline pipeline = pipeline();
             allocHandle.reset(config);
+            allocHandle.attemptedBytesRead(1);
             epollInBefore();
 
             Throwable exception = null;
@@ -126,16 +109,16 @@ public abstract class AbstractEpollServerChannel extends AbstractEpollChannel im
                         // lastBytesRead represents the fd. We use lastBytesRead because it must be set so that the
                         // EpollRecvByteAllocatorHandle knows if it should try to read again or not when autoRead is
                         // enabled.
-                        allocHandle.lastBytesRead(fd().accept(acceptedAddress));
+                        allocHandle.lastBytesRead(socket.accept(acceptedAddress));
                         if (allocHandle.lastBytesRead() == -1) {
                             // this means everything was handled for now
                             break;
                         }
                         allocHandle.incMessagesRead(1);
 
-                        int len = acceptedAddress[0];
                         readPending = false;
-                        pipeline.fireChannelRead(newChildChannel(allocHandle.lastBytesRead(), acceptedAddress, 1, len));
+                        pipeline.fireChannelRead(newChildChannel(allocHandle.lastBytesRead(), acceptedAddress, 1,
+                                                                 acceptedAddress[0]));
                     } while (allocHandle.continueReading());
                 } catch (Throwable t) {
                     exception = t;

transport-native-epoll/src/main/java/io/netty/channel/epoll/AbstractEpollStreamChannel.java

@@ -17,9 +17,7 @@ package io.netty.channel.epoll;
 
 import io.netty.buffer.ByteBuf;
 import io.netty.buffer.ByteBufAllocator;
-import io.netty.buffer.ByteBufUtil;
 import io.netty.buffer.CompositeByteBuf;
-import io.netty.buffer.Unpooled;
 import io.netty.channel.Channel;
 import io.netty.channel.ChannelConfig;
 import io.netty.channel.ChannelFuture;
@@ -35,7 +33,8 @@ import io.netty.channel.FileRegion;
 import io.netty.channel.RecvByteBufAllocator;
 import io.netty.channel.socket.DuplexChannel;
 import io.netty.channel.unix.FileDescriptor;
-import io.netty.channel.unix.Socket;
+import io.netty.channel.unix.IovArray;
+import io.netty.channel.unix.SocketWritableByteChannel;
 import io.netty.util.internal.PlatformDependent;
 import io.netty.util.internal.StringUtil;
 import io.netty.util.internal.ThrowableUtil;
@@ -54,6 +53,7 @@ import java.util.concurrent.ScheduledFuture;
 import java.util.concurrent.TimeUnit;
 
 import static io.netty.channel.unix.FileDescriptor.pipe;
+import static io.netty.channel.unix.Limits.IOV_MAX;
 import static io.netty.util.internal.ObjectUtil.checkNotNull;
 
 public abstract class AbstractEpollStreamChannel extends AbstractEpollChannel implements DuplexChannel {
@@ -89,45 +89,25 @@ public abstract class AbstractEpollStreamChannel extends AbstractEpollChannel im
 
     private WritableByteChannel byteChannel;
 
-    /**
-     * @deprecated Use {@link #AbstractEpollStreamChannel(Channel, Socket)}.
-     */
-    @Deprecated
     protected AbstractEpollStreamChannel(Channel parent, int fd) {
-        this(parent, new Socket(fd));
+        this(parent, new LinuxSocket(fd));
     }
 
-    /**
-     * @deprecated Use {@link #AbstractEpollStreamChannel(Socket, boolean)}.
-     */
-    @Deprecated
     protected AbstractEpollStreamChannel(int fd) {
-        this(new Socket(fd));
+        this(new LinuxSocket(fd));
     }
 
-    /**
+    AbstractEpollStreamChannel(LinuxSocket fd) {
-     * @deprecated Use {@link #AbstractEpollStreamChannel(Socket, boolean)}.
-     */
-    @Deprecated
-    protected AbstractEpollStreamChannel(FileDescriptor fd) {
-        this(new Socket(fd.intValue()));
-    }
-
-    /**
-     * @deprecated Use {@link #AbstractEpollStreamChannel(Socket, boolean)}.
-     */
-    @Deprecated
-    protected AbstractEpollStreamChannel(Socket fd) {
         this(fd, isSoErrorZero(fd));
     }
 
-    protected AbstractEpollStreamChannel(Channel parent, Socket fd) {
+    AbstractEpollStreamChannel(Channel parent, LinuxSocket fd) {
         super(parent, fd, Native.EPOLLIN, true);
         // Add EPOLLRDHUP so we are notified once the remote peer close the connection.
         flags |= Native.EPOLLRDHUP;
     }
 
-    protected AbstractEpollStreamChannel(Socket fd, boolean active) {
+    protected AbstractEpollStreamChannel(LinuxSocket fd, boolean active) {
         super(null, fd, Native.EPOLLIN, active);
         // Add EPOLLRDHUP so we are notified once the remote peer close the connection.
         flags |= Native.EPOLLRDHUP;
@@ -301,8 +281,8 @@ public abstract class AbstractEpollStreamChannel extends AbstractEpollChannel im
         boolean done = false;
         int offset = 0;
         int end = offset + cnt;
-        for (int i = writeSpinCount - 1; i >= 0; i--) {
+        for (int i = writeSpinCount; i > 0; --i) {
-            long localWrittenBytes = fd().writevAddresses(array.memoryAddress(offset), cnt);
+            long localWrittenBytes = socket.writevAddresses(array.memoryAddress(offset), cnt);
             if (localWrittenBytes == 0) {
                 break;
             }
@@ -340,8 +320,8 @@ public abstract class AbstractEpollStreamChannel extends AbstractEpollChannel im
         boolean done = false;
         int offset = 0;
         int end = offset + nioBufferCnt;
-        for (int i = writeSpinCount - 1; i >= 0; i--) {
+        for (int i = writeSpinCount; i > 0; --i) {
-            long localWrittenBytes = fd().writev(nioBuffers, offset, nioBufferCnt);
+            long localWrittenBytes = socket.writev(nioBuffers, offset, nioBufferCnt);
             if (localWrittenBytes == 0) {
                 break;
             }
@@ -390,10 +370,10 @@ public abstract class AbstractEpollStreamChannel extends AbstractEpollChannel im
         boolean done = false;
         long flushedAmount = 0;
 
-        for (int i = writeSpinCount - 1; i >= 0; i--) {
+        for (int i = writeSpinCount; i > 0; --i) {
             final long offset = region.transferred();
             final long localFlushedAmount =
-                    Native.sendfile(fd().intValue(), region, baseOffset, offset, regionCount - offset);
+                    Native.sendfile(socket.intValue(), region, baseOffset, offset, regionCount - offset);
             if (localFlushedAmount == 0) {
                 break;
             }
@@ -426,9 +406,9 @@ public abstract class AbstractEpollStreamChannel extends AbstractEpollChannel im
         long flushedAmount = 0;
 
         if (byteChannel == null) {
-            byteChannel = new SocketWritableByteChannel();
+            byteChannel = new EpollSocketWritableByteChannel();
         }
-        for (int i = writeSpinCount - 1; i >= 0; i--) {
+        for (int i = writeSpinCount; i > 0; --i) {
             final long localFlushedAmount = region.transferTo(byteChannel, region.transferred());
             if (localFlushedAmount == 0) {
                 break;
@@ -564,7 +544,7 @@ public abstract class AbstractEpollStreamChannel extends AbstractEpollChannel im
                     // Special handling of CompositeByteBuf to reduce memory copies if some of the Components
                     // in the CompositeByteBuf are backed by a memoryAddress.
                     CompositeByteBuf comp = (CompositeByteBuf) buf;
-                    if (!comp.isDirect() || comp.nioBufferCount() > Native.IOV_MAX) {
+                    if (!comp.isDirect() || comp.nioBufferCount() > IOV_MAX) {
                         // more then 1024 buffers for gathering writes so just do a memory copy.
                         buf = newDirectBuffer(buf);
                         assert buf.hasMemoryAddress();
@@ -589,7 +569,7 @@ public abstract class AbstractEpollStreamChannel extends AbstractEpollChannel im
 
     private void shutdownOutput0(final ChannelPromise promise) {
         try {
-            fd().shutdown(false, true);
+            socket.shutdown(false, true);
             promise.setSuccess();
         } catch (Throwable cause) {
             promise.setFailure(cause);
@@ -598,7 +578,7 @@ public abstract class AbstractEpollStreamChannel extends AbstractEpollChannel im
 
     private void shutdownInput0(final ChannelPromise promise) {
         try {
-            fd().shutdown(true, false);
+            socket.shutdown(true, false);
             promise.setSuccess();
         } catch (Throwable cause) {
             promise.setFailure(cause);
@@ -607,7 +587,7 @@ public abstract class AbstractEpollStreamChannel extends AbstractEpollChannel im
 
     private void shutdown0(final ChannelPromise promise) {
         try {
-            fd().shutdown(true, true);
+            socket.shutdown(true, true);
             promise.setSuccess();
         } catch (Throwable cause) {
             promise.setFailure(cause);
@@ -616,17 +596,17 @@ public abstract class AbstractEpollStreamChannel extends AbstractEpollChannel im
 
     @Override
     public boolean isOutputShutdown() {
-        return fd().isOutputShutdown();
+        return socket.isOutputShutdown();
     }
 
     @Override
     public boolean isInputShutdown() {
-        return fd().isInputShutdown();
+        return socket.isInputShutdown();
     }
 
     @Override
     public boolean isShutdown() {
-        return fd().isShutdown();
+        return socket.isShutdown();
     }
 
     @Override
@@ -764,12 +744,12 @@ public abstract class AbstractEpollStreamChannel extends AbstractEpollChannel im
      */
     protected boolean doConnect(SocketAddress remoteAddress, SocketAddress localAddress) throws Exception {
         if (localAddress != null) {
-            fd().bind(localAddress);
+            socket.bind(localAddress);
         }
 
         boolean success = false;
         try {
-            boolean connected = fd().connect(remoteAddress);
+            boolean connected = socket.connect(remoteAddress);
             if (!connected) {
                 setFlag(Native.EPOLLOUT);
             }
@@ -952,7 +932,7 @@ public abstract class AbstractEpollStreamChannel extends AbstractEpollChannel im
          * Finish the connect
          */
         boolean doFinishConnect() throws Exception {
-            if (fd().finishConnect()) {
+            if (socket.finishConnect()) {
                 clearFlag(Native.EPOLLOUT);
                 return true;
             } else {
@@ -1085,7 +1065,7 @@ public abstract class AbstractEpollStreamChannel extends AbstractEpollChannel im
             int splicedIn = 0;
             for (;;) {
                 // Splicing until there is nothing left to splice.
-                int localSplicedIn = Native.splice(fd().intValue(), -1, pipeOut.intValue(), -1, length);
+                int localSplicedIn = Native.splice(socket.intValue(), -1, pipeOut.intValue(), -1, length);
                 if (localSplicedIn == 0) {
                     break;
                 }
@@ -1185,7 +1165,7 @@ public abstract class AbstractEpollStreamChannel extends AbstractEpollChannel im
         public boolean spliceOut() throws Exception {
             assert ch.eventLoop().inEventLoop();
             try {
-                int splicedOut = Native.splice(ch.pipeIn.intValue(), -1, ch.fd().intValue(), -1, len);
+                int splicedOut = Native.splice(ch.pipeIn.intValue(), -1, ch.socket.intValue(), -1, len);
                 len -= splicedOut;
                 if (len == 0) {
                     if (autoRead) {
@@ -1257,55 +1237,14 @@ public abstract class AbstractEpollStreamChannel extends AbstractEpollChannel im
         }
     }
 
-    private final class SocketWritableByteChannel implements WritableByteChannel {
+    private final class EpollSocketWritableByteChannel extends SocketWritableByteChannel {
-
+        EpollSocketWritableByteChannel() {
-        @Override
+            super(socket);
-        public int write(ByteBuffer src) throws IOException {
-            final int written;
-            int position = src.position();
-            int limit = src.limit();
-            if (src.isDirect()) {
-                written = fd().write(src, position, src.limit());
-            } else {
-                final int readableBytes = limit - position;
-                ByteBuf buffer = null;
-                try {
-                    if (readableBytes == 0) {
-                        buffer = Unpooled.EMPTY_BUFFER;
-                    } else {
-                        final ByteBufAllocator alloc = alloc();
-                        if (alloc.isDirectBufferPooled()) {
-                            buffer = alloc.directBuffer(readableBytes);
-                        } else {
-                            buffer = ByteBufUtil.threadLocalDirectBuffer();
-                            if (buffer == null) {
-                                buffer = Unpooled.directBuffer(readableBytes);
-                            }
-                        }
-                    }
-                    buffer.writeBytes(src.duplicate());
-                    ByteBuffer nioBuffer = buffer.internalNioBuffer(buffer.readerIndex(), readableBytes);
-                    written = fd().write(nioBuffer, nioBuffer.position(), nioBuffer.limit());
-                } finally {
-                    if (buffer != null) {
-                        buffer.release();
-                    }
-                }
-            }
-            if (written > 0) {
-                src.position(position + written);
-            }
-            return written;
         }
 
         @Override
-        public boolean isOpen() {
+        protected ByteBufAllocator alloc() {
-            return fd().isOpen();
+            return AbstractEpollStreamChannel.this.alloc();
-        }
-
-        @Override
-        public void close() throws IOException {
-            fd().close();
         }
     }
 }

transport-native-epoll/src/main/java/io/netty/channel/epoll/EpollChannelConfig.java

@@ -22,7 +22,6 @@ import io.netty.channel.DefaultChannelConfig;
 import io.netty.channel.MessageSizeEstimator;
 import io.netty.channel.RecvByteBufAllocator;
 import io.netty.channel.WriteBufferWaterMark;
-
 import java.io.IOException;
 import java.util.Map;
 

transport-native-epoll/src/main/java/io/netty/channel/epoll/EpollChannelOption.java

@@ -16,15 +16,13 @@
 package io.netty.channel.epoll;
 
 import io.netty.channel.ChannelOption;
-import io.netty.channel.unix.DomainSocketReadMode;
+import io.netty.channel.unix.UnixChannelOption;
-
 import java.net.InetAddress;
 import java.util.Map;
 
-public final class EpollChannelOption<T> extends ChannelOption<T> {
+public final class EpollChannelOption<T> extends UnixChannelOption<T> {
 
     public static final ChannelOption<Boolean> TCP_CORK = valueOf(EpollChannelOption.class, "TCP_CORK");
-    public static final ChannelOption<Boolean> SO_REUSEPORT = valueOf(EpollChannelOption.class, "SO_REUSEPORT");
     public static final ChannelOption<Long> TCP_NOTSENT_LOWAT = valueOf(EpollChannelOption.class, "TCP_NOTSENT_LOWAT");
     public static final ChannelOption<Integer> TCP_KEEPIDLE = valueOf(EpollChannelOption.class, "TCP_KEEPIDLE");
     public static final ChannelOption<Integer> TCP_KEEPINTVL = valueOf(EpollChannelOption.class, "TCP_KEEPINTVL");
@@ -37,8 +35,6 @@ public final class EpollChannelOption<T> extends ChannelOption<T> {
             ChannelOption.valueOf(EpollChannelOption.class, "TCP_DEFER_ACCEPT");
     public static final ChannelOption<Boolean> TCP_QUICKACK = valueOf(EpollChannelOption.class, "TCP_QUICKACK");
 
-    public static final ChannelOption<DomainSocketReadMode> DOMAIN_SOCKET_READ_MODE =
-            ChannelOption.valueOf(EpollChannelOption.class, "DOMAIN_SOCKET_READ_MODE");
     public static final ChannelOption<EpollMode> EPOLL_MODE =
             ChannelOption.valueOf(EpollChannelOption.class, "EPOLL_MODE");
 
@@ -46,6 +42,5 @@ public final class EpollChannelOption<T> extends ChannelOption<T> {
 
     @SuppressWarnings({ "unused", "deprecation" })
     private EpollChannelOption() {
-        super(null);
     }
 }

transport-native-epoll/src/main/java/io/netty/channel/epoll/EpollDatagramChannel.java

@@ -29,8 +29,7 @@ import io.netty.channel.socket.DatagramChannel;
 import io.netty.channel.socket.DatagramChannelConfig;
 import io.netty.channel.socket.DatagramPacket;
 import io.netty.channel.unix.DatagramSocketAddress;
-import io.netty.channel.unix.FileDescriptor;
+import io.netty.channel.unix.IovArray;
-import io.netty.channel.unix.Socket;
 import io.netty.util.internal.PlatformDependent;
 import io.netty.util.internal.StringUtil;
 
@@ -45,7 +44,8 @@ import java.nio.channels.NotYetConnectedException;
 import java.util.ArrayList;
 import java.util.List;
 
-import static io.netty.channel.unix.Socket.newSocketDgram;
+import static io.netty.channel.epoll.LinuxSocket.newSocketDgram;
+import static io.netty.channel.unix.Limits.IOV_MAX;
 
 /**
  * {@link DatagramChannel} implementation that uses linux EPOLL Edge-Triggered Mode for
@@ -70,15 +70,11 @@ public final class EpollDatagramChannel extends AbstractEpollChannel implements
         config = new EpollDatagramChannelConfig(this);
     }
 
-    /**
+    public EpollDatagramChannel(int fd) {
-     * @deprecated Use {@link #EpollDatagramChannel(Socket)}.
+        this(new LinuxSocket(fd));
-     */
-    @Deprecated
-    public EpollDatagramChannel(FileDescriptor fd) {
-        this(new Socket(fd.intValue()));
     }
 
-    public EpollDatagramChannel(Socket fd) {
+    EpollDatagramChannel(LinuxSocket fd) {
         super(null, fd, Native.EPOLLIN, true);
         // As we create an EpollDatagramChannel from a FileDescriptor we should try to obtain the remote and local
         // address from it. This is needed as the FileDescriptor may be bound already.
@@ -104,7 +100,7 @@ public final class EpollDatagramChannel extends AbstractEpollChannel implements
     @Override
     @SuppressWarnings("deprecation")
     public boolean isActive() {
-        return fd().isOpen() && (config.getActiveOnOpen() && isRegistered() || active);
+        return socket.isOpen() && (config.getActiveOnOpen() && isRegistered() || active);
     }
 
     @Override
@@ -280,8 +276,8 @@ public final class EpollDatagramChannel extends AbstractEpollChannel implements
     protected void doBind(SocketAddress localAddress) throws Exception {
         InetSocketAddress addr = (InetSocketAddress) localAddress;
         checkResolvable(addr);
-        fd().bind(addr);
+        socket.bind(addr);
-        local = fd().localAddress();
+        local = socket.localAddress();
         active = true;
     }
 
@@ -307,7 +303,7 @@ public final class EpollDatagramChannel extends AbstractEpollChannel implements
                         NativeDatagramPacketArray.NativeDatagramPacket[] packets = array.packets();
 
                         while (cnt > 0) {
-                            int send = Native.sendmmsg(fd().intValue(), packets, offset, cnt);
+                            int send = Native.sendmmsg(socket.intValue(), packets, offset, cnt);
                             if (send == 0) {
                                 // Did not write all messages.
                                 setFlag(Native.EPOLLOUT);
@@ -323,7 +319,7 @@ public final class EpollDatagramChannel extends AbstractEpollChannel implements
                     }
                 }
                 boolean done = false;
-                for (int i = config().getWriteSpinCount() - 1; i >= 0; i--) {
+                for (int i = config().getWriteSpinCount(); i > 0; --i) {
                     if (doWriteMessage(msg)) {
                         done = true;
                         break;
@@ -375,7 +371,7 @@ public final class EpollDatagramChannel extends AbstractEpollChannel implements
         final int writtenBytes;
         if (data.hasMemoryAddress()) {
             long memoryAddress = data.memoryAddress();
-            writtenBytes = fd().sendToAddress(memoryAddress, data.readerIndex(), data.writerIndex(),
+            writtenBytes = socket.sendToAddress(memoryAddress, data.readerIndex(), data.writerIndex(),
                     remoteAddress.getAddress(), remoteAddress.getPort());
         } else if (data instanceof CompositeByteBuf) {
             IovArray array = ((EpollEventLoop) eventLoop()).cleanArray();
@@ -383,11 +379,11 @@ public final class EpollDatagramChannel extends AbstractEpollChannel implements
             int cnt = array.count();
             assert cnt != 0;
 
-            writtenBytes = fd().sendToAddresses(array.memoryAddress(0),
+            writtenBytes = socket.sendToAddresses(array.memoryAddress(0),
                     cnt, remoteAddress.getAddress(), remoteAddress.getPort());
         } else  {
             ByteBuffer nioData = data.internalNioBuffer(data.readerIndex(), data.readableBytes());
-            writtenBytes = fd().sendTo(nioData, nioData.position(), nioData.limit(),
+            writtenBytes = socket.sendTo(nioData, nioData.position(), nioData.limit(),
                     remoteAddress.getAddress(), remoteAddress.getPort());
         }
 
@@ -407,7 +403,7 @@ public final class EpollDatagramChannel extends AbstractEpollChannel implements
                 // Special handling of CompositeByteBuf to reduce memory copies if some of the Components
                 // in the CompositeByteBuf are backed by a memoryAddress.
                 CompositeByteBuf comp = (CompositeByteBuf) content;
-                if (comp.isDirect() && comp.nioBufferCount() <= Native.IOV_MAX) {
+                if (comp.isDirect() && comp.nioBufferCount() <= IOV_MAX) {
                     return msg;
                 }
             }
@@ -423,7 +419,7 @@ public final class EpollDatagramChannel extends AbstractEpollChannel implements
                     // Special handling of CompositeByteBuf to reduce memory copies if some of the Components
                     // in the CompositeByteBuf are backed by a memoryAddress.
                     CompositeByteBuf comp = (CompositeByteBuf) buf;
-                    if (!comp.isDirect() || comp.nioBufferCount() > Native.IOV_MAX) {
+                    if (!comp.isDirect() || comp.nioBufferCount() > IOV_MAX) {
                         // more then 1024 buffers for gathering writes so just do a memory copy.
                         buf = newDirectBuffer(buf);
                         assert buf.hasMemoryAddress();
@@ -452,7 +448,7 @@ public final class EpollDatagramChannel extends AbstractEpollChannel implements
                     // Special handling of CompositeByteBuf to reduce memory copies if some of the Components
                     // in the CompositeByteBuf are backed by a memoryAddress.
                     CompositeByteBuf comp = (CompositeByteBuf) content;
-                    if (comp.isDirect() && comp.nioBufferCount() <= Native.IOV_MAX) {
+                    if (comp.isDirect() && comp.nioBufferCount() <= IOV_MAX) {
                         return e;
                     }
                 }
@@ -494,7 +490,7 @@ public final class EpollDatagramChannel extends AbstractEpollChannel implements
 
                     checkResolvable(remoteAddress);
                     EpollDatagramChannel.this.remote = remoteAddress;
-                    EpollDatagramChannel.this.local = fd().localAddress();
+                    EpollDatagramChannel.this.local = socket.localAddress();
                     success = true;
 
                     // First notify the promise before notifying the handler.
@@ -543,11 +539,11 @@ public final class EpollDatagramChannel extends AbstractEpollChannel implements
                         final DatagramSocketAddress remoteAddress;
                         if (data.hasMemoryAddress()) {
                             // has a memory address so use optimized call
-                            remoteAddress = fd().recvFromAddress(data.memoryAddress(), data.writerIndex(),
+                            remoteAddress = socket.recvFromAddress(data.memoryAddress(), data.writerIndex(),
                                                                  data.capacity());
                         } else {
                             ByteBuffer nioData = data.internalNioBuffer(data.writerIndex(), data.writableBytes());
-                            remoteAddress = fd().recvFrom(nioData, nioData.position(), nioData.limit());
+                            remoteAddress = socket.recvFrom(nioData, nioData.position(), nioData.limit());
                         }
 
                         if (remoteAddress == null) {

transport-native-epoll/src/main/java/io/netty/channel/epoll/EpollDatagramChannelConfig.java

@@ -23,7 +23,6 @@ import io.netty.channel.MessageSizeEstimator;
 import io.netty.channel.RecvByteBufAllocator;
 import io.netty.channel.WriteBufferWaterMark;
 import io.netty.channel.socket.DatagramChannelConfig;
-
 import java.io.IOException;
 import java.net.InetAddress;
 import java.net.NetworkInterface;
@@ -208,7 +207,7 @@ public final class EpollDatagramChannelConfig extends EpollChannelConfig impleme
     @Override
     public int getSendBufferSize() {
         try {
-            return datagramChannel.fd().getSendBufferSize();
+            return datagramChannel.socket.getSendBufferSize();
         } catch (IOException e) {
             throw new ChannelException(e);
         }
@@ -217,7 +216,7 @@ public final class EpollDatagramChannelConfig extends EpollChannelConfig impleme
     @Override
     public EpollDatagramChannelConfig setSendBufferSize(int sendBufferSize) {
         try {
-            datagramChannel.fd().setSendBufferSize(sendBufferSize);
+            datagramChannel.socket.setSendBufferSize(sendBufferSize);
             return this;
         } catch (IOException e) {
             throw new ChannelException(e);
@@ -227,7 +226,7 @@ public final class EpollDatagramChannelConfig extends EpollChannelConfig impleme
     @Override
     public int getReceiveBufferSize() {
         try {
-            return datagramChannel.fd().getReceiveBufferSize();
+            return datagramChannel.socket.getReceiveBufferSize();
         } catch (IOException e) {
             throw new ChannelException(e);
         }
@@ -236,7 +235,7 @@ public final class EpollDatagramChannelConfig extends EpollChannelConfig impleme
     @Override
     public EpollDatagramChannelConfig setReceiveBufferSize(int receiveBufferSize) {
         try {
-            datagramChannel.fd().setReceiveBufferSize(receiveBufferSize);
+            datagramChannel.socket.setReceiveBufferSize(receiveBufferSize);
             return this;
         } catch (IOException e) {
             throw new ChannelException(e);
@@ -246,7 +245,7 @@ public final class EpollDatagramChannelConfig extends EpollChannelConfig impleme
     @Override
     public int getTrafficClass() {
         try {
-            return Native.getTrafficClass(datagramChannel.fd().intValue());
+            return datagramChannel.socket.getTrafficClass();
         } catch (IOException e) {
             throw new ChannelException(e);
         }
@@ -255,7 +254,7 @@ public final class EpollDatagramChannelConfig extends EpollChannelConfig impleme
     @Override
     public EpollDatagramChannelConfig setTrafficClass(int trafficClass) {
         try {
-            Native.setTrafficClass(datagramChannel.fd().intValue(), trafficClass);
+            datagramChannel.socket.setTrafficClass(trafficClass);
             return this;
         } catch (IOException e) {
             throw new ChannelException(e);
@@ -265,7 +264,7 @@ public final class EpollDatagramChannelConfig extends EpollChannelConfig impleme
     @Override
     public boolean isReuseAddress() {
         try {
-            return Native.isReuseAddress(datagramChannel.fd().intValue()) == 1;
+            return datagramChannel.socket.isReuseAddress();
         } catch (IOException e) {
             throw new ChannelException(e);
         }
@@ -274,7 +273,7 @@ public final class EpollDatagramChannelConfig extends EpollChannelConfig impleme
     @Override
     public EpollDatagramChannelConfig setReuseAddress(boolean reuseAddress) {
         try {
-            Native.setReuseAddress(datagramChannel.fd().intValue(), reuseAddress ? 1 : 0);
+            datagramChannel.socket.setReuseAddress(reuseAddress);
             return this;
         } catch (IOException e) {
             throw new ChannelException(e);
@@ -284,7 +283,7 @@ public final class EpollDatagramChannelConfig extends EpollChannelConfig impleme
     @Override
     public boolean isBroadcast() {
         try {
-            return Native.isBroadcast(datagramChannel.fd().intValue()) == 1;
+            return datagramChannel.socket.isBroadcast();
         } catch (IOException e) {
             throw new ChannelException(e);
         }
@@ -293,7 +292,7 @@ public final class EpollDatagramChannelConfig extends EpollChannelConfig impleme
     @Override
     public EpollDatagramChannelConfig setBroadcast(boolean broadcast) {
         try {
-            Native.setBroadcast(datagramChannel.fd().intValue(), broadcast ? 1 : 0);
+            datagramChannel.socket.setBroadcast(broadcast);
             return this;
         } catch (IOException e) {
             throw new ChannelException(e);
@@ -351,7 +350,7 @@ public final class EpollDatagramChannelConfig extends EpollChannelConfig impleme
      */
     public boolean isReusePort() {
         try {
-            return Native.isReusePort(datagramChannel.fd().intValue()) == 1;
+            return datagramChannel.socket.isReusePort();
         } catch (IOException e) {
             throw new ChannelException(e);
         }
@@ -366,7 +365,7 @@ public final class EpollDatagramChannelConfig extends EpollChannelConfig impleme
      */
     public EpollDatagramChannelConfig setReusePort(boolean reusePort) {
         try {
-            Native.setReusePort(datagramChannel.fd().intValue(), reusePort ? 1 : 0);
+            datagramChannel.socket.setReusePort(reusePort);
             return this;
         } catch (IOException e) {
             throw new ChannelException(e);

transport-native-epoll/src/main/java/io/netty/channel/epoll/EpollDomainSocketChannel.java

@@ -23,12 +23,12 @@ import io.netty.channel.unix.DomainSocketAddress;
 import io.netty.channel.unix.DomainSocketChannel;
 import io.netty.channel.unix.FileDescriptor;
 import io.netty.channel.unix.PeerCredentials;
-import io.netty.channel.unix.Socket;
+import io.netty.util.internal.UnstableApi;
 
+import java.io.IOException;
 import java.net.SocketAddress;
 
-import static io.netty.channel.unix.Socket.newSocketDomain;
+import static io.netty.channel.epoll.LinuxSocket.newSocketDomain;
-import java.io.IOException;
 
 public final class EpollDomainSocketChannel extends AbstractEpollStreamChannel implements DomainSocketChannel {
     private final EpollDomainSocketChannelConfig config = new EpollDomainSocketChannelConfig(this);
@@ -40,33 +40,20 @@ public final class EpollDomainSocketChannel extends AbstractEpollStreamChannel i
         super(newSocketDomain(), false);
     }
 
-    /**
+    EpollDomainSocketChannel(Channel parent, FileDescriptor fd) {
-     * @deprecated Use {@link #EpollDomainSocketChannel(Channel, Socket)}.
+        super(parent, new LinuxSocket(fd.intValue()));
-     */
-    @Deprecated
-    public EpollDomainSocketChannel(Channel parent, FileDescriptor fd) {
-        super(parent, new Socket(fd.intValue()));
     }
 
-    /**
+    public EpollDomainSocketChannel(int fd) {
-     * @deprecated Use {@link #EpollDomainSocketChannel(Socket, boolean)}.
-     * <p>
-     * Creates a new {@link EpollDomainSocketChannel} from an existing {@link FileDescriptor}
-     */
-    @Deprecated
-    public EpollDomainSocketChannel(FileDescriptor fd) {
         super(fd);
     }
 
-    public EpollDomainSocketChannel(Channel parent, Socket fd) {
+    public EpollDomainSocketChannel(Channel parent, LinuxSocket fd) {
         super(parent, fd);
     }
 
-    /**
+    public EpollDomainSocketChannel(int fd, boolean active) {
-     * Creates a new {@link EpollDomainSocketChannel} from an existing {@link FileDescriptor}
+        super(new LinuxSocket(fd), active);
-     */
-    public EpollDomainSocketChannel(Socket fd, boolean active) {
-        super(fd, active);
     }
 
     @Override
@@ -86,7 +73,7 @@ public final class EpollDomainSocketChannel extends AbstractEpollStreamChannel i
 
     @Override
     protected void doBind(SocketAddress localAddress) throws Exception {
-        fd().bind(localAddress);
+        socket.bind(localAddress);
         local = (DomainSocketAddress) localAddress;
     }
 
@@ -118,7 +105,7 @@ public final class EpollDomainSocketChannel extends AbstractEpollStreamChannel i
     @Override
     protected boolean doWriteSingle(ChannelOutboundBuffer in, int writeSpinCount) throws Exception {
         Object msg = in.current();
-        if (msg instanceof FileDescriptor && Native.sendFd(fd().intValue(), ((FileDescriptor) msg).intValue()) > 0) {
+        if (msg instanceof FileDescriptor && socket.sendFd(((FileDescriptor) msg).intValue()) > 0) {
             // File descriptor was written, so remove it.
             in.remove();
             return true;
@@ -138,8 +125,9 @@ public final class EpollDomainSocketChannel extends AbstractEpollStreamChannel i
      * Returns the unix credentials (uid, gid, pid) of the peer
      * <a href=http://man7.org/linux/man-pages/man7/socket.7.html>SO_PEERCRED</a>
      */
+    @UnstableApi
     public PeerCredentials peerCredentials() throws IOException {
-        return fd().getPeerCredentials();
+        return socket.getPeerCredentials();
     }
 
     private final class EpollDomainUnsafe extends EpollStreamUnsafe {
@@ -158,7 +146,7 @@ public final class EpollDomainSocketChannel extends AbstractEpollStreamChannel i
         }
 
         private void epollInReadFd() {
-            if (fd().isInputShutdown()) {
+            if (socket.isInputShutdown()) {
                 clearEpollIn0();
                 return;
             }
@@ -175,7 +163,7 @@ public final class EpollDomainSocketChannel extends AbstractEpollStreamChannel i
                     // lastBytesRead represents the fd. We use lastBytesRead because it must be set so that the
                     // EpollRecvByteAllocatorHandle knows if it should try to read again or not when autoRead is
                     // enabled.
-                    allocHandle.lastBytesRead(Native.recvFd(fd().intValue()));
+                    allocHandle.lastBytesRead(socket.recvFd());
                     switch(allocHandle.lastBytesRead()) {
                     case 0:
                         break readLoop;

transport-native-epoll/src/main/java/io/netty/channel/epoll/EpollEventLoop.java

@@ -21,6 +21,7 @@ import io.netty.channel.SelectStrategy;
 import io.netty.channel.SingleThreadEventLoop;
 import io.netty.channel.epoll.AbstractEpollChannel.AbstractEpollUnsafe;
 import io.netty.channel.unix.FileDescriptor;
+import io.netty.channel.unix.IovArray;
 import io.netty.util.IntSupplier;
 import io.netty.util.collection.IntObjectHashMap;
 import io.netty.util.collection.IntObjectMap;
@@ -46,6 +47,12 @@ final class EpollEventLoop extends SingleThreadEventLoop {
     private static final AtomicIntegerFieldUpdater<EpollEventLoop> WAKEN_UP_UPDATER =
             AtomicIntegerFieldUpdater.newUpdater(EpollEventLoop.class, "wakenUp");
 
+    static {
+        // Ensure JNI is initialized by the time this class is loaded by this time!
+        // We use unix-common methods in this class which are backed by JNI methods.
+        Epoll.ensureAvailability();
+    }
+
     private final FileDescriptor epollFd;
     private final FileDescriptor eventFd;
     private final IntObjectMap<AbstractEpollChannel> channels = new IntObjectHashMap<AbstractEpollChannel>(4096);
@@ -132,7 +139,7 @@ final class EpollEventLoop extends SingleThreadEventLoop {
      */
     void add(AbstractEpollChannel ch) throws IOException {
         assert inEventLoop();
-        int fd = ch.fd().intValue();
+        int fd = ch.socket.intValue();
         Native.epollCtlAdd(epollFd.intValue(), fd, ch.flags);
         channels.put(fd, ch);
     }
@@ -142,7 +149,7 @@ final class EpollEventLoop extends SingleThreadEventLoop {
      */
     void modify(AbstractEpollChannel ch) throws IOException {
         assert inEventLoop();
-        Native.epollCtlMod(epollFd.intValue(), ch.fd().intValue(), ch.flags);
+        Native.epollCtlMod(epollFd.intValue(), ch.socket.intValue(), ch.flags);
     }
 
     /**
@@ -152,7 +159,7 @@ final class EpollEventLoop extends SingleThreadEventLoop {
         assert inEventLoop();
 
         if (ch.isOpen()) {
-            int fd = ch.fd().intValue();
+            int fd = ch.socket.intValue();
             if (channels.remove(fd) != null) {
                 // Remove the epoll. This is only needed if it's still open as otherwise it will be automatically
                 // removed once the file-descriptor is closed.

transport-native-epoll/src/main/java/io/netty/channel/epoll/EpollEventLoopGroup.java

@@ -33,6 +33,10 @@ import java.util.concurrent.ThreadFactory;
  * it only works on linux.
  */
 public final class EpollEventLoopGroup extends MultithreadEventLoopGroup {
+    static {
+        // Ensure JNI is initialized by the time this class is loaded by this time!
+        Epoll.ensureAvailability();
+    }
 
     /**
      * Create a new instance using the default number of threads and the default {@link ThreadFactory}.

transport-native-epoll/src/main/java/io/netty/channel/epoll/EpollRecvByteAllocatorHandle.java

@@ -24,14 +24,14 @@ import io.netty.util.internal.ObjectUtil;
 
 class EpollRecvByteAllocatorHandle implements RecvByteBufAllocator.ExtendedHandle {
     private final RecvByteBufAllocator.ExtendedHandle delegate;
-    private boolean isEdgeTriggered;
-    private boolean receivedRdHup;
     private final UncheckedBooleanSupplier defaultMaybeMoreDataSupplier = new UncheckedBooleanSupplier() {
         @Override
         public boolean get() {
             return maybeMoreDataToRead();
         }
     };
+    private boolean isEdgeTriggered;
+    private boolean receivedRdHup;
 
     EpollRecvByteAllocatorHandle(RecvByteBufAllocator.ExtendedHandle handle) {
         this.delegate = ObjectUtil.checkNotNull(handle, "handle");

transport-native-epoll/src/main/java/io/netty/channel/epoll/EpollServerChannelConfig.java

@@ -21,6 +21,7 @@ import io.netty.channel.ChannelOption;
 import io.netty.channel.MessageSizeEstimator;
 import io.netty.channel.RecvByteBufAllocator;
 import io.netty.channel.WriteBufferWaterMark;
+import io.netty.channel.socket.ServerSocketChannelConfig;
 import io.netty.util.NetUtil;
 
 import java.io.IOException;
@@ -30,7 +31,7 @@ import static io.netty.channel.ChannelOption.SO_BACKLOG;
 import static io.netty.channel.ChannelOption.SO_RCVBUF;
 import static io.netty.channel.ChannelOption.SO_REUSEADDR;
 
-public class EpollServerChannelConfig extends EpollChannelConfig {
+public class EpollServerChannelConfig extends EpollChannelConfig implements ServerSocketChannelConfig {
     protected final AbstractEpollChannel channel;
     private volatile int backlog = NetUtil.SOMAXCONN;
     private volatile int pendingFastOpenRequestsThreshold;
@@ -84,7 +85,7 @@ public class EpollServerChannelConfig extends EpollChannelConfig {
 
     public boolean isReuseAddress() {
         try {
-            return Native.isReuseAddress(channel.fd().intValue()) == 1;
+            return channel.socket.isReuseAddress();
         } catch (IOException e) {
             throw new ChannelException(e);
         }
@@ -92,7 +93,7 @@ public class EpollServerChannelConfig extends EpollChannelConfig {
 
     public EpollServerChannelConfig setReuseAddress(boolean reuseAddress) {
         try {
-            Native.setReuseAddress(channel.fd().intValue(), reuseAddress ? 1 : 0);
+            channel.socket.setReuseAddress(reuseAddress);
             return this;
         } catch (IOException e) {
             throw new ChannelException(e);
@@ -101,7 +102,7 @@ public class EpollServerChannelConfig extends EpollChannelConfig {
 
     public int getReceiveBufferSize() {
         try {
-            return channel.fd().getReceiveBufferSize();
+            return channel.socket.getReceiveBufferSize();
         } catch (IOException e) {
             throw new ChannelException(e);
         }
@@ -109,7 +110,7 @@ public class EpollServerChannelConfig extends EpollChannelConfig {
 
     public EpollServerChannelConfig setReceiveBufferSize(int receiveBufferSize) {
         try {
-            channel.fd().setReceiveBufferSize(receiveBufferSize);
+            channel.socket.setReceiveBufferSize(receiveBufferSize);
             return this;
         } catch (IOException e) {
             throw new ChannelException(e);
@@ -154,6 +155,11 @@ public class EpollServerChannelConfig extends EpollChannelConfig {
         return this;
     }
 
+    @Override
+    public EpollServerChannelConfig setPerformancePreferences(int connectionTime, int latency, int bandwidth) {
+        return this;
+    }
+
     @Override
     public EpollServerChannelConfig setConnectTimeoutMillis(int connectTimeoutMillis) {
         super.setConnectTimeoutMillis(connectTimeoutMillis);

transport-native-epoll/src/main/java/io/netty/channel/epoll/EpollServerDomainSocketChannel.java

@@ -17,7 +17,6 @@ package io.netty.channel.epoll;
 
 import io.netty.channel.Channel;
 import io.netty.channel.unix.DomainSocketAddress;
-import io.netty.channel.unix.FileDescriptor;
 import io.netty.channel.unix.ServerDomainSocketChannel;
 import io.netty.channel.unix.Socket;
 import io.netty.util.internal.logging.InternalLogger;
@@ -26,8 +25,7 @@ import io.netty.util.internal.logging.InternalLoggerFactory;
 import java.io.File;
 import java.net.SocketAddress;
 
-import static io.netty.channel.unix.Socket.newSocketDomain;
+import static io.netty.channel.epoll.LinuxSocket.newSocketDomain;
-
 
 public final class EpollServerDomainSocketChannel extends AbstractEpollServerChannel
         implements ServerDomainSocketChannel {
@@ -41,22 +39,15 @@ public final class EpollServerDomainSocketChannel extends AbstractEpollServerCha
         super(newSocketDomain(), false);
     }
 
-    /**
+    public EpollServerDomainSocketChannel(int fd) {
-     * @deprecated Use {@link #EpollServerDomainSocketChannel(Socket, boolean)}.
-     * Creates a new {@link EpollServerDomainSocketChannel} from an existing {@link FileDescriptor}.
-     */
-    public EpollServerDomainSocketChannel(FileDescriptor fd) {
         super(fd);
     }
 
-    /**
+    EpollServerDomainSocketChannel(LinuxSocket fd) {
-     * @deprecated Use {@link #EpollServerDomainSocketChannel(Socket, boolean)}.
-     */
-    public EpollServerDomainSocketChannel(Socket fd) {
         super(fd);
     }
 
-    public EpollServerDomainSocketChannel(Socket fd, boolean active) {
+    EpollServerDomainSocketChannel(LinuxSocket fd, boolean active) {
         super(fd, active);
     }
 
@@ -72,8 +63,8 @@ public final class EpollServerDomainSocketChannel extends AbstractEpollServerCha
 
     @Override
     protected void doBind(SocketAddress localAddress) throws Exception {
-        fd().bind(localAddress);
+        socket.bind(localAddress);
-        fd().listen(config.getBacklog());
+        socket.listen(config.getBacklog());
         local = (DomainSocketAddress) localAddress;
         active = true;
     }

transport-native-epoll/src/main/java/io/netty/channel/epoll/EpollServerSocketChannel.java

@@ -18,8 +18,6 @@ package io.netty.channel.epoll;
 import io.netty.channel.Channel;
 import io.netty.channel.EventLoop;
 import io.netty.channel.socket.ServerSocketChannel;
-import io.netty.channel.unix.FileDescriptor;
-import io.netty.channel.unix.Socket;
 
 import java.io.IOException;
 import java.net.InetAddress;
@@ -29,8 +27,8 @@ import java.util.Collection;
 import java.util.Collections;
 import java.util.Map;
 
+import static io.netty.channel.epoll.LinuxSocket.newSocketStream;
 import static io.netty.channel.unix.NativeInetAddress.address;
-import static io.netty.channel.unix.Socket.newSocketStream;
 
 /**
  * {@link ServerSocketChannel} implementation that uses linux EPOLL Edge-Triggered Mode for
@@ -47,23 +45,13 @@ public final class EpollServerSocketChannel extends AbstractEpollServerChannel i
         config = new EpollServerSocketChannelConfig(this);
     }
 
-    /**
+    public EpollServerSocketChannel(int fd) {
-     * @deprecated Use {@link #EpollServerSocketChannel(Socket, boolean)}.
-     * Creates a new {@link EpollServerSocketChannel} from an existing {@link FileDescriptor}.
-     */
-    @Deprecated
-    public EpollServerSocketChannel(FileDescriptor fd) {
         // Must call this constructor to ensure this object's local address is configured correctly.
         // The local address can only be obtained from a Socket object.
-        this(new Socket(fd.intValue()));
+        this(new LinuxSocket(fd));
     }
 
-    /**
+    EpollServerSocketChannel(LinuxSocket fd) {
-     * @deprecated Use {@link #EpollServerSocketChannel(Socket, boolean)}.
-     * Creates a new {@link EpollServerSocketChannel} from an existing {@link Socket}.
-     */
-    @Deprecated
-    public EpollServerSocketChannel(Socket fd) {
         super(fd);
         // As we create an EpollServerSocketChannel from a FileDescriptor we should try to obtain the remote and local
         // address from it. This is needed as the FileDescriptor may be bound already.
@@ -71,7 +59,7 @@ public final class EpollServerSocketChannel extends AbstractEpollServerChannel i
         config = new EpollServerSocketChannelConfig(this);
     }
 
-    public EpollServerSocketChannel(Socket fd, boolean active) {
+    EpollServerSocketChannel(LinuxSocket fd, boolean active) {
         super(fd, active);
         // As we create an EpollServerSocketChannel from a FileDescriptor we should try to obtain the remote and local
         // address from it. This is needed as the FileDescriptor may be bound already.
@@ -88,12 +76,12 @@ public final class EpollServerSocketChannel extends AbstractEpollServerChannel i
     protected void doBind(SocketAddress localAddress) throws Exception {
         InetSocketAddress addr = (InetSocketAddress) localAddress;
         checkResolvable(addr);
-        fd().bind(addr);
+        socket.bind(addr);
-        local = fd().localAddress();
+        local = socket.localAddress();
         if (Native.IS_SUPPORTING_TCP_FASTOPEN && config.getTcpFastopen() > 0) {
-            Native.setTcpFastopen(fd().intValue(), config.getTcpFastopen());
+            socket.setTcpFastOpen(config.getTcpFastopen());
         }
-        fd().listen(config.getBacklog());
+        socket.listen(config.getBacklog());
         active = true;
     }
 
@@ -119,7 +107,7 @@ public final class EpollServerSocketChannel extends AbstractEpollServerChannel i
 
     @Override
     protected Channel newChildChannel(int fd, byte[] address, int offset, int len) throws Exception {
-        return new EpollSocketChannel(this, new Socket(fd), address(address, offset, len));
+        return new EpollSocketChannel(this, new LinuxSocket(fd), address(address, offset, len));
     }
 
     Collection<InetAddress> tcpMd5SigAddresses() {

transport-native-epoll/src/main/java/io/netty/channel/epoll/EpollServerSocketChannelConfig.java

@@ -186,7 +186,7 @@ public final class EpollServerSocketChannelConfig extends EpollServerChannelConf
      */
     public boolean isReusePort() {
         try {
-            return Native.isReusePort(channel.fd().intValue()) == 1;
+            return channel.socket.isReusePort();
         } catch (IOException e) {
             throw new ChannelException(e);
         }
@@ -201,7 +201,7 @@ public final class EpollServerSocketChannelConfig extends EpollServerChannelConf
      */
     public EpollServerSocketChannelConfig setReusePort(boolean reusePort) {
         try {
-            Native.setReusePort(channel.fd().intValue(), reusePort ? 1 : 0);
+            channel.socket.setReusePort(reusePort);
             return this;
         } catch (IOException e) {
             throw new ChannelException(e);
@@ -214,7 +214,7 @@ public final class EpollServerSocketChannelConfig extends EpollServerChannelConf
      */
     public boolean isFreeBind() {
         try {
-            return Native.isIpFreeBind(channel.fd().intValue()) != 0;
+            return channel.socket.isIpFreeBind();
         } catch (IOException e) {
             throw new ChannelException(e);
         }
@@ -226,7 +226,7 @@ public final class EpollServerSocketChannelConfig extends EpollServerChannelConf
      */
     public EpollServerSocketChannelConfig setFreeBind(boolean freeBind) {
         try {
-            Native.setIpFreeBind(channel.fd().intValue(), freeBind ? 1 : 0);
+            channel.socket.setIpFreeBind(freeBind);
             return this;
         } catch (IOException e) {
             throw new ChannelException(e);
@@ -238,7 +238,7 @@ public final class EpollServerSocketChannelConfig extends EpollServerChannelConf
      */
     public EpollServerSocketChannelConfig setTcpDeferAccept(int deferAccept) {
         try {
-            channel.fd().setTcpDeferAccept(deferAccept);
+            channel.socket.setTcpDeferAccept(deferAccept);
             return this;
         } catch (IOException e) {
             throw new ChannelException(e);
@@ -250,7 +250,7 @@ public final class EpollServerSocketChannelConfig extends EpollServerChannelConf
      */
     public int getTcpDeferAccept() {
         try {
-            return channel.fd().getTcpDeferAccept();
+            return channel.socket.getTcpDeferAccept();
         } catch (IOException e) {
             throw new ChannelException(e);
         }

transport-native-epoll/src/main/java/io/netty/channel/epoll/EpollSocketChannel.java

@@ -19,8 +19,6 @@ import io.netty.channel.Channel;
 import io.netty.channel.ChannelException;
 import io.netty.channel.socket.ServerSocketChannel;
 import io.netty.channel.socket.SocketChannel;
-import io.netty.channel.unix.FileDescriptor;
-import io.netty.channel.unix.Socket;
 import io.netty.util.concurrent.GlobalEventExecutor;
 import io.netty.util.internal.PlatformDependent;
 
@@ -35,7 +33,7 @@ import java.util.Collections;
 import java.util.Map;
 import java.util.concurrent.Executor;
 
-import static io.netty.channel.unix.Socket.newSocketStream;
+import static io.netty.channel.epoll.LinuxSocket.newSocketStream;
 
 /**
  * {@link SocketChannel} implementation that uses linux EPOLL Edge-Triggered Mode for
@@ -51,7 +49,7 @@ public final class EpollSocketChannel extends AbstractEpollStreamChannel impleme
 
     private volatile Collection<InetAddress> tcpMd5SigAddresses = Collections.emptyList();
 
-    EpollSocketChannel(Channel parent, Socket fd, InetSocketAddress remote) {
+    EpollSocketChannel(Channel parent, LinuxSocket fd, InetSocketAddress remote) {
         super(parent, fd);
         config = new EpollSocketChannelConfig(this);
         // Directly cache the remote and local addresses
@@ -69,23 +67,16 @@ public final class EpollSocketChannel extends AbstractEpollStreamChannel impleme
         config = new EpollSocketChannelConfig(this);
     }
 
-    /**
+    public EpollSocketChannel(int fd) {
-     * @deprecated Use {@link #EpollSocketChannel(Socket, boolean)}.
-     */
-    @Deprecated
-    public EpollSocketChannel(FileDescriptor fd) {
         super(fd);
         // As we create an EpollSocketChannel from a FileDescriptor we should try to obtain the remote and local
         // address from it. This is needed as the FileDescriptor may be bound/connected already.
-        remote = fd().remoteAddress();
+        remote = socket.remoteAddress();
-        local = fd().localAddress();
+        local = socket.localAddress();
         config = new EpollSocketChannelConfig(this);
     }
 
-    /**
+    EpollSocketChannel(LinuxSocket fd, boolean active) {
-     * Creates a new {@link EpollSocketChannel} from an existing {@link FileDescriptor}.
-     */
-    public EpollSocketChannel(Socket fd, boolean active) {
         super(fd, active);
         // As we create an EpollSocketChannel from a FileDescriptor we should try to obtain the remote and local
         // address from it. This is needed as the FileDescriptor may be bound/connected already.
@@ -107,7 +98,7 @@ public final class EpollSocketChannel extends AbstractEpollStreamChannel impleme
      */
     public EpollTcpInfo tcpInfo(EpollTcpInfo info) {
         try {
-            Native.tcpInfo(fd().intValue(), info);
+            socket.getTcpInfo(info);
             return info;
         } catch (IOException e) {
             throw new ChannelException(e);
@@ -137,8 +128,8 @@ public final class EpollSocketChannel extends AbstractEpollStreamChannel impleme
     @Override
     protected void doBind(SocketAddress local) throws Exception {
         InetSocketAddress localAddress = (InetSocketAddress) local;
-        fd().bind(localAddress);
+        socket.bind(localAddress);
-        this.local = fd().localAddress();
+        this.local = socket.localAddress();
     }
 
     @Override
@@ -192,7 +183,7 @@ public final class EpollSocketChannel extends AbstractEpollStreamChannel impleme
 
         boolean connected = super.doConnect(remoteAddress, localAddress);
         if (connected) {
-            remote = computeRemoteAddr(remoteAddr, fd().remoteAddress());
+            remote = computeRemoteAddr(remoteAddr, socket.remoteAddress());
         } else {
             // Store for later usage in doFinishConnect()
             requestedRemote = remoteAddr;
@@ -200,7 +191,7 @@ public final class EpollSocketChannel extends AbstractEpollStreamChannel impleme
         // We always need to set the localAddress even if not connected yet as the bind already took place.
         //
         // See https://github.com/netty/netty/issues/3463
-        local = fd().localAddress();
+        local = socket.localAddress();
         return connected;
     }
 
@@ -229,7 +220,7 @@ public final class EpollSocketChannel extends AbstractEpollStreamChannel impleme
         @Override
         boolean doFinishConnect() throws Exception {
             if (super.doFinishConnect()) {
-                remote = computeRemoteAddr(requestedRemote, fd().remoteAddress());
+                remote = computeRemoteAddr(requestedRemote, socket.remoteAddress());
                 requestedRemote = null;
                 return true;
             }

transport-native-epoll/src/main/java/io/netty/channel/epoll/EpollSocketChannelConfig.java

@@ -28,10 +28,16 @@ import java.io.IOException;
 import java.net.InetAddress;
 import java.util.Map;
 
-import static io.netty.channel.ChannelOption.*;
+import static io.netty.channel.ChannelOption.ALLOW_HALF_CLOSURE;
+import static io.netty.channel.ChannelOption.IP_TOS;
+import static io.netty.channel.ChannelOption.SO_KEEPALIVE;
+import static io.netty.channel.ChannelOption.SO_LINGER;
+import static io.netty.channel.ChannelOption.SO_RCVBUF;
+import static io.netty.channel.ChannelOption.SO_REUSEADDR;
+import static io.netty.channel.ChannelOption.SO_SNDBUF;
+import static io.netty.channel.ChannelOption.TCP_NODELAY;
 
 public final class EpollSocketChannelConfig extends EpollChannelConfig implements SocketChannelConfig {
-    private static final long MAX_UINT32_T = 0xFFFFFFFFL;
     private final EpollSocketChannel channel;
     private volatile boolean allowHalfClosure;
 
@@ -156,7 +162,7 @@ public final class EpollSocketChannelConfig extends EpollChannelConfig implement
     @Override
     public int getReceiveBufferSize() {
         try {
-            return channel.fd().getReceiveBufferSize();
+            return channel.socket.getReceiveBufferSize();
         } catch (IOException e) {
             throw new ChannelException(e);
         }
@@ -165,7 +171,7 @@ public final class EpollSocketChannelConfig extends EpollChannelConfig implement
     @Override
     public int getSendBufferSize() {
         try {
-            return channel.fd().getSendBufferSize();
+            return channel.socket.getSendBufferSize();
         } catch (IOException e) {
             throw new ChannelException(e);
         }
@@ -174,7 +180,7 @@ public final class EpollSocketChannelConfig extends EpollChannelConfig implement
     @Override
     public int getSoLinger() {
         try {
-            return channel.fd().getSoLinger();
+            return channel.socket.getSoLinger();
         } catch (IOException e) {
             throw new ChannelException(e);
         }
@@ -183,7 +189,7 @@ public final class EpollSocketChannelConfig extends EpollChannelConfig implement
     @Override
     public int getTrafficClass() {
         try {
-            return Native.getTrafficClass(channel.fd().intValue());
+            return channel.socket.getTrafficClass();
         } catch (IOException e) {
             throw new ChannelException(e);
         }
@@ -192,7 +198,7 @@ public final class EpollSocketChannelConfig extends EpollChannelConfig implement
     @Override
     public boolean isKeepAlive() {
         try {
-            return channel.fd().isKeepAlive();
+            return channel.socket.isKeepAlive();
         } catch (IOException e) {
             throw new ChannelException(e);
         }
@@ -201,7 +207,7 @@ public final class EpollSocketChannelConfig extends EpollChannelConfig implement
     @Override
     public boolean isReuseAddress() {
         try {
-            return Native.isReuseAddress(channel.fd().intValue()) == 1;
+            return channel.socket.isReuseAddress();
         } catch (IOException e) {
             throw new ChannelException(e);
         }
@@ -210,7 +216,7 @@ public final class EpollSocketChannelConfig extends EpollChannelConfig implement
     @Override
     public boolean isTcpNoDelay() {
         try {
-            return channel.fd().isTcpNoDelay();
+            return channel.socket.isTcpNoDelay();
         } catch (IOException e) {
             throw new ChannelException(e);
         }
@@ -221,7 +227,7 @@ public final class EpollSocketChannelConfig extends EpollChannelConfig implement
      */
     public boolean isTcpCork() {
         try {
-            return channel.fd().isTcpCork();
+            return channel.socket.isTcpCork();
         } catch (IOException e) {
             throw new ChannelException(e);
         }
@@ -233,7 +239,7 @@ public final class EpollSocketChannelConfig extends EpollChannelConfig implement
      */
     public long getTcpNotSentLowAt() {
         try {
-            return Native.getTcpNotSentLowAt(channel.fd().intValue()) & MAX_UINT32_T;
+            return channel.socket.getTcpNotSentLowAt();
         } catch (IOException e) {
             throw new ChannelException(e);
         }
@@ -244,7 +250,7 @@ public final class EpollSocketChannelConfig extends EpollChannelConfig implement
      */
     public int getTcpKeepIdle() {
         try {
-            return Native.getTcpKeepIdle(channel.fd().intValue());
+            return channel.socket.getTcpKeepIdle();
         } catch (IOException e) {
             throw new ChannelException(e);
         }
@@ -255,7 +261,7 @@ public final class EpollSocketChannelConfig extends EpollChannelConfig implement
      */
     public int getTcpKeepIntvl() {
         try {
-            return Native.getTcpKeepIntvl(channel.fd().intValue());
+            return channel.socket.getTcpKeepIntvl();
         } catch (IOException e) {
             throw new ChannelException(e);
         }
@@ -266,7 +272,7 @@ public final class EpollSocketChannelConfig extends EpollChannelConfig implement
      */
     public int getTcpKeepCnt() {
         try {
-            return Native.getTcpKeepCnt(channel.fd().intValue());
+            return channel.socket.getTcpKeepCnt();
         } catch (IOException e) {
             throw new ChannelException(e);
         }
@@ -277,7 +283,7 @@ public final class EpollSocketChannelConfig extends EpollChannelConfig implement
      */
     public int getTcpUserTimeout() {
         try {
-        return Native.getTcpUserTimeout(channel.fd().intValue());
+            return channel.socket.getTcpUserTimeout();
         } catch (IOException e) {
             throw new ChannelException(e);
         }
@@ -286,7 +292,7 @@ public final class EpollSocketChannelConfig extends EpollChannelConfig implement
     @Override
     public EpollSocketChannelConfig setKeepAlive(boolean keepAlive) {
         try {
-            channel.fd().setKeepAlive(keepAlive);
+            channel.socket.setKeepAlive(keepAlive);
             return this;
         } catch (IOException e) {
             throw new ChannelException(e);
@@ -302,7 +308,7 @@ public final class EpollSocketChannelConfig extends EpollChannelConfig implement
     @Override
     public EpollSocketChannelConfig setReceiveBufferSize(int receiveBufferSize) {
         try {
-            channel.fd().setReceiveBufferSize(receiveBufferSize);
+            channel.socket.setReceiveBufferSize(receiveBufferSize);
             return this;
         } catch (IOException e) {
             throw new ChannelException(e);
@@ -312,7 +318,7 @@ public final class EpollSocketChannelConfig extends EpollChannelConfig implement
     @Override
     public EpollSocketChannelConfig setReuseAddress(boolean reuseAddress) {
         try {
-            Native.setReuseAddress(channel.fd().intValue(), reuseAddress ? 1 : 0);
+            channel.socket.setReuseAddress(reuseAddress);
             return this;
         } catch (IOException e) {
             throw new ChannelException(e);
@@ -322,7 +328,7 @@ public final class EpollSocketChannelConfig extends EpollChannelConfig implement
     @Override
     public EpollSocketChannelConfig setSendBufferSize(int sendBufferSize) {
         try {
-            channel.fd().setSendBufferSize(sendBufferSize);
+            channel.socket.setSendBufferSize(sendBufferSize);
             return this;
         } catch (IOException e) {
             throw new ChannelException(e);
@@ -332,7 +338,7 @@ public final class EpollSocketChannelConfig extends EpollChannelConfig implement
     @Override
     public EpollSocketChannelConfig setSoLinger(int soLinger) {
         try {
-            channel.fd().setSoLinger(soLinger);
+            channel.socket.setSoLinger(soLinger);
             return this;
         } catch (IOException e) {
             throw new ChannelException(e);
@@ -342,7 +348,7 @@ public final class EpollSocketChannelConfig extends EpollChannelConfig implement
     @Override
     public EpollSocketChannelConfig setTcpNoDelay(boolean tcpNoDelay) {
         try {
-            channel.fd().setTcpNoDelay(tcpNoDelay);
+            channel.socket.setTcpNoDelay(tcpNoDelay);
             return this;
         } catch (IOException e) {
             throw new ChannelException(e);
@@ -354,7 +360,7 @@ public final class EpollSocketChannelConfig extends EpollChannelConfig implement
      */
     public EpollSocketChannelConfig setTcpCork(boolean tcpCork) {
         try {
-            channel.fd().setTcpCork(tcpCork);
+            channel.socket.setTcpCork(tcpCork);
             return this;
         } catch (IOException e) {
             throw new ChannelException(e);
@@ -366,11 +372,8 @@ public final class EpollSocketChannelConfig extends EpollChannelConfig implement
      * @param tcpNotSentLowAt is a uint32_t
      */
     public EpollSocketChannelConfig setTcpNotSentLowAt(long tcpNotSentLowAt) {
-        if (tcpNotSentLowAt < 0 || tcpNotSentLowAt > MAX_UINT32_T) {
-            throw new IllegalArgumentException("tcpNotSentLowAt must be a uint32_t");
-        }
         try {
-            Native.setTcpNotSentLowAt(channel.fd().intValue(), (int) tcpNotSentLowAt);
+            channel.socket.setTcpNotSentLowAt(tcpNotSentLowAt);
             return this;
         } catch (IOException e) {
             throw new ChannelException(e);
@@ -380,7 +383,7 @@ public final class EpollSocketChannelConfig extends EpollChannelConfig implement
     @Override
     public EpollSocketChannelConfig setTrafficClass(int trafficClass) {
         try {
-            Native.setTrafficClass(channel.fd().intValue(), trafficClass);
+            channel.socket.setTrafficClass(trafficClass);
             return this;
         } catch (IOException e) {
             throw new ChannelException(e);
@@ -392,7 +395,7 @@ public final class EpollSocketChannelConfig extends EpollChannelConfig implement
      */
     public EpollSocketChannelConfig setTcpKeepIdle(int seconds) {
         try {
-            Native.setTcpKeepIdle(channel.fd().intValue(), seconds);
+            channel.socket.setTcpKeepIdle(seconds);
             return this;
         } catch (IOException e) {
             throw new ChannelException(e);
@@ -404,7 +407,7 @@ public final class EpollSocketChannelConfig extends EpollChannelConfig implement
      */
     public EpollSocketChannelConfig setTcpKeepIntvl(int seconds) {
         try {
-            Native.setTcpKeepIntvl(channel.fd().intValue(), seconds);
+            channel.socket.setTcpKeepIntvl(seconds);
             return this;
         } catch (IOException e) {
             throw new ChannelException(e);
@@ -416,7 +419,7 @@ public final class EpollSocketChannelConfig extends EpollChannelConfig implement
      */
     public EpollSocketChannelConfig setTcpKeepCntl(int probes) {
         try {
-            Native.setTcpKeepCnt(channel.fd().intValue(), probes);
+            channel.socket.setTcpKeepCnt(probes);
             return this;
         } catch (IOException e) {
             throw new ChannelException(e);
@@ -428,7 +431,7 @@ public final class EpollSocketChannelConfig extends EpollChannelConfig implement
      */
     public EpollSocketChannelConfig setTcpUserTimeout(int milliseconds) {
         try {
-            Native.setTcpUserTimeout(channel.fd().intValue(), milliseconds);
+            channel.socket.setTcpUserTimeout(milliseconds);
             return this;
         } catch (IOException e) {
             throw new ChannelException(e);
@@ -455,7 +458,7 @@ public final class EpollSocketChannelConfig extends EpollChannelConfig implement
      */
     public EpollSocketChannelConfig setTcpQuickAck(boolean quickAck) {
         try {
-            channel.fd().setTcpQuickAck(quickAck);
+            channel.socket.setTcpQuickAck(quickAck);
             return this;
         } catch (IOException e) {
             throw new ChannelException(e);
@@ -468,7 +471,7 @@ public final class EpollSocketChannelConfig extends EpollChannelConfig implement
      */
     public boolean isTcpQuickAck() {
         try {
-            return channel.fd().isTcpQuickAck();
+            return channel.socket.isTcpQuickAck();
         } catch (IOException e) {
             throw new ChannelException(e);
         }

transport-native-epoll/src/main/java/io/netty/channel/epoll/LinuxSocket.java

@@ -0,0 +1,162 @@
+/*
+ * Copyright 2016 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache License,
+ * version 2.0 (the "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at:
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+package io.netty.channel.epoll;
+
+import io.netty.channel.unix.NativeInetAddress;
+import io.netty.channel.unix.PeerCredentials;
+import io.netty.channel.unix.Socket;
+
+import java.io.IOException;
+import java.net.InetAddress;
+
+/**
+ * A socket which provides access Linux native methods.
+ */
+final class LinuxSocket extends Socket {
+    private static final long MAX_UINT32_T = 0xFFFFFFFFL;
+
+    public LinuxSocket(int fd) {
+        super(fd);
+    }
+
+    void setTcpDeferAccept(int deferAccept) throws IOException {
+        setTcpDeferAccept(intValue(), deferAccept);
+    }
+
+    void setTcpQuickAck(boolean quickAck) throws IOException {
+        setTcpQuickAck(intValue(), quickAck ? 1 : 0);
+    }
+
+    void setTcpCork(boolean tcpCork) throws IOException {
+        setTcpCork(intValue(), tcpCork ? 1 : 0);
+    }
+
+    void setTcpNotSentLowAt(long tcpNotSentLowAt) throws IOException {
+        if (tcpNotSentLowAt < 0 || tcpNotSentLowAt > MAX_UINT32_T) {
+            throw new IllegalArgumentException("tcpNotSentLowAt must be a uint32_t");
+        }
+        setTcpNotSentLowAt(intValue(), (int) tcpNotSentLowAt);
+    }
+
+    void setTcpFastOpen(int tcpFastopenBacklog) throws IOException {
+        setTcpFastOpen(intValue(), tcpFastopenBacklog);
+    }
+
+    void setTcpKeepIdle(int seconds) throws IOException {
+        setTcpKeepIdle(intValue(), seconds);
+    }
+
+    void setTcpKeepIntvl(int seconds) throws IOException {
+        setTcpKeepIntvl(intValue(), seconds);
+    }
+
+    void setTcpKeepCnt(int probes) throws IOException {
+        setTcpKeepCnt(intValue(), probes);
+    }
+
+    void setTcpUserTimeout(int milliseconds) throws IOException {
+        setTcpUserTimeout(intValue(), milliseconds);
+    }
+
+    void setIpFreeBind(boolean enabled) throws IOException {
+        setIpFreeBind(intValue(), enabled ? 1 : 0);
+    }
+
+    void getTcpInfo(EpollTcpInfo info) throws IOException {
+        getTcpInfo(intValue(), info.info);
+    }
+
+    void setTcpMd5Sig(InetAddress address, byte[] key) throws IOException {
+        final NativeInetAddress a = NativeInetAddress.newInstance(address);
+        setTcpMd5Sig(intValue(), a.address(), a.scopeId(), key);
+    }
+
+    boolean isTcpCork() throws IOException  {
+        return isTcpCork(intValue()) != 0;
+    }
+
+    int getTcpDeferAccept() throws IOException {
+        return getTcpDeferAccept(intValue());
+    }
+
+    boolean isTcpQuickAck() throws IOException {
+        return isTcpQuickAck(intValue()) != 0;
+    }
+
+    long getTcpNotSentLowAt() throws IOException {
+        return getTcpNotSentLowAt(intValue()) & MAX_UINT32_T;
+    }
+
+    int getTcpKeepIdle() throws IOException {
+        return getTcpKeepIdle(intValue());
+    }
+
+    int getTcpKeepIntvl() throws IOException {
+        return getTcpKeepIntvl(intValue());
+    }
+
+    int getTcpKeepCnt() throws IOException {
+        return getTcpKeepCnt(intValue());
+    }
+
+    int getTcpUserTimeout() throws IOException {
+        return getTcpUserTimeout(intValue());
+    }
+
+    boolean isIpFreeBind() throws IOException {
+        return isIpFreeBind(intValue()) != 0;
+    }
+
+    PeerCredentials getPeerCredentials() throws IOException {
+        return getPeerCredentials(intValue());
+    }
+
+    public static LinuxSocket newSocketStream() {
+        return new LinuxSocket(newSocketStream0());
+    }
+
+    public static LinuxSocket newSocketDgram() {
+        return new LinuxSocket(newSocketDgram0());
+    }
+
+    public static LinuxSocket newSocketDomain() {
+        return new LinuxSocket(newSocketDomain0());
+    }
+
+    private static native int getTcpDeferAccept(int fd) throws IOException;
+    private static native int isTcpQuickAck(int fd) throws IOException;
+    private static native int isTcpCork(int fd) throws IOException;
+    private static native int getTcpNotSentLowAt(int fd) throws IOException;
+    private static native int getTcpKeepIdle(int fd) throws IOException;
+    private static native int getTcpKeepIntvl(int fd) throws IOException;
+    private static native int getTcpKeepCnt(int fd) throws IOException;
+    private static native int getTcpUserTimeout(int fd) throws IOException;
+    private static native int isIpFreeBind(int fd) throws IOException;
+    private static native void getTcpInfo(int fd, int[] array) throws IOException;
+    private static native PeerCredentials getPeerCredentials(int fd) throws IOException;
+
+    private static native void setTcpDeferAccept(int fd, int deferAccept) throws IOException;
+    private static native void setTcpQuickAck(int fd, int quickAck) throws IOException;
+    private static native void setTcpCork(int fd, int tcpCork) throws IOException;
+    private static native void setTcpNotSentLowAt(int fd, int tcpNotSentLowAt) throws IOException;
+    private static native void setTcpFastOpen(int fd, int tcpFastopenBacklog) throws IOException;
+    private static native void setTcpKeepIdle(int fd, int seconds) throws IOException;
+    private static native void setTcpKeepIntvl(int fd, int seconds) throws IOException;
+    private static native void setTcpKeepCnt(int fd, int probes) throws IOException;
+    private static native void setTcpUserTimeout(int fd, int milliseconds)throws IOException;
+    private static native void setIpFreeBind(int fd, int freeBind) throws IOException;
+    private static native void setTcpMd5Sig(int fd, byte[] address, int scopeId, byte[] key) throws IOException;
+}

transport-native-epoll/src/main/java/io/netty/channel/epoll/Native.java

@@ -34,13 +34,10 @@ import static io.netty.channel.epoll.NativeStaticallyReferencedJniMethods.epolle
 import static io.netty.channel.epoll.NativeStaticallyReferencedJniMethods.epollin;
 import static io.netty.channel.epoll.NativeStaticallyReferencedJniMethods.epollout;
 import static io.netty.channel.epoll.NativeStaticallyReferencedJniMethods.epollrdhup;
-import static io.netty.channel.epoll.NativeStaticallyReferencedJniMethods.iovMax;
 import static io.netty.channel.epoll.NativeStaticallyReferencedJniMethods.isSupportingSendmmsg;
 import static io.netty.channel.epoll.NativeStaticallyReferencedJniMethods.isSupportingTcpFastopen;
 import static io.netty.channel.epoll.NativeStaticallyReferencedJniMethods.kernelVersion;
-import static io.netty.channel.epoll.NativeStaticallyReferencedJniMethods.ssizeMax;
 import static io.netty.channel.epoll.NativeStaticallyReferencedJniMethods.tcpMd5SigMaxKeyLen;
-import static io.netty.channel.epoll.NativeStaticallyReferencedJniMethods.uioMaxIov;
 import static io.netty.channel.unix.Errors.ERRNO_EAGAIN_NEGATIVE;
 import static io.netty.channel.unix.Errors.ERRNO_EPIPE_NEGATIVE;
 import static io.netty.channel.unix.Errors.ERRNO_EWOULDBLOCK_NEGATIVE;
@@ -72,11 +69,8 @@ public final class Native {
     public static final int EPOLLET = epollet();
     public static final int EPOLLERR = epollerr();
 
-    public static final int IOV_MAX = iovMax();
-    public static final int UIO_MAX_IOV = uioMaxIov();
     public static final boolean IS_SUPPORTING_SENDMMSG = isSupportingSendmmsg();
     public static final boolean IS_SUPPORTING_TCP_FASTOPEN = isSupportingTcpFastopen();
-    public static final long SSIZE_MAX = ssizeMax();
     public static final int TCP_MD5SIG_MAXKEYLEN = tcpMd5SigMaxKeyLen();
     public static final String KERNEL_VERSION = kernelVersion();
 
@@ -185,82 +179,10 @@ public final class Native {
     private static native int sendmmsg0(
             int fd, NativeDatagramPacketArray.NativeDatagramPacket[] msgs, int offset, int len);
 
-    public static int recvFd(int fd) throws IOException {
-        int res = recvFd0(fd);
-        if (res > 0) {
-            return res;
-        }
-        if (res == 0) {
-            return -1;
-        }
-
-        if (res == ERRNO_EAGAIN_NEGATIVE || res == ERRNO_EWOULDBLOCK_NEGATIVE) {
-            // Everything consumed so just return -1 here.
-            return 0;
-        }
-        throw newIOException("recvFd", res);
-    }
-
-    private static native int recvFd0(int fd);
-
-    public static int sendFd(int socketFd, int fd) throws IOException {
-        int res = sendFd0(socketFd, fd);
-        if (res >= 0) {
-            return res;
-        }
-        if (res == ERRNO_EAGAIN_NEGATIVE || res == ERRNO_EWOULDBLOCK_NEGATIVE) {
-            // Everything consumed so just return -1 here.
-            return -1;
-        }
-        throw newIOException("sendFd", res);
-    }
-
-    private static native int sendFd0(int socketFd, int fd);
-
-    // Socket option operations
-    public static native int isReuseAddress(int fd) throws IOException;
-    public static native int isReusePort(int fd) throws IOException;
-    public static native int getTcpNotSentLowAt(int fd) throws IOException;
-    public static native int getTrafficClass(int fd) throws IOException;
-    public static native int isBroadcast(int fd) throws IOException;
-    public static native int getTcpKeepIdle(int fd) throws IOException;
-    public static native int getTcpKeepIntvl(int fd) throws IOException;
-    public static native int getTcpKeepCnt(int fd) throws IOException;
-    public static native int getTcpUserTimeout(int milliseconds) throws IOException;
-    public static native int isIpFreeBind(int fd)throws IOException;
-
-    public static native void setReuseAddress(int fd, int reuseAddress) throws IOException;
-    public static native void setReusePort(int fd, int reuseAddress) throws IOException;
-    public static native void setTcpFastopen(int fd, int tcpFastopenBacklog) throws IOException;
-    public static native void setTcpNotSentLowAt(int fd, int tcpNotSentLowAt) throws IOException;
-    public static native void setTrafficClass(int fd, int tcpNoDelay) throws IOException;
-    public static native void setBroadcast(int fd, int broadcast) throws IOException;
-    public static native void setTcpKeepIdle(int fd, int seconds) throws IOException;
-    public static native void setTcpKeepIntvl(int fd, int seconds) throws IOException;
-    public static native void setTcpKeepCnt(int fd, int probes) throws IOException;
-    public static native void setTcpUserTimeout(int fd, int milliseconds)throws IOException;
-    public static native void setIpFreeBind(int fd, int freeBind) throws IOException;
-    public static void tcpInfo(int fd, EpollTcpInfo info) throws IOException {
-        tcpInfo0(fd, info.info);
-    }
-
-    private static native void tcpInfo0(int fd, int[] array) throws IOException;
-
-    public static void setTcpMd5Sig(int fd, InetAddress address, byte[] key) throws IOException {
-        final NativeInetAddress a = NativeInetAddress.newInstance(address);
-        setTcpMd5Sig0(fd, a.address(), a.scopeId(), key);
-    }
-
-    private static native void setTcpMd5Sig0(int fd, byte[] address, int scopeId, byte[] key) throws IOException;
-
     // epoll_event related
     public static native int sizeofEpollEvent();
     public static native int offsetofEpollData();
 
-    private Native() {
-        // utility
-    }
-
     private static void loadNativeLibrary() {
         String name = SystemPropertyUtil.get("os.name").toLowerCase(Locale.UK).trim();
         if (!name.startsWith("linux")) {
@@ -269,4 +191,8 @@ public final class Native {
         NativeLibraryLoader.load(SystemPropertyUtil.get("io.netty.packagePrefix", "").replace('.', '-') +
             "netty-transport-native-epoll", PlatformDependent.getClassLoader(Native.class));
     }
+
+    private Native() {
+        // utility
+    }
 }

transport-native-epoll/src/main/java/io/netty/channel/epoll/NativeDatagramPacketArray.java

@@ -15,16 +15,18 @@
  */
 package io.netty.channel.epoll;
 
-import static io.netty.channel.unix.NativeInetAddress.ipv4MappedIpv6Address;
 import io.netty.buffer.ByteBuf;
 import io.netty.channel.ChannelOutboundBuffer;
 import io.netty.channel.socket.DatagramPacket;
+import io.netty.channel.unix.IovArray;
 import io.netty.util.concurrent.FastThreadLocal;
-
 import java.net.Inet6Address;
 import java.net.InetAddress;
 import java.net.InetSocketAddress;
 
+import static io.netty.channel.unix.Limits.UIO_MAX_IOV;
+import static io.netty.channel.unix.NativeInetAddress.ipv4MappedIpv6Address;
+
 /**
  * Support <a href="http://linux.die.net/man/2/sendmmsg">sendmmsg(...)</a> on linux with GLIBC 2.14+
  */
@@ -48,7 +50,7 @@ final class NativeDatagramPacketArray implements ChannelOutboundBuffer.MessagePr
             };
 
     // Use UIO_MAX_IOV as this is the maximum number we can write with one sendmmsg(...) call.
-    private final NativeDatagramPacket[] packets = new NativeDatagramPacket[Native.UIO_MAX_IOV];
+    private final NativeDatagramPacket[] packets = new NativeDatagramPacket[UIO_MAX_IOV];
     private int count;
 
     private NativeDatagramPacketArray() {

transport-native-epoll/src/main/java/io/netty/channel/epoll/TcpMd5Util.java

@@ -55,7 +55,7 @@ final class TcpMd5Util {
         // Remove mappings not present in the new set.
         for (InetAddress addr : current) {
             if (!newKeys.containsKey(addr)) {
-                Native.setTcpMd5Sig(channel.fd().intValue(), addr, null);
+                channel.socket.setTcpMd5Sig(addr, null);
             }
         }
 
@@ -66,7 +66,7 @@ final class TcpMd5Util {
         // Set new mappings and store addresses which we set.
         final Collection<InetAddress> addresses = new ArrayList<InetAddress>(newKeys.size());
         for (Entry<InetAddress, byte[]> e : newKeys.entrySet()) {
-            Native.setTcpMd5Sig(channel.fd().intValue(), e.getKey(), e.getValue());
+            channel.socket.setTcpMd5Sig(e.getKey(), e.getValue());
             addresses.add(e.getKey());
         }
 

transport-native-epoll/src/test/java/io/netty/channel/epoll/EpollAbstractDomainSocketEchoTest.java

@@ -23,6 +23,6 @@ public class EpollAbstractDomainSocketEchoTest extends EpollDomainSocketEchoTest
     @Override
     protected SocketAddress newSocketAddress() {
         // these don't actually show up in the file system so creating a temp file isn't reliable
-        return new DomainSocketAddress("\0/tmp/" + UUID.randomUUID());
+        return new DomainSocketAddress("\0" + System.getProperty("java.io.tmpdir") + UUID.randomUUID());
     }
 }

transport-native-epoll/src/test/java/io/netty/channel/epoll/EpollSocketChannelConfigTest.java

@@ -26,7 +26,9 @@ import java.net.InetSocketAddress;
 import java.nio.channels.ClosedChannelException;
 import java.util.Random;
 
+import org.junit.After;
 import org.junit.AfterClass;
+import org.junit.Before;
 import org.junit.BeforeClass;
 import org.junit.Test;
 
@@ -37,9 +39,18 @@ public class EpollSocketChannelConfigTest {
     private static Random rand;
 
     @BeforeClass
-    public static void before() {
+    public static void beforeClass() {
         rand = new Random();
         group = new EpollEventLoopGroup(1);
+    }
+
+    @AfterClass
+    public static void afterClass() {
+        group.shutdownGracefully();
+    }
+
+    @Before
+    public void setup() {
         Bootstrap bootstrap = new Bootstrap();
         ch = (EpollSocketChannel) bootstrap.group(group)
                 .channel(EpollSocketChannel.class)
@@ -47,13 +58,9 @@ public class EpollSocketChannelConfigTest {
                 .bind(new InetSocketAddress(0)).syncUninterruptibly().channel();
     }
 
-    @AfterClass
+    @After
-    public static void after() {
+    public void teardown() {
-        try {
+        ch.close().syncUninterruptibly();
-            ch.close().syncUninterruptibly();
-        } finally {
-            group.shutdownGracefully();
-        }
     }
 
     private long randLong(long min, long max) {

transport-native-epoll/src/test/java/io/netty/channel/epoll/EpollSocketTest.java

@@ -0,0 +1,63 @@
+/*
+ * Copyright 2016 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache License,
+ * version 2.0 (the "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at:
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+package io.netty.channel.epoll;
+
+import io.netty.channel.unix.DomainSocketAddress;
+import io.netty.channel.unix.PeerCredentials;
+import io.netty.channel.unix.tests.SocketTest;
+import io.netty.channel.unix.tests.UnixTestUtils;
+import org.junit.Test;
+
+import java.io.IOException;
+
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertNotEquals;
+import static org.junit.Assert.assertTrue;
+
+public class EpollSocketTest extends SocketTest<LinuxSocket> {
+    @Test
+    public void testTcpCork() throws Exception {
+        assertFalse(socket.isTcpCork());
+        socket.setTcpCork(true);
+        assertTrue(socket.isTcpCork());
+    }
+
+    @Test
+    public void testPeerCreds() throws IOException {
+        LinuxSocket s1 = LinuxSocket.newSocketDomain();
+        LinuxSocket s2 = LinuxSocket.newSocketDomain();
+
+        try {
+            DomainSocketAddress dsa = UnixTestUtils.newSocketAddress();
+            s1.bind(dsa);
+            s1.listen(1);
+
+            assertTrue(s2.connect(dsa));
+            byte [] addr = new byte[64];
+            s1.accept(addr);
+            PeerCredentials pc = s1.getPeerCredentials();
+            assertNotEquals(pc.uid(), -1);
+        } finally {
+            s1.close();
+            s2.close();
+        }
+    }
+
+    @Override
+    protected LinuxSocket newSocket() {
+        return LinuxSocket.newSocketStream();
+    }
+}

transport-native-epoll/src/test/java/io/netty/channel/epoll/EpollSocketTestPermutation.java

@@ -25,6 +25,7 @@ import io.netty.channel.socket.nio.NioDatagramChannel;
 import io.netty.channel.socket.nio.NioServerSocketChannel;
 import io.netty.channel.socket.nio.NioSocketChannel;
 import io.netty.channel.unix.DomainSocketAddress;
+import io.netty.channel.unix.tests.UnixTestUtils;
 import io.netty.testsuite.transport.TestsuitePermutation;
 import io.netty.testsuite.transport.TestsuitePermutation.BootstrapFactory;
 import io.netty.testsuite.transport.socket.SocketTestPermutation;
@@ -214,12 +215,6 @@ class EpollSocketTestPermutation extends SocketTestPermutation {
     }
 
     public static DomainSocketAddress newSocketAddress() {
-        try {
+        return UnixTestUtils.newSocketAddress();
-            File file = File.createTempFile("netty", "dsocket");
-            file.delete();
-            return new DomainSocketAddress(file);
-        } catch (IOException e) {
-            throw new IllegalStateException(e);
-        }
     }
 }

transport-native-kqueue/pom.xml

@@ -0,0 +1,197 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!--
+  ~ Copyright 2016 The Netty Project
+  ~
+  ~ The Netty Project licenses this file to you under the Apache License,
+  ~ version 2.0 (the "License"); you may not use this file except in compliance
+  ~ with the License. You may obtain a copy of the License at:
+  ~
+  ~   http://www.apache.org/licenses/LICENSE-2.0
+  ~
+  ~ Unless required by applicable law or agreed to in writing, software
+  ~ distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+  ~ WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+  ~ License for the specific language governing permissions and limitations
+  ~ under the License.
+  -->
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
+  <modelVersion>4.0.0</modelVersion>
+  <parent>
+    <groupId>io.netty</groupId>
+    <artifactId>netty-parent</artifactId>
+    <version>4.1.11.Final-SNAPSHOT</version>
+  </parent>
+  <artifactId>netty-transport-native-kqueue</artifactId>
+
+  <name>Netty/Transport/Native/KQueue</name>
+  <packaging>jar</packaging>
+
+  <profiles>
+    <profile>
+      <id>osx</id>
+      <activation>
+        <os>
+          <family>mac</family>
+        </os>
+      </activation>
+      <properties>
+        <jni.compiler.args.ldflags>LDFLAGS=-Wl,-weak_library,${unix.common.lib.unpacked.dir}/lib${unix.common.lib.name}.a</jni.compiler.args.ldflags>
+      </properties>
+    </profile>
+  </profiles>
+
+  <properties>
+    <!-- Needed by the native transport as we need the memoryAddress of the ByteBuffer -->
+    <argLine.java9.extras>--add-exports java.base/sun.security.x509=ALL-UNNAMED --add-opens=java.base/java.nio=ALL-UNNAMED</argLine.java9.extras>
+    <unix.common.lib.name>netty-unix-common</unix.common.lib.name>
+    <unix.common.lib.dir>${project.build.directory}/unix-common-lib</unix.common.lib.dir>
+    <unix.common.lib.unpacked.dir>${unix.common.lib.dir}/META-INF/native/lib</unix.common.lib.unpacked.dir>
+    <unix.common.include.unpacked.dir>${unix.common.lib.dir}/META-INF/native/include</unix.common.include.unpacked.dir>
+    <jni.compiler.args.cflags>CFLAGS=-O3 -Werror -fno-omit-frame-pointer -Wunused-variable -I${unix.common.include.unpacked.dir}</jni.compiler.args.cflags>
+    <jni.compiler.args.ldflags>LDFLAGS=-L${unix.common.lib.unpacked.dir} -Wl,--whole-archive -l${unix.common.lib.name} -Wl,--no-whole-archive</jni.compiler.args.ldflags>
+  </properties>
+
+  <dependencies>
+    <dependency>
+      <groupId>io.netty</groupId>
+      <artifactId>netty-common</artifactId>
+      <version>${project.version}</version>
+    </dependency>
+    <dependency>
+      <groupId>io.netty</groupId>
+      <artifactId>netty-buffer</artifactId>
+      <version>${project.version}</version>
+    </dependency>
+    <dependency>
+      <groupId>io.netty</groupId>
+      <artifactId>netty-transport-native-unix-common</artifactId>
+      <version>${project.version}</version>
+      <classifier>${jni.classifier}</classifier>
+      <!--
+      The unix-common with classifier dependency is optional because it is not a runtime dependency, but a build time
+      dependency to get the static library which is built directly into the shared library generated by this project.
+      -->
+      <optional>true</optional>
+    </dependency>
+    <dependency>
+      <groupId>io.netty</groupId>
+      <artifactId>netty-transport-native-unix-common</artifactId>
+      <version>${project.version}</version>
+    </dependency>
+    <dependency>
+      <groupId>io.netty</groupId>
+      <artifactId>netty-transport</artifactId>
+      <version>${project.version}</version>
+    </dependency>
+    <dependency>
+      <groupId>io.netty</groupId>
+      <artifactId>netty-testsuite</artifactId>
+      <version>${project.version}</version>
+      <scope>test</scope>
+    </dependency>
+    <dependency>
+      <groupId>io.netty</groupId>
+      <artifactId>netty-transport-native-unix-common-tests</artifactId>
+      <version>${project.version}</version>
+      <scope>test</scope>
+    </dependency>
+    <dependency>
+      <groupId>${project.groupId}</groupId>
+      <artifactId>${tcnative.artifactId}</artifactId>
+      <classifier>${tcnative.classifier}</classifier>
+      <scope>test</scope>
+    </dependency>
+  </dependencies>
+
+  <build>
+    <plugins>
+      <plugin>
+        <artifactId>maven-dependency-plugin</artifactId>
+        <executions>
+          <!-- unpack the unix-common static library and include files -->
+          <execution>
+            <id>unpack</id>
+            <phase>generate-sources</phase>
+            <goals>
+              <goal>unpack-dependencies</goal>
+            </goals>
+            <configuration>
+              <includeGroupIds>${project.groupId}</includeGroupIds>
+              <includeArtifactIds>netty-transport-native-unix-common</includeArtifactIds>
+              <classifier>${jni.classifier}</classifier>
+              <outputDirectory>${unix.common.lib.dir}</outputDirectory>
+              <includes>META-INF/native/**</includes>
+              <overWriteReleases>false</overWriteReleases>
+              <overWriteSnapshots>true</overWriteSnapshots>
+            </configuration>
+          </execution>
+        </executions>
+      </plugin>
+
+      <plugin>
+        <groupId>org.fusesource.hawtjni</groupId>
+        <artifactId>maven-hawtjni-plugin</artifactId>
+        <executions>
+          <execution>
+            <id>build-native-lib</id>
+            <configuration>
+              <nativeSourceDirectory>${project.basedir}/src/main/c</nativeSourceDirectory>
+              <libDirectory>${project.build.outputDirectory}</libDirectory>
+              <!-- We use Maven's artifact classifier instead.
+                   This hack will make the hawtjni plugin to put the native library
+                   under 'META-INF/native' rather than 'META-INF/native/${platform}'. -->
+              <platform>.</platform>
+              <forceConfigure>true</forceConfigure>
+              <forceAutogen>true</forceAutogen>
+              <configureArgs>
+                <arg>${jni.compiler.args.ldflags}</arg>
+                <arg>${jni.compiler.args.cflags}</arg>
+              </configureArgs>
+            </configuration>
+            <goals>
+              <goal>generate</goal>
+              <goal>build</goal>
+            </goals>
+            <phase>compile</phase>
+          </execution>
+        </executions>
+      </plugin>
+
+      <plugin>
+        <artifactId>maven-jar-plugin</artifactId>
+        <executions>
+          <!-- Generate the fallback JAR that does not contain the native library. -->
+          <execution>
+            <id>default-jar</id>
+            <configuration>
+              <excludes>
+                <exclude>META-INF/native/**</exclude>
+              </excludes>
+            </configuration>
+          </execution>
+          <!-- Generate the JAR that contains the native library in it. -->
+          <execution>
+            <id>native-jar</id>
+            <goals>
+              <goal>jar</goal>
+            </goals>
+            <configuration>
+              <archive>
+                <manifest>
+                  <addDefaultImplementationEntries>true</addDefaultImplementationEntries>
+                </manifest>
+                <manifestEntries>
+                  <Bundle-NativeCode>META-INF/native/libnetty-transport-native-kqueue.jnilib; osname=darwin, processor=x86_64"</Bundle-NativeCode>
+                </manifestEntries>
+                <index>true</index>
+                <manifestFile>${project.build.outputDirectory}/META-INF/MANIFEST.MF</manifestFile>
+              </archive>
+              <classifier>${jni.classifier}</classifier>
+            </configuration>
+          </execution>
+        </executions>
+      </plugin>
+    </plugins>
+  </build>
+</project>
+

transport-native-kqueue/src/main/c/netty_kqueue_bsdsocket.c

@@ -0,0 +1,299 @@
+/*
+ * Copyright 2016 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache License,
+ * version 2.0 (the "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at:
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+#include <stdlib.h>
+#include <errno.h>
+#include <string.h>
+#include <sys/types.h>
+#include <sys/malloc.h>
+#include <sys/socket.h>
+#include <sys/uio.h>
+#include <sys/un.h>
+#include <sys/ucred.h>
+#include <netinet/in.h>
+#include <netinet/tcp.h>
+#include "netty_unix_filedescriptor.h"
+#include "netty_unix_socket.h"
+#include "netty_unix_errors.h"
+#include "netty_unix_util.h"
+#include "netty_kqueue_bsdsocket.h"
+
+// Those are initialized in the init(...) method and cached for performance reasons
+static jclass stringCls = NULL;
+static jclass peerCredentialsClass = NULL;
+static jfieldID fileChannelFieldId = NULL;
+static jfieldID transferredFieldId = NULL;
+static jfieldID fdFieldId = NULL;
+static jfieldID fileDescriptorFieldId = NULL;
+static jmethodID peerCredentialsMethodId = NULL;
+
+// JNI Registered Methods Begin
+static jlong netty_kqueue_bsdsocket_sendFile(JNIEnv* env, jclass clazz, jint socketFd, jobject fileRegion, jlong base_off, jlong off, jlong len) {
+    jobject fileChannel = (*env)->GetObjectField(env, fileRegion, fileChannelFieldId);
+    if (fileChannel == NULL) {
+        netty_unix_errors_throwRuntimeException(env, "failed to get DefaultFileRegion.file");
+        return -1;
+    }
+    jobject fileDescriptor = (*env)->GetObjectField(env, fileChannel, fileDescriptorFieldId);
+    if (fileDescriptor == NULL) {
+        netty_unix_errors_throwRuntimeException(env, "failed to get FileChannelImpl.fd");
+        return -1;
+    }
+    jint srcFd = (*env)->GetIntField(env, fileDescriptor, fdFieldId);
+    if (srcFd == -1) {
+        netty_unix_errors_throwRuntimeException(env, "failed to get FileDescriptor.fd");
+        return -1;
+    }
+    const jlong lenBefore = len;
+    off_t sbytes;
+    int res, err;
+    do {
+#ifdef __APPLE__
+      // sbytes is an input (how many to write) and output (how many were written) parameter.
+      sbytes = len;
+      res = sendfile(srcFd, socketFd, base_off + off, &sbytes, NULL, 0);
+#else
+      sbytes = 0;
+      res = sendfile(srcFd, socketFd, base_off + off, len, NULL, &sbytes, 0);
+#endif
+      len -= sbytes;
+    } while (res < 0 && ((err = errno) == EINTR));
+    sbytes = lenBefore - len;
+    if (sbytes > 0) {
+        // update the transferred field in DefaultFileRegion
+        (*env)->SetLongField(env, fileRegion, transferredFieldId, off + sbytes);
+        return sbytes;
+    }
+    return res < 0 ? -err : 0;
+}
+
+static void netty_kqueue_bsdsocket_setAcceptFilter(JNIEnv* env, jclass clazz, jint fd, jstring afName, jstring afArg) {
+#ifdef SO_ACCEPTFILTER
+    struct accept_filter_arg af;
+    const char* tmpString = NULL;
+    af.af_name[0] = af.af_arg[0] ='\0';
+
+    tmpString = (*env)->GetStringUTFChars(env, afName, NULL);
+    strncat(af.af_name, tmpString, sizeof(af.af_name) / sizeof(af.af_name[0]));
+    (*env)->ReleaseStringUTFChars(env, afName, tmpString);
+
+    tmpString = (*env)->GetStringUTFChars(env, afArg, NULL);
+    strncat(af.af_arg, tmpString, sizeof(af.af_arg) / sizeof(af.af_arg[0]));
+    (*env)->ReleaseStringUTFChars(env, afArg, tmpString);
+
+    netty_unix_socket_setOption(env, fd, SOL_SOCKET, SO_ACCEPTFILTER, &af, sizeof(af));
+#else // No know replacement on MacOS
+    netty_unix_errors_throwChannelExceptionErrorNo(env, "setsockopt() failed: ", EINVAL);
+#endif
+}
+
+static jobjectArray netty_kqueue_bsdsocket_getAcceptFilter(JNIEnv* env, jclass clazz, jint fd) {
+#ifdef SO_ACCEPTFILTER
+    struct accept_filter_arg af;
+    if (netty_unix_socket_getOption(env, fd, SOL_SOCKET, SO_ACCEPTFILTER, &af, sizeof(af)) == -1) {
+        netty_unix_errors_throwChannelExceptionErrorNo(env, "getsockopt() failed: ", errno);
+        return NULL;
+    }
+    jobjectArray resultArray = (*env)->NewObjectArray(env, 2, stringCls, NULL);
+    (*env)->SetObjectArrayElement(env, resultArray, 0, (*env)->NewStringUTF(env, &af.af_name[0]));
+    (*env)->SetObjectArrayElement(env, resultArray, 1, (*env)->NewStringUTF(env, &af.af_arg[0]));
+    return resultArray;
+#else // No know replacement on MacOS
+    // Don't throw here because this is used when getting a list of all options.
+    return NULL;
+#endif
+}
+
+static void netty_kqueue_bsdsocket_setTcpNoPush(JNIEnv* env, jclass clazz, jint fd, jint optval) {
+    netty_unix_socket_setOption(env, fd, IPPROTO_TCP, TCP_NOPUSH, &optval, sizeof(optval));
+}
+
+static void netty_kqueue_bsdsocket_setSndLowAt(JNIEnv* env, jclass clazz, jint fd, jint optval) {
+    netty_unix_socket_setOption(env, fd, SOL_SOCKET, SO_SNDLOWAT, &optval, sizeof(optval));
+}
+
+static jint netty_kqueue_bsdsocket_getTcpNoPush(JNIEnv* env, jclass clazz, jint fd) {
+  int optval;
+  if (netty_unix_socket_getOption(env, fd, IPPROTO_TCP, TCP_NOPUSH, &optval, sizeof(optval)) == -1) {
+    return -1;
+  }
+  return optval;
+}
+
+static jint netty_kqueue_bsdsocket_getSndLowAt(JNIEnv* env, jclass clazz, jint fd) {
+  int optval;
+  if (netty_unix_socket_getOption(env, fd, SOL_SOCKET, SO_SNDLOWAT, &optval, sizeof(optval)) == -1) {
+    return -1;
+  }
+  return optval;
+}
+
+static jobject netty_kqueue_bsdsocket_getPeerCredentials(JNIEnv *env, jclass clazz, jint fd) {
+    struct xucred credentials;
+    // It has been observed on MacOS that this method can complete successfully but not set all fields of xucred.
+    credentials.cr_ngroups = 0;
+    if(netty_unix_socket_getOption(env,fd, SOL_SOCKET, LOCAL_PEERCRED, &credentials, sizeof (credentials)) == -1) {
+        return NULL;
+    }
+    jintArray gids = NULL;
+    if (credentials.cr_ngroups > 1) {
+        gids = (*env)->NewIntArray(env, credentials.cr_ngroups);
+        (*env)->SetIntArrayRegion(env, gids, 0, credentials.cr_ngroups, (jint*) credentials.cr_groups);
+    } else {
+        // It has been observed on MacOS that cr_ngroups may not be set, but the cr_gid field is set.
+        gids = (*env)->NewIntArray(env, 1);
+        (*env)->SetIntArrayRegion(env, gids, 0, 1, (jint*) &credentials.cr_gid);
+    }
+
+    // TODO: getting the PID may require reading/sending "ancillary data" via SCM_CREDENTIALS which is not desirable.
+    return (*env)->NewObject(env, peerCredentialsClass, peerCredentialsMethodId, 0, credentials.cr_uid, gids);
+}
+// JNI Registered Methods End
+
+// JNI Method Registration Table Begin
+static const JNINativeMethod fixed_method_table[] = {
+  { "setAcceptFilter", "(ILjava/lang/String;Ljava/lang/String;)V", (void *) netty_kqueue_bsdsocket_setAcceptFilter },
+  { "setTcpNoPush", "(II)V", (void *) netty_kqueue_bsdsocket_setTcpNoPush },
+  { "setSndLowAt", "(II)V", (void *) netty_kqueue_bsdsocket_setSndLowAt },
+  { "getAcceptFilter", "(I)[Ljava/lang/String;", (void *) netty_kqueue_bsdsocket_getAcceptFilter },
+  { "getTcpNoPush", "(I)I", (void *) netty_kqueue_bsdsocket_getTcpNoPush },
+  { "getSndLowAt", "(I)I", (void *) netty_kqueue_bsdsocket_getSndLowAt }
+};
+
+static const jint fixed_method_table_size = sizeof(fixed_method_table) / sizeof(fixed_method_table[0]);
+
+static jint dynamicMethodsTableSize() {
+    return fixed_method_table_size + 2;
+}
+
+static JNINativeMethod* createDynamicMethodsTable(const char* packagePrefix) {
+    JNINativeMethod* dynamicMethods = malloc(sizeof(JNINativeMethod) * dynamicMethodsTableSize());
+    memcpy(dynamicMethods, fixed_method_table, sizeof(fixed_method_table));
+    char* dynamicTypeName = netty_unix_util_prepend(packagePrefix, "io/netty/channel/DefaultFileRegion;JJJ)J");
+    JNINativeMethod* dynamicMethod = &dynamicMethods[fixed_method_table_size];
+    dynamicMethod->name = "sendFile";
+    dynamicMethod->signature = netty_unix_util_prepend("(IL", dynamicTypeName);
+    dynamicMethod->fnPtr = (void *) netty_kqueue_bsdsocket_sendFile;
+    free(dynamicTypeName);
+
+    ++dynamicMethod;
+    dynamicTypeName = netty_unix_util_prepend(packagePrefix, "io/netty/channel/unix/PeerCredentials;");
+    dynamicMethod->name = "getPeerCredentials";
+    dynamicMethod->signature = netty_unix_util_prepend("(I)L", dynamicTypeName);
+    dynamicMethod->fnPtr = (void *) netty_kqueue_bsdsocket_getPeerCredentials;
+    free(dynamicTypeName);
+
+    return dynamicMethods;
+}
+
+static void freeDynamicMethodsTable(JNINativeMethod* dynamicMethods) {
+    jint fullMethodTableSize = dynamicMethodsTableSize();
+    jint i = fixed_method_table_size;
+    for (; i < fullMethodTableSize; ++i) {
+        free(dynamicMethods[i].signature);
+    }
+    free(dynamicMethods);
+}
+// JNI Method Registration Table End
+
+jint netty_kqueue_bsdsocket_JNI_OnLoad(JNIEnv* env, const char* packagePrefix) {
+    // Register the methods which are not referenced by static member variables
+    JNINativeMethod* dynamicMethods = createDynamicMethodsTable(packagePrefix);
+    if (netty_unix_util_register_natives(env,
+            packagePrefix,
+            "io/netty/channel/kqueue/BsdSocket",
+            dynamicMethods,
+            dynamicMethodsTableSize()) != 0) {
+        freeDynamicMethodsTable(dynamicMethods);
+        return JNI_ERR;
+    }
+    freeDynamicMethodsTable(dynamicMethods);
+    dynamicMethods = NULL;
+
+    // Initialize this module
+    char* nettyClassName = netty_unix_util_prepend(packagePrefix, "io/netty/channel/DefaultFileRegion");
+    jclass fileRegionCls = (*env)->FindClass(env, nettyClassName);
+    free(nettyClassName);
+    nettyClassName = NULL;
+    if (fileRegionCls == NULL) {
+        return JNI_ERR;
+    }
+    fileChannelFieldId = (*env)->GetFieldID(env, fileRegionCls, "file", "Ljava/nio/channels/FileChannel;");
+    if (fileChannelFieldId == NULL) {
+        netty_unix_errors_throwRuntimeException(env, "failed to get field ID: DefaultFileRegion.file");
+        return JNI_ERR;
+    }
+    transferredFieldId = (*env)->GetFieldID(env, fileRegionCls, "transferred", "J");
+    if (transferredFieldId == NULL) {
+        netty_unix_errors_throwRuntimeException(env, "failed to get field ID: DefaultFileRegion.transferred");
+        return JNI_ERR;
+    }
+
+    jclass fileChannelCls = (*env)->FindClass(env, "sun/nio/ch/FileChannelImpl");
+    if (fileChannelCls == NULL) {
+        // pending exception...
+        return JNI_ERR;
+    }
+    fileDescriptorFieldId = (*env)->GetFieldID(env, fileChannelCls, "fd", "Ljava/io/FileDescriptor;");
+    if (fileDescriptorFieldId == NULL) {
+        netty_unix_errors_throwRuntimeException(env, "failed to get field ID: FileChannelImpl.fd");
+        return JNI_ERR;
+    }
+
+    jclass fileDescriptorCls = (*env)->FindClass(env, "java/io/FileDescriptor");
+    if (fileDescriptorCls == NULL) {
+        // pending exception...
+        return JNI_ERR;
+    }
+    fdFieldId = (*env)->GetFieldID(env, fileDescriptorCls, "fd", "I");
+    if (fdFieldId == NULL) {
+        netty_unix_errors_throwRuntimeException(env, "failed to get field ID: FileDescriptor.fd");
+        return JNI_ERR;
+    }
+    stringCls = (*env)->FindClass(env, "java/lang/String");
+    if (stringCls == NULL) {
+        // pending exception...
+        return JNI_ERR;
+    }
+
+    nettyClassName = netty_unix_util_prepend(packagePrefix, "io/netty/channel/unix/PeerCredentials");
+    jclass localPeerCredsClass = (*env)->FindClass(env, nettyClassName);
+    free(nettyClassName);
+    nettyClassName = NULL;
+    if (localPeerCredsClass == NULL) {
+        // pending exception...
+        return JNI_ERR;
+    }
+    peerCredentialsClass = (jclass) (*env)->NewGlobalRef(env, localPeerCredsClass);
+    if (peerCredentialsClass == NULL) {
+        // out-of-memory!
+        netty_unix_errors_throwOutOfMemoryError(env);
+        return JNI_ERR;
+    }
+    peerCredentialsMethodId = (*env)->GetMethodID(env, peerCredentialsClass, "<init>", "(II[I)V");
+    if (peerCredentialsMethodId == NULL) {
+        netty_unix_errors_throwRuntimeException(env, "failed to get method ID: PeerCredentials.<init>(int, int, int[])");
+        return JNI_ERR;
+    }
+
+    return JNI_VERSION_1_6;
+}
+
+void netty_kqueue_bsdsocket_JNI_OnUnLoad(JNIEnv* env) {
+    if (peerCredentialsClass != NULL) {
+        (*env)->DeleteGlobalRef(env, peerCredentialsClass);
+        peerCredentialsClass = NULL;
+    }
+}

transport-native-kqueue/src/main/c/netty_kqueue_bsdsocket.h

@@ -0,0 +1,25 @@
+/*
+ * Copyright 2016 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache License,
+ * version 2.0 (the "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at:
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+#ifndef NETTY_KQUEUE_BSDSOCKET_H_
+#define NETTY_KQUEUE_BSDSOCKET_H_
+
+#include <jni.h>
+
+// JNI initialization hooks. Users of this file are responsible for calling these in the JNI_OnLoad and JNI_OnUnload methods.
+jint netty_kqueue_bsdsocket_JNI_OnLoad(JNIEnv* env, const char* packagePrefix);
+void netty_kqueue_bsdsocket_JNI_OnUnLoad(JNIEnv* env);
+
+#endif /* NETTY_KQUEUE_BSDSOCKET_H_ */

transport-native-kqueue/src/main/c/netty_kqueue_eventarray.c

@@ -0,0 +1,124 @@
+/*
+ * Copyright 2016 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache License,
+ * version 2.0 (the "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at:
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+#include <stdlib.h>
+#include <string.h>
+#include <sys/types.h>
+#include <sys/event.h>
+#include <sys/time.h>
+#include "netty_unix_util.h"
+#include "netty_unix_errors.h"
+#include "netty_kqueue_eventarray.h"
+
+jfieldID kqueueJniPtrFieldId = NULL;
+
+static void netty_kqueue_eventarray_evSet(JNIEnv* env, jclass clzz, jlong keventAddress, jobject channel, jint ident, jshort filter, jshort flags, jint fflags) {
+    // Create a global pointer, cast it as a long, and retain it in java to re-use and free later.
+    jlong jniSelfPtr = (*env)->GetLongField(env, channel, kqueueJniPtrFieldId);
+    if (jniSelfPtr == 0) {
+        jniSelfPtr = (jlong) (*env)->NewGlobalRef(env, channel);
+        (*env)->SetLongField(env, channel, kqueueJniPtrFieldId, jniSelfPtr);
+    }
+    EV_SET((struct kevent*) keventAddress, ident, filter, flags, fflags, 0, (jobject) jniSelfPtr);
+}
+
+static jobject netty_kqueue_eventarray_getChannel(JNIEnv* env, jclass clazz, jlong keventAddress) {
+    struct kevent* event = (struct kevent*) keventAddress;
+    return event->udata == NULL ? NULL : (jobject) event->udata;
+}
+
+static void netty_kqueue_eventarray_deleteGlobalRefs(JNIEnv* env, jclass clazz, jlong channelAddressStart, jlong channelAddressEnd) {
+    // Iterate over an array of longs, which are really pointers to the jobject NewGlobalRef created above in evSet
+    // and delete each one. The field has already been set to 0 in java.
+    jlong* itr = (jlong*) channelAddressStart;
+    const jlong* end = (jlong*) channelAddressEnd;
+    for (; itr != end; ++itr) {
+        (*env)->DeleteGlobalRef(env, (jobject) *itr);
+    }
+}
+
+// JNI Method Registration Table Begin
+static const JNINativeMethod fixed_method_table[] = {
+  { "deleteGlobalRefs", "(JJ)V", (void *) netty_kqueue_eventarray_deleteGlobalRefs }
+  // "evSet" has a dynamic signature
+  // "getChannel" has a dynamic signature
+};
+static const jint fixed_method_table_size = sizeof(fixed_method_table) / sizeof(fixed_method_table[0]);
+
+static jint dynamicMethodsTableSize() {
+    return fixed_method_table_size + 2;
+}
+
+static JNINativeMethod* createDynamicMethodsTable(const char* packagePrefix) {
+    JNINativeMethod* dynamicMethods = malloc(sizeof(JNINativeMethod) * dynamicMethodsTableSize());
+    memcpy(dynamicMethods, fixed_method_table, sizeof(fixed_method_table));
+    char* dynamicTypeName = netty_unix_util_prepend(packagePrefix, "io/netty/channel/kqueue/AbstractKQueueChannel;ISSI)V");
+    JNINativeMethod* dynamicMethod = &dynamicMethods[fixed_method_table_size];
+    dynamicMethod->name = "evSet";
+    dynamicMethod->signature = netty_unix_util_prepend("(JL", dynamicTypeName);
+    dynamicMethod->fnPtr = (void *) netty_kqueue_eventarray_evSet;
+    free(dynamicTypeName);
+
+    ++dynamicMethod;
+    dynamicTypeName = netty_unix_util_prepend(packagePrefix, "io/netty/channel/kqueue/AbstractKQueueChannel;");
+    dynamicMethod->name = "getChannel";
+    dynamicMethod->signature = netty_unix_util_prepend("(J)L", dynamicTypeName);
+    dynamicMethod->fnPtr = (void *) netty_kqueue_eventarray_getChannel;
+    free(dynamicTypeName);
+    return dynamicMethods;
+}
+
+static void freeDynamicMethodsTable(JNINativeMethod* dynamicMethods) {
+    jint fullMethodTableSize = dynamicMethodsTableSize();
+    jint i = fixed_method_table_size;
+    for (; i < fullMethodTableSize; ++i) {
+        free(dynamicMethods[i].signature);
+    }
+    free(dynamicMethods);
+}
+// JNI Method Registration Table End
+
+jint netty_kqueue_eventarray_JNI_OnLoad(JNIEnv* env, const char* packagePrefix) {
+    JNINativeMethod* dynamicMethods = createDynamicMethodsTable(packagePrefix);
+    if (netty_unix_util_register_natives(env,
+            packagePrefix,
+            "io/netty/channel/kqueue/KQueueEventArray",
+            dynamicMethods,
+            dynamicMethodsTableSize()) != 0) {
+        freeDynamicMethodsTable(dynamicMethods);
+        return JNI_ERR;
+    }
+    freeDynamicMethodsTable(dynamicMethods);
+    dynamicMethods = NULL;
+
+    char* nettyClassName = netty_unix_util_prepend(packagePrefix, "io/netty/channel/kqueue/AbstractKQueueChannel");
+    jclass kqueueChannelCls = (*env)->FindClass(env, nettyClassName);
+    free(nettyClassName);
+    nettyClassName = NULL;
+    if (kqueueChannelCls == NULL) {
+        return JNI_ERR;
+    }
+
+    kqueueJniPtrFieldId = (*env)->GetFieldID(env, kqueueChannelCls, "jniSelfPtr", "J");
+    if (kqueueJniPtrFieldId == NULL) {
+        netty_unix_errors_throwRuntimeException(env, "failed to get field ID: AbstractKQueueChannel.jniSelfPtr");
+        return JNI_ERR;
+    }
+
+    return JNI_VERSION_1_6;
+}
+
+void netty_kqueue_eventarray_JNI_OnUnLoad(JNIEnv* env) {
+}

transport-native-kqueue/src/main/c/netty_kqueue_eventarray.h

@@ -0,0 +1,25 @@
+/*
+ * Copyright 2016 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache License,
+ * version 2.0 (the "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at:
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+#ifndef NETTY_KQUEUE_EVENTARRAY_H_
+#define NETTY_KQUEUE_EVENTARRAY_H_
+
+#include <jni.h>
+
+// JNI initialization hooks. Users of this file are responsible for calling these in the JNI_OnLoad and JNI_OnUnload methods.
+jint netty_kqueue_eventarray_JNI_OnLoad(JNIEnv* env, const char* packagePrefix);
+void netty_kqueue_eventarray_JNI_OnUnLoad(JNIEnv* env);
+
+#endif /* NETTY_KQUEUE_EVENTARRAY_H_ */

transport-native-kqueue/src/main/c/netty_kqueue_native.c

@@ -0,0 +1,307 @@
+/*
+ * Copyright 2016 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache License,
+ * version 2.0 (the "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at:
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+#include <errno.h>
+#include <netdb.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <dlfcn.h>
+#include <stddef.h>
+#include <time.h>
+#include <sys/event.h>
+#include <sys/socket.h>
+#include <sys/time.h>
+#include "netty_unix_filedescriptor.h"
+#include "netty_unix_socket.h"
+#include "netty_unix_errors.h"
+#include "netty_unix_util.h"
+#include "netty_unix_limits.h"
+#include "netty_kqueue_bsdsocket.h"
+#include "netty_kqueue_eventarray.h"
+
+clockid_t waitClockId = 0; // initialized by netty_unix_util_initialize_wait_clock
+
+static jint netty_kqueue_native_kqueueCreate(JNIEnv* env, jclass clazz) {
+    jint kq = kqueue();
+    if (kq < 0) {
+      netty_unix_errors_throwChannelExceptionErrorNo(env, "kqueue() failed: ", errno);
+    }
+    return kq;
+}
+
+static jint netty_kqueue_native_keventChangeSingleUserEvent(jint kqueueFd, struct kevent* userEvent) {
+    int result, err;
+    result = kevent(kqueueFd, userEvent, 1, NULL, 0, NULL);
+    if (result < 0) {
+        // https://www.freebsd.org/cgi/man.cgi?query=kqueue&sektion=2
+        // When kevent() call fails with EINTR error, all changes in the changelist have been applied.
+        return (err = errno) == EINTR ? 0 : -err;
+    }
+
+    return result;
+}
+
+static jint netty_kqueue_native_keventTriggerUserEvent(JNIEnv* env, jclass clazz, jint kqueueFd, jint ident) {
+    struct kevent userEvent;
+    EV_SET(&userEvent, ident, EVFILT_USER, 0, NOTE_TRIGGER | NOTE_FFNOP, 0, NULL);
+    return netty_kqueue_native_keventChangeSingleUserEvent(kqueueFd, &userEvent);
+}
+
+static jint netty_kqueue_native_keventAddUserEvent(JNIEnv* env, jclass clazz, jint kqueueFd, jint ident) {
+    struct kevent userEvent;
+    EV_SET(&userEvent, ident, EVFILT_USER, EV_ADD | EV_ENABLE | EV_CLEAR, NOTE_FFNOP, 0, NULL);
+    return netty_kqueue_native_keventChangeSingleUserEvent(kqueueFd, &userEvent);
+}
+
+static jint netty_kqueue_native_keventWait(JNIEnv* env, jclass clazz, jint kqueueFd, jlong changeListAddress, jint changeListLength,
+                                           jlong eventListAddress, jint eventListLength, jint tvSec, jint tvNsec) {
+    struct kevent* changeList = (struct kevent*) changeListAddress;
+    struct kevent* eventList = (struct kevent*) eventListAddress;
+    struct timespec beforeTs, nowTs, timeoutTs;
+    int result, err;
+
+    timeoutTs.tv_sec = tvSec;
+    timeoutTs.tv_nsec = tvNsec;
+
+    // Negatives = wait indefinitely, Zeros = poll (aka return immediately).
+    if ((tvSec == 0 && tvNsec == 0) || tvSec < 0 || tvNsec < 0) {
+        const struct timespec* fixedTs = (tvSec == 0 && tvNsec == 0) ? &timeoutTs : NULL;
+        for (;;) {
+            result = kevent(kqueueFd, changeList, changeListLength, eventList, eventListLength, fixedTs);
+            if (result >= 0) {
+                return result;
+            }
+            if ((err = errno) != EINTR) {
+                return -err;
+            }
+
+            // https://www.freebsd.org/cgi/man.cgi?query=kqueue&sektion=2
+            // When kevent() call fails with EINTR error, all changes in the changelist have been applied.
+            changeListLength = 0;
+        }
+    }
+
+    // Wait with a timeout value.
+    netty_unix_util_clock_gettime(waitClockId, &beforeTs);
+    for (;;) {
+        result = kevent(kqueueFd, changeList, changeListLength, eventList, eventListLength, &timeoutTs);
+        if (result >= 0) {
+            return result;
+        }
+        if ((err = errno) != EINTR) {
+            return -err;
+        }
+
+        netty_unix_util_clock_gettime(waitClockId, &nowTs);
+        // beforeTs will store the time difference to check for overflow
+        beforeTs.tv_sec = nowTs.tv_sec - beforeTs.tv_sec;
+        beforeTs.tv_nsec = nowTs.tv_nsec - beforeTs.tv_nsec;
+        // Now subtract the time difference
+        timeoutTs.tv_sec -= beforeTs.tv_sec;
+        timeoutTs.tv_nsec -= beforeTs.tv_nsec;
+        if (beforeTs.tv_sec < 0 || beforeTs.tv_nsec < 0 || (timeoutTs.tv_sec <= 0 && timeoutTs.tv_nsec <= 0)) {
+            return 0;
+        }
+        beforeTs = nowTs;
+        // https://www.freebsd.org/cgi/man.cgi?query=kqueue&sektion=2
+        // When kevent() call fails with EINTR error, all changes in the changelist have been applied.
+        changeListLength = 0;
+    }
+}
+
+static jint netty_kqueue_native_sizeofKEvent(JNIEnv* env, jclass clazz) {
+    return sizeof(struct kevent);
+}
+
+static jint netty_kqueue_native_offsetofKEventIdent(JNIEnv* env, jclass clazz) {
+    return offsetof(struct kevent, ident);
+}
+
+static jint netty_kqueue_native_offsetofKEventFlags(JNIEnv* env, jclass clazz) {
+    return offsetof(struct kevent, flags);
+}
+
+static jint netty_kqueue_native_offsetofKEventFilter(JNIEnv* env, jclass clazz) {
+    return offsetof(struct kevent, filter);
+}
+
+static jint netty_kqueue_native_offsetofKEventFFlags(JNIEnv* env, jclass clazz) {
+    return offsetof(struct kevent, fflags);
+}
+
+static jint netty_kqueue_native_offsetofKeventData(JNIEnv* env, jclass clazz) {
+    return offsetof(struct kevent, data);
+}
+
+static jshort netty_kqueue_native_evfiltRead(JNIEnv* env, jclass clazz) {
+    return EVFILT_READ;
+}
+
+static jshort netty_kqueue_native_evfiltWrite(JNIEnv* env, jclass clazz) {
+    return EVFILT_WRITE;
+}
+
+static jshort netty_kqueue_native_evfiltUser(JNIEnv* env, jclass clazz) {
+    return EVFILT_USER;
+}
+
+static jshort netty_kqueue_native_evAdd(JNIEnv* env, jclass clazz) {
+   return EV_ADD;
+}
+
+static jshort netty_kqueue_native_evEnable(JNIEnv* env, jclass clazz) {
+   return EV_ENABLE;
+}
+
+static jshort netty_kqueue_native_evDisable(JNIEnv* env, jclass clazz) {
+   return EV_DISABLE;
+}
+
+static jshort netty_kqueue_native_evDelete(JNIEnv* env, jclass clazz) {
+   return EV_DELETE;
+}
+
+static jshort netty_kqueue_native_evClear(JNIEnv* env, jclass clazz) {
+   return EV_CLEAR;
+}
+
+static jshort netty_kqueue_native_evEOF(JNIEnv* env, jclass clazz) {
+   return EV_EOF;
+}
+
+static jshort netty_kqueue_native_evError(JNIEnv* env, jclass clazz) {
+   return EV_ERROR;
+}
+
+// JNI Method Registration Table Begin
+static const JNINativeMethod statically_referenced_fixed_method_table[] = {
+  { "evfiltRead", "()S", (void *) netty_kqueue_native_evfiltRead },
+  { "evfiltWrite", "()S", (void *) netty_kqueue_native_evfiltWrite },
+  { "evfiltUser", "()S", (void *) netty_kqueue_native_evfiltUser },
+  { "evAdd", "()S", (void *) netty_kqueue_native_evAdd },
+  { "evEnable", "()S", (void *) netty_kqueue_native_evEnable },
+  { "evDisable", "()S", (void *) netty_kqueue_native_evDisable },
+  { "evDelete", "()S", (void *) netty_kqueue_native_evDelete },
+  { "evClear", "()S", (void *) netty_kqueue_native_evClear },
+  { "evEOF", "()S", (void *) netty_kqueue_native_evEOF },
+  { "evError", "()S", (void *) netty_kqueue_native_evError }
+};
+static const jint statically_referenced_fixed_method_table_size = sizeof(statically_referenced_fixed_method_table) / sizeof(statically_referenced_fixed_method_table[0]);
+static const JNINativeMethod fixed_method_table[] = {
+  { "kqueueCreate", "()I", (void *) netty_kqueue_native_kqueueCreate },
+  { "keventTriggerUserEvent", "(II)I", (void *) netty_kqueue_native_keventTriggerUserEvent },
+  { "keventAddUserEvent", "(II)I", (void *) netty_kqueue_native_keventAddUserEvent },
+  { "keventWait", "(IJIJIII)I", (void *) netty_kqueue_native_keventWait },
+  { "sizeofKEvent", "()I", (void *) netty_kqueue_native_sizeofKEvent },
+  { "offsetofKEventIdent", "()I", (void *) netty_kqueue_native_offsetofKEventIdent },
+  { "offsetofKEventFlags", "()I", (void *) netty_kqueue_native_offsetofKEventFlags },
+  { "offsetofKEventFFlags", "()I", (void *) netty_kqueue_native_offsetofKEventFFlags },
+  { "offsetofKEventFilter", "()I", (void *) netty_kqueue_native_offsetofKEventFilter },
+  { "offsetofKeventData", "()I", (void *) netty_kqueue_native_offsetofKeventData }
+};
+static const jint fixed_method_table_size = sizeof(fixed_method_table) / sizeof(fixed_method_table[0]);
+// JNI Method Registration Table End
+
+static jint netty_kqueue_native_JNI_OnLoad(JNIEnv* env, const char* packagePrefix) {
+    // We must register the statically referenced methods first!
+    if (netty_unix_util_register_natives(env,
+            packagePrefix,
+            "io/netty/channel/kqueue/KQueueStaticallyReferencedJniMethods",
+            statically_referenced_fixed_method_table,
+            statically_referenced_fixed_method_table_size) != 0) {
+        return JNI_ERR;
+    }
+    // Register the methods which are not referenced by static member variables
+    if (netty_unix_util_register_natives(env, packagePrefix, "io/netty/channel/kqueue/Native", fixed_method_table, fixed_method_table_size) != 0) {
+        return JNI_ERR;
+    }
+    // Load all c modules that we depend upon
+    if (netty_unix_limits_JNI_OnLoad(env, packagePrefix) == JNI_ERR) {
+        return JNI_ERR;
+    }
+    if (netty_unix_errors_JNI_OnLoad(env, packagePrefix) == JNI_ERR) {
+        return JNI_ERR;
+    }
+    if (netty_unix_filedescriptor_JNI_OnLoad(env, packagePrefix) == JNI_ERR) {
+        return JNI_ERR;
+    }
+    if (netty_unix_socket_JNI_OnLoad(env, packagePrefix) == JNI_ERR) {
+        return JNI_ERR;
+    }
+    if (netty_kqueue_bsdsocket_JNI_OnLoad(env, packagePrefix) == JNI_ERR) {
+        return JNI_ERR;
+    }
+    if (netty_kqueue_eventarray_JNI_OnLoad(env, packagePrefix) == JNI_ERR) {
+        return JNI_ERR;
+    }
+    // Initialize this module
+
+    if (!netty_unix_util_initialize_wait_clock(&waitClockId)) {
+      fprintf(stderr, "FATAL: could not find a clock for clock_gettime!\n");
+      return JNI_ERR;
+    }
+
+    return JNI_VERSION_1_6;
+}
+
+static void netty_kqueue_native_JNI_OnUnLoad(JNIEnv* env) {
+    netty_unix_limits_JNI_OnUnLoad(env);
+    netty_unix_errors_JNI_OnUnLoad(env);
+    netty_unix_filedescriptor_JNI_OnUnLoad(env);
+    netty_unix_socket_JNI_OnUnLoad(env);
+    netty_kqueue_bsdsocket_JNI_OnUnLoad(env);
+    netty_kqueue_eventarray_JNI_OnUnLoad(env);
+}
+
+jint JNI_OnLoad(JavaVM* vm, void* reserved) {
+    JNIEnv* env;
+    if ((*vm)->GetEnv(vm, (void**) &env, JNI_VERSION_1_6) != JNI_OK) {
+        return JNI_ERR;
+    }
+
+    Dl_info dlinfo;
+    jint status = 0;
+    // We need to use an address of a function that is uniquely part of this library, so choose a static
+    // function. See https://github.com/netty/netty/issues/4840.
+    if (!dladdr((void*) netty_kqueue_native_JNI_OnUnLoad, &dlinfo)) {
+        fprintf(stderr, "FATAL: transport-native-kqueue JNI call to dladdr failed!\n");
+        return JNI_ERR;
+    }
+    char* packagePrefix = netty_unix_util_parse_package_prefix(dlinfo.dli_fname, "netty-transport-native-kqueue", &status);
+    if (status == JNI_ERR) {
+        fprintf(stderr, "FATAL: transport-native-kqueue JNI encountered unexpected dlinfo.dli_fname: %s\n", dlinfo.dli_fname);
+        return JNI_ERR;
+    }
+
+    jint ret = netty_kqueue_native_JNI_OnLoad(env, packagePrefix);
+
+    if (packagePrefix != NULL) {
+      free(packagePrefix);
+      packagePrefix = NULL;
+    }
+
+    return ret;
+}
+
+void JNI_OnUnload(JavaVM* vm, void* reserved) {
+    JNIEnv* env;
+    if ((*vm)->GetEnv(vm, (void**) &env, JNI_VERSION_1_6) != JNI_OK) {
+        // Something is wrong but nothing we can do about this :(
+        return;
+    }
+    netty_kqueue_native_JNI_OnUnLoad(env);
+}

transport-native-kqueue/src/main/java/io/netty/channel/kqueue/AbstractKQueueChannel.java

@@ -0,0 +1,470 @@
+/*
+ * Copyright 2016 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache License,
+ * version 2.0 (the "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at:
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+package io.netty.channel.kqueue;
+
+import io.netty.buffer.ByteBuf;
+import io.netty.buffer.ByteBufAllocator;
+import io.netty.buffer.ByteBufUtil;
+import io.netty.buffer.Unpooled;
+import io.netty.channel.AbstractChannel;
+import io.netty.channel.Channel;
+import io.netty.channel.ChannelConfig;
+import io.netty.channel.ChannelMetadata;
+import io.netty.channel.EventLoop;
+import io.netty.channel.RecvByteBufAllocator;
+import io.netty.channel.socket.ChannelInputShutdownEvent;
+import io.netty.channel.socket.ChannelInputShutdownReadComplete;
+import io.netty.channel.unix.FileDescriptor;
+import io.netty.channel.unix.UnixChannel;
+import io.netty.util.ReferenceCountUtil;
+
+import java.io.IOException;
+import java.net.InetSocketAddress;
+import java.nio.ByteBuffer;
+import java.nio.channels.NotYetConnectedException;
+import java.nio.channels.UnresolvedAddressException;
+
+import static io.netty.util.internal.ObjectUtil.checkNotNull;
+
+abstract class AbstractKQueueChannel extends AbstractChannel implements UnixChannel {
+    private static final ChannelMetadata METADATA = new ChannelMetadata(false);
+    final BsdSocket socket;
+    private boolean readFilterEnabled = true;
+    private boolean writeFilterEnabled;
+    boolean readReadyRunnablePending;
+    boolean inputClosedSeenErrorOnRead;
+    /**
+     * This member variable means we don't have to have a map in {@link KQueueEventLoop} which associates the FDs
+     * from kqueue to instances of this class. This field will be initialized by JNI when modifying kqueue events.
+     * If there is no global reference when JNI gets a kqueue evSet call (aka this field is 0) then a global reference
+     * will be created and the address will be saved in this member variable. Then when we process a kevent in Java
+     * we can ask JNI to give us the {@link AbstractKQueueChannel} that corresponds to that event.
+     */
+    long jniSelfPtr;
+
+    protected volatile boolean active;
+
+    AbstractKQueueChannel(Channel parent, BsdSocket fd, boolean active) {
+        this(parent, fd, active, false);
+    }
+
+    AbstractKQueueChannel(Channel parent, BsdSocket fd, boolean active, boolean writeFilterEnabled) {
+        super(parent);
+        socket = checkNotNull(fd, "fd");
+        this.active = active;
+        this.writeFilterEnabled = writeFilterEnabled;
+    }
+
+    @Override
+    public final FileDescriptor fd() {
+        return socket;
+    }
+
+    @Override
+    public boolean isActive() {
+        return active;
+    }
+
+    @Override
+    public ChannelMetadata metadata() {
+        return METADATA;
+    }
+
+    @Override
+    protected void doClose() throws Exception {
+        active = false;
+        // Even if we allow half closed sockets we should give up on reading. Otherwise we may allow a read attempt on a
+        // socket which has not even been connected yet. This has been observed to block during unit tests.
+        inputClosedSeenErrorOnRead = true;
+        // The FD will be closed, which will take of deleting from kqueue.
+        readFilterEnabled = writeFilterEnabled = false;
+        try {
+            ((KQueueEventLoop) eventLoop()).remove(this);
+        } finally {
+            socket.close();
+        }
+    }
+
+    @Override
+    protected void doDisconnect() throws Exception {
+        doClose();
+    }
+
+    @Override
+    protected boolean isCompatible(EventLoop loop) {
+        return loop instanceof KQueueEventLoop;
+    }
+
+    @Override
+    public boolean isOpen() {
+        return socket.isOpen();
+    }
+
+    @Override
+    protected void doDeregister() throws Exception {
+        // Make sure we unregister our filters from kqueue!
+        readFilter(false);
+        writeFilter(false);
+
+        ((KQueueEventLoop) eventLoop()).remove(this);
+
+        // Set the filters back to the initial state in case this channel is registered with another event loop.
+        readFilterEnabled = true;
+    }
+
+    @Override
+    protected final void doBeginRead() throws Exception {
+        // Channel.read() or ChannelHandlerContext.read() was called
+        final AbstractKQueueUnsafe unsafe = (AbstractKQueueUnsafe) unsafe();
+        unsafe.readPending = true;
+
+        // We must set the read flag here as it is possible the user didn't read in the last read loop, the
+        // executeReadReadyRunnable could read nothing, and if the user doesn't explicitly call read they will
+        // never get data after this.
+        readFilter(true);
+
+        // If auto read was toggled off on the last read loop then we may not be notified
+        // again if we didn't consume all the data. So we force a read operation here if there maybe more data.
+        if (unsafe.maybeMoreDataToRead) {
+            unsafe.executeReadReadyRunnable(config());
+        }
+    }
+
+    @Override
+    protected void doRegister() throws Exception {
+        // Just in case the previous EventLoop was shutdown abruptly, or an event is still pending on the old EventLoop
+        // make sure the readReadyRunnablePending variable is reset so we will be able to execute the Runnable on the
+        // new EventLoop.
+        readReadyRunnablePending = false;
+        // Add the write event first so we get notified of connection refused on the client side!
+        if (writeFilterEnabled) {
+            evSet0(Native.EVFILT_WRITE, Native.EV_ADD_CLEAR_ENABLE);
+        }
+        if (readFilterEnabled) {
+            evSet0(Native.EVFILT_READ, Native.EV_ADD_CLEAR_ENABLE);
+        }
+    }
+
+    @Override
+    protected abstract AbstractKQueueUnsafe newUnsafe();
+
+    @Override
+    public abstract KQueueChannelConfig config();
+
+    /**
+     * Returns an off-heap copy of the specified {@link ByteBuf}, and releases the original one.
+     */
+    protected final ByteBuf newDirectBuffer(ByteBuf buf) {
+        return newDirectBuffer(buf, buf);
+    }
+
+    /**
+     * Returns an off-heap copy of the specified {@link ByteBuf}, and releases the specified holder.
+     * The caller must ensure that the holder releases the original {@link ByteBuf} when the holder is released by
+     * this method.
+     */
+    protected final ByteBuf newDirectBuffer(Object holder, ByteBuf buf) {
+        final int readableBytes = buf.readableBytes();
+        if (readableBytes == 0) {
+            ReferenceCountUtil.safeRelease(holder);
+            return Unpooled.EMPTY_BUFFER;
+        }
+
+        final ByteBufAllocator alloc = alloc();
+        if (alloc.isDirectBufferPooled()) {
+            return newDirectBuffer0(holder, buf, alloc, readableBytes);
+        }
+
+        final ByteBuf directBuf = ByteBufUtil.threadLocalDirectBuffer();
+        if (directBuf == null) {
+            return newDirectBuffer0(holder, buf, alloc, readableBytes);
+        }
+
+        directBuf.writeBytes(buf, buf.readerIndex(), readableBytes);
+        ReferenceCountUtil.safeRelease(holder);
+        return directBuf;
+    }
+
+    private static ByteBuf newDirectBuffer0(Object holder, ByteBuf buf, ByteBufAllocator alloc, int capacity) {
+        final ByteBuf directBuf = alloc.directBuffer(capacity);
+        directBuf.writeBytes(buf, buf.readerIndex(), capacity);
+        ReferenceCountUtil.safeRelease(holder);
+        return directBuf;
+    }
+
+    protected static void checkResolvable(InetSocketAddress addr) {
+        if (addr.isUnresolved()) {
+            throw new UnresolvedAddressException();
+        }
+    }
+
+    /**
+     * Read bytes into the given {@link ByteBuf} and return the amount.
+     */
+    protected final int doReadBytes(ByteBuf byteBuf) throws Exception {
+        int writerIndex = byteBuf.writerIndex();
+        int localReadAmount;
+        unsafe().recvBufAllocHandle().attemptedBytesRead(byteBuf.writableBytes());
+        if (byteBuf.hasMemoryAddress()) {
+            localReadAmount = socket.readAddress(byteBuf.memoryAddress(), writerIndex, byteBuf.capacity());
+        } else {
+            ByteBuffer buf = byteBuf.internalNioBuffer(writerIndex, byteBuf.writableBytes());
+            localReadAmount = socket.read(buf, buf.position(), buf.limit());
+        }
+        if (localReadAmount > 0) {
+            byteBuf.writerIndex(writerIndex + localReadAmount);
+        }
+        return localReadAmount;
+    }
+
+    protected final int doWriteBytes(ByteBuf buf, int writeSpinCount) throws Exception {
+        int readableBytes = buf.readableBytes();
+        int writtenBytes = 0;
+        if (buf.hasMemoryAddress()) {
+            long memoryAddress = buf.memoryAddress();
+            int readerIndex = buf.readerIndex();
+            int writerIndex = buf.writerIndex();
+            for (int i = writeSpinCount; i > 0; --i) {
+                int localFlushedAmount = socket.writeAddress(memoryAddress, readerIndex, writerIndex);
+                if (localFlushedAmount > 0) {
+                    writtenBytes += localFlushedAmount;
+                    if (writtenBytes == readableBytes) {
+                        return writtenBytes;
+                    }
+                    readerIndex += localFlushedAmount;
+                } else {
+                    break;
+                }
+            }
+        } else {
+            ByteBuffer nioBuf;
+            if (buf.nioBufferCount() == 1) {
+                nioBuf = buf.internalNioBuffer(buf.readerIndex(), buf.readableBytes());
+            } else {
+                nioBuf = buf.nioBuffer();
+            }
+            for (int i = writeSpinCount; i > 0; --i) {
+                int pos = nioBuf.position();
+                int limit = nioBuf.limit();
+                int localFlushedAmount = socket.write(nioBuf, pos, limit);
+                if (localFlushedAmount > 0) {
+                    nioBuf.position(pos + localFlushedAmount);
+                    writtenBytes += localFlushedAmount;
+                    if (writtenBytes == readableBytes) {
+                        return writtenBytes;
+                    }
+                } else {
+                    break;
+                }
+            }
+        }
+        if (writtenBytes < readableBytes) {
+            // Returned EAGAIN need to wait until we are allowed to write again.
+            writeFilter(true);
+        }
+        return writtenBytes;
+    }
+
+    final boolean shouldBreakReadReady(ChannelConfig config) {
+        return socket.isInputShutdown() && (inputClosedSeenErrorOnRead || !isAllowHalfClosure(config));
+    }
+
+    final boolean isAllowHalfClosure(ChannelConfig config) {
+        return config instanceof KQueueSocketChannelConfig &&
+                ((KQueueSocketChannelConfig) config).isAllowHalfClosure();
+    }
+
+    final void clearReadFilter() {
+        // Only clear if registered with an EventLoop as otherwise
+        if (isRegistered()) {
+            final EventLoop loop = eventLoop();
+            final AbstractKQueueUnsafe unsafe = (AbstractKQueueUnsafe) unsafe();
+            if (loop.inEventLoop()) {
+                unsafe.clearReadFilter0();
+            } else {
+                // schedule a task to clear the EPOLLIN as it is not safe to modify it directly
+                loop.execute(new Runnable() {
+                    @Override
+                    public void run() {
+                        if (!unsafe.readPending && !config().isAutoRead()) {
+                            // Still no read triggered so clear it now
+                            unsafe.clearReadFilter0();
+                        }
+                    }
+                });
+            }
+        } else  {
+            // The EventLoop is not registered atm so just update the flags so the correct value
+            // will be used once the channel is registered
+            readFilterEnabled = false;
+        }
+    }
+
+    void readFilter(boolean readFilterEnabled) throws IOException {
+        if (this.readFilterEnabled != readFilterEnabled) {
+            this.readFilterEnabled = readFilterEnabled;
+            evSet(Native.EVFILT_READ, readFilterEnabled ? Native.EV_ADD_CLEAR_ENABLE : Native.EV_DELETE_DISABLE);
+        }
+    }
+
+    void writeFilter(boolean writeFilterEnabled) throws IOException {
+        if (this.writeFilterEnabled != writeFilterEnabled) {
+            this.writeFilterEnabled = writeFilterEnabled;
+            evSet(Native.EVFILT_WRITE, writeFilterEnabled ? Native.EV_ADD_CLEAR_ENABLE : Native.EV_DELETE_DISABLE);
+        }
+    }
+
+    private void evSet(short filter, short flags) {
+        if (isOpen() && isRegistered()) {
+            evSet0(filter, flags);
+        }
+    }
+
+    private void evSet0(short filter, short flags) {
+        ((KQueueEventLoop) eventLoop()).evSet(this, filter, flags, 0);
+    }
+
+    abstract class AbstractKQueueUnsafe extends AbstractUnsafe {
+        boolean readPending;
+        boolean maybeMoreDataToRead;
+        private KQueueRecvByteAllocatorHandle allocHandle;
+        private final Runnable readReadyRunnable = new Runnable() {
+            @Override
+            public void run() {
+                readReadyRunnablePending = false;
+                readReady(recvBufAllocHandle());
+            }
+        };
+
+        final void readReady(long numberBytesPending) {
+            KQueueRecvByteAllocatorHandle allocHandle = recvBufAllocHandle();
+            allocHandle.numberBytesPending(numberBytesPending);
+            readReady(allocHandle);
+        }
+
+        abstract void readReady(KQueueRecvByteAllocatorHandle allocHandle);
+
+        final void readReadyBefore() { maybeMoreDataToRead = false; }
+
+        final void readReadyFinally(ChannelConfig config) {
+            maybeMoreDataToRead = allocHandle.maybeMoreDataToRead();
+            // Check if there is a readPending which was not processed yet.
+            // This could be for two reasons:
+            // * The user called Channel.read() or ChannelHandlerContext.read() in channelRead(...) method
+            // * The user called Channel.read() or ChannelHandlerContext.read() in channelReadComplete(...) method
+            //
+            // See https://github.com/netty/netty/issues/2254
+            if (!readPending && !config.isAutoRead()) {
+                clearReadFilter0();
+            } else if (readPending && maybeMoreDataToRead) {
+                // trigger a read again as there may be something left to read and because of ET we
+                // will not get notified again until we read everything from the socket
+                //
+                // It is possible the last fireChannelRead call could cause the user to call read() again, or if
+                // autoRead is true the call to channelReadComplete would also call read, but maybeMoreDataToRead is set
+                // to false before every read operation to prevent re-entry into readReady() we will not read from
+                // the underlying OS again unless the user happens to call read again.
+                executeReadReadyRunnable(config);
+            }
+        }
+
+        void writeReady() {
+            if (socket.isOutputShutdown()) {
+                return;
+            }
+            // directly call super.flush0() to force a flush now
+            super.flush0();
+        }
+
+        /**
+         * Shutdown the input side of the channel.
+         */
+        void shutdownInput(boolean readEOF) {
+            if (!socket.isInputShutdown()) {
+                if (isAllowHalfClosure(config())) {
+                    try {
+                        socket.shutdown(true, false);
+                    } catch (IOException ignored) {
+                        // We attempted to shutdown and failed, which means the input has already effectively been
+                        // shutdown.
+                        fireEventAndClose(ChannelInputShutdownEvent.INSTANCE);
+                        return;
+                    } catch (NotYetConnectedException ignore) {
+                        // We attempted to shutdown and failed, which means the input has already effectively been
+                        // shutdown.
+                    }
+                    pipeline().fireUserEventTriggered(ChannelInputShutdownEvent.INSTANCE);
+                } else {
+                    close(voidPromise());
+                }
+            } else if (!readEOF) {
+                inputClosedSeenErrorOnRead = true;
+                pipeline().fireUserEventTriggered(ChannelInputShutdownReadComplete.INSTANCE);
+            }
+        }
+
+        final void readEOF() {
+            // This must happen before we attempt to read. This will ensure reading continues until an error occurs.
+            final KQueueRecvByteAllocatorHandle allocHandle = recvBufAllocHandle();
+            allocHandle.readEOF();
+
+            if (isActive()) {
+                // If it is still active, we need to call readReady as otherwise we may miss to
+                // read pending data from the underlying file descriptor.
+                // See https://github.com/netty/netty/issues/3709
+                readReady(allocHandle);
+            } else {
+                // Just to be safe make sure the input marked as closed.
+                shutdownInput(true);
+            }
+        }
+
+        @Override
+        public KQueueRecvByteAllocatorHandle recvBufAllocHandle() {
+            if (allocHandle == null) {
+                allocHandle = new KQueueRecvByteAllocatorHandle(
+                        (RecvByteBufAllocator.ExtendedHandle) super.recvBufAllocHandle());
+            }
+            return allocHandle;
+        }
+
+        final void executeReadReadyRunnable(ChannelConfig config) {
+            if (readReadyRunnablePending || !isActive() || shouldBreakReadReady(config)) {
+                return;
+            }
+            readReadyRunnablePending = true;
+            eventLoop().execute(readReadyRunnable);
+        }
+
+        protected final void clearReadFilter0() {
+            assert eventLoop().inEventLoop();
+            try {
+                readPending = false;
+                readFilter(false);
+            } catch (IOException e) {
+                // When this happens there is something completely wrong with either the filedescriptor or epoll,
+                // so fire the exception through the pipeline and close the Channel.
+                pipeline().fireExceptionCaught(e);
+                unsafe().close(unsafe().voidPromise());
+            }
+        }
+
+        private void fireEventAndClose(Object evt) {
+            pipeline().fireUserEventTriggered(evt);
+            close(voidPromise());
+        }
+    }
+}

transport-native-kqueue/src/main/java/io/netty/channel/kqueue/AbstractKQueueServerChannel.java

@@ -0,0 +1,127 @@
+/*
+ * Copyright 2016 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache License,
+ * version 2.0 (the "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at:
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+package io.netty.channel.kqueue;
+
+import io.netty.channel.Channel;
+import io.netty.channel.ChannelConfig;
+import io.netty.channel.ChannelMetadata;
+import io.netty.channel.ChannelOutboundBuffer;
+import io.netty.channel.ChannelPipeline;
+import io.netty.channel.ChannelPromise;
+import io.netty.channel.EventLoop;
+import io.netty.channel.ServerChannel;
+import io.netty.util.internal.UnstableApi;
+
+import java.net.InetSocketAddress;
+import java.net.SocketAddress;
+
+@UnstableApi
+public abstract class AbstractKQueueServerChannel extends AbstractKQueueChannel implements ServerChannel {
+    private static final ChannelMetadata METADATA = new ChannelMetadata(false, 16);
+
+    AbstractKQueueServerChannel(BsdSocket fd, boolean active) {
+        super(null, fd, active);
+    }
+
+    @Override
+    public ChannelMetadata metadata() {
+        return METADATA;
+    }
+
+    @Override
+    protected boolean isCompatible(EventLoop loop) {
+        return loop instanceof KQueueEventLoop;
+    }
+
+    @Override
+    protected InetSocketAddress remoteAddress0() {
+        return null;
+    }
+
+    @Override
+    protected AbstractKQueueUnsafe newUnsafe() {
+        return new KQueueServerSocketUnsafe();
+    }
+
+    @Override
+    protected void doWrite(ChannelOutboundBuffer in) throws Exception {
+        throw new UnsupportedOperationException();
+    }
+
+    @Override
+    protected Object filterOutboundMessage(Object msg) throws Exception {
+        throw new UnsupportedOperationException();
+    }
+
+    abstract Channel newChildChannel(int fd, byte[] remote, int offset, int len) throws Exception;
+
+    final class KQueueServerSocketUnsafe extends AbstractKQueueUnsafe {
+        // Will hold the remote address after accept(...) was successful.
+        // We need 24 bytes for the address as maximum + 1 byte for storing the capacity.
+        // So use 26 bytes as it's a power of two.
+        private final byte[] acceptedAddress = new byte[26];
+
+        @Override
+        public void connect(SocketAddress socketAddress, SocketAddress socketAddress2, ChannelPromise channelPromise) {
+            // Connect not supported by ServerChannel implementations
+            channelPromise.setFailure(new UnsupportedOperationException());
+        }
+
+        @Override
+        void readReady(KQueueRecvByteAllocatorHandle allocHandle) {
+            assert eventLoop().inEventLoop();
+            final ChannelConfig config = config();
+            if (shouldBreakReadReady(config)) {
+                clearReadFilter0();
+                return;
+            }
+            final ChannelPipeline pipeline = pipeline();
+            allocHandle.reset(config);
+            allocHandle.attemptedBytesRead(1);
+            readReadyBefore();
+
+            Throwable exception = null;
+            try {
+                try {
+                    do {
+                        int acceptFd = socket.accept(acceptedAddress);
+                        if (acceptFd == -1) {
+                            // this means everything was handled for now
+                            allocHandle.lastBytesRead(-1);
+                            break;
+                        }
+                        allocHandle.lastBytesRead(1);
+                        allocHandle.incMessagesRead(1);
+
+                        readPending = false;
+                        pipeline.fireChannelRead(newChildChannel(acceptFd, acceptedAddress, 1,
+                                                                 acceptedAddress[0]));
+                    } while (allocHandle.continueReading());
+                } catch (Throwable t) {
+                    exception = t;
+                }
+                allocHandle.readComplete();
+                pipeline.fireChannelReadComplete();
+
+                if (exception != null) {
+                    pipeline.fireExceptionCaught(exception);
+                }
+            } finally {
+                readReadyFinally(config);
+            }
+        }
+    }
+}

transport-native-kqueue/src/main/java/io/netty/channel/kqueue/AbstractKQueueStreamChannel.java

@@ -0,0 +1,808 @@
+/*
+ * Copyright 2016 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache License,
+ * version 2.0 (the "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at:
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+package io.netty.channel.kqueue;
+
+import io.netty.buffer.ByteBuf;
+import io.netty.buffer.ByteBufAllocator;
+import io.netty.buffer.CompositeByteBuf;
+import io.netty.channel.Channel;
+import io.netty.channel.ChannelConfig;
+import io.netty.channel.ChannelFuture;
+import io.netty.channel.ChannelFutureListener;
+import io.netty.channel.ChannelMetadata;
+import io.netty.channel.ChannelOutboundBuffer;
+import io.netty.channel.ChannelPipeline;
+import io.netty.channel.ChannelPromise;
+import io.netty.channel.ConnectTimeoutException;
+import io.netty.channel.DefaultFileRegion;
+import io.netty.channel.EventLoop;
+import io.netty.channel.FileRegion;
+import io.netty.channel.socket.DuplexChannel;
+import io.netty.channel.unix.IovArray;
+import io.netty.channel.unix.SocketWritableByteChannel;
+import io.netty.util.internal.PlatformDependent;
+import io.netty.util.internal.StringUtil;
+import io.netty.util.internal.ThrowableUtil;
+import io.netty.util.internal.UnstableApi;
+
+import java.io.IOException;
+import java.net.SocketAddress;
+import java.nio.ByteBuffer;
+import java.nio.channels.ClosedChannelException;
+import java.nio.channels.ConnectionPendingException;
+import java.nio.channels.WritableByteChannel;
+import java.util.concurrent.Executor;
+import java.util.concurrent.ScheduledFuture;
+import java.util.concurrent.TimeUnit;
+
+import static io.netty.channel.unix.Limits.IOV_MAX;
+
+@UnstableApi
+public abstract class AbstractKQueueStreamChannel extends AbstractKQueueChannel implements DuplexChannel {
+    private static final ChannelMetadata METADATA = new ChannelMetadata(false, 16);
+    private static final ClosedChannelException DO_CLOSE_CLOSED_CHANNEL_EXCEPTION = ThrowableUtil.unknownStackTrace(
+            new ClosedChannelException(), AbstractKQueueStreamChannel.class, "doClose()");
+    private static final String EXPECTED_TYPES =
+            " (expected: " + StringUtil.simpleClassName(ByteBuf.class) + ", " +
+                    StringUtil.simpleClassName(DefaultFileRegion.class) + ')';
+
+    private ChannelPromise connectPromise;
+    private ScheduledFuture<?> connectTimeoutFuture;
+    private SocketAddress requestedRemoteAddress;
+    private WritableByteChannel byteChannel;
+
+    AbstractKQueueStreamChannel(Channel parent, BsdSocket fd, boolean active) {
+        super(parent, fd, active, true);
+    }
+
+    @Override
+    protected AbstractKQueueUnsafe newUnsafe() {
+        return new KQueueStreamUnsafe();
+    }
+
+    @Override
+    public ChannelMetadata metadata() {
+        return METADATA;
+    }
+
+    /**
+     * Write bytes form the given {@link ByteBuf} to the underlying {@link java.nio.channels.Channel}.
+     * @param buf           the {@link ByteBuf} from which the bytes should be written
+     */
+    private boolean writeBytes(ChannelOutboundBuffer in, ByteBuf buf, int writeSpinCount) throws Exception {
+        int readableBytes = buf.readableBytes();
+        if (readableBytes == 0) {
+            in.remove();
+            return true;
+        }
+
+        if (buf.hasMemoryAddress() || buf.nioBufferCount() == 1) {
+            int writtenBytes = doWriteBytes(buf, writeSpinCount);
+            in.removeBytes(writtenBytes);
+            return writtenBytes == readableBytes;
+        } else {
+            ByteBuffer[] nioBuffers = buf.nioBuffers();
+            return writeBytesMultiple(in, nioBuffers, nioBuffers.length, readableBytes, writeSpinCount);
+        }
+    }
+
+    private boolean writeBytesMultiple(
+            ChannelOutboundBuffer in, IovArray array, int writeSpinCount) throws IOException {
+
+        long expectedWrittenBytes = array.size();
+        final long initialExpectedWrittenBytes = expectedWrittenBytes;
+
+        int cnt = array.count();
+
+        assert expectedWrittenBytes != 0;
+        assert cnt != 0;
+
+        boolean done = false;
+        int offset = 0;
+        int end = offset + cnt;
+        for (int i = writeSpinCount; i > 0; --i) {
+            long localWrittenBytes = socket.writevAddresses(array.memoryAddress(offset), cnt);
+            if (localWrittenBytes == 0) {
+                break;
+            }
+            expectedWrittenBytes -= localWrittenBytes;
+
+            if (expectedWrittenBytes == 0) {
+                // Written everything, just break out here (fast-path)
+                done = true;
+                break;
+            }
+
+            do {
+                long bytes = array.processWritten(offset, localWrittenBytes);
+                if (bytes == -1) {
+                    // incomplete write
+                    break;
+                } else {
+                    offset++;
+                    cnt--;
+                    localWrittenBytes -= bytes;
+                }
+            } while (offset < end && localWrittenBytes > 0);
+        }
+        in.removeBytes(initialExpectedWrittenBytes - expectedWrittenBytes);
+        return done;
+    }
+
+    private boolean writeBytesMultiple(
+            ChannelOutboundBuffer in, ByteBuffer[] nioBuffers,
+            int nioBufferCnt, long expectedWrittenBytes, int writeSpinCount) throws IOException {
+
+        assert expectedWrittenBytes != 0;
+        final long initialExpectedWrittenBytes = expectedWrittenBytes;
+
+        boolean done = false;
+        int offset = 0;
+        int end = offset + nioBufferCnt;
+        for (int i = writeSpinCount; i > 0; --i) {
+            long localWrittenBytes = socket.writev(nioBuffers, offset, nioBufferCnt);
+            if (localWrittenBytes == 0) {
+                break;
+            }
+            expectedWrittenBytes -= localWrittenBytes;
+
+            if (expectedWrittenBytes == 0) {
+                // Written everything, just break out here (fast-path)
+                done = true;
+                break;
+            }
+            do {
+                ByteBuffer buffer = nioBuffers[offset];
+                int pos = buffer.position();
+                int bytes = buffer.limit() - pos;
+                if (bytes > localWrittenBytes) {
+                    buffer.position(pos + (int) localWrittenBytes);
+                    // incomplete write
+                    break;
+                } else {
+                    offset++;
+                    nioBufferCnt--;
+                    localWrittenBytes -= bytes;
+                }
+            } while (offset < end && localWrittenBytes > 0);
+        }
+
+        in.removeBytes(initialExpectedWrittenBytes - expectedWrittenBytes);
+        return done;
+    }
+
+    /**
+     * Write a {@link DefaultFileRegion}
+     *
+     * @param region        the {@link DefaultFileRegion} from which the bytes should be written
+     * @return amount       the amount of written bytes
+     */
+    private boolean writeDefaultFileRegion(
+            ChannelOutboundBuffer in, DefaultFileRegion region, int writeSpinCount) throws Exception {
+        final long regionCount = region.count();
+        if (region.transferred() >= regionCount) {
+            in.remove();
+            return true;
+        }
+
+        final long baseOffset = region.position();
+        boolean done = false;
+        long flushedAmount = 0;
+
+        for (int i = writeSpinCount; i > 0; --i) {
+            final long offset = region.transferred();
+            final long localFlushedAmount = socket.sendFile(region, baseOffset, offset, regionCount - offset);
+            if (localFlushedAmount == 0) {
+                break;
+            }
+
+            flushedAmount += localFlushedAmount;
+            if (region.transferred() >= regionCount) {
+                done = true;
+                break;
+            }
+        }
+
+        if (flushedAmount > 0) {
+            in.progress(flushedAmount);
+        }
+
+        if (done) {
+            in.remove();
+        }
+        return done;
+    }
+
+    private boolean writeFileRegion(
+            ChannelOutboundBuffer in, FileRegion region, final int writeSpinCount) throws Exception {
+        if (region.transferred() >= region.count()) {
+            in.remove();
+            return true;
+        }
+
+        boolean done = false;
+        long flushedAmount = 0;
+
+        if (byteChannel == null) {
+            byteChannel = new KQueueSocketWritableByteChannel();
+        }
+        for (int i = writeSpinCount; i > 0; --i) {
+            final long localFlushedAmount = region.transferTo(byteChannel, region.transferred());
+            if (localFlushedAmount == 0) {
+                break;
+            }
+
+            flushedAmount += localFlushedAmount;
+            if (region.transferred() >= region.count()) {
+                done = true;
+                break;
+            }
+        }
+
+        if (flushedAmount > 0) {
+            in.progress(flushedAmount);
+        }
+
+        if (done) {
+            in.remove();
+        }
+        return done;
+    }
+
+    @Override
+    protected void doWrite(ChannelOutboundBuffer in) throws Exception {
+        int writeSpinCount = config().getWriteSpinCount();
+        for (;;) {
+            final int msgCount = in.size();
+
+            if (msgCount == 0) {
+                // Wrote all messages.
+                writeFilter(false);
+                // Return here so we not set the EPOLLOUT flag.
+                return;
+            }
+
+            // Do gathering write if the outbounf buffer entries start with more than one ByteBuf.
+            if (msgCount > 1 && in.current() instanceof ByteBuf) {
+                if (!doWriteMultiple(in, writeSpinCount)) {
+                    // Break the loop and so set EPOLLOUT flag.
+                    break;
+                }
+
+                // We do not break the loop here even if the outbound buffer was flushed completely,
+                // because a user might have triggered another write and flush when we notify his or her
+                // listeners.
+            } else { // msgCount == 1
+                if (!doWriteSingle(in, writeSpinCount)) {
+                    // Break the loop and so set EPOLLOUT flag.
+                    break;
+                }
+            }
+        }
+        // Underlying descriptor can not accept all data currently, so set the EPOLLOUT flag to be woken up
+        // when it can accept more data.
+        writeFilter(true);
+    }
+
+    protected boolean doWriteSingle(ChannelOutboundBuffer in, int writeSpinCount) throws Exception {
+        // The outbound buffer contains only one message or it contains a file region.
+        Object msg = in.current();
+        if (msg instanceof ByteBuf) {
+            if (!writeBytes(in, (ByteBuf) msg, writeSpinCount)) {
+                // was not able to write everything so break here we will get notified later again once
+                // the network stack can handle more writes.
+                return false;
+            }
+        } else if (msg instanceof DefaultFileRegion) {
+            if (!writeDefaultFileRegion(in, (DefaultFileRegion) msg, writeSpinCount)) {
+                // was not able to write everything so break here we will get notified later again once
+                // the network stack can handle more writes.
+                return false;
+            }
+        } else if (msg instanceof FileRegion) {
+            if (!writeFileRegion(in, (FileRegion) msg, writeSpinCount)) {
+                // was not able to write everything so break here we will get notified later again once
+                // the network stack can handle more writes.
+                return false;
+            }
+        } else {
+            // Should never reach here.
+            throw new Error();
+        }
+
+        return true;
+    }
+
+    private boolean doWriteMultiple(ChannelOutboundBuffer in, int writeSpinCount) throws Exception {
+        if (PlatformDependent.hasUnsafe()) {
+            // this means we can cast to IovArray and write the IovArray directly.
+            IovArray array = ((KQueueEventLoop) eventLoop()).cleanArray();
+            in.forEachFlushedMessage(array);
+
+            int cnt = array.count();
+            if (cnt >= 1) {
+                // TODO: Handle the case where cnt == 1 specially.
+                if (!writeBytesMultiple(in, array, writeSpinCount)) {
+                    // was not able to write everything so break here we will get notified later again once
+                    // the network stack can handle more writes.
+                    return false;
+                }
+            } else { // cnt == 0, which means the outbound buffer contained empty buffers only.
+                in.removeBytes(0);
+            }
+        } else {
+            ByteBuffer[] buffers = in.nioBuffers();
+            int cnt = in.nioBufferCount();
+            if (cnt >= 1) {
+                // TODO: Handle the case where cnt == 1 specially.
+                if (!writeBytesMultiple(in, buffers, cnt, in.nioBufferSize(), writeSpinCount)) {
+                    // was not able to write everything so break here we will get notified later again once
+                    // the network stack can handle more writes.
+                    return false;
+                }
+            } else { // cnt == 0, which means the outbound buffer contained empty buffers only.
+                in.removeBytes(0);
+            }
+        }
+
+        return true;
+    }
+
+    @Override
+    protected Object filterOutboundMessage(Object msg) {
+        if (msg instanceof ByteBuf) {
+            ByteBuf buf = (ByteBuf) msg;
+            if (!buf.hasMemoryAddress() && (PlatformDependent.hasUnsafe() || !buf.isDirect())) {
+                if (buf instanceof CompositeByteBuf) {
+                    // Special handling of CompositeByteBuf to reduce memory copies if some of the Components
+                    // in the CompositeByteBuf are backed by a memoryAddress.
+                    CompositeByteBuf comp = (CompositeByteBuf) buf;
+                    if (!comp.isDirect() || comp.nioBufferCount() > IOV_MAX) {
+                        // more then 1024 buffers for gathering writes so just do a memory copy.
+                        buf = newDirectBuffer(buf);
+                        assert buf.hasMemoryAddress();
+                    }
+                } else {
+                    // We can only handle buffers with memory address so we need to copy if a non direct is
+                    // passed to write.
+                    buf = newDirectBuffer(buf);
+                    assert buf.hasMemoryAddress();
+                }
+            }
+            return buf;
+        }
+
+        if (msg instanceof FileRegion) {
+            return msg;
+        }
+
+        throw new UnsupportedOperationException(
+                "unsupported message type: " + StringUtil.simpleClassName(msg) + EXPECTED_TYPES);
+    }
+
+    private void shutdownOutput0(final ChannelPromise promise) {
+        try {
+            socket.shutdown(false, true);
+            promise.setSuccess();
+        } catch (Throwable cause) {
+            promise.setFailure(cause);
+        }
+    }
+
+    private void shutdownInput0(final ChannelPromise promise) {
+        try {
+            socket.shutdown(true, false);
+            promise.setSuccess();
+        } catch (Throwable cause) {
+            promise.setFailure(cause);
+        }
+    }
+
+    private void shutdown0(final ChannelPromise promise) {
+        try {
+            socket.shutdown(true, true);
+            promise.setSuccess();
+        } catch (Throwable cause) {
+            promise.setFailure(cause);
+        }
+    }
+
+    @Override
+    public boolean isOutputShutdown() {
+        return socket.isOutputShutdown();
+    }
+
+    @Override
+    public boolean isInputShutdown() {
+        return socket.isInputShutdown();
+    }
+
+    @Override
+    public boolean isShutdown() {
+        return socket.isShutdown();
+    }
+
+    @Override
+    public ChannelFuture shutdownOutput() {
+        return shutdownOutput(newPromise());
+    }
+
+    @Override
+    public ChannelFuture shutdownOutput(final ChannelPromise promise) {
+        Executor closeExecutor = ((KQueueStreamUnsafe) unsafe()).prepareToClose();
+        if (closeExecutor != null) {
+            closeExecutor.execute(new Runnable() {
+                @Override
+                public void run() {
+                    shutdownOutput0(promise);
+                }
+            });
+        } else {
+            EventLoop loop = eventLoop();
+            if (loop.inEventLoop()) {
+                shutdownOutput0(promise);
+            } else {
+                loop.execute(new Runnable() {
+                    @Override
+                    public void run() {
+                        shutdownOutput0(promise);
+                    }
+                });
+            }
+        }
+        return promise;
+    }
+
+    @Override
+    public ChannelFuture shutdownInput() {
+        return shutdownInput(newPromise());
+    }
+
+    @Override
+    public ChannelFuture shutdownInput(final ChannelPromise promise) {
+        Executor closeExecutor = ((KQueueStreamUnsafe) unsafe()).prepareToClose();
+        if (closeExecutor != null) {
+            closeExecutor.execute(new Runnable() {
+                @Override
+                public void run() {
+                    shutdownInput0(promise);
+                }
+            });
+        } else {
+            EventLoop loop = eventLoop();
+            if (loop.inEventLoop()) {
+                shutdownInput0(promise);
+            } else {
+                loop.execute(new Runnable() {
+                    @Override
+                    public void run() {
+                        shutdownInput0(promise);
+                    }
+                });
+            }
+        }
+        return promise;
+    }
+
+    @Override
+    public ChannelFuture shutdown() {
+        return shutdown(newPromise());
+    }
+
+    @Override
+    public ChannelFuture shutdown(final ChannelPromise promise) {
+        Executor closeExecutor = ((KQueueStreamUnsafe) unsafe()).prepareToClose();
+        if (closeExecutor != null) {
+            closeExecutor.execute(new Runnable() {
+                @Override
+                public void run() {
+                    shutdown0(promise);
+                }
+            });
+        } else {
+            EventLoop loop = eventLoop();
+            if (loop.inEventLoop()) {
+                shutdown0(promise);
+            } else {
+                loop.execute(new Runnable() {
+                    @Override
+                    public void run() {
+                        shutdown0(promise);
+                    }
+                });
+            }
+        }
+        return promise;
+    }
+
+    @Override
+    protected void doClose() throws Exception {
+        ChannelPromise promise = connectPromise;
+        if (promise != null) {
+            // Use tryFailure() instead of setFailure() to avoid the race against cancel().
+            promise.tryFailure(DO_CLOSE_CLOSED_CHANNEL_EXCEPTION);
+            connectPromise = null;
+        }
+
+        ScheduledFuture<?> future = connectTimeoutFuture;
+        if (future != null) {
+            future.cancel(false);
+            connectTimeoutFuture = null;
+        }
+        // Calling super.doClose() first so splceTo(...) will fail on next call.
+        super.doClose();
+    }
+
+    /**
+     * Connect to the remote peer
+     */
+    protected boolean doConnect(SocketAddress remoteAddress, SocketAddress localAddress) throws Exception {
+        if (localAddress != null) {
+            socket.bind(localAddress);
+        }
+
+        boolean success = false;
+        try {
+            boolean connected = socket.connect(remoteAddress);
+            if (!connected) {
+                writeFilter(true);
+            }
+            success = true;
+            return connected;
+        } finally {
+            if (!success) {
+                doClose();
+            }
+        }
+    }
+
+    class KQueueStreamUnsafe extends AbstractKQueueUnsafe {
+        // Overridden here just to be able to access this method from AbstractKQueueStreamChannel
+        @Override
+        protected Executor prepareToClose() {
+            return super.prepareToClose();
+        }
+
+        @Override
+        void readReady(final KQueueRecvByteAllocatorHandle allocHandle) {
+            final ChannelConfig config = config();
+            if (shouldBreakReadReady(config)) {
+                clearReadFilter0();
+                return;
+            }
+            final ChannelPipeline pipeline = pipeline();
+            final ByteBufAllocator allocator = config.getAllocator();
+            allocHandle.reset(config);
+            readReadyBefore();
+
+            ByteBuf byteBuf = null;
+            boolean close = false;
+            try {
+                do {
+                    // we use a direct buffer here as the native implementations only be able
+                    // to handle direct buffers.
+                    byteBuf = allocHandle.allocate(allocator);
+                    allocHandle.lastBytesRead(doReadBytes(byteBuf));
+                    if (allocHandle.lastBytesRead() <= 0) {
+                        // nothing was read, release the buffer.
+                        byteBuf.release();
+                        byteBuf = null;
+                        close = allocHandle.lastBytesRead() < 0;
+                        break;
+                    }
+                    allocHandle.incMessagesRead(1);
+                    readPending = false;
+                    pipeline.fireChannelRead(byteBuf);
+                    byteBuf = null;
+
+                    if (shouldBreakReadReady(config)) {
+                        // We need to do this for two reasons:
+                        //
+                        // - If the input was shutdown in between (which may be the case when the user did it in the
+                        //   fireChannelRead(...) method we should not try to read again to not produce any
+                        //   miss-leading exceptions.
+                        //
+                        // - If the user closes the channel we need to ensure we not try to read from it again as
+                        //   the filedescriptor may be re-used already by the OS if the system is handling a lot of
+                        //   concurrent connections and so needs a lot of filedescriptors. If not do this we risk
+                        //   reading data from a filedescriptor that belongs to another socket then the socket that
+                        //   was "wrapped" by this Channel implementation.
+                        break;
+                    }
+                } while (allocHandle.continueReading());
+
+                allocHandle.readComplete();
+                pipeline.fireChannelReadComplete();
+
+                if (close) {
+                    shutdownInput(false);
+                }
+            } catch (Throwable t) {
+                handleReadException(pipeline, byteBuf, t, close, allocHandle);
+            } finally {
+                readReadyFinally(config);
+            }
+        }
+
+        @Override
+        void writeReady() {
+            if (connectPromise != null) {
+                // pending connect which is now complete so handle it.
+                finishConnect();
+            } else {
+                super.writeReady();
+            }
+        }
+
+        @Override
+        public void connect(
+                final SocketAddress remoteAddress, final SocketAddress localAddress, final ChannelPromise promise) {
+            if (!promise.setUncancellable() || !ensureOpen(promise)) {
+                return;
+            }
+
+            try {
+                if (connectPromise != null) {
+                    throw new ConnectionPendingException();
+                }
+
+                boolean wasActive = isActive();
+                if (doConnect(remoteAddress, localAddress)) {
+                    fulfillConnectPromise(promise, wasActive);
+                } else {
+                    connectPromise = promise;
+                    requestedRemoteAddress = remoteAddress;
+
+                    // Schedule connect timeout.
+                    int connectTimeoutMillis = config().getConnectTimeoutMillis();
+                    if (connectTimeoutMillis > 0) {
+                        connectTimeoutFuture = eventLoop().schedule(new Runnable() {
+                            @Override
+                            public void run() {
+                                ChannelPromise connectPromise = AbstractKQueueStreamChannel.this.connectPromise;
+                                ConnectTimeoutException cause =
+                                        new ConnectTimeoutException("connection timed out: " + remoteAddress);
+                                if (connectPromise != null && connectPromise.tryFailure(cause)) {
+                                    close(voidPromise());
+                                }
+                            }
+                        }, connectTimeoutMillis, TimeUnit.MILLISECONDS);
+                    }
+
+                    promise.addListener(new ChannelFutureListener() {
+                        @Override
+                        public void operationComplete(ChannelFuture future) throws Exception {
+                            if (future.isCancelled()) {
+                                if (connectTimeoutFuture != null) {
+                                    connectTimeoutFuture.cancel(false);
+                                }
+                                connectPromise = null;
+                                close(voidPromise());
+                            }
+                        }
+                    });
+                }
+            } catch (Throwable t) {
+                closeIfClosed();
+                promise.tryFailure(annotateConnectException(t, remoteAddress));
+            }
+        }
+
+        private void fulfillConnectPromise(ChannelPromise promise, boolean wasActive) {
+            if (promise == null) {
+                // Closed via cancellation and the promise has been notified already.
+                return;
+            }
+            active = true;
+
+            // Get the state as trySuccess() may trigger an ChannelFutureListener that will close the Channel.
+            // We still need to ensure we call fireChannelActive() in this case.
+            boolean active = isActive();
+
+            // trySuccess() will return false if a user cancelled the connection attempt.
+            boolean promiseSet = promise.trySuccess();
+
+            // Regardless if the connection attempt was cancelled, channelActive() event should be triggered,
+            // because what happened is what happened.
+            if (!wasActive && active) {
+                pipeline().fireChannelActive();
+            }
+
+            // If a user cancelled the connection attempt, close the channel, which is followed by channelInactive().
+            if (!promiseSet) {
+                close(voidPromise());
+            }
+        }
+
+        private void fulfillConnectPromise(ChannelPromise promise, Throwable cause) {
+            if (promise == null) {
+                // Closed via cancellation and the promise has been notified already.
+                return;
+            }
+
+            // Use tryFailure() instead of setFailure() to avoid the race against cancel().
+            promise.tryFailure(cause);
+            closeIfClosed();
+        }
+
+        private void finishConnect() {
+            // Note this method is invoked by the event loop only if the connection attempt was
+            // neither cancelled nor timed out.
+
+            assert eventLoop().inEventLoop();
+
+            boolean connectStillInProgress = false;
+            try {
+                boolean wasActive = isActive();
+                if (!doFinishConnect()) {
+                    connectStillInProgress = true;
+                    return;
+                }
+                fulfillConnectPromise(connectPromise, wasActive);
+            } catch (Throwable t) {
+                fulfillConnectPromise(connectPromise, annotateConnectException(t, requestedRemoteAddress));
+            } finally {
+                if (!connectStillInProgress) {
+                    // Check for null as the connectTimeoutFuture is only created if a connectTimeoutMillis > 0 is used
+                    // See https://github.com/netty/netty/issues/1770
+                    if (connectTimeoutFuture != null) {
+                        connectTimeoutFuture.cancel(false);
+                    }
+                    connectPromise = null;
+                }
+            }
+        }
+
+        boolean doFinishConnect() throws Exception {
+            if (socket.finishConnect()) {
+                writeFilter(false);
+                return true;
+            } else {
+                writeFilter(true);
+                return false;
+            }
+        }
+
+        private void handleReadException(ChannelPipeline pipeline, ByteBuf byteBuf, Throwable cause, boolean close,
+                                         KQueueRecvByteAllocatorHandle allocHandle) {
+            if (byteBuf != null) {
+                if (byteBuf.isReadable()) {
+                    readPending = false;
+                    pipeline.fireChannelRead(byteBuf);
+                } else {
+                    byteBuf.release();
+                }
+            }
+            allocHandle.readComplete();
+            pipeline.fireChannelReadComplete();
+            pipeline.fireExceptionCaught(cause);
+            if (close || cause instanceof IOException) {
+                shutdownInput(false);
+            }
+        }
+    }
+
+    private final class KQueueSocketWritableByteChannel extends SocketWritableByteChannel {
+        KQueueSocketWritableByteChannel() {
+            super(socket);
+        }
+
+        @Override
+        protected ByteBufAllocator alloc() {
+            return AbstractKQueueStreamChannel.this.alloc();
+        }
+    }
+}

transport-native-kqueue/src/main/java/io/netty/channel/kqueue/AcceptFilter.java

@@ -0,0 +1,61 @@
+/*
+ * Copyright 2016 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache License,
+ * version 2.0 (the "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at:
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+package io.netty.channel.kqueue;
+
+import io.netty.util.internal.ObjectUtil;
+import io.netty.util.internal.UnstableApi;
+
+@UnstableApi
+public final class AcceptFilter {
+    static final AcceptFilter PLATFORM_UNSUPPORTED = new AcceptFilter("", "");
+    private final String filterName;
+    private final String filterArgs;
+
+    public AcceptFilter(String filterName, String filterArgs) {
+        this.filterName = ObjectUtil.checkNotNull(filterName, "filterName");
+        this.filterArgs = ObjectUtil.checkNotNull(filterArgs, "filterArgs");
+    }
+
+    public String filterName() {
+        return filterName;
+    }
+
+    public String filterArgs() {
+        return filterArgs;
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (o == this) {
+            return true;
+        }
+        if (!(o instanceof AcceptFilter)) {
+            return false;
+        }
+        AcceptFilter rhs = (AcceptFilter) o;
+        return filterName.equals(rhs.filterName) && filterArgs.equals(rhs.filterArgs);
+    }
+
+    @Override
+    public int hashCode() {
+        return 31 * (31 + filterName.hashCode()) + filterArgs.hashCode();
+    }
+
+    @Override
+    public String toString() {
+        return filterName + ", " + filterArgs;
+    }
+}

transport-native-kqueue/src/main/java/io/netty/channel/kqueue/BsdSocket.java

@@ -0,0 +1,119 @@
+/*
+ * Copyright 2016 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache License,
+ * version 2.0 (the "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at:
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+package io.netty.channel.kqueue;
+
+import io.netty.channel.DefaultFileRegion;
+import io.netty.channel.unix.Errors;
+import io.netty.channel.unix.PeerCredentials;
+import io.netty.channel.unix.Socket;
+import io.netty.util.internal.ThrowableUtil;
+
+import java.io.IOException;
+import java.nio.channels.ClosedChannelException;
+
+import static io.netty.channel.kqueue.AcceptFilter.PLATFORM_UNSUPPORTED;
+import static io.netty.channel.unix.Errors.ERRNO_EPIPE_NEGATIVE;
+import static io.netty.channel.unix.Errors.ioResult;
+import static io.netty.channel.unix.Errors.newConnectionResetException;
+
+/**
+ * A socket which provides access BSD native methods.
+ */
+final class BsdSocket extends Socket {
+    private static final Errors.NativeIoException SENDFILE_CONNECTION_RESET_EXCEPTION;
+    private static final ClosedChannelException SENDFILE_CLOSED_CHANNEL_EXCEPTION = ThrowableUtil.unknownStackTrace(
+            new ClosedChannelException(), Native.class, "sendfile(..)");
+
+    // These limits are just based on observations. I couldn't find anything in header files which formally
+    // define these limits.
+    private static final int APPLE_SND_LOW_AT_MAX = 1 << 17;
+    private static final int FREEBSD_SND_LOW_AT_MAX = 1 << 15;
+    static final int BSD_SND_LOW_AT_MAX = Math.min(APPLE_SND_LOW_AT_MAX, FREEBSD_SND_LOW_AT_MAX);
+
+    static {
+        SENDFILE_CONNECTION_RESET_EXCEPTION = newConnectionResetException("syscall:sendfile",
+                ERRNO_EPIPE_NEGATIVE);
+    }
+
+    BsdSocket(int fd) {
+        super(fd);
+    }
+
+    void setAcceptFilter(AcceptFilter acceptFilter) throws IOException {
+        setAcceptFilter(intValue(), acceptFilter.filterName(), acceptFilter.filterArgs());
+    }
+
+    void setTcpNoPush(boolean tcpNoPush) throws IOException {
+        setTcpNoPush(intValue(), tcpNoPush ? 1 : 0);
+    }
+
+    void setSndLowAt(int lowAt) throws IOException {
+        setSndLowAt(intValue(), lowAt);
+    }
+
+    boolean isTcpNoPush() throws IOException  {
+        return getTcpNoPush(intValue()) != 0;
+    }
+
+    int getSndLowAt() throws IOException {
+        return getSndLowAt(intValue());
+    }
+
+    AcceptFilter getAcceptFilter() throws IOException {
+        String[] result = getAcceptFilter(intValue());
+        return result == null ? PLATFORM_UNSUPPORTED : new AcceptFilter(result[0], result[1]);
+    }
+
+    PeerCredentials getPeerCredentials() throws IOException {
+        return getPeerCredentials(intValue());
+    }
+
+    long sendFile(DefaultFileRegion src, long baseOffset, long offset, long length) throws IOException {
+        // Open the file-region as it may be created via the lazy constructor. This is needed as we directly access
+        // the FileChannel field directly via JNI
+        src.open();
+
+        long res = sendFile(intValue(), src, baseOffset, offset, length);
+        if (res >= 0) {
+            return res;
+        }
+        return ioResult("sendfile", (int) res, SENDFILE_CONNECTION_RESET_EXCEPTION, SENDFILE_CLOSED_CHANNEL_EXCEPTION);
+    }
+
+    public static BsdSocket newSocketStream() {
+        return new BsdSocket(newSocketStream0());
+    }
+
+    public static BsdSocket newSocketDgram() {
+        return new BsdSocket(newSocketDgram0());
+    }
+
+    public static BsdSocket newSocketDomain() {
+        return new BsdSocket(newSocketDomain0());
+    }
+
+    private static native long sendFile(int socketFd, DefaultFileRegion src, long baseOffset,
+                                        long offset, long length) throws IOException;
+
+    private static native String[] getAcceptFilter(int fd) throws IOException;
+    private static native int getTcpNoPush(int fd) throws IOException;
+    private static native int getSndLowAt(int fd) throws IOException;
+    private static native PeerCredentials getPeerCredentials(int fd) throws IOException;
+
+    private static native void setAcceptFilter(int fd, String filterName, String filterArgs) throws IOException;
+    private static native void setTcpNoPush(int fd, int tcpNoPush) throws IOException;
+    private static native void setSndLowAt(int fd, int lowAt) throws IOException;
+}

transport-native-kqueue/src/main/java/io/netty/channel/kqueue/KQueue.java

@@ -0,0 +1,86 @@
+/*
+ * Copyright 2016 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache License,
+ * version 2.0 (the "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at:
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+package io.netty.channel.kqueue;
+
+import io.netty.channel.unix.FileDescriptor;
+import io.netty.util.internal.PlatformDependent;
+import io.netty.util.internal.UnstableApi;
+
+/**
+ * If KQueue is available the JNI resources will be loaded when this class loads.
+ */
+@UnstableApi
+public final class KQueue {
+    private static final Throwable UNAVAILABILITY_CAUSE;
+
+    static  {
+        Throwable cause = null;
+        FileDescriptor kqueueFd = null;
+        try {
+            kqueueFd = Native.newKQueue();
+        } catch (Throwable t) {
+            cause = t;
+        } finally {
+            if (kqueueFd != null) {
+                try {
+                    kqueueFd.close();
+                } catch (Exception ignore) {
+                    // ignore
+                }
+            }
+        }
+
+        if (cause != null) {
+            UNAVAILABILITY_CAUSE = cause;
+        } else {
+            UNAVAILABILITY_CAUSE = PlatformDependent.hasUnsafe() ? null :
+                    new IllegalStateException("sun.misc.Unsafe not available");
+        }
+    }
+
+    /**
+     * Returns {@code true} if and only if the
+     * <a href="http://netty.io/wiki/native-transports.html">{@code netty-transport-native-kqueue}</a> is available.
+     */
+    public static boolean isAvailable() {
+        return UNAVAILABILITY_CAUSE == null;
+    }
+
+    /**
+     * Ensure that <a href="http://netty.io/wiki/native-transports.html">{@code netty-transport-native-kqueue}</a> is
+     * available.
+     *
+     * @throws UnsatisfiedLinkError if unavailable
+     */
+    public static void ensureAvailability() {
+        if (UNAVAILABILITY_CAUSE != null) {
+            throw (Error) new UnsatisfiedLinkError(
+                    "failed to load the required native library").initCause(UNAVAILABILITY_CAUSE);
+        }
+    }
+
+    /**
+     * Returns the cause of unavailability of
+     * <a href="http://netty.io/wiki/native-transports.html">{@code netty-transport-native-kqueue}</a>.
+     *
+     * @return the cause if unavailable. {@code null} if available.
+     */
+    public static Throwable unavailabilityCause() {
+        return UNAVAILABILITY_CAUSE;
+    }
+
+    private KQueue() { }
+}

transport-native-kqueue/src/main/java/io/netty/channel/kqueue/KQueueChannelConfig.java

@@ -0,0 +1,156 @@
+/*
+ * Copyright 2016 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache License,
+ * version 2.0 (the "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at:
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+package io.netty.channel.kqueue;
+
+import io.netty.buffer.ByteBufAllocator;
+import io.netty.channel.ChannelOption;
+import io.netty.channel.DefaultChannelConfig;
+import io.netty.channel.MessageSizeEstimator;
+import io.netty.channel.RecvByteBufAllocator;
+import io.netty.channel.WriteBufferWaterMark;
+import io.netty.util.internal.UnstableApi;
+
+import java.util.Map;
+
+import static io.netty.channel.kqueue.KQueueChannelOption.RCV_ALLOC_TRANSPORT_PROVIDES_GUESS;
+
+@UnstableApi
+public class KQueueChannelConfig extends DefaultChannelConfig {
+    final AbstractKQueueChannel channel;
+    private volatile boolean transportProvidesGuess;
+
+    KQueueChannelConfig(AbstractKQueueChannel channel) {
+        super(channel);
+        this.channel = channel;
+    }
+
+    @Override
+    @SuppressWarnings("deprecation")
+    public Map<ChannelOption<?>, Object> getOptions() {
+        return getOptions(super.getOptions(), RCV_ALLOC_TRANSPORT_PROVIDES_GUESS);
+    }
+
+    @SuppressWarnings("unchecked")
+    @Override
+    public <T> T getOption(ChannelOption<T> option) {
+        if (option == RCV_ALLOC_TRANSPORT_PROVIDES_GUESS) {
+            return (T) Boolean.valueOf(getRcvAllocTransportProvidesGuess());
+        }
+        return super.getOption(option);
+    }
+
+    @Override
+    public <T> boolean setOption(ChannelOption<T> option, T value) {
+        validate(option, value);
+
+        if (option == RCV_ALLOC_TRANSPORT_PROVIDES_GUESS) {
+            setRcvAllocTransportProvidesGuess((Boolean) value);
+        } else {
+            return super.setOption(option, value);
+        }
+
+        return true;
+    }
+
+    /**
+     * If this is {@code true} then the {@link RecvByteBufAllocator.Handle#guess()} will be overriden to always attempt
+     * to read as many bytes as kqueue says are available.
+     */
+    public KQueueChannelConfig setRcvAllocTransportProvidesGuess(boolean transportProvidesGuess) {
+        this.transportProvidesGuess = transportProvidesGuess;
+        return this;
+    }
+
+    /**
+     * If this is {@code true} then the {@link RecvByteBufAllocator.Handle#guess()} will be overriden to always attempt
+     * to read as many bytes as kqueue says are available.
+     */
+    public boolean getRcvAllocTransportProvidesGuess() {
+        return transportProvidesGuess;
+    }
+
+    @Override
+    public KQueueChannelConfig setConnectTimeoutMillis(int connectTimeoutMillis) {
+        super.setConnectTimeoutMillis(connectTimeoutMillis);
+        return this;
+    }
+
+    @Override
+    @Deprecated
+    public KQueueChannelConfig setMaxMessagesPerRead(int maxMessagesPerRead) {
+        super.setMaxMessagesPerRead(maxMessagesPerRead);
+        return this;
+    }
+
+    @Override
+    public KQueueChannelConfig setWriteSpinCount(int writeSpinCount) {
+        super.setWriteSpinCount(writeSpinCount);
+        return this;
+    }
+
+    @Override
+    public KQueueChannelConfig setAllocator(ByteBufAllocator allocator) {
+        super.setAllocator(allocator);
+        return this;
+    }
+
+    @Override
+    public KQueueChannelConfig setRecvByteBufAllocator(RecvByteBufAllocator allocator) {
+        if (!(allocator.newHandle() instanceof RecvByteBufAllocator.ExtendedHandle)) {
+            throw new IllegalArgumentException("allocator.newHandle() must return an object of type: " +
+                    RecvByteBufAllocator.ExtendedHandle.class);
+        }
+        super.setRecvByteBufAllocator(allocator);
+        return this;
+    }
+
+    @Override
+    public KQueueChannelConfig setAutoRead(boolean autoRead) {
+        super.setAutoRead(autoRead);
+        return this;
+    }
+
+    @Override
+    @Deprecated
+    public KQueueChannelConfig setWriteBufferHighWaterMark(int writeBufferHighWaterMark) {
+        super.setWriteBufferHighWaterMark(writeBufferHighWaterMark);
+        return this;
+    }
+
+    @Override
+    @Deprecated
+    public KQueueChannelConfig setWriteBufferLowWaterMark(int writeBufferLowWaterMark) {
+        super.setWriteBufferLowWaterMark(writeBufferLowWaterMark);
+        return this;
+    }
+
+    @Override
+    public KQueueChannelConfig setWriteBufferWaterMark(WriteBufferWaterMark writeBufferWaterMark) {
+        super.setWriteBufferWaterMark(writeBufferWaterMark);
+        return this;
+    }
+
+    @Override
+    public KQueueChannelConfig setMessageSizeEstimator(MessageSizeEstimator estimator) {
+        super.setMessageSizeEstimator(estimator);
+        return this;
+    }
+
+    @Override
+    protected final void autoReadCleared() {
+        channel.clearReadFilter();
+    }
+}

transport-native-kqueue/src/main/java/io/netty/channel/kqueue/KQueueChannelOption.java

@@ -0,0 +1,39 @@
+/*
+ * Copyright 2016 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache License,
+ * version 2.0 (the "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at:
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+package io.netty.channel.kqueue;
+
+import io.netty.channel.ChannelOption;
+import io.netty.channel.RecvByteBufAllocator;
+import io.netty.channel.unix.UnixChannelOption;
+import io.netty.util.internal.UnstableApi;
+
+@UnstableApi
+public final class KQueueChannelOption<T> extends UnixChannelOption<T> {
+    public static final ChannelOption<Integer> SO_SNDLOWAT = valueOf(KQueueChannelOption.class, "SO_SNDLOWAT");
+    public static final ChannelOption<Boolean> TCP_NOPUSH = valueOf(KQueueChannelOption.class, "TCP_NOPUSH");
+    public static final ChannelOption<AcceptFilter> SO_ACCEPTFILTER =
+            valueOf(KQueueChannelOption.class, "SO_ACCEPTFILTER");
+    /**
+     * If this is {@code true} then the {@link RecvByteBufAllocator.Handle#guess()} will be overriden to always attempt
+     * to read as many bytes as kqueue says are available.
+     */
+    public static final ChannelOption<Boolean> RCV_ALLOC_TRANSPORT_PROVIDES_GUESS =
+            valueOf(KQueueChannelOption.class, "RCV_ALLOC_TRANSPORT_PROVIDES_GUESS");
+
+    @SuppressWarnings({ "unused", "deprecation" })
+    private KQueueChannelOption() {
+    }
+}

transport-native-kqueue/src/main/java/io/netty/channel/kqueue/KQueueDatagramChannel.java

@@ -0,0 +1,552 @@
+/*
+ * Copyright 2016 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache License,
+ * version 2.0 (the "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at:
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+package io.netty.channel.kqueue;
+
+import io.netty.buffer.ByteBuf;
+import io.netty.buffer.ByteBufAllocator;
+import io.netty.buffer.CompositeByteBuf;
+import io.netty.channel.AddressedEnvelope;
+import io.netty.channel.ChannelFuture;
+import io.netty.channel.ChannelMetadata;
+import io.netty.channel.ChannelOutboundBuffer;
+import io.netty.channel.ChannelPipeline;
+import io.netty.channel.ChannelPromise;
+import io.netty.channel.DefaultAddressedEnvelope;
+import io.netty.channel.socket.DatagramChannel;
+import io.netty.channel.socket.DatagramChannelConfig;
+import io.netty.channel.socket.DatagramPacket;
+import io.netty.channel.unix.DatagramSocketAddress;
+import io.netty.channel.unix.IovArray;
+import io.netty.util.internal.PlatformDependent;
+import io.netty.util.internal.StringUtil;
+import io.netty.util.internal.UnstableApi;
+
+import java.io.IOException;
+import java.net.InetAddress;
+import java.net.InetSocketAddress;
+import java.net.NetworkInterface;
+import java.net.SocketAddress;
+import java.net.SocketException;
+import java.nio.ByteBuffer;
+import java.nio.channels.NotYetConnectedException;
+import java.util.ArrayList;
+import java.util.List;
+
+import static io.netty.channel.kqueue.BsdSocket.newSocketDgram;
+import static io.netty.channel.unix.Limits.IOV_MAX;
+
+@UnstableApi
+public final class KQueueDatagramChannel extends AbstractKQueueChannel implements DatagramChannel {
+    private static final ChannelMetadata METADATA = new ChannelMetadata(true);
+    private static final String EXPECTED_TYPES =
+            " (expected: " + StringUtil.simpleClassName(DatagramPacket.class) + ", " +
+                    StringUtil.simpleClassName(AddressedEnvelope.class) + '<' +
+                    StringUtil.simpleClassName(ByteBuf.class) + ", " +
+                    StringUtil.simpleClassName(InetSocketAddress.class) + ">, " +
+                    StringUtil.simpleClassName(ByteBuf.class) + ')';
+
+    private volatile InetSocketAddress local;
+    private volatile InetSocketAddress remote;
+    private volatile boolean connected;
+    private final KQueueDatagramChannelConfig config;
+
+    public KQueueDatagramChannel() {
+        super(null, newSocketDgram(), false);
+        config = new KQueueDatagramChannelConfig(this);
+    }
+
+    KQueueDatagramChannel(BsdSocket socket, boolean active) {
+        super(null, socket, active);
+        config = new KQueueDatagramChannelConfig(this);
+        // As we create an EpollDatagramChannel from a FileDescriptor we should try to obtain the remote and local
+        // address from it. This is needed as the FileDescriptor may be bound already.
+        local = socket.localAddress();
+    }
+
+    @Override
+    public InetSocketAddress remoteAddress() {
+        return (InetSocketAddress) super.remoteAddress();
+    }
+
+    @Override
+    public InetSocketAddress localAddress() {
+        return (InetSocketAddress) super.localAddress();
+    }
+
+    @Override
+    public ChannelMetadata metadata() {
+        return METADATA;
+    }
+
+    @Override
+    @SuppressWarnings("deprecation")
+    public boolean isActive() {
+        return socket.isOpen() && (config.getActiveOnOpen() && isRegistered() || active);
+    }
+
+    @Override
+    public boolean isConnected() {
+        return connected;
+    }
+
+    @Override
+    public ChannelFuture joinGroup(InetAddress multicastAddress) {
+        return joinGroup(multicastAddress, newPromise());
+    }
+
+    @Override
+    public ChannelFuture joinGroup(InetAddress multicastAddress, ChannelPromise promise) {
+        try {
+            return joinGroup(
+                    multicastAddress,
+                    NetworkInterface.getByInetAddress(localAddress().getAddress()),
+                    null, promise);
+        } catch (SocketException e) {
+            promise.setFailure(e);
+        }
+        return promise;
+    }
+
+    @Override
+    public ChannelFuture joinGroup(
+            InetSocketAddress multicastAddress, NetworkInterface networkInterface) {
+        return joinGroup(multicastAddress, networkInterface, newPromise());
+    }
+
+    @Override
+    public ChannelFuture joinGroup(
+            InetSocketAddress multicastAddress, NetworkInterface networkInterface,
+            ChannelPromise promise) {
+        return joinGroup(multicastAddress.getAddress(), networkInterface, null, promise);
+    }
+
+    @Override
+    public ChannelFuture joinGroup(
+            InetAddress multicastAddress, NetworkInterface networkInterface, InetAddress source) {
+        return joinGroup(multicastAddress, networkInterface, source, newPromise());
+    }
+
+    @Override
+    public ChannelFuture joinGroup(
+            final InetAddress multicastAddress, final NetworkInterface networkInterface,
+            final InetAddress source, final ChannelPromise promise) {
+
+        if (multicastAddress == null) {
+            throw new NullPointerException("multicastAddress");
+        }
+
+        if (networkInterface == null) {
+            throw new NullPointerException("networkInterface");
+        }
+
+        promise.setFailure(new UnsupportedOperationException("Multicast not supported"));
+        return promise;
+    }
+
+    @Override
+    public ChannelFuture leaveGroup(InetAddress multicastAddress) {
+        return leaveGroup(multicastAddress, newPromise());
+    }
+
+    @Override
+    public ChannelFuture leaveGroup(InetAddress multicastAddress, ChannelPromise promise) {
+        try {
+            return leaveGroup(
+                    multicastAddress, NetworkInterface.getByInetAddress(localAddress().getAddress()), null, promise);
+        } catch (SocketException e) {
+            promise.setFailure(e);
+        }
+        return promise;
+    }
+
+    @Override
+    public ChannelFuture leaveGroup(
+            InetSocketAddress multicastAddress, NetworkInterface networkInterface) {
+        return leaveGroup(multicastAddress, networkInterface, newPromise());
+    }
+
+    @Override
+    public ChannelFuture leaveGroup(
+            InetSocketAddress multicastAddress,
+            NetworkInterface networkInterface, ChannelPromise promise) {
+        return leaveGroup(multicastAddress.getAddress(), networkInterface, null, promise);
+    }
+
+    @Override
+    public ChannelFuture leaveGroup(
+            InetAddress multicastAddress, NetworkInterface networkInterface, InetAddress source) {
+        return leaveGroup(multicastAddress, networkInterface, source, newPromise());
+    }
+
+    @Override
+    public ChannelFuture leaveGroup(
+            final InetAddress multicastAddress, final NetworkInterface networkInterface, final InetAddress source,
+            final ChannelPromise promise) {
+        if (multicastAddress == null) {
+            throw new NullPointerException("multicastAddress");
+        }
+        if (networkInterface == null) {
+            throw new NullPointerException("networkInterface");
+        }
+
+        promise.setFailure(new UnsupportedOperationException("Multicast not supported"));
+
+        return promise;
+    }
+
+    @Override
+    public ChannelFuture block(
+            InetAddress multicastAddress, NetworkInterface networkInterface,
+            InetAddress sourceToBlock) {
+        return block(multicastAddress, networkInterface, sourceToBlock, newPromise());
+    }
+
+    @Override
+    public ChannelFuture block(
+            final InetAddress multicastAddress, final NetworkInterface networkInterface,
+            final InetAddress sourceToBlock, final ChannelPromise promise) {
+        if (multicastAddress == null) {
+            throw new NullPointerException("multicastAddress");
+        }
+        if (sourceToBlock == null) {
+            throw new NullPointerException("sourceToBlock");
+        }
+
+        if (networkInterface == null) {
+            throw new NullPointerException("networkInterface");
+        }
+        promise.setFailure(new UnsupportedOperationException("Multicast not supported"));
+        return promise;
+    }
+
+    @Override
+    public ChannelFuture block(InetAddress multicastAddress, InetAddress sourceToBlock) {
+        return block(multicastAddress, sourceToBlock, newPromise());
+    }
+
+    @Override
+    public ChannelFuture block(
+            InetAddress multicastAddress, InetAddress sourceToBlock, ChannelPromise promise) {
+        try {
+            return block(
+                    multicastAddress,
+                    NetworkInterface.getByInetAddress(localAddress().getAddress()),
+                    sourceToBlock, promise);
+        } catch (Throwable e) {
+            promise.setFailure(e);
+        }
+        return promise;
+    }
+
+    @Override
+    protected AbstractKQueueUnsafe newUnsafe() {
+        return new KQueueDatagramChannelUnsafe();
+    }
+
+    @Override
+    protected InetSocketAddress localAddress0() {
+        return local;
+    }
+
+    @Override
+    protected InetSocketAddress remoteAddress0() {
+        return remote;
+    }
+
+    @Override
+    protected void doBind(SocketAddress localAddress) throws Exception {
+        InetSocketAddress addr = (InetSocketAddress) localAddress;
+        checkResolvable(addr);
+        socket.bind(addr);
+        local = socket.localAddress();
+        active = true;
+    }
+
+    @Override
+    protected void doWrite(ChannelOutboundBuffer in) throws Exception {
+        for (;;) {
+            Object msg = in.current();
+            if (msg == null) {
+                // Wrote all messages.
+                writeFilter(false);
+                break;
+            }
+
+            try {
+                boolean done = false;
+                for (int i = config().getWriteSpinCount(); i > 0; --i) {
+                    if (doWriteMessage(msg)) {
+                        done = true;
+                        break;
+                    }
+                }
+
+                if (done) {
+                    in.remove();
+                } else {
+                    // Did not write all messages.
+                    writeFilter(true);
+                    break;
+                }
+            } catch (IOException e) {
+                // Continue on write error as a DatagramChannel can write to multiple remote peers
+                //
+                // See https://github.com/netty/netty/issues/2665
+                in.remove(e);
+            }
+        }
+    }
+
+    private boolean doWriteMessage(Object msg) throws Exception {
+        final ByteBuf data;
+        InetSocketAddress remoteAddress;
+        if (msg instanceof AddressedEnvelope) {
+            @SuppressWarnings("unchecked")
+            AddressedEnvelope<ByteBuf, InetSocketAddress> envelope =
+                    (AddressedEnvelope<ByteBuf, InetSocketAddress>) msg;
+            data = envelope.content();
+            remoteAddress = envelope.recipient();
+        } else {
+            data = (ByteBuf) msg;
+            remoteAddress = null;
+        }
+
+        final int dataLen = data.readableBytes();
+        if (dataLen == 0) {
+            return true;
+        }
+
+        if (remoteAddress == null) {
+            remoteAddress = remote;
+            if (remoteAddress == null) {
+                throw new NotYetConnectedException();
+            }
+        }
+
+        final int writtenBytes;
+        if (data.hasMemoryAddress()) {
+            long memoryAddress = data.memoryAddress();
+            writtenBytes = socket.sendToAddress(memoryAddress, data.readerIndex(), data.writerIndex(),
+                    remoteAddress.getAddress(), remoteAddress.getPort());
+        } else if (data instanceof CompositeByteBuf) {
+            IovArray array = ((KQueueEventLoop) eventLoop()).cleanArray();
+            array.add(data);
+            int cnt = array.count();
+            assert cnt != 0;
+
+            writtenBytes = socket.sendToAddresses(array.memoryAddress(0),
+                    cnt, remoteAddress.getAddress(), remoteAddress.getPort());
+        } else  {
+            ByteBuffer nioData = data.internalNioBuffer(data.readerIndex(), data.readableBytes());
+            writtenBytes = socket.sendTo(nioData, nioData.position(), nioData.limit(),
+                    remoteAddress.getAddress(), remoteAddress.getPort());
+        }
+
+        return writtenBytes > 0;
+    }
+
+    @Override
+    protected Object filterOutboundMessage(Object msg) {
+        if (msg instanceof DatagramPacket) {
+            DatagramPacket packet = (DatagramPacket) msg;
+            ByteBuf content = packet.content();
+            if (content.hasMemoryAddress()) {
+                return msg;
+            }
+
+            if (content.isDirect() && content instanceof CompositeByteBuf) {
+                // Special handling of CompositeByteBuf to reduce memory copies if some of the Components
+                // in the CompositeByteBuf are backed by a memoryAddress.
+                CompositeByteBuf comp = (CompositeByteBuf) content;
+                if (comp.isDirect() && comp.nioBufferCount() <= IOV_MAX) {
+                    return msg;
+                }
+            }
+            // We can only handle direct buffers so we need to copy if a non direct is
+            // passed to write.
+            return new DatagramPacket(newDirectBuffer(packet, content), packet.recipient());
+        }
+
+        if (msg instanceof ByteBuf) {
+            ByteBuf buf = (ByteBuf) msg;
+            if (!buf.hasMemoryAddress() && (PlatformDependent.hasUnsafe() || !buf.isDirect())) {
+                if (buf instanceof CompositeByteBuf) {
+                    // Special handling of CompositeByteBuf to reduce memory copies if some of the Components
+                    // in the CompositeByteBuf are backed by a memoryAddress.
+                    CompositeByteBuf comp = (CompositeByteBuf) buf;
+                    if (!comp.isDirect() || comp.nioBufferCount() > IOV_MAX) {
+                        // more then 1024 buffers for gathering writes so just do a memory copy.
+                        buf = newDirectBuffer(buf);
+                        assert buf.hasMemoryAddress();
+                    }
+                } else {
+                    // We can only handle buffers with memory address so we need to copy if a non direct is
+                    // passed to write.
+                    buf = newDirectBuffer(buf);
+                    assert buf.hasMemoryAddress();
+                }
+            }
+            return buf;
+        }
+
+        if (msg instanceof AddressedEnvelope) {
+            @SuppressWarnings("unchecked")
+            AddressedEnvelope<Object, SocketAddress> e = (AddressedEnvelope<Object, SocketAddress>) msg;
+            if (e.content() instanceof ByteBuf &&
+                    (e.recipient() == null || e.recipient() instanceof InetSocketAddress)) {
+
+                ByteBuf content = (ByteBuf) e.content();
+                if (content.hasMemoryAddress()) {
+                    return e;
+                }
+                if (content instanceof CompositeByteBuf) {
+                    // Special handling of CompositeByteBuf to reduce memory copies if some of the Components
+                    // in the CompositeByteBuf are backed by a memoryAddress.
+                    CompositeByteBuf comp = (CompositeByteBuf) content;
+                    if (comp.isDirect() && comp.nioBufferCount() <= IOV_MAX) {
+                        return e;
+                    }
+                }
+                // We can only handle direct buffers so we need to copy if a non direct is
+                // passed to write.
+                return new DefaultAddressedEnvelope<ByteBuf, InetSocketAddress>(
+                        newDirectBuffer(e, content), (InetSocketAddress) e.recipient());
+            }
+        }
+
+        throw new UnsupportedOperationException(
+                "unsupported message type: " + StringUtil.simpleClassName(msg) + EXPECTED_TYPES);
+    }
+
+    @Override
+    public KQueueDatagramChannelConfig config() {
+        return config;
+    }
+
+    @Override
+    protected void doDisconnect() throws Exception {
+        connected = false;
+    }
+
+    final class KQueueDatagramChannelUnsafe extends AbstractKQueueUnsafe {
+        private final List<Object> readBuf = new ArrayList<Object>();
+
+        @Override
+        public void connect(SocketAddress remote, SocketAddress local, ChannelPromise channelPromise) {
+            boolean success = false;
+            try {
+                try {
+                    boolean wasActive = isActive();
+                    InetSocketAddress remoteAddress = (InetSocketAddress) remote;
+                    if (local != null) {
+                        InetSocketAddress localAddress = (InetSocketAddress) local;
+                        doBind(localAddress);
+                    }
+
+                    checkResolvable(remoteAddress);
+                    KQueueDatagramChannel.this.remote = remoteAddress;
+                    KQueueDatagramChannel.this.local = socket.localAddress();
+                    success = true;
+
+                    // First notify the promise before notifying the handler.
+                    channelPromise.trySuccess();
+
+                    // Regardless if the connection attempt was cancelled, channelActive() event should be triggered,
+                    // because what happened is what happened.
+                    if (!wasActive && isActive()) {
+                        pipeline().fireChannelActive();
+                    }
+                } finally {
+                    if (!success) {
+                        doClose();
+                    } else {
+                        connected = true;
+                    }
+                }
+            } catch (Throwable cause) {
+                channelPromise.tryFailure(cause);
+            }
+        }
+
+        @Override
+        void readReady(KQueueRecvByteAllocatorHandle allocHandle) {
+            assert eventLoop().inEventLoop();
+            final DatagramChannelConfig config = config();
+            if (shouldBreakReadReady(config)) {
+                clearReadFilter0();
+                return;
+            }
+            final ChannelPipeline pipeline = pipeline();
+            final ByteBufAllocator allocator = config.getAllocator();
+            allocHandle.reset(config);
+            readReadyBefore();
+
+            Throwable exception = null;
+            try {
+                ByteBuf data = null;
+                try {
+                    do {
+                        data = allocHandle.allocate(allocator);
+                        allocHandle.attemptedBytesRead(data.writableBytes());
+                        final DatagramSocketAddress remoteAddress;
+                        if (data.hasMemoryAddress()) {
+                            // has a memory address so use optimized call
+                            remoteAddress = socket.recvFromAddress(data.memoryAddress(), data.writerIndex(),
+                                    data.capacity());
+                        } else {
+                            ByteBuffer nioData = data.internalNioBuffer(data.writerIndex(), data.writableBytes());
+                            remoteAddress = socket.recvFrom(nioData, nioData.position(), nioData.limit());
+                        }
+
+                        if (remoteAddress == null) {
+                            allocHandle.lastBytesRead(-1);
+                            data.release();
+                            data = null;
+                            break;
+                        }
+
+                        allocHandle.incMessagesRead(1);
+                        allocHandle.lastBytesRead(remoteAddress.receivedAmount());
+                        data.writerIndex(data.writerIndex() + allocHandle.lastBytesRead());
+
+                        readBuf.add(new DatagramPacket(data, (InetSocketAddress) localAddress(), remoteAddress));
+                        data = null;
+                    } while (allocHandle.continueReading());
+                } catch (Throwable t) {
+                    if (data != null) {
+                        data.release();
+                    }
+                    exception = t;
+                }
+
+                int size = readBuf.size();
+                for (int i = 0; i < size; i ++) {
+                    readPending = false;
+                    pipeline.fireChannelRead(readBuf.get(i));
+                }
+                readBuf.clear();
+                allocHandle.readComplete();
+                pipeline.fireChannelReadComplete();
+
+                if (exception != null) {
+                    pipeline.fireExceptionCaught(exception);
+                }
+            } finally {
+                readReadyFinally(config);
+            }
+        }
+    }
+}

transport-native-kqueue/src/main/java/io/netty/channel/kqueue/KQueueDatagramChannelConfig.java

@@ -0,0 +1,387 @@
+/*
+ * Copyright 2016 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache License,
+ * version 2.0 (the "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at:
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+package io.netty.channel.kqueue;
+
+import io.netty.buffer.ByteBufAllocator;
+import io.netty.channel.ChannelException;
+import io.netty.channel.ChannelOption;
+import io.netty.channel.FixedRecvByteBufAllocator;
+import io.netty.channel.MessageSizeEstimator;
+import io.netty.channel.RecvByteBufAllocator;
+import io.netty.channel.WriteBufferWaterMark;
+import io.netty.channel.socket.DatagramChannelConfig;
+import io.netty.util.internal.UnstableApi;
+
+import java.io.IOException;
+import java.net.InetAddress;
+import java.net.NetworkInterface;
+import java.util.Map;
+
+import static io.netty.channel.ChannelOption.DATAGRAM_CHANNEL_ACTIVE_ON_REGISTRATION;
+import static io.netty.channel.ChannelOption.IP_MULTICAST_ADDR;
+import static io.netty.channel.ChannelOption.IP_MULTICAST_IF;
+import static io.netty.channel.ChannelOption.IP_MULTICAST_LOOP_DISABLED;
+import static io.netty.channel.ChannelOption.IP_MULTICAST_TTL;
+import static io.netty.channel.ChannelOption.IP_TOS;
+import static io.netty.channel.ChannelOption.SO_BROADCAST;
+import static io.netty.channel.ChannelOption.SO_RCVBUF;
+import static io.netty.channel.ChannelOption.SO_REUSEADDR;
+import static io.netty.channel.ChannelOption.SO_SNDBUF;
+import static io.netty.channel.unix.UnixChannelOption.SO_REUSEPORT;
+
+@UnstableApi
+public final class KQueueDatagramChannelConfig extends KQueueChannelConfig implements DatagramChannelConfig {
+    private static final RecvByteBufAllocator DEFAULT_RCVBUF_ALLOCATOR = new FixedRecvByteBufAllocator(2048);
+    private final KQueueDatagramChannel datagramChannel;
+    private boolean activeOnOpen;
+
+    KQueueDatagramChannelConfig(KQueueDatagramChannel channel) {
+        super(channel);
+        this.datagramChannel = channel;
+        setRecvByteBufAllocator(DEFAULT_RCVBUF_ALLOCATOR);
+    }
+
+    @Override
+    @SuppressWarnings("deprecation")
+    public Map<ChannelOption<?>, Object> getOptions() {
+        return getOptions(
+                super.getOptions(),
+                SO_BROADCAST, SO_RCVBUF, SO_SNDBUF, SO_REUSEADDR, IP_MULTICAST_LOOP_DISABLED,
+                IP_MULTICAST_ADDR, IP_MULTICAST_IF, IP_MULTICAST_TTL,
+                IP_TOS, DATAGRAM_CHANNEL_ACTIVE_ON_REGISTRATION, SO_REUSEPORT);
+    }
+
+    @SuppressWarnings({ "unchecked", "deprecation" })
+    @Override
+    public <T> T getOption(ChannelOption<T> option) {
+        if (option == SO_BROADCAST) {
+            return (T) Boolean.valueOf(isBroadcast());
+        }
+        if (option == SO_RCVBUF) {
+            return (T) Integer.valueOf(getReceiveBufferSize());
+        }
+        if (option == SO_SNDBUF) {
+            return (T) Integer.valueOf(getSendBufferSize());
+        }
+        if (option == SO_REUSEADDR) {
+            return (T) Boolean.valueOf(isReuseAddress());
+        }
+        if (option == IP_MULTICAST_LOOP_DISABLED) {
+            return (T) Boolean.valueOf(isLoopbackModeDisabled());
+        }
+        if (option == IP_MULTICAST_ADDR) {
+            return (T) getInterface();
+        }
+        if (option == IP_MULTICAST_IF) {
+            return (T) getNetworkInterface();
+        }
+        if (option == IP_MULTICAST_TTL) {
+            return (T) Integer.valueOf(getTimeToLive());
+        }
+        if (option == IP_TOS) {
+            return (T) Integer.valueOf(getTrafficClass());
+        }
+        if (option == DATAGRAM_CHANNEL_ACTIVE_ON_REGISTRATION) {
+            return (T) Boolean.valueOf(activeOnOpen);
+        }
+        if (option == SO_REUSEPORT) {
+            return (T) Boolean.valueOf(isReusePort());
+        }
+        return super.getOption(option);
+    }
+
+    @Override
+    @SuppressWarnings("deprecation")
+    public <T> boolean setOption(ChannelOption<T> option, T value) {
+        validate(option, value);
+
+        if (option == SO_BROADCAST) {
+            setBroadcast((Boolean) value);
+        } else if (option == SO_RCVBUF) {
+            setReceiveBufferSize((Integer) value);
+        } else if (option == SO_SNDBUF) {
+            setSendBufferSize((Integer) value);
+        } else if (option == SO_REUSEADDR) {
+            setReuseAddress((Boolean) value);
+        } else if (option == IP_MULTICAST_LOOP_DISABLED) {
+            setLoopbackModeDisabled((Boolean) value);
+        } else if (option == IP_MULTICAST_ADDR) {
+            setInterface((InetAddress) value);
+        } else if (option == IP_MULTICAST_IF) {
+            setNetworkInterface((NetworkInterface) value);
+        } else if (option == IP_MULTICAST_TTL) {
+            setTimeToLive((Integer) value);
+        } else if (option == IP_TOS) {
+            setTrafficClass((Integer) value);
+        } else if (option == DATAGRAM_CHANNEL_ACTIVE_ON_REGISTRATION) {
+            setActiveOnOpen((Boolean) value);
+        } else if (option == SO_REUSEPORT) {
+            setReusePort((Boolean) value);
+        } else {
+            return super.setOption(option, value);
+        }
+
+        return true;
+    }
+
+    private void setActiveOnOpen(boolean activeOnOpen) {
+        if (channel.isRegistered()) {
+            throw new IllegalStateException("Can only changed before channel was registered");
+        }
+        this.activeOnOpen = activeOnOpen;
+    }
+
+    boolean getActiveOnOpen() {
+        return activeOnOpen;
+    }
+
+    /**
+     * Returns {@code true} if the SO_REUSEPORT option is set.
+     */
+    public boolean isReusePort() {
+        try {
+            return datagramChannel.socket.isReusePort();
+        } catch (IOException e) {
+            throw new ChannelException(e);
+        }
+    }
+
+    /**
+     * Set the SO_REUSEPORT option on the underlying Channel. This will allow to bind multiple
+     * {@link KQueueSocketChannel}s to the same port and so accept connections with multiple threads.
+     *
+     * Be aware this method needs be called before {@link KQueueDatagramChannel#bind(java.net.SocketAddress)} to have
+     * any affect.
+     */
+    public KQueueDatagramChannelConfig setReusePort(boolean reusePort) {
+        try {
+            datagramChannel.socket.setReusePort(reusePort);
+            return this;
+        } catch (IOException e) {
+            throw new ChannelException(e);
+        }
+    }
+
+    @Override
+    public KQueueDatagramChannelConfig setRcvAllocTransportProvidesGuess(boolean transportProvidesGuess) {
+        super.setRcvAllocTransportProvidesGuess(transportProvidesGuess);
+        return this;
+    }
+
+    @Override
+    public KQueueDatagramChannelConfig setMessageSizeEstimator(MessageSizeEstimator estimator) {
+        super.setMessageSizeEstimator(estimator);
+        return this;
+    }
+
+    @Override
+    @Deprecated
+    public KQueueDatagramChannelConfig setWriteBufferLowWaterMark(int writeBufferLowWaterMark) {
+        super.setWriteBufferLowWaterMark(writeBufferLowWaterMark);
+        return this;
+    }
+
+    @Override
+    @Deprecated
+    public KQueueDatagramChannelConfig setWriteBufferHighWaterMark(int writeBufferHighWaterMark) {
+        super.setWriteBufferHighWaterMark(writeBufferHighWaterMark);
+        return this;
+    }
+
+    @Override
+    public KQueueDatagramChannelConfig setWriteBufferWaterMark(WriteBufferWaterMark writeBufferWaterMark) {
+        super.setWriteBufferWaterMark(writeBufferWaterMark);
+        return this;
+    }
+
+    @Override
+    public KQueueDatagramChannelConfig setAutoClose(boolean autoClose) {
+        super.setAutoClose(autoClose);
+        return this;
+    }
+
+    @Override
+    public KQueueDatagramChannelConfig setAutoRead(boolean autoRead) {
+        super.setAutoRead(autoRead);
+        return this;
+    }
+
+    @Override
+    public KQueueDatagramChannelConfig setRecvByteBufAllocator(RecvByteBufAllocator allocator) {
+        super.setRecvByteBufAllocator(allocator);
+        return this;
+    }
+
+    @Override
+    public KQueueDatagramChannelConfig setWriteSpinCount(int writeSpinCount) {
+        super.setWriteSpinCount(writeSpinCount);
+        return this;
+    }
+
+    @Override
+    public KQueueDatagramChannelConfig setAllocator(ByteBufAllocator allocator) {
+        super.setAllocator(allocator);
+        return this;
+    }
+
+    @Override
+    public KQueueDatagramChannelConfig setConnectTimeoutMillis(int connectTimeoutMillis) {
+        super.setConnectTimeoutMillis(connectTimeoutMillis);
+        return this;
+    }
+
+    @Override
+    @Deprecated
+    public KQueueDatagramChannelConfig setMaxMessagesPerRead(int maxMessagesPerRead) {
+        super.setMaxMessagesPerRead(maxMessagesPerRead);
+        return this;
+    }
+
+    @Override
+    public int getSendBufferSize() {
+        try {
+            return datagramChannel.socket.getSendBufferSize();
+        } catch (IOException e) {
+            throw new ChannelException(e);
+        }
+    }
+
+    @Override
+    public KQueueDatagramChannelConfig setSendBufferSize(int sendBufferSize) {
+        try {
+            datagramChannel.socket.setSendBufferSize(sendBufferSize);
+            return this;
+        } catch (IOException e) {
+            throw new ChannelException(e);
+        }
+    }
+
+    @Override
+    public int getReceiveBufferSize() {
+        try {
+            return datagramChannel.socket.getReceiveBufferSize();
+        } catch (IOException e) {
+            throw new ChannelException(e);
+        }
+    }
+
+    @Override
+    public KQueueDatagramChannelConfig setReceiveBufferSize(int receiveBufferSize) {
+        try {
+            datagramChannel.socket.setReceiveBufferSize(receiveBufferSize);
+            return this;
+        } catch (IOException e) {
+            throw new ChannelException(e);
+        }
+    }
+
+    @Override
+    public int getTrafficClass() {
+        try {
+            return datagramChannel.socket.getTrafficClass();
+        } catch (IOException e) {
+            throw new ChannelException(e);
+        }
+    }
+
+    @Override
+    public KQueueDatagramChannelConfig setTrafficClass(int trafficClass) {
+        try {
+            datagramChannel.socket.setTrafficClass(trafficClass);
+            return this;
+        } catch (IOException e) {
+            throw new ChannelException(e);
+        }
+    }
+
+    @Override
+    public boolean isReuseAddress() {
+        try {
+            return datagramChannel.socket.isReuseAddress();
+        } catch (IOException e) {
+            throw new ChannelException(e);
+        }
+    }
+
+    @Override
+    public KQueueDatagramChannelConfig setReuseAddress(boolean reuseAddress) {
+        try {
+            datagramChannel.socket.setReuseAddress(reuseAddress);
+            return this;
+        } catch (IOException e) {
+            throw new ChannelException(e);
+        }
+    }
+
+    @Override
+    public boolean isBroadcast() {
+        try {
+            return datagramChannel.socket.isBroadcast();
+        } catch (IOException e) {
+            throw new ChannelException(e);
+        }
+    }
+
+    @Override
+    public KQueueDatagramChannelConfig setBroadcast(boolean broadcast) {
+        try {
+            datagramChannel.socket.setBroadcast(broadcast);
+            return this;
+        } catch (IOException e) {
+            throw new ChannelException(e);
+        }
+    }
+
+    @Override
+    public boolean isLoopbackModeDisabled() {
+        return false;
+    }
+
+    @Override
+    public DatagramChannelConfig setLoopbackModeDisabled(boolean loopbackModeDisabled) {
+        throw new UnsupportedOperationException("Multicast not supported");
+    }
+
+    @Override
+    public int getTimeToLive() {
+        return -1;
+    }
+
+    @Override
+    public KQueueDatagramChannelConfig setTimeToLive(int ttl) {
+        throw new UnsupportedOperationException("Multicast not supported");
+    }
+
+    @Override
+    public InetAddress getInterface() {
+        return null;
+    }
+
+    @Override
+    public KQueueDatagramChannelConfig setInterface(InetAddress interfaceAddress) {
+        throw new UnsupportedOperationException("Multicast not supported");
+    }
+
+    @Override
+    public NetworkInterface getNetworkInterface() {
+        return null;
+    }
+
+    @Override
+    public KQueueDatagramChannelConfig setNetworkInterface(NetworkInterface networkInterface) {
+        throw new UnsupportedOperationException("Multicast not supported");
+    }
+}

transport-native-kqueue/src/main/java/io/netty/channel/kqueue/KQueueDomainSocketChannel.java

@@ -0,0 +1,183 @@
+/*
+ * Copyright 2016 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache License,
+ * version 2.0 (the "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at:
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+package io.netty.channel.kqueue;
+
+import io.netty.channel.Channel;
+import io.netty.channel.ChannelConfig;
+import io.netty.channel.ChannelOutboundBuffer;
+import io.netty.channel.ChannelPipeline;
+import io.netty.channel.unix.DomainSocketAddress;
+import io.netty.channel.unix.DomainSocketChannel;
+import io.netty.channel.unix.FileDescriptor;
+import io.netty.channel.unix.PeerCredentials;
+import io.netty.util.internal.UnstableApi;
+
+import java.io.IOException;
+import java.net.SocketAddress;
+
+import static io.netty.channel.kqueue.BsdSocket.newSocketDomain;
+
+@UnstableApi
+public final class KQueueDomainSocketChannel extends AbstractKQueueStreamChannel implements DomainSocketChannel {
+    private final KQueueDomainSocketChannelConfig config = new KQueueDomainSocketChannelConfig(this);
+
+    private volatile DomainSocketAddress local;
+    private volatile DomainSocketAddress remote;
+
+    public KQueueDomainSocketChannel() {
+        super(null, newSocketDomain(), false);
+    }
+
+    KQueueDomainSocketChannel(Channel parent, BsdSocket fd) {
+        super(parent, fd, true);
+    }
+
+    @Override
+    protected AbstractKQueueUnsafe newUnsafe() {
+        return new KQueueDomainUnsafe();
+    }
+
+    @Override
+    protected DomainSocketAddress localAddress0() {
+        return local;
+    }
+
+    @Override
+    protected DomainSocketAddress remoteAddress0() {
+        return remote;
+    }
+
+    @Override
+    protected void doBind(SocketAddress localAddress) throws Exception {
+        socket.bind(localAddress);
+        local = (DomainSocketAddress) localAddress;
+    }
+
+    @Override
+    public KQueueDomainSocketChannelConfig config() {
+        return config;
+    }
+
+    @Override
+    protected boolean doConnect(SocketAddress remoteAddress, SocketAddress localAddress) throws Exception {
+        if (super.doConnect(remoteAddress, localAddress)) {
+            local = (DomainSocketAddress) localAddress;
+            remote = (DomainSocketAddress) remoteAddress;
+            return true;
+        }
+        return false;
+    }
+
+    @Override
+    public DomainSocketAddress remoteAddress() {
+        return (DomainSocketAddress) super.remoteAddress();
+    }
+
+    @Override
+    public DomainSocketAddress localAddress() {
+        return (DomainSocketAddress) super.localAddress();
+    }
+
+    @Override
+    protected boolean doWriteSingle(ChannelOutboundBuffer in, int writeSpinCount) throws Exception {
+        Object msg = in.current();
+        if (msg instanceof FileDescriptor && socket.sendFd(((FileDescriptor) msg).intValue()) > 0) {
+            // File descriptor was written, so remove it.
+            in.remove();
+            return true;
+        }
+        return super.doWriteSingle(in, writeSpinCount);
+    }
+
+    @Override
+    protected Object filterOutboundMessage(Object msg) {
+        if (msg instanceof FileDescriptor) {
+            return msg;
+        }
+        return super.filterOutboundMessage(msg);
+    }
+
+    /**
+     * Returns the unix credentials (uid, gid, pid) of the peer
+     * <a href=http://man7.org/linux/man-pages/man7/socket.7.html>SO_PEERCRED</a>
+     */
+    @UnstableApi
+    public PeerCredentials peerCredentials() throws IOException {
+        return socket.getPeerCredentials();
+    }
+
+    private final class KQueueDomainUnsafe extends KQueueStreamUnsafe {
+        @Override
+        void readReady(KQueueRecvByteAllocatorHandle allocHandle) {
+            switch (config().getReadMode()) {
+                case BYTES:
+                    super.readReady(allocHandle);
+                    break;
+                case FILE_DESCRIPTORS:
+                    readReadyFd();
+                    break;
+                default:
+                    throw new Error();
+            }
+        }
+
+        private void readReadyFd() {
+            if (socket.isInputShutdown()) {
+                super.clearReadFilter0();
+                return;
+            }
+            final ChannelConfig config = config();
+            final KQueueRecvByteAllocatorHandle allocHandle = recvBufAllocHandle();
+
+            final ChannelPipeline pipeline = pipeline();
+            allocHandle.reset(config);
+            readReadyBefore();
+
+            try {
+                readLoop: do {
+                    // lastBytesRead represents the fd. We use lastBytesRead because it must be set so that the
+                    // KQueueRecvByteAllocatorHandle knows if it should try to read again or not when autoRead is
+                    // enabled.
+                    int recvFd = socket.recvFd();
+                    switch(recvFd) {
+                        case 0:
+                            allocHandle.lastBytesRead(0);
+                            break readLoop;
+                        case -1:
+                            allocHandle.lastBytesRead(-1);
+                            close(voidPromise());
+                            return;
+                        default:
+                            allocHandle.lastBytesRead(1);
+                            allocHandle.incMessagesRead(1);
+                            readPending = false;
+                            pipeline.fireChannelRead(new FileDescriptor(recvFd));
+                            break;
+                    }
+                } while (allocHandle.continueReading());
+
+                allocHandle.readComplete();
+                pipeline.fireChannelReadComplete();
+            } catch (Throwable t) {
+                allocHandle.readComplete();
+                pipeline.fireChannelReadComplete();
+                pipeline.fireExceptionCaught(t);
+            } finally {
+                readReadyFinally(config);
+            }
+        }
+    }
+}

transport-native-kqueue/src/main/java/io/netty/channel/kqueue/KQueueDomainSocketChannelConfig.java

@@ -0,0 +1,154 @@
+/*
+ * Copyright 2016 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache License,
+ * version 2.0 (the "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at:
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+package io.netty.channel.kqueue;
+
+import io.netty.buffer.ByteBufAllocator;
+import io.netty.channel.ChannelOption;
+import io.netty.channel.MessageSizeEstimator;
+import io.netty.channel.RecvByteBufAllocator;
+import io.netty.channel.WriteBufferWaterMark;
+import io.netty.channel.unix.DomainSocketChannelConfig;
+import io.netty.channel.unix.DomainSocketReadMode;
+import io.netty.util.internal.UnstableApi;
+
+import java.util.Map;
+
+import static io.netty.channel.unix.UnixChannelOption.DOMAIN_SOCKET_READ_MODE;
+
+@UnstableApi
+public final class KQueueDomainSocketChannelConfig extends KQueueChannelConfig implements DomainSocketChannelConfig {
+    private volatile DomainSocketReadMode mode = DomainSocketReadMode.BYTES;
+
+    KQueueDomainSocketChannelConfig(AbstractKQueueChannel channel) {
+        super(channel);
+    }
+
+    @Override
+    public Map<ChannelOption<?>, Object> getOptions() {
+        return getOptions(super.getOptions(), DOMAIN_SOCKET_READ_MODE);
+    }
+
+    @SuppressWarnings("unchecked")
+    @Override
+    public <T> T getOption(ChannelOption<T> option) {
+        if (option == DOMAIN_SOCKET_READ_MODE) {
+            return (T) getReadMode();
+        }
+        return super.getOption(option);
+    }
+
+    @Override
+    public <T> boolean setOption(ChannelOption<T> option, T value) {
+        validate(option, value);
+
+        if (option == DOMAIN_SOCKET_READ_MODE) {
+            setReadMode((DomainSocketReadMode) value);
+        } else {
+            return super.setOption(option, value);
+        }
+
+        return true;
+    }
+
+    @Override
+    public KQueueDomainSocketChannelConfig setRcvAllocTransportProvidesGuess(boolean transportProvidesGuess) {
+        super.setRcvAllocTransportProvidesGuess(transportProvidesGuess);
+        return this;
+    }
+
+    @Override
+    @Deprecated
+    public KQueueDomainSocketChannelConfig setMaxMessagesPerRead(int maxMessagesPerRead) {
+        super.setMaxMessagesPerRead(maxMessagesPerRead);
+        return this;
+    }
+
+    @Override
+    public KQueueDomainSocketChannelConfig setConnectTimeoutMillis(int connectTimeoutMillis) {
+        super.setConnectTimeoutMillis(connectTimeoutMillis);
+        return this;
+    }
+
+    @Override
+    public KQueueDomainSocketChannelConfig setWriteSpinCount(int writeSpinCount) {
+        super.setWriteSpinCount(writeSpinCount);
+        return this;
+    }
+
+    @Override
+    public KQueueDomainSocketChannelConfig setRecvByteBufAllocator(RecvByteBufAllocator allocator) {
+        super.setRecvByteBufAllocator(allocator);
+        return this;
+    }
+
+    @Override
+    public KQueueDomainSocketChannelConfig setAllocator(ByteBufAllocator allocator) {
+        super.setAllocator(allocator);
+        return this;
+    }
+
+    @Override
+    public KQueueDomainSocketChannelConfig setAutoClose(boolean autoClose) {
+        super.setAutoClose(autoClose);
+        return this;
+    }
+
+    @Override
+    public KQueueDomainSocketChannelConfig setMessageSizeEstimator(MessageSizeEstimator estimator) {
+        super.setMessageSizeEstimator(estimator);
+        return this;
+    }
+
+    @Override
+    @Deprecated
+    public KQueueDomainSocketChannelConfig setWriteBufferLowWaterMark(int writeBufferLowWaterMark) {
+        super.setWriteBufferLowWaterMark(writeBufferLowWaterMark);
+        return this;
+    }
+
+    @Override
+    @Deprecated
+    public KQueueDomainSocketChannelConfig setWriteBufferHighWaterMark(int writeBufferHighWaterMark) {
+        super.setWriteBufferHighWaterMark(writeBufferHighWaterMark);
+        return this;
+    }
+
+    @Override
+    public KQueueDomainSocketChannelConfig setWriteBufferWaterMark(WriteBufferWaterMark writeBufferWaterMark) {
+        super.setWriteBufferWaterMark(writeBufferWaterMark);
+        return this;
+    }
+
+    @Override
+    public KQueueDomainSocketChannelConfig setAutoRead(boolean autoRead) {
+        super.setAutoRead(autoRead);
+        return this;
+    }
+
+    @Override
+    public KQueueDomainSocketChannelConfig setReadMode(DomainSocketReadMode mode) {
+        if (mode == null) {
+            throw new NullPointerException("mode");
+        }
+        this.mode = mode;
+        return this;
+    }
+
+    @Override
+    public DomainSocketReadMode getReadMode() {
+        return mode;
+    }
+}

transport-native-kqueue/src/main/java/io/netty/channel/kqueue/KQueueEventArray.java

@@ -0,0 +1,144 @@
+/*
+ * Copyright 2016 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache License,
+ * version 2.0 (the "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at:
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+package io.netty.channel.kqueue;
+
+import io.netty.util.internal.PlatformDependent;
+
+/**
+ * Represents an array of kevent structures, backed by offheap memory.
+ *
+ * struct kevent {
+ *  uintptr_t ident;
+ *  short     keventFilter;
+ *  u_short   flags;
+ *  u_int     fflags;
+ *  intptr_t  data;
+ *  void      *udata;
+ * };
+ */
+final class KQueueEventArray {
+    private static final int KQUEUE_EVENT_SIZE = Native.sizeofKEvent();
+    private static final int KQUEUE_IDENT_OFFSET = Native.offsetofKEventIdent();
+    private static final int KQUEUE_FILTER_OFFSET = Native.offsetofKEventFilter();
+    private static final int KQUEUE_FFLAGS_OFFSET = Native.offsetofKEventFFlags();
+    private static final int KQUEUE_FLAGS_OFFSET = Native.offsetofKEventFlags();
+    private static final int KQUEUE_DATA_OFFSET = Native.offsetofKeventData();
+
+    private long memoryAddress;
+    private int size;
+    private int capacity;
+
+    KQueueEventArray(int capacity) {
+        if (capacity < 1) {
+            throw new IllegalArgumentException("capacity must be >= 1 but was " + capacity);
+        }
+        memoryAddress = PlatformDependent.allocateMemory(capacity * KQUEUE_EVENT_SIZE);
+        this.capacity = capacity;
+    }
+
+    /**
+     * Return the {@code memoryAddress} which points to the start of this {@link KQueueEventArray}.
+     */
+    long memoryAddress() {
+        return memoryAddress;
+    }
+
+    /**
+     * Return the capacity of the {@link KQueueEventArray} which represent the maximum number of {@code kevent}s
+     * that can be stored in it.
+     */
+    int capacity() {
+        return capacity;
+    }
+
+    int size() {
+        return size;
+    }
+
+    void clear() {
+        size = 0;
+    }
+
+    void evSet(AbstractKQueueChannel ch, short filter, short flags, int fflags) {
+        checkSize();
+        evSet(getKEventOffset(size++), ch, ch.socket.intValue(), filter, flags, fflags);
+    }
+
+    private void checkSize() {
+        if (size == capacity) {
+            realloc(true);
+        }
+    }
+
+    /**
+     * Increase the storage of this {@link KQueueEventArray}.
+     */
+    void realloc(boolean throwIfFail) {
+        // Double the capacity while it is "sufficiently small", and otherwise increase by 50%.
+        int newLength = capacity <= 65536 ? capacity << 1 : capacity + capacity >> 1;
+        long newMemoryAddress = PlatformDependent.reallocateMemory(memoryAddress, newLength * KQUEUE_EVENT_SIZE);
+        if (newMemoryAddress != 0) {
+            memoryAddress = newMemoryAddress;
+            capacity = newLength;
+            return;
+        }
+        if (throwIfFail) {
+            throw new OutOfMemoryError("unable to allocate " + newLength + " new bytes! Existing capacity is: "
+                    + capacity);
+        }
+    }
+
+    /**
+     * Free this {@link KQueueEventArray}. Any usage after calling this method may segfault the JVM!
+     */
+    void free() {
+        PlatformDependent.freeMemory(memoryAddress);
+        memoryAddress = size = capacity = 0;
+    }
+
+    long getKEventOffset(int index) {
+        return memoryAddress + index * KQUEUE_EVENT_SIZE;
+    }
+
+    short flags(int index) {
+        return PlatformDependent.getShort(getKEventOffset(index) + KQUEUE_FLAGS_OFFSET);
+    }
+
+    short filter(int index) {
+        return PlatformDependent.getShort(getKEventOffset(index) + KQUEUE_FILTER_OFFSET);
+    }
+
+    short fflags(int index) {
+        return PlatformDependent.getShort(getKEventOffset(index) + KQUEUE_FFLAGS_OFFSET);
+    }
+
+    int fd(int index) {
+        return PlatformDependent.getInt(getKEventOffset(index) + KQUEUE_IDENT_OFFSET);
+    }
+
+    long data(int index) {
+        return PlatformDependent.getLong(getKEventOffset(index) + KQUEUE_DATA_OFFSET);
+    }
+
+    AbstractKQueueChannel channel(int index) {
+        return getChannel(getKEventOffset(index));
+    }
+
+    private static native void evSet(long keventAddress, AbstractKQueueChannel ch,
+                                     int ident, short filter, short flags, int fflags);
+    private static native AbstractKQueueChannel getChannel(long keventAddress);
+    static native void deleteGlobalRefs(long channelAddressStart, long channelAddressEnd);
+}

transport-native-kqueue/src/main/java/io/netty/channel/kqueue/KQueueEventLoop.java

@@ -0,0 +1,370 @@
+/*
+ * Copyright 2016 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache License,
+ * version 2.0 (the "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at:
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+package io.netty.channel.kqueue;
+
+import io.netty.channel.EventLoop;
+import io.netty.channel.EventLoopGroup;
+import io.netty.channel.SelectStrategy;
+import io.netty.channel.SingleThreadEventLoop;
+import io.netty.channel.kqueue.AbstractKQueueChannel.AbstractKQueueUnsafe;
+import io.netty.channel.unix.FileDescriptor;
+import io.netty.channel.unix.IovArray;
+import io.netty.util.IntSupplier;
+import io.netty.util.concurrent.RejectedExecutionHandler;
+import io.netty.util.internal.ObjectUtil;
+import io.netty.util.internal.PlatformDependent;
+import io.netty.util.internal.logging.InternalLogger;
+import io.netty.util.internal.logging.InternalLoggerFactory;
+
+import java.io.IOException;
+import java.util.Queue;
+import java.util.concurrent.Callable;
+import java.util.concurrent.Executor;
+import java.util.concurrent.atomic.AtomicIntegerFieldUpdater;
+
+import static io.netty.channel.kqueue.KQueueEventArray.deleteGlobalRefs;
+import static java.lang.Math.min;
+
+/**
+ * {@link EventLoop} which uses kqueue under the covers. Only works on BSD!
+ */
+final class KQueueEventLoop extends SingleThreadEventLoop {
+    private static final InternalLogger logger = InternalLoggerFactory.getInstance(KQueueEventLoop.class);
+    private static final AtomicIntegerFieldUpdater<KQueueEventLoop> WAKEN_UP_UPDATER =
+            AtomicIntegerFieldUpdater.newUpdater(KQueueEventLoop.class, "wakenUp");
+    private static final int KQUEUE_WAKE_UP_IDENT = 0;
+
+    static {
+        // Ensure JNI is initialized by the time this class is loaded by this time!
+        // We use unix-common methods in this class which are backed by JNI methods.
+        KQueue.ensureAvailability();
+    }
+
+    private final NativeLongArray jniChannelPointers;
+    private final boolean allowGrowing;
+    private final FileDescriptor kqueueFd;
+    private final KQueueEventArray changeList;
+    private final KQueueEventArray eventList;
+    private final SelectStrategy selectStrategy;
+    private final IovArray iovArray = new IovArray();
+    private final IntSupplier selectNowSupplier = new IntSupplier() {
+        @Override
+        public int get() throws Exception {
+            return kqueueWaitNow();
+        }
+    };
+    private final Callable<Integer> pendingTasksCallable = new Callable<Integer>() {
+        @Override
+        public Integer call() throws Exception {
+            return KQueueEventLoop.super.pendingTasks();
+        }
+    };
+
+    private volatile int wakenUp;
+    private volatile int ioRatio = 50;
+
+    KQueueEventLoop(EventLoopGroup parent, Executor executor, int maxEvents,
+                    SelectStrategy strategy, RejectedExecutionHandler rejectedExecutionHandler) {
+        super(parent, executor, false, DEFAULT_MAX_PENDING_TASKS, rejectedExecutionHandler);
+        selectStrategy = ObjectUtil.checkNotNull(strategy, "strategy");
+        this.kqueueFd = Native.newKQueue();
+        if (maxEvents == 0) {
+            allowGrowing = true;
+            maxEvents = 4096;
+        } else {
+            allowGrowing = false;
+        }
+        changeList = new KQueueEventArray(maxEvents);
+        eventList = new KQueueEventArray(maxEvents);
+        jniChannelPointers = new NativeLongArray(4096);
+        int result = Native.keventAddUserEvent(kqueueFd.intValue(), KQUEUE_WAKE_UP_IDENT);
+        if (result < 0) {
+            cleanup();
+            throw new IllegalStateException("kevent failed to add user event with errno: " + (-result));
+        }
+    }
+
+    void evSet(AbstractKQueueChannel ch, short filter, short flags, int fflags) {
+        changeList.evSet(ch, filter, flags, fflags);
+    }
+
+    void remove(AbstractKQueueChannel ch) throws IOException {
+        assert inEventLoop();
+        if (ch.jniSelfPtr == 0) {
+            return;
+        }
+
+        jniChannelPointers.add(ch.jniSelfPtr);
+        ch.jniSelfPtr = 0;
+    }
+
+    /**
+     * Return a cleared {@link IovArray} that can be used for writes in this {@link EventLoop}.
+     */
+    IovArray cleanArray() {
+        iovArray.clear();
+        return iovArray;
+    }
+
+    @Override
+    protected void wakeup(boolean inEventLoop) {
+        if (!inEventLoop && WAKEN_UP_UPDATER.compareAndSet(this, 0, 1)) {
+            wakeup();
+        }
+    }
+
+    private void wakeup() {
+        Native.keventTriggerUserEvent(kqueueFd.intValue(), KQUEUE_WAKE_UP_IDENT);
+        // Note that the result may return an error (e.g. errno = EBADF after the event loop has been shutdown).
+        // So it is not very practical to assert the return value is always >= 0.
+    }
+
+    private int kqueueWait(boolean oldWakeup) throws IOException {
+        // TODO(scott): do we need to loop here ... we already loop in keventWait to ensure we wait the expected time.
+        // We also do the same thing in EPOLL ... do we need to loop there?
+
+        // If a task was submitted when wakenUp value was 1, the task didn't get a chance to produce wakeup event.
+        // So we need to check task queue again before calling epoll_wait. If we don't, the task might be pended
+        // until epoll_wait was timed out. It might be pended until idle timeout if IdleStateHandler existed
+        // in pipeline.
+        if (oldWakeup && hasTasks()) {
+            return kqueueWaitNow();
+        }
+
+        long totalDelay = delayNanos(System.nanoTime());
+        int delaySeconds = (int) min(totalDelay / 1000000000L, Integer.MAX_VALUE);
+        return kqueueWait(delaySeconds, (int) min(totalDelay - delaySeconds * 1000000000L, Integer.MAX_VALUE));
+    }
+
+    private int kqueueWaitNow() throws IOException {
+        return kqueueWait(0, 0);
+    }
+
+    private int kqueueWait(int timeoutSec, int timeoutNs) throws IOException {
+        deleteJniChannelPointers();
+        int numEvents = Native.keventWait(kqueueFd.intValue(), changeList, eventList, timeoutSec, timeoutNs);
+        changeList.clear();
+        return numEvents;
+    }
+
+    private void deleteJniChannelPointers() {
+        if (!jniChannelPointers.isEmpty()) {
+            deleteGlobalRefs(jniChannelPointers.memoryAddress(), jniChannelPointers.memoryAddressEnd());
+            jniChannelPointers.clear();
+        }
+    }
+
+    private void processReady(int ready) {
+        for (int i = 0; i < ready; ++i) {
+            final short filter = eventList.filter(i);
+            final short flags = eventList.flags(i);
+            if (filter == Native.EVFILT_USER || (flags & Native.EV_ERROR) != 0) {
+                // EV_ERROR is returned if the FD is closed synchronously (which removes from kqueue) and then
+                // we later attempt to delete the filters from kqueue.
+                assert filter != Native.EVFILT_USER ||
+                        (filter == Native.EVFILT_USER && eventList.fd(i) == KQUEUE_WAKE_UP_IDENT);
+                continue;
+            }
+
+            AbstractKQueueChannel channel = eventList.channel(i);
+            if (channel == null) {
+                // This may happen if the channel has already been closed, and it will be removed from kqueue anyways.
+                // We also handle EV_ERROR above to skip this even early if it is a result of a referencing a closed and
+                // thus removed from kqueue FD.
+                logger.warn("events[{}]=[{}, {}] had no channel!", i, eventList.fd(i), filter);
+                continue;
+            }
+
+            AbstractKQueueUnsafe unsafe = (AbstractKQueueUnsafe) channel.unsafe();
+            // First check for EPOLLOUT as we may need to fail the connect ChannelPromise before try
+            // to read from the file descriptor.
+            if (filter == Native.EVFILT_WRITE) {
+                unsafe.writeReady();
+            } else if (filter == Native.EVFILT_READ) {
+                // Check READ before EOF to ensure all data is read before shutting down the input.
+                unsafe.readReady(eventList.data(i));
+            }
+
+            // Check if EV_EOF was set, this will notify us for connection-reset in which case
+            // we may close the channel directly or try to read more data depending on the state of the
+            // Channel and also depending on the AbstractKQueueChannel subtype.
+            if ((flags & Native.EV_EOF) != 0) {
+                unsafe.readEOF();
+            }
+        }
+    }
+
+    @Override
+    protected void run() {
+        for (;;) {
+            try {
+                int strategy = selectStrategy.calculateStrategy(selectNowSupplier, hasTasks());
+                switch (strategy) {
+                    case SelectStrategy.CONTINUE:
+                        continue;
+                    case SelectStrategy.SELECT:
+                        strategy = kqueueWait(WAKEN_UP_UPDATER.getAndSet(this, 0) == 1);
+
+                        // 'wakenUp.compareAndSet(false, true)' is always evaluated
+                        // before calling 'selector.wakeup()' to reduce the wake-up
+                        // overhead. (Selector.wakeup() is an expensive operation.)
+                        //
+                        // However, there is a race condition in this approach.
+                        // The race condition is triggered when 'wakenUp' is set to
+                        // true too early.
+                        //
+                        // 'wakenUp' is set to true too early if:
+                        // 1) Selector is waken up between 'wakenUp.set(false)' and
+                        //    'selector.select(...)'. (BAD)
+                        // 2) Selector is waken up between 'selector.select(...)' and
+                        //    'if (wakenUp.get()) { ... }'. (OK)
+                        //
+                        // In the first case, 'wakenUp' is set to true and the
+                        // following 'selector.select(...)' will wake up immediately.
+                        // Until 'wakenUp' is set to false again in the next round,
+                        // 'wakenUp.compareAndSet(false, true)' will fail, and therefore
+                        // any attempt to wake up the Selector will fail, too, causing
+                        // the following 'selector.select(...)' call to block
+                        // unnecessarily.
+                        //
+                        // To fix this problem, we wake up the selector again if wakenUp
+                        // is true immediately after selector.select(...).
+                        // It is inefficient in that it wakes up the selector for both
+                        // the first case (BAD - wake-up required) and the second case
+                        // (OK - no wake-up required).
+
+                        if (wakenUp == 1) {
+                            wakeup();
+                        }
+                    default:
+                        // fallthrough
+                }
+
+                final int ioRatio = this.ioRatio;
+                if (ioRatio == 100) {
+                    try {
+                        if (strategy > 0) {
+                            processReady(strategy);
+                        }
+                    } finally {
+                        runAllTasks();
+                    }
+                } else {
+                    final long ioStartTime = System.nanoTime();
+
+                    try {
+                        if (strategy > 0) {
+                            processReady(strategy);
+                        }
+                    } finally {
+                        final long ioTime = System.nanoTime() - ioStartTime;
+                        runAllTasks(ioTime * (100 - ioRatio) / ioRatio);
+                    }
+                }
+                if (allowGrowing && strategy == eventList.capacity()) {
+                    //increase the size of the array as we needed the whole space for the events
+                    eventList.realloc(false);
+                }
+            } catch (Throwable t) {
+                handleLoopException(t);
+            }
+            // Always handle shutdown even if the loop processing threw an exception.
+            try {
+                if (isShuttingDown()) {
+                    closeAll();
+                    if (confirmShutdown()) {
+                        break;
+                    }
+                }
+            } catch (Throwable t) {
+                handleLoopException(t);
+            }
+        }
+    }
+
+    @Override
+    protected Queue<Runnable> newTaskQueue(int maxPendingTasks) {
+        // This event loop never calls takeTask()
+        return PlatformDependent.newMpscQueue(maxPendingTasks);
+    }
+
+    @Override
+    public int pendingTasks() {
+        // As we use a MpscQueue we need to ensure pendingTasks() is only executed from within the EventLoop as
+        // otherwise we may see unexpected behavior (as size() is only allowed to be called by a single consumer).
+        // See https://github.com/netty/netty/issues/5297
+        return inEventLoop() ? super.pendingTasks() : submit(pendingTasksCallable).syncUninterruptibly().getNow();
+    }
+
+    /**
+     * Returns the percentage of the desired amount of time spent for I/O in the event loop.
+     */
+    public int getIoRatio() {
+        return ioRatio;
+    }
+
+    /**
+     * Sets the percentage of the desired amount of time spent for I/O in the event loop.  The default value is
+     * {@code 50}, which means the event loop will try to spend the same amount of time for I/O as for non-I/O tasks.
+     */
+    public void setIoRatio(int ioRatio) {
+        if (ioRatio <= 0 || ioRatio > 100) {
+            throw new IllegalArgumentException("ioRatio: " + ioRatio + " (expected: 0 < ioRatio <= 100)");
+        }
+        this.ioRatio = ioRatio;
+    }
+
+    @Override
+    protected void cleanup() {
+        try {
+            try {
+                kqueueFd.close();
+            } catch (IOException e) {
+                logger.warn("Failed to close the kqueue fd.", e);
+            }
+        } finally {
+            // Cleanup all native memory!
+
+            // The JNI channel pointers should already be deleted because we should wait on kevent before this method,
+            // but lets just be sure we cleanup native memory.
+            deleteJniChannelPointers();
+            jniChannelPointers.free();
+
+            changeList.free();
+            eventList.free();
+        }
+    }
+
+    private void closeAll() {
+        try {
+            kqueueWaitNow();
+        } catch (IOException e) {
+            // ignore on close
+        }
+    }
+
+    private static void handleLoopException(Throwable t) {
+        logger.warn("Unexpected exception in the selector loop.", t);
+
+        // Prevent possible consecutive immediate failures that lead to
+        // excessive CPU consumption.
+        try {
+            Thread.sleep(1000);
+        } catch (InterruptedException e) {
+            // Ignore.
+        }
+    }
+}

transport-native-kqueue/src/main/java/io/netty/channel/kqueue/KQueueEventLoopGroup.java

@@ -0,0 +1,134 @@
+/*
+ * Copyright 2016 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache License,
+ * version 2.0 (the "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at:
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+package io.netty.channel.kqueue;
+
+import io.netty.channel.DefaultSelectStrategyFactory;
+import io.netty.channel.EventLoop;
+import io.netty.channel.MultithreadEventLoopGroup;
+import io.netty.channel.SelectStrategyFactory;
+import io.netty.util.concurrent.EventExecutor;
+import io.netty.util.concurrent.EventExecutorChooserFactory;
+import io.netty.util.concurrent.RejectedExecutionHandler;
+import io.netty.util.concurrent.RejectedExecutionHandlers;
+import io.netty.util.internal.UnstableApi;
+
+import java.util.concurrent.Executor;
+import java.util.concurrent.ThreadFactory;
+
+@UnstableApi
+public final class KQueueEventLoopGroup extends MultithreadEventLoopGroup {
+    static {
+        // Ensure JNI is initialized by the time this class is loaded by this time!
+        KQueue.ensureAvailability();
+    }
+    /**
+     * Create a new instance using the default number of threads and the default {@link ThreadFactory}.
+     */
+    public KQueueEventLoopGroup() {
+        this(0);
+    }
+
+    /**
+     * Create a new instance using the specified number of threads and the default {@link ThreadFactory}.
+     */
+    public KQueueEventLoopGroup(int nThreads) {
+        this(nThreads, (ThreadFactory) null);
+    }
+
+    /**
+     * Create a new instance using the specified number of threads and the default {@link ThreadFactory}.
+     */
+    @SuppressWarnings("deprecation")
+    public KQueueEventLoopGroup(int nThreads, SelectStrategyFactory selectStrategyFactory) {
+        this(nThreads, (ThreadFactory) null, selectStrategyFactory);
+    }
+
+    /**
+     * Create a new instance using the specified number of threads and the given {@link ThreadFactory}.
+     */
+    @SuppressWarnings("deprecation")
+    public KQueueEventLoopGroup(int nThreads, ThreadFactory threadFactory) {
+        this(nThreads, threadFactory, 0);
+    }
+
+    public KQueueEventLoopGroup(int nThreads, Executor executor) {
+        this(nThreads, executor, DefaultSelectStrategyFactory.INSTANCE);
+    }
+
+    /**
+     * Create a new instance using the specified number of threads and the given {@link ThreadFactory}.
+     */
+    @SuppressWarnings("deprecation")
+    public KQueueEventLoopGroup(int nThreads, ThreadFactory threadFactory,
+                                SelectStrategyFactory selectStrategyFactory) {
+        this(nThreads, threadFactory, 0, selectStrategyFactory);
+    }
+
+    /**
+     * Create a new instance using the specified number of threads, the given {@link ThreadFactory} and the given
+     * maximal amount of epoll events to handle per epollWait(...).
+     *
+     * @deprecated  Use {@link #KQueueEventLoopGroup(int)} or {@link #KQueueEventLoopGroup(int, ThreadFactory)}
+     */
+    @Deprecated
+    public KQueueEventLoopGroup(int nThreads, ThreadFactory threadFactory, int maxEventsAtOnce) {
+        this(nThreads, threadFactory, maxEventsAtOnce, DefaultSelectStrategyFactory.INSTANCE);
+    }
+
+    /**
+     * Create a new instance using the specified number of threads, the given {@link ThreadFactory} and the given
+     * maximal amount of epoll events to handle per epollWait(...).
+     *
+     * @deprecated  Use {@link #KQueueEventLoopGroup(int)}, {@link #KQueueEventLoopGroup(int, ThreadFactory)}, or
+     * {@link #KQueueEventLoopGroup(int, SelectStrategyFactory)}
+     */
+    @Deprecated
+    public KQueueEventLoopGroup(int nThreads, ThreadFactory threadFactory, int maxEventsAtOnce,
+                               SelectStrategyFactory selectStrategyFactory) {
+        super(nThreads, threadFactory, maxEventsAtOnce, selectStrategyFactory, RejectedExecutionHandlers.reject());
+    }
+
+    public KQueueEventLoopGroup(int nThreads, Executor executor, SelectStrategyFactory selectStrategyFactory) {
+        super(nThreads, executor, 0, selectStrategyFactory, RejectedExecutionHandlers.reject());
+    }
+
+    public KQueueEventLoopGroup(int nThreads, Executor executor, EventExecutorChooserFactory chooserFactory,
+                               SelectStrategyFactory selectStrategyFactory) {
+        super(nThreads, executor, chooserFactory, 0, selectStrategyFactory, RejectedExecutionHandlers.reject());
+    }
+
+    public KQueueEventLoopGroup(int nThreads, Executor executor, EventExecutorChooserFactory chooserFactory,
+                               SelectStrategyFactory selectStrategyFactory,
+                               RejectedExecutionHandler rejectedExecutionHandler) {
+        super(nThreads, executor, chooserFactory, 0, selectStrategyFactory, rejectedExecutionHandler);
+    }
+
+    /**
+     * Sets the percentage of the desired amount of time spent for I/O in the child event loops.  The default value is
+     * {@code 50}, which means the event loop will try to spend the same amount of time for I/O as for non-I/O tasks.
+     */
+    public void setIoRatio(int ioRatio) {
+        for (EventExecutor e: this) {
+            ((KQueueEventLoop) e).setIoRatio(ioRatio);
+        }
+    }
+
+    @Override
+    protected EventLoop newChild(Executor executor, Object... args) throws Exception {
+        return new KQueueEventLoop(this, executor, (Integer) args[0],
+                ((SelectStrategyFactory) args[1]).newSelectStrategy(), (RejectedExecutionHandler) args[2]);
+    }
+}

transport-native-kqueue/src/main/java/io/netty/channel/kqueue/KQueueRecvByteAllocatorHandle.java

@@ -0,0 +1,127 @@
+/*
+ * Copyright 2016 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache License,
+ * version 2.0 (the "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at:
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+package io.netty.channel.kqueue;
+
+import io.netty.buffer.ByteBuf;
+import io.netty.buffer.ByteBufAllocator;
+import io.netty.channel.ChannelConfig;
+import io.netty.channel.RecvByteBufAllocator;
+import io.netty.util.UncheckedBooleanSupplier;
+import io.netty.util.internal.ObjectUtil;
+
+import static java.lang.Math.max;
+import static java.lang.Math.min;
+
+final class KQueueRecvByteAllocatorHandle implements RecvByteBufAllocator.ExtendedHandle {
+    private final RecvByteBufAllocator.ExtendedHandle delegate;
+    private final UncheckedBooleanSupplier defaultMaybeMoreDataSupplier = new UncheckedBooleanSupplier() {
+        @Override
+        public boolean get() {
+            return maybeMoreDataToRead();
+        }
+    };
+    private boolean overrideGuess;
+    private boolean readEOF;
+    private long numberBytesPending;
+
+    KQueueRecvByteAllocatorHandle(RecvByteBufAllocator.ExtendedHandle handle) {
+        this.delegate = ObjectUtil.checkNotNull(handle, "handle");
+    }
+
+    @Override
+    public int guess() {
+        return overrideGuess ? guess0() : delegate.guess();
+    }
+
+    @Override
+    public void reset(ChannelConfig config) {
+        overrideGuess = ((KQueueChannelConfig) config).getRcvAllocTransportProvidesGuess();
+        delegate.reset(config);
+    }
+
+    @Override
+    public void incMessagesRead(int numMessages) {
+        delegate.incMessagesRead(numMessages);
+    }
+
+    @Override
+    public ByteBuf allocate(ByteBufAllocator alloc) {
+        return overrideGuess ? alloc.ioBuffer(guess0()) : delegate.allocate(alloc);
+    }
+
+    @Override
+    public void lastBytesRead(int bytes) {
+        numberBytesPending = bytes < 0 ? 0 : max(0, numberBytesPending - bytes);
+        delegate.lastBytesRead(bytes);
+    }
+
+    @Override
+    public int lastBytesRead() {
+        return delegate.lastBytesRead();
+    }
+
+    @Override
+    public void attemptedBytesRead(int bytes) {
+        delegate.attemptedBytesRead(bytes);
+    }
+
+    @Override
+    public int attemptedBytesRead() {
+        return delegate.attemptedBytesRead();
+    }
+
+    @Override
+    public void readComplete() {
+        delegate.readComplete();
+    }
+
+    @Override
+    public boolean continueReading(UncheckedBooleanSupplier maybeMoreDataSupplier) {
+        return delegate.continueReading(maybeMoreDataSupplier);
+    }
+
+    @Override
+    public boolean continueReading() {
+        // We must override the supplier which determines if there maybe more data to read.
+        return delegate.continueReading(defaultMaybeMoreDataSupplier);
+    }
+
+    void readEOF() {
+        readEOF = true;
+    }
+
+    void numberBytesPending(long numberBytesPending) {
+        this.numberBytesPending = numberBytesPending;
+    }
+
+    boolean maybeMoreDataToRead() {
+        /**
+         * kqueue with EV_CLEAR flag set requires that we read until we consume "data" bytes
+         * (see <a href="https://www.freebsd.org/cgi/man.cgi?kqueue">kqueue man</a>). However in order to
+         * respect auto read we supporting reading to stop if auto read is off. If auto read is on we force reading to
+         * continue to avoid a {@link StackOverflowError} between channelReadComplete and reading from the
+         * channel. It is expected that the {@link #KQueueSocketChannel} implementations will track if all data was not
+         * read, and will force a EVFILT_READ ready event.
+         *
+         * If EOF has been read we must read until we get an error.
+         */
+        return numberBytesPending != 0 || readEOF;
+    }
+
+    private int guess0() {
+        return (int) min(numberBytesPending, Integer.MAX_VALUE);
+    }
+}

transport-native-kqueue/src/main/java/io/netty/channel/kqueue/KQueueServerChannelConfig.java

@@ -0,0 +1,201 @@
+/*
+ * Copyright 2016 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache License,
+ * version 2.0 (the "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at:
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+package io.netty.channel.kqueue;
+
+import io.netty.buffer.ByteBufAllocator;
+import io.netty.channel.ChannelException;
+import io.netty.channel.ChannelOption;
+import io.netty.channel.MessageSizeEstimator;
+import io.netty.channel.RecvByteBufAllocator;
+import io.netty.channel.WriteBufferWaterMark;
+import io.netty.channel.socket.ServerSocketChannelConfig;
+import io.netty.util.NetUtil;
+import io.netty.util.internal.UnstableApi;
+
+import java.io.IOException;
+import java.util.Map;
+
+import static io.netty.channel.ChannelOption.SO_BACKLOG;
+import static io.netty.channel.ChannelOption.SO_RCVBUF;
+import static io.netty.channel.ChannelOption.SO_REUSEADDR;
+
+@UnstableApi
+public class KQueueServerChannelConfig extends KQueueChannelConfig implements ServerSocketChannelConfig {
+    protected final AbstractKQueueChannel channel;
+    private volatile int backlog = NetUtil.SOMAXCONN;
+
+    KQueueServerChannelConfig(AbstractKQueueChannel channel) {
+        super(channel);
+        this.channel = channel;
+    }
+
+    @Override
+    public Map<ChannelOption<?>, Object> getOptions() {
+        return getOptions(super.getOptions(), SO_RCVBUF, SO_REUSEADDR, SO_BACKLOG);
+    }
+
+    @SuppressWarnings("unchecked")
+    @Override
+    public <T> T getOption(ChannelOption<T> option) {
+        if (option == SO_RCVBUF) {
+            return (T) Integer.valueOf(getReceiveBufferSize());
+        }
+        if (option == SO_REUSEADDR) {
+            return (T) Boolean.valueOf(isReuseAddress());
+        }
+        if (option == SO_BACKLOG) {
+            return (T) Integer.valueOf(getBacklog());
+        }
+        return super.getOption(option);
+    }
+
+    @Override
+    public <T> boolean setOption(ChannelOption<T> option, T value) {
+        validate(option, value);
+
+        if (option == SO_RCVBUF) {
+            setReceiveBufferSize((Integer) value);
+        } else if (option == SO_REUSEADDR) {
+            setReuseAddress((Boolean) value);
+        } else if (option == SO_BACKLOG) {
+            setBacklog((Integer) value);
+        } else {
+            return super.setOption(option, value);
+        }
+
+        return true;
+    }
+
+    public boolean isReuseAddress() {
+        try {
+            return channel.socket.isReuseAddress();
+        } catch (IOException e) {
+            throw new ChannelException(e);
+        }
+    }
+
+    public KQueueServerChannelConfig setReuseAddress(boolean reuseAddress) {
+        try {
+            channel.socket.setReuseAddress(reuseAddress);
+            return this;
+        } catch (IOException e) {
+            throw new ChannelException(e);
+        }
+    }
+
+    public int getReceiveBufferSize() {
+        try {
+            return channel.socket.getReceiveBufferSize();
+        } catch (IOException e) {
+            throw new ChannelException(e);
+        }
+    }
+
+    public KQueueServerChannelConfig setReceiveBufferSize(int receiveBufferSize) {
+        try {
+            channel.socket.setReceiveBufferSize(receiveBufferSize);
+            return this;
+        } catch (IOException e) {
+            throw new ChannelException(e);
+        }
+    }
+
+    public int getBacklog() {
+        return backlog;
+    }
+
+    public KQueueServerChannelConfig setBacklog(int backlog) {
+        if (backlog < 0) {
+            throw new IllegalArgumentException("backlog: " + backlog);
+        }
+        this.backlog = backlog;
+        return this;
+    }
+
+    @Override
+    public KQueueServerChannelConfig setRcvAllocTransportProvidesGuess(boolean transportProvidesGuess) {
+        super.setRcvAllocTransportProvidesGuess(transportProvidesGuess);
+        return this;
+    }
+
+    @Override
+    public KQueueServerChannelConfig setPerformancePreferences(int connectionTime, int latency, int bandwidth) {
+        return this;
+    }
+
+    @Override
+    public KQueueServerChannelConfig setConnectTimeoutMillis(int connectTimeoutMillis) {
+        super.setConnectTimeoutMillis(connectTimeoutMillis);
+        return this;
+    }
+
+    @Override
+    @Deprecated
+    public KQueueServerChannelConfig setMaxMessagesPerRead(int maxMessagesPerRead) {
+        super.setMaxMessagesPerRead(maxMessagesPerRead);
+        return this;
+    }
+
+    @Override
+    public KQueueServerChannelConfig setWriteSpinCount(int writeSpinCount) {
+        super.setWriteSpinCount(writeSpinCount);
+        return this;
+    }
+
+    @Override
+    public KQueueServerChannelConfig setAllocator(ByteBufAllocator allocator) {
+        super.setAllocator(allocator);
+        return this;
+    }
+
+    @Override
+    public KQueueServerChannelConfig setRecvByteBufAllocator(RecvByteBufAllocator allocator) {
+        super.setRecvByteBufAllocator(allocator);
+        return this;
+    }
+
+    @Override
+    public KQueueServerChannelConfig setAutoRead(boolean autoRead) {
+        super.setAutoRead(autoRead);
+        return this;
+    }
+
+    @Override
+    @Deprecated
+    public KQueueServerChannelConfig setWriteBufferHighWaterMark(int writeBufferHighWaterMark) {
+        super.setWriteBufferHighWaterMark(writeBufferHighWaterMark);
+        return this;
+    }
+
+    @Override
+    @Deprecated
+    public KQueueServerChannelConfig setWriteBufferLowWaterMark(int writeBufferLowWaterMark) {
+        super.setWriteBufferLowWaterMark(writeBufferLowWaterMark);
+        return this;
+    }
+
+    @Override
+    public KQueueServerChannelConfig setWriteBufferWaterMark(WriteBufferWaterMark writeBufferWaterMark) {
+        super.setWriteBufferWaterMark(writeBufferWaterMark);
+        return this;
+    }
+
+    @Override
+    public KQueueServerChannelConfig setMessageSizeEstimator(MessageSizeEstimator estimator) {
+        super.setMessageSizeEstimator(estimator);
+        return this;
+    }
+}

transport-native-kqueue/src/main/java/io/netty/channel/kqueue/KQueueServerDomainSocketChannel.java

@@ -0,0 +1,96 @@
+/*
+ * Copyright 2016 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache License,
+ * version 2.0 (the "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at:
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+package io.netty.channel.kqueue;
+
+import io.netty.channel.Channel;
+import io.netty.channel.unix.DomainSocketAddress;
+import io.netty.channel.unix.ServerDomainSocketChannel;
+import io.netty.util.internal.UnstableApi;
+import io.netty.util.internal.logging.InternalLogger;
+import io.netty.util.internal.logging.InternalLoggerFactory;
+
+import java.io.File;
+import java.net.SocketAddress;
+
+import static io.netty.channel.kqueue.BsdSocket.newSocketDomain;
+
+@UnstableApi
+public final class KQueueServerDomainSocketChannel extends AbstractKQueueServerChannel
+                                                  implements ServerDomainSocketChannel {
+    private static final InternalLogger logger = InternalLoggerFactory.getInstance(
+            KQueueServerDomainSocketChannel.class);
+
+    private final KQueueServerChannelConfig config = new KQueueServerChannelConfig(this);
+    private volatile DomainSocketAddress local;
+
+    public KQueueServerDomainSocketChannel() {
+        super(newSocketDomain(), false);
+    }
+
+    KQueueServerDomainSocketChannel(BsdSocket socket, boolean active) {
+        super(socket, active);
+    }
+
+    @Override
+    protected Channel newChildChannel(int fd, byte[] addr, int offset, int len) throws Exception {
+        return new KQueueDomainSocketChannel(this, new BsdSocket(fd));
+    }
+
+    @Override
+    protected DomainSocketAddress localAddress0() {
+        return local;
+    }
+
+    @Override
+    protected void doBind(SocketAddress localAddress) throws Exception {
+        socket.bind(localAddress);
+        socket.listen(config.getBacklog());
+        local = (DomainSocketAddress) localAddress;
+        active = true;
+    }
+
+    @Override
+    protected void doClose() throws Exception {
+        try {
+            super.doClose();
+        } finally {
+            DomainSocketAddress local = this.local;
+            if (local != null) {
+                // Delete the socket file if possible.
+                File socketFile = new File(local.path());
+                boolean success = socketFile.delete();
+                if (!success && logger.isDebugEnabled()) {
+                    logger.debug("Failed to delete a domain socket file: {}", local.path());
+                }
+            }
+        }
+    }
+
+    @Override
+    public KQueueServerChannelConfig config() {
+        return config;
+    }
+
+    @Override
+    public DomainSocketAddress remoteAddress() {
+        return (DomainSocketAddress) super.remoteAddress();
+    }
+
+    @Override
+    public DomainSocketAddress localAddress() {
+        return (DomainSocketAddress) super.localAddress();
+    }
+}

transport-native-kqueue/src/main/java/io/netty/channel/kqueue/KQueueServerSocketChannel.java

@@ -0,0 +1,87 @@
+/*
+ * Copyright 2016 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache License,
+ * version 2.0 (the "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at:
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+package io.netty.channel.kqueue;
+
+import io.netty.channel.Channel;
+import io.netty.channel.EventLoop;
+import io.netty.channel.socket.ServerSocketChannel;
+import io.netty.util.internal.UnstableApi;
+
+import java.net.InetSocketAddress;
+import java.net.SocketAddress;
+
+import static io.netty.channel.kqueue.BsdSocket.newSocketStream;
+import static io.netty.channel.unix.NativeInetAddress.address;
+
+@UnstableApi
+public final class KQueueServerSocketChannel extends AbstractKQueueServerChannel implements ServerSocketChannel {
+    private final KQueueServerSocketChannelConfig config;
+    private volatile InetSocketAddress local;
+
+    public KQueueServerSocketChannel() {
+        super(newSocketStream(), false);
+        config = new KQueueServerSocketChannelConfig(this);
+    }
+
+    KQueueServerSocketChannel(BsdSocket fd, boolean active) {
+        super(fd, active);
+        config = new KQueueServerSocketChannelConfig(this);
+        // As we create an KQueueServerSocketChannel from a FileDescriptor we should try to obtain the remote and local
+        // address from it. This is needed as the FileDescriptor may be bound already.
+        local = fd.localAddress();
+    }
+
+    @Override
+    protected boolean isCompatible(EventLoop loop) {
+        return loop instanceof KQueueEventLoop;
+    }
+
+    @Override
+    protected void doBind(SocketAddress localAddress) throws Exception {
+        InetSocketAddress addr = (InetSocketAddress) localAddress;
+        checkResolvable(addr);
+        socket.bind(addr);
+        local = socket.localAddress();
+        // TODO(scott): tcp fast open here!
+        socket.listen(config.getBacklog());
+        active = true;
+    }
+
+    @Override
+    public InetSocketAddress remoteAddress() {
+        return (InetSocketAddress) super.remoteAddress();
+    }
+
+    @Override
+    public InetSocketAddress localAddress() {
+        return (InetSocketAddress) super.localAddress();
+    }
+
+    @Override
+    public KQueueServerSocketChannelConfig config() {
+        return config;
+    }
+
+    @Override
+    protected InetSocketAddress localAddress0() {
+        return local;
+    }
+
+    @Override
+    protected Channel newChildChannel(int fd, byte[] address, int offset, int len) throws Exception {
+        return new KQueueSocketChannel(this, new BsdSocket(fd), address(address, offset, len));
+    }
+}

transport-native-kqueue/src/main/java/io/netty/channel/kqueue/KQueueServerSocketChannelConfig.java

@@ -0,0 +1,201 @@
+/*
+ * Copyright 2016 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache License,
+ * version 2.0 (the "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at:
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+package io.netty.channel.kqueue;
+
+import io.netty.buffer.ByteBufAllocator;
+import io.netty.channel.ChannelException;
+import io.netty.channel.ChannelOption;
+import io.netty.channel.MessageSizeEstimator;
+import io.netty.channel.RecvByteBufAllocator;
+import io.netty.channel.WriteBufferWaterMark;
+import io.netty.channel.socket.ServerSocketChannelConfig;
+import io.netty.util.internal.UnstableApi;
+
+import java.io.IOException;
+import java.util.Map;
+
+import static io.netty.channel.kqueue.KQueueChannelOption.SO_ACCEPTFILTER;
+import static io.netty.channel.unix.UnixChannelOption.SO_REUSEPORT;
+
+@UnstableApi
+public class KQueueServerSocketChannelConfig extends KQueueServerChannelConfig implements ServerSocketChannelConfig {
+    KQueueServerSocketChannelConfig(KQueueServerSocketChannel channel) {
+        super(channel);
+
+        // Use SO_REUSEADDR by default as java.nio does the same.
+        //
+        // See https://github.com/netty/netty/issues/2605
+        setReuseAddress(true);
+    }
+
+    @Override
+    public Map<ChannelOption<?>, Object> getOptions() {
+        return getOptions(super.getOptions(), SO_REUSEPORT, SO_ACCEPTFILTER);
+    }
+
+    @SuppressWarnings("unchecked")
+    @Override
+    public <T> T getOption(ChannelOption<T> option) {
+        if (option == SO_REUSEPORT) {
+            return (T) Boolean.valueOf(isReusePort());
+        }
+        if (option == SO_ACCEPTFILTER) {
+            return (T) getAcceptFilter();
+        }
+        return super.getOption(option);
+    }
+
+    @Override
+    public <T> boolean setOption(ChannelOption<T> option, T value) {
+        validate(option, value);
+
+        if (option == SO_REUSEPORT) {
+            setReusePort((Boolean) value);
+        } else if (option == SO_ACCEPTFILTER) {
+            setAcceptFilter((AcceptFilter) value);
+        } else {
+            return super.setOption(option, value);
+        }
+
+        return true;
+    }
+
+    public KQueueServerSocketChannelConfig setReusePort(boolean reusePort) {
+        try {
+            channel.socket.setReusePort(reusePort);
+            return this;
+        } catch (IOException e) {
+            throw new ChannelException(e);
+        }
+    }
+
+    public boolean isReusePort() {
+        try {
+            return channel.socket.isReusePort();
+        } catch (IOException e) {
+            throw new ChannelException(e);
+        }
+    }
+
+    public KQueueServerSocketChannelConfig setAcceptFilter(AcceptFilter acceptFilter) {
+        try {
+            channel.socket.setAcceptFilter(acceptFilter);
+            return this;
+        } catch (IOException e) {
+            throw new ChannelException(e);
+        }
+    }
+
+    public AcceptFilter getAcceptFilter() {
+        try {
+            return channel.socket.getAcceptFilter();
+        } catch (IOException e) {
+            throw new ChannelException(e);
+        }
+    }
+
+    @Override
+    public KQueueServerSocketChannelConfig setRcvAllocTransportProvidesGuess(boolean transportProvidesGuess) {
+        super.setRcvAllocTransportProvidesGuess(transportProvidesGuess);
+        return this;
+    }
+
+    @Override
+    public KQueueServerSocketChannelConfig setReuseAddress(boolean reuseAddress) {
+        super.setReuseAddress(reuseAddress);
+        return this;
+    }
+
+    @Override
+    public KQueueServerSocketChannelConfig setReceiveBufferSize(int receiveBufferSize) {
+        super.setReceiveBufferSize(receiveBufferSize);
+        return this;
+    }
+
+    @Override
+    public KQueueServerSocketChannelConfig setPerformancePreferences(int connectionTime, int latency, int bandwidth) {
+        return this;
+    }
+
+    @Override
+    public KQueueServerSocketChannelConfig setBacklog(int backlog) {
+        super.setBacklog(backlog);
+        return this;
+    }
+
+    @Override
+    public KQueueServerSocketChannelConfig setConnectTimeoutMillis(int connectTimeoutMillis) {
+        super.setConnectTimeoutMillis(connectTimeoutMillis);
+        return this;
+    }
+
+    @Override
+    @Deprecated
+    public KQueueServerSocketChannelConfig setMaxMessagesPerRead(int maxMessagesPerRead) {
+        super.setMaxMessagesPerRead(maxMessagesPerRead);
+        return this;
+    }
+
+    @Override
+    public KQueueServerSocketChannelConfig setWriteSpinCount(int writeSpinCount) {
+        super.setWriteSpinCount(writeSpinCount);
+        return this;
+    }
+
+    @Override
+    public KQueueServerSocketChannelConfig setAllocator(ByteBufAllocator allocator) {
+        super.setAllocator(allocator);
+        return this;
+    }
+
+    @Override
+    public KQueueServerSocketChannelConfig setRecvByteBufAllocator(RecvByteBufAllocator allocator) {
+        super.setRecvByteBufAllocator(allocator);
+        return this;
+    }
+
+    @Override
+    public KQueueServerSocketChannelConfig setAutoRead(boolean autoRead) {
+        super.setAutoRead(autoRead);
+        return this;
+    }
+
+    @Override
+    @Deprecated
+    public KQueueServerSocketChannelConfig setWriteBufferHighWaterMark(int writeBufferHighWaterMark) {
+        super.setWriteBufferHighWaterMark(writeBufferHighWaterMark);
+        return this;
+    }
+
+    @Override
+    @Deprecated
+    public KQueueServerSocketChannelConfig setWriteBufferLowWaterMark(int writeBufferLowWaterMark) {
+        super.setWriteBufferLowWaterMark(writeBufferLowWaterMark);
+        return this;
+    }
+
+    @Override
+    public KQueueServerSocketChannelConfig setWriteBufferWaterMark(WriteBufferWaterMark writeBufferWaterMark) {
+        super.setWriteBufferWaterMark(writeBufferWaterMark);
+        return this;
+    }
+
+    @Override
+    public KQueueServerSocketChannelConfig setMessageSizeEstimator(MessageSizeEstimator estimator) {
+        super.setMessageSizeEstimator(estimator);
+        return this;
+    }
+}

transport-native-kqueue/src/main/java/io/netty/channel/kqueue/KQueueSocketChannel.java

@@ -0,0 +1,176 @@
+/*
+ * Copyright 2016 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache License,
+ * version 2.0 (the "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at:
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+package io.netty.channel.kqueue;
+
+import io.netty.channel.Channel;
+import io.netty.channel.socket.ServerSocketChannel;
+import io.netty.channel.socket.SocketChannel;
+import io.netty.util.concurrent.GlobalEventExecutor;
+import io.netty.util.internal.PlatformDependent;
+import io.netty.util.internal.UnstableApi;
+
+import java.net.InetAddress;
+import java.net.InetSocketAddress;
+import java.net.SocketAddress;
+import java.net.UnknownHostException;
+import java.nio.channels.AlreadyConnectedException;
+import java.util.concurrent.Executor;
+
+@UnstableApi
+public final class KQueueSocketChannel extends AbstractKQueueStreamChannel implements SocketChannel {
+    private final KQueueSocketChannelConfig config;
+
+    private volatile InetSocketAddress local;
+    private volatile InetSocketAddress remote;
+    private InetSocketAddress requestedRemote;
+
+    public KQueueSocketChannel() {
+        super(null, BsdSocket.newSocketStream(), false);
+        config = new KQueueSocketChannelConfig(this);
+    }
+
+    KQueueSocketChannel(Channel parent, BsdSocket fd, InetSocketAddress remote) {
+        super(parent, fd, true);
+        config = new KQueueSocketChannelConfig(this);
+        // Directly cache the remote and local addresses
+        // See https://github.com/netty/netty/issues/2359
+        this.remote = remote;
+        local = fd.localAddress();
+    }
+
+    @Override
+    public InetSocketAddress remoteAddress() {
+        return (InetSocketAddress) super.remoteAddress();
+    }
+
+    @Override
+    public InetSocketAddress localAddress() {
+        return (InetSocketAddress) super.localAddress();
+    }
+
+    @Override
+    protected SocketAddress localAddress0() {
+        return local;
+    }
+
+    @Override
+    protected SocketAddress remoteAddress0() {
+        return remote;
+    }
+
+    @Override
+    protected void doBind(SocketAddress local) throws Exception {
+        InetSocketAddress localAddress = (InetSocketAddress) local;
+        socket.bind(localAddress);
+        this.local = socket.localAddress();
+    }
+
+    @Override
+    public KQueueSocketChannelConfig config() {
+        return config;
+    }
+
+    @Override
+    public ServerSocketChannel parent() {
+        return (ServerSocketChannel) super.parent();
+    }
+
+    @Override
+    protected AbstractKQueueUnsafe newUnsafe() {
+        return new KQueueSocketChannelUnsafe();
+    }
+
+    private static InetSocketAddress computeRemoteAddr(InetSocketAddress remoteAddr, InetSocketAddress osRemoteAddr) {
+        if (osRemoteAddr != null) {
+            if (PlatformDependent.javaVersion() >= 7) {
+                try {
+                    // Only try to construct a new InetSocketAddress if we using java >= 7 as getHostString() does not
+                    // exists in earlier releases and so the retrieval of the hostname could block the EventLoop if a
+                    // reverse lookup would be needed.
+                    return new InetSocketAddress(InetAddress.getByAddress(remoteAddr.getHostString(),
+                            osRemoteAddr.getAddress().getAddress()),
+                            osRemoteAddr.getPort());
+                } catch (UnknownHostException ignore) {
+                    // Should never happen but fallback to osRemoteAddr anyway.
+                }
+            }
+            return osRemoteAddr;
+        }
+        return remoteAddr;
+    }
+
+    @Override
+    protected boolean doConnect(SocketAddress remoteAddress, SocketAddress localAddress) throws Exception {
+        if (localAddress != null) {
+            checkResolvable((InetSocketAddress) localAddress);
+        }
+        InetSocketAddress remoteAddr = (InetSocketAddress) remoteAddress;
+        checkResolvable(remoteAddr);
+
+        if (remote != null) {
+            // Check if already connected before trying to connect. This is needed as connect(...) will not return -1
+            // and set errno to EISCONN if a previous connect(...) attempt was setting errno to EINPROGRESS and finished
+            // later.
+            throw new AlreadyConnectedException();
+        }
+
+        boolean connected = super.doConnect(remoteAddress, localAddress);
+        if (connected) {
+            remote = computeRemoteAddr(remoteAddr, socket.remoteAddress());
+        } else {
+            // Store for later usage in doFinishConnect()
+            requestedRemote = remoteAddr;
+        }
+        // We always need to set the localAddress even if not connected yet as the bind already took place.
+        //
+        // See https://github.com/netty/netty/issues/3463
+        local = socket.localAddress();
+        return connected;
+    }
+
+    private final class KQueueSocketChannelUnsafe extends KQueueStreamUnsafe {
+        @Override
+        protected Executor prepareToClose() {
+            try {
+                // Check isOpen() first as otherwise it will throw a RuntimeException
+                // when call getSoLinger() as the fd is not valid anymore.
+                if (isOpen() && config().getSoLinger() > 0) {
+                    // We need to cancel this key of the channel so we may not end up in a eventloop spin
+                    // because we try to read or write until the actual close happens which may be later due
+                    // SO_LINGER handling.
+                    // See https://github.com/netty/netty/issues/4449
+                    ((KQueueEventLoop) eventLoop()).remove(KQueueSocketChannel.this);
+                    return GlobalEventExecutor.INSTANCE;
+                }
+            } catch (Throwable ignore) {
+                // Ignore the error as the underlying channel may be closed in the meantime and so
+                // getSoLinger() may produce an exception. In this case we just return null.
+                // See https://github.com/netty/netty/issues/4449
+            }
+            return null;
+        }
+
+        @Override
+        boolean doFinishConnect() throws Exception {
+            if (super.doFinishConnect()) {
+                remote = computeRemoteAddr(requestedRemote, socket.remoteAddress());
+                requestedRemote = null;
+                return true;
+            }
+            return false;
+        }
+    }
+}

transport-native-kqueue/src/main/java/io/netty/channel/kqueue/KQueueSocketChannelConfig.java

@@ -0,0 +1,386 @@
+/*
+ * Copyright 2016 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache License,
+ * version 2.0 (the "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at:
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+package io.netty.channel.kqueue;
+
+import io.netty.buffer.ByteBufAllocator;
+import io.netty.channel.ChannelException;
+import io.netty.channel.ChannelOption;
+import io.netty.channel.MessageSizeEstimator;
+import io.netty.channel.RecvByteBufAllocator;
+import io.netty.channel.WriteBufferWaterMark;
+import io.netty.channel.socket.SocketChannelConfig;
+import io.netty.util.internal.PlatformDependent;
+import io.netty.util.internal.UnstableApi;
+
+import java.io.IOException;
+import java.util.Map;
+
+import static io.netty.channel.ChannelOption.ALLOW_HALF_CLOSURE;
+import static io.netty.channel.ChannelOption.IP_TOS;
+import static io.netty.channel.ChannelOption.SO_KEEPALIVE;
+import static io.netty.channel.ChannelOption.SO_LINGER;
+import static io.netty.channel.ChannelOption.SO_RCVBUF;
+import static io.netty.channel.ChannelOption.SO_REUSEADDR;
+import static io.netty.channel.ChannelOption.SO_SNDBUF;
+import static io.netty.channel.ChannelOption.TCP_NODELAY;
+import static io.netty.channel.kqueue.KQueueChannelOption.SO_SNDLOWAT;
+import static io.netty.channel.kqueue.KQueueChannelOption.TCP_NOPUSH;
+
+@UnstableApi
+public final class KQueueSocketChannelConfig extends KQueueChannelConfig implements SocketChannelConfig {
+    private final KQueueSocketChannel channel;
+    private volatile boolean allowHalfClosure;
+
+    KQueueSocketChannelConfig(KQueueSocketChannel channel) {
+        super(channel);
+        this.channel = channel;
+        if (PlatformDependent.canEnableTcpNoDelayByDefault()) {
+            setTcpNoDelay(true);
+        }
+    }
+
+    @Override
+    public Map<ChannelOption<?>, Object> getOptions() {
+        return getOptions(
+                super.getOptions(),
+                SO_RCVBUF, SO_SNDBUF, TCP_NODELAY, SO_KEEPALIVE, SO_REUSEADDR, SO_LINGER, IP_TOS,
+                ALLOW_HALF_CLOSURE, SO_SNDLOWAT, TCP_NOPUSH);
+    }
+
+    @SuppressWarnings("unchecked")
+    @Override
+    public <T> T getOption(ChannelOption<T> option) {
+        if (option == SO_RCVBUF) {
+            return (T) Integer.valueOf(getReceiveBufferSize());
+        }
+        if (option == SO_SNDBUF) {
+            return (T) Integer.valueOf(getSendBufferSize());
+        }
+        if (option == TCP_NODELAY) {
+            return (T) Boolean.valueOf(isTcpNoDelay());
+        }
+        if (option == SO_KEEPALIVE) {
+            return (T) Boolean.valueOf(isKeepAlive());
+        }
+        if (option == SO_REUSEADDR) {
+            return (T) Boolean.valueOf(isReuseAddress());
+        }
+        if (option == SO_LINGER) {
+            return (T) Integer.valueOf(getSoLinger());
+        }
+        if (option == IP_TOS) {
+            return (T) Integer.valueOf(getTrafficClass());
+        }
+        if (option == ALLOW_HALF_CLOSURE) {
+            return (T) Boolean.valueOf(isAllowHalfClosure());
+        }
+        if (option == SO_SNDLOWAT) {
+            return (T) Integer.valueOf(getSndLowAt());
+        }
+        if (option == TCP_NOPUSH) {
+            return (T) Boolean.valueOf(isTcpNoPush());
+        }
+        return super.getOption(option);
+    }
+
+    @Override
+    public <T> boolean setOption(ChannelOption<T> option, T value) {
+        validate(option, value);
+
+        if (option == SO_RCVBUF) {
+            setReceiveBufferSize((Integer) value);
+        } else if (option == SO_SNDBUF) {
+            setSendBufferSize((Integer) value);
+        } else if (option == TCP_NODELAY) {
+            setTcpNoDelay((Boolean) value);
+        } else if (option == SO_KEEPALIVE) {
+            setKeepAlive((Boolean) value);
+        } else if (option == SO_REUSEADDR) {
+            setReuseAddress((Boolean) value);
+        } else if (option == SO_LINGER) {
+            setSoLinger((Integer) value);
+        } else if (option == IP_TOS) {
+            setTrafficClass((Integer) value);
+        } else if (option == ALLOW_HALF_CLOSURE) {
+            setAllowHalfClosure((Boolean) value);
+        } else if (option == SO_SNDLOWAT) {
+            setSndLowAt((Integer) value);
+        } else if (option == TCP_NOPUSH) {
+            setTcpNoPush((Boolean) value);
+        } else {
+            return super.setOption(option, value);
+        }
+
+        return true;
+    }
+
+    @Override
+    public int getReceiveBufferSize() {
+        try {
+            return channel.socket.getReceiveBufferSize();
+        } catch (IOException e) {
+            throw new ChannelException(e);
+        }
+    }
+
+    @Override
+    public int getSendBufferSize() {
+        try {
+            return channel.socket.getSendBufferSize();
+        } catch (IOException e) {
+            throw new ChannelException(e);
+        }
+    }
+
+    @Override
+    public int getSoLinger() {
+        try {
+            return channel.socket.getSoLinger();
+        } catch (IOException e) {
+            throw new ChannelException(e);
+        }
+    }
+
+    @Override
+    public int getTrafficClass() {
+        try {
+            return channel.socket.getTrafficClass();
+        } catch (IOException e) {
+            throw new ChannelException(e);
+        }
+    }
+
+    @Override
+    public boolean isKeepAlive() {
+        try {
+            return channel.socket.isKeepAlive();
+        } catch (IOException e) {
+            throw new ChannelException(e);
+        }
+    }
+
+    @Override
+    public boolean isReuseAddress() {
+        try {
+            return channel.socket.isReuseAddress();
+        } catch (IOException e) {
+            throw new ChannelException(e);
+        }
+    }
+
+    @Override
+    public boolean isTcpNoDelay() {
+        try {
+            return channel.socket.isTcpNoDelay();
+        } catch (IOException e) {
+            throw new ChannelException(e);
+        }
+    }
+
+    public int getSndLowAt() {
+        try {
+            return channel.socket.getSndLowAt();
+        } catch (IOException e) {
+            throw new ChannelException(e);
+        }
+    }
+
+    public void setSndLowAt(int sndLowAt)  {
+        try {
+            channel.socket.setSndLowAt(sndLowAt);
+        } catch (IOException e) {
+            throw new ChannelException(e);
+        }
+    }
+
+    public boolean isTcpNoPush() {
+        try {
+            return channel.socket.isTcpNoPush();
+        } catch (IOException e) {
+            throw new ChannelException(e);
+        }
+    }
+
+    public void setTcpNoPush(boolean tcpNoPush)  {
+        try {
+            channel.socket.setTcpNoPush(tcpNoPush);
+        } catch (IOException e) {
+            throw new ChannelException(e);
+        }
+    }
+
+    @Override
+    public KQueueSocketChannelConfig setKeepAlive(boolean keepAlive) {
+        try {
+            channel.socket.setKeepAlive(keepAlive);
+            return this;
+        } catch (IOException e) {
+            throw new ChannelException(e);
+        }
+    }
+
+    @Override
+    public KQueueSocketChannelConfig setReceiveBufferSize(int receiveBufferSize) {
+        try {
+            channel.socket.setReceiveBufferSize(receiveBufferSize);
+            return this;
+        } catch (IOException e) {
+            throw new ChannelException(e);
+        }
+    }
+
+    @Override
+    public KQueueSocketChannelConfig setReuseAddress(boolean reuseAddress) {
+        try {
+            channel.socket.setReuseAddress(reuseAddress);
+            return this;
+        } catch (IOException e) {
+            throw new ChannelException(e);
+        }
+    }
+
+    @Override
+    public KQueueSocketChannelConfig setSendBufferSize(int sendBufferSize) {
+        try {
+            channel.socket.setSendBufferSize(sendBufferSize);
+            return this;
+        } catch (IOException e) {
+            throw new ChannelException(e);
+        }
+    }
+
+    @Override
+    public KQueueSocketChannelConfig setSoLinger(int soLinger) {
+        try {
+            channel.socket.setSoLinger(soLinger);
+            return this;
+        } catch (IOException e) {
+            throw new ChannelException(e);
+        }
+    }
+
+    @Override
+    public KQueueSocketChannelConfig setTcpNoDelay(boolean tcpNoDelay) {
+        try {
+            channel.socket.setTcpNoDelay(tcpNoDelay);
+            return this;
+        } catch (IOException e) {
+            throw new ChannelException(e);
+        }
+    }
+
+    @Override
+    public KQueueSocketChannelConfig setTrafficClass(int trafficClass) {
+        try {
+            channel.socket.setTrafficClass(trafficClass);
+            return this;
+        } catch (IOException e) {
+            throw new ChannelException(e);
+        }
+    }
+
+    @Override
+    public boolean isAllowHalfClosure() {
+        return allowHalfClosure;
+    }
+
+    @Override
+    public KQueueSocketChannelConfig setRcvAllocTransportProvidesGuess(boolean transportProvidesGuess) {
+        super.setRcvAllocTransportProvidesGuess(transportProvidesGuess);
+        return this;
+    }
+
+    @Override
+    public KQueueSocketChannelConfig setPerformancePreferences(
+            int connectionTime, int latency, int bandwidth) {
+        return this;
+    }
+
+    @Override
+    public KQueueSocketChannelConfig setAllowHalfClosure(boolean allowHalfClosure) {
+        this.allowHalfClosure = allowHalfClosure;
+        return this;
+    }
+
+    @Override
+    public KQueueSocketChannelConfig setConnectTimeoutMillis(int connectTimeoutMillis) {
+        super.setConnectTimeoutMillis(connectTimeoutMillis);
+        return this;
+    }
+
+    @Override
+    @Deprecated
+    public KQueueSocketChannelConfig setMaxMessagesPerRead(int maxMessagesPerRead) {
+        super.setMaxMessagesPerRead(maxMessagesPerRead);
+        return this;
+    }
+
+    @Override
+    public KQueueSocketChannelConfig setWriteSpinCount(int writeSpinCount) {
+        super.setWriteSpinCount(writeSpinCount);
+        return this;
+    }
+
+    @Override
+    public KQueueSocketChannelConfig setAllocator(ByteBufAllocator allocator) {
+        super.setAllocator(allocator);
+        return this;
+    }
+
+    @Override
+    public KQueueSocketChannelConfig setRecvByteBufAllocator(RecvByteBufAllocator allocator) {
+        super.setRecvByteBufAllocator(allocator);
+        return this;
+    }
+
+    @Override
+    public KQueueSocketChannelConfig setAutoRead(boolean autoRead) {
+        super.setAutoRead(autoRead);
+        return this;
+    }
+
+    @Override
+    public KQueueSocketChannelConfig setAutoClose(boolean autoClose) {
+        super.setAutoClose(autoClose);
+        return this;
+    }
+
+    @Override
+    @Deprecated
+    public KQueueSocketChannelConfig setWriteBufferHighWaterMark(int writeBufferHighWaterMark) {
+        super.setWriteBufferHighWaterMark(writeBufferHighWaterMark);
+        return this;
+    }
+
+    @Override
+    @Deprecated
+    public KQueueSocketChannelConfig setWriteBufferLowWaterMark(int writeBufferLowWaterMark) {
+        super.setWriteBufferLowWaterMark(writeBufferLowWaterMark);
+        return this;
+    }
+
+    @Override
+    public KQueueSocketChannelConfig setWriteBufferWaterMark(WriteBufferWaterMark writeBufferWaterMark) {
+        super.setWriteBufferWaterMark(writeBufferWaterMark);
+        return this;
+    }
+
+    @Override
+    public KQueueSocketChannelConfig setMessageSizeEstimator(MessageSizeEstimator estimator) {
+        super.setMessageSizeEstimator(estimator);
+        return this;
+    }
+}

transport-native-kqueue/src/main/java/io/netty/channel/kqueue/KQueueStaticallyReferencedJniMethods.java

@@ -0,0 +1,43 @@
+/*
+ * Copyright 2016 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache License,
+ * version 2.0 (the "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at:
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+package io.netty.channel.kqueue;
+
+/**
+ * This class is necessary to break the following cyclic dependency:
+ * <ol>
+ * <li>JNI_OnLoad</li>
+ * <li>JNI Calls FindClass because RegisterNatives (used to register JNI methods) requires a class</li>
+ * <li>FindClass loads the class, but static members variables of that class attempt to call a JNI method which has not
+ * yet been registered.</li>
+ * <li>java.lang.UnsatisfiedLinkError is thrown because native method has not yet been registered.</li>
+ * </ol>
+ * Static members which call JNI methods must not be declared in this class!
+ */
+final class KQueueStaticallyReferencedJniMethods {
+    private KQueueStaticallyReferencedJniMethods() { }
+
+    static native short evAdd();
+    static native short evEnable();
+    static native short evDisable();
+    static native short evDelete();
+    static native short evClear();
+    static native short evEOF();
+    static native short evError();
+
+    static native short evfiltRead();
+    static native short evfiltWrite();
+    static native short evfiltUser();
+}

transport-native-kqueue/src/main/java/io/netty/channel/kqueue/Native.java

@@ -0,0 +1,110 @@
+/*
+ * Copyright 2016 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache License,
+ * version 2.0 (the "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at:
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+package io.netty.channel.kqueue;
+
+import io.netty.channel.unix.FileDescriptor;
+import io.netty.util.internal.NativeLibraryLoader;
+import io.netty.util.internal.PlatformDependent;
+import io.netty.util.internal.SystemPropertyUtil;
+
+import java.io.IOException;
+import java.util.Locale;
+
+import static io.netty.channel.kqueue.KQueueStaticallyReferencedJniMethods.evAdd;
+import static io.netty.channel.kqueue.KQueueStaticallyReferencedJniMethods.evClear;
+import static io.netty.channel.kqueue.KQueueStaticallyReferencedJniMethods.evDelete;
+import static io.netty.channel.kqueue.KQueueStaticallyReferencedJniMethods.evDisable;
+import static io.netty.channel.kqueue.KQueueStaticallyReferencedJniMethods.evEOF;
+import static io.netty.channel.kqueue.KQueueStaticallyReferencedJniMethods.evEnable;
+import static io.netty.channel.kqueue.KQueueStaticallyReferencedJniMethods.evError;
+import static io.netty.channel.kqueue.KQueueStaticallyReferencedJniMethods.evfiltRead;
+import static io.netty.channel.kqueue.KQueueStaticallyReferencedJniMethods.evfiltUser;
+import static io.netty.channel.kqueue.KQueueStaticallyReferencedJniMethods.evfiltWrite;
+import static io.netty.channel.unix.Errors.newIOException;
+
+/**
+ * Navite helper methods
+ * <p><strong>Internal usage only!</strong>
+ */
+final class Native {
+    static {
+        try {
+            // First, try calling a side-effect free JNI method to see if the library was already
+            // loaded by the application.
+            sizeofKEvent();
+        } catch (UnsatisfiedLinkError ignore) {
+            // The library was not previously loaded, load it now.
+            loadNativeLibrary();
+        }
+    }
+
+    static final short EV_ADD = evAdd();
+    static final short EV_ENABLE = evEnable();
+    static final short EV_DISABLE = evDisable();
+    static final short EV_DELETE = evDelete();
+    static final short EV_CLEAR = evClear();
+    static final short EV_ERROR = evError();
+    static final short EV_EOF = evEOF();
+
+    // Commonly used combinations of EV defines
+    static final short EV_ADD_CLEAR_ENABLE = (short) (EV_ADD | EV_CLEAR | EV_ENABLE);
+    static final short EV_DELETE_DISABLE = (short) (EV_DELETE | EV_DISABLE);
+
+    static final short EVFILT_READ = evfiltRead();
+    static final short EVFILT_WRITE = evfiltWrite();
+    static final short EVFILT_USER = evfiltUser();
+
+    static FileDescriptor newKQueue() {
+        return new FileDescriptor(kqueueCreate());
+    }
+
+    static int keventWait(int kqueueFd, KQueueEventArray changeList, KQueueEventArray eventList,
+                          int tvSec, int tvNsec) throws IOException {
+        int ready = keventWait(kqueueFd, changeList.memoryAddress(), changeList.size(),
+                               eventList.memoryAddress(), eventList.capacity(), tvSec, tvNsec);
+        if (ready < 0) {
+            throw newIOException("kevent", ready);
+        }
+        return ready;
+    }
+
+    private static native int kqueueCreate();
+    private static native int keventWait(int kqueueFd, long changeListAddress, int changeListLength,
+                                         long eventListAddress, int eventListLength, int tvSec, int tvNsec);
+    static native int keventTriggerUserEvent(int kqueueFd, int ident);
+    static native int keventAddUserEvent(int kqueueFd, int ident);
+
+    // kevent related
+    static native int sizeofKEvent();
+    static native int offsetofKEventIdent();
+    static native int offsetofKEventFlags();
+    static native int offsetofKEventFFlags();
+    static native int offsetofKEventFilter();
+    static native int offsetofKeventData();
+
+    private static void loadNativeLibrary() {
+        String name = SystemPropertyUtil.get("os.name").toLowerCase(Locale.UK).trim();
+        if (!name.startsWith("mac") && !name.contains("bsd") && !name.startsWith("darwin")) {
+            throw new IllegalStateException("Only supported on BSD");
+        }
+        NativeLibraryLoader.load(SystemPropertyUtil.get("io.netty.packagePrefix", "").replace('.', '-') +
+                "netty-transport-native-kqueue", PlatformDependent.getClassLoader(Native.class));
+    }
+
+    private Native() {
+        // utility
+    }
+}

transport-native-kqueue/src/main/java/io/netty/channel/kqueue/NativeLongArray.java

@@ -0,0 +1,87 @@
+/*
+ * Copyright 2016 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache License,
+ * version 2.0 (the "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at:
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+package io.netty.channel.kqueue;
+
+import io.netty.util.internal.PlatformDependent;
+
+import static io.netty.channel.unix.Limits.SIZEOF_JLONG;
+
+final class NativeLongArray {
+    private long memoryAddress;
+    private int capacity;
+    private int size;
+
+    NativeLongArray(int capacity) {
+        if (capacity < 1) {
+            throw new IllegalArgumentException("capacity must be >= 1 but was " + capacity);
+        }
+        memoryAddress = PlatformDependent.allocateMemory(capacity * SIZEOF_JLONG);
+        this.capacity = capacity;
+    }
+
+    void add(long value) {
+        checkSize();
+        PlatformDependent.putLong(memoryOffset(size++), value);
+    }
+
+    void clear() {
+        size = 0;
+    }
+
+    boolean isEmpty() {
+        return size == 0;
+    }
+
+    void free() {
+        PlatformDependent.freeMemory(memoryAddress);
+        memoryAddress = 0;
+    }
+
+    long memoryAddress() {
+        return memoryAddress;
+    }
+
+    long memoryAddressEnd() {
+        return memoryOffset(size);
+    }
+
+    private long memoryOffset(int index) {
+        return memoryAddress + index * SIZEOF_JLONG;
+    }
+
+    private void checkSize() {
+        if (size == capacity) {
+            realloc();
+        }
+    }
+
+    private void realloc() {
+        // Double the capacity while it is "sufficiently small", and otherwise increase by 50%.
+        int newLength = capacity <= 65536 ? capacity << 1 : capacity + capacity >> 1;
+        long newMemoryAddress = PlatformDependent.reallocateMemory(memoryAddress, newLength * SIZEOF_JLONG);
+        if (newMemoryAddress == 0) {
+            throw new OutOfMemoryError("unable to allocate " + newLength + " new bytes! Existing capacity is: "
+                    + capacity);
+        }
+        memoryAddress = newMemoryAddress;
+        capacity = newLength;
+    }
+
+    @Override
+    public String toString() {
+        return "memoryAddress: " + memoryAddress + " capacity: " + capacity + " size: " + size;
+    }
+}

transport-native-kqueue/src/main/java/io/netty/channel/kqueue/package-info.java

@@ -0,0 +1,23 @@
+/*
+ * Copyright 2016 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache License,
+ * version 2.0 (the "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at:
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+
+/**
+ * BSD specific transport.
+ */
+@UnstableApi
+package io.netty.channel.kqueue;
+
+import io.netty.util.internal.UnstableApi;

transport-native-kqueue/src/test/java/io/netty/channel/kqueue/KQueueAbstractDomainSocketEchoTest.java

@@ -0,0 +1,27 @@
+/*
+ * Copyright 2016 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache License,
+ * version 2.0 (the "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at:
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+package io.netty.channel.kqueue;
+
+import io.netty.channel.unix.DomainSocketAddress;
+import java.net.SocketAddress;
+import java.util.UUID;
+
+public class KQueueAbstractDomainSocketEchoTest extends KQueueDomainSocketEchoTest {
+    @Override
+    protected SocketAddress newSocketAddress() {
+        return new DomainSocketAddress(System.getProperty("java.io.tmpdir") + UUID.randomUUID());
+    }
+}

transport-native-kqueue/src/test/java/io/netty/channel/kqueue/KQueueChannelConfigTest.java

@@ -0,0 +1,55 @@
+/*
+ * Copyright 2016 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache License,
+ * version 2.0 (the "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at:
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+package io.netty.channel.kqueue;
+
+import io.netty.channel.ChannelException;
+import org.junit.Before;
+import org.junit.Test;
+
+import static org.junit.Assert.fail;
+
+public class KQueueChannelConfigTest {
+    @Before
+    public void before() {
+        KQueue.ensureAvailability();
+    }
+
+    @Test
+    public void testOptionGetThrowsChannelException() throws Exception {
+        KQueueSocketChannel channel = new KQueueSocketChannel();
+        channel.config().getSoLinger();
+        channel.fd().close();
+        try {
+            channel.config().getSoLinger();
+            fail();
+        } catch (ChannelException e) {
+            // expected
+        }
+    }
+
+    @Test
+    public void testOptionSetThrowsChannelException() throws Exception {
+        KQueueSocketChannel channel = new KQueueSocketChannel();
+        channel.config().setKeepAlive(true);
+        channel.fd().close();
+        try {
+            channel.config().setKeepAlive(true);
+            fail();
+        } catch (ChannelException e) {
+            // expected
+        }
+    }
+}

transport-native-kqueue/src/test/java/io/netty/channel/kqueue/KQueueDatagramUnicastTest.java

@@ -0,0 +1,29 @@
+/*
+ * Copyright 2016 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache License,
+ * version 2.0 (the "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at:
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+package io.netty.channel.kqueue;
+
+import io.netty.bootstrap.Bootstrap;
+import io.netty.testsuite.transport.TestsuitePermutation;
+import io.netty.testsuite.transport.socket.DatagramUnicastTest;
+
+import java.util.List;
+
+public class KQueueDatagramUnicastTest extends DatagramUnicastTest {
+    @Override
+    protected List<TestsuitePermutation.BootstrapComboFactory<Bootstrap, Bootstrap>> newFactories() {
+        return KQueueSocketTestPermutation.INSTANCE.datagram();
+    }
+}

transport-native-kqueue/src/test/java/io/netty/channel/kqueue/KQueueDomainSocketEchoTest.java

@@ -0,0 +1,35 @@
+/*
+ * Copyright 2016 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache License,
+ * version 2.0 (the "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at:
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+package io.netty.channel.kqueue;
+
+import io.netty.bootstrap.Bootstrap;
+import io.netty.bootstrap.ServerBootstrap;
+import io.netty.testsuite.transport.TestsuitePermutation;
+
+import java.net.SocketAddress;
+import java.util.List;
+
+public class KQueueDomainSocketEchoTest extends KQueueSocketEchoTest {
+    @Override
+    protected SocketAddress newSocketAddress() {
+        return KQueueSocketTestPermutation.newSocketAddress();
+    }
+
+    @Override
+    protected List<TestsuitePermutation.BootstrapComboFactory<ServerBootstrap, Bootstrap>> newFactories() {
+        return KQueueSocketTestPermutation.INSTANCE.domainSocket();
+    }
+}

transport-native-kqueue/src/test/java/io/netty/channel/kqueue/KQueueDomainSocketFdTest.java

@@ -0,0 +1,104 @@
+/*
+ * Copyright 2016 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache License,
+ * version 2.0 (the "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at:
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+package io.netty.channel.kqueue;
+
+import io.netty.bootstrap.Bootstrap;
+import io.netty.bootstrap.ServerBootstrap;
+import io.netty.channel.Channel;
+import io.netty.channel.ChannelFuture;
+import io.netty.channel.ChannelFutureListener;
+import io.netty.channel.ChannelHandlerContext;
+import io.netty.channel.ChannelInboundHandlerAdapter;
+import io.netty.channel.unix.DomainSocketReadMode;
+import io.netty.channel.unix.FileDescriptor;
+import io.netty.testsuite.transport.TestsuitePermutation;
+import io.netty.testsuite.transport.socket.AbstractSocketTest;
+import org.junit.Assert;
+import org.junit.Test;
+
+import java.net.SocketAddress;
+import java.util.List;
+import java.util.concurrent.BlockingQueue;
+import java.util.concurrent.LinkedBlockingQueue;
+
+public class KQueueDomainSocketFdTest extends AbstractSocketTest {
+    @Override
+    protected SocketAddress newSocketAddress() {
+        return KQueueSocketTestPermutation.newSocketAddress();
+    }
+
+    @Override
+    protected List<TestsuitePermutation.BootstrapComboFactory<ServerBootstrap, Bootstrap>> newFactories() {
+        return KQueueSocketTestPermutation.INSTANCE.domainSocket();
+    }
+
+    @Test(timeout = 30000)
+    public void testSendRecvFd() throws Throwable {
+        run();
+    }
+
+    public void testSendRecvFd(ServerBootstrap sb, Bootstrap cb) throws Throwable {
+        final BlockingQueue<Object> queue = new LinkedBlockingQueue<Object>(1);
+        sb.childHandler(new ChannelInboundHandlerAdapter() {
+            @Override
+            public void channelActive(ChannelHandlerContext ctx) throws Exception {
+                // Create new channel and obtain a file descriptor from it.
+                final KQueueDomainSocketChannel ch = new KQueueDomainSocketChannel();
+
+                ctx.writeAndFlush(ch.fd()).addListener(new ChannelFutureListener() {
+                    @Override
+                    public void operationComplete(ChannelFuture future) throws Exception {
+                        if (!future.isSuccess()) {
+                            Throwable cause = future.cause();
+                            queue.offer(cause);
+                        }
+                    }
+                });
+            }
+        });
+        cb.handler(new ChannelInboundHandlerAdapter() {
+            @Override
+            public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {
+                FileDescriptor fd = (FileDescriptor) msg;
+                queue.offer(fd);
+            }
+
+            @Override
+            public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {
+                queue.add(cause);
+                ctx.close();
+            }
+        });
+        cb.option(KQueueChannelOption.DOMAIN_SOCKET_READ_MODE,
+                DomainSocketReadMode.FILE_DESCRIPTORS);
+        Channel sc = sb.bind().sync().channel();
+        Channel cc = cb.connect().sync().channel();
+
+        Object received = queue.take();
+        cc.close().sync();
+        sc.close().sync();
+
+        if (received instanceof FileDescriptor) {
+            FileDescriptor fd = (FileDescriptor) received;
+            Assert.assertTrue(fd.isOpen());
+            fd.close();
+            Assert.assertFalse(fd.isOpen());
+            Assert.assertNull(queue.poll());
+        } else {
+            throw (Throwable) received;
+        }
+    }
+}

transport-native-kqueue/src/test/java/io/netty/channel/kqueue/KQueueDomainSocketFileRegionTest.java

@@ -0,0 +1,35 @@
+/*
+ * Copyright 2016 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache License,
+ * version 2.0 (the "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at:
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+package io.netty.channel.kqueue;
+
+import io.netty.bootstrap.Bootstrap;
+import io.netty.bootstrap.ServerBootstrap;
+import io.netty.testsuite.transport.TestsuitePermutation;
+
+import java.net.SocketAddress;
+import java.util.List;
+
+public class KQueueDomainSocketFileRegionTest extends KQueueSocketFileRegionTest {
+    @Override
+    protected SocketAddress newSocketAddress() {
+        return KQueueSocketTestPermutation.newSocketAddress();
+    }
+
+    @Override
+    protected List<TestsuitePermutation.BootstrapComboFactory<ServerBootstrap, Bootstrap>> newFactories() {
+        return KQueueSocketTestPermutation.INSTANCE.domainSocket();
+    }
+}

transport-native-kqueue/src/test/java/io/netty/channel/kqueue/KQueueDomainSocketFixedLengthEchoTest.java

@@ -0,0 +1,37 @@
+/*
+ * Copyright 2016 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache License,
+ * version 2.0 (the "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at:
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+package io.netty.channel.kqueue;
+
+import io.netty.bootstrap.Bootstrap;
+import io.netty.bootstrap.ServerBootstrap;
+import io.netty.testsuite.transport.TestsuitePermutation;
+import io.netty.testsuite.transport.socket.SocketFixedLengthEchoTest;
+
+import java.net.SocketAddress;
+import java.util.List;
+
+public class KQueueDomainSocketFixedLengthEchoTest extends SocketFixedLengthEchoTest {
+
+    @Override
+    protected SocketAddress newSocketAddress() {
+        return KQueueSocketTestPermutation.newSocketAddress();
+    }
+
+    @Override
+    protected List<TestsuitePermutation.BootstrapComboFactory<ServerBootstrap, Bootstrap>> newFactories() {
+        return KQueueSocketTestPermutation.INSTANCE.domainSocket();
+    }
+}

transport-native-kqueue/src/test/java/io/netty/channel/kqueue/KQueueDomainSocketGatheringWriteTest.java

@@ -0,0 +1,37 @@
+/*
+ * Copyright 2016 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache License,
+ * version 2.0 (the "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at:
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+package io.netty.channel.kqueue;
+
+import io.netty.bootstrap.Bootstrap;
+import io.netty.bootstrap.ServerBootstrap;
+import io.netty.testsuite.transport.TestsuitePermutation;
+import io.netty.testsuite.transport.socket.SocketGatheringWriteTest;
+
+import java.net.SocketAddress;
+import java.util.List;
+
+public class KQueueDomainSocketGatheringWriteTest extends SocketGatheringWriteTest {
+
+    @Override
+    protected SocketAddress newSocketAddress() {
+        return KQueueSocketTestPermutation.newSocketAddress();
+    }
+
+    @Override
+    protected List<TestsuitePermutation.BootstrapComboFactory<ServerBootstrap, Bootstrap>> newFactories() {
+        return KQueueSocketTestPermutation.INSTANCE.domainSocket();
+    }
+}

transport-native-kqueue/src/test/java/io/netty/channel/kqueue/KQueueDomainSocketObjectEchoTest.java

@@ -0,0 +1,36 @@
+/*
+ * Copyright 2016 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache License,
+ * version 2.0 (the "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at:
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+package io.netty.channel.kqueue;
+
+import io.netty.bootstrap.Bootstrap;
+import io.netty.bootstrap.ServerBootstrap;
+import io.netty.testsuite.transport.TestsuitePermutation;
+import io.netty.testsuite.transport.socket.SocketObjectEchoTest;
+
+import java.net.SocketAddress;
+import java.util.List;
+
+public class KQueueDomainSocketObjectEchoTest extends SocketObjectEchoTest {
+    @Override
+    protected SocketAddress newSocketAddress() {
+        return KQueueSocketTestPermutation.newSocketAddress();
+    }
+
+    @Override
+    protected List<TestsuitePermutation.BootstrapComboFactory<ServerBootstrap, Bootstrap>> newFactories() {
+        return KQueueSocketTestPermutation.INSTANCE.domainSocket();
+    }
+}

transport-native-kqueue/src/test/java/io/netty/channel/kqueue/KQueueDomainSocketSslEchoTest.java

@@ -0,0 +1,47 @@
+/*
+ * Copyright 2016 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache License,
+ * version 2.0 (the "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at:
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+package io.netty.channel.kqueue;
+
+import io.netty.bootstrap.Bootstrap;
+import io.netty.bootstrap.ServerBootstrap;
+import io.netty.handler.ssl.SslContext;
+import io.netty.testsuite.transport.TestsuitePermutation;
+import io.netty.testsuite.transport.socket.SocketSslEchoTest;
+
+import java.net.SocketAddress;
+import java.util.List;
+
+public class KQueueDomainSocketSslEchoTest extends SocketSslEchoTest {
+    public KQueueDomainSocketSslEchoTest(
+            SslContext serverCtx, SslContext clientCtx, Renegotiation renegotiation,
+            boolean serverUsesDelegatedTaskExecutor, boolean clientUsesDelegatedTaskExecutor,
+            boolean autoRead, boolean useChunkedWriteHandler, boolean useCompositeByteBuf) {
+
+        super(serverCtx, clientCtx, renegotiation,
+              serverUsesDelegatedTaskExecutor, clientUsesDelegatedTaskExecutor,
+              autoRead, useChunkedWriteHandler, useCompositeByteBuf);
+    }
+
+    @Override
+    protected SocketAddress newSocketAddress() {
+        return KQueueSocketTestPermutation.newSocketAddress();
+    }
+
+    @Override
+    protected List<TestsuitePermutation.BootstrapComboFactory<ServerBootstrap, Bootstrap>> newFactories() {
+        return KQueueSocketTestPermutation.INSTANCE.domainSocket();
+    }
+}

transport-native-kqueue/src/test/java/io/netty/channel/kqueue/KQueueDomainSocketSslGreetingTest.java

@@ -0,0 +1,42 @@
+/*
+ * Copyright 2016 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache License,
+ * version 2.0 (the "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at:
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+package io.netty.channel.kqueue;
+
+import io.netty.bootstrap.Bootstrap;
+import io.netty.bootstrap.ServerBootstrap;
+import io.netty.handler.ssl.SslContext;
+import io.netty.testsuite.transport.TestsuitePermutation;
+import io.netty.testsuite.transport.socket.SocketSslGreetingTest;
+
+import java.net.SocketAddress;
+import java.util.List;
+
+public class KQueueDomainSocketSslGreetingTest extends SocketSslGreetingTest {
+
+    public KQueueDomainSocketSslGreetingTest(SslContext serverCtx, SslContext clientCtx) {
+        super(serverCtx, clientCtx);
+    }
+
+    @Override
+    protected SocketAddress newSocketAddress() {
+        return KQueueSocketTestPermutation.newSocketAddress();
+    }
+
+    @Override
+    protected List<TestsuitePermutation.BootstrapComboFactory<ServerBootstrap, Bootstrap>> newFactories() {
+        return KQueueSocketTestPermutation.INSTANCE.domainSocket();
+    }
+}

transport-native-kqueue/src/test/java/io/netty/channel/kqueue/KQueueDomainSocketStartTlsTest.java

@@ -0,0 +1,42 @@
+/*
+ * Copyright 2016 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache License,
+ * version 2.0 (the "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at:
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+package io.netty.channel.kqueue;
+
+import io.netty.bootstrap.Bootstrap;
+import io.netty.bootstrap.ServerBootstrap;
+import io.netty.handler.ssl.SslContext;
+import io.netty.testsuite.transport.TestsuitePermutation;
+import io.netty.testsuite.transport.socket.SocketStartTlsTest;
+
+import java.net.SocketAddress;
+import java.util.List;
+
+public class KQueueDomainSocketStartTlsTest extends SocketStartTlsTest {
+
+    public KQueueDomainSocketStartTlsTest(SslContext serverCtx, SslContext clientCtx) {
+        super(serverCtx, clientCtx);
+    }
+
+    @Override
+    protected SocketAddress newSocketAddress() {
+        return KQueueSocketTestPermutation.newSocketAddress();
+    }
+
+    @Override
+    protected List<TestsuitePermutation.BootstrapComboFactory<ServerBootstrap, Bootstrap>> newFactories() {
+        return KQueueSocketTestPermutation.INSTANCE.domainSocket();
+    }
+}

transport-native-kqueue/src/test/java/io/netty/channel/kqueue/KQueueDomainSocketStringEchoTest.java

@@ -0,0 +1,36 @@
+/*
+ * Copyright 2016 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache License,
+ * version 2.0 (the "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at:
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+package io.netty.channel.kqueue;
+
+import io.netty.bootstrap.Bootstrap;
+import io.netty.bootstrap.ServerBootstrap;
+import io.netty.testsuite.transport.TestsuitePermutation;
+import io.netty.testsuite.transport.socket.SocketStringEchoTest;
+
+import java.net.SocketAddress;
+import java.util.List;
+
+public class KQueueDomainSocketStringEchoTest extends SocketStringEchoTest {
+    @Override
+    protected SocketAddress newSocketAddress() {
+        return KQueueSocketTestPermutation.newSocketAddress();
+    }
+
+    @Override
+    protected List<TestsuitePermutation.BootstrapComboFactory<ServerBootstrap, Bootstrap>> newFactories() {
+        return KQueueSocketTestPermutation.INSTANCE.domainSocket();
+    }
+}

transport-native-kqueue/src/test/java/io/netty/channel/kqueue/KQueueETSocketAutoReadTest.java

@@ -0,0 +1,31 @@
+/*
+ * Copyright 2016 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache License,
+ * version 2.0 (the "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at:
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+package io.netty.channel.kqueue;
+
+import io.netty.bootstrap.Bootstrap;
+import io.netty.bootstrap.ServerBootstrap;
+import io.netty.buffer.ByteBufAllocator;
+import io.netty.testsuite.transport.TestsuitePermutation;
+import io.netty.testsuite.transport.socket.SocketAutoReadTest;
+
+import java.util.List;
+
+public class KQueueETSocketAutoReadTest extends SocketAutoReadTest {
+    @Override
+    protected List<TestsuitePermutation.BootstrapComboFactory<ServerBootstrap, Bootstrap>> newFactories() {
+        return KQueueSocketTestPermutation.INSTANCE.socket();
+    }
+}

transport-native-kqueue/src/test/java/io/netty/channel/kqueue/KQueueETSocketExceptionHandlingTest.java

@@ -0,0 +1,31 @@
+/*
+ * Copyright 2016 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache License,
+ * version 2.0 (the "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at:
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+package io.netty.channel.kqueue;
+
+import io.netty.bootstrap.Bootstrap;
+import io.netty.bootstrap.ServerBootstrap;
+import io.netty.buffer.ByteBufAllocator;
+import io.netty.testsuite.transport.TestsuitePermutation;
+import io.netty.testsuite.transport.socket.SocketExceptionHandlingTest;
+
+import java.util.List;
+
+public class KQueueETSocketExceptionHandlingTest extends SocketExceptionHandlingTest {
+    @Override
+    protected List<TestsuitePermutation.BootstrapComboFactory<ServerBootstrap, Bootstrap>> newFactories() {
+        return KQueueSocketTestPermutation.INSTANCE.socket();
+    }
+}

transport-native-kqueue/src/test/java/io/netty/channel/kqueue/KQueueETSocketHalfClosedTest.java

@@ -0,0 +1,30 @@
+/*
+ * Copyright 2017 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache License,
+ * version 2.0 (the "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at:
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+package io.netty.channel.kqueue;
+
+import io.netty.bootstrap.Bootstrap;
+import io.netty.bootstrap.ServerBootstrap;
+import io.netty.testsuite.transport.TestsuitePermutation;
+import io.netty.testsuite.transport.socket.SocketHalfClosedTest;
+
+import java.util.List;
+
+public class KQueueETSocketHalfClosedTest extends SocketHalfClosedTest {
+    @Override
+    protected List<TestsuitePermutation.BootstrapComboFactory<ServerBootstrap, Bootstrap>> newFactories() {
+        return KQueueSocketTestPermutation.INSTANCE.socket();
+    }
+}

transport-native-kqueue/src/test/java/io/netty/channel/kqueue/KQueueETSocketReadPendingTest.java

@@ -0,0 +1,31 @@
+/*
+ * Copyright 2016 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache License,
+ * version 2.0 (the "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at:
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+package io.netty.channel.kqueue;
+
+import io.netty.bootstrap.Bootstrap;
+import io.netty.bootstrap.ServerBootstrap;
+import io.netty.buffer.ByteBufAllocator;
+import io.netty.testsuite.transport.TestsuitePermutation;
+import io.netty.testsuite.transport.socket.SocketReadPendingTest;
+
+import java.util.List;
+
+public class KQueueETSocketReadPendingTest extends SocketReadPendingTest {
+    @Override
+    protected List<TestsuitePermutation.BootstrapComboFactory<ServerBootstrap, Bootstrap>> newFactories() {
+        return KQueueSocketTestPermutation.INSTANCE.socket();
+    }
+}

transport-native-kqueue/src/test/java/io/netty/channel/kqueue/KQueueRcvAllocatorOverrideSocketSslEchoTest.java

@@ -0,0 +1,41 @@
+/*
+ * Copyright 2016 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache License,
+ * version 2.0 (the "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at:
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+package io.netty.channel.kqueue;
+
+import io.netty.bootstrap.Bootstrap;
+import io.netty.bootstrap.ServerBootstrap;
+import io.netty.buffer.ByteBufAllocator;
+import io.netty.handler.ssl.SslContext;
+
+public class KQueueRcvAllocatorOverrideSocketSslEchoTest extends KQueueSocketSslEchoTest {
+    public KQueueRcvAllocatorOverrideSocketSslEchoTest(
+            SslContext serverCtx, SslContext clientCtx, Renegotiation renegotiation,
+            boolean serverUsesDelegatedTaskExecutor, boolean clientUsesDelegatedTaskExecutor,
+            boolean autoRead, boolean useChunkedWriteHandler, boolean useCompositeByteBuf) {
+
+        super(serverCtx, clientCtx, renegotiation,
+                serverUsesDelegatedTaskExecutor, clientUsesDelegatedTaskExecutor,
+                autoRead, useChunkedWriteHandler, useCompositeByteBuf);
+    }
+
+    @Override
+    protected void configure(ServerBootstrap bootstrap, Bootstrap bootstrap2, ByteBufAllocator allocator) {
+        super.configure(bootstrap, bootstrap2, allocator);
+        bootstrap.option(KQueueChannelOption.RCV_ALLOC_TRANSPORT_PROVIDES_GUESS, true);
+        bootstrap.childOption(KQueueChannelOption.RCV_ALLOC_TRANSPORT_PROVIDES_GUESS, true);
+        bootstrap2.option(KQueueChannelOption.RCV_ALLOC_TRANSPORT_PROVIDES_GUESS, true);
+    }
+}

transport-native-kqueue/src/test/java/io/netty/channel/kqueue/KQueueServerSocketChannelConfigTest.java

@@ -0,0 +1,82 @@
+/*
+ * Copyright 2016 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache License,
+ * version 2.0 (the "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at:
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+package io.netty.channel.kqueue;
+
+import io.netty.bootstrap.ServerBootstrap;
+import io.netty.channel.ChannelInboundHandlerAdapter;
+import io.netty.channel.EventLoopGroup;
+import org.junit.AfterClass;
+import org.junit.BeforeClass;
+import org.junit.Test;
+
+import java.net.InetSocketAddress;
+
+import static org.hamcrest.Matchers.not;
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertTrue;
+import static org.junit.Assume.assumeThat;
+
+public class KQueueServerSocketChannelConfigTest {
+
+    private static EventLoopGroup group;
+    private static KQueueServerSocketChannel ch;
+
+    @BeforeClass
+    public static void before() {
+        group = new KQueueEventLoopGroup(1);
+        ServerBootstrap bootstrap = new ServerBootstrap();
+        ch = (KQueueServerSocketChannel) bootstrap.group(group)
+                .channel(KQueueServerSocketChannel.class)
+                .childHandler(new ChannelInboundHandlerAdapter())
+                .bind(new InetSocketAddress(0)).syncUninterruptibly().channel();
+    }
+
+    @AfterClass
+    public static void after() {
+        try {
+            ch.close().syncUninterruptibly();
+        } finally {
+            group.shutdownGracefully();
+        }
+    }
+
+    @Test
+    public void testReusePort() {
+        ch.config().setReusePort(false);
+        assertFalse(ch.config().isReusePort());
+        ch.config().setReusePort(true);
+        assertTrue(ch.config().isReusePort());
+    }
+
+    @Test
+    public void testAcceptFilter() {
+        AcceptFilter currentFilter = ch.config().getAcceptFilter();
+        // Not all platforms support this option (e.g. MacOS doesn't) so test if we support the option first.
+        assumeThat(currentFilter, not(AcceptFilter.PLATFORM_UNSUPPORTED));
+
+        AcceptFilter af = new AcceptFilter("test", "foo");
+        ch.config().setAcceptFilter(af);
+        assertEquals(af, ch.config().getAcceptFilter());
+    }
+
+    @Test
+    public void testOptionsDoesNotThrow() {
+        // If there are some options that are not fully supported they shouldn't throw but instead return some "default"
+        // object.
+        assertFalse(ch.config().getOptions().isEmpty());
+    }
+}

transport-native-kqueue/src/test/java/io/netty/channel/kqueue/KQueueSocketChannelConfigTest.java

@@ -0,0 +1,125 @@
+/*
+ * Copyright 2015 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache License,
+ * version 2.0 (the "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at:
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+package io.netty.channel.kqueue;
+
+import io.netty.bootstrap.Bootstrap;
+import io.netty.channel.ChannelException;
+import io.netty.channel.ChannelInboundHandlerAdapter;
+import io.netty.channel.EventLoopGroup;
+import org.junit.After;
+import org.junit.AfterClass;
+import org.junit.Before;
+import org.junit.BeforeClass;
+import org.junit.Test;
+
+import java.net.InetSocketAddress;
+import java.nio.channels.ClosedChannelException;
+import java.util.Random;
+
+import static io.netty.channel.kqueue.BsdSocket.BSD_SND_LOW_AT_MAX;
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.fail;
+import static org.junit.Assume.assumeNoException;
+
+public class KQueueSocketChannelConfigTest {
+
+    private static EventLoopGroup group;
+    private static KQueueSocketChannel ch;
+    private static Random rand;
+
+    @BeforeClass
+    public static void beforeClass() {
+        rand = new Random();
+        group = new KQueueEventLoopGroup(1);
+    }
+
+    @AfterClass
+    public static void afterClass() {
+        group.shutdownGracefully();
+    }
+
+    @Before
+    public void setup() {
+        Bootstrap bootstrap = new Bootstrap();
+        ch = (KQueueSocketChannel) bootstrap.group(group)
+                .channel(KQueueSocketChannel.class)
+                .handler(new ChannelInboundHandlerAdapter())
+                .bind(new InetSocketAddress(0)).syncUninterruptibly().channel();
+    }
+
+    @After
+    public void teardown() {
+        ch.close().syncUninterruptibly();
+    }
+
+    @Test
+    public void testRandomSndLowAt() {
+        final int expected = Math.min(BSD_SND_LOW_AT_MAX, Math.abs(rand.nextInt()));
+        final int actual;
+        try {
+            ch.config().setSndLowAt(expected);
+            actual = ch.config().getSndLowAt();
+        } catch (RuntimeException e) {
+            assumeNoException(e);
+            return; // Needed to prevent compile error for final variables to be used below
+        }
+        assertEquals(expected, actual);
+    }
+
+    @Test
+    public void testInvalidHighSndLowAt() {
+        try {
+            ch.config().setSndLowAt(Integer.MIN_VALUE);
+        } catch (ChannelException e) {
+            return;
+        } catch (RuntimeException e) {
+            assumeNoException(e);
+        }
+        fail();
+    }
+
+    @Test
+    public void testTcpNoPush() {
+        ch.config().setTcpNoPush(false);
+        assertFalse(ch.config().isTcpNoPush());
+        ch.config().setTcpNoPush(true);
+        assertTrue(ch.config().isTcpNoPush());
+    }
+
+    @Test
+    public void testSetOptionWhenClosed() {
+        ch.close().syncUninterruptibly();
+        try {
+            ch.config().setSoLinger(0);
+            fail();
+        } catch (ChannelException e) {
+            assertTrue(e.getCause() instanceof ClosedChannelException);
+        }
+    }
+
+    @Test
+    public void testGetOptionWhenClosed() {
+        ch.close().syncUninterruptibly();
+        try {
+        ch.config().getSoLinger();
+            fail();
+        } catch (ChannelException e) {
+            assertTrue(e.getCause() instanceof ClosedChannelException);
+        }
+    }
+}

transport-native-kqueue/src/test/java/io/netty/channel/kqueue/KQueueSocketChannelNotYetConnectedTest.java

@@ -0,0 +1,29 @@
+/*
+ * Copyright 2016 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache License,
+ * version 2.0 (the "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at:
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+package io.netty.channel.kqueue;
+
+import io.netty.bootstrap.Bootstrap;
+import io.netty.testsuite.transport.TestsuitePermutation;
+import io.netty.testsuite.transport.socket.SocketChannelNotYetConnectedTest;
+
+import java.util.List;
+
+public class KQueueSocketChannelNotYetConnectedTest extends SocketChannelNotYetConnectedTest {
+    @Override
+    protected List<TestsuitePermutation.BootstrapFactory<Bootstrap>> newFactories() {
+        return KQueueSocketTestPermutation.INSTANCE.clientSocket();
+    }
+}

transport-native-kqueue/src/test/java/io/netty/channel/kqueue/KQueueSocketConnectTest.java

@@ -0,0 +1,31 @@
+/*
+ * Copyright 2016 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache License,
+ * version 2.0 (the "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at:
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+package io.netty.channel.kqueue;
+
+import io.netty.bootstrap.Bootstrap;
+import io.netty.bootstrap.ServerBootstrap;
+import io.netty.testsuite.transport.TestsuitePermutation;
+import io.netty.testsuite.transport.socket.SocketConnectTest;
+
+import java.util.List;
+
+public class KQueueSocketConnectTest extends SocketConnectTest {
+
+    @Override
+    protected List<TestsuitePermutation.BootstrapComboFactory<ServerBootstrap, Bootstrap>> newFactories() {
+        return KQueueSocketTestPermutation.INSTANCE.socket();
+    }
+}

transport-native-kqueue/src/test/java/io/netty/channel/kqueue/KQueueSocketConnectionAttemptTest.java

@@ -0,0 +1,33 @@
+/*
+ * Copyright 2016 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache License,
+ * version 2.0 (the "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at:
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+package io.netty.channel.kqueue;
+
+import io.netty.bootstrap.Bootstrap;
+import io.netty.channel.Channel;
+import io.netty.channel.ChannelInitializer;
+import io.netty.testsuite.transport.TestsuitePermutation;
+import io.netty.testsuite.transport.socket.SocketConnectionAttemptTest;
+import org.junit.Test;
+
+import java.net.InetSocketAddress;
+import java.util.List;
+
+public class KQueueSocketConnectionAttemptTest extends SocketConnectionAttemptTest {
+    @Override
+    protected List<TestsuitePermutation.BootstrapFactory<Bootstrap>> newFactories() {
+        return KQueueSocketTestPermutation.INSTANCE.clientSocket();
+    }
+}

transport-native-kqueue/src/test/java/io/netty/channel/kqueue/KQueueSocketEchoTest.java

@@ -0,0 +1,31 @@
+/*
+ * Copyright 2016 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache License,
+ * version 2.0 (the "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at:
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+package io.netty.channel.kqueue;
+
+import io.netty.bootstrap.Bootstrap;
+import io.netty.bootstrap.ServerBootstrap;
+import io.netty.testsuite.transport.TestsuitePermutation;
+import io.netty.testsuite.transport.socket.SocketEchoTest;
+
+import java.util.List;
+
+public class KQueueSocketEchoTest extends SocketEchoTest {
+
+    @Override
+    protected List<TestsuitePermutation.BootstrapComboFactory<ServerBootstrap, Bootstrap>> newFactories() {
+        return KQueueSocketTestPermutation.INSTANCE.socket();
+    }
+}

transport-native-kqueue/src/test/java/io/netty/channel/kqueue/KQueueSocketFileRegionTest.java

@@ -0,0 +1,31 @@
+/*
+ * Copyright 2016 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache License,
+ * version 2.0 (the "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at:
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+package io.netty.channel.kqueue;
+
+import io.netty.bootstrap.Bootstrap;
+import io.netty.bootstrap.ServerBootstrap;
+import io.netty.testsuite.transport.TestsuitePermutation;
+import io.netty.testsuite.transport.socket.SocketFileRegionTest;
+
+import java.util.List;
+
+public class KQueueSocketFileRegionTest extends SocketFileRegionTest {
+
+    @Override
+    protected List<TestsuitePermutation.BootstrapComboFactory<ServerBootstrap, Bootstrap>> newFactories() {
+        return KQueueSocketTestPermutation.INSTANCE.socket();
+    }
+}

transport-native-kqueue/src/test/java/io/netty/channel/kqueue/KQueueSocketFixedLengthEchoTest.java

@@ -0,0 +1,31 @@
+/*
+ * Copyright 2016 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache License,
+ * version 2.0 (the "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at:
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+package io.netty.channel.kqueue;
+
+import io.netty.bootstrap.Bootstrap;
+import io.netty.bootstrap.ServerBootstrap;
+import io.netty.testsuite.transport.TestsuitePermutation;
+import io.netty.testsuite.transport.socket.SocketFixedLengthEchoTest;
+
+import java.util.List;
+
+public class KQueueSocketFixedLengthEchoTest extends SocketFixedLengthEchoTest {
+
+    @Override
+    protected List<TestsuitePermutation.BootstrapComboFactory<ServerBootstrap, Bootstrap>> newFactories() {
+        return KQueueSocketTestPermutation.INSTANCE.socket();
+    }
+}

transport-native-kqueue/src/test/java/io/netty/channel/kqueue/KQueueSocketGatheringWriteTest.java

@@ -0,0 +1,31 @@
+/*
+ * Copyright 2016 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache License,
+ * version 2.0 (the "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at:
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+package io.netty.channel.kqueue;
+
+import io.netty.bootstrap.Bootstrap;
+import io.netty.bootstrap.ServerBootstrap;
+import io.netty.testsuite.transport.TestsuitePermutation;
+import io.netty.testsuite.transport.socket.SocketGatheringWriteTest;
+
+import java.util.List;
+
+public class KQueueSocketGatheringWriteTest extends SocketGatheringWriteTest {
+
+    @Override
+    protected List<TestsuitePermutation.BootstrapComboFactory<ServerBootstrap, Bootstrap>> newFactories() {
+        return KQueueSocketTestPermutation.INSTANCE.socket();
+    }
+}

transport-native-kqueue/src/test/java/io/netty/channel/kqueue/KQueueSocketMultipleConnectTest.java

@@ -0,0 +1,42 @@
+/*
+ * Copyright 2016 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache License,
+ * version 2.0 (the "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at:
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+package io.netty.channel.kqueue;
+
+import io.netty.bootstrap.Bootstrap;
+import io.netty.bootstrap.ServerBootstrap;
+import io.netty.channel.EventLoopGroup;
+import io.netty.channel.nio.NioEventLoopGroup;
+import io.netty.testsuite.transport.TestsuitePermutation;
+import io.netty.testsuite.transport.socket.SocketMultipleConnectTest;
+
+import java.util.ArrayList;
+import java.util.List;
+
+public class KQueueSocketMultipleConnectTest extends SocketMultipleConnectTest {
+    @Override
+    protected List<TestsuitePermutation.BootstrapComboFactory<ServerBootstrap, Bootstrap>> newFactories() {
+        List<TestsuitePermutation.BootstrapComboFactory<ServerBootstrap, Bootstrap>> factories
+                = new ArrayList<TestsuitePermutation.BootstrapComboFactory<ServerBootstrap, Bootstrap>>();
+        for (TestsuitePermutation.BootstrapComboFactory<ServerBootstrap, Bootstrap> comboFactory
+                : KQueueSocketTestPermutation.INSTANCE.socket()) {
+            EventLoopGroup group = comboFactory.newClientInstance().config().group();
+            if (group instanceof NioEventLoopGroup || group instanceof KQueueEventLoopGroup) {
+                factories.add(comboFactory);
+            }
+        }
+        return factories;
+    }
+}

transport-native-kqueue/src/test/java/io/netty/channel/kqueue/KQueueSocketObjectEchoTest.java

@@ -0,0 +1,31 @@
+/*
+ * Copyright 2016 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache License,
+ * version 2.0 (the "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at:
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+package io.netty.channel.kqueue;
+
+import io.netty.bootstrap.Bootstrap;
+import io.netty.bootstrap.ServerBootstrap;
+import io.netty.testsuite.transport.TestsuitePermutation;
+import io.netty.testsuite.transport.socket.SocketObjectEchoTest;
+
+import java.util.List;
+
+public class KQueueSocketObjectEchoTest extends SocketObjectEchoTest {
+
+    @Override
+    protected List<TestsuitePermutation.BootstrapComboFactory<ServerBootstrap, Bootstrap>> newFactories() {
+        return KQueueSocketTestPermutation.INSTANCE.socket();
+    }
+}