Cleanup

Motivation:

fix checkstyle errors and many classes are unnecessarily public

Modification:
-fixed maven checkstyle errors
-using package-private and final classes

Result:
better code quality

example/pom.xml

@@ -43,7 +43,6 @@
       <artifactId>netty-buffer</artifactId>
       <version>${project.version}</version>
     </dependency>
-
     <dependency>
       <groupId>${project.groupId}</groupId>
       <artifactId>netty-transport-native-io_uring</artifactId>

run-example.sh

@@ -1,6 +1,6 @@
 #!/bin/bash -e
 EXAMPLE_MAP=(
-  'uring:io.netty.example.uring.EchoIOUringServer'
+  'io_uring:io.netty.example.uring.EchoIOUringServer'
   'discard-client:io.netty.example.discard.DiscardClient'
   'discard-server:io.netty.example.discard.DiscardServer'
   'echo-client:io.netty.example.echo.EchoClient'

transport-native-io_uring/src/main/c/io_uring.h

@@ -17,13 +17,16 @@
 #include <stddef.h>
 #include <stdint.h>
 #include <stdio.h>
+#include "netty_unix_buffer.h"
 #include "netty_unix_errors.h"
 #include "netty_unix_filedescriptor.h"
 #include "netty_unix_jni.h"
+#include "netty_unix_limits.h"
 #include "netty_unix_socket.h"
 #include "netty_unix_util.h"
-#ifndef LIB_TEST
-#define LIB_TEST
+
+#ifndef NETTY_IO_URING
+#define NETTY_IO_URING
 
 struct io_uring_sq {
     unsigned *khead;

transport-native-io_uring/src/main/c/netty_io_uring_native.c

@@ -56,14 +56,6 @@
 #include <sys/stat.h>
 #include <sys/types.h>
 
-#include "netty_unix_buffer.h"
-#include "netty_unix_errors.h"
-#include "netty_unix_filedescriptor.h"
-#include "netty_unix_jni.h"
-#include "netty_unix_limits.h"
-#include "netty_unix_socket.h"
-#include "netty_unix_util.h"
-
 static jmethodID ringBufferMethodId = NULL;
 static jmethodID ioUringSubmissionQueueMethodId = NULL;
 static jmethodID ioUringCommpletionQueueMethodId = NULL;
@@ -73,12 +65,14 @@ static jclass ioUringSubmissionQueueClass = NULL;
 
 void io_uring_unmap_rings(struct io_uring_sq *sq, struct io_uring_cq *cq) {
     munmap(sq->ring_ptr, sq->ring_sz);
-  if (cq->ring_ptr && cq->ring_ptr != sq->ring_ptr)
+    if (cq->ring_ptr && cq->ring_ptr != sq->ring_ptr) {
         munmap(cq->ring_ptr, cq->ring_sz);
+  }
 }
 
-int io_uring_mmap(int fd, struct io_uring_params *p, struct io_uring_sq *sq,
-                  struct io_uring_cq *cq) {
+static int io_uring_mmap(int fd, struct io_uring_params *p,
+			 struct io_uring_sq *sq, struct io_uring_cq *cq)
+{
 	size_t size;
 	int ret;
 
@@ -116,13 +110,12 @@ int io_uring_mmap(int fd, struct io_uring_params *p, struct io_uring_sq *sq,
 	sq->array = sq->ring_ptr + p->sq_off.array;
 
 	size = p->sq_entries * sizeof(struct io_uring_sqe);
-  sq->sqes = mmap(0, size, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_POPULATE,
-                  fd, IORING_OFF_SQES);
+	sq->sqes = mmap(0, size, PROT_READ | PROT_WRITE,
+				MAP_SHARED | MAP_POPULATE, fd,
+				IORING_OFF_SQES);
 	if (sq->sqes == MAP_FAILED) {
 		ret = -errno;
-  err:
-    io_uring_unmap_rings(sq, cq);
-    return ret;
+		goto err;
 	}
 
 	cq->khead = cq->ring_ptr + p->cq_off.head;
@@ -131,7 +124,11 @@ int io_uring_mmap(int fd, struct io_uring_params *p, struct io_uring_sq *sq,
 	cq->kring_entries = cq->ring_ptr + p->cq_off.ring_entries;
 	cq->koverflow = cq->ring_ptr + p->cq_off.overflow;
 	cq->cqes = cq->ring_ptr + p->cq_off.cqes;
+
 	return 0;
+err:
+	io_uring_unmap_rings(sq, cq);
+	return ret;
 }
 
 void setup_io_uring(int ring_fd, struct io_uring *io_uring_ring,
@@ -143,6 +140,7 @@ void setup_io_uring(int ring_fd, struct io_uring *io_uring_ring,
         io_uring_ring->flags = p->flags;
         io_uring_ring->ring_fd = ring_fd;
     } else {
+        //Todo signal this back to EventLoop
         perror("setup_io_uring error \n");
     }
 }
@@ -152,6 +150,10 @@ static jint netty_io_uring_enter(JNIEnv *env, jclass class1, jint ring_fd, jint
     return sys_io_uring_enter(ring_fd, to_submit, min_complete, flags, NULL);
 }
 
+static int nettyBlockingSocket(int domain, int type, int protocol) {
+    return socket(domain, type, protocol);
+}
+
 static jobject netty_io_uring_setup(JNIEnv *env, jclass class1, jint entries) {
     struct io_uring_params p;
     memset(&p, 0, sizeof(p));
@@ -163,15 +165,13 @@ static jobject netty_io_uring_setup(JNIEnv *env, jclass class1, jint entries) {
       //throw Exception
       return NULL;
     }
-
     struct io_uring io_uring_ring;
-  //memset instead
+    //Todo memset instead
     io_uring_ring.flags = 0;
     io_uring_ring.sq.sqe_tail = 0;
     io_uring_ring.sq.sqe_head = 0;
     setup_io_uring(ring_fd, &io_uring_ring, &p);
 
-
     jobject ioUringSubmissionQueue = (*env)->NewObject(
         env, ioUringSubmissionQueueClass, ioUringSubmissionQueueMethodId,
         (jlong)io_uring_ring.sq.khead, (jlong)io_uring_ring.sq.ktail,
@@ -197,19 +197,18 @@ static jobject netty_io_uring_setup(JNIEnv *env, jclass class1, jint entries) {
     return ringBuffer;
 }
 
-static jlong netty_create_file(JNIEnv *env, jclass class) {
+static jint netty_create_file(JNIEnv *env, jclass class) {
     return open("io-uring-test.txt", O_RDWR | O_TRUNC | O_CREAT, 0644);
 }
 
 static void netty_io_uring_native_JNI_OnUnLoad(JNIEnv *env) {
-  // OnUnLoad
+    // Todo OnUnLoad
 }
 
 // JNI Method Registration Table Begin
 static const JNINativeMethod method_table[] = {
-    {"ioUringSetup", "(I)Lio/netty/channel/uring/RingBuffer;",
-     (void *)netty_io_uring_setup},
-    {"createFile", "()J", (void *)netty_create_file},
+    {"ioUringSetup", "(I)Lio/netty/channel/uring/RingBuffer;", (void *)netty_io_uring_setup},
+    {"createFile", "()I", (void *)netty_create_file},
     {"ioUringEnter", "(IIII)I", (void *)netty_io_uring_enter}};
 static const jint method_table_size =
     sizeof(method_table) / sizeof(method_table[0]);
@@ -291,7 +290,7 @@ JNIEXPORT jint JNI_OnLoad(JavaVM *vm, void *reserved) {
                    ioUringCommpletionQueueMethodId, "<init>", "(JJJJJJIJI)V",
                    done);
 
-done:
+    done:
     //unload
 
     return NETTY_JNI_VERSION;

transport-native-io_uring/src/main/c/syscall.c

@@ -19,11 +19,6 @@
 #include <sys/uio.h>
 #include <unistd.h>
 
-int sys_io_uring_register(int fd, unsigned opcode, const void *arg,
-                          unsigned nr_args) {
-  return syscall(__NR_io_uring_register, fd, opcode, arg, nr_args);
-}
-
 int sys_io_uring_setup(unsigned entries, struct io_uring_params *p) {
     return syscall(__NR_io_uring_setup, entries, p);
 }

transport-native-io_uring/src/main/c/syscall.h

@@ -24,7 +24,5 @@
 extern int sys_io_uring_setup(unsigned entries, struct io_uring_params *p);
 extern int sys_io_uring_enter(int fd, unsigned to_submit, unsigned min_complete,
                               unsigned flags, sigset_t *sig);
-extern int sys_io_uring_register(int fd, unsigned int opcode, const void *arg,
-                                 unsigned int nr_args);
 
 #endif

transport-native-io_uring/src/main/java/io/netty/channel/uring/AbstractIOUringChannel.java

@@ -151,7 +151,7 @@ abstract class AbstractIOUringChannel extends AbstractChannel implements UnixCha
 
     // Channel/ChannelHandlerContext.read() was called
     @Override
-    protected void doBeginRead() throws Exception {
+    protected void doBeginRead() {
         final AbstractUringUnsafe unsafe = (AbstractUringUnsafe) unsafe();
         if (!uringInReadyPending) {
             uringInReadyPending = true;

transport-native-io_uring/src/main/java/io/netty/channel/uring/IOUringCompletionQueue.java

@@ -17,7 +17,7 @@ package io.netty.channel.uring;
 
 import io.netty.util.internal.PlatformDependent;
 
-public class IOUringCompletionQueue {
+final class IOUringCompletionQueue {
 
   //these offsets are used to access specific properties
   //CQE (https://github.com/axboe/liburing/blob/master/src/include/liburing/io_uring.h#L162)
@@ -42,7 +42,7 @@ public class IOUringCompletionQueue {
   private final long ringAddress;
   private final int ringFd;
 
-  public IOUringCompletionQueue(long kHeadAddress, long kTailAddress, long kringMaskAddress, long kringEntries,
+  IOUringCompletionQueue(long kHeadAddress, long kTailAddress, long kringMaskAddress, long kringEntries,
       long kOverflowAddress, long completionQueueArrayAddress, int ringSize, long ringAddress, int ringFd) {
     this.kHeadAddress = kHeadAddress;
     this.kTailAddress = kTailAddress;

transport-native-io_uring/src/main/java/io/netty/channel/uring/IOUringCqe.java

@@ -15,7 +15,7 @@
  */
 package io.netty.channel.uring;
 
-class IOUringCqe {
+final class IOUringCqe {
     private final long eventId;
     private final int res;
     private final long flags;

transport-native-io_uring/src/main/java/io/netty/channel/uring/IOUringEventLoop.java

@@ -25,14 +25,14 @@ import java.util.concurrent.Executor;
 
 import static io.netty.channel.unix.Errors.*;
 
-class IOUringEventLoop extends SingleThreadEventLoop {
+final class IOUringEventLoop extends SingleThreadEventLoop {
 
     // events should be unique to identify which event type that was
     private long eventIdCounter;
     private final LongObjectHashMap<Event> events = new LongObjectHashMap<Event>();
     private RingBuffer ringBuffer;
 
-    protected IOUringEventLoop(final EventLoopGroup parent, final Executor executor, final boolean addTaskWakesUp) {
+    IOUringEventLoop(final EventLoopGroup parent, final Executor executor, final boolean addTaskWakesUp) {
         super(parent, executor, addTaskWakesUp);
         ringBuffer = Native.createRingBuffer(32);
     }

transport-native-io_uring/src/main/java/io/netty/channel/uring/IOUringServerChannelConfig.java

@@ -33,7 +33,6 @@ import static io.netty.util.internal.ObjectUtil.*;
 
 public class IOUringServerChannelConfig extends IOUringChannelConfig implements ServerSocketChannelConfig {
     private volatile int backlog = NetUtil.SOMAXCONN;
-    private volatile int pendingFastOpenRequestsThreshold;
 
     IOUringServerChannelConfig(AbstractIOUringServerChannel channel) {
         super(channel);

transport-native-io_uring/src/main/java/io/netty/channel/uring/IOUringServerSocketChannel.java

@@ -23,7 +23,7 @@ import io.netty.channel.unix.Socket;
 import java.net.InetSocketAddress;
 import java.net.SocketAddress;
 
-public class IOUringServerSocketChannel extends AbstractIOUringServerChannel implements ServerSocketChannel {
+public final class IOUringServerSocketChannel extends AbstractIOUringServerChannel implements ServerSocketChannel {
     private final IOUringServerSocketChannelConfig config;
 
     public IOUringServerSocketChannel() {

transport-native-io_uring/src/main/java/io/netty/channel/uring/IOUringSocketChannel.java

@@ -32,7 +32,7 @@ import io.netty.channel.unix.FileDescriptor;
 import java.net.InetSocketAddress;
 import java.net.SocketAddress;
 
-public class IOUringSocketChannel extends AbstractIOUringChannel implements SocketChannel {
+public final class IOUringSocketChannel extends AbstractIOUringChannel implements SocketChannel {
     private final IOUringSocketChannelConfig config;
 
     IOUringSocketChannel(final Channel parent, final LinuxSocket fd) {

transport-native-io_uring/src/main/java/io/netty/channel/uring/IOUringSubmissionQueue.java

@@ -17,7 +17,7 @@ package io.netty.channel.uring;
 
 import io.netty.util.internal.PlatformDependent;
 
-public class IOUringSubmissionQueue {
+final class IOUringSubmissionQueue {
 
     private static final int SQE_SIZE = 64;
     private static final int INT_SIZE = Integer.BYTES; //no 32 Bit support?
@@ -53,7 +53,7 @@ public class IOUringSubmissionQueue {
     private final long ringAddress;
     private final int ringFd;
 
-    public IOUringSubmissionQueue(long kHeadAddress, long kTailAddress, long kRingMaskAddress, long kRingEntriesAddress,
+    IOUringSubmissionQueue(long kHeadAddress, long kTailAddress, long kRingMaskAddress, long kRingEntriesAddress,
                                   long fFlagsAdress, long kDroppedAddress, long arrayAddress,
                                   long submissionQueueArrayAddress, int ringSize,
                                   long ringAddress, int ringFd) {

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

@@ -17,10 +17,10 @@ package io.netty.channel.uring;
 
 import io.netty.channel.unix.Socket;
 
-public class LinuxSocket extends Socket {
+final class LinuxSocket extends Socket {
     private final int fd;
 
-    public LinuxSocket(final int fd) {
+    LinuxSocket(final int fd) {
         super(fd);
         this.fd = fd;
     }

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

@@ -15,19 +15,14 @@
  */
 package io.netty.channel.uring;
 
-import io.netty.channel.unix.FileDescriptor;
 import io.netty.channel.unix.Socket;
 import io.netty.util.internal.NativeLibraryLoader;
 import io.netty.util.internal.PlatformDependent;
 import io.netty.util.internal.SystemPropertyUtil;
 import io.netty.util.internal.ThrowableUtil;
-import io.netty.util.internal.logging.InternalLogger;
-import io.netty.util.internal.logging.InternalLoggerFactory;
-
-import java.io.IOException;
 import java.util.Locale;
 
-public final class Native {
+final class Native {
 
     private static final int DEFAULT_RING_SIZE = SystemPropertyUtil.getInt("io.netty.uring.ringSize", 32);
     static {
@@ -50,7 +45,7 @@ public final class Native {
     public static native int ioUringEnter(int ringFd, int toSubmit, int minComplete, int flags);
 
     // for testing(it is only temporary)
-    public static native long createFile();
+    public static native int createFile();
 
     private Native() {
         // utility

transport-native-io_uring/src/main/java/io/netty/channel/uring/RingBuffer.java

@@ -16,7 +16,7 @@
 package io.netty.channel.uring;
 
 
-class RingBuffer {
+final class RingBuffer {
   private final IOUringSubmissionQueue ioUringSubmissionQueue;
   private final IOUringCompletionQueue ioUringCompletionQueue;
 

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

@@ -14,6 +14,7 @@
  * under the License.
  */
 /**
- * io_uring
+ * io_uring is a high I/O performance scalable interface for fully
+ * asynchronous Linux syscalls <a href="https://kernel.dk/io_uring.pdf">io_uring doc</a>
  */
 package io.netty.channel.uring;

transport-native-io_uring/src/test/java/io/netty/channel/uring/NativeTest.java

@@ -15,16 +15,10 @@
  */
 package io.netty.channel.uring;
 
-import io.netty.channel.unix.Socket;
 import org.junit.Test;
-
-import java.io.FileInputStream;
-
-import java.io.File;
-
+import java.nio.charset.Charset;
 import io.netty.buffer.ByteBufAllocator;
 import io.netty.buffer.UnpooledByteBufAllocator;
-import io.netty.buffer.UnpooledUnsafeDirectByteBuf;
 import static org.junit.Assert.*;
 import io.netty.buffer.ByteBuf;
 
@@ -37,8 +31,7 @@ public class NativeTest {
         ByteBufAllocator allocator = new UnpooledByteBufAllocator(true);
         ByteBuf writeEventByteBuf = allocator.directBuffer(100);
         String inputString = "Hello World!";
-        byte[] byteArrray = inputString.getBytes();
-        writeEventByteBuf.writeBytes(byteArrray);
+        writeEventByteBuf.writeCharSequence(inputString, Charset.forName("UTF-8"));
 
         int fd = (int) Native.createFile();
 
@@ -73,7 +66,7 @@ public class NativeTest {
         byte[] dataRead = new byte[inputString.length()];
         readEventByteBuf.readBytes(dataRead);
 
-        assertEquals(inputString, new String(dataRead));
+        assertArrayEquals(inputString.getBytes(), dataRead);
         readEventByteBuf.release();
     }
 }

transport-native-unix-common/src/main/java/io/netty/channel/unix/FileDescriptor.java

@@ -201,6 +201,7 @@ public class FileDescriptor {
     }
 
     static boolean isClosed(int state) {
+        System.out.println("State: " + state);
         return (state & STATE_CLOSED_MASK) != 0;
     }