From 076c35f7852ac9d7593ccffc9cf889a78ecc5e6c Mon Sep 17 00:00:00 2001
From: Norman Maurer <norman_maurer@apple.com>
Date: Sun, 30 Aug 2020 21:13:52 +0200
Subject: [PATCH] Fallback to simple write when we can not allocate iovec array
 and correctly handle poll mask

---
 .../channel/uring/AbstractIOUringChannel.java |  7 ++++--
 .../netty/channel/uring/IOUringEventLoop.java | 22 +++++++++----------
 2 files changed, 15 insertions(+), 14 deletions(-)

diff --git a/transport-native-io_uring/src/main/java/io/netty/channel/uring/AbstractIOUringChannel.java b/transport-native-io_uring/src/main/java/io/netty/channel/uring/AbstractIOUringChannel.java
index 383903d9d9..58a177f26b 100644
--- a/transport-native-io_uring/src/main/java/io/netty/channel/uring/AbstractIOUringChannel.java
+++ b/transport-native-io_uring/src/main/java/io/netty/channel/uring/AbstractIOUringChannel.java
@@ -290,7 +290,8 @@ abstract class AbstractIOUringChannel extends AbstractChannel implements UnixCha
              try {
                  in.forEachFlushedMessage(iovecArray);
              } catch (Exception e) {
-
+                 // This should never happem, anyway fallback to single write.
+                 doWriteSingle((ByteBuf) in.current());
              }
 
              if (iovecArray.count() > 0) {
@@ -298,8 +299,10 @@ abstract class AbstractIOUringChannel extends AbstractChannel implements UnixCha
                  submissionQueue().submit();
                  writeScheduled = true;
              }
+         } else {
+             // We were not be able to create a new iovec, fallback to single write.
+             doWriteSingle((ByteBuf) in.current());
          }
-         //Todo error handling
      }
 
 
diff --git a/transport-native-io_uring/src/main/java/io/netty/channel/uring/IOUringEventLoop.java b/transport-native-io_uring/src/main/java/io/netty/channel/uring/IOUringEventLoop.java
index 2ce47f8123..0f2405ce6f 100644
--- a/transport-native-io_uring/src/main/java/io/netty/channel/uring/IOUringEventLoop.java
+++ b/transport-native-io_uring/src/main/java/io/netty/channel/uring/IOUringEventLoop.java
@@ -192,6 +192,8 @@ final class IOUringEventLoop extends SingleThreadEventLoop implements
                 ((AbstractIOUringChannel.AbstractUringUnsafe) readChannel.unsafe()).readComplete(res);
                 break;
             case IOUring.OP_WRITEV:
+                // Fall-through
+
             case IOUring.OP_WRITE:
                 AbstractIOUringChannel writeChannel = channels.get(fd);
                 if (writeChannel == null) {
@@ -219,18 +221,14 @@ final class IOUringEventLoop extends SingleThreadEventLoop implements
                     if (channel == null) {
                         break;
                     }
-                    switch (pollMask) {
-                        case IOUring.POLLMASK_IN:
-                            ((AbstractIOUringChannel.AbstractUringUnsafe) channel.unsafe()).pollIn(res);
-                            break;
-                        case IOUring.POLLMASK_OUT:
-                            ((AbstractIOUringChannel.AbstractUringUnsafe) channel.unsafe()).pollOut(res);
-                            break;
-                        case IOUring.POLLMASK_RDHUP:
-                            ((AbstractIOUringChannel.AbstractUringUnsafe) channel.unsafe()).pollRdHup(res);
-                            break;
-                        default:
-                            break;
+                    if ((pollMask & IOUring.POLLMASK_OUT) != 0) {
+                        ((AbstractIOUringChannel.AbstractUringUnsafe) channel.unsafe()).pollOut(res);
+                    }
+                    if ((pollMask & IOUring.POLLMASK_IN) != 0) {
+                        ((AbstractIOUringChannel.AbstractUringUnsafe) channel.unsafe()).pollIn(res);
+                    }
+                    if ((pollMask & IOUring.POLLMASK_RDHUP) != 0) {
+                        ((AbstractIOUringChannel.AbstractUringUnsafe) channel.unsafe()).pollRdHup(res);
                     }
                 }
                 break;