Handle single EPOLLHUP epoll events on Linux.

runtime/bin/eventhandler_linux.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "platform/globals.h"
 #if defined(TARGET_OS_LINUX)
 
 #include "bin/eventhandler.h"
 
 #include <errno.h>  // NOLINT
@@ skipping 247 matching lines @@
     // For listening sockets the EPOLLIN event indicate that there are
     // connections ready for accept unless accompanied with one of the
     // other flags.
     if ((events & EPOLLIN) != 0) {
       if ((events & EPOLLHUP) != 0) event_mask |= (1 << kCloseEvent);
       if ((events & EPOLLERR) != 0) event_mask |= (1 << kErrorEvent);
       if (event_mask == 0) event_mask |= (1 << kInEvent);
     }
   } else {
     // Prioritize data events over close and error events.
-    if ((events & EPOLLIN) != 0) {
-      if (FDUtils::AvailableBytes(sd->fd()) != 0) {
+    if ((events & (EPOLLIN | EPOLLHUP | EPOLLERR)) != 0) {
+      // If we have EPOLLIN and we have available writes, report that.

[Søren Gjesse, 2013/02/22 11:41:20]

writes -> bytes

[Anders Johnsen, 2013/02/22 11:42:19]

Done.

+      if ((events & EPOLLIN) && FDUtils::AvailableBytes(sd->fd()) != 0) {
         event_mask = (1 << kInEvent);
       } else if ((events & EPOLLHUP) != 0) {
         // If both EPOLLHUP and EPOLLERR are reported treat it as an
         // error.
         if ((events & EPOLLERR) != 0) {
           event_mask = (1 << kErrorEvent);
         } else {
           event_mask = (1 << kCloseEvent);
         }
         sd->MarkClosedRead();
@@ skipping 19 matching lines @@
           if (bytesPeeked == 0) {
             event_mask = (1 << kCloseEvent);
             sd->MarkClosedRead();
           } else if (errno != EWOULDBLOCK) {
             Log::PrintErr("Error recv: %s\n", strerror(errno));
           }
         }
       }
     }
 
-    // On pipes EPOLLHUP is reported without EPOLLIN when there is no
-    // more data to read.
-    if (sd->IsPipe()) {
-      if (((events & EPOLLIN) == 0) &&
-          ((events & EPOLLHUP) != 0)) {
-        event_mask = (1 << kCloseEvent);
-        sd->MarkClosedRead();
-      }
-    } else {
-      // Assert we never get an EPOLLHUP on a non-pipe file-descriptor.
-      ASSERT(events != EPOLLHUP);
-    }
-
     if ((events & EPOLLOUT) != 0) {
       if ((events & EPOLLERR) != 0) {
         event_mask = (1 << kErrorEvent);
         sd->MarkClosedWrite();
       } else {
         event_mask |= (1 << kOutEvent);
       }
     }
-
-    if (events == (EPOLLHUP | EPOLLERR)) {
-      event_mask = (1 << kErrorEvent);
-      sd->MarkClosedWrite();
-      sd->MarkClosedRead();
-    }
   }
 
   return event_mask;
 }
 
 
 void EventHandlerImplementation::HandleEvents(struct epoll_event* events,
                                               int size) {
   for (int i = 0; i < size; i++) {
     if (events[i].data.ptr != NULL) {
@@ skipping 88 matching lines @@
   return reinterpret_cast<void*>(fd + 1);
 }
 
 
 uint32_t EventHandlerImplementation::GetHashmapHashFromFd(intptr_t fd) {
   // The hashmap does not support keys with value 0.
   return dart::Utils::WordHash(fd + 1);
 }
 
 #endif  // defined(TARGET_OS_LINUX)