Explicitly handle listen sockets and connection sockets differently in Linux and Mac OS eventhandler

runtime/bin/eventhandler_linux.cc

Index: runtime/bin/eventhandler_linux.cc
diff --git a/runtime/bin/eventhandler_linux.cc b/runtime/bin/eventhandler_linux.cc
index a72f42a36ed6794f39ba5208ff642246e2e72e5a..c80c620d0af83624b2c02473f6502893a6cf70a8 100644
--- a/runtime/bin/eventhandler_linux.cc
+++ b/runtime/bin/eventhandler_linux.cc
@@ -96,6 +96,11 @@ Dart_Port EventHandlerImplementation::PortFor(intptr_t fd) {
 }
 
 
+bool EventHandlerImplementation::IsListeningSocket(intptr_t fd) {
+  return (port_map_[fd].mask & (1 << kListenSocket)) != 0;

[Mads Ager (google), 2011/10/28 08:33:23]

kListeningSocket?

[Søren Gjesse, 2011/10/28 09:24:19]

Done.

+}
+
+
 void EventHandlerImplementation::RegisterFdWakeup(intptr_t id,
                                                   Dart_Port dart_port,
                                                   intptr_t data) {
@@ -136,17 +141,15 @@ void EventHandlerImplementation::WakeupHandler(intptr_t id,
 
 void EventHandlerImplementation::SetPollEvents(struct pollfd* pollfds,
                                                intptr_t mask) {
-  /*
-   * We do not set POLLERR and POLLHUP explicitly since they are triggered
-   * anyway.
-   */
-  pollfds->events |= POLLRDHUP;
+  // Do not ask for POLLERR and POLLHUP explicitly as they are
+  // triggered anyway.
   if ((mask & (1 << kInEvent)) != 0) {
     pollfds->events |= POLLIN;
   }
   if ((mask & (1 << kOutEvent)) != 0) {
     pollfds->events |= POLLOUT;
   }
+  pollfds->events |= POLLRDHUP;
 }
 
 
@@ -213,27 +216,26 @@ void EventHandlerImplementation::HandleInterruptFd() {
 
 intptr_t EventHandlerImplementation::GetPollEvents(struct pollfd* pollfd) {
   intptr_t event_mask = 0;
-  /*
-   * We prioritize the events in the following order.
-   */
-  if ((pollfd->revents & POLLIN) != 0) {
-    if (FDUtils::AvailableBytes(pollfd->fd) != 0) {
-      event_mask = (1 << kInEvent);
-    } else if (((pollfd->revents & POLLHUP) != 0) ||
-               ((pollfd->revents & POLLRDHUP) != 0)) {
-      event_mask = (1 << kCloseEvent);
-    } else if ((pollfd->revents & POLLERR) != 0) {
-      event_mask = (1 << kErrorEvent);
-    } else {
-      /*
-       * Accept event.
-       */
-      event_mask = (1 << kInEvent);
+  if (IsListeningSocket(pollfd->fd)) {
+    // For listening sockets the POLLIN event indicate that there are
+    // connections ready for accept.
+    if ((pollfd->revents & POLLIN) != 0) event_mask |= (1 << kInEvent);

[Mads Ager (google), 2011/10/28 08:33:23]

Should we assert that there is no overlap in these? Can we ever get more than
one of these and what does that mean?

[Søren Gjesse, 2011/10/28 09:24:19]

I would be reluctant to try to assert anything here. However reading the
documentation once more both POLLHUP and POLLERR are always provided together
with POLLIN, so POLLIN should only mean "connections ready for accept" if
provided alone.

+    if ((pollfd->revents & POLLHUP) != 0) event_mask |= (1 << kCloseEvent);
+    if ((pollfd->revents & POLLERR) != 0) event_mask |= (1 << kErrorEvent);
+  } else {
+    // Prioritize data events over close and error events.
+    if ((pollfd->revents & POLLIN) != 0) {
+      if (FDUtils::AvailableBytes(pollfd->fd) != 0) {
+        event_mask = (1 << kInEvent);
+      } else if (((pollfd->revents & POLLHUP) != 0) ||
+                 ((pollfd->revents & POLLRDHUP) != 0)) {
+        event_mask = (1 << kCloseEvent);
+      } else if ((pollfd->revents & POLLERR) != 0) {
+        event_mask = (1 << kErrorEvent);
+      }
     }
-  }
 
-  if ((pollfd->revents & POLLOUT) != 0) {
-    event_mask |= (1 << kOutEvent);
+    if ((pollfd->revents & POLLOUT) != 0) event_mask |= (1 << kOutEvent);
   }
 
   return event_mask;