Terminate event handler thread on isolate shutdown.

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 e15f3dfd6b39da908c9552a7d124fdb07547d7e3..6b0a70b7a065261d390540a2af96ebabbfbf8f1b 100644
--- a/runtime/bin/eventhandler_linux.cc
+++ b/runtime/bin/eventhandler_linux.cc
@@ -33,6 +33,7 @@ int64_t GetCurrentTimeMilliseconds() {
 static const int kInterruptMessageSize = sizeof(InterruptMessage);
 static const int kInfinityTimeout = -1;
 static const int kTimerId = -1;
+static const int kShutdownId = -2;
 
 
 intptr_t SocketData::GetPollEvents() {
@@ -105,6 +106,7 @@ EventHandlerImplementation::EventHandlerImplementation()
   FDUtils::SetNonBlocking(interrupt_fds_[0]);
   timeout_ = kInfinityTimeout;
   timeout_port_ = 0;
+  shutdown_ = false;
   // The initial size passed to epoll_create is ignore on newer (>=
   // 2.6.8) Linux versions
   static const int kEpollInitialSize = 64;
@@ -193,6 +195,8 @@ void EventHandlerImplementation::HandleInterruptFd() {
     if (msg.id == kTimerId) {
       timeout_ = msg.data;
       timeout_port_ = msg.dart_port;
+    } else if (msg.id == kShutdownId) {
+      shutdown_ = true;
     } else {
       SocketData* sd = GetSocketData(msg.id);
       if ((msg.data & (1 << kShutdownReadCommand)) != 0) {
@@ -373,7 +377,7 @@ void EventHandlerImplementation::Poll(uword args) {
   EventHandlerImplementation* handler =
       reinterpret_cast<EventHandlerImplementation*>(args);
   ASSERT(handler != NULL);
-  while (1) {
+  while (true) {

[Søren Gjesse, 2012/06/29 11:54:11]

Maybe "while (!handler->shutdown_)" here and no new if at the bottom of the
loop?

Same for Mac OS and Windows.

[Mads Ager (google), 2012/06/29 14:30:24]

Absolutely! Thanks for catching that. 

     intptr_t millis = handler->GetTimeout();
     intptr_t result = TEMP_FAILURE_RETRY(epoll_wait(handler->epoll_fd_,
                                                     events,
@@ -388,6 +392,7 @@ void EventHandlerImplementation::Poll(uword args) {
       handler->HandleTimeout();
       handler->HandleEvents(events, result);
     }
+    if (handler->shutdown_) break;
   }
 }
 
@@ -401,6 +406,11 @@ void EventHandlerImplementation::StartEventHandler() {
 }
 
 
+void EventHandlerImplementation::Shutdown() {
+  SendData(kShutdownId, 0, 0);
+}
+
+
 void EventHandlerImplementation::SendData(intptr_t id,
                                           Dart_Port dart_port,
                                           intptr_t data) {