Make event-handlers edge-triggered and move socket-state to Dart.

runtime/bin/eventhandler_linux.h

Index: runtime/bin/eventhandler_linux.h
diff --git a/runtime/bin/eventhandler_linux.h b/runtime/bin/eventhandler_linux.h
index 2e811e8168c08969cc4668656c82559844d76067..b4a9f604247f33f1599e8d518530e2726471d9b9 100644
--- a/runtime/bin/eventhandler_linux.h
+++ b/runtime/bin/eventhandler_linux.h
@@ -14,6 +14,7 @@
 #include <sys/socket.h>
 
 #include "platform/hashmap.h"
+#include "platform/thread.h"
 
 
 namespace dart {
@@ -27,46 +28,30 @@ class InterruptMessage {
 };
 
 
-enum PortDataFlags {
-  kClosedRead = 0,
-  kClosedWrite = 1,
-};
-
-
 class SocketData {
  public:
   explicit SocketData(intptr_t fd)
-      : tracked_by_epoll_(false), fd_(fd), port_(0), mask_(0), flags_(0) {
+      : tracked_by_epoll_(false), fd_(fd), port_(0), mask_(0) {
     ASSERT(fd_ != -1);
   }
 
-  intptr_t GetPollEvents();
-
   void ShutdownRead() {
     shutdown(fd_, SHUT_RD);
-    MarkClosedRead();
   }
 
   void ShutdownWrite() {
     shutdown(fd_, SHUT_WR);
-    MarkClosedWrite();
   }
 
   void Close() {
     port_ = 0;
     mask_ = 0;
-    flags_ = 0;
     close(fd_);
     fd_ = -1;
   }
 
   bool IsListeningSocket() { return (mask_ & (1 << kListeningSocket)) != 0; }
   bool IsPipe() { return (mask_ & (1 << kPipe)) != 0; }
-  bool IsClosedRead() { return (flags_ & (1 << kClosedRead)) != 0; }
-  bool IsClosedWrite() { return (flags_ & (1 << kClosedWrite)) != 0; }
-
-  void MarkClosedRead() { flags_ |= (1 << kClosedRead); }
-  void MarkClosedWrite() { flags_ |= (1 << kClosedWrite); }
 
   void SetPortAndMask(Dart_Port port, intptr_t mask) {
     ASSERT(fd_ != -1);
@@ -85,7 +70,6 @@ class SocketData {
   intptr_t fd_;
   Dart_Port port_;
   intptr_t mask_;
-  intptr_t flags_;
 };
 
 
@@ -96,7 +80,7 @@ class EventHandlerImplementation {
 
   // Gets the socket data structure for a given file
   // descriptor. Creates a new one if one is not found.
-  SocketData* GetSocketData(intptr_t fd);
+  SocketData* GetSocketData(intptr_t fd, bool* is_new);
   void SendData(intptr_t id, Dart_Port dart_port, int64_t data);
   void Start(EventHandler* handler);
   void Shutdown();