Reland "Introduce optional 'bool shared' parameter to ServerSocket.bind() ..."

dart/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 "bin/eventhandler_linux.h"
 
@@ skipping 223 matching lines @@
         Dart_Port port = msg[i].dart_port;
         di->RemovePort(port);
         intptr_t new_mask = di->Mask();
         UpdateEpollInstance(old_mask, di);
 
         intptr_t fd = di->fd();
         if (di->IsListeningSocket()) {
           // We only close the socket file descriptor from the operating
           // system if there are no other dart socket objects which
           // are listening on the same (address, port) combination.
+          ListeningSocketRegistry *registry =
+              ListeningSocketRegistry::Instance();
 
-          // TODO(dart:io): This assumes that all sockets listen before we
-          // close.
-          // This needs to be synchronized with a global datastructure.
-          if (new_mask == 0) {
-            socket_map_.Remove(
-                GetHashmapKeyFromFd(fd), GetHashmapHashFromFd(fd));
+          MutexLocker locker(registry->mutex());
+
+          if (registry->CloseSafe(fd)) {
+            ASSERT(new_mask == 0);
+            socket_map_.Remove(GetHashmapKeyFromFd(fd),
+                               GetHashmapHashFromFd(fd));
             di->Close();
             delete di;
           }
         } else {
           ASSERT(new_mask == 0);
           socket_map_.Remove(
               GetHashmapKeyFromFd(fd), GetHashmapHashFromFd(fd));
           di->Close();
           delete di;
         }
@@ skipping 150 matching lines @@
 
 uint32_t EventHandlerImplementation::GetHashmapHashFromFd(intptr_t fd) {
   // The hashmap does not support keys with value 0.
   return dart::Utils::WordHash(fd + 1);
 }
 
 }  // namespace bin
 }  // namespace dart
 
 #endif  // defined(TARGET_OS_LINUX)