1 files changed, 51 insertions, 0 deletions
diff --git a/chrome/common/net/thread_blocker.cc b/chrome/common/net/thread_blocker.cc
new file mode 100644
index 0000000..4ecce8a
--- /dev/null
+++ b/chrome/common/net/thread_blocker.cc
@@ -0,0 +1,51 @@
+// Copyright (c) 2010 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "chrome/common/net/thread_blocker.h"
+
+#include "base/logging.h"
+#include "base/message_loop.h"
+#include "base/task.h"
+#include "base/thread.h"
+#include "base/waitable_event.h"
+
+// Since a ThreadBlocker is outlived by its target thread, we don't
+// have to ref-count it.
+template <>
+struct RunnableMethodTraits<chrome_common_net::ThreadBlocker> {
+  void RetainCallee(chrome_common_net::ThreadBlocker*) {}
+  void ReleaseCallee(chrome_common_net::ThreadBlocker*) {}
+};
+
+namespace chrome_common_net {
+
+ThreadBlocker::ThreadBlocker(base::Thread* target_thread)
+    : target_message_loop_(target_thread->message_loop()),
+      is_blocked_(false, false), is_finished_blocking_(false, false),
+      is_unblocked_(false, false) {
+  DCHECK(target_message_loop_);
+}
+
+void ThreadBlocker::Block() {
+  DCHECK_NE(MessageLoop::current(), target_message_loop_);
+  target_message_loop_->PostTask(
+      FROM_HERE,
+      NewRunnableMethod(this, &ThreadBlocker::BlockOnTargetThread));
+  while (!is_blocked_.Wait()) {}
+}
+
+void ThreadBlocker::Unblock() {
+  DCHECK_NE(MessageLoop::current(), target_message_loop_);
+  is_finished_blocking_.Signal();
+  while (!is_unblocked_.Wait()) {}
+}
+
+void ThreadBlocker::BlockOnTargetThread() {
+  DCHECK_EQ(MessageLoop::current(), target_message_loop_);
+  is_blocked_.Signal();
+  while (!is_finished_blocking_.Wait()) {}
+  is_unblocked_.Signal();
+}
+
+}  // namespace chrome_common_net