Add multi_process_lock to chrome/common

chrome/common/multi_process_lock_win.cc

+// 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/multi_process_lock.h"
+
+#include "base/utf_string_conversions.h"
+#include "base/win/scoped_handle.h"
+
+class MultiProcessLockWin : public MultiProcessLock {
+ public:
+  explicit MultiProcessLockWin(const std::string& name)
+      : MultiProcessLock(name) { }
+
+  virtual ~MultiProcessLockWin() { Unlock(); }
+
+  virtual bool TryLock() {
+    string16 wname = UTF8ToUTF16(name_);
+    event_.Set(CreateEvent(NULL, FALSE, FALSE, wname.c_str()));

[sanjeevr, 2010/11/11 22:06:56]

CreateEvent will succeed even if the event already existed. You need to check
for GetLastError() != ERROR_ALREADY_EXISTS.

[dmac, 2010/11/11 23:33:02]

Done.

+    return event_.Get() != NULL;
+  }
+
+  virtual void Unlock() {
+    event_.Set(NULL);
+  }
+
+ private:
+  base::win::ScopedHandle event_;
+  DISALLOW_COPY_AND_ASSIGN(MultiProcessLockWin);
+};
+
+MultiProcessLock* MultiProcessLock::Create(const std::string &name) {
+  return new MultiProcessLockWin(name);
+}