chrome/common/multi_process_lock.h

   1 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef CHROME_COMMON_MULTI_PROCESS_LOCK_H_
   6 #define CHROME_COMMON_MULTI_PROCESS_LOCK_H_
   7
   8 #include <sys/types.h>
   9 #include <string>
  10
  11 // Platform abstraction for a lock that can be shared between processes.
  12 // The process that owns the lock will release it on exit even if
  13 // the exit is due to a crash. Locks are not recursive.
  14 class MultiProcessLock {
  15  public:
  16
  17   // Factory method for creating a multi-process lock.
  18   // |name| is the name of the lock. The name has special meaning on Windows
  19   // where the prefix can determine the namespace of the lock.
  20   // See http://msdn.microsoft.com/en-us/library/aa382954(v=VS.85).aspx for
  21   // details.
  22   static MultiProcessLock* Create(const std::string& name);
  23
  24   virtual ~MultiProcessLock() { }
  25
  26   // Try to grab ownership of the lock.
  27   virtual bool TryLock() = 0;
  28
  29   // Release ownership of the lock.
  30   virtual void Unlock() = 0;
  31 };
  32
  33 #endif  // CHROME_COMMON_MULTI_PROCESS_LOCK_H_