1/*
2 *  Copyright (c) 2011 The WebRTC project authors. All Rights Reserved.
3 *
4 *  Use of this source code is governed by a BSD-style license
5 *  that can be found in the LICENSE file in the root of the source
6 *  tree. An additional intellectual property rights grant can be found
7 *  in the file PATENTS.  All contributing project authors may
8 *  be found in the AUTHORS file in the root of the source tree.
9 */
10
11#ifndef WEBRTC_SYSTEM_WRAPPERS_INTERFACE_CRITICAL_SECTION_WRAPPER_H_
12#define WEBRTC_SYSTEM_WRAPPERS_INTERFACE_CRITICAL_SECTION_WRAPPER_H_
13
14// If the critical section is heavily contended it may be beneficial to use
15// read/write locks instead.
16
17#include "webrtc/base/thread_annotations.h"
18#include "webrtc/common_types.h"
19
20namespace webrtc {
21class LOCKABLE CriticalSectionWrapper {
22 public:
23  // Factory method, constructor disabled
24  static CriticalSectionWrapper* CreateCriticalSection();
25
26  virtual ~CriticalSectionWrapper() {}
27
28  // Tries to grab lock, beginning of a critical section. Will wait for the
29  // lock to become available if the grab failed.
30  virtual void Enter() EXCLUSIVE_LOCK_FUNCTION() = 0;
31
32  // Returns a grabbed lock, end of critical section.
33  virtual void Leave() UNLOCK_FUNCTION() = 0;
34};
35
36// RAII extension of the critical section. Prevents Enter/Leave mismatches and
37// provides more compact critical section syntax.
38class SCOPED_LOCKABLE CriticalSectionScoped {
39 public:
40  explicit CriticalSectionScoped(CriticalSectionWrapper* critsec)
41      EXCLUSIVE_LOCK_FUNCTION(critsec)
42      : ptr_crit_sec_(critsec) {
43    ptr_crit_sec_->Enter();
44  }
45
46  ~CriticalSectionScoped() UNLOCK_FUNCTION() { ptr_crit_sec_->Leave(); }
47
48 private:
49  CriticalSectionWrapper* ptr_crit_sec_;
50};
51
52}  // namespace webrtc
53
54#endif  // WEBRTC_SYSTEM_WRAPPERS_INTERFACE_CRITICAL_SECTION_WRAPPER_H_
55