blob: a9a52d4b7983424d09104a72f84ffad11c8cf88e (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
|
// Copyright (c) 2011 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.
#ifndef BASE_LOCK_IMPL_H_
#define BASE_LOCK_IMPL_H_
#include "base/basictypes.h"
#include "build/build_config.h"
#if defined(OS_WIN)
#include <windows.h>
#elif defined(OS_POSIX)
#include <pthread.h>
#endif
namespace base {
namespace internal {
// This class implements the underlying platform-specific spin-lock mechanism
// used for the Lock class. Most users should not use LockImpl directly, but
// should instead use Lock.
class LockImpl {
public:
#if defined(OS_WIN)
using NativeHandle = SRWLOCK;
#elif defined(OS_POSIX)
using NativeHandle = pthread_mutex_t;
#endif
LockImpl();
~LockImpl();
// If the lock is not held, take it and return true. If the lock is already
// held by something else, immediately return false.
bool Try();
// Take the lock, blocking until it is available if necessary.
void Lock();
// Release the lock. This must only be called by the lock's holder: after
// a successful call to Try, or a call to Lock.
void Unlock();
// Return the native underlying lock.
// TODO(awalker): refactor lock and condition variables so that this is
// unnecessary.
NativeHandle* native_handle() { return &native_handle_; }
#if defined(OS_POSIX)
// Whether this lock will attempt to use priority inheritance.
static bool PriorityInheritanceAvailable();
#endif
private:
NativeHandle native_handle_;
DISALLOW_COPY_AND_ASSIGN(LockImpl);
};
} // namespace internal
} // namespace base
#endif // BASE_LOCK_IMPL_H_
|
