mirror of
https://github.com/klzgrad/naiveproxy.git
synced 2024-12-01 01:36:09 +03:00
79 lines
2.0 KiB
C
79 lines
2.0 KiB
C
|
// 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_SYNCHRONIZATION_LOCK_IMPL_H_
|
||
|
|
#define BASE_SYNCHRONIZATION_LOCK_IMPL_H_
|
||
|
|
|
||
|
|
#include "base/base_export.h"
|
||
|
|
#include "base/logging.h"
|
||
|
|
#include "base/macros.h"
|
||
|
|
#include "build/build_config.h"
|
||
|
|
|
||
|
|
#if defined(OS_WIN)
|
||
|
|
#include <windows.h>
|
||
|
|
#elif defined(OS_POSIX)
|
||
|
|
#include <errno.h>
|
||
|
|
#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 BASE_EXPORT 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.
|
||
|
|
inline 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);
|
||
|
|
};
|
||
|
|
|
||
|
|
#if defined(OS_WIN)
|
||
|
|
void LockImpl::Unlock() {
|
||
|
|
::ReleaseSRWLockExclusive(&native_handle_);
|
||
|
|
}
|
||
|
|
#elif defined(OS_POSIX)
|
||
|
|
void LockImpl::Unlock() {
|
||
|
|
int rv = pthread_mutex_unlock(&native_handle_);
|
||
|
|
DCHECK_EQ(rv, 0) << ". " << strerror(rv);
|
||
|
|
}
|
||
|
|
#endif
|
||
|
|
|
||
|
|
} // namespace internal
|
||
|
|
} // namespace base
|
||
|
|
|
||
|
|
#endif // BASE_SYNCHRONIZATION_LOCK_IMPL_H_
|