cef/include/base/internal/cef_lock_impl.h

88 lines
3.1 KiB
C++

// Copyright (c) 2011 Google Inc. All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
// * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following disclaimer
// in the documentation and/or other materials provided with the
// distribution.
// * Neither the name of Google Inc. nor the name Chromium Embedded
// Framework nor the names of its contributors may be used to endorse
// or promote products derived from this software without specific prior
// written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
// Do not include this header file directly. Use base/cef_lock.h instead.
#ifndef CEF_INCLUDE_BASE_INTERNAL_CEF_LOCK_IMPL_H_
#define CEF_INCLUDE_BASE_INTERNAL_CEF_LOCK_IMPL_H_
#include "include/base/cef_build.h"
#if defined(OS_WIN)
#include <windows.h>
#elif defined(OS_POSIX)
#include <pthread.h>
#endif
namespace base {
namespace cef_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)
typedef CRITICAL_SECTION NativeHandle;
#elif defined(OS_POSIX)
typedef pthread_mutex_t NativeHandle;
#endif
LockImpl();
LockImpl(const LockImpl&) = delete;
LockImpl& operator=(const LockImpl&) = delete;
~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_; }
private:
NativeHandle native_handle_;
};
} // namespace cef_internal
} // namespace base
#endif // CEF_INCLUDE_BASE_INTERNAL_CEF_LOCK_IMPL_H_