mirror of https://gitee.com/bigwinds/arangodb
126 lines
4.0 KiB
C++
126 lines
4.0 KiB
C++
////////////////////////////////////////////////////////////////////////////////
|
|
/// DISCLAIMER
|
|
///
|
|
/// Copyright 2014-2016 ArangoDB GmbH, Cologne, Germany
|
|
/// Copyright 2004-2014 triAGENS GmbH, Cologne, Germany
|
|
///
|
|
/// Licensed under the Apache License, Version 2.0 (the "License");
|
|
/// you may not use this file except in compliance with the License.
|
|
/// You may obtain a copy of the License at
|
|
///
|
|
/// http://www.apache.org/licenses/LICENSE-2.0
|
|
///
|
|
/// Unless required by applicable law or agreed to in writing, software
|
|
/// distributed under the License is distributed on an "AS IS" BASIS,
|
|
/// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
/// See the License for the specific language governing permissions and
|
|
/// limitations under the License.
|
|
///
|
|
/// Copyright holder is ArangoDB GmbH, Cologne, Germany
|
|
///
|
|
/// @author Frank Celler
|
|
/// @author Achim Brandt
|
|
////////////////////////////////////////////////////////////////////////////////
|
|
|
|
#ifndef ARANGODB_BASICS_READ_UNLOCKER_H
|
|
#define ARANGODB_BASICS_READ_UNLOCKER_H 1
|
|
|
|
#include "Basics/Common.h"
|
|
#include "Basics/ReadWriteLock.h"
|
|
|
|
////////////////////////////////////////////////////////////////////////////////
|
|
/// @brief construct unlocker with file and line information
|
|
///
|
|
/// Ones needs to use macros twice to get a unique variable based on the line
|
|
/// number.
|
|
////////////////////////////////////////////////////////////////////////////////
|
|
|
|
#ifdef TRI_SHOW_LOCK_TIME
|
|
|
|
#define READ_UNLOCKER(obj, lock) \
|
|
arangodb::basics::ReadUnlocker obj(&lock, __FILE__, __LINE__)
|
|
|
|
#else
|
|
|
|
#define READ_UNLOCKER(obj, lock) arangodb::basics::ReadUnlocker obj(&lock)
|
|
|
|
#endif
|
|
|
|
namespace arangodb {
|
|
namespace basics {
|
|
|
|
////////////////////////////////////////////////////////////////////////////////
|
|
/// @brief read unlocker
|
|
///
|
|
/// A ReadUnlocker unlocks a read-write lock during its lifetime and reacquires
|
|
/// the read-lock again when it is destroyed.
|
|
////////////////////////////////////////////////////////////////////////////////
|
|
|
|
class ReadUnlocker {
|
|
ReadUnlocker(ReadUnlocker const&) = delete;
|
|
ReadUnlocker& operator=(ReadUnlocker const&) = delete;
|
|
|
|
public:
|
|
//////////////////////////////////////////////////////////////////////////////
|
|
/// @brief unlocks the lock
|
|
///
|
|
/// The constructor unlocks the lock, the destructors acquires a read-lock.
|
|
//////////////////////////////////////////////////////////////////////////////
|
|
|
|
#ifdef TRI_SHOW_LOCK_TIME
|
|
|
|
ReadUnlocker(ReadWriteLock* readWriteLock, char const* file, int line)
|
|
: _readWriteLock(readWriteLock), _file(file), _line(line) {
|
|
_readWriteLock->unlockRead();
|
|
}
|
|
|
|
#else
|
|
|
|
explicit ReadUnlocker(ReadWriteLock* readWriteLock)
|
|
: _readWriteLock(readWriteLock) {
|
|
_readWriteLock->unlockRead();
|
|
}
|
|
|
|
#endif
|
|
|
|
////////////////////////////////////////////////////////////////////////////////
|
|
/// @brief unlocks the lock
|
|
///
|
|
/// The constructor unlocks the lock, the destructors acquires a
|
|
/// read-lock.
|
|
////////////////////////////////////////////////////////////////////////////////
|
|
|
|
////////////////////////////////////////////////////////////////////////////////
|
|
/// @brief acquires the read-lock
|
|
////////////////////////////////////////////////////////////////////////////////
|
|
|
|
~ReadUnlocker() { _readWriteLock->readLock(); }
|
|
|
|
private:
|
|
////////////////////////////////////////////////////////////////////////////////
|
|
/// @brief the read-write lock
|
|
////////////////////////////////////////////////////////////////////////////////
|
|
|
|
ReadWriteLock* _readWriteLock;
|
|
|
|
#ifdef TRI_SHOW_LOCK_TIME
|
|
|
|
////////////////////////////////////////////////////////////////////////////////
|
|
/// @brief file
|
|
////////////////////////////////////////////////////////////////////////////////
|
|
|
|
char const* _file;
|
|
|
|
////////////////////////////////////////////////////////////////////////////////
|
|
/// @brief line number
|
|
////////////////////////////////////////////////////////////////////////////////
|
|
|
|
int _line;
|
|
|
|
#endif
|
|
};
|
|
} // namespace basics
|
|
} // namespace arangodb
|
|
|
|
#endif
|