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pip/libs/main/thread/pireadwritelock.h

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4.9 KiB
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/*! \file pireadwritelock.h
* \ingroup Read/Write lock
* \~\brief
* \~english Read/Write lock
* \~russian Блокировка чтения/записи
*/
/*
PIP - Platform Independent Primitives
PIReadWriteLock, PIReadLocker, PIWriteLocker
Ivan Pelipenko peri4ko@yandex.ru
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef PIREADWRITELOCK_H
#define PIREADWRITELOCK_H
#include "piconditionvar.h"
class PIP_EXPORT PIReadWriteLock {
public:
NO_COPY_CLASS(PIReadWriteLock)
//! \~english Constructs %PIReadWriteLock.
//! \~russian Создает %PIReadWriteLock.
PIReadWriteLock();
//! \~english Destroy %PIReadWriteLock.
//! \~russian Деструктор %PIReadWriteLock.
~PIReadWriteLock();
//! \~english Lock for write. If already locked for write or read, than wait until all locks released.
//! \~russian Заблокировать на запись. Если уже заблокировано на запись или чтение, то ждёт освобождения блокировок.
void lockWrite();
//! \~english Try to lock for write. Returns if operation was successfull.
//! \~russian Пробует заблокировать на запись. Возвращает успех операции.
bool tryLockWrite();
//! \~english Try to lock for write for \"timeout\". Returns if operation was successfull (timeout has not expired).
//! \~russian Пробует заблокировать на запись в течении \"timeout\". Возвращает успех операции (не истек ли тайм-аут).
bool tryLockWrite(PISystemTime timeout);
//! \~english Release lock for write.
//! \~russian Освобождает блокировку на запись.
void unlockWrite();
//! \~english Lock for read. If already locked for write, than wait until write lock released.
//! \~russian Заблокировать на чтение. Если уже заблокировано на запись, то ждёт освобождения записывающей блокировки.
void lockRead();
//! \~english Try to lock for read. Returns if operation was successfull.
//! \~russian Пробует заблокировать на чтение. Возвращает успех операции.
bool tryLockRead();
//! \~english Try to lock for read for \"timeout\". Returns if operation was successfull (timeout has not expired).
//! \~russian Пробует заблокировать на чтение в течении \"timeout\". Возвращает успех операции (не истек ли тайм-аут).
bool tryLockRead(PISystemTime timeout);
//! \~english Release lock for read.
//! \~russian Освобождает блокировку на чтение.
void unlockRead();
private:
int reading = 0;
bool writing = false;
PIMutex mutex;
PIConditionVariable var;
};
class PIP_EXPORT PIReadLocker {
public:
NO_COPY_CLASS(PIReadLocker);
//! \~english Constructs and lock for read %PIReadWriteLock "l" if "condition" is \c true.
//! \~russian Создается и блокирует на чтение %PIReadWriteLock "l" если "condition" \c true.
PIReadLocker(PIReadWriteLock & l, bool condition = true): rwl(l), cond(condition) {
if (cond) rwl.lockRead();
}
//! \~english Release read lock on %PIReadWriteLock if "condition" was \c true.
//! \~russian Освобождает блокировку на чтение %PIReadWriteLock если "condition" был \c true.
~PIReadLocker() {
if (cond) rwl.unlockRead();
}
private:
PIReadWriteLock & rwl;
bool cond = true;
};
class PIP_EXPORT PIWriteLocker {
public:
NO_COPY_CLASS(PIWriteLocker);
//! \~english Constructs and lock for write %PIReadWriteLock "l" if "condition" is \c true.
//! \~russian Создается и блокирует на запись %PIReadWriteLock "l" если "condition" \c true.
PIWriteLocker(PIReadWriteLock & l, bool condition = true): rwl(l), cond(condition) {
if (cond) rwl.lockWrite();
}
//! \~english Release write lock on %PIReadWriteLock if "condition" was \c true.
//! \~russian Освобождает блокировку на запись %PIReadWriteLock если "condition" был \c true.
~PIWriteLocker() {
if (cond) rwl.unlockWrite();
}
private:
PIReadWriteLock & rwl;
bool cond = true;
};
#endif