poco/Foundation/include/Poco/Mutex.h

238 lines
6.6 KiB
C
Raw Normal View History

2006-10-23 17:48:43 +02:00
//
// Mutex.h
//
2008-01-28 18:23:19 +01:00
// $Id: //poco/svn/Foundation/include/Poco/Mutex.h#3 $
2006-10-23 17:48:43 +02:00
//
// Library: Foundation
// Package: Threading
// Module: Mutex
//
// Definition of the Mutex and FastMutex classes.
//
2008-01-28 18:23:19 +01:00
// Copyright (c) 2004-2008, Applied Informatics Software Engineering GmbH.
2006-10-23 17:48:43 +02:00
// and Contributors.
//
// Permission is hereby granted, free of charge, to any person or organization
// obtaining a copy of the software and accompanying documentation covered by
// this license (the "Software") to use, reproduce, display, distribute,
// execute, and transmit the Software, and to prepare derivative works of the
// Software, and to permit third-parties to whom the Software is furnished to
// do so, all subject to the following:
//
// The copyright notices in the Software and this entire statement, including
// the above license grant, this restriction and the following disclaimer,
// must be included in all copies of the Software, in whole or in part, and
// all derivative works of the Software, unless such copies or derivative
// works are solely in the form of machine-executable object code generated by
// a source language processor.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE, TITLE AND NON-INFRINGEMENT. IN NO EVENT
// SHALL THE COPYRIGHT HOLDERS OR ANYONE DISTRIBUTING THE SOFTWARE BE LIABLE
// FOR ANY DAMAGES OR OTHER LIABILITY, WHETHER IN CONTRACT, TORT OR OTHERWISE,
// ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
// DEALINGS IN THE SOFTWARE.
//
#ifndef Foundation_Mutex_INCLUDED
#define Foundation_Mutex_INCLUDED
#include "Poco/Foundation.h"
2008-01-28 18:23:19 +01:00
#include "Poco/Exception.h"
2006-10-23 17:48:43 +02:00
#include "Poco/ScopedLock.h"
#if defined(POCO_OS_FAMILY_WINDOWS)
#include "Poco/Mutex_WIN32.h"
#else
#include "Poco/Mutex_POSIX.h"
#endif
namespace Poco {
class Foundation_API Mutex: private MutexImpl
/// A Mutex (mutual exclusion) is a synchronization
/// mechanism used to control access to a shared resource
/// in a concurrent (multithreaded) scenario.
/// Mutexes are recursive, that is, the same mutex can be
/// locked multiple times by the same thread (but, of course,
/// not by other threads).
/// Using the ScopedLock class is the preferred way to automatically
/// lock and unlock a mutex.
{
public:
typedef Poco::ScopedLock<Mutex> ScopedLock;
Mutex();
/// creates the Mutex.
~Mutex();
/// destroys the Mutex.
void lock();
/// Locks the mutex. Blocks if the mutex
/// is held by another thread.
2008-01-28 18:23:19 +01:00
void lock(long milliseconds);
/// Locks the mutex. Blocks up to the given number of milliseconds
/// if the mutex is held by another thread. Throws a TimeoutException
/// if the mutex can not be locked within the given timeout.
///
/// Performance Note: On most platforms (including Windows), this member function is
/// implemented using a loop calling (the equivalent of) tryLock() and Thread::sleep().
/// On POSIX platforms that support pthread_mutex_timedlock(), this is used.
2006-10-23 17:48:43 +02:00
bool tryLock();
/// Tries to lock the mutex. Returns false immediately
/// if the mutex is already held by another thread.
/// Returns true if the mutex was successfully locked.
2008-01-28 18:23:19 +01:00
bool tryLock(long milliseconds);
/// Locks the mutex. Blocks up to the given number of milliseconds
/// if the mutex is held by another thread.
/// Returns true if the mutex was successfully locked.
///
/// Performance Note: On most platforms (including Windows), this member function is
/// implemented using a loop calling (the equivalent of) tryLock() and Thread::sleep().
/// On POSIX platforms that support pthread_mutex_timedlock(), this is used.
2006-10-23 17:48:43 +02:00
void unlock();
/// Unlocks the mutex so that it can be acquired by
/// other threads.
private:
Mutex(const Mutex&);
Mutex& operator = (const Mutex&);
};
class Foundation_API FastMutex: private FastMutexImpl
/// A FastMutex (mutual exclusion) is similar to a Mutex.
/// Unlike a Mutex, however, a FastMutex is not recursive,
/// which means that a deadlock will occur if the same
/// thread tries to lock a mutex it has already locked again.
/// Locking a FastMutex is faster than locking a recursive Mutex.
/// Using the ScopedLock class is the preferred way to automatically
/// lock and unlock a mutex.
{
public:
typedef Poco::ScopedLock<FastMutex> ScopedLock;
FastMutex();
/// creates the Mutex.
~FastMutex();
/// destroys the Mutex.
void lock();
/// Locks the mutex. Blocks if the mutex
/// is held by another thread.
2008-01-28 18:23:19 +01:00
void lock(long milliseconds);
/// Locks the mutex. Blocks up to the given number of milliseconds
/// if the mutex is held by another thread. Throws a TimeoutException
/// if the mutex can not be locked within the given timeout.
///
/// Performance Note: On most platforms (including Windows), this member function is
/// implemented using a loop calling (the equivalent of) tryLock() and Thread::sleep().
/// On POSIX platforms that support pthread_mutex_timedlock(), this is used.
2006-10-23 17:48:43 +02:00
bool tryLock();
/// Tries to lock the mutex. Returns false immediately
/// if the mutex is already held by another thread.
/// Returns true if the mutex was successfully locked.
2008-01-28 18:23:19 +01:00
bool tryLock(long milliseconds);
/// Locks the mutex. Blocks up to the given number of milliseconds
/// if the mutex is held by another thread.
/// Returns true if the mutex was successfully locked.
///
/// Performance Note: On most platforms (including Windows), this member function is
/// implemented using a loop calling (the equivalent of) tryLock() and Thread::sleep().
/// On POSIX platforms that support pthread_mutex_timedlock(), this is used.
2006-10-23 17:48:43 +02:00
void unlock();
/// Unlocks the mutex so that it can be acquired by
/// other threads.
private:
FastMutex(const FastMutex&);
FastMutex& operator = (const FastMutex&);
};
//
// inlines
//
inline void Mutex::lock()
{
lockImpl();
}
2008-01-28 18:23:19 +01:00
inline void Mutex::lock(long milliseconds)
{
if (!tryLockImpl(milliseconds))
throw TimeoutException();
}
2006-10-23 17:48:43 +02:00
inline bool Mutex::tryLock()
{
return tryLockImpl();
}
2008-01-28 18:23:19 +01:00
inline bool Mutex::tryLock(long milliseconds)
{
return tryLockImpl(milliseconds);
}
2006-10-23 17:48:43 +02:00
inline void Mutex::unlock()
{
unlockImpl();
}
inline void FastMutex::lock()
{
lockImpl();
}
2008-01-28 18:23:19 +01:00
inline void FastMutex::lock(long milliseconds)
{
if (!tryLockImpl(milliseconds))
throw TimeoutException();
}
2006-10-23 17:48:43 +02:00
inline bool FastMutex::tryLock()
{
return tryLockImpl();
}
2008-01-28 18:23:19 +01:00
inline bool FastMutex::tryLock(long milliseconds)
{
return tryLockImpl(milliseconds);
}
2006-10-23 17:48:43 +02:00
inline void FastMutex::unlock()
{
unlockImpl();
}
} // namespace Poco
#endif // Foundation_Mutex_INCLUDED