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Diffstat (limited to 'tqtinterface/qt4/src/tools/tqsemaphore.cpp')
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diff --git a/tqtinterface/qt4/src/tools/tqsemaphore.cpp b/tqtinterface/qt4/src/tools/tqsemaphore.cpp deleted file mode 100644 index 7f1eff9..0000000 --- a/tqtinterface/qt4/src/tools/tqsemaphore.cpp +++ /dev/null @@ -1,255 +0,0 @@ -/**************************************************************************** -** -** TQSemaphore class for Unix -** -** Created : 20010725 -** -** Copyright (C) 2010 Timothy Pearson and (C) 1992-2008 Trolltech ASA. -** -** This file is part of the tools module of the TQt GUI Toolkit. -** -** This file may be used under the terms of the GNU General -** Public License versions 2.0 or 3.0 as published by the Free -** Software Foundation and appearing in the files LICENSE.GPL2 -** and LICENSE.GPL3 included in the packaging of this file. -** Alternatively you may (at your option) use any later version -** of the GNU General Public License if such license has been -** publicly approved by Trolltech ASA (or its successors, if any) -** and the KDE Free TQt Foundation. -** -** Please review the following information to ensure GNU General -** Public Licensing requirements will be met: -** http://trolltech.com/products/qt/licenses/licensing/opensource/. -** If you are unsure which license is appropriate for your use, please -** review the following information: -** http://trolltech.com/products/qt/licenses/licensing/licensingoverview -** or contact the sales department at sales@trolltech.com. -** -** This file may be used under the terms of the Q Public License as -** defined by Trolltech ASA and appearing in the file LICENSE.TQPL -** included in the packaging of this file. Licensees holding valid TQt -** Commercial licenses may use this file in accordance with the TQt -** Commercial License Agreement provided with the Software. -** -** This file is provided "AS IS" with NO WARRANTY OF ANY KIND, -** INCLUDING THE WARRANTIES OF DESIGN, MERCHANTABILITY AND FITNESS FOR -** A PARTICULAR PURPOSE. Trolltech reserves all rights not granted -** herein. -** -**********************************************************************/ - -#if defined(TQT_THREAD_SUPPORT) - -#include "tqsemaphore.h" -#include "tqmutex.h" -#include "tqwaitcondition.h" - - -/*! - \class TQSemaphore tqsemaphore.h - \threadsafe - \brief The TQSemaphore class provides a robust integer semaphore. - - \ingroup thread - \ingroup environment - - A TQSemaphore can be used to serialize thread execution, in a - similar way to a TQMutex. A semaphore differs from a mutex, in - that a semaphore can be accessed by more than one thread at a - time. - - For example, suppose we have an application that stores data in a - large tree structure. The application creates 10 threads - (commonly called a thread pool) to perform searches on the tree. - When the application searches the tree for some piece of data, it - uses one thread per base node to do the searching. A semaphore - could be used to make sure that two threads don't try to search - the same branch of the tree at the same time. - - A non-computing example of a semaphore would be dining at a - restuarant. A semaphore is initialized to have a maximum count - equal to the number of chairs in the restuarant. As people - arrive, they want a seat. As seats are filled, the semaphore is - accessed, once per person. As people leave, the access is - released, allowing more people to enter. If a party of 10 people - want to be seated, but there are only 9 seats, those 10 people - will wait, but a party of 4 people would be seated (taking the - available seats to 5, making the party of 10 people wait longer). - - When a semaphore is created it is given a number which is the - maximum number of concurrent accesses it will permit. Accesses to - the sempahore are gained using operator++() or operator+=(), and - released with operator--() or operator-=(). The number of - accesses allowed is retrieved with available(), and the total - number with total(). Note that the incrementing functions will - block if there aren't enough available accesses. Use tryAccess() - if you want to acquire accesses without blocking. -*/ - - -class TQSemaphorePrivate { -public: - TQSemaphorePrivate(int); - - TQMutex mutex; - TQWaitCondition cond; - - int value, max; -}; - - -TQSemaphorePrivate::TQSemaphorePrivate(int m) - : mutex(FALSE), value(0), max(m) -{ -} - - -/*! - Creates a new semaphore. The semaphore can be concurrently - accessed at most \a maxcount times. -*/ -TQSemaphore::TQSemaphore(int maxcount) -{ - d = new TQSemaphorePrivate(maxcount); -} - - -/*! - Destroys the semaphore. - - \warning If you destroy a semaphore that has accesses in use the - resultant behavior is undefined. -*/ -TQSemaphore::~TQSemaphore() -{ - delete d; -} - - -/*! - Postfix ++ operator. - - Try to get access to the semaphore. If \l available() == 0, this - call will block until it can get access, i.e. until available() \> - 0. -*/ -int TQSemaphore::operator++(int) -{ - TQMutexLocker locker(&d->mutex); - while (d->value >= d->max) - d->cond.wait(locker.mutex()); - - ++d->value; - if (d->value > d->max) - d->value = d->max; - - return d->value; -} - - -/*! - Postfix -- operator. - - Release access of the semaphore. This wakes all threads waiting - for access to the semaphore. -*/ -int TQSemaphore::operator--(int) -{ - TQMutexLocker locker(&d->mutex); - - --d->value; - if (d->value < 0) - d->value = 0; - - d->cond.wakeAll(); - - return d->value; -} - - -/*! - Try to get access to the semaphore. If \l available() \< \a n, this - call will block until it can get all the accesses it wants, i.e. - until available() \>= \a n. -*/ -int TQSemaphore::operator+=(int n) -{ - TQMutexLocker locker(&d->mutex); - - if ( n < 0 || n > d->max ) { -#ifdef TQT_CHECK_RANGE - qWarning( "TQSemaphore::operator+=: paramter %d out of range", n ); -#endif // TQT_CHECK_RANGE - n = n < 0 ? 0 : d->max; - } - - while (d->value + n > d->max) - d->cond.wait(locker.mutex()); - - d->value += n; - - return d->value; -} - - -/*! - Release \a n accesses to the semaphore. -*/ -int TQSemaphore::operator-=(int n) -{ - TQMutexLocker locker(&d->mutex); - - if ( n < 0 || n > d->value ) { -#ifdef TQT_CHECK_RANGE - qWarning( "TQSemaphore::operator-=: paramter %d out of range", n ); -#endif // TQT_CHECK_RANGE - n = n < 0 ? 0 : d->value; - } - - d->value -= n; - d->cond.wakeAll(); - - return d->value; -} - - -/*! - Returns the number of accesses currently available to the - semaphore. -*/ -int TQSemaphore::available() const -{ - TQMutexLocker locker(&d->mutex); - return d->max - d->value; -} - - -/*! - Returns the total number of accesses to the semaphore. -*/ -int TQSemaphore::total() const -{ - TQMutexLocker locker(&d->mutex); - return d->max; -} - - -/*! - Try to get access to the semaphore. If \l available() \< \a n, this - function will return FALSE immediately. If \l available() \>= \a n, - this function will take \a n accesses and return TRUE. This - function does \e not block. -*/ -bool TQSemaphore::tryAccess(int n) -{ - TQMutexLocker locker(&d->mutex); - - if (d->value + n > d->max) - return FALSE; - - d->value += n; - - return TRUE; -} - -#endif // TQT_THREAD_SUPPORT |