qatomic.h

qt-x11-opensource-src-4.1.4.tar.gz源码

/****************************************************************************
**
** Copyright (C) 1992-2006 Trolltech ASA. All rights reserved.
**
** This file is part of the QtCore module of the Qt Toolkit.
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** License version 2.0 as published by the Free Software Foundation
** and appearing in the file LICENSE.GPL included in the packaging of
** this file.  Please review the following information to ensure GNU
** General Public Licensing requirements will be met:
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#ifndef MIPS_QATOMIC_H
#define MIPS_QATOMIC_H

#include <QtCore/qglobal.h>

QT_BEGIN_HEADER

extern "C" {
    Q_CORE_EXPORT int q_atomic_test_and_set_int(volatile int *ptr, int expected, int newval);
    Q_CORE_EXPORT int q_atomic_test_and_set_acquire_int(volatile int *ptr, int expected, int newval);    
    Q_CORE_EXPORT int q_atomic_test_and_set_release_int(volatile int *ptr, int expected, int newval);
    Q_CORE_EXPORT int q_atomic_test_and_set_ptr(volatile void *ptr, void *expected, void *newval);
} // extern "C"

inline int q_atomic_increment(volatile int * const ptr)
{
    register int expected;
    for (;;) {
        expected = *ptr;
        if (q_atomic_test_and_set_int(ptr, expected, expected + 1)) break;
    }
    return expected != -1;
}

inline int q_atomic_decrement(volatile int * const ptr)
{
    register int expected;
    for (;;) {
        expected = *ptr;
        if (q_atomic_test_and_set_int(ptr, expected, expected - 1)) break;
    }
    return expected != 1;
}

inline int q_atomic_set_int(volatile int *ptr, int newval)
{
    register int expected;
    for (;;) {
        expected = *ptr;
        if (q_atomic_test_and_set_int(ptr, expected, newval)) break;
    }
    return expected;
}

inline void *q_atomic_set_ptr(volatile void *ptr, void *newval)
{
    register void *expected;
    for (;;) {
        expected = *reinterpret_cast<void * volatile *>(ptr);
        if (q_atomic_test_and_set_ptr(ptr, expected, newval)) break;
    }
    return expected;
}

QT_END_HEADER

#endif // MIPS_QATOMIC_H