condition.c

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/*
 * Copyright (C) 2008 by EmbeddedIT,
 * Ole Reinhardt <ole.reinhardt@embedded-it.de> All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the copyright holders nor the names of
 *    contributors may be used to endorse or promote products derived
 *    from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY EMBEDDED IT AND CONTRIBUTORS
 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL EMBEDDED IT
 * OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * For additional information see http://www.ethernut.de/
 *
 */

/*
 * $Log$
 * Revision 1.3  2008/08/11 07:00:33  haraldkipp
 * BSD types replaced by stdint types (feature request #1282721).
 *
 * Revision 1.2  2008/04/29 01:51:35  thiagocorrea
 * Compile fix
 *
 * Revision 1.1  2008/04/21 22:24:53  olereinhardt
 * Implemented condition variables to use with NutOS as an application candy
 *
 */

#include <sys/heap.h>
#include <sys/event.h>
#include <sys/atom.h>
#include <sys/timer.h>
#include <sys/thread.h>
#include <sys/condition.h>
#include <stddef.h> /* NULL definition */


int NutConditionInit( CONDITION * cond)
{
    cond = NutHeapAlloc(sizeof(struct _CONDITION));
    if (cond == NULL) return 1;
    NutMutexInit(&cond->mutex);
    return 0;
}

void NutConditionLock(CONDITION * cond)
{
    if (cond == NULL) return;
    NutMutexLock(&cond->mutex);
}

void NutConditionUnlock(CONDITION * cond)
{
    if (cond == NULL) return;
    NutMutexUnlock(&cond->mutex);
}

int NutConditionWait(CONDITION * cond)
{
    if (cond == NULL) return -1;
    NutMutexUnlock(&cond->mutex);
    NutEventWait(cond->event, NUT_WAIT_INFINITE);
    NutMutexLock(&cond->mutex);
    return 0;
}

int NutConditionTimedWait(CONDITION * cond, uint32_t abs_ms)
{
    uint32_t ms;

    if (cond == NULL) return -1;
    ms = abs_ms - NutGetMillis();
    if (ms > 0x7FFFFFFF) return -1;

    NutMutexUnlock(&cond->mutex);
    NutEventWait(&cond->event, ms);
    NutMutexLock(&cond->mutex);
    return 0;
}

int NutConditionSignal(CONDITION * cond)
{
    if (cond == NULL) return -1;
    return NutEventPost(&cond->event);
}

int NutConditionBroadcast(CONDITION * cond)
{
    if (cond == NULL) return -1;
    return NutEventBroadcast(&cond->event);
}

void NutConditionFree(CONDITION * cond)
{
    NutMutexDestroy(&cond->mutex);
    NutHeapFree(cond);
    cond = NULL;
}