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/*
* Copyright (C) 2015 - 2018, IBEROXARXA SERVICIOS INTEGRALES, S.L.
* Copyright (C) 2015 - 2018, Jaume Olivé Petrus (jolive@whitecatboard.org)
*
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * 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.
* * Neither the name of the <organization> nor the
* names of its contributors may be used to endorse or promote products
* derived from this software without specific prior written permission.
* * The WHITECAT logotype cannot be changed, you can remove it, but you
* cannot change it in any way. The WHITECAT logotype is:
*
* /\ /\
* / \_____/ \
* /_____________\
* W H I T E C A T
*
* * Redistributions in binary form must retain all copyright notices printed
* to any local or remote output device. This include any reference to
* Lua RTOS, whitecatboard.org, Lua, and other copyright notices that may
* appear in the future.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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 <COPYRIGHT HOLDER> 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.
*
* Lua RTOS pthread implementation for FreeRTOS
*
*/
#include "_pthread.h"
#include <sys/mutex.h>
#include <sys/time.h>
#if configUSE_16_BIT_TICKS
#define BITS_PER_EVENT_GROUP 8
#else
#define BITS_PER_EVENT_GROUP 24
#endif
int pthread_cond_init(pthread_cond_t *cond, const pthread_condattr_t *attr) {
// Avoid to reinitialize the object referenced by cond, a previously
// initialized, but not yet destroyed, condition variable
if (*cond != PTHREAD_COND_INITIALIZER) {
return EBUSY;
}
// Initialize the internal cond structure
struct pthread_cond *scond = calloc(1, sizeof(struct pthread_cond));
if (!scond) {
return ENOMEM;
}
// Init the cond mutex
mtx_init(&scond->mutex, NULL, NULL, 0);
if (!scond->mutex.lock) {
free(scond);
return ENOMEM;
}
// Create the event group
scond->ev = xEventGroupCreate();
if (scond->ev == NULL) {
mtx_destroy(&scond->mutex);
free(scond);
return ENOMEM;
}
// Return the cond reference
*cond = (pthread_cond_t)scond;
return 0;
}
int pthread_cond_destroy(pthread_cond_t *cond) {
if (*cond == PTHREAD_COND_INITIALIZER) {
return EINVAL;
}
struct pthread_cond *scond = (struct pthread_cond *) *cond;
mtx_lock(&scond->mutex);
if (scond->referenced > 0) {
mtx_unlock(&scond->mutex);
return EBUSY;
}
mtx_destroy(&scond->mutex);
return 0;
}
int pthread_cond_wait(pthread_cond_t *cond, pthread_mutex_t *mutex) {
return pthread_cond_timedwait(cond, mutex, NULL);
}
int pthread_cond_timedwait(pthread_cond_t *cond, pthread_mutex_t *mutex,
const struct timespec *abstime) {
if (*cond == PTHREAD_COND_INITIALIZER) {
return EINVAL;
}
struct pthread_cond *scond = (struct pthread_cond *)*cond;
// Find an unused bit in the event group to sync the condition
mtx_lock(&scond->mutex);
uint8_t bit;
for(bit=0;bit < BITS_PER_EVENT_GROUP;bit++) {
if (!((1 << bit) & scond->referenced)) {
scond->referenced |= (1 << bit);
break;
}
}
mtx_unlock(&scond->mutex);
if (bit >= BITS_PER_EVENT_GROUP) {
// All bits are used in the event group. This is a rare condition, because
// in Lua RTOS an event group has 24 bits, which means that 24 conditions
// (or 24 threads) can be handled for each condition variable.
//
// Although is not part of the pthread specification we indicate this
// condition returning the EINVAL error code.
return EINVAL;
}
// Get the timeout in ticks
TickType_t ticks;
if (!abstime) {
ticks = portMAX_DELAY;
} else {
struct timeval now, future, diff;
gettimeofday(&now, NULL);
future.tv_sec = abstime->tv_sec;
future.tv_usec = abstime->tv_nsec / 1000;
if (timercmp(&future, &now, <)) {
return ETIMEDOUT;
} else {
timersub(&future, &now, &diff);
ticks = ((diff.tv_sec * 1000) + (diff.tv_usec / 1000)) / portTICK_PERIOD_MS;
}
}
pthread_mutex_unlock(mutex);
EventBits_t uxBits = xEventGroupWaitBits(scond->ev, (1 << bit), pdTRUE, pdTRUE, ticks);
if (!(uxBits & (1 << bit))) {
pthread_mutex_lock(mutex);
scond->referenced &= ~(1 << bit);
pthread_mutex_unlock(mutex);
return ETIMEDOUT;
}
pthread_mutex_lock(mutex);
return 0;
}
int pthread_cond_signal(pthread_cond_t *cond) {
if (*cond == PTHREAD_COND_INITIALIZER) {
return EINVAL;
}
struct pthread_cond *scond = (struct pthread_cond *)*cond;
mtx_lock(&scond->mutex);
uint8_t bit;
for(bit=0;bit < BITS_PER_EVENT_GROUP;bit++) {
if ((1 << bit) & scond->referenced) {
xEventGroupSetBits(scond->ev, (1 << bit));
scond->referenced &= ~(1 << bit);
}
}
mtx_unlock(&scond->mutex);
return 0;
}
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