esp-idf/components/bt/common/osi/semaphore.c

78 wiersze
2.1 KiB
C

/******************************************************************************
*
* Copyright (C) 2015 Google, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at:
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
******************************************************************************/
#include "osi/semaphore.h"
/*-----------------------------------------------------------------------------------*/
// Creates and returns a new semaphore. The "init_count" argument specifies
// the initial state of the semaphore, "max_count" specifies the maximum value
// that can be reached.
int osi_sem_new(osi_sem_t *sem, uint32_t max_count, uint32_t init_count)
{
int ret = -1;
if (sem) {
*sem = xSemaphoreCreateCounting(max_count, init_count);
if ((*sem) != NULL) {
ret = 0;
}
}
return ret;
}
/*-----------------------------------------------------------------------------------*/
// Give a semaphore
void osi_sem_give(osi_sem_t *sem)
{
xSemaphoreGive(*sem);
}
/*
Blocks the thread while waiting for the semaphore to be
signaled. If the "timeout" argument is non-zero, the thread should
only be blocked for the specified time (measured in
milliseconds).
*/
int
osi_sem_take(osi_sem_t *sem, uint32_t timeout)
{
int ret = 0;
if (timeout == OSI_SEM_MAX_TIMEOUT) {
if (xSemaphoreTake(*sem, portMAX_DELAY) != pdTRUE) {
ret = -1;
}
} else {
if (xSemaphoreTake(*sem, timeout / portTICK_PERIOD_MS) != pdTRUE) {
ret = -2;
}
}
return ret;
}
// Deallocates a semaphore
void osi_sem_free(osi_sem_t *sem)
{
vSemaphoreDelete(*sem);
*sem = NULL;
}