incubator-nuttx/libs/libc/pthread/pthread_condinit.c

86 lines
2.5 KiB
C

/****************************************************************************
* libs/libc/pthread/pthread_condinit.c
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership. The
* ASF licenses this file to you 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.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <pthread.h>
#include <semaphore.h>
#include <debug.h>
#include <errno.h>
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: pthread_cond_init
*
* Description:
* A thread can create condition variables.
*
* Input Parameters:
* None
*
* Returned Value:
* None
*
* Assumptions:
*
****************************************************************************/
int pthread_cond_init(FAR pthread_cond_t *cond,
FAR const pthread_condattr_t *attr)
{
int ret = OK;
sinfo("cond=0x%p attr=0x%p\n", cond, attr);
if (cond == NULL)
{
ret = EINVAL;
}
/* Initialize the semaphore contained in the condition structure with
* initial count = 0
*/
else if (sem_init(&cond->sem, 0, 0) != OK)
{
ret = get_errno();
}
else
{
/* The contained semaphore is used for signaling and, hence, should
* not have priority inheritance enabled.
*/
sem_setprotocol(&cond->sem, SEM_PRIO_NONE);
cond->clockid = attr ? attr->clockid : CLOCK_REALTIME;
}
sinfo("Returning %d\n", ret);
return ret;
}