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/********************************************************************************
* sched/pthread_barrieinit.c
*
* Copyright (C) 2007, 2009 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* 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 NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* 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 THE
* COPYRIGHT OWNER 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.
*
********************************************************************************/
/********************************************************************************
* Included Files
********************************************************************************/
#include <nuttx/config.h>
#include <pthread.h>
#include <semaphore.h>
#include <errno.h>
#include <debug.h>
/********************************************************************************
* Definitions
********************************************************************************/
/********************************************************************************
* Private Type Declarations
********************************************************************************/
/********************************************************************************
* Global Variables
********************************************************************************/
/********************************************************************************
* Private Variables
********************************************************************************/
/********************************************************************************
* Private Function Prototypes
********************************************************************************/
/********************************************************************************
* Public Functions
********************************************************************************/
/********************************************************************************
* Name: pthread_barrier_init
*
* Description:
* The pthread_barrier_init() function allocates any resources required to use
* the barrier referenced by 'barrier' and initialized the barrier with the
* attributes referenced by attr. If attr is NULL, the default barrier
* attributes will be used. The results are undefined if pthread_barrier_init()
* is called when any thread is blocked on the barrier. The results are
* undefined if a barrier is used without first being initialized. The results
* are undefined if pthread_barrier_init() is called specifying an already
* initialized barrier.
*
* Parameters:
* barrier - the barrier to be initialized
* attr - barrier attributes to be used in the initialization.
* count - the count to be associated with the barrier. The count argument
* specifies the number of threads that must call pthread_barrier_wait() before
* any of them successfully return from the call. The value specified by
* count must be greater than zero.
*
* Return Value:
* 0 (OK) on success or on of the following error numbers:
*
* EAGAIN The system lacks the necessary resources to initialize another barrier.
* EINVAL The barrier reference is invalid, or the values specified by attr are
* invalid, or the value specified by count is equal to zero.
* ENOMEM Insufficient memory exists to initialize the barrier.
* EBUSY The implementation has detected an attempt to reinitialize a barrier
* while it is in use.
*
* Assumptions:
*
********************************************************************************/
int pthread_barrier_init(FAR pthread_barrier_t *barrier,
FAR const pthread_barrierattr_t *attr, unsigned int count)
{
int ret = OK;
if (!barrier || count == 0)
{
ret = EINVAL;
}
else
{
sem_init(&barrier->sem, 0, 0);
barrier->count = count;
}
return ret;
}
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