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/************************************************************
* sem_init.c
*
* Copyright (C) 2007 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <spudmonkey@racsa.co.cr>
*
* 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 Gregory Nutt 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 <sys/types.h>
#include <semaphore.h>
#include "sem_internal.h"
/************************************************************
* Compilation Switches
************************************************************/
/************************************************************
* Definitions
************************************************************/
/************************************************************
* Private Type Declarations
************************************************************/
/************************************************************
* Global Variables
************************************************************/
/************************************************************
* Private Variables
************************************************************/
/************************************************************
* Private Functions
************************************************************/
/************************************************************
* Public Functions
************************************************************/
/************************************************************
* Function: sem_init
*
* Description:
* This function initializes the UNAMED semaphore sem.
* Following a successful call to sem_init(), the
* semaophore may be used in subsequent calls to
* sem_wait(), sem_post(), and sem_trywait(). The
* semaphore remains usable until it is destroyed.
*
* Only sem itself may be used for performing
* synchronization. The result of referring to copies of
* sem in calls to sem_wait(), sem_trywait(), sem_post(),
* and sem_destroy() is undefined.
*
* Parameters:
* sem - Semaphore to be initialized
* pshared - Process sharing (not used)
* value - Semaphore initialization value
*
* Return Value:
* 0 (OK), or -1 (ERROR) if unsuccessful.
*
* Assumptions:
*
************************************************************/
int sem_init (sem_t *sem, int pshared, unsigned int value)
{
int ret = ERROR;
if (sem && value <= SEM_MAX_VALUE)
{
sem->semcount = (sint16)value;
ret = OK;
}
return ret;
}
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