source: trunk/sys/libpthread/semaphore.c @ 50

/*
 * semaphore.c - semaphore related system calls
 * 
 * Author  Ghassan Almaless  (2008,2009,2010,2011,2012)
 *         Alain Greiner     (2016)
 *
 * Copyright (c)  UPMC Sorbonne Universites
 *
 * This file is part of ALMOS-MKH.
 *
 * ALMOS-MKH.is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by
 * the Free Software Foundation; version 2.0 of the License.
 *
 * ALMOS-MKH.is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with ALMOS-MKH.; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
 */

#include <errno.h>
#include <sys/types.h>
#include <semaphore.h>
#include <sys/syscall.h>
#include <cpu-syscall.h>

typedef enum
{
        SEM_INIT,
        SEM_GETVALUE,
        SEM_WAIT,
        SEM_POST,
        SEM_DESTROY
} 
sem_operation_t;

///////////////////////////////////////////////////////////////////////////////////////////////
static int __sys_sem( sem_t *sem, int operation, int pshared, int *value)
{
        register int retval;
  
        retval = (int)cpu_syscall( (void*)sem,
                               (void*)operation,
                               (void*)pshared,
                               (void*)value,
                               SYS_SEMAPHORE );
        return retval;
}

///////////////////////////////
int sem_init( sem_t      * sem, 
              int          pshared, 
              unsigned int value)
{
        int v          = (int)value;
        int *value_ptr = &v;

        return __sys_sem(sem, SEM_INIT, pshared, value_ptr);
}

//////////////////////////////
int sem_getvalue( sem_t * sem,
                  int   * value )
{
        return __sys_sem(sem, SEM_GETVALUE, 0, value);
}

///////////////////////////
int sem_wait( sem_t * sem )
{
        return __sys_sem(sem, SEM_WAIT, 0, NULL);
}

///////////////////////////
int sem_post( sem_t * sem )
{
        return __sys_sem(sem, SEM_POST, 0, NULL);
}

//////////////////////////////
int sem_destroy( sem_t * sem )
{
        return __sys_sem(sem, SEM_DESTROY, 0, NULL);
}