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/*
* COPYRIGHT (c) 1989-2009.
* On-Line Applications Research Corporation (OAR).
*
* The license and distribution terms for this file may be
* found in the file LICENSE in this distribution or at
* http://www.rtems.com/license/LICENSE.
*
* $Id$
*/
#if HAVE_CONFIG_H
#include "config.h"
#endif
#include <stdarg.h>
#include <errno.h>
#include <fcntl.h>
#include <pthread.h>
#include <semaphore.h>
#include <limits.h>
#include <string.h> /* strlen */
#include <rtems/system.h>
#include <rtems/score/object.h>
#include <rtems/posix/semaphore.h>
#include <rtems/posix/time.h>
#include <rtems/seterr.h>
/* pure ANSI mode does not have this prototype */
size_t strnlen(const char *, size_t);
/*
* _POSIX_Semaphore_Create_support
*
* This routine does the actual creation and initialization of
* a poxix semaphore. It is a support routine for sem_init and
* sem_open.
*/
int _POSIX_Semaphore_Create_support(
const char *name,
int pshared,
unsigned int value,
POSIX_Semaphore_Control **the_sem
)
{
POSIX_Semaphore_Control *the_semaphore;
CORE_semaphore_Attributes *the_sem_attr;
char *name_p = (char *)name;
/* Sharing semaphores among processes is not currently supported */
if (pshared != 0)
rtems_set_errno_and_return_minus_one( ENOSYS );
if ( name ) {
if ( strnlen( name, NAME_MAX ) >= NAME_MAX )
rtems_set_errno_and_return_minus_one( ENAMETOOLONG );
}
_Thread_Disable_dispatch();
the_semaphore = _POSIX_Semaphore_Allocate();
if ( !the_semaphore ) {
_Thread_Enable_dispatch();
rtems_set_errno_and_return_minus_one( ENOSPC );
}
the_semaphore->process_shared = pshared;
if ( name ) {
the_semaphore->named = true;
the_semaphore->open_count = 1;
the_semaphore->linked = true;
} else {
the_semaphore->named = false;
the_semaphore->open_count = 0;
the_semaphore->linked = false;
}
the_sem_attr = &the_semaphore->Semaphore.Attributes;
/*
* POSIX does not appear to specify what the discipline for
* blocking tasks on this semaphore should be. It could somehow
* be derived from the current scheduling policy. One
* thing is certain, no matter what we decide, it won't be
* the same as all other POSIX implementations. :)
*/
the_sem_attr->discipline = CORE_SEMAPHORE_DISCIPLINES_FIFO;
/*
* This effectively disables limit checking.
*/
the_sem_attr->maximum_count = 0xFFFFFFFF;
_CORE_semaphore_Initialize( &the_semaphore->Semaphore, the_sem_attr, value );
/*
* Make the semaphore available for use.
*/
_Objects_Open_string(
&_POSIX_Semaphore_Information,
&the_semaphore->Object,
name_p
);
*the_sem = the_semaphore;
_Thread_Enable_dispatch();
return 0;
}
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