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/*
* $Id$
*/
#include <assert.h>
#include <errno.h>
#include <pthread.h>
#include <rtems/system.h>
#include <rtems/score/coremutex.h>
#include <rtems/score/watchdog.h>
#if defined(RTEMS_MULTIPROCESSING)
#include <rtems/score/mpci.h>
#endif
#include <rtems/posix/mutex.h>
#include <rtems/posix/priority.h>
#include <rtems/posix/time.h>
/*PAGE
*
* 11.3.2 Initializing and Destroying a Mutex, P1003.1c/Draft 10, p. 87
*
* NOTE: XXX Could be optimized so all the attribute error checking
* is not performed when attr is NULL.
*/
int pthread_mutex_init(
pthread_mutex_t *mutex,
const pthread_mutexattr_t *attr
)
{
POSIX_Mutex_Control *the_mutex;
CORE_mutex_Attributes *the_mutex_attr;
const pthread_mutexattr_t *the_attr;
CORE_mutex_Disciplines the_discipline;
#if 0
register POSIX_Mutex_Control *mutex_in_use;
Objects_Locations location;
#endif
if ( attr ) the_attr = attr;
else the_attr = &_POSIX_Mutex_Default_attributes;
/* Check for NULL mutex */
if ( !mutex )
return EINVAL;
/*
* This code should eventually be removed.
*
* Although the POSIX specification says:
*
* "Attempting to initialize an already initialized mutex results
* in undefined behavior."
*
* Trying to keep the caller from doing the create when *mutex
* is actually a valid ID causes grief. All it takes is the wrong
* value in an uninitialized variable to make this fail. As best
* I can tell, RTEMS was the only pthread implementation to choose
* this option for "undefined behavior" and doing so has created
* portability problems. In particular, Rosimildo DaSilva
* <rdasilva@connecttel.com> saw seemingly random failures in the
* RTEMS port of omniORB2 when this code was enabled.
*
* Joel Sherrill <joel@OARcorp.com> 14 May 1999
*/
#if 0
/* avoid infinite recursion on call to this routine in _POSIX_Mutex_Get */
if ( *mutex != PTHREAD_MUTEX_INITIALIZER ) {
/* EBUSY if *mutex is a valid id */
mutex_in_use = _POSIX_Mutex_Get( mutex, &location );
switch ( location ) {
case OBJECTS_REMOTE:
case OBJECTS_ERROR:
break;
case OBJECTS_LOCAL:
_Thread_Enable_dispatch();
return EBUSY;
}
}
#endif
if ( !the_attr->is_initialized )
return EINVAL;
/*
* XXX: Be careful about attributes when global!!!
*/
assert( the_attr->process_shared == PTHREAD_PROCESS_PRIVATE );
#if defined(RTEMS_MULTIPROCESSING)
if ( the_attr->process_shared == PTHREAD_PROCESS_SHARED )
return POSIX_MP_NOT_IMPLEMENTED();
#endif
/*
* Determine the discipline of the mutex
*/
switch ( the_attr->protocol ) {
case PTHREAD_PRIO_NONE:
the_discipline = CORE_MUTEX_DISCIPLINES_FIFO;
break;
case PTHREAD_PRIO_INHERIT:
the_discipline = CORE_MUTEX_DISCIPLINES_PRIORITY_INHERIT;
break;
case PTHREAD_PRIO_PROTECT:
the_discipline = CORE_MUTEX_DISCIPLINES_PRIORITY_CEILING;
break;
default:
return EINVAL;
}
if ( !_POSIX_Priority_Is_valid( the_attr->prio_ceiling ) )
return EINVAL;
_Thread_Disable_dispatch();
the_mutex = _POSIX_Mutex_Allocate();
if ( !the_mutex ) {
_Thread_Enable_dispatch();
return EAGAIN;
}
#if defined(RTEMS_MULTIPROCESSING)
if ( the_attr->process_shared == PTHREAD_PROCESS_SHARED &&
!( _Objects_MP_Allocate_and_open( &_POSIX_Mutex_Information, 0,
the_mutex->Object.id, FALSE ) ) ) {
_POSIX_Mutex_Free( the_mutex );
_Thread_Enable_dispatch();
return EAGAIN;
}
#endif
the_mutex->process_shared = the_attr->process_shared;
the_mutex_attr = &the_mutex->Mutex.Attributes;
if ( the_attr->recursive )
the_mutex_attr->lock_nesting_behavior = CORE_MUTEX_NESTING_ACQUIRES;
else
the_mutex_attr->lock_nesting_behavior = CORE_MUTEX_NESTING_IS_ERROR;
the_mutex_attr->only_owner_release = TRUE;
the_mutex_attr->priority_ceiling =
_POSIX_Priority_To_core( the_attr->prio_ceiling );
the_mutex_attr->discipline = the_discipline;
/*
* Must be initialized to unlocked.
*/
_CORE_mutex_Initialize(
&the_mutex->Mutex,
OBJECTS_POSIX_MUTEXES,
the_mutex_attr,
CORE_MUTEX_UNLOCKED,
NULL /* proxy_extract_callout */
);
_Objects_Open( &_POSIX_Mutex_Information, &the_mutex->Object, 0 );
*mutex = the_mutex->Object.id;
#if defined(RTEMS_MULTIPROCESSING)
if ( the_attr->process_shared == PTHREAD_PROCESS_SHARED )
_POSIX_Mutex_MP_Send_process_packet(
POSIX_MUTEX_MP_ANNOUNCE_CREATE,
the_mutex->Object.id,
0, /* Name not used */
0 /* Not used */
);
#endif
_Thread_Enable_dispatch();
return 0;
}
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