void _POSIX_Semaphore_Delete(
POSIX_Semaphore_Control *the_semaphore
)
{
if ( !the_semaphore->linked && !the_semaphore->open_count ) {
_Objects_Close( &_POSIX_Semaphore_Information, &the_semaphore->Object );
_CORE_semaphore_Flush(
&the_semaphore->Semaphore,
NULL,
-1
);
_POSIX_Semaphore_Free( the_semaphore );
}
}
/*
* _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_arg,
size_t name_len,
int pshared,
unsigned int value,
POSIX_Semaphore_Control **the_sem
)
{
POSIX_Semaphore_Control *the_semaphore;
CORE_semaphore_Attributes *the_sem_attr;
char *name;
/* Sharing semaphores among processes is not currently supported */
if (pshared != 0)
rtems_set_errno_and_return_minus_one( ENOSYS );
the_semaphore = _POSIX_Semaphore_Allocate_unprotected();
if ( !the_semaphore ) {
rtems_set_errno_and_return_minus_one( ENOSPC );
}
/*
* Make a copy of the user's string for name just in case it was
* dynamically constructed.
*/
if ( name_arg != NULL ) {
name = _Workspace_String_duplicate( name_arg, name_len );
if ( !name ) {
_POSIX_Semaphore_Free( the_semaphore );
rtems_set_errno_and_return_minus_one( ENOMEM );
}
} else {
name = NULL;
}
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
);
*the_sem = the_semaphore;
return 0;
}