int _POSIX_Condition_variables_Signal_support(
pthread_cond_t *cond,
bool is_broadcast
)
{
register POSIX_Condition_variables_Control *the_cond;
Objects_Locations location;
Thread_Control *the_thread;
the_cond = _POSIX_Condition_variables_Get( cond, &location );
switch ( location ) {
case OBJECTS_LOCAL:
do {
the_thread = _Thread_queue_Dequeue( &the_cond->Wait_queue );
if ( !the_thread )
the_cond->Mutex = POSIX_CONDITION_VARIABLES_NO_MUTEX;
} while ( is_broadcast && the_thread );
_Thread_Enable_dispatch();
return 0;
#if defined(RTEMS_MULTIPROCESSING)
case OBJECTS_REMOTE:
#endif
case OBJECTS_ERROR:
break;
}
return EINVAL;
}
/**
* 11.4.2 Initializing and Destroying a Condition Variable,
* P1003.1c/Draft 10, p. 87
*/
int pthread_cond_destroy(
pthread_cond_t *cond
)
{
POSIX_Condition_variables_Control *the_cond;
Objects_Locations location;
the_cond = _POSIX_Condition_variables_Get( cond, &location );
switch ( location ) {
case OBJECTS_LOCAL:
if ( _Thread_queue_First( &the_cond->Wait_queue ) ) {
_Thread_Enable_dispatch();
return EBUSY;
}
_Objects_Close(
&_POSIX_Condition_variables_Information,
&the_cond->Object
);
_POSIX_Condition_variables_Free( the_cond );
_Thread_Enable_dispatch();
return 0;
#if defined(RTEMS_MULTIPROCESSING)
case OBJECTS_REMOTE:
#endif
case OBJECTS_ERROR:
break;
}
return EINVAL;
}
/**
* 11.4.2 Initializing and Destroying a Condition Variable,
* P1003.1c/Draft 10, p. 87
*/
int pthread_cond_destroy(
pthread_cond_t *cond
)
{
POSIX_Condition_variables_Control *the_cond;
Objects_Locations location;
_Objects_Allocator_lock();
the_cond = _POSIX_Condition_variables_Get( cond, &location );
switch ( location ) {
case OBJECTS_LOCAL:
if (
_Thread_queue_First(
&the_cond->Wait_queue,
POSIX_CONDITION_VARIABLES_TQ_OPERATIONS
)
) {
_Objects_Put( &the_cond->Object );
_Objects_Allocator_unlock();
return EBUSY;
}
_Objects_Close(
&_POSIX_Condition_variables_Information,
&the_cond->Object
);
_Objects_Put( &the_cond->Object );
_POSIX_Condition_variables_Free( the_cond );
_Objects_Allocator_unlock();
return 0;
#if defined(RTEMS_MULTIPROCESSING)
case OBJECTS_REMOTE:
#endif
case OBJECTS_ERROR:
break;
}
_Objects_Allocator_unlock();
return EINVAL;
}
int _POSIX_Condition_variables_Wait_support(
pthread_cond_t *cond,
pthread_mutex_t *mutex,
const struct timespec *abstime
)
{
POSIX_Condition_variables_Control *the_cond;
Thread_queue_Context queue_context;
int error;
int mutex_error;
Per_CPU_Control *cpu_self;
Thread_Control *executing;
Watchdog_Interval timeout;
bool already_timedout;
TOD_Absolute_timeout_conversion_results status;
if ( mutex == NULL ) {
return EINVAL;
}
the_cond = _POSIX_Condition_variables_Get( cond, &queue_context );
if ( the_cond == NULL ) {
return EINVAL;
}
already_timedout = false;
if ( abstime != NULL ) {
/*
* POSIX requires that blocking calls with timeouts that take
* an absolute timeout must ignore issues with the absolute
* time provided if the operation would otherwise succeed.
* So we check the abstime provided, and hold on to whether it
* is valid or not. If it isn't correct and in the future,
* then we do a polling operation and convert the UNSATISFIED
* status into the appropriate error.
*/
_Assert( the_cond->clock );
status = _TOD_Absolute_timeout_to_ticks(abstime, the_cond->clock, &timeout);
if ( status == TOD_ABSOLUTE_TIMEOUT_INVALID )
return EINVAL;
if ( status == TOD_ABSOLUTE_TIMEOUT_IS_IN_PAST ||
status == TOD_ABSOLUTE_TIMEOUT_IS_NOW ) {
already_timedout = true;
} else {
_Thread_queue_Context_set_relative_timeout( &queue_context, timeout );
}
} else {
_Thread_queue_Context_set_no_timeout( &queue_context );
}
_POSIX_Condition_variables_Acquire_critical( the_cond, &queue_context );
if (
the_cond->mutex != POSIX_CONDITION_VARIABLES_NO_MUTEX
&& the_cond->mutex != *mutex
) {
_POSIX_Condition_variables_Release( the_cond, &queue_context );
return EINVAL;
}
the_cond->mutex = *mutex;
cpu_self = _Thread_Dispatch_disable_critical( &queue_context.Lock_context );
executing = _Per_CPU_Get_executing( cpu_self );
if ( !already_timedout ) {
_Thread_queue_Context_set_expected_level( &queue_context, 2 );
_Thread_queue_Enqueue_critical(
&the_cond->Wait_queue.Queue,
POSIX_CONDITION_VARIABLES_TQ_OPERATIONS,
executing,
STATES_WAITING_FOR_CONDITION_VARIABLE,
&queue_context
);
} else {
_POSIX_Condition_variables_Release( the_cond, &queue_context );
executing->Wait.return_code = STATUS_TIMEOUT;
}
mutex_error = pthread_mutex_unlock( mutex );
if ( mutex_error != 0 ) {
/*
* Historically, we ignored the unlock status since the behavior
* is undefined by POSIX. But GNU/Linux returns EPERM in this
* case, so we follow their lead.
*/
_Assert( mutex_error == EINVAL || mutex_error == EPERM );
_Thread_queue_Extract( executing );
_Thread_Dispatch_enable( cpu_self );
return EPERM;
}
/*
* Switch ourself out because we blocked as a result of the
* _Thread_queue_Enqueue_critical().
*/
_Thread_Dispatch_enable( cpu_self );
error = _POSIX_Get_error_after_wait( executing );
/*
* If the thread is interrupted, while in the thread queue, by
* a POSIX signal, then pthread_cond_wait returns spuriously,
* according to the POSIX standard. It means that pthread_cond_wait
* returns a success status, except for the fact that it was not
* woken up a pthread_cond_signal() or a pthread_cond_broadcast().
*/
if ( error == EINTR ) {
error = 0;
}
/*
* When we get here the dispatch disable level is 0.
*/
mutex_error = pthread_mutex_lock( mutex );
if ( mutex_error != 0 ) {
_Assert( mutex_error == EINVAL );
return EINVAL;
}
return error;
}
int _POSIX_Condition_variables_Wait_support(
pthread_cond_t *cond,
pthread_mutex_t *mutex,
Watchdog_Interval timeout,
bool already_timedout
)
{
POSIX_Condition_variables_Control *the_cond;
POSIX_Mutex_Control *the_mutex;
Objects_Locations location;
int status;
int mutex_status;
Thread_Control *executing;
the_mutex = _POSIX_Mutex_Get( mutex, &location );
if ( !the_mutex ) {
return EINVAL;
}
_Objects_Put_without_thread_dispatch( &the_mutex->Object );
the_cond = _POSIX_Condition_variables_Get( cond, &location );
switch ( location ) {
case OBJECTS_LOCAL:
if ( the_cond->Mutex && ( the_cond->Mutex != *mutex ) ) {
_Objects_Put( &the_cond->Object );
return EINVAL;
}
mutex_status = pthread_mutex_unlock( mutex );
/*
* Historically, we ignored the return code since the behavior
* is undefined by POSIX. But GNU/Linux returns EPERM in this
* case, so we follow their lead.
*/
if ( mutex_status ) {
_Objects_Put( &the_cond->Object );
return EPERM;
}
if ( !already_timedout ) {
the_cond->Mutex = *mutex;
executing = _Thread_Executing;
executing->Wait.return_code = 0;
executing->Wait.id = *cond;
_Thread_queue_Enqueue(
&the_cond->Wait_queue,
executing,
STATES_WAITING_FOR_CONDITION_VARIABLE
| STATES_INTERRUPTIBLE_BY_SIGNAL,
timeout,
ETIMEDOUT
);
_Objects_Put( &the_cond->Object );
/*
* Switch ourself out because we blocked as a result of the
* _Thread_queue_Enqueue.
*/
/*
* If the thread is interrupted, while in the thread queue, by
* a POSIX signal, then pthread_cond_wait returns spuriously,
* according to the POSIX standard. It means that pthread_cond_wait
* returns a success status, except for the fact that it was not
* woken up a pthread_cond_signal or a pthread_cond_broadcast.
*/
status = executing->Wait.return_code;
if ( status == EINTR )
status = 0;
} else {
_Objects_Put( &the_cond->Object );
status = ETIMEDOUT;
}
/*
* When we get here the dispatch disable level is 0.
*/
mutex_status = pthread_mutex_lock( mutex );
if ( mutex_status )
return EINVAL;
return status;
#if defined(RTEMS_MULTIPROCESSING)
case OBJECTS_REMOTE:
#endif
case OBJECTS_ERROR:
break;
}
return EINVAL;
}
int _POSIX_Condition_variables_Wait_support(
pthread_cond_t *cond,
pthread_mutex_t *mutex,
Watchdog_Interval timeout,
bool already_timedout
)
{
register POSIX_Condition_variables_Control *the_cond;
Objects_Locations location;
int status;
int mutex_status;
if ( !_POSIX_Mutex_Get( mutex, &location ) ) {
return EINVAL;
}
_Thread_Unnest_dispatch();
the_cond = _POSIX_Condition_variables_Get( cond, &location );
switch ( location ) {
case OBJECTS_LOCAL:
if ( the_cond->Mutex && ( the_cond->Mutex != *mutex ) ) {
_Thread_Enable_dispatch();
return EINVAL;
}
(void) pthread_mutex_unlock( mutex );
/* XXX ignore this for now since behavior is undefined
if ( mutex_status ) {
_Thread_Enable_dispatch();
return EINVAL;
}
*/
if ( !already_timedout ) {
the_cond->Mutex = *mutex;
_Thread_queue_Enter_critical_section( &the_cond->Wait_queue );
_Thread_Executing->Wait.return_code = 0;
_Thread_Executing->Wait.queue = &the_cond->Wait_queue;
_Thread_Executing->Wait.id = *cond;
_Thread_queue_Enqueue( &the_cond->Wait_queue, timeout );
_Thread_Enable_dispatch();
/*
* Switch ourself out because we blocked as a result of the
* _Thread_queue_Enqueue.
*/
/*
* If the thread is interrupted, while in the thread queue, by
* a POSIX signal, then pthread_cond_wait returns spuriously,
* according to the POSIX standard. It means that pthread_cond_wait
* returns a success status, except for the fact that it was not
* woken up a pthread_cond_signal or a pthread_cond_broadcast.
*/
status = _Thread_Executing->Wait.return_code;
if ( status == EINTR )
status = 0;
} else {
_Thread_Enable_dispatch();
status = ETIMEDOUT;
}
/*
* When we get here the dispatch disable level is 0.
*/
mutex_status = pthread_mutex_lock( mutex );
if ( mutex_status )
return EINVAL;
return status;
#if defined(RTEMS_MULTIPROCESSING)
case OBJECTS_REMOTE:
#endif
case OBJECTS_ERROR:
break;
}
return EINVAL;
}
