/*!
* Unlock mutex object
* \param mutex Mutex descriptor (user level descriptor)
* \return 0 if successful, -1 otherwise and appropriate error number is set
*/
int sys__pthread_mutex_unlock ( void *p )
{
pthread_mutex_t *mutex;
kpthread_mutex_t *kmutex;
kobject_t *kobj;
mutex = *( (pthread_mutex_t **) p );
ASSERT_ERRNO_AND_EXIT ( mutex, EINVAL );
kobj = mutex->ptr;
ASSERT_ERRNO_AND_EXIT ( kobj, EINVAL );
ASSERT_ERRNO_AND_EXIT ( list_find ( &kobjects, &kobj->list ),
EINVAL );
kmutex = kobj->kobject;
ASSERT_ERRNO_AND_EXIT ( kmutex && kmutex->id == mutex->id, EINVAL );
if ( kmutex->owner != kthread_get_active() )
{
SET_ERRNO ( EPERM );
return EXIT_FAILURE;
}
SET_ERRNO ( EXIT_SUCCESS );
kmutex->owner = kthreadq_get ( &kmutex->queue );
if ( kmutex->owner )
{
kthreadq_release ( &kmutex->queue );
kthreads_schedule ();
}
return EXIT_SUCCESS;
}
/*! Unlock device */
int k_device_unlock ( kdevice_t *dev )
{
if ( kthreadq_release ( &dev->thrq ) )
kthreads_schedule ();
else
dev->locked = FALSE;
return 0;
}
/*!
* Release all threads from given queue (if queue not empty)
* \param q Queue
* \return number of thread released, 0 if queue was empty
*/
int kthreadq_release_all ( kthread_q *q )
{
ASSERT ( q );
int cnt = 0;
while ( kthreadq_release (q) )
cnt++;
return cnt;
}
/*!
* Wait on conditional variable
* \param cond conditional variable descriptor (user level descriptor)
* \param mutex Mutex descriptor (user level descriptor)
* \return 0 if successful, -1 otherwise and appropriate error number is set
*/
int sys__pthread_cond_wait ( void *p )
{
pthread_cond_t *cond;
pthread_mutex_t *mutex;
kpthread_cond_t *kcond;
kpthread_mutex_t *kmutex;
kobject_t *kobj_cond, *kobj_mutex;
int retval = EXIT_SUCCESS;
cond = *( (pthread_cond_t **) p ); p += sizeof (pthread_cond_t *);
mutex = *( (pthread_mutex_t **) p );
ASSERT_ERRNO_AND_EXIT ( cond && mutex, EINVAL );
kobj_cond = cond->ptr;
ASSERT_ERRNO_AND_EXIT ( kobj_cond, EINVAL );
ASSERT_ERRNO_AND_EXIT ( list_find ( &kobjects, &kobj_cond->list ),
EINVAL );
kcond = kobj_cond->kobject;
ASSERT_ERRNO_AND_EXIT ( kcond && kcond->id == cond->id, EINVAL );
kobj_mutex = mutex->ptr;
ASSERT_ERRNO_AND_EXIT ( kobj_mutex, EINVAL );
ASSERT_ERRNO_AND_EXIT ( list_find ( &kobjects, &kobj_mutex->list),
EINVAL );
kmutex = kobj_mutex->kobject;
ASSERT_ERRNO_AND_EXIT ( kmutex && kmutex->id == mutex->id, EINVAL );
ASSERT_ERRNO_AND_EXIT ( kmutex->owner == kthread_get_active(), EPERM );
SET_ERRNO ( EXIT_SUCCESS );
/* move thread in conditional variable queue */
kthread_enqueue ( NULL, &kcond->queue, 0, NULL, NULL );
/* save reference to mutex object */
kthread_set_private_param ( NULL, kobj_mutex );
/* release mutex */
kmutex->owner = kthreadq_get ( &kmutex->queue );
if ( kmutex->owner )
kthreadq_release ( &kmutex->queue );
kthreads_schedule ();
return retval;
}
/*!
* Wait on conditional variable
* \param cond conditional variable descriptor (user level descriptor)
* \param mutex Mutex descriptor (user level descriptor)
* \return 0 if successful, -1 otherwise and appropriate error number is set
*/
int sys__pthread_cond_wait ( pthread_cond_t *cond, pthread_mutex_t *mutex )
{
kpthread_cond_t *kcond;
kpthread_mutex_t *kmutex;
kobject_t *kobj_cond, *kobj_mutex;
SYS_ENTRY();
ASSERT_ERRNO_AND_EXIT ( cond && mutex, EINVAL );
kobj_cond = cond->ptr;
ASSERT_ERRNO_AND_EXIT ( kobj_cond, EINVAL );
ASSERT_ERRNO_AND_EXIT ( list_find ( &kobjects, &kobj_cond->list ),
EINVAL );
kcond = kobj_cond->kobject;
ASSERT_ERRNO_AND_EXIT ( kcond && kcond->id == cond->id, EINVAL );
kobj_mutex = mutex->ptr;
ASSERT_ERRNO_AND_EXIT ( kobj_mutex, EINVAL );
ASSERT_ERRNO_AND_EXIT ( list_find ( &kobjects, &kobj_mutex->list),
EINVAL );
kmutex = kobj_mutex->kobject;
ASSERT_ERRNO_AND_EXIT ( kmutex && kmutex->id == mutex->id, EINVAL );
ASSERT_ERRNO_AND_EXIT ( kmutex->owner == kthread_get_active(), EPERM );
kthread_set_errno ( NULL, EXIT_SUCCESS );
kthread_set_syscall_retval ( NULL, EXIT_SUCCESS );
/* move thread in conditional variable queue */
kthread_enqueue ( NULL, &kcond->queue );
/* save reference to mutex object */
kthread_set_private_param ( NULL, kobj_mutex );
/* release mutex */
kmutex->owner = kthreadq_get ( &kmutex->queue );
if ( kmutex->owner )
kthreadq_release ( &kmutex->queue );
kthreads_schedule ();
SYS_EXIT ( kthread_get_errno(NULL), kthread_get_syscall_retval(NULL) );
}
/*!
* Increment (lock) semaphore value by 1 (or unblock one thread that is blocked)
* \param sem Semaphore descriptor (user level descriptor)
* \return 0 if successful, -1 otherwise and appropriate error number is set
*/
int sys__sem_post ( void *p )
{
sem_t *sem;
ksem_t *ksem;
kobject_t *kobj;
kthread_t *kthread, *released;
sem = *( (sem_t **) p );
ASSERT_ERRNO_AND_EXIT ( sem, EINVAL );
kthread = kthread_get_active ();
kobj = sem->ptr;
ASSERT_ERRNO_AND_EXIT ( kobj, EINVAL );
ASSERT_ERRNO_AND_EXIT ( list_find ( &kobjects, &kobj->list ),
EINVAL );
ksem = kobj->kobject;
ASSERT_ERRNO_AND_EXIT ( ksem && ksem->id == sem->id, EINVAL );
kthread_set_errno ( kthread, EXIT_SUCCESS );
released = kthreadq_get ( &ksem->queue ); /* first to release */
if ( !released || ksem->sem_value < 0 )
{
/* if initial semaphore value (set by sem_init) was negative,
* semaphore will not release threads until until its value
* reaches zero (small extension of POSIX semaphore) */
ksem->sem_value++;
}
else {
kthreadq_release ( &ksem->queue );
kthreads_schedule ();
}
return EXIT_SUCCESS;
}
