int
__pthread_rwlock_timedwrlock (pthread_rwlock_t *rwlock,
const struct timespec *abstime)
{
pthread_descr self;
pthread_extricate_if extr;
if (abstime->tv_nsec < 0 || abstime->tv_nsec >= 1000000000)
return EINVAL;
self = thread_self ();
/* Set up extrication interface */
extr.pu_object = rwlock;
extr.pu_extricate_func = rwlock_wr_extricate_func;
/* Register extrication interface */
__pthread_set_own_extricate_if (self, &extr);
while(1)
{
__pthread_lock (&rwlock->__rw_lock, self);
if (rwlock->__rw_readers == 0 && rwlock->__rw_writer == NULL)
{
rwlock->__rw_writer = self;
__pthread_set_own_extricate_if (self, 0);
__pthread_unlock (&rwlock->__rw_lock);
return 0;
}
/* Suspend ourselves, then try again */
enqueue (&rwlock->__rw_write_waiting, self);
__pthread_unlock (&rwlock->__rw_lock);
/* This is not a cancellation point */
if (timedsuspend (self, abstime) == 0)
{
int was_on_queue;
__pthread_lock (&rwlock->__rw_lock, self);
was_on_queue = remove_from_queue (&rwlock->__rw_write_waiting, self);
__pthread_unlock (&rwlock->__rw_lock);
if (was_on_queue)
{
__pthread_set_own_extricate_if (self, 0);
return ETIMEDOUT;
}
/* Eat the outstanding restart() from the signaller */
suspend (self);
}
}
}
int sem_wait(sem_t * sem)
{
__volatile__ pthread_descr self = thread_self();
pthread_extricate_if extr;
int already_canceled = 0;
int spurious_wakeup_count;
/* Set up extrication interface */
extr.pu_object = sem;
extr.pu_extricate_func = new_sem_extricate_func;
__pthread_lock(&sem->__sem_lock, self);
if (sem->__sem_value > 0) {
sem->__sem_value--;
__pthread_unlock(&sem->__sem_lock);
return 0;
}
/* Register extrication interface */
THREAD_SETMEM(self, p_sem_avail, 0);
__pthread_set_own_extricate_if(self, &extr);
/* Enqueue only if not already cancelled. */
if (!(THREAD_GETMEM(self, p_canceled)
&& THREAD_GETMEM(self, p_cancelstate) == PTHREAD_CANCEL_ENABLE))
enqueue(&sem->__sem_waiting, self);
else
already_canceled = 1;
__pthread_unlock(&sem->__sem_lock);
if (already_canceled) {
__pthread_set_own_extricate_if(self, 0);
__pthread_do_exit(PTHREAD_CANCELED, CURRENT_STACK_FRAME);
}
/* Wait for sem_post or cancellation, or fall through if already canceled */
spurious_wakeup_count = 0;
while (1)
{
suspend(self);
if (THREAD_GETMEM(self, p_sem_avail) == 0
&& (THREAD_GETMEM(self, p_woken_by_cancel) == 0
|| THREAD_GETMEM(self, p_cancelstate) != PTHREAD_CANCEL_ENABLE))
{
/* Count resumes that don't belong to us. */
spurious_wakeup_count++;
continue;
}
break;
}
__pthread_set_own_extricate_if(self, 0);
/* Terminate only if the wakeup came from cancellation. */
/* Otherwise ignore cancellation because we got the semaphore. */
if (THREAD_GETMEM(self, p_woken_by_cancel)
&& THREAD_GETMEM(self, p_cancelstate) == PTHREAD_CANCEL_ENABLE) {
THREAD_SETMEM(self, p_woken_by_cancel, 0);
__pthread_do_exit(PTHREAD_CANCELED, CURRENT_STACK_FRAME);
}
/* We got the semaphore */
return 0;
}
int sem_timedwait(sem_t *sem, const struct timespec *abstime)
{
pthread_descr self = thread_self();
pthread_extricate_if extr;
int already_canceled = 0;
int spurious_wakeup_count;
__pthread_lock(&sem->__sem_lock, self);
if (sem->__sem_value > 0) {
--sem->__sem_value;
__pthread_unlock(&sem->__sem_lock);
return 0;
}
if (abstime->tv_nsec < 0 || abstime->tv_nsec >= 1000000000) {
/* The standard requires that if the function would block and the
time value is illegal, the function returns with an error. */
__pthread_unlock(&sem->__sem_lock);
__set_errno (EINVAL);
return -1;
}
/* Set up extrication interface */
extr.pu_object = sem;
extr.pu_extricate_func = new_sem_extricate_func;
/* Register extrication interface */
THREAD_SETMEM(self, p_sem_avail, 0);
__pthread_set_own_extricate_if(self, &extr);
/* Enqueue only if not already cancelled. */
if (!(THREAD_GETMEM(self, p_canceled)
&& THREAD_GETMEM(self, p_cancelstate) == PTHREAD_CANCEL_ENABLE))
enqueue(&sem->__sem_waiting, self);
else
already_canceled = 1;
__pthread_unlock(&sem->__sem_lock);
if (already_canceled) {
__pthread_set_own_extricate_if(self, 0);
__pthread_do_exit(PTHREAD_CANCELED, CURRENT_STACK_FRAME);
}
spurious_wakeup_count = 0;
while (1)
{
if (timedsuspend(self, abstime) == 0) {
int was_on_queue;
/* __pthread_lock will queue back any spurious restarts that
may happen to it. */
__pthread_lock(&sem->__sem_lock, self);
was_on_queue = remove_from_queue(&sem->__sem_waiting, self);
__pthread_unlock(&sem->__sem_lock);
if (was_on_queue) {
__pthread_set_own_extricate_if(self, 0);
__set_errno (ETIMEDOUT);
return -1;
}
/* Eat the outstanding restart() from the signaller */
suspend(self);
}
if (THREAD_GETMEM(self, p_sem_avail) == 0
&& (THREAD_GETMEM(self, p_woken_by_cancel) == 0
|| THREAD_GETMEM(self, p_cancelstate) != PTHREAD_CANCEL_ENABLE))
{
/* Count resumes that don't belong to us. */
spurious_wakeup_count++;
continue;
}
break;
}
__pthread_set_own_extricate_if(self, 0);
/* Terminate only if the wakeup came from cancellation. */
/* Otherwise ignore cancellation because we got the semaphore. */
if (THREAD_GETMEM(self, p_woken_by_cancel)
&& THREAD_GETMEM(self, p_cancelstate) == PTHREAD_CANCEL_ENABLE) {
THREAD_SETMEM(self, p_woken_by_cancel, 0);
__pthread_do_exit(PTHREAD_CANCELED, CURRENT_STACK_FRAME);
}
/* We got the semaphore */
return 0;
}
int
__pthread_rwlock_timedrdlock (pthread_rwlock_t *rwlock,
const struct timespec *abstime)
{
pthread_descr self = NULL;
pthread_readlock_info *existing;
int out_of_mem, have_lock_already;
pthread_extricate_if extr;
if (abstime->tv_nsec < 0 || abstime->tv_nsec >= 1000000000)
return EINVAL;
have_lock_already = rwlock_have_already(&self, rwlock,
&existing, &out_of_mem);
if (self == NULL)
self = thread_self ();
/* Set up extrication interface */
extr.pu_object = rwlock;
extr.pu_extricate_func = rwlock_rd_extricate_func;
/* Register extrication interface */
__pthread_set_own_extricate_if (self, &extr);
for (;;)
{
__pthread_lock (&rwlock->__rw_lock, self);
if (rwlock_can_rdlock(rwlock, have_lock_already))
break;
enqueue (&rwlock->__rw_read_waiting, self);
__pthread_unlock (&rwlock->__rw_lock);
/* This is not a cancellation point */
if (timedsuspend (self, abstime) == 0)
{
int was_on_queue;
__pthread_lock (&rwlock->__rw_lock, self);
was_on_queue = remove_from_queue (&rwlock->__rw_read_waiting, self);
__pthread_unlock (&rwlock->__rw_lock);
if (was_on_queue)
{
__pthread_set_own_extricate_if (self, 0);
return ETIMEDOUT;
}
/* Eat the outstanding restart() from the signaller */
suspend (self);
}
}
__pthread_set_own_extricate_if (self, 0);
++rwlock->__rw_readers;
__pthread_unlock (&rwlock->__rw_lock);
if (have_lock_already || out_of_mem)
{
if (existing != NULL)
++existing->pr_lock_count;
else
++self->p_untracked_readlock_count;
}
return 0;
}
int __old_sem_wait(old_sem_t * sem)
{
long oldstatus, newstatus;
volatile pthread_descr self = thread_self();
pthread_descr * th;
pthread_extricate_if extr;
/* Set up extrication interface */
extr.pu_object = 0;
extr.pu_extricate_func = old_sem_extricate_func;
while (1) {
/* Register extrication interface */
__pthread_set_own_extricate_if(self, &extr);
do {
oldstatus = sem->sem_status;
if ((oldstatus & 1) && (oldstatus != 1))
newstatus = oldstatus - 2;
else {
newstatus = (long) self;
self->p_nextwaiting = (pthread_descr) oldstatus;
}
}
while (! sem_compare_and_swap(sem, oldstatus, newstatus));
if (newstatus & 1) {
/* We got the semaphore. */
__pthread_set_own_extricate_if(self, 0);
self->p_nextwaiting = NULL;
return 0;
}
/* Wait for sem_post or cancellation */
suspend(self);
__pthread_set_own_extricate_if(self, 0);
/* This is a cancellation point */
if (self->p_canceled && self->p_cancelstate == PTHREAD_CANCEL_ENABLE) {
/* Remove ourselves from the waiting list if we're still on it */
/* First check if we're at the head of the list. */
do {
oldstatus = sem->sem_status;
if (oldstatus != (long) self) break;
newstatus = (long) self->p_nextwaiting;
}
while (! sem_compare_and_swap(sem, oldstatus, newstatus));
/* Now, check if we're somewhere in the list.
There's a race condition with sem_post here, but it does not matter:
the net result is that at the time pthread_exit is called,
self is no longer reachable from sem->sem_status. */
if (oldstatus != (long) self && (oldstatus & 1) == 0) {
for (th = &(((pthread_descr) oldstatus)->p_nextwaiting);
*th != NULL && *th != (pthread_descr) 1;
th = &((*th)->p_nextwaiting)) {
if (*th == self) {
*th = self->p_nextwaiting;
break;
}
}
}
__pthread_do_exit(PTHREAD_CANCELED, CURRENT_STACK_FRAME);
}
}
}
int pthread_join(pthread_t thread_id, void ** thread_return)
{
volatile pthread_descr self = thread_self();
struct pthread_request request;
pthread_handle handle = thread_handle(thread_id);
pthread_descr th;
pthread_extricate_if extr;
int already_canceled = 0;
PDEBUG("\n");
/* Set up extrication interface */
extr.pu_object = handle;
extr.pu_extricate_func = join_extricate_func;
__pthread_lock(&handle->h_lock, self);
if (invalid_handle(handle, thread_id)) {
__pthread_unlock(&handle->h_lock);
return ESRCH;
}
th = handle->h_descr;
if (th == self) {
__pthread_unlock(&handle->h_lock);
return EDEADLK;
}
/* If detached or already joined, error */
if (th->p_detached || th->p_joining != NULL) {
__pthread_unlock(&handle->h_lock);
return EINVAL;
}
/* If not terminated yet, suspend ourselves. */
if (! th->p_terminated) {
/* Register extrication interface */
__pthread_set_own_extricate_if(self, &extr);
if (!(THREAD_GETMEM(self, p_canceled)
&& THREAD_GETMEM(self, p_cancelstate) == PTHREAD_CANCEL_ENABLE))
th->p_joining = self;
else
already_canceled = 1;
__pthread_unlock(&handle->h_lock);
if (already_canceled) {
__pthread_set_own_extricate_if(self, 0);
__pthread_do_exit(PTHREAD_CANCELED, CURRENT_STACK_FRAME);
}
PDEBUG("before suspend\n");
suspend(self);
PDEBUG("after suspend\n");
/* Deregister extrication interface */
__pthread_set_own_extricate_if(self, 0);
/* This is a cancellation point */
if (THREAD_GETMEM(self, p_woken_by_cancel)
&& THREAD_GETMEM(self, p_cancelstate) == PTHREAD_CANCEL_ENABLE) {
THREAD_SETMEM(self, p_woken_by_cancel, 0);
__pthread_do_exit(PTHREAD_CANCELED, CURRENT_STACK_FRAME);
}
__pthread_lock(&handle->h_lock, self);
}
/* Get return value */
if (thread_return != NULL) *thread_return = th->p_retval;
__pthread_unlock(&handle->h_lock);
/* Send notification to thread manager */
if (__pthread_manager_request >= 0) {
request.req_thread = self;
request.req_kind = REQ_FREE;
request.req_args.free.thread_id = thread_id;
TEMP_FAILURE_RETRY(__libc_write(__pthread_manager_request,
(char *) &request, sizeof(request)));
}
return 0;
}
