int
_sigpending(sigset_t *set)
{
struct pthread *curthread = _get_curthread();
kse_critical_t crit;
sigset_t sigset;
int ret = 0;
/* Check for a null signal set pointer: */
if (set == NULL) {
/* Return an invalid argument: */
ret = EINVAL;
}
else {
if (curthread->attr.flags & PTHREAD_SCOPE_SYSTEM)
return (__sys_sigpending(set));
crit = _kse_critical_enter();
KSE_SCHED_LOCK(curthread->kse, curthread->kseg);
sigset = curthread->sigpend;
KSE_SCHED_UNLOCK(curthread->kse, curthread->kseg);
KSE_LOCK_ACQUIRE(curthread->kse, &_thread_signal_lock);
SIGSETOR(sigset, _thr_proc_sigpending);
KSE_LOCK_RELEASE(curthread->kse, &_thread_signal_lock);
_kse_critical_leave(crit);
*set = sigset;
}
/* Return the completion status: */
return (ret);
}
/*
* Find a thread in the linked list of active threads and add a reference
* to it. Threads with positive reference counts will not be deallocated
* until all references are released.
*/
int
_thr_ref_add(struct pthread *curthread, struct pthread *thread,
int include_dead)
{
kse_critical_t crit;
struct pthread *pthread;
struct kse *curkse;
if (thread == NULL)
/* Invalid thread: */
return (EINVAL);
crit = _kse_critical_enter();
curkse = _get_curkse();
KSE_LOCK_ACQUIRE(curkse, &_thread_list_lock);
pthread = _thr_hash_find(thread);
if (pthread) {
if ((include_dead == 0) &&
((pthread->state == PS_DEAD) ||
((pthread->state == PS_DEADLOCK) ||
((pthread->flags & THR_FLAGS_EXITING) != 0))))
pthread = NULL;
else {
pthread->refcount++;
if (curthread != NULL)
curthread->critical_count++;
}
}
KSE_LOCK_RELEASE(curkse, &_thread_list_lock);
_kse_critical_leave(crit);
/* Return zero if the thread exists: */
return ((pthread != NULL) ? 0 : ESRCH);
}
static void
free_stack(struct pthread_attr *pattr)
{
struct kse *curkse;
kse_critical_t crit;
if ((pattr->flags & THR_STACK_USER) == 0) {
crit = _kse_critical_enter();
curkse = _get_curkse();
KSE_LOCK_ACQUIRE(curkse, &_thread_list_lock);
/* Stack routines don't use malloc/free. */
_thr_stack_free(pattr);
KSE_LOCK_RELEASE(curkse, &_thread_list_lock);
_kse_critical_leave(crit);
}
}
void
_thr_ref_delete(struct pthread *curthread, struct pthread *thread)
{
kse_critical_t crit;
struct kse *curkse;
if (thread != NULL) {
crit = _kse_critical_enter();
curkse = _get_curkse();
KSE_LOCK_ACQUIRE(curkse, &_thread_list_lock);
thread->refcount--;
if (curthread != NULL)
curthread->critical_count--;
if ((thread->refcount == 0) &&
(thread->tlflags & TLFLAGS_GC_SAFE) != 0)
THR_GCLIST_ADD(thread);
KSE_LOCK_RELEASE(curkse, &_thread_list_lock);
_kse_critical_leave(crit);
}
}
void
_pthread_exit(void *status)
{
struct pthread *curthread = _get_curthread();
kse_critical_t crit;
struct kse *curkse;
/* Check if this thread is already in the process of exiting: */
if ((curthread->flags & THR_FLAGS_EXITING) != 0) {
char msg[128];
snprintf(msg, sizeof(msg), "Thread %p has called "
"pthread_exit() from a destructor. POSIX 1003.1 "
"1996 s16.2.5.2 does not allow this!", curthread);
PANIC(msg);
}
/*
* Flag this thread as exiting. Threads should now be prevented
* from joining to this thread.
*/
THR_SCHED_LOCK(curthread, curthread);
curthread->flags |= THR_FLAGS_EXITING;
THR_SCHED_UNLOCK(curthread, curthread);
/*
* To avoid signal-lost problem, if signals had already been
* delivered to us, handle it. we have already set EXITING flag
* so no new signals should be delivered to us.
* XXX this is not enough if signal was delivered just before
* thread called sigprocmask and masked it! in this case, we
* might have to re-post the signal by kill() if the signal
* is targeting process (not for a specified thread).
* Kernel has same signal-lost problem, a signal may be delivered
* to a thread which is on the way to call sigprocmask or thr_exit()!
*/
if (curthread->check_pending)
_thr_sig_check_pending(curthread);
/* Save the return value: */
curthread->ret = status;
while (curthread->cleanup != NULL) {
_pthread_cleanup_pop(1);
}
if (curthread->attr.cleanup_attr != NULL) {
curthread->attr.cleanup_attr(curthread->attr.arg_attr);
}
/* Check if there is thread specific data: */
if (curthread->specific != NULL) {
/* Run the thread-specific data destructors: */
_thread_cleanupspecific();
}
if (!_kse_isthreaded())
exit(0);
crit = _kse_critical_enter();
curkse = _get_curkse();
KSE_LOCK_ACQUIRE(curkse, &_thread_list_lock);
/* Use thread_list_lock */
_thread_active_threads--;
if ((_thread_scope_system <= 0 && _thread_active_threads == 1) ||
(_thread_scope_system > 0 && _thread_active_threads == 0)) {
KSE_LOCK_RELEASE(curkse, &_thread_list_lock);
_kse_critical_leave(crit);
exit(0);
/* Never reach! */
}
KSE_LOCK_RELEASE(curkse, &_thread_list_lock);
/* This thread will never be re-scheduled. */
KSE_LOCK(curkse);
THR_SET_STATE(curthread, PS_DEAD);
_thr_sched_switch_unlocked(curthread);
/* Never reach! */
/* This point should not be reached. */
PANIC("Dead thread has resumed");
}
int
_pthread_join(pthread_t pthread, void **thread_return)
{
struct pthread *curthread = _get_curthread();
void *tmp;
kse_critical_t crit;
int ret = 0;
_thr_cancel_enter(curthread);
/* Check if the caller has specified an invalid thread: */
if (pthread == NULL || pthread->magic != THR_MAGIC) {
/* Invalid thread: */
_thr_cancel_leave(curthread, 1);
return (EINVAL);
}
/* Check if the caller has specified itself: */
if (pthread == curthread) {
/* Avoid a deadlock condition: */
_thr_cancel_leave(curthread, 1);
return (EDEADLK);
}
/*
* Find the thread in the list of active threads or in the
* list of dead threads:
*/
if ((ret = _thr_ref_add(curthread, pthread, /*include dead*/1)) != 0) {
/* Return an error: */
_thr_cancel_leave(curthread, 1);
return (ESRCH);
}
THR_SCHED_LOCK(curthread, pthread);
/* Check if this thread has been detached: */
if ((pthread->attr.flags & PTHREAD_DETACHED) != 0) {
THR_SCHED_UNLOCK(curthread, pthread);
/* Remove the reference and return an error: */
_thr_ref_delete(curthread, pthread);
ret = EINVAL;
} else {
/* Lock the target thread while checking its state. */
if (pthread->state == PS_DEAD) {
/* Return the thread's return value: */
tmp = pthread->ret;
/* Detach the thread. */
pthread->attr.flags |= PTHREAD_DETACHED;
/* Unlock the thread. */
THR_SCHED_UNLOCK(curthread, pthread);
/*
* Remove the thread from the list of active
* threads and add it to the GC list.
*/
crit = _kse_critical_enter();
KSE_LOCK_ACQUIRE(curthread->kse, &_thread_list_lock);
THR_LIST_REMOVE(pthread);
THR_GCLIST_ADD(pthread);
KSE_LOCK_RELEASE(curthread->kse, &_thread_list_lock);
_kse_critical_leave(crit);
/* Remove the reference. */
_thr_ref_delete(curthread, pthread);
if (thread_return != NULL)
*thread_return = tmp;
}
else if (pthread->joiner != NULL) {
/* Unlock the thread and remove the reference. */
THR_SCHED_UNLOCK(curthread, pthread);
_thr_ref_delete(curthread, pthread);
/* Multiple joiners are not supported. */
ret = ENOTSUP;
}
else {
/* Set the running thread to be the joiner: */
pthread->joiner = curthread;
/* Keep track of which thread we're joining to: */
curthread->join_status.thread = pthread;
/* Unlock the thread and remove the reference. */
THR_SCHED_UNLOCK(curthread, pthread);
_thr_ref_delete(curthread, pthread);
THR_SCHED_LOCK(curthread, curthread);
while (curthread->join_status.thread == pthread) {
THR_SET_STATE(curthread, PS_JOIN);
THR_SCHED_UNLOCK(curthread, curthread);
/* Schedule the next thread: */
_thr_sched_switch(curthread);
THR_SCHED_LOCK(curthread, curthread);
}
THR_SCHED_UNLOCK(curthread, curthread);
if ((curthread->cancelflags & THR_CANCELLING) &&
!(curthread->cancelflags & PTHREAD_CANCEL_DISABLE)) {
if (_thr_ref_add(curthread, pthread, 1) == 0) {
THR_SCHED_LOCK(curthread, pthread);
pthread->joiner = NULL;
THR_SCHED_UNLOCK(curthread, pthread);
_thr_ref_delete(curthread, pthread);
}
_pthread_exit(PTHREAD_CANCELED);
}
/*
* The thread return value and error are set by the
* thread we're joining to when it exits or detaches:
*/
ret = curthread->join_status.error;
if ((ret == 0) && (thread_return != NULL))
*thread_return = curthread->join_status.ret;
}
}
_thr_cancel_leave(curthread, 1);
/* Return the completion status: */
return (ret);
}
