int
_pthread_detach(pthread_t pthread)
{
struct pthread *curthread = tls_get_curthread();
int rval;
if (pthread == NULL)
return (EINVAL);
THREAD_LIST_LOCK(curthread);
if ((rval = _thr_find_thread(curthread, pthread,
/*include dead*/1)) != 0) {
THREAD_LIST_UNLOCK(curthread);
return (rval);
}
/* Check if the thread is already detached or has a joiner. */
if ((pthread->tlflags & TLFLAGS_DETACHED) != 0 ||
(pthread->joiner != NULL)) {
THREAD_LIST_UNLOCK(curthread);
return (EINVAL);
}
/* Flag the thread as detached. */
pthread->tlflags |= TLFLAGS_DETACHED;
if (pthread->state == PS_DEAD)
THR_GCLIST_ADD(pthread);
THREAD_LIST_UNLOCK(curthread);
return (0);
}
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);
}
}
static int
join_common(pthread_t pthread, void **thread_return,
const struct timespec *abstime)
{
struct pthread *curthread = tls_get_curthread();
struct timespec ts, ts2, *tsp;
void *tmp;
long state;
int oldcancel;
int ret = 0;
if (pthread == NULL)
return (EINVAL);
if (pthread == curthread)
return (EDEADLK);
THREAD_LIST_LOCK(curthread);
if ((ret = _thr_find_thread(curthread, pthread, 1)) != 0) {
ret = ESRCH;
} else if ((pthread->tlflags & TLFLAGS_DETACHED) != 0) {
ret = ESRCH;
} else if (pthread->joiner != NULL) {
/* Multiple joiners are not supported. */
ret = ENOTSUP;
}
if (ret) {
THREAD_LIST_UNLOCK(curthread);
return (ret);
}
/* Set the running thread to be the joiner: */
pthread->joiner = curthread;
THREAD_LIST_UNLOCK(curthread);
THR_CLEANUP_PUSH(curthread, backout_join, pthread);
oldcancel = _thr_cancel_enter(curthread);
while ((state = pthread->state) != PS_DEAD) {
if (abstime != NULL) {
clock_gettime(CLOCK_REALTIME, &ts);
TIMESPEC_SUB(&ts2, abstime, &ts);
if (ts2.tv_sec < 0) {
ret = ETIMEDOUT;
break;
}
tsp = &ts2;
} else
tsp = NULL;
ret = _thr_umtx_wait(&pthread->state, state, tsp,
CLOCK_REALTIME);
if (ret == ETIMEDOUT)
break;
}
_thr_cancel_leave(curthread, oldcancel);
THR_CLEANUP_POP(curthread, 0);
if (ret == ETIMEDOUT) {
THREAD_LIST_LOCK(curthread);
pthread->joiner = NULL;
THREAD_LIST_UNLOCK(curthread);
} else {
ret = 0;
tmp = pthread->ret;
THREAD_LIST_LOCK(curthread);
pthread->tlflags |= TLFLAGS_DETACHED;
pthread->joiner = NULL;
THR_GCLIST_ADD(pthread);
THREAD_LIST_UNLOCK(curthread);
if (thread_return != NULL)
*thread_return = tmp;
}
return (ret);
}
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);
}
void
_pthread_exit(void *status)
{
struct pthread *curthread = _get_curthread();
/* Check if this thread is already in the process of exiting: */
if (curthread->cancelling) {
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. */
curthread->cancelling = 1;
_thr_exit_cleanup();
/* Save the return value: */
curthread->ret = status;
while (curthread->cleanup != NULL) {
_pthread_cleanup_pop(1);
}
/* Check if there is thread specific data: */
if (curthread->specific != NULL) {
/* Run the thread-specific data destructors: */
_thread_cleanupspecific();
}
if (!_thr_isthreaded())
exit(0);
THREAD_LIST_LOCK(curthread);
_thread_active_threads--;
if (_thread_active_threads == 0) {
THREAD_LIST_UNLOCK(curthread);
exit(0);
/* Never reach! */
}
THREAD_LIST_UNLOCK(curthread);
/* Tell malloc that the thread is exiting. */
_malloc_thread_cleanup();
THREAD_LIST_LOCK(curthread);
THR_LOCK(curthread);
curthread->state = PS_DEAD;
if (curthread->flags & THR_FLAGS_NEED_SUSPEND) {
curthread->cycle++;
_thr_umtx_wake(&curthread->cycle, INT_MAX, 0);
}
THR_UNLOCK(curthread);
/*
* Thread was created with initial refcount 1, we drop the
* reference count to allow it to be garbage collected.
*/
curthread->refcount--;
if (curthread->tlflags & TLFLAGS_DETACHED)
THR_GCLIST_ADD(curthread);
THREAD_LIST_UNLOCK(curthread);
if (!curthread->force_exit && SHOULD_REPORT_EVENT(curthread, TD_DEATH))
_thr_report_death(curthread);
/*
* Kernel will do wakeup at the address, so joiner thread
* will be resumed if it is sleeping at the address.
*/
thr_exit(&curthread->tid);
#ifndef __AVM2__ // might exit if we're impersonating another thread!
PANIC("thr_exit() returned");
#endif
/* Never reach! */
}
