int
_sigsuspend(const sigset_t *set)
{
struct pthread *curthread = _get_curthread();
sigset_t oldmask, newmask, tempset;
int ret = -1;
if (curthread->attr.flags & PTHREAD_SCOPE_SYSTEM)
return (__sys_sigsuspend(set));
/* Check if a new signal set was provided by the caller: */
if (set != NULL) {
newmask = *set;
SIG_CANTMASK(newmask);
THR_LOCK_SWITCH(curthread);
/* Save current sigmask: */
oldmask = curthread->sigmask;
curthread->oldsigmask = &oldmask;
/* Change the caller's mask: */
curthread->sigmask = newmask;
tempset = curthread->sigpend;
SIGSETNAND(tempset, newmask);
if (SIGISEMPTY(tempset)) {
THR_SET_STATE(curthread, PS_SIGSUSPEND);
/* Wait for a signal: */
_thr_sched_switch_unlocked(curthread);
} else {
curthread->check_pending = 1;
THR_UNLOCK_SWITCH(curthread);
/* check pending signal I can handle: */
_thr_sig_check_pending(curthread);
}
if ((curthread->cancelflags & THR_CANCELLING) != 0)
curthread->oldsigmask = NULL;
else {
THR_ASSERT(curthread->oldsigmask == NULL,
"oldsigmask is not cleared");
}
/* Always return an interrupted error: */
errno = EINTR;
} else {
/* Return an invalid argument error: */
errno = EINVAL;
}
/* Return the completion status: */
return (ret);
}
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");
}
static int
lib_sigtimedwait(const sigset_t *set, siginfo_t *info,
const struct timespec *timeout)
{
struct pthread *curthread = _get_curthread();
int ret = 0;
int i;
struct sigwait_data waitdata;
sigset_t waitset;
kse_critical_t crit;
siginfo_t siginfo;
if (curthread->attr.flags & PTHREAD_SCOPE_SYSTEM) {
if (info == NULL)
info = &siginfo;
return (__sys_sigtimedwait(set, info, timeout));
}
/*
* Initialize the set of signals that will be waited on:
*/
waitset = *set;
/* These signals can't be waited on. */
SIGDELSET(waitset, SIGKILL);
SIGDELSET(waitset, SIGSTOP);
/*
* POSIX says that the _application_ must explicitly install
* a dummy handler for signals that are SIG_IGN in order
* to sigwait on them. Note that SIG_IGN signals are left in
* the mask because a subsequent sigaction could enable an
* ignored signal.
*/
crit = _kse_critical_enter();
KSE_SCHED_LOCK(curthread->kse, curthread->kseg);
for (i = 1; i <= _SIG_MAXSIG; ++i) {
if (SIGISMEMBER(waitset, i) &&
SIGISMEMBER(curthread->sigpend, i)) {
SIGDELSET(curthread->sigpend, i);
siginfo = curthread->siginfo[i - 1];
KSE_SCHED_UNLOCK(curthread->kse,
curthread->kseg);
_kse_critical_leave(crit);
ret = i;
goto OUT;
}
}
curthread->timeout = 0;
curthread->interrupted = 0;
_thr_set_timeout(timeout);
/* Wait for a signal: */
siginfo.si_signo = 0;
waitdata.waitset = &waitset;
waitdata.siginfo = &siginfo;
curthread->data.sigwait = &waitdata;
THR_SET_STATE(curthread, PS_SIGWAIT);
_thr_sched_switch_unlocked(curthread);
/*
* Return the signal number to the caller:
*/
if (siginfo.si_signo > 0) {
ret = siginfo.si_signo;
} else {
if (curthread->interrupted)
errno = EINTR;
else if (curthread->timeout)
errno = EAGAIN;
ret = -1;
}
curthread->timeout = 0;
curthread->interrupted = 0;
/*
* Probably unnecessary, but since it's in a union struct
* we don't know how it could be used in the future.
*/
curthread->data.sigwait = NULL;
OUT:
if (ret > 0 && info != NULL)
*info = siginfo;
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);
}
int
_nanosleep(const struct timespec *time_to_sleep,
struct timespec *time_remaining)
{
struct pthread *curthread = _get_curthread();
int ret = 0;
struct timespec ts, ts1;
struct timespec remaining_time;
struct timespec wakeup_time;
/* Check if the time to sleep is legal: */
if ((time_to_sleep == NULL) || (time_to_sleep->tv_sec < 0) ||
(time_to_sleep->tv_nsec < 0) ||
(time_to_sleep->tv_nsec >= 1000000000)) {
/* Return an EINVAL error : */
errno = EINVAL;
ret = -1;
} else {
if (curthread->attr.flags & PTHREAD_SCOPE_SYSTEM)
return (__sys_nanosleep(time_to_sleep, time_remaining));
KSE_GET_TOD(curthread->kse, &ts);
/* Calculate the time for the current thread to wake up: */
TIMESPEC_ADD(&wakeup_time, &ts, time_to_sleep);
THR_LOCK_SWITCH(curthread);
curthread->interrupted = 0;
curthread->wakeup_time = wakeup_time;
THR_SET_STATE(curthread, PS_SLEEP_WAIT);
/* Reschedule the current thread to sleep: */
_thr_sched_switch_unlocked(curthread);
/* Calculate the remaining time to sleep: */
KSE_GET_TOD(curthread->kse, &ts1);
remaining_time.tv_sec = time_to_sleep->tv_sec
+ ts.tv_sec - ts1.tv_sec;
remaining_time.tv_nsec = time_to_sleep->tv_nsec
+ ts.tv_nsec - ts1.tv_nsec;
/* Check if the nanosecond field has underflowed: */
if (remaining_time.tv_nsec < 0) {
/* Handle the underflow: */
remaining_time.tv_sec -= 1;
remaining_time.tv_nsec += 1000000000;
}
/* Check if the nanosecond field has overflowed: */
else if (remaining_time.tv_nsec >= 1000000000) {
/* Handle the overflow: */
remaining_time.tv_sec += 1;
remaining_time.tv_nsec -= 1000000000;
}
/* Check if the sleep was longer than the required time: */
if (remaining_time.tv_sec < 0) {
/* Reset the time left: */
remaining_time.tv_sec = 0;
remaining_time.tv_nsec = 0;
}
/* Check if the time remaining is to be returned: */
if (time_remaining != NULL) {
/* Return the actual time slept: */
time_remaining->tv_sec = remaining_time.tv_sec;
time_remaining->tv_nsec = remaining_time.tv_nsec;
}
/* Check if the sleep was interrupted: */
if (curthread->interrupted) {
/* Return an EINTR error : */
errno = EINTR;
ret = -1;
}
}
return (ret);
}
int
_pthread_cond_timedwait(pthread_cond_t * cond, pthread_mutex_t * mutex,
const struct timespec * abstime)
{
struct pthread *curthread = _get_curthread();
int rval = 0;
int done = 0;
int mutex_locked = 1;
int seqno;
THR_ASSERT(curthread->locklevel == 0,
"cv_timedwait: locklevel is not zero!");
if (abstime == NULL || abstime->tv_sec < 0 || abstime->tv_nsec < 0 ||
abstime->tv_nsec >= 1000000000)
return (EINVAL);
/*
* If the condition variable is statically initialized, perform dynamic
* initialization.
*/
if (*cond == NULL && (rval = _pthread_cond_init(cond, NULL)) != 0)
return (rval);
if (!_kse_isthreaded())
_kse_setthreaded(1);
/*
* Enter a loop waiting for a condition signal or broadcast
* to wake up this thread. A loop is needed in case the waiting
* thread is interrupted by a signal to execute a signal handler.
* It is not (currently) possible to remain in the waiting queue
* while running a handler. Instead, the thread is interrupted
* and backed out of the waiting queue prior to executing the
* signal handler.
*/
/* Lock the condition variable structure: */
THR_LOCK_ACQUIRE(curthread, &(*cond)->c_lock);
seqno = (*cond)->c_seqno;
do {
/*
* If the condvar was statically allocated, properly
* initialize the tail queue.
*/
if (((*cond)->c_flags & COND_FLAGS_INITED) == 0) {
TAILQ_INIT(&(*cond)->c_queue);
(*cond)->c_flags |= COND_FLAGS_INITED;
}
/* Process according to condition variable type: */
switch ((*cond)->c_type) {
/* Fast condition variable: */
case COND_TYPE_FAST:
if ((mutex == NULL) || (((*cond)->c_mutex != NULL) &&
((*cond)->c_mutex != *mutex))) {
/* Return invalid argument error: */
rval = EINVAL;
} else {
/* Reset the timeout and interrupted flags: */
curthread->timeout = 0;
curthread->interrupted = 0;
/*
* Queue the running thread for the condition
* variable:
*/
cond_queue_enq(*cond, curthread);
/* Unlock the mutex: */
if (mutex_locked &&
((rval = _mutex_cv_unlock(mutex)) != 0)) {
/*
* Cannot unlock the mutex; remove the
* running thread from the condition
* variable queue:
*/
cond_queue_remove(*cond, curthread);
} else {
/* Remember the mutex: */
(*cond)->c_mutex = *mutex;
/*
* Don't unlock the mutex the next
* time through the loop (if the
* thread has to be requeued after
* handling a signal).
*/
mutex_locked = 0;
/*
* This thread is active and is in a
* critical region (holding the cv
* lock); we should be able to safely
* set the state.
*/
THR_SCHED_LOCK(curthread, curthread);
/* Set the wakeup time: */
curthread->wakeup_time.tv_sec =
abstime->tv_sec;
curthread->wakeup_time.tv_nsec =
abstime->tv_nsec;
THR_SET_STATE(curthread, PS_COND_WAIT);
/* Remember the CV: */
curthread->data.cond = *cond;
curthread->sigbackout = cond_wait_backout;
THR_SCHED_UNLOCK(curthread, curthread);
/* Unlock the CV structure: */
THR_LOCK_RELEASE(curthread,
&(*cond)->c_lock);
/* Schedule the next thread: */
_thr_sched_switch(curthread);
/*
* XXX - This really isn't a good check
* since there can be more than one
* thread waiting on the CV. Signals
* sent to threads waiting on mutexes
* or CVs should really be deferred
* until the threads are no longer
* waiting, but POSIX says that signals
* should be sent "as soon as possible".
*/
done = (seqno != (*cond)->c_seqno);
if (done && !THR_IN_CONDQ(curthread)) {
/*
* The thread is dequeued, so
* it is safe to clear these.
*/
curthread->data.cond = NULL;
curthread->sigbackout = NULL;
check_continuation(curthread,
NULL, mutex);
return (_mutex_cv_lock(mutex));
}
/* Relock the CV structure: */
THR_LOCK_ACQUIRE(curthread,
&(*cond)->c_lock);
/*
* Clear these after taking the lock to
* prevent a race condition where a
* signal can arrive before dequeueing
* the thread.
*/
curthread->data.cond = NULL;
curthread->sigbackout = NULL;
done = (seqno != (*cond)->c_seqno);
if (THR_IN_CONDQ(curthread)) {
cond_queue_remove(*cond,
curthread);
/* Check for no more waiters: */
if (TAILQ_EMPTY(&(*cond)->c_queue))
(*cond)->c_mutex = NULL;
}
if (curthread->timeout != 0) {
/* The wait timedout. */
rval = ETIMEDOUT;
}
}
}
break;
/* Trap invalid condition variable types: */
default:
/* Return an invalid argument error: */
rval = EINVAL;
break;
}
check_continuation(curthread, *cond,
mutex_locked ? NULL : mutex);
} while ((done == 0) && (rval == 0));
/* Unlock the condition variable structure: */
THR_LOCK_RELEASE(curthread, &(*cond)->c_lock);
if (mutex_locked == 0)
_mutex_cv_lock(mutex);
/* Return the completion status: */
return (rval);
}
