int
_pthread_rwlock_init (pthread_rwlock_t *rwlock, const pthread_rwlockattr_t *attr)
{
pthread_rwlock_t prwlock;
int ret;
/* allocate rwlock object */
prwlock = (pthread_rwlock_t)malloc(sizeof(struct pthread_rwlock));
if (prwlock == NULL)
return(ENOMEM);
/* initialize the lock */
if ((ret = _pthread_mutex_init(&prwlock->lock, NULL)) != 0)
free(prwlock);
else {
/* initialize the read condition signal */
ret = _pthread_cond_init(&prwlock->read_signal, NULL);
if (ret != 0) {
_pthread_mutex_destroy(&prwlock->lock);
free(prwlock);
} else {
/* initialize the write condition signal */
ret = _pthread_cond_init(&prwlock->write_signal, NULL);
if (ret != 0) {
_pthread_cond_destroy(&prwlock->read_signal);
_pthread_mutex_destroy(&prwlock->lock);
free(prwlock);
} else {
/* success */
prwlock->state = 0;
prwlock->blocked_writers = 0;
*rwlock = prwlock;
}
}
}
return (ret);
}
void init_sync(pthread_mutex_t *mutex, pthread_cond_t *cond, pthread_mutex_t *mfinished, pthread_mutex_t *mbank,
pthread_mutex_t *mcur_run, pthread_mutex_t *mhb, pthread_mutex_t *mnr) {
// init synchronization info
_pthread_mutex_init(mutex, NULL);
_pthread_cond_init(cond, NULL);
// service info
_pthread_mutex_init(mfinished, NULL);
_pthread_mutex_init(mbank, NULL);
_pthread_mutex_init(mcur_run, NULL);
_pthread_mutex_init(mhb, NULL);
_pthread_mutex_init(mnr, NULL);
}
int
pthread_cond_init(pthread_cond_t *ocond, const pthread_condattr_t *attr)
{
int conforming;
#if __DARWIN_UNIX03
conforming = 1;
#else /* __DARWIN_UNIX03 */
conforming = 0;
#endif /* __DARWIN_UNIX03 */
_pthread_cond *cond = (_pthread_cond *)ocond;
LOCK_INIT(cond->lock);
return _pthread_cond_init(cond, attr, conforming);
}
static int
_pthread_cond_check_init(_pthread_cond *cond, bool *inited)
{
int res = 0;
if (cond->sig != _PTHREAD_COND_SIG) {
res = EINVAL;
if (cond->sig == _PTHREAD_COND_SIG_init) {
LOCK(cond->lock);
if (cond->sig == _PTHREAD_COND_SIG_init) {
res = _pthread_cond_init(cond, NULL, 0);
if (inited) {
*inited = true;
}
} else if (cond->sig == _PTHREAD_COND_SIG) {
res = 0;
}
UNLOCK(cond->lock);
}
}
return res;
}
static sem_t
sem_alloc(unsigned int value, semid_t semid, int system_sem)
{
sem_t sem;
if (value > SEM_VALUE_MAX) {
errno = EINVAL;
return (NULL);
}
sem = (sem_t)malloc(sizeof(struct sem));
if (sem == NULL) {
errno = ENOSPC;
return (NULL);
}
/*
* Initialize the semaphore.
*/
if (_pthread_mutex_init(&sem->lock, NULL) != 0) {
free(sem);
errno = ENOSPC;
return (NULL);
}
if (_pthread_cond_init(&sem->gtzero, NULL) != 0) {
_pthread_mutex_destroy(&sem->lock);
free(sem);
errno = ENOSPC;
return (NULL);
}
sem->count = (u_int32_t)value;
sem->nwaiters = 0;
sem->magic = SEM_MAGIC;
sem->semid = semid;
sem->syssem = system_sem;
return (sem);
}
int
_pthread_cond_broadcast(pthread_cond_t * cond)
{
struct pthread *curthread = _get_curthread();
struct pthread *pthread;
struct kse_mailbox *kmbx;
int rval = 0;
THR_ASSERT(curthread->locklevel == 0,
"cv_timedwait: locklevel is not zero!");
if (cond == NULL)
rval = EINVAL;
/*
* If the condition variable is statically initialized, perform dynamic
* initialization.
*/
else if (*cond != NULL || (rval = _pthread_cond_init(cond, NULL)) == 0) {
/* Lock the condition variable structure: */
THR_LOCK_ACQUIRE(curthread, &(*cond)->c_lock);
/* Process according to condition variable type: */
switch ((*cond)->c_type) {
/* Fast condition variable: */
case COND_TYPE_FAST:
/* Increment the sequence number: */
(*cond)->c_seqno++;
/*
* Enter a loop to bring all threads off the
* condition queue:
*/
while ((pthread = TAILQ_FIRST(&(*cond)->c_queue))
!= NULL) {
THR_SCHED_LOCK(curthread, pthread);
cond_queue_remove(*cond, pthread);
pthread->sigbackout = NULL;
if ((pthread->kseg == curthread->kseg) &&
(pthread->active_priority >
curthread->active_priority))
curthread->critical_yield = 1;
kmbx = _thr_setrunnable_unlocked(pthread);
THR_SCHED_UNLOCK(curthread, pthread);
if (kmbx != NULL)
kse_wakeup(kmbx);
}
/* There are no more waiting threads: */
(*cond)->c_mutex = NULL;
break;
/* Trap invalid condition variable types: */
default:
/* Return an invalid argument error: */
rval = EINVAL;
break;
}
/* Unlock the condition variable structure: */
THR_LOCK_RELEASE(curthread, &(*cond)->c_lock);
}
/* Return the completion status: */
return (rval);
}
int
_pthread_cond_signal(pthread_cond_t * cond)
{
struct pthread *curthread = _get_curthread();
struct pthread *pthread;
struct kse_mailbox *kmbx;
int rval = 0;
THR_ASSERT(curthread->locklevel == 0,
"cv_timedwait: locklevel is not zero!");
if (cond == NULL)
rval = EINVAL;
/*
* If the condition variable is statically initialized, perform dynamic
* initialization.
*/
else if (*cond != NULL || (rval = _pthread_cond_init(cond, NULL)) == 0) {
/* Lock the condition variable structure: */
THR_LOCK_ACQUIRE(curthread, &(*cond)->c_lock);
/* Process according to condition variable type: */
switch ((*cond)->c_type) {
/* Fast condition variable: */
case COND_TYPE_FAST:
/* Increment the sequence number: */
(*cond)->c_seqno++;
/*
* Wakeups have to be done with the CV lock held;
* otherwise there is a race condition where the
* thread can timeout, run on another KSE, and enter
* another blocking state (including blocking on a CV).
*/
if ((pthread = TAILQ_FIRST(&(*cond)->c_queue))
!= NULL) {
THR_SCHED_LOCK(curthread, pthread);
cond_queue_remove(*cond, pthread);
pthread->sigbackout = NULL;
if ((pthread->kseg == curthread->kseg) &&
(pthread->active_priority >
curthread->active_priority))
curthread->critical_yield = 1;
kmbx = _thr_setrunnable_unlocked(pthread);
THR_SCHED_UNLOCK(curthread, pthread);
if (kmbx != NULL)
kse_wakeup(kmbx);
}
/* Check for no more waiters: */
if (TAILQ_EMPTY(&(*cond)->c_queue))
(*cond)->c_mutex = NULL;
break;
/* Trap invalid condition variable types: */
default:
/* Return an invalid argument error: */
rval = EINVAL;
break;
}
/* Unlock the condition variable structure: */
THR_LOCK_RELEASE(curthread, &(*cond)->c_lock);
}
/* Return the completion status: */
return (rval);
}
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);
}
