void
flockfile(FILE * fp)
{
int idx = file_idx(fp);
struct file_lock *p;
/* Lock the hash table: */
_SPINLOCK(&hash_lock);
/* Check if the static array has not been initialised: */
if (!init_done) {
/* Initialise the global array: */
memset(flh,0,sizeof(flh));
/* Flag the initialisation as complete: */
init_done = 1;
}
/* Get a pointer to any existing lock for the file: */
if ((p = find_lock(idx, fp)) == NULL) {
/*
* The file is not locked, so this thread can
* grab the lock:
*/
p = do_lock(idx, fp);
/* Unlock the hash table: */
_SPINUNLOCK(&hash_lock);
/*
* The file is already locked, so check if the
* running thread is the owner:
*/
} else if (p->owner == _thread_run) {
/*
* The running thread is already the
* owner, so increment the count of
* the number of times it has locked
* the file:
*/
p->count++;
/* Unlock the hash table: */
_SPINUNLOCK(&hash_lock);
} else {
/*
* The file is locked for another thread.
* Append this thread to the queue of
* threads waiting on the lock.
*/
TAILQ_INSERT_TAIL(&p->l_head,_thread_run,qe);
/* Unlock the hash table: */
_SPINUNLOCK(&hash_lock);
/* Wait on the FILE lock: */
_thread_kern_sched_state(PS_FILE_WAIT, "", 0);
}
}
void
_mutex_lock_backout(pthread_t pthread)
{
struct pthread_mutex *mutex;
/*
* Defer signals to protect the scheduling queues from
* access by the signal handler:
*/
_thread_kern_sig_defer();
if ((pthread->flags & PTHREAD_FLAGS_IN_MUTEXQ) != 0) {
mutex = pthread->data.mutex;
/* Lock the mutex structure: */
_SPINLOCK(&mutex->lock);
mutex_queue_remove(mutex, pthread);
/* This thread is no longer waiting for the mutex: */
pthread->data.mutex = NULL;
/* Unlock the mutex structure: */
_SPINUNLOCK(&mutex->lock);
}
/*
* Undefer and handle pending signals, yielding if
* necessary:
*/
_thread_kern_sig_undefer();
}
int
close(int fd)
{
int ret;
/* This is a cancelation point: */
_thread_enter_cancellation_point();
if ((fd < 0) || (fd >= _thread_max_fdtsize) ||
(fd == _thread_kern_pipe[0]) || (fd == _thread_kern_pipe[1])) {
errno = EBADF;
ret = -1;
} else if ((ret = _FD_LOCK(fd, FD_RDWR_CLOSE, NULL)) != -1) {
/*
* We need to hold the entry spinlock till after
* _thread_sys_close() to stop races caused by the
* fd state transition.
*/
_SPINLOCK(&_thread_fd_table[fd]->lock);
_thread_fd_entry_close(fd);
/* Close the file descriptor: */
ret = _thread_sys_close(fd);
_SPINUNLOCK(&_thread_fd_table[fd]->lock);
_FD_UNLOCK(fd, FD_RDWR_CLOSE);
}
/* No longer in a cancellation point: */
_thread_leave_cancellation_point();
return (ret);
}
/*
* This function is called when a change in base priority occurs for
* a thread that is holding or waiting for a priority protection or
* inheritence mutex. A change in a threads base priority can effect
* changes to active priorities of other threads and to the ordering
* of mutex locking by waiting threads.
*
* This must be called while thread scheduling is deferred.
*/
void
_mutex_notify_priochange(pthread_t pthread)
{
/* Adjust the priorites of any owned priority mutexes: */
if (pthread->priority_mutex_count > 0) {
/*
* Rescan the mutexes owned by this thread and correct
* their priorities to account for this threads change
* in priority. This has the side effect of changing
* the threads active priority.
*/
mutex_rescan_owned(pthread, /* rescan all owned */ NULL);
}
/*
* If this thread is waiting on a priority inheritence mutex,
* check for priority adjustments. A change in priority can
* also effect a ceiling violation(*) for a thread waiting on
* a priority protection mutex; we don't perform the check here
* as it is done in pthread_mutex_unlock.
*
* (*) It should be noted that a priority change to a thread
* _after_ taking and owning a priority ceiling mutex
* does not affect ownership of that mutex; the ceiling
* priority is only checked before mutex ownership occurs.
*/
if (pthread->state == PS_MUTEX_WAIT) {
/* Lock the mutex structure: */
_SPINLOCK(&pthread->data.mutex->lock);
/*
* Check to make sure this thread is still in the same state
* (the spinlock above can yield the CPU to another thread):
*/
if (pthread->state == PS_MUTEX_WAIT) {
/*
* Remove and reinsert this thread into the list of
* waiting threads to preserve decreasing priority
* order.
*/
mutex_queue_remove(pthread->data.mutex, pthread);
mutex_queue_enq(pthread->data.mutex, pthread);
if (pthread->data.mutex->m_protocol ==
PTHREAD_PRIO_INHERIT) {
/* Adjust priorities: */
mutex_priority_adjust(pthread->data.mutex);
}
}
/* Unlock the mutex structure: */
_SPINUNLOCK(&pthread->data.mutex->lock);
}
}
/*
* quick_exit:
*
* Abandon a process. Execute all quick_exit handlers.
*/
void
quick_exit(int status)
{
struct quick_exit_fn *fn;
if (__isthreaded)
_SPINLOCK(&quick_exit_spinlock);
for (fn = quick_exit_fns; fn != NULL; fn = fn->next) {
fn->func();
}
if (__isthreaded)
_SPINUNLOCK(&quick_exit_spinlock);
_exit(status);
}
int
ftrylockfile(FILE * fp)
{
int ret = -1;
int idx = file_idx(fp);
struct file_lock *p;
/* Lock the hash table: */
_SPINLOCK(&hash_lock);
/* Get a pointer to any existing lock for the file: */
if ((p = find_lock(idx, fp)) == NULL) {
/*
* The file is not locked, so this thread can
* grab the lock:
*/
p = do_lock(idx, fp);
/*
* The file is already locked, so check if the
* running thread is the owner:
*/
} else if (p->owner == _thread_run) {
/*
* The running thread is already the
* owner, so increment the count of
* the number of times it has locked
* the file:
*/
p->count++;
} else {
/*
* The file is locked for another thread,
* so this try fails.
*/
p = NULL;
}
/* Check if the lock was obtained: */
if (p != NULL)
/* Return success: */
ret = 0;
/* Unlock the hash table: */
_SPINUNLOCK(&hash_lock);
return (ret);
}
static int
init_static(pthread_mutex_t *mutex)
{
int ret;
_SPINLOCK(&static_init_lock);
if (*mutex == NULL)
ret = pthread_mutex_init(mutex, NULL);
else
ret = 0;
_SPINUNLOCK(&static_init_lock);
return(ret);
}
/*
* Fake up a minimal siginfo_t for the given signal unless one is already
* pending. The signal number is assumed to be valid.
*/
void
_thread_kill_siginfo(int sig)
{
struct sigstatus *ss = &_thread_sigq[sig - 1];
_SPINLOCK(&ss->lock);
if (ss->pending == 0) {
ss->pending = 1;
memset(&ss->siginfo, 0, sizeof ss->siginfo);
ss->siginfo.si_signo = sig;
ss->siginfo.si_code = SI_USER;
ss->siginfo.si_errno = errno;
ss->siginfo.si_pid = getpid();
}
_SPINUNLOCK(&ss->lock);
}
static int
init_static (pthread_rwlock_t *rwlock)
{
int ret;
_SPINLOCK(&static_init_lock);
if (*rwlock == NULL)
ret = _pthread_rwlock_init(rwlock, NULL);
else
ret = 0;
_SPINUNLOCK(&static_init_lock);
return (ret);
}
int
_pthread_mutex_destroy(pthread_mutex_t * mutex)
{
int ret = 0;
if (mutex == NULL || *mutex == NULL)
ret = EINVAL;
else {
/* Lock the mutex structure: */
_SPINLOCK(&(*mutex)->lock);
/*
* Check to see if this mutex is in use:
*/
if (((*mutex)->m_owner != NULL) ||
(TAILQ_FIRST(&(*mutex)->m_queue) != NULL) ||
((*mutex)->m_refcount != 0)) {
ret = EBUSY;
/* Unlock the mutex structure: */
_SPINUNLOCK(&(*mutex)->lock);
}
else {
/*
* Free the memory allocated for the mutex
* structure:
*/
_MUTEX_ASSERT_NOT_OWNED(*mutex);
free(*mutex);
/*
* Leave the caller's pointer NULL now that
* the mutex has been destroyed:
*/
*mutex = NULL;
}
}
/* Return the completion status: */
return (ret);
}
void
_cond_wait_backout(pthread_t pthread)
{
pthread_cond_t cond;
cond = pthread->data.cond;
if (cond != NULL) {
/*
* Defer signals to protect the scheduling queues
* from access by the signal handler:
*/
_thread_kern_sig_defer();
/* Lock the condition variable structure: */
_SPINLOCK(&cond->lock);
/* Process according to condition variable type: */
switch (cond->c_type) {
/* Fast condition variable: */
case COND_TYPE_FAST:
cond_queue_remove(cond, pthread);
/* Check for no more waiters: */
if (TAILQ_FIRST(&cond->c_queue) == NULL)
cond->c_mutex = NULL;
break;
default:
break;
}
/* Unlock the condition variable structure: */
_SPINUNLOCK(&cond->lock);
/*
* Undefer and handle pending signals, yielding if
* necessary:
*/
_thread_kern_sig_undefer();
}
}
/*
* at_quick_exit:
*
* Register a function to be called at quick_exit.
*/
int
at_quick_exit(void (*func)(void))
{
struct quick_exit_fn *fn;
fn = malloc(sizeof(struct quick_exit_fn));
if (!fn)
return (-1);
fn->func = func;
if (__isthreaded)
_SPINLOCK(&quick_exit_spinlock);
fn->next = quick_exit_fns;
quick_exit_fns = fn;
if (__isthreaded)
_SPINUNLOCK(&quick_exit_spinlock);
return (0);
}
static inline int
mutex_unlock_common(pthread_mutex_t * mutex, int add_reference)
{
struct pthread *curthread = _get_curthread();
int ret = 0;
if (mutex == NULL || *mutex == NULL) {
ret = EINVAL;
} else {
/*
* Defer signals to protect the scheduling queues from
* access by the signal handler:
*/
_thread_kern_sig_defer();
/* Lock the mutex structure: */
_SPINLOCK(&(*mutex)->lock);
/* Process according to mutex type: */
switch ((*mutex)->m_protocol) {
/* Default POSIX mutex: */
case PTHREAD_PRIO_NONE:
/*
* Check if the running thread is not the owner of the
* mutex:
*/
if ((*mutex)->m_owner != curthread) {
/*
* Return an invalid argument error for no
* owner and a permission error otherwise:
*/
ret = (*mutex)->m_owner == NULL ? EINVAL : EPERM;
}
else if (((*mutex)->m_type == PTHREAD_MUTEX_RECURSIVE) &&
((*mutex)->m_data.m_count > 0)) {
/* Decrement the count: */
(*mutex)->m_data.m_count--;
} else {
/*
* Clear the count in case this is recursive
* mutex.
*/
(*mutex)->m_data.m_count = 0;
/* Remove the mutex from the threads queue. */
_MUTEX_ASSERT_IS_OWNED(*mutex);
TAILQ_REMOVE(&(*mutex)->m_owner->mutexq,
(*mutex), m_qe);
_MUTEX_INIT_LINK(*mutex);
/*
* Get the next thread from the queue of
* threads waiting on the mutex:
*/
if (((*mutex)->m_owner =
mutex_queue_deq(*mutex)) != NULL) {
/* Make the new owner runnable: */
PTHREAD_NEW_STATE((*mutex)->m_owner,
PS_RUNNING);
/*
* Add the mutex to the threads list of
* owned mutexes:
*/
TAILQ_INSERT_TAIL(&(*mutex)->m_owner->mutexq,
(*mutex), m_qe);
/*
* The owner is no longer waiting for
* this mutex:
*/
(*mutex)->m_owner->data.mutex = NULL;
}
}
break;
/* POSIX priority inheritence mutex: */
case PTHREAD_PRIO_INHERIT:
/*
* Check if the running thread is not the owner of the
* mutex:
*/
if ((*mutex)->m_owner != curthread) {
/*
* Return an invalid argument error for no
* owner and a permission error otherwise:
*/
ret = (*mutex)->m_owner == NULL ? EINVAL : EPERM;
}
else if (((*mutex)->m_type == PTHREAD_MUTEX_RECURSIVE) &&
((*mutex)->m_data.m_count > 0)) {
/* Decrement the count: */
(*mutex)->m_data.m_count--;
} else {
/*
* Clear the count in case this is recursive
* mutex.
*/
(*mutex)->m_data.m_count = 0;
/*
* Restore the threads inherited priority and
* recompute the active priority (being careful
* not to override changes in the threads base
* priority subsequent to locking the mutex).
*/
curthread->inherited_priority =
(*mutex)->m_saved_prio;
curthread->active_priority =
MAX(curthread->inherited_priority,
curthread->base_priority);
/*
* This thread now owns one less priority mutex.
*/
curthread->priority_mutex_count--;
/* Remove the mutex from the threads queue. */
_MUTEX_ASSERT_IS_OWNED(*mutex);
TAILQ_REMOVE(&(*mutex)->m_owner->mutexq,
(*mutex), m_qe);
_MUTEX_INIT_LINK(*mutex);
/*
* Get the next thread from the queue of threads
* waiting on the mutex:
*/
if (((*mutex)->m_owner =
mutex_queue_deq(*mutex)) == NULL)
/* This mutex has no priority. */
(*mutex)->m_prio = 0;
else {
/*
* Track number of priority mutexes owned:
*/
(*mutex)->m_owner->priority_mutex_count++;
/*
* Add the mutex to the threads list
* of owned mutexes:
*/
TAILQ_INSERT_TAIL(&(*mutex)->m_owner->mutexq,
(*mutex), m_qe);
/*
* The owner is no longer waiting for
* this mutex:
*/
(*mutex)->m_owner->data.mutex = NULL;
/*
* Set the priority of the mutex. Since
* our waiting threads are in descending
* priority order, the priority of the
* mutex becomes the active priority of
* the thread we just dequeued.
*/
(*mutex)->m_prio =
(*mutex)->m_owner->active_priority;
/*
* Save the owning threads inherited
* priority:
*/
(*mutex)->m_saved_prio =
(*mutex)->m_owner->inherited_priority;
/*
* The owning threads inherited priority
* now becomes his active priority (the
* priority of the mutex).
*/
(*mutex)->m_owner->inherited_priority =
(*mutex)->m_prio;
/*
* Make the new owner runnable:
*/
PTHREAD_NEW_STATE((*mutex)->m_owner,
PS_RUNNING);
}
}
break;
/* POSIX priority ceiling mutex: */
case PTHREAD_PRIO_PROTECT:
/*
* Check if the running thread is not the owner of the
* mutex:
*/
if ((*mutex)->m_owner != curthread) {
/*
* Return an invalid argument error for no
* owner and a permission error otherwise:
*/
ret = (*mutex)->m_owner == NULL ? EINVAL : EPERM;
}
else if (((*mutex)->m_type == PTHREAD_MUTEX_RECURSIVE) &&
((*mutex)->m_data.m_count > 0)) {
/* Decrement the count: */
(*mutex)->m_data.m_count--;
} else {
/*
* Clear the count in case this is recursive
* mutex.
*/
(*mutex)->m_data.m_count = 0;
/*
* Restore the threads inherited priority and
* recompute the active priority (being careful
* not to override changes in the threads base
* priority subsequent to locking the mutex).
*/
curthread->inherited_priority =
(*mutex)->m_saved_prio;
curthread->active_priority =
MAX(curthread->inherited_priority,
curthread->base_priority);
/*
* This thread now owns one less priority mutex.
*/
curthread->priority_mutex_count--;
/* Remove the mutex from the threads queue. */
_MUTEX_ASSERT_IS_OWNED(*mutex);
TAILQ_REMOVE(&(*mutex)->m_owner->mutexq,
(*mutex), m_qe);
_MUTEX_INIT_LINK(*mutex);
/*
* Enter a loop to find a waiting thread whose
* active priority will not cause a ceiling
* violation:
*/
while ((((*mutex)->m_owner =
mutex_queue_deq(*mutex)) != NULL) &&
((*mutex)->m_owner->active_priority >
(*mutex)->m_prio)) {
/*
* Either the mutex ceiling priority
* been lowered and/or this threads
* priority has been raised subsequent
* to this thread being queued on the
* waiting list.
*/
tls_set_tcb((*mutex)->m_owner->tcb);
errno = EINVAL;
tls_set_tcb(curthread->tcb);
PTHREAD_NEW_STATE((*mutex)->m_owner,
PS_RUNNING);
/*
* The thread is no longer waiting for
* this mutex:
*/
(*mutex)->m_owner->data.mutex = NULL;
}
/* Check for a new owner: */
if ((*mutex)->m_owner != NULL) {
/*
* Track number of priority mutexes owned:
*/
(*mutex)->m_owner->priority_mutex_count++;
/*
* Add the mutex to the threads list
* of owned mutexes:
*/
TAILQ_INSERT_TAIL(&(*mutex)->m_owner->mutexq,
(*mutex), m_qe);
/*
* The owner is no longer waiting for
* this mutex:
*/
(*mutex)->m_owner->data.mutex = NULL;
/*
* Save the owning threads inherited
* priority:
*/
(*mutex)->m_saved_prio =
(*mutex)->m_owner->inherited_priority;
/*
* The owning thread inherits the
* ceiling priority of the mutex and
* executes at that priority:
*/
(*mutex)->m_owner->inherited_priority =
(*mutex)->m_prio;
(*mutex)->m_owner->active_priority =
(*mutex)->m_prio;
/*
* Make the new owner runnable:
*/
PTHREAD_NEW_STATE((*mutex)->m_owner,
PS_RUNNING);
}
}
break;
/* Trap invalid mutex types: */
default:
/* Return an invalid argument error: */
ret = EINVAL;
break;
}
if ((ret == 0) && (add_reference != 0)) {
/* Increment the reference count: */
(*mutex)->m_refcount++;
}
/* Unlock the mutex structure: */
_SPINUNLOCK(&(*mutex)->lock);
/*
* Undefer and handle pending signals, yielding if
* necessary:
*/
_thread_kern_sig_undefer();
}
/* Return the completion status: */
return (ret);
}
void
funlockfile(FILE * fp)
{
int idx = file_idx(fp);
struct file_lock *p;
/*
* Defer signals to protect the scheduling queues from
* access by the signal handler:
*/
_thread_kern_sig_defer();
/* Lock the hash table: */
_SPINLOCK(&hash_lock);
/*
* Get a pointer to the lock for the file and check that
* the running thread is the one with the lock:
*/
if ((p = find_lock(idx, fp)) != NULL &&
p->owner == _thread_run) {
/*
* Check if this thread has locked the FILE
* more than once:
*/
if (p->count > 1)
/*
* Decrement the count of the number of
* times the running thread has locked this
* file:
*/
p->count--;
else {
/*
* The running thread will release the
* lock now:
*/
p->count = 0;
/* Get the new owner of the lock: */
if ((p->owner = TAILQ_FIRST(&p->l_head)) != NULL) {
/* Pop the thread off the queue: */
TAILQ_REMOVE(&p->l_head,p->owner,qe);
/*
* This is the first lock for the new
* owner:
*/
p->count = 1;
/* Allow the new owner to run: */
PTHREAD_NEW_STATE(p->owner,PS_RUNNING);
}
}
}
/* Unlock the hash table: */
_SPINUNLOCK(&hash_lock);
/*
* Undefer and handle pending signals, yielding if
* necessary:
*/
_thread_kern_sig_undefer();
}
int
_pthread_cond_broadcast(pthread_cond_t * cond)
{
int rval = 0;
pthread_t pthread;
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) {
/*
* Defer signals to protect the scheduling queues
* from access by the signal handler:
*/
_thread_kern_sig_defer();
/* Lock the condition variable structure: */
_SPINLOCK(&(*cond)->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 = cond_queue_deq(*cond)) != NULL) {
/*
* Wake up the signaled thread:
*/
PTHREAD_NEW_STATE(pthread, PS_RUNNING);
}
/* 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: */
_SPINUNLOCK(&(*cond)->lock);
/*
* Undefer and handle pending signals, yielding if
* necessary:
*/
_thread_kern_sig_undefer();
}
/* 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 interrupted = 0;
int seqno;
_thread_enter_cancellation_point();
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);
/*
* 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.
*/
do {
/* Lock the condition variable structure: */
_SPINLOCK(&(*cond)->lock);
/*
* 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;
/* Unlock the condition variable structure: */
_SPINUNLOCK(&(*cond)->lock);
} else {
/* Set the wakeup time: */
curthread->wakeup_time.tv_sec =
abstime->tv_sec;
curthread->wakeup_time.tv_nsec =
abstime->tv_nsec;
/* 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);
/* Remember the mutex and sequence number: */
(*cond)->c_mutex = *mutex;
seqno = (*cond)->c_seqno;
/* Unlock the mutex: */
if ((rval = _mutex_cv_unlock(mutex)) != 0) {
/*
* Cannot unlock the mutex, so remove
* the running thread from the condition
* variable queue:
*/
cond_queue_remove(*cond, curthread);
/* Check for no more waiters: */
if (TAILQ_FIRST(&(*cond)->c_queue) == NULL)
(*cond)->c_mutex = NULL;
/* Unlock the condition variable structure: */
_SPINUNLOCK(&(*cond)->lock);
} else {
/*
* Schedule the next thread and unlock
* the condition variable structure:
*/
_thread_kern_sched_state_unlock(PS_COND_WAIT,
&(*cond)->lock, __FILE__, __LINE__);
done = (seqno != (*cond)->c_seqno);
interrupted = curthread->interrupted;
/*
* Check if the wait was interrupted
* (canceled) or needs to be resumed
* after handling a signal.
*/
if (interrupted != 0) {
/*
* Lock the mutex and ignore any
* errors. Note that even
* though this thread may have
* been canceled, POSIX requires
* that the mutex be reacquired
* prior to cancellation.
*/
(void)_mutex_cv_lock(mutex);
} else {
/*
* Lock the condition variable
* while removing the thread.
*/
_SPINLOCK(&(*cond)->lock);
cond_queue_remove(*cond,
curthread);
/* Check for no more waiters: */
if (TAILQ_FIRST(&(*cond)->c_queue) == NULL)
(*cond)->c_mutex = NULL;
_SPINUNLOCK(&(*cond)->lock);
/* Lock the mutex: */
rval = _mutex_cv_lock(mutex);
/*
* Return ETIMEDOUT if the wait
* timed out and there wasn't an
* error locking the mutex:
*/
if ((curthread->timeout != 0)
&& rval == 0)
rval = ETIMEDOUT;
}
}
}
break;
/* Trap invalid condition variable types: */
default:
/* Unlock the condition variable structure: */
_SPINUNLOCK(&(*cond)->lock);
/* Return an invalid argument error: */
rval = EINVAL;
break;
}
if ((interrupted != 0) && (curthread->continuation != NULL))
curthread->continuation((void *) curthread);
} while ((done == 0) && (rval == 0));
_thread_leave_cancellation_point();
/* Return the completion status: */
return (rval);
}
void
_thread_arc4_unlock()
{
_SPINUNLOCK(&arc4_lock);
}
void
_thread_atexit_unlock()
{
_SPINUNLOCK(&atexit_lock);
}
void
_thread_malloc_unlock()
{
_SPINUNLOCK(&malloc_lock);
}
int
_pthread_mutex_lock(pthread_mutex_t * mutex)
{
struct pthread *curthread = _get_curthread();
int ret = 0;
if (_thread_initial == NULL)
_thread_init();
if (mutex == NULL)
return (EINVAL);
/*
* If the mutex is statically initialized, perform the dynamic
* initialization:
*/
if ((*mutex == NULL) &&
((ret = init_static(mutex)) != 0))
return (ret);
/* Reset the interrupted flag: */
curthread->interrupted = 0;
/*
* Enter a loop waiting to become the mutex owner. We need a
* loop 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.
*/
do {
/*
* Defer signals to protect the scheduling queues from
* access by the signal handler:
*/
_thread_kern_sig_defer();
/* Lock the mutex structure: */
_SPINLOCK(&(*mutex)->lock);
/*
* If the mutex was statically allocated, properly
* initialize the tail queue.
*/
if (((*mutex)->m_flags & MUTEX_FLAGS_INITED) == 0) {
TAILQ_INIT(&(*mutex)->m_queue);
(*mutex)->m_flags |= MUTEX_FLAGS_INITED;
_MUTEX_INIT_LINK(*mutex);
}
/* Process according to mutex type: */
switch ((*mutex)->m_protocol) {
/* Default POSIX mutex: */
case PTHREAD_PRIO_NONE:
if ((*mutex)->m_owner == NULL) {
/* Lock the mutex for this thread: */
(*mutex)->m_owner = curthread;
/* Add to the list of owned mutexes: */
_MUTEX_ASSERT_NOT_OWNED(*mutex);
TAILQ_INSERT_TAIL(&curthread->mutexq,
(*mutex), m_qe);
} else if ((*mutex)->m_owner == curthread)
ret = mutex_self_lock(*mutex);
else {
/*
* Join the queue of threads waiting to lock
* the mutex:
*/
mutex_queue_enq(*mutex, curthread);
/*
* Keep a pointer to the mutex this thread
* is waiting on:
*/
curthread->data.mutex = *mutex;
/*
* Unlock the mutex structure and schedule the
* next thread:
*/
_thread_kern_sched_state_unlock(PS_MUTEX_WAIT,
&(*mutex)->lock, __FILE__, __LINE__);
/* Lock the mutex structure again: */
_SPINLOCK(&(*mutex)->lock);
}
break;
/* POSIX priority inheritence mutex: */
case PTHREAD_PRIO_INHERIT:
/* Check if this mutex is not locked: */
if ((*mutex)->m_owner == NULL) {
/* Lock the mutex for this thread: */
(*mutex)->m_owner = curthread;
/* Track number of priority mutexes owned: */
curthread->priority_mutex_count++;
/*
* The mutex takes on attributes of the
* running thread when there are no waiters.
*/
(*mutex)->m_prio = curthread->active_priority;
(*mutex)->m_saved_prio =
curthread->inherited_priority;
curthread->inherited_priority =
(*mutex)->m_prio;
/* Add to the list of owned mutexes: */
_MUTEX_ASSERT_NOT_OWNED(*mutex);
TAILQ_INSERT_TAIL(&curthread->mutexq,
(*mutex), m_qe);
} else if ((*mutex)->m_owner == curthread)
ret = mutex_self_lock(*mutex);
else {
/*
* Join the queue of threads waiting to lock
* the mutex:
*/
mutex_queue_enq(*mutex, curthread);
/*
* Keep a pointer to the mutex this thread
* is waiting on:
*/
curthread->data.mutex = *mutex;
if (curthread->active_priority >
(*mutex)->m_prio)
/* Adjust priorities: */
mutex_priority_adjust(*mutex);
/*
* Unlock the mutex structure and schedule the
* next thread:
*/
_thread_kern_sched_state_unlock(PS_MUTEX_WAIT,
&(*mutex)->lock, __FILE__, __LINE__);
/* Lock the mutex structure again: */
_SPINLOCK(&(*mutex)->lock);
}
break;
/* POSIX priority protection mutex: */
case PTHREAD_PRIO_PROTECT:
/* Check for a priority ceiling violation: */
if (curthread->active_priority > (*mutex)->m_prio)
ret = EINVAL;
/* Check if this mutex is not locked: */
else if ((*mutex)->m_owner == NULL) {
/*
* Lock the mutex for the running
* thread:
*/
(*mutex)->m_owner = curthread;
/* Track number of priority mutexes owned: */
curthread->priority_mutex_count++;
/*
* The running thread inherits the ceiling
* priority of the mutex and executes at that
* priority:
*/
curthread->active_priority = (*mutex)->m_prio;
(*mutex)->m_saved_prio =
curthread->inherited_priority;
curthread->inherited_priority =
(*mutex)->m_prio;
/* Add to the list of owned mutexes: */
_MUTEX_ASSERT_NOT_OWNED(*mutex);
TAILQ_INSERT_TAIL(&curthread->mutexq,
(*mutex), m_qe);
} else if ((*mutex)->m_owner == curthread)
ret = mutex_self_lock(*mutex);
else {
/*
* Join the queue of threads waiting to lock
* the mutex:
*/
mutex_queue_enq(*mutex, curthread);
/*
* Keep a pointer to the mutex this thread
* is waiting on:
*/
curthread->data.mutex = *mutex;
/* Clear any previous error: */
errno = 0;
/*
* Unlock the mutex structure and schedule the
* next thread:
*/
_thread_kern_sched_state_unlock(PS_MUTEX_WAIT,
&(*mutex)->lock, __FILE__, __LINE__);
/* Lock the mutex structure again: */
_SPINLOCK(&(*mutex)->lock);
/*
* The threads priority may have changed while
* waiting for the mutex causing a ceiling
* violation.
*/
ret = errno;
errno = 0;
}
break;
/* Trap invalid mutex types: */
default:
/* Return an invalid argument error: */
ret = EINVAL;
break;
}
/*
* Check to see if this thread was interrupted and
* is still in the mutex queue of waiting threads:
*/
if (curthread->interrupted != 0)
mutex_queue_remove(*mutex, curthread);
/* Unlock the mutex structure: */
_SPINUNLOCK(&(*mutex)->lock);
/*
* Undefer and handle pending signals, yielding if
* necessary:
*/
_thread_kern_sig_undefer();
} while (((*mutex)->m_owner != curthread) && (ret == 0) &&
(curthread->interrupted == 0));
if (curthread->interrupted != 0 &&
curthread->continuation != NULL)
curthread->continuation((void *) curthread);
/* Return the completion status: */
return (ret);
}
int
_pthread_mutex_trylock(pthread_mutex_t * mutex)
{
struct pthread *curthread = _get_curthread();
int ret = 0;
if (mutex == NULL)
ret = EINVAL;
/*
* If the mutex is statically initialized, perform the dynamic
* initialization:
*/
else if (*mutex != NULL || (ret = init_static(mutex)) == 0) {
/*
* Defer signals to protect the scheduling queues from
* access by the signal handler:
*/
_thread_kern_sig_defer();
/* Lock the mutex structure: */
_SPINLOCK(&(*mutex)->lock);
/*
* If the mutex was statically allocated, properly
* initialize the tail queue.
*/
if (((*mutex)->m_flags & MUTEX_FLAGS_INITED) == 0) {
TAILQ_INIT(&(*mutex)->m_queue);
_MUTEX_INIT_LINK(*mutex);
(*mutex)->m_flags |= MUTEX_FLAGS_INITED;
}
/* Process according to mutex type: */
switch ((*mutex)->m_protocol) {
/* Default POSIX mutex: */
case PTHREAD_PRIO_NONE:
/* Check if this mutex is not locked: */
if ((*mutex)->m_owner == NULL) {
/* Lock the mutex for the running thread: */
(*mutex)->m_owner = curthread;
/* Add to the list of owned mutexes: */
_MUTEX_ASSERT_NOT_OWNED(*mutex);
TAILQ_INSERT_TAIL(&curthread->mutexq,
(*mutex), m_qe);
} else if ((*mutex)->m_owner == curthread)
ret = mutex_self_trylock(*mutex);
else
/* Return a busy error: */
ret = EBUSY;
break;
/* POSIX priority inheritence mutex: */
case PTHREAD_PRIO_INHERIT:
/* Check if this mutex is not locked: */
if ((*mutex)->m_owner == NULL) {
/* Lock the mutex for the running thread: */
(*mutex)->m_owner = curthread;
/* Track number of priority mutexes owned: */
curthread->priority_mutex_count++;
/*
* The mutex takes on the attributes of the
* running thread when there are no waiters.
*/
(*mutex)->m_prio = curthread->active_priority;
(*mutex)->m_saved_prio =
curthread->inherited_priority;
/* Add to the list of owned mutexes: */
_MUTEX_ASSERT_NOT_OWNED(*mutex);
TAILQ_INSERT_TAIL(&curthread->mutexq,
(*mutex), m_qe);
} else if ((*mutex)->m_owner == curthread)
ret = mutex_self_trylock(*mutex);
else
/* Return a busy error: */
ret = EBUSY;
break;
/* POSIX priority protection mutex: */
case PTHREAD_PRIO_PROTECT:
/* Check for a priority ceiling violation: */
if (curthread->active_priority > (*mutex)->m_prio)
ret = EINVAL;
/* Check if this mutex is not locked: */
else if ((*mutex)->m_owner == NULL) {
/* Lock the mutex for the running thread: */
(*mutex)->m_owner = curthread;
/* Track number of priority mutexes owned: */
curthread->priority_mutex_count++;
/*
* The running thread inherits the ceiling
* priority of the mutex and executes at that
* priority.
*/
curthread->active_priority = (*mutex)->m_prio;
(*mutex)->m_saved_prio =
curthread->inherited_priority;
curthread->inherited_priority =
(*mutex)->m_prio;
/* Add to the list of owned mutexes: */
_MUTEX_ASSERT_NOT_OWNED(*mutex);
TAILQ_INSERT_TAIL(&curthread->mutexq,
(*mutex), m_qe);
} else if ((*mutex)->m_owner == curthread)
ret = mutex_self_trylock(*mutex);
else
/* Return a busy error: */
ret = EBUSY;
break;
/* Trap invalid mutex types: */
default:
/* Return an invalid argument error: */
ret = EINVAL;
break;
}
/* Unlock the mutex structure: */
_SPINUNLOCK(&(*mutex)->lock);
/*
* Undefer and handle pending signals, yielding if
* necessary:
*/
_thread_kern_sig_undefer();
}
/* Return the completion status: */
return (ret);
}