diff options
Diffstat (limited to 'libs/pthreads/src/ptw32_semwait.c')
| -rw-r--r-- | libs/pthreads/src/ptw32_semwait.c | 161 |
1 files changed, 69 insertions, 92 deletions
diff --git a/libs/pthreads/src/ptw32_semwait.c b/libs/pthreads/src/ptw32_semwait.c index c3c4fd0e5e..3c2ab535bb 100644 --- a/libs/pthreads/src/ptw32_semwait.c +++ b/libs/pthreads/src/ptw32_semwait.c @@ -6,34 +6,38 @@ * * -------------------------------------------------------------------------- * - * Pthreads-win32 - POSIX Threads Library for Win32 + * Pthreads4w - POSIX Threads Library for Win32 * Copyright(C) 1998 John E. Bossom - * Copyright(C) 1999,2005 Pthreads-win32 contributors - * - * Contact Email: rpj@callisto.canberra.edu.au - * + * Copyright(C) 1999-2018, Pthreads4w contributors + * + * Homepage: https://sourceforge.net/projects/pthreads4w/ + * * The current list of contributors is contained * in the file CONTRIBUTORS included with the source * code distribution. The list can also be seen at the * following World Wide Web location: - * http://sources.redhat.com/pthreads-win32/contributors.html - * - * This library is free software; you can redistribute it and/or - * modify it under the terms of the GNU Lesser General Public - * License as published by the Free Software Foundation; either - * version 2 of the License, or (at your option) any later version. - * - * This library is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - * Lesser General Public License for more details. - * - * You should have received a copy of the GNU Lesser General Public - * License along with this library in the file COPYING.LIB; - * if not, write to the Free Software Foundation, Inc., - * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA + * https://sourceforge.net/p/pthreads4w/wiki/Contributors/ + * + * This file is part of Pthreads4w. + * + * Pthreads4w is free software: you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation, either version 3 of the License, or + * (at your option) any later version. + * + * Pthreads4w is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with Pthreads4w. If not, see <http://www.gnu.org/licenses/>. * */ +#ifdef HAVE_CONFIG_H +# include <config.h> +#endif + #if !defined(_UWIN) /*# include <process.h> */ #endif @@ -43,90 +47,63 @@ int ptw32_semwait (sem_t * sem) - /* - * ------------------------------------------------------ - * DESCRIPTION - * This function waits on a POSIX semaphore. If the - * semaphore value is greater than zero, it decreases - * its value by one. If the semaphore value is zero, then - * the calling thread (or process) is blocked until it can - * successfully decrease the value. - * - * Unlike sem_wait(), this routine is non-cancelable. - * - * RESULTS - * 0 successfully decreased semaphore, - * -1 failed, error in errno. - * ERRNO - * EINVAL 'sem' is not a valid semaphore, - * ENOSYS semaphores are not supported, - * EINTR the function was interrupted by a signal, - * EDEADLK a deadlock condition was detected. - * - * ------------------------------------------------------ - */ +/* + * ------------------------------------------------------ + * DESCRIPTION + * This function waits on a POSIX semaphore. If the + * semaphore value is greater than zero, it decreases + * its value by one. If the semaphore value is zero, then + * the calling thread (or process) is blocked until it can + * successfully decrease the value. + * + * Unlike sem_wait(), this routine is non-cancelable. + * + * RESULTS + * 0 successfully decreased semaphore, + * -1 failed, error in errno. + * ERRNO + * EINVAL 'sem' is not a valid semaphore, + * ENOSYS semaphores are not supported, + * EINTR the function was interrupted by a signal, + * EDEADLK a deadlock condition was detected. + * + * ------------------------------------------------------ + */ { + ptw32_mcs_local_node_t node; + int v; int result = 0; sem_t s = *sem; - if (s == NULL) - { - result = EINVAL; - } - else + ptw32_mcs_lock_acquire(&s->lock, &node); + v = --s->value; + ptw32_mcs_lock_release(&node); + + if (v < 0) { - if ((result = pthread_mutex_lock (&s->lock)) == 0) + /* Must wait */ + if (WaitForSingleObject (s->sem, INFINITE) == WAIT_OBJECT_0) { - int v; - - /* See sem_destroy.c - */ - if (*sem == NULL) - { - (void) pthread_mutex_unlock (&s->lock); - errno = EINVAL; - return -1; - } - - v = --s->value; - (void) pthread_mutex_unlock (&s->lock); - - if (v < 0) - { - /* Must wait */ - if (WaitForSingleObject (s->sem, INFINITE) == WAIT_OBJECT_0) - { #if defined(NEED_SEM) - if (pthread_mutex_lock (&s->lock) == 0) - { - if (*sem == NULL) - { - (void) pthread_mutex_unlock (&s->lock); - errno = EINVAL; - return -1; - } - - if (s->leftToUnblock > 0) - { - --s->leftToUnblock; - SetEvent(s->sem); - } - (void) pthread_mutex_unlock (&s->lock); - } -#endif - return 0; - } + ptw32_mcs_lock_acquire(&s->lock, &node); + if (s->leftToUnblock > 0) + { + --s->leftToUnblock; + SetEvent(s->sem); } - else - { - return 0; - } + ptw32_mcs_lock_release(&node); +#endif +return 0; } } + else + { + return 0; + } if (result != 0) { - errno = result; + PTW32_SET_ERRNO(result); return -1; } |