From c2c2749315183f102d8967f37a43394fd39c5abd Mon Sep 17 00:00:00 2001 From: rpj Date: Mon, 25 Apr 2005 00:48:05 +0000 Subject: Fix NEED_SEM code (WinCE) --- sem_trywait.c | 226 ++++++++++++++++++++++++++++------------------------------ 1 file changed, 108 insertions(+), 118 deletions(-) (limited to 'sem_trywait.c') diff --git a/sem_trywait.c b/sem_trywait.c index 640d190..2116222 100644 --- a/sem_trywait.c +++ b/sem_trywait.c @@ -1,118 +1,108 @@ -/* - * ------------------------------------------------------------- - * - * Module: sem_trywait.c - * - * Purpose: - * Semaphores aren't actually part of the PThreads standard. - * They are defined by the POSIX Standard: - * - * POSIX 1003.1b-1993 (POSIX.1b) - * - * ------------------------------------------------------------- - * - * -------------------------------------------------------------------------- - * - * Pthreads-win32 - 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 - * - * 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 - */ - -#include "pthread.h" -#include "semaphore.h" -#include "implement.h" - -#include - -int -sem_trywait (sem_t * sem) - /* - * ------------------------------------------------------ - * DOCPUBLIC - * This function tries to wait on a semaphore. - * - * PARAMETERS - * sem - * pointer to an instance of sem_t - * - * DESCRIPTION - * This function tries to wait on a semaphore. If the - * semaphore value is greater than zero, it decreases - * its value by one. If the semaphore value is zero, then - * this function returns immediately with the error EAGAIN - * - * RESULTS - * 0 successfully decreased semaphore, - * -1 failed, error in errno - * ERRNO - * EAGAIN the semaphore was already locked, - * EINVAL 'sem' is not a valid semaphore, - * ENOTSUP sem_trywait is not supported, - * EINTR the function was interrupted by a signal, - * EDEADLK a deadlock condition was detected. - * - * ------------------------------------------------------ - */ -{ -#ifdef NEED_SEM - - /* - * not yet implemented! - */ - errno = ENOTSUP; - return -1; - -#else /* NEED_SEM */ - - int result = 0; - sem_t s = *sem; - - if (s == NULL) - { - result = EINVAL; - } - else if ((result = pthread_mutex_lock (&s->lock)) == 0) - { - if (--s->value < 0) - { - s->value++; - result = EAGAIN; - } - - (void) pthread_mutex_unlock (&s->lock); - } - - if (result != 0) - { - errno = result; - return -1; - } - - return 0; - -#endif /* NEED_SEM */ - -} /* sem_trywait */ +/* + * ------------------------------------------------------------- + * + * Module: sem_trywait.c + * + * Purpose: + * Semaphores aren't actually part of the PThreads standard. + * They are defined by the POSIX Standard: + * + * POSIX 1003.1b-1993 (POSIX.1b) + * + * ------------------------------------------------------------- + * + * -------------------------------------------------------------------------- + * + * Pthreads-win32 - 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 + * + * 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 + */ + +#include "pthread.h" +#include "semaphore.h" +#include "implement.h" + + +int +sem_trywait (sem_t * sem) + /* + * ------------------------------------------------------ + * DOCPUBLIC + * This function tries to wait on a semaphore. + * + * PARAMETERS + * sem + * pointer to an instance of sem_t + * + * DESCRIPTION + * This function tries to wait on a semaphore. If the + * semaphore value is greater than zero, it decreases + * its value by one. If the semaphore value is zero, then + * this function returns immediately with the error EAGAIN + * + * RESULTS + * 0 successfully decreased semaphore, + * -1 failed, error in errno + * ERRNO + * EAGAIN the semaphore was already locked, + * EINVAL 'sem' is not a valid semaphore, + * ENOTSUP sem_trywait is not supported, + * EINTR the function was interrupted by a signal, + * EDEADLK a deadlock condition was detected. + * + * ------------------------------------------------------ + */ +{ + int result = 0; + sem_t s = *sem; + + if (s == NULL) + { + result = EINVAL; + } + else if ((result = pthread_mutex_lock (&s->lock)) == 0) + { + if (s->value > 0) + { + s->value--; + } + else + { + result = EAGAIN; + } + + (void) pthread_mutex_unlock (&s->lock); + } + + if (result != 0) + { + errno = result; + return -1; + } + + return 0; + +} /* sem_trywait */ -- cgit v1.2.3