diff options
author | rpj <rpj> | 2005-04-25 01:21:20 +0000 |
---|---|---|
committer | rpj <rpj> | 2005-04-25 01:21:20 +0000 |
commit | 8a78e259203a6edabe53d78b8aa44666e50366e1 (patch) | |
tree | 465e02729ed9a64717d581e0327ce20acf258af8 /sem_wait.c | |
parent | 2baa511d22be44701a1cc2f5c3d6e6d643cbc6be (diff) |
Fix NEED_SEM code (WinCE)
Diffstat (limited to 'sem_wait.c')
-rw-r--r-- | sem_wait.c | 316 |
1 files changed, 162 insertions, 154 deletions
@@ -1,154 +1,162 @@ -/* - * ------------------------------------------------------------- - * - * Module: sem_wait.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" - - -static void PTW32_CDECL -ptw32_sem_wait_cleanup(void * sem) -{ - sem_t s = (sem_t) sem; - - if (pthread_mutex_lock (&s->lock) == 0) - { - ++s->value; - /* Don't release the W32 sema, it should always == 0. */ - (void) pthread_mutex_unlock (&s->lock); - } -} - -int -sem_wait (sem_t * sem) - /* - * ------------------------------------------------------ - * DOCPUBLIC - * This function waits on a semaphore. - * - * PARAMETERS - * sem - * pointer to an instance of sem_t - * - * DESCRIPTION - * This function waits on a 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 or until interrupted by - * a signal. - * - * 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. - * - * ------------------------------------------------------ - */ -{ - int result = 0; - sem_t s = *sem; - - if (s == NULL) - { - result = EINVAL; - } - else - { - -#ifdef NEED_SEM - - result = pthreadCancelableWait (s->event); - -#else /* NEED_SEM */ - - /* - * sem_wait is a cancelation point and it's easy to test before - * modifying the sem value - */ - pthread_testcancel(); - - if ((result = pthread_mutex_lock (&s->lock)) == 0) - { - int v = --s->value; - - (void) pthread_mutex_unlock (&s->lock); - - if (v < 0) - { - /* Must wait */ -#ifdef _MSC_VER -#pragma inline_depth(0) -#endif - pthread_cleanup_push(ptw32_sem_wait_cleanup, (void *) s); - result = pthreadCancelableWait (s->sem); - pthread_cleanup_pop(result != 0); -#ifdef _MSC_VER -#pragma inline_depth() -#endif - } - } - -#endif /* NEED_SEM */ - - } - - if (result != 0) - { - errno = result; - return -1; - } - -#ifdef NEED_SEM - - ptw32_decrease_semaphore (sem); - -#endif /* NEED_SEM */ - - return 0; - -} /* sem_wait */ +/*
+ * -------------------------------------------------------------
+ *
+ * Module: sem_wait.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"
+
+
+static void PTW32_CDECL
+ptw32_sem_wait_cleanup(void * sem)
+{
+ sem_t s = (sem_t) sem;
+
+ if (pthread_mutex_lock (&s->lock) == 0)
+ {
+ ++s->value;
+#ifdef NEED_SEM
+
+ if (s->value > 0)
+ {
+ s->leftToUnblock = 0;
+ }
+#else
+ /*
+ * Don't release the W32 sema, it doesn't need adjustment
+ * because it doesn't record the number of waiters.
+ */
+#endif /* NEED_SEM */
+ (void) pthread_mutex_unlock (&s->lock);
+ }
+}
+
+int
+sem_wait (sem_t * sem)
+ /*
+ * ------------------------------------------------------
+ * DOCPUBLIC
+ * This function waits on a semaphore.
+ *
+ * PARAMETERS
+ * sem
+ * pointer to an instance of sem_t
+ *
+ * DESCRIPTION
+ * This function waits on a 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 or until interrupted by
+ * a signal.
+ *
+ * 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.
+ *
+ * ------------------------------------------------------
+ */
+{
+ int result = 0;
+ sem_t s = *sem;
+
+ if (s == NULL)
+ {
+ result = EINVAL;
+ }
+ else
+ {
+
+ /* Faster to test before adjusting the count */
+ pthread_testcancel();
+
+ if ((result = pthread_mutex_lock (&s->lock)) == 0)
+ {
+ int v = --s->value;
+
+ (void) pthread_mutex_unlock (&s->lock);
+
+ if (v < 0)
+ {
+#ifdef _MSC_VER
+#pragma inline_depth(0)
+#endif
+ /* Must wait */
+ pthread_cleanup_push(ptw32_sem_wait_cleanup, (void *) s);
+ result = pthreadCancelableWait (s->sem);
+ pthread_cleanup_pop(result);
+#ifdef _MSC_VER
+#pragma inline_depth()
+#endif
+ }
+#ifdef NEED_SEM
+
+ if (!result && pthread_mutex_lock (&s->lock) == 0)
+ {
+ if (s->leftToUnblock > 0)
+ {
+ --s->leftToUnblock;
+ SetEvent(s->sem);
+ }
+ (void) pthread_mutex_unlock (&s->lock);
+ }
+
+#endif /* NEED_SEM */
+
+ }
+
+ }
+
+ if (result != 0)
+ {
+ errno = result;
+ return -1;
+ }
+
+ return 0;
+
+} /* sem_wait */
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