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authorrpj <rpj>2005-04-25 00:48:05 +0000
committerrpj <rpj>2005-04-25 00:48:05 +0000
commitc2c2749315183f102d8967f37a43394fd39c5abd (patch)
treef56b6fe441eb07ca9de08ea6cc120a45437da5f6 /sem_trywait.c
parent150a7a6e99d3cf8fd0b6315e7b184b5cce0f4ce4 (diff)
Fix NEED_SEM code (WinCE)
Diffstat (limited to 'sem_trywait.c')
-rw-r--r--sem_trywait.c226
1 files changed, 108 insertions, 118 deletions
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 <stdio.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.
- *
- * ------------------------------------------------------
- */
-{
-#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 */