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-rw-r--r--pthreads/pthread_rwlock_trywrlock.c245
1 files changed, 122 insertions, 123 deletions
diff --git a/pthreads/pthread_rwlock_trywrlock.c b/pthreads/pthread_rwlock_trywrlock.c
index 8ba8b5dad..3c6fccaa1 100644
--- a/pthreads/pthread_rwlock_trywrlock.c
+++ b/pthreads/pthread_rwlock_trywrlock.c
@@ -1,123 +1,122 @@
-/*
- * pthread_rwlock_trywrlock.c
- *
- * Description:
- * This translation unit implements read/write lock primitives.
- *
- * --------------------------------------------------------------------------
- *
- * 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 <errno.h>
-#include <limits.h>
-
-#include "pthread.h"
-#include "implement.h"
-
-int
-pthread_rwlock_trywrlock (pthread_rwlock_t * rwlock)
-{
- int result, result1;
- pthread_rwlock_t rwl;
-
- if (rwlock == NULL || *rwlock == NULL)
- {
- return EINVAL;
- }
-
- /*
- * We do a quick check to see if we need to do more work
- * to initialise a static rwlock. We check
- * again inside the guarded section of ptw32_rwlock_check_need_init()
- * to avoid race conditions.
- */
- if (*rwlock == PTHREAD_RWLOCK_INITIALIZER)
- {
- result = ptw32_rwlock_check_need_init (rwlock);
-
- if (result != 0 && result != EBUSY)
- {
- return result;
- }
- }
-
- rwl = *rwlock;
-
- if (rwl->nMagic != PTW32_RWLOCK_MAGIC)
- {
- return EINVAL;
- }
-
- if ((result = pthread_mutex_trylock (&(rwl->mtxExclusiveAccess))) != 0)
- {
- return result;
- }
-
- if ((result =
- pthread_mutex_trylock (&(rwl->mtxSharedAccessCompleted))) != 0)
- {
- result1 = pthread_mutex_unlock (&(rwl->mtxExclusiveAccess));
- return ((result1 != 0) ? result1 : result);
- }
-
- if (rwl->nExclusiveAccessCount == 0)
- {
- if (rwl->nCompletedSharedAccessCount > 0)
- {
- rwl->nSharedAccessCount -= rwl->nCompletedSharedAccessCount;
- rwl->nCompletedSharedAccessCount = 0;
- }
-
- if (rwl->nSharedAccessCount > 0)
- {
- if ((result =
- pthread_mutex_unlock (&(rwl->mtxSharedAccessCompleted))) != 0)
- {
- (void) pthread_mutex_unlock (&(rwl->mtxExclusiveAccess));
- return result;
- }
-
- if ((result =
- pthread_mutex_unlock (&(rwl->mtxExclusiveAccess))) == 0)
- {
- result = EBUSY;
- }
- }
- else
- {
- rwl->nExclusiveAccessCount = 1;
- }
- }
- else
- {
- result = EBUSY;
- }
-
- return result;
-}
+/*
+ * pthread_rwlock_trywrlock.c
+ *
+ * Description:
+ * This translation unit implements read/write lock primitives.
+ *
+ * --------------------------------------------------------------------------
+ *
+ * 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 <limits.h>
+
+#include "pthread.h"
+#include "implement.h"
+
+int
+pthread_rwlock_trywrlock (pthread_rwlock_t * rwlock)
+{
+ int result, result1;
+ pthread_rwlock_t rwl;
+
+ if (rwlock == NULL || *rwlock == NULL)
+ {
+ return EINVAL;
+ }
+
+ /*
+ * We do a quick check to see if we need to do more work
+ * to initialise a static rwlock. We check
+ * again inside the guarded section of ptw32_rwlock_check_need_init()
+ * to avoid race conditions.
+ */
+ if (*rwlock == PTHREAD_RWLOCK_INITIALIZER)
+ {
+ result = ptw32_rwlock_check_need_init (rwlock);
+
+ if (result != 0 && result != EBUSY)
+ {
+ return result;
+ }
+ }
+
+ rwl = *rwlock;
+
+ if (rwl->nMagic != PTW32_RWLOCK_MAGIC)
+ {
+ return EINVAL;
+ }
+
+ if ((result = pthread_mutex_trylock (&(rwl->mtxExclusiveAccess))) != 0)
+ {
+ return result;
+ }
+
+ if ((result =
+ pthread_mutex_trylock (&(rwl->mtxSharedAccessCompleted))) != 0)
+ {
+ result1 = pthread_mutex_unlock (&(rwl->mtxExclusiveAccess));
+ return ((result1 != 0) ? result1 : result);
+ }
+
+ if (rwl->nExclusiveAccessCount == 0)
+ {
+ if (rwl->nCompletedSharedAccessCount > 0)
+ {
+ rwl->nSharedAccessCount -= rwl->nCompletedSharedAccessCount;
+ rwl->nCompletedSharedAccessCount = 0;
+ }
+
+ if (rwl->nSharedAccessCount > 0)
+ {
+ if ((result =
+ pthread_mutex_unlock (&(rwl->mtxSharedAccessCompleted))) != 0)
+ {
+ (void) pthread_mutex_unlock (&(rwl->mtxExclusiveAccess));
+ return result;
+ }
+
+ if ((result =
+ pthread_mutex_unlock (&(rwl->mtxExclusiveAccess))) == 0)
+ {
+ result = EBUSY;
+ }
+ }
+ else
+ {
+ rwl->nExclusiveAccessCount = 1;
+ }
+ }
+ else
+ {
+ result = EBUSY;
+ }
+
+ return result;
+}
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