1 files changed, 74 insertions, 0 deletions
diff --git a/cpukit/posix/src/prwlocktryrdlock.c b/cpukit/posix/src/prwlocktryrdlock.c
new file mode 100644
index 0000000000..f07edf5f4d
--- /dev/null
+++ b/cpukit/posix/src/prwlocktryrdlock.c
@@ -0,0 +1,74 @@
+/*
+ *  POSIX RWLock Manager -- Attempt to Obtain a Read Lock on a RWLock Instance
+ *
+ *  COPYRIGHT (c) 1989-2007.
+ *  On-Line Applications Research Corporation (OAR).
+ *
+ *  The license and distribution terms for this file may be
+ *  found in the file LICENSE in this distribution or at
+ *  http://www.rtems.com/license/LICENSE.
+ *
+ *  $Id$
+ */
+
+#if HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <pthread.h>
+#include <errno.h>
+
+#include <rtems/system.h>
+#include <rtems/posix/rwlock.h>
+
+/*
+ *  pthread_rwlock_tryrdlock
+ *
+ *  This directive attempts to obtain a read only lock on an rwlock instance.
+ *
+ *  Input parameters:
+ *    rwlock          - pointer to rwlock id
+ *
+ *  Output parameters:
+ *    0          - if successful
+ *    error code - if unsuccessful
+ */
+
+int pthread_rwlock_tryrdlock(
+  pthread_rwlock_t  *rwlock
+)
+{
+  POSIX_RWLock_Control  *the_rwlock;
+  Objects_Locations      location;
+
+  if ( !rwlock )
+    return EINVAL;
+
+  the_rwlock = _POSIX_RWLock_Get( rwlock, &location );
+  switch ( location ) {
+
+    case OBJECTS_LOCAL:
+
+      _CORE_RWLock_Obtain_for_reading(
+	&the_rwlock->RWLock,
+	*rwlock,
+	false,                  /* do not wait for the rwlock */
+	0,
+	NULL
+      );
+
+
+      _Thread_Enable_dispatch();
+      return _POSIX_RWLock_Translate_core_RWLock_return_code(
+        (CORE_RWLock_Status) _Thread_Executing->Wait.return_code
+      );
+
+#if defined(RTEMS_MULTIPROCESSING)
+    case OBJECTS_REMOTE:
+#endif
+    case OBJECTS_ERROR:
+      break;
+  }
+
+  return EINVAL;
+}