1 files changed, 105 insertions, 0 deletions
diff --git a/cpukit/posix/src/prwlocktimedrdlock.c b/cpukit/posix/src/prwlocktimedrdlock.c
new file mode 100644
index 0000000000..d6df7815a8
--- /dev/null
+++ b/cpukit/posix/src/prwlocktimedrdlock.c
@@ -0,0 +1,105 @@
+/*
+ *  POSIX RWLock Manager -- Attempt to Obtain a Read Lock on a RWLock Instance
+ *
+ *  COPYRIGHT (c) 1989-2008.
+ *  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>
+#include <rtems/posix/time.h>
+
+/*
+ *  pthread_rwlock_timedrdlock
+ *
+ *  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_timedrdlock(
+  pthread_rwlock_t      *rwlock,
+  const struct timespec *abstime
+)
+{
+  POSIX_RWLock_Control                        *the_rwlock;
+  Objects_Locations                            location;
+  Watchdog_Interval                            ticks;
+  bool                                         do_wait = true;
+  POSIX_Absolute_timeout_conversion_results_t  status;
+
+  if ( !rwlock )
+    return EINVAL;
+
+  /*
+   *  POSIX requires that blocking calls with timeouts that take
+   *  an absolute timeout must ignore issues with the absolute
+   *  time provided if the operation would otherwise succeed.
+   *  So we check the abstime provided, and hold on to whether it
+   *  is valid or not.  If it isn't correct and in the future,
+   *  then we do a polling operation and convert the UNSATISFIED
+   *  status into the appropriate error.
+   *
+   *  If the status is POSIX_ABSOLUTE_TIMEOUT_INVALID,
+   *  POSIX_ABSOLUTE_TIMEOUT_IS_IN_PAST, or POSIX_ABSOLUTE_TIMEOUT_IS_NOW,
+   *  then we should not wait.
+   */
+  status = _POSIX_Absolute_timeout_to_ticks( abstime, &ticks );
+  if ( status != POSIX_ABSOLUTE_TIMEOUT_IS_IN_FUTURE )
+    do_wait = false;
+
+  the_rwlock = _POSIX_RWLock_Get( rwlock, &location );
+  switch ( location ) {
+
+    case OBJECTS_LOCAL:
+
+      _CORE_RWLock_Obtain_for_reading(
+	&the_rwlock->RWLock,
+	*rwlock,
+	do_wait,
+	ticks,
+	NULL
+      );
+
+      _Thread_Enable_dispatch();
+      if ( !do_wait ) {
+        if ( _Thread_Executing->Wait.return_code == CORE_RWLOCK_UNAVAILABLE ) {
+	  if ( status == POSIX_ABSOLUTE_TIMEOUT_INVALID )
+	    return EINVAL;
+	  if ( status == POSIX_ABSOLUTE_TIMEOUT_IS_IN_PAST ||
+	       status == POSIX_ABSOLUTE_TIMEOUT_IS_NOW )
+	    return ETIMEDOUT;
+        }
+      }
+
+      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;
+}