Ticket #841: timedwait.diffs

Index: semtimedwait.c
===================================================================
RCS file: /usr1/CVS/rtems/cpukit/posix/src/semtimedwait.c,v
retrieving revision 1.4
diff -u -r1.4 semtimedwait.c
--- semtimedwait.c      1 Sep 2005 14:44:04 -0000       1.4
+++ semtimedwait.c      2 Nov 2005 19:28:35 -0000
@@ -40,24 +40,30 @@
   struct timespec   difference;
 
   /*
-   *  Error check the absolute time to timeout
+   * POSIX says:
+   * "Under no circumstance shall the function fail with a timeout if the
+   * semaphore can be locked immediately."  It also mentions it doesn't even
+   * need to be checked.
+   */
+  if (sem_trywait(sem) == 0)
+    return 0;
+
+  /*
+   *  Error check the absolute time to timeout.
    */
-  if ( /* abstime->tv_sec < 0 || */ abstime->tv_nsec ) /* tv_sec is unsigned */
-    return EINVAL;
 
   if ( abstime->tv_nsec >= TOD_NANOSECONDS_PER_SECOND )
-    return EINVAL;
+      rtems_set_errno_and_return_minus_one( EINVAL );
   
   (void) clock_gettime( CLOCK_REALTIME, &current_time );
 
   /*
    *  Make sure the abstime is in the future
    */
-  if ( abstime->tv_sec < current_time.tv_sec )
-    return EINVAL;
-  if ( (abstime->tv_sec == current_time.tv_sec) &&
-       (abstime->tv_nsec <= current_time.tv_nsec) )
-    return EINVAL;
+  if ( abstime->tv_sec < current_time.tv_sec ||
+  ((abstime->tv_sec == current_time.tv_sec) &&
+   (abstime->tv_nsec <= current_time.tv_nsec)) )
+      rtems_set_errno_and_return_minus_one( ETIMEDOUT );
 
   _POSIX_Timespec_subtract( &current_time, abstime, &difference );