2008-07-18 Joel Sherrill <joel.sherrill@oarcorp.com>

	PR 1291/cpukit
	* itron/inline/rtems/itron/semaphore.inl, itron/src/twai_sem.c,
	posix/include/mqueue.h, posix/include/rtems/posix/mqueue.h,
	posix/include/rtems/posix/semaphore.h,
	posix/include/rtems/posix/time.h, posix/src/condtimedwait.c,
	posix/src/mqueuereceive.c, posix/src/mqueuerecvsupp.c,
	posix/src/mqueuesend.c, posix/src/mqueuesendsupp.c,
	posix/src/mqueuetimedreceive.c, posix/src/mqueuetimedsend.c,
	posix/src/mutextimedlock.c, posix/src/mutextranslatereturncode.c,
	posix/src/posixtimespecabsolutetimeout.c,
	posix/src/prwlocktimedrdlock.c, posix/src/prwlocktimedwrlock.c,
	posix/src/semaphoretranslatereturncode.c,
	posix/src/semaphorewaitsupp.c, posix/src/semtimedwait.c,
	posix/src/semtrywait.c, posix/src/semwait.c,
	posix/src/sigtimedwait.c, posix/src/timersettime.c,
	posix/src/ualarm.c, rtems/src/semobtain.c,
	rtems/src/semtranslatereturncode.c,
	score/include/rtems/score/coremutex.h,
	score/include/rtems/score/coresem.h, score/src/coresemseize.c: This
	patch addresses issues on implementation of the timeout on the
	following POSIX services. Some of these services incorrectly took a
	timeout as a relative time. Others would compute a 0 delta to timeout
	if the absolute time and the current time were equal and thus
	incorrectly block the caller forever. The root of the confusion is
	that POSIX specifies that if the timeout is incorrect (e.g. in the
	past, is now, or is numerically invalid), that it does not matter if
	the call would succeed without blocking. This is in contrast to RTEMS
	programming style where all errors are checked before any critical
	sections are entered. This fix implemented a more uniform way of
	handling POSIX absolute time timeouts.
	    + pthread_cond_timedwait - could block forever
	    + mq_timedreceive - used relative not absolute time
	    + mq_timedsend - used relative not absolute time
	    + pthread_mutex_timedlock - used relative not absolute time
	    + pthread_rwlock_timedrdlock- used relative not absolute time
	    + pthread_rwlock_timedwrlock- used relative not absolute time
	    + sem_timedwait - could block forever

1 files changed, 16 insertions, 4 deletions

diff --git a/cpukit/posix/src/mqueuerecvsupp.c b/cpukit/posix/src/mqueuerecvsupp.c
index d42f632889..08d7fbc0a5 100644
--- a/cpukit/posix/src/mqueuerecvsupp.c
+++ b/cpukit/posix/src/mqueuerecvsupp.c
@@ -11,7 +11,7 @@
  *         This code ignores the O_RDONLY/O_WRONLY/O_RDWR flag at open
  *         time.
  *
- *  COPYRIGHT (c) 1989-2007.
+ *  COPYRIGHT (c) 1989-2008.
  *  On-Line Applications Research Corporation (OAR).
  *
  *  The license and distribution terms for this file may be
@@ -39,8 +39,7 @@
 #include <rtems/posix/mqueue.h>
 #include <rtems/posix/time.h>
 
-/*PAGE
- *
+/*
  *  _POSIX_Message_queue_Receive_support
  *
  *  NOTE: XXX Document how size, priority, length, and the buffer go
@@ -52,6 +51,7 @@ ssize_t _POSIX_Message_queue_Receive_support(
   char               *msg_ptr,
   size_t              msg_len,
   unsigned int       *msg_prio,
+  boolean             wait,
   Watchdog_Interval   timeout
 )
 {
@@ -59,6 +59,7 @@ ssize_t _POSIX_Message_queue_Receive_support(
   POSIX_Message_queue_Control_fd  *the_mq_fd;
   Objects_Locations                location;
   size_t                           length_out;
+  boolean                          do_wait;
 
   the_mq_fd = _POSIX_Message_queue_Get_fd( mqdes, &location );
   switch ( location ) {
@@ -83,12 +84,23 @@ ssize_t _POSIX_Message_queue_Receive_support(
 
       length_out = -1;
 
+      /*
+       *  A timed receive with a bad time will do a poll regardless.
+       */
+      if ( wait )
+        do_wait = (the_mq_fd->oflag & O_NONBLOCK) ? FALSE : TRUE;
+      else
+        do_wait = wait;
+
+      /*
+       *  Now perform the actual message receive
+       */
       _CORE_message_queue_Seize(
         &the_mq->Message_queue,
         mqdes,
         msg_ptr,
         &length_out,
-        (the_mq_fd->oflag & O_NONBLOCK) ? FALSE : TRUE,
+        do_wait,
         timeout
       );