rtems: Constify rtems_task_wake_when()

Add a parameter to _TOD_Validate() to disable the validation of the
ticks member.

There are two reasons for this change.  Firstly, in
rtems_task_wake_when() was a double check for time_buffer == NULL (one
in rtems_task_wake_when() and one in _TOD_Validate()).  Secondly, the
ticks member is ignored by rtems_task_wake_when().  This was done with a
write of zero to the ticks member and thus a modification of the
user-provided structure.  Now the structure is no longer modified.
Using a mask parameter is quite efficient. You just have to load an
immediate value and there are no additional branches in _TOD_Validate().

Close #4406.

6 files changed, 28 insertions, 16 deletions

diff --git a/cpukit/include/rtems/rtems/clockimpl.h b/cpukit/include/rtems/rtems/clockimpl.h
index 8ec4f0f6e3..404b8234ee 100644
--- a/cpukit/include/rtems/rtems/clockimpl.h
+++ b/cpukit/include/rtems/rtems/clockimpl.h
@@ -35,19 +35,34 @@ extern "C" {
  */
 
 /**
- * @brief TOD Validate
+ * @brief Using this constant for the ticks mask disables the validation of the
+ *   ticks member in _TOD_Validate().
+ */
+#define TOD_DISABLE_TICKS_VALIDATION 0
+
+/**
+ * @brief Using this constant for the ticks mask enables the validation of the
+ *   ticks member in _TOD_Validate().
+ */
+#define TOD_ENABLE_TICKS_VALIDATION UINT32_MAX
+
+/**
+ * @brief Validates the time of day.
  *
- * This support function tests whether @a the_tod references
- * a valid time of day.
+ * @param the_tod is the reference to the time of day structure to validate or
+ *   NULL.
  *
- * @param the_tod A reference to the time of day structure to validate.
+ * @param ticks_mask is the mask for the ticks member of the time of day.  Use
+ *   #TOD_ENABLE_TICKS_VALIDATION to validate the ticks member.  Use
+ *   #TOD_DISABLE_TICKS_VALIDATION to skip the validation of the ticks member.
  *
  * @retval RTEMS_SUCCESSFUL @a the_tod references a valid time of day.
  * @retval RTEMS_INVALID_CLOCK @a the_tod references an invalid time of day.
  * @retval RTEMS_INVALID_ADDRESS @a the_tod reference is @c NULL.
  */
 rtems_status_code _TOD_Validate(
-  const rtems_time_of_day *the_tod
+  const rtems_time_of_day *the_tod,
+  uint32_t                 ticks_mask
 );
 
 /**
diff --git a/cpukit/include/rtems/rtems/tasks.h b/cpukit/include/rtems/rtems/tasks.h
index be95768d4a..8b5912bcf9 100644
--- a/cpukit/include/rtems/rtems/tasks.h
+++ b/cpukit/include/rtems/rtems/tasks.h
@@ -2071,7 +2071,7 @@ rtems_status_code rtems_task_wake_after( rtems_interval ticks );
  *   occur.
  * @endparblock
  */
-rtems_status_code rtems_task_wake_when( rtems_time_of_day *time_buffer );
+rtems_status_code rtems_task_wake_when( const rtems_time_of_day *time_buffer );
 
 /* Generated from spec:/rtems/task/if/get-scheduler */
 
diff --git a/cpukit/rtems/src/clockset.c b/cpukit/rtems/src/clockset.c
index df163531a7..07384290b8 100644
--- a/cpukit/rtems/src/clockset.c
+++ b/cpukit/rtems/src/clockset.c
@@ -34,7 +34,7 @@ rtems_status_code rtems_clock_set(
   struct timespec   tod_as_timespec;
   ISR_lock_Context  lock_context;
 
-  status = _TOD_Validate( tod );
+  status = _TOD_Validate( tod, TOD_ENABLE_TICKS_VALIDATION );
 
   if ( status != RTEMS_SUCCESSFUL ) {
     return status;
diff --git a/cpukit/rtems/src/clocktodvalidate.c b/cpukit/rtems/src/clocktodvalidate.c
index 95c8e77c37..41a1167287 100644
--- a/cpukit/rtems/src/clocktodvalidate.c
+++ b/cpukit/rtems/src/clocktodvalidate.c
@@ -36,7 +36,8 @@ const uint32_t   _TOD_Days_per_month[ 2 ][ 13 ] = {
 };
 
 rtems_status_code _TOD_Validate(
-  const rtems_time_of_day *the_tod
+  const rtems_time_of_day *the_tod,
+  uint32_t                 ticks_mask
 )
 {
   uint32_t   days_in_month;
@@ -48,7 +49,7 @@ rtems_status_code _TOD_Validate(
 
   ticks_per_second = rtems_clock_get_ticks_per_second();
 
-  if ((the_tod->ticks  >= ticks_per_second)       ||
+  if ( ( ( the_tod->ticks & ticks_mask ) >= ticks_per_second ) ||
       (the_tod->second >= TOD_SECONDS_PER_MINUTE) ||
       (the_tod->minute >= TOD_MINUTES_PER_HOUR)   ||
       (the_tod->hour   >= TOD_HOURS_PER_DAY)      ||
diff --git a/cpukit/rtems/src/taskwakewhen.c b/cpukit/rtems/src/taskwakewhen.c
index a25204ad01..4dfa6dfef2 100644
--- a/cpukit/rtems/src/taskwakewhen.c
+++ b/cpukit/rtems/src/taskwakewhen.c
@@ -27,7 +27,7 @@
 #include <rtems/score/watchdogimpl.h>
 
 rtems_status_code rtems_task_wake_when(
-  rtems_time_of_day *time_buffer
+  const rtems_time_of_day *time_buffer
 )
 {
   uint32_t          seconds;
@@ -38,11 +38,7 @@ rtems_status_code rtems_task_wake_when(
   if ( !_TOD_Is_set() )
     return RTEMS_NOT_DEFINED;
 
-  if ( !time_buffer )
-    return RTEMS_INVALID_ADDRESS;
-
-  time_buffer->ticks = 0;
-  status = _TOD_Validate( time_buffer );
+  status = _TOD_Validate( time_buffer, TOD_DISABLE_TICKS_VALIDATION );
 
   if ( status != RTEMS_SUCCESSFUL ) {
     return status;
diff --git a/cpukit/rtems/src/timercreate.c b/cpukit/rtems/src/timercreate.c
index bd9421c440..59fa353b22 100644
--- a/cpukit/rtems/src/timercreate.c
+++ b/cpukit/rtems/src/timercreate.c
@@ -141,7 +141,7 @@ rtems_status_code _Timer_Fire_when(
   if ( !routine )
     return RTEMS_INVALID_ADDRESS;
 
-  status = _TOD_Validate( wall_time );
+  status = _TOD_Validate( wall_time, TOD_ENABLE_TICKS_VALIDATION );
 
   if ( status != RTEMS_SUCCESSFUL ) {
     return status;