On 23/08/2014 1:12 am, Sebastian Huber wrote:
Add rtems_clock_ticks_later(), rtems_clock_ticks_later_us() and
rtems_clock_ticks_later_us().
FIXME: Patch is incomplete. Documentation and tests are missing. Just
for API review.
---
cpukit/rtems/include/rtems/rtems/clock.h | 66 ++++++++++++++++++++++++++++++++
1 file changed, 66 insertions(+)
diff --git a/cpukit/rtems/include/rtems/rtems/clock.h
b/cpukit/rtems/include/rtems/rtems/clock.h
index ff71665..cee930e 100644
--- a/cpukit/rtems/include/rtems/rtems/clock.h
+++ b/cpukit/rtems/include/rtems/rtems/clock.h
@@ -34,6 +34,7 @@
#include <rtems/score/tod.h>
#include <rtems/rtems/status.h>
#include <rtems/rtems/types.h>
+#include <rtems/config.h>
#include <sys/time.h> /* struct timeval */
@@ -160,6 +161,71 @@ RTEMS_INLINE_ROUTINE rtems_interval
rtems_clock_get_ticks_since_boot(void)
}
/**
+ * @brief Returns the ticks counter value delta ticks in the future.
+ *
+ * @param[in] delta The ticks delta value.
+ *
+ * @return The tick counter value delta ticks in the future.
+ */
+RTEMS_INLINE_ROUTINE rtems_interval rtems_clock_ticks_later(
+ rtems_interval delta
+)
+{
+ return _Watchdog_Ticks_since_boot + delta;
+}
+
+/**
+ * @brief Returns the ticks counter value at least delta microseconds in the
+ * future.
+ *
+ * @param[in] delta The delta value in microseconds.
+ *
+ * @return The tick counter value at least delta microseconds in the future.
+ */
+RTEMS_INLINE_ROUTINE rtems_interval rtems_clock_ticks_later_us(
This should be rtems_clock_ticks_later_usec. When I first saw this I
though it meant 'us' as in 'you and me'.
The calls names make sense from a programming point of view but from a
user point of view they are sort of forwards and backwards. For example
rtems_clock_ticks_later_us is the "the clock tick so many micro-seconds
later where later implies now" or 'rtems_clock_tick_usecs_later' and
following this I suppose 'rtems_clock_ticks_later' becomes
'rtems_clock_tick_ticks_later' ?
+ rtems_interval delta
+)
+{
+ rtems_interval us_per_tick = rtems_configuration_get_microseconds_per_tick();
+
+ return _Watchdog_Ticks_since_boot + (delta + us_per_tick - 1) / us_per_tick;
+}
+
+/**
+ * @brief Returns true if the current ticks counter value indicates a time
+ * before the time specified by the ticks value and false otherwise.
+ *
+ * @param[in] ticks The ticks value.
+ *
+ * This can be used to write busy loops with a timeout.
+ *
+ * @code
+ * status busy( void )
+ * {
+ * rtems_interval timeout = rtems_clock_ticks_later_us( 10000 );
+ *
+ * do {
+ * if ( ok() ) {
+ * return success;
+ * }
+ * } while ( rtems_clock_ticks_before( timeout ) );
+ *
+ * return timeout;
+ * }
+ * @endcode
+ *
+ * @retval true The current ticks counter value indicates a time before the
+ * time specified by the ticks value.
+ * @retval false Otherwise.
+ */
+RTEMS_INLINE_ROUTINE bool rtems_clock_ticks_before(
And so should this become 'rtems_clock_tick_ticks_before' ?
Which then makes be wonder if 'rtems_clock_tick_ticks_later' becomes
''rtems_clock_tick_ticks_after' and finally
''rtems_clock_tick_usecs_after', or does 'rtems_clock_tick_ticks_before'
become 'rtems_clock_tick_ticks_earlier' ?
Is there a rtems_clock_tick_usecs_earlier ?
Chris
+ rtems_interval ticks
+)
+{
+ return ( (int32_t) ticks - (int32_t) _Watchdog_Ticks_since_boot ) > 0;
+}
+
+/**
* @brief Obtain Ticks Per Seconds
*
* This routine implements the rtems_clock_get_ticks_per_second
_______________________________________________
devel mailing list
devel@rtems.org
http://lists.rtems.org/mailman/listinfo/devel
