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-rw-r--r--cpukit/posix/src/posixtimespecabsolutetimeout.c88
1 files changed, 88 insertions, 0 deletions
diff --git a/cpukit/posix/src/posixtimespecabsolutetimeout.c b/cpukit/posix/src/posixtimespecabsolutetimeout.c
new file mode 100644
index 0000000000..27d5db5abe
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+++ b/cpukit/posix/src/posixtimespecabsolutetimeout.c
@@ -0,0 +1,88 @@
+/*
+ * Convert abstime timeout to ticks
+ */
+
+/*
+ * 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 <stdarg.h>
+
+#include <errno.h>
+#include <fcntl.h>
+#include <pthread.h>
+#include <semaphore.h>
+#include <limits.h>
+
+#include <rtems/system.h>
+#include <rtems/score/object.h>
+#include <rtems/posix/semaphore.h>
+#include <rtems/posix/time.h>
+#include <rtems/seterr.h>
+
+/*
+ * The abstime is a walltime. We turn it into an interval.
+ */
+POSIX_Absolute_timeout_conversion_results_t _POSIX_Absolute_timeout_to_ticks(
+ const struct timespec *abstime,
+ Watchdog_Interval *ticks_out
+)
+{
+ struct timespec current_time;
+ struct timespec difference;
+
+
+ /*
+ * Make sure there is always a value returned.
+ */
+ *ticks_out = 0;
+
+ /*
+ * Is the absolute time even valid?
+ */
+ if ( !_Timespec_Is_valid(abstime) )
+ return POSIX_ABSOLUTE_TIMEOUT_INVALID;
+
+ /*
+ * Is the absolute time in the past?
+ */
+ _TOD_Get( &current_time );
+
+ if ( _Timespec_Less_than( abstime, &current_time ) )
+ return POSIX_ABSOLUTE_TIMEOUT_IS_IN_PAST;
+
+ /*
+ * How long until the requested absolute time?
+ */
+ _Timespec_Subtract( &current_time, abstime, &difference );
+
+ /*
+ * Internally the SuperCore uses ticks, so convert to them.
+ */
+ *ticks_out = _Timespec_To_ticks( &difference );
+
+ /*
+ * If the difference was 0, then the future is now. It is so bright
+ * we better wear shades.
+ */
+ if ( !*ticks_out )
+ return POSIX_ABSOLUTE_TIMEOUT_IS_NOW;
+
+ /*
+ * This is the case we were expecting and it took this long to
+ * get here.
+ */
+ return POSIX_ABSOLUTE_TIMEOUT_IS_IN_FUTURE;
+}
+