1 files changed, 105 insertions, 0 deletions
diff --git a/cpukit/posix/src/ualarm.c b/cpukit/posix/src/ualarm.c
new file mode 100644
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+++ b/cpukit/posix/src/ualarm.c
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+/*
+ *  3.4.1 Schedule Alarm, P1003.1b-1993, p. 79
+ *
+ *  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 <pthread.h>
+/* #include <errno.h> */
+
+#include <rtems/system.h>
+#include <rtems/posix/pthread.h>
+#include <rtems/posix/psignal.h>
+#include <rtems/posix/time.h>
+
+/*PAGE
+ *
+ *  _POSIX_signals_Ualarm_TSR
+ */
+
+void _POSIX_signals_Ualarm_TSR(
+  Objects_Id      id __attribute__((unused)),
+  void           *argument __attribute__((unused))
+)
+{
+  /*
+   * Send a SIGALRM but if there is a problem, ignore it.
+   * It's OK, there isn't a way this should fail.
+   */
+  (void) kill( getpid(), SIGALRM );
+
+  /*
+   * If the reset interval is non-zero, reschedule ourselves.
+   */
+  _Watchdog_Reset( &_POSIX_signals_Ualarm_timer );
+}
+
+useconds_t ualarm(
+  useconds_t useconds,
+  useconds_t interval
+)
+{
+  useconds_t        remaining = 0;
+  Watchdog_Control *the_timer;
+  Watchdog_Interval ticks;
+  struct timespec   tp;
+
+  the_timer = &_POSIX_signals_Ualarm_timer;
+
+  /*
+   *  Initialize the timer used to implement alarm().
+   */
+
+  if ( !the_timer->routine ) {
+    _Watchdog_Initialize( the_timer, _POSIX_signals_Ualarm_TSR, 0, NULL );
+  } else {
+    Watchdog_States state;
+
+    state = _Watchdog_Remove( the_timer );
+    if ( (state == WATCHDOG_ACTIVE) || (state == WATCHDOG_REMOVE_IT) ) {
+      /*
+       *  The stop_time and start_time fields are snapshots of ticks since
+       *  boot.  Since alarm() is dealing in seconds, we must account for
+       *  this.
+       */
+
+      ticks = the_timer->initial;
+      ticks -= (the_timer->stop_time - the_timer->start_time);
+      /* remaining is now in ticks */
+
+      _Timespec_From_ticks( ticks, &tp );
+      remaining  = tp.tv_sec * TOD_MICROSECONDS_PER_SECOND;
+      remaining += tp.tv_nsec / 1000;
+    }
+  }
+
+  /*
+   *  If useconds is non-zero, then the caller wants to schedule
+   *  the alarm repeatedly at that interval.  If the interval is
+   *  less than a single clock tick, then fudge it to a clock tick.
+   */
+  if ( useconds ) {
+    Watchdog_Interval ticks;
+
+    tp.tv_sec = useconds / TOD_MICROSECONDS_PER_SECOND;
+    tp.tv_nsec = (useconds % TOD_MICROSECONDS_PER_SECOND) * 1000;
+    ticks = _Timespec_To_ticks( &tp );
+    if ( ticks == 0 )
+      ticks = 1;
+
+    _Watchdog_Insert_ticks( the_timer, _Timespec_To_ticks( &tp ) );
+  }
+
+  return remaining;
+}