source: rtems/cpukit/score/src/watchdogadjusttochain.c @ 632e4306

/**
 *  @file watchdogadjusttochain.c
 *
 *  This is used by the Timer Server task.
 */

/*  COPYRIGHT (c) 1989-2009.
 *  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 <rtems/system.h>
#include <rtems/score/isr.h>
#include <rtems/score/watchdog.h>

void _Watchdog_Adjust_to_chain(
  Chain_Control               *header,
  Watchdog_Interval            units_arg,
  Chain_Control               *to_fire

)
{
  Watchdog_Interval  units = units_arg;
  ISR_Level          level;
  Watchdog_Control  *first; 
  
  if ( !units )
    return;
 
  _ISR_Disable( level );

  if ( !_Chain_Is_empty( header ) ) {
    while ( units ) {
      first = _Watchdog_First( header );

      /*
       *  If it is longer than "units" until the first element on the chain
       *  fires, then bump it and quit.
       */
      if ( units < first->delta_interval ) {
        first->delta_interval -= units;
        break;
      }

      /*
       *  The first set happens in less than units, so take all of them
       *  off the chain and adjust units to reflect this.
       */
      units -= first->delta_interval;
      first->delta_interval = 0;

      while (1) {
        _Chain_Extract_unprotected( &first->Node );
        _Chain_Append_unprotected( to_fire, &first->Node );

      _ISR_Flash( level );
   
        if ( _Chain_Is_empty( header ) )
          break;

        first = _Watchdog_First( header );
        if ( first->delta_interval != 0 )
          break;
      }
    }
  }
  _ISR_Enable( level );
}