conditionvariable.nc

tinyos2.0版本驱动

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/**
 * Interface for using Conddition Variables for synchronization 
 * with tosthreads.
 *
 * @author Kevin Klues <[e-mail]>
 */

#include "condvar.h"

interface ConditionVariable {
  /**
   * Reset a condition variable for use.
   * @param c The condition variable you would like to reset.
   */
  command void init(condvar_t* c);
  /**
   * Wait on a condition variable until one of the signal
   * calls unbocks me.  In the process, unlock the mutex 
   * passed in to me.
   * @param c The condition variable you would like to wait on.
   * @param m The mutex you would like to unlock
   */
  command void wait(condvar_t* c, mutex_t* m);
  /**
   * Signal the next thread waiting on this condition variable 
   * to continue execution.  To unblock all threads waiting on 
   * this condition vairable use signalAll().
   * @param c The condition variable associated with the thread 
   *          you would like to signal.
   */
  command void signalNext(condvar_t* c);
  /**
   * Signal all threads waiting on this condition variable 
   * to continue execution.  To unblock just the next thread
   * waiting on this condition vairable use signalNext().
   * @param c The condition variable associated with the thread 
   *          you would like to signal.
   */
  command void signalAll(condvar_t* c);
  /**
   * Query whether a condition variable is currently blocking 
   * any threads from executing.
   * @param c The cndition variable you would like to query.
   * @return  TRUE or FALSE
   */
  command bool isBlocking(condvar_t* c);
}