msynch.nc

来自「tinyos最新版」· NC 代码 · 共 160 行

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/*
 * Authors:   Philip Levis
 * History:   July  19, 2002   Creation
 *	      March 10, 2004   Move Mate to Mate
 *
 */

/**
 * @author Philip Levis
 */


includes Mate;

module MSynch {
  provides interface MateSynch as Synch;
  uses {
    interface MateError;
    interface MateLocks as Locks;
  }
}


implementation {
	
  command bool Synch.isRunnable(MateContext* context, 
				MateLock* locks) {
    int8_t i;
    uint16_t neededLocks = (context->acquireSet);
    dbg(DBG_USR2, "VM: Checking whether context %i runnable: ", (int)context->which);

    for (i = 0; i < MATE_HEAPSIZE; i++) {
      if (neededLocks & (1 << i)) {
	if (call Locks.isLocked(locks, i)) {
	  dbg_clear(DBG_USR2, "no\n");
	  return FALSE;
	}
      }
    }
    dbg_clear(DBG_USR2, "yes\n");
    return TRUE;
  }

  command result_t Synch.obtainLocks(MateContext* caller, 
				     MateContext* obtainer, 
				     MateLock* locks) {
    int8_t i;
    uint16_t neededLocks = (obtainer->acquireSet);
    dbg(DBG_USR2, "VM: Attempting to obtain necessary locks for context %i.\n", obtainer->which);
    for (i = 0; i < MATE_HEAPSIZE; i++) {
      if (neededLocks & (1 << i)) {
	call Locks.lock(obtainer, locks, i);
      }
    }
    obtainer->acquireSet = 0;
    return SUCCESS;		
  }

  command result_t Synch.releaseLocks(MateContext* caller, 
				      MateContext* releaser, 
				      MateLock* locks) {
    int8_t i;
    uint16_t lockSet = (releaser->releaseSet);
    dbg(DBG_USR2, "VM: Attempting to release specified locks for context %i.\n", releaser->which);
    for (i = 0; i < MATE_HEAPSIZE; i++) {
      if (lockSet & (1 << i)) {
	call Locks.unlock(releaser, locks, i);
      }
    }
    releaser->releaseSet = 0;
    return SUCCESS;		
  }

  command result_t Synch.releaseAllLocks(MateContext* caller,
					 MateContext* releaser, 
					 MateLock* locks) {
    int8_t i;
    uint16_t lockSet = (releaser->heldSet);
    dbg(DBG_USR2, "VM: Attempting to release all locks for context %i.\n", releaser->which);
    for (i = 0; i < MATE_HEAPSIZE; i++) {
      if (lockSet & (1 << i)) {
	call Locks.unlock(releaser, locks, i);
      }
    }
    releaser->releaseSet = 0;
    return SUCCESS;
  }
}