sbtrdpthreads.cpp

OSB-PIK-OpenVXI-3.0.0源代码 “中国XML论坛 - 专业的XML技术讨论区--XML在语音技术中的应用”

   pthread_attr_t thread_attr;
   int prc = pthread_attr_init(&thread_attr);
   if (prc != 0) {
     VXItrdThreadDestroyHandle(&result);
     return VXItrd_RESULT_NON_FATAL_ERROR;
   }
   
   // configure thread attribute
 #ifdef USE_DETACHED_THREADS
   prc = pthread_attr_setdetachstate(&thread_attr, PTHREAD_CREATE_DETACHED);
   if (prc != 0) {
     pthread_attr_destroy(&thread_attr);
     VXItrdThreadDestroyHandle(&result);
     return VXItrd_RESULT_NON_FATAL_ERROR;
   }
 #else
   // use joinable threads
   // this is default - no work required
 #endif
 
   // Set the thread's stack size. A zero value means 'let the OS decide'
   if (g_threadStackSize > 0)
     pthread_attr_setstacksize(&thread_attr, g_threadStackSize);
 
   // Start the thread using our wrapper function
   result->refCount++;  // for child
   prc = pthread_create(&result->thread, &thread_attr, VXItrdThreadStart,
                        (VXItrdThreadArg) result);
 
   pthread_attr_destroy(&thread_attr);
 
   if (prc != 0) {
     result->refCount--;
     VXItrdThreadDestroyHandle(&result);
     return VXItrd_RESULT_NON_FATAL_ERROR;
   }
 
   *thread = result;
 
   return VXItrd_RESULT_SUCCESS;
 }
 
 
 /**
  * Destroy a thread handle
  *
  * Note: this does NOT stop or destroy the thread, it just releases
  * the handle for accessing it. If this is not done, a memory leak
  * occurs, so if the creator of the thread never needs to communicate
  * with the thread again it should call this immediately after the
  * create if the create was successful.
  *
  * @param  thread  Handle to the thread to destroy
  *
  * @result VXItrdResult 0 on success 
  */
 VXITRD_API VXItrdResult VXItrdThreadDestroyHandle(VXItrdThread **thread)
 {
   if ((thread == NULL) || (*thread == NULL))
     return VXItrd_RESULT_INVALID_ARGUMENT;
 
   // Decrement ref count
   VXIulong refs = 0;
   if ((*thread)->refCountMutex) {
     VXItrdMutexLock ((*thread)->refCountMutex);
     (*thread)->refCount--;
     refs = (*thread)->refCount;
     VXItrdMutexUnlock ((*thread)->refCountMutex);
   }
 
   if (refs == 0) {
     // No longer needed
     if ((*thread)->refCountMutex)
       VXItrdMutexDestroy (&(*thread)->refCountMutex);
     delete *thread;
   }
 
   *thread = NULL;
 
   return VXItrd_RESULT_SUCCESS;
 }
 
 
 /**
  * Terminate a thread.  Called by the thread on exit.
  *
  * @param  status  Exit code for the thread
  * @result           N/A, never returns
  */
 VXITRD_API void VXItrdThreadExit(VXItrdThreadArg status)
 {
   pthread_exit(status);
 }
 
 
 /**
  * Causes the calling thread to wait for the termination of a specified
  *   'thread' with a specified timeout, in milliseconds. 
  *
  * @param   thread the 'thread' that is waited for its termination.
  * @param   status contains the exit value of the thread's start routine.
  * @return  VXItrdResult of operation.  Return SUCCESS if specified 'thread' 
  *          terminating.
  */
 VXITRD_API VXItrdResult VXItrdThreadJoin(VXItrdThread *thread,
 					 VXItrdThreadArg *status,
 					 long timeout)
 {
   if ((thread == NULL ) || (status == NULL) || (timeout < -1))
     return VXItrd_RESULT_INVALID_ARGUMENT;
 
   VXItrdResult rc = VXItrd_RESULT_SUCCESS;
   if (timeout == -1) {
     // Wait forever
     if (pthread_join(thread->thread, status) != 0)
       rc = VXItrd_RESULT_SYSTEM_ERROR;
   } else {
     // Wait with a timeout, we just do a polling implementation
     long remainingMsec = timeout;
     while ((remainingMsec > 0) && (thread->state != STATE_EXITED) &&
            (rc == VXItrd_RESULT_SUCCESS)) {
       if (remainingMsec > 50) {
         rc = VXItrdSleep (50);
         remainingMsec -= 50;
       } else {
         rc = VXItrdSleep (remainingMsec);
         remainingMsec = 0;
       }
     }
 
     if (rc == VXItrd_RESULT_SUCCESS) {
       if (thread->state == STATE_EXITED) {
         // Collect the thread
         if (pthread_join(thread->thread, status) != 0)
           rc = VXItrd_RESULT_SYSTEM_ERROR;
       } else {
         rc = VXItrd_RESULT_FAILURE;
       }
     }
   }
 
   return rc;
 }
 
 
 /**
  * Get the thread ID for the specified thread
  *
  * @param  thread   Handle to the thread to get the ID for
  *
  * @result   Thread ID number
  */
 VXITRD_API VXIthreadID VXItrdThreadGetIDFromHandle(VXItrdThread *thread)
 {
   if (thread == NULL) 
     return (VXIthreadID) -1;
 
   return thread->thread;
 }
 
 
 /**
  * Get the ID of the current handle.
  *
  * @return  The current thread handle identifier.
  *
  */
 VXITRD_API VXIthreadID VXItrdThreadGetID(void)
 {
   return pthread_self(); 
 }
 
 
 /**
  * Purpose Yield the process schedule in the current thread.
  *
  * @return  void
  *
  */
 VXITRD_API void VXItrdThreadYield(void)
 {
 #ifndef NDEBUG
   assert (sched_yield() == 0);
 #else
   sched_yield();
 #endif
 }
 
 
 /**
  * Create a timer
  *
  * @param   timer  a pointer to a timer
  * @return  VXItrdResult of operation.  Return SUCCESS if timer has been 
  *          created
  *
  */
 VXITRD_API VXItrdResult VXItrdTimerCreate(VXItrdTimer **timer)
 {
   if (timer == NULL) 
     return VXItrd_RESULT_INVALID_ARGUMENT;
   
   VXItrdTimer *result = new VXItrdTimer;
   if (result == NULL)
     return VXItrd_RESULT_OUT_OF_MEMORY;
 
   // Initialize all data
   result->isSleeping = FALSE;
   result->wakeUp = FALSE;
 
   *timer = result;
 
   return VXItrd_RESULT_SUCCESS;
 }
 
 
 /**
  * Destroy a timer
  *
  * @param   timer  a pointer to a timer
  * @return  VXItrdResult of operation.  Return SUCCESS if timer has been 
  *          created
  *
  */
 VXITRD_API VXItrdResult VXItrdTimerDestroy(VXItrdTimer **timer)
 {
   if ((timer == NULL) || (*timer == NULL))
     return VXItrd_RESULT_INVALID_ARGUMENT;
 
   // Don't leave the corresponding thread in a suspended state.
   VXItrdResult rc = VXItrd_RESULT_SUCCESS;
   if ((*timer)->isSleeping) {
     VXItrdTimerWake(*timer);
     
     // Wait for the sleeping thread to wake up, note that on some OSes
     // like Linux the timeout is modified to give the actual amount of
     // time slept so need to re-initialize each time
     while (((*timer)->isSleeping) && 
            ((rc = VXItrdSleep (50)) == VXItrd_RESULT_SUCCESS))
       ; // keep going
   }
 
   delete *timer;
   *timer = NULL;
 
   return rc;
 }
 
 
 /**
  * Puts the current thread to sleep for a configurable duration.
  *    Due to other activities of the machine, the delay is the minimum
  *    length that the timer will wait.
  *
  * @param   timer  a pointer to a timer
  * @param   millisecondDelay  the minimum number of milliseconds to wait
  * @param   interrupted  a pointer (may optionally be NULL) indicating whether
  *            or not the sleep was interrupted by VXItrdTimerWake.
  * @return  VXItrdResult of operation.  Return SUCCESS if timer could sleep.
  *
  */
 VXITRD_API VXItrdResult VXItrdTimerSleep(VXItrdTimer *timer,
 					 VXIint millisecondDelay,
 					 VXIbool *interrupted)
 {
   if ((timer == NULL) || (millisecondDelay < 0)) 
     return VXItrd_RESULT_INVALID_ARGUMENT;
  
   if (timer->isSleeping == TRUE)
     return VXItrd_RESULT_FATAL_ERROR;
   timer->isSleeping = TRUE;
 
   // Sleep, we just do a polling implementation
   VXItrdResult rc = VXItrd_RESULT_SUCCESS;
   VXIint remainingMsec = millisecondDelay;
   while ((remainingMsec > 0) && (timer->wakeUp == FALSE) &&
          (rc == VXItrd_RESULT_SUCCESS)) {
     if (remainingMsec > 50) {
       rc = VXItrdSleep (50);
       remainingMsec -= 50;
     } else {
       rc = VXItrdSleep (remainingMsec);
       remainingMsec = 0;
     }
   }
 
   if (timer->wakeUp) {
     if (interrupted)
       *interrupted = TRUE;
     timer->wakeUp = FALSE;
   } else if (interrupted) {
     *interrupted = FALSE;
   }
 
   timer->isSleeping = FALSE;
   return VXItrd_RESULT_SUCCESS;
 }
 
 
 /**
  * Wakes a sleeping thread, if the target is not already sleeping
  *    it immediately wakes when it tries to sleep the next time.
  *
  * @param   timer  a pointer to a timer
  * @return  VXItrdResult of operation.  Return SUCCESS if timer could wake.
  *
  */
 VXITRD_API VXItrdResult VXItrdTimerWake(VXItrdTimer *timer)
 {
   if (timer == NULL) 
     return VXItrd_RESULT_INVALID_ARGUMENT;
 
   timer->wakeUp = TRUE;
 
   return VXItrd_RESULT_SUCCESS;
 }
 
 
 /**
  * Initialize the TRD utilities library
  *
  * @param threadStackSize  Stack size to use when creating new threads.
  *                         Pass 0 to use the default (OS-specific) size,
  *                         usually this means new threads will use the
  *                         same stack size as the main (parent) process.
  *
  * @return VXItrd_RESULT_SUCCESS if sucess, different value on failure
  */
 VXITRD_API VXItrdResult VXItrdInit (VXIint32 threadStackSize)
 {
   g_threadStackSize = threadStackSize;
   return VXItrd_RESULT_SUCCESS;
 }
 
 
 /**
  * Shutdown the TRD utilities library
  *
  * @return VXItrd_RESULT_SUCCESS if sucess, different value on failure
  */
 VXITRD_API VXItrdResult VXItrdShutDown ()
 {
   return VXItrd_RESULT_SUCCESS;
 }