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”

 /****************License************************************************
  *
  * Copyright 2000-2003.  ScanSoft, Inc.    
  *
  * Use of this software is subject to notices and obligations set forth 
  * in the SpeechWorks Public License - Software Version 1.2 which is 
  * included with this software. 
  *
  * ScanSoft is a registered trademark of ScanSoft, Inc., and OpenSpeech, 
  * SpeechWorks and the SpeechWorks logo are registered trademarks or 
  * trademarks of SpeechWorks International, Inc. in the United States 
  * and other countries.
  *
  ***********************************************************************/
 

 /*****************************************************************************
  *****************************************************************************
  * SBtrd API implementation
  *
  * This provides the Linux implementation of the VXItrd API for basic
  * thread operations and locks. Unlike most of the other VXI APIs,
  * this is implemented in a library (on Windows a DLL with a specific
  * name, on other operating systems as a static, shared, or dynamic
  * library). Implementations of this API are operating system
  * dependant.
  *
  * To avoid cyclic dependancies, this does not perform logging. Clients
  * must do error logging themselves based on passed return codes.
  *
  *****************************************************************************
  *****************************************************************************/
 
 
 
 // -----1=0-------2=0-------3=0-------4=0-------5=0-------6=0-------7=0-------8
 
 
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include <signal.h>
 #include <pthread.h>
 #include <sys/time.h>
 #include <sys/types.h>
 
 #define VXITRD_EXPORTS
 #include "VXItrd.h"                   // Header for this API
 
 #ifndef NDEBUG
 #include <assert.h>
 #endif
 
 extern "C" {
 struct VXItrdMutex {
   pthread_mutex_t mutex;
 #if ( ! defined(NDEBUG) ) && ( ! defined(VXITRD_RECURSIVE_MUTEX) )
   volatile bool locked;
 #endif
 };
 }
 
 typedef enum VXItrdThreadState {
   STATE_STARTING = 0,
   STATE_RUNNING = 1,
   STATE_EXITED = 2
 } VXItrdThreadState;
 
 extern "C" {
 struct VXItrdThread {
   pthread_t thread;                       // Thread handle
   volatile VXItrdThreadState state;       // Thread state
   VXItrdMutex *refCountMutex;             // For reference count protection
   volatile VXIulong refCount;             // References to this structure
   VXItrdThreadStartFunc thread_function;  // user's thread function
   VXItrdThreadArg thread_arg;             // user's thread argument
 };
 }
 
 extern "C" {
 struct VXItrdTimer {
   volatile VXIbool isSleeping;  /* If 1, thread is currently sleeping */
   volatile VXIbool wakeUp;      /* If 1, thread will ignore the next Sleep() */
 };
 }
 
 static VXIint32 g_threadStackSize = 0;
 
 // -----1=0-------2=0-------3=0-------4=0-------5=0-------6=0-------7=0-------8
 
 
 /**
  * Internal utility function for sleeping
  */
 static VXItrdResult VXItrdSleep(VXIint millisecondDelay)
 {
   // Do not want to use usleep( ), non-portable and it is usually implemented
   // via signals which may mess up other software in the system which is
   // also trying to use signals. Note that it is very important to set up
   // the timer each time as on some OSes (like Linux) the timeout var is
   // modified to indicate the actual time slept.
   struct timeval timeout;
   timeout.tv_sec = 0;
   timeout.tv_usec = millisecondDelay * 1000;
   if (select (0, NULL, NULL, NULL, &timeout) < 0)
     return VXItrd_RESULT_SYSTEM_ERROR;
 
   return VXItrd_RESULT_SUCCESS;
 }
 
 
 /**
  * Creates a new mutex initialized to the unlocked state.  If the calling
  * thread terminates, the created mutex is not automatically deallocated as
  * it may be shared among multiple threads.
  *
  * @return -1 Fatal error (ex: system lacks necessary resources for creation)
  *           0 Success; valid mutex has been created
  */
 VXITRD_API VXItrdResult VXItrdMutexCreate(VXItrdMutex **mutex)
 {
   if (mutex == NULL) 
     return VXItrd_RESULT_INVALID_ARGUMENT;
 
   *mutex = NULL;
   
   // Create the wrapper object */
   VXItrdMutex *result = new VXItrdMutex;
   if (result == NULL)
     return VXItrd_RESULT_OUT_OF_MEMORY;
 #if ( ! defined(NDEBUG) ) && ( ! defined(VXITRD_RECURSIVE_MUTEX) )
   result->locked = false;
 #endif
 
   // Create the critical section */
   int rc;
   pthread_mutexattr_t mutexattr;
   
   // Create and configure mutex attributes for recursive mutex
   rc = pthread_mutexattr_init(&mutexattr);
   if (rc != 0) {
     delete result;
     return VXItrd_RESULT_NON_FATAL_ERROR;
   }
          
 #ifndef _unixware7_
   rc = pthread_mutexattr_settype(&mutexattr, PTHREAD_MUTEX_RECURSIVE);
   if (rc != 0) {
     pthread_mutexattr_destroy(&mutexattr);
     delete result;
     return VXItrd_RESULT_NON_FATAL_ERROR;
   }
 #endif
 
   // Initialize mutex with attributes
   rc = pthread_mutex_init(&result->mutex, &mutexattr);
   if (rc != 0) {
     pthread_mutexattr_destroy(&mutexattr);
     delete result;
     return VXItrd_RESULT_NON_FATAL_ERROR;
   }
 
   rc = pthread_mutexattr_destroy(&mutexattr);
   if (rc != 0) {
     pthread_mutex_destroy(&result->mutex);
     delete result;
     return VXItrd_RESULT_NON_FATAL_ERROR;
   }
 
   *mutex = result;
   return VXItrd_RESULT_SUCCESS;
 }
 
 
 /**
  * Deletes an existing mutex.  It is illegal to delete a locked mutex.
  *
  * @return -1 Fatal error (ex: invalid mutex)
  *          0 Success; mutex has been destroyed
  *          1 Mutex is locked
  */
 VXITRD_API VXItrdResult VXItrdMutexDestroy(VXItrdMutex **mutex)
 {
   if ((mutex == NULL) || (*mutex == NULL))
     return VXItrd_RESULT_INVALID_ARGUMENT;
 
 #if ( ! defined(NDEBUG) ) && ( ! defined(VXITRD_RECURSIVE_MUTEX) )
   // Check the lock state
   if ( (*mutex)->locked ) {
     assert ("VXItrdMutexDestroy( ) on locked mutex" == NULL);
     return VXItrd_RESULT_FATAL_ERROR;
   }
 #endif
 
   int rc = pthread_mutex_destroy(&(*mutex)->mutex);
   if (rc != 0) {
     return VXItrd_RESULT_NON_FATAL_ERROR;
   }
   
   delete *mutex;
   *mutex = NULL;
 
   return VXItrd_RESULT_SUCCESS;
 }
 
 
 /**
  * Locks an existing mutex.  If the mutex is already locked, the thread waits
  * for the mutex to become available.
  *
  * @return: -1 Fatal error (ex: invalid mutex or deadlock detected)
  *           0 Success; mutex is now locked
  *           1 Mutex already locked by current thread.
  */
 VXITRD_API VXItrdResult VXItrdMutexLock(VXItrdMutex *mutex)
 {
   if (mutex == NULL)
     return VXItrd_RESULT_INVALID_ARGUMENT;
   
   int rc = pthread_mutex_lock(&mutex->mutex);
   if (rc != 0) {
     return VXItrd_RESULT_NON_FATAL_ERROR;
   }
   
 #if ( ! defined(NDEBUG) ) && ( ! defined(VXITRD_RECURSIVE_MUTEX) )
   // Check the lock state
   if ( mutex->locked ) {
     // Should not be locking the same mutex twice, very OS dependant
     // and not gauranteed by VXItrdMutex
     assert ("VXItrdMutexLock( ) on already locked mutex" == NULL);
     return VXItrd_RESULT_FATAL_ERROR;
   } else {
     mutex->locked = true;
   }
 #endif
 
   return VXItrd_RESULT_SUCCESS;
 }
 
 
 /**
  * Unlocks a mutex owned by the thread.
  *
  * @return: -1 Fatal error (ex: invalid mutex)
  *           0 Success; mutex no longer owned by calling thread
  *           1 Mutex not owned by thread.
  */
 VXITRD_API VXItrdResult VXItrdMutexUnlock(VXItrdMutex *mutex)
 {
   if (mutex == NULL)
     return VXItrd_RESULT_INVALID_ARGUMENT;
 
 #if ( ! defined(NDEBUG) ) && ( ! defined(VXITRD_RECURSIVE_MUTEX) )
   // Check the lock state
   if ( ! mutex->locked ) {
     // Unlocking a mutex that wasn't locked
     assert ("VXItrdMutexUnlock( ) on unlocked mutex" == NULL);
     return VXItrd_RESULT_FATAL_ERROR;
   } else {
     mutex->locked = false;
   }
 #endif
 
   int rc = pthread_mutex_unlock(&mutex->mutex);
   if (rc != 0) {
     return VXItrd_RESULT_NON_FATAL_ERROR;
   }
 
   return VXItrd_RESULT_SUCCESS;
 }
 
 
 /**
  * Internal: wrapper functions for starting/cleaning up threads
  */
 static void VXItrdThreadCleanup(VXItrdThreadArg userData)
 {
   VXItrdThread *thread = (VXItrdThread *) userData;
 
   // No longer active
   thread->state = STATE_EXITED;
 
   // Free our copy of the thread handle
   VXItrdThreadDestroyHandle (&thread);
 }
 
 
 static VXITRD_DEFINE_THREAD_FUNC(VXItrdThreadStart, userData)
 {
   VXItrdThread *thread = (VXItrdThread *) userData;
 
   // Set the state and register a cleanup function to finish it,
   // required for ThreadJoin( ) support
   thread->state = STATE_RUNNING;
   pthread_cleanup_push(VXItrdThreadCleanup, userData);
 
   // Call the user function
   (*thread->thread_function)(thread->thread_arg);
 
   // Cleanup, the 1 to pop causes the cleanup function to be invoked
   pthread_cleanup_pop(1);
 
   return NULL;  // never gets called, just to eliminate compile warning
 }
 
 
 /**
  * Create a thread.  Note: thread values are not supported on OS/2.
  *    execution starts on the thread immediately. To pause execution 
  *    use a Mutex between the thread and the thread creator.
  *
  * @param   thread the thread object to be created
  * @param   thread_function the function for the thread to start execution on
  * @param   thread_arg the arguments to the thread function
  * @return  VXItrdResult of operation.  Return SUCCESS if thread has been 
  *          created and started.
  *
  */
 VXITRD_API 
 VXItrdResult VXItrdThreadCreate(VXItrdThread **thread,
 				VXItrdThreadStartFunc thread_function,
 				VXItrdThreadArg thread_arg)
 {
   if ((thread == NULL) || (thread_function == NULL))
     return VXItrd_RESULT_INVALID_ARGUMENT;
 
   *thread = NULL;
 
   // Create the wrapper object
   VXItrdThread *result = new VXItrdThread;
   if (result == NULL)
     return VXItrd_RESULT_OUT_OF_MEMORY;
 
   memset(result, 0, sizeof (VXItrdThread));
   result->state = STATE_STARTING;
   result->refCount = 1; // 1 for parent
   result->thread_function = thread_function;
   result->thread_arg = thread_arg;
 
   if (VXItrdMutexCreate(&result->refCountMutex) != VXItrd_RESULT_SUCCESS) {
     VXItrdThreadDestroyHandle(&result);
     return VXItrd_RESULT_SYSTEM_ERROR;
   }
 
   // construct thread attribute