L_SetFilterHeartbeatCallback

// Call this method with a very large and complex XLSX document and a timeout in seconds value 
// Returns true on success and false if aborted 
// For each page, the image is loaded and passed to the processImage action 
 
class Stopwatch 
{ 
   public: Stopwatch() 
   { 
#if !defined(FOR_UNIX) 
      LARGE_INTEGER li; 
      QueryPerformanceFrequency(&li); 
      _Frequency = (L_DOUBLE)li.QuadPart / 1000.0; 
#else 
      _Frequency = 1; 
#endif 
 
      Reset(); 
   } 
 
   public: L_VOID Reset() 
   { 
#if !defined(FOR_UNIX) 
      LARGE_INTEGER li; 
      QueryPerformanceCounter(&li); 
      _StartTime = (L_DOUBLE)li.QuadPart; 
#else 
      struct timespec li; 
      clock_gettime(CLOCK_REALTIME, &li); 
      _StartTime = ((L_DOUBLE)li.tv_sec * 1000.0) + ((L_DOUBLE)li.tv_nsec / 1.0e6); 
#endif 
   } 
 
   public: L_UINT ElapsedMilliseconds() 
   { 
      L_DOUBLE nowTime; 
 
#if !defined(FOR_UNIX) 
      LARGE_INTEGER li; 
      QueryPerformanceCounter(&li); 
      nowTime = (L_DOUBLE)li.QuadPart; 
#else 
      struct timespec li; 
      clock_gettime(CLOCK_REALTIME, &li); 
      nowTime = ((L_DOUBLE)li.tv_sec * 1000.0) + ((L_DOUBLE)li.tv_nsec / 1.0e6); 
#endif 
 
      L_DOUBLE interval = (nowTime - _StartTime) / _Frequency; 
      return (L_UINT)interval; 
   } 
 
   private: L_DOUBLE _Frequency; 
   private: L_DOUBLE _StartTime; 
}; 
 
class CallbackData 
{ 
   public: Stopwatch Stopwatch; 
   public: L_UINT TimeoutMilliseconds; 
}; 
 
static L_INT EXT_CALLBACK FilterHeartbeatCallback(L_VOID* /*data*/, L_VOID* userData) 
{ 
   // Abort if it has been more than timeoutSeconds since last operation 
   CallbackData* callbackData = reinterpret_cast<CallbackData*>(userData); 
   if(callbackData->Stopwatch.ElapsedMilliseconds() > callbackData->TimeoutMilliseconds) 
   { 
      return ERROR_USER_ABORT; 
   } 
   else 
   { 
      return SUCCESS; 
   } 
} 
 
typedef L_INT(*PROCESS_IMAGE)(BITMAPHANDLE* bitmapHandle, L_INT pageNumber); 
L_INT FilterHeartbeatExample(L_TCHAR* inputFileName, L_UINT timeoutSeconds, PROCESS_IMAGE processImage) 
{ 
   CallbackData callbackData; 
   callbackData.TimeoutMilliseconds = timeoutSeconds * 1000; 
   // This is the start time, we will reset this value 
   // anytime we start an operation 
   callbackData.Stopwatch.Reset(); 
 
   // Set the callback 
   L_INT ret = L_SetFilterHeartbeatCallback(FilterHeartbeatCallback, &callbackData); 
 
   // Reset the start time 
   callbackData.Stopwatch.Reset(); 
 
   // First, get information on the file to get the number of pages 
   int pageCount = 0; 
   FILEINFO fileInfo; 
   memset(&fileInfo, 0, sizeof(FILEINFO)); 
   ret = L_FileInfo(inputFileName, &fileInfo, sizeof(FILEINFO), FILEINFO_TOTALPAGES, NULL); 
 
   // If L_FileInfo took more than timeoutSeconds then it returns ERROR_USER_ABORT 
   if(ret == ERROR_USER_ABORT) 
   { 
      printf("Aborted\n"); 
   } 
 
   // Fail 
   if(ret != SUCCESS) 
   { 
      L_SetFilterHeartbeatCallback(NULL, NULL); 
      return ret; 
   } 
 
   // Now load all the pages 
 
   LOADFILEOPTION loadFileOption; 
   memset(&loadFileOption, 0, sizeof(LOADFILEOPTION)); 
   L_GetDefaultLoadFileOption(&loadFileOption, sizeof(LOADFILEOPTION)); 
 
   for(L_INT pageNumber = 1; pageNumber <= pageCount; pageNumber++) 
   { 
      loadFileOption.PageNumber = pageNumber; 
 
      // Reset the start time 
      callbackData.Stopwatch.Reset(); 
      BITMAPHANDLE bitmapHandle; 
      memset(&bitmapHandle, 0, sizeof(BITMAPHANDLE)); 
      ret = L_LoadBitmap(inputFileName, &bitmapHandle, sizeof(BITMAPHANDLE), 0, ORDER_BGRORGRAY, &loadFileOption, NULL); 
 
      // If L_LoadBitmap took more than timeoutSeconds then it returns ERROR_USER_ABORT 
      if(ret == ERROR_USER_ABORT) 
      { 
         printf("Aborted\n"); 
      } 
 
      // Fail 
      if(ret != SUCCESS) 
      { 
         L_SetFilterHeartbeatCallback(NULL, NULL); 
         return ret; 
      } 
 
      // Did we abort? 
      // Process the image and then delete it 
      processImage(&bitmapHandle, pageNumber); 
 
      L_FreeBitmap(&bitmapHandle); 
   } 
 
   L_SetFilterHeartbeatCallback(NULL, NULL); 
 
   // We successfully loaded and processed all the pages from the file 
   return true; 
}