C++ ArrayOf::reinit方法代码示例

/// Read the summary of this alias block from disk.  Since the audio data
/// is elsewhere, this consists of reading the entire summary file.
/// Fill with zeroes and return false if data are unavailable for any reason.
///
/// @param *data The buffer where the summary data will be stored.  It must
///              be at least mSummaryInfo.totalSummaryBytes long.
bool ODPCMAliasBlockFile::ReadSummary(ArrayOf<char> &data)
{
   data.reinit( mSummaryInfo.totalSummaryBytes );

   ODLocker locker{ &mFileNameMutex };
   wxFFile summaryFile(mFileName.GetFullPath(), wxT("rb"));

   if( !summaryFile.IsOpened() ) {

      // NEW model; we need to return valid data
      memset(data.get(), 0, mSummaryInfo.totalSummaryBytes);

      // we silence the logging for this operation in this object
      // after first occurrence of error; it's already reported and
      // spewing at the user will complicate the user's ability to
      // deal
      mSilentLog = TRUE;

      return false;
   }
   else
      mSilentLog = FALSE; // worked properly, any future error is NEW

   auto read = summaryFile.Read(data.get(), mSummaryInfo.totalSummaryBytes);

   if (read != mSummaryInfo.totalSummaryBytes) {
      memset(data.get(), 0, mSummaryInfo.totalSummaryBytes);
      return false;
   }
   
   FixSummary(data.get());

   return true;
}

/// Write the summary to disk, using the derived ReadData() to get the data
void ODPCMAliasBlockFile::WriteSummary()
{
   // To build the summary data, call ReadData (implemented by the
   // derived classes) to get the sample data
   // Call this first, so that in case of exceptions from ReadData, there is
   // no NEW output file
   SampleBuffer sampleData(mLen, floatSample);
   this->ReadData(sampleData.ptr(), floatSample, 0, mLen, true);

   ArrayOf< char > fileNameChar;
   FILE *summaryFile{};
   {
      //the mFileName path may change, for example, when the project is saved.
      //(it moves from /tmp/ to wherever it is saved to.
      ODLocker locker { &mFileNameMutex };

      //wxFFile is not thread-safe - if any error occurs in opening the file,
      // it posts a wxlog message which WILL crash
      // Audacity because it goes into the wx GUI.
      // For this reason I left the wxFFile method commented out. (mchinen)
      //    wxFFile summaryFile(mFileName.GetFullPath(), wxT("wb"));

      // ...and we use fopen instead.
      wxString sFullPath = mFileName.GetFullPath();
      fileNameChar.reinit( strlen(sFullPath.mb_str(wxConvFile)) + 1 );
      strcpy(fileNameChar.get(), sFullPath.mb_str(wxConvFile));
      summaryFile = fopen(fileNameChar.get(), "wb");
   }

   // JKC ANSWER-ME: Whay is IsOpened() commented out?
   if (!summaryFile){//.IsOpened() ){

      // Never silence the Log w.r.t write errors; they always count
      //however, this is going to be called from a non-main thread,
      //and wxLog calls are not thread safe.
      wxPrintf("Unable to write summary data to file: %s", fileNameChar.get());

      throw FileException{
         FileException::Cause::Read, wxFileName{ fileNameChar.get() } };
   }

   ArrayOf<char> cleanup;
   void *summaryData = CalcSummary(sampleData.ptr(), mLen,
                                            floatSample, cleanup);

   //summaryFile.Write(summaryData, mSummaryInfo.totalSummaryBytes);
   fwrite(summaryData, 1, mSummaryInfo.totalSummaryBytes, summaryFile);
   fclose(summaryFile);


    //     wxPrintf("write successful. filename: %s\n", fileNameChar);

   mSummaryAvailableMutex.Lock();
   mSummaryAvailable=true;
   mSummaryAvailableMutex.Unlock();
}

/// Read the summary of this alias block from disk.  Since the audio data
/// is elsewhere, this consists of reading the entire summary file.
/// Fill with zeroes and return false if data are unavailable for any reason.
///
/// @param *data The buffer where the summary data will be stored.  It must
///              be at least mSummaryInfo.totalSummaryBytes long.
bool ODDecodeBlockFile::ReadSummary(ArrayOf<char> &data)
{
   //I dont think we need to add a mutex here because only the main thread changes filenames and calls ReadSummary
   if(IsSummaryAvailable())
      return SimpleBlockFile::ReadSummary(data);

   data.reinit( mSummaryInfo.totalSummaryBytes );
   memset(data.get(), 0, mSummaryInfo.totalSummaryBytes);
   return false;
}

bool SilentBlockFile::ReadSummary(ArrayOf<char> &data)
{
   data.reinit( mSummaryInfo.totalSummaryBytes );
   memset(data.get(), 0, mSummaryInfo.totalSummaryBytes);
   return true;
}