ODPCMAliasBlockFile.h

Go to the documentation of this file.

/**********************************************************************
 
  Audacity: A Digital Audio Editor
 
  ODPCMAliasBlockFile.cpp
 
  Created by Michael Chinen (mchinen)
  Audacity(R) is copyright (c) 1999-2008 Audacity Team.
  License: GPL v2.  See License.txt.
 
******************************************************************//*******************************************************************/
 
 
 
 
 
 
#ifndef __AUDACITY_ODPCMALIASBLOCKFILE__
#define __AUDACITY_ODPCMALIASBLOCKFILE__
 
#include "PCMAliasBlockFile.h"
 
class ODPCMAliasBlockFile final : public PCMAliasBlockFile
{
 public:
   ODPCMAliasBlockFile(wxFileNameWrapper &&baseFileName,
                        wxFileNameWrapper &&aliasedFileName, sampleCount aliasStart,
                        size_t aliasLen, int aliasChannel);
   ODPCMAliasBlockFile(wxFileNameWrapper &&existingSummaryFileName,
                        wxFileNameWrapper &&aliasedFileName, sampleCount aliasStart,
                        size_t aliasLen, int aliasChannel,
                        float min, float max, float rms, bool summaryAvailable);
   virtual ~ODPCMAliasBlockFile();
 
   //checks to see if summary data has been computed and written to disk yet.  Thread safe.  Blocks if we are writing summary data.
   bool IsSummaryAvailable() const override;
 
   bool IsSummaryBeingComputed() override { return mSummaryBeingComputed; }
 
   //Calls that rely on summary files need to be overridden
   DiskByteCount GetSpaceUsage() const override;
   MinMaxRMS GetMinMaxRMS(
      size_t start, size_t len, bool mayThrow) const override;
   MinMaxRMS GetMinMaxRMS(bool mayThrow) const override;
   bool Read256(float *buffer, size_t start, size_t len) override;
   bool Read64K(float *buffer, size_t start, size_t len) override;
 
   BlockFilePtr Copy(wxFileNameWrapper &&fileName) override;
 
   void SaveXML(XMLWriter &xmlFile) override;
 
   static BlockFilePtr BuildFromXML(DirManager &dm, const wxChar **attrs);
 
   void Recover(void) override;
 
   void DoWriteSummary();
 
   void SetStart(sampleCount startSample){mStart = startSample;}
 
   sampleCount GetStart() const {return mStart;}
 
   void Lock() override;
 
   void Unlock() override;
 
   void SetClipOffset(sampleCount numSamples){mClipOffset= numSamples;}
 
   sampleCount GetClipOffset() const {return mClipOffset;}
 
   //returns the number of samples from the beginning of the track that this blockfile starts at
   sampleCount GetGlobalStart() const {return mClipOffset+mStart;}
 
   //returns the number of samples from the beginning of the track that this blockfile ends at
   sampleCount GetGlobalEnd() const {return mClipOffset+mStart+GetLength();}
 
 
   //Below calls are overridden just so we can take wxlog calls out, which are not threadsafe.
 
   size_t ReadData(samplePtr data, sampleFormat format,
                        size_t start, size_t len, bool mayThrow) const override;
 
   bool ReadSummary(ArrayOf<char> &data) override;
 
   void SetFileName(wxFileNameWrapper &&name) override;
   GetFileNameResult GetFileName() const override;
 
   //when the file closes, it locks the blockfiles, but only conditionally.
   // It calls this so we can check if it has been saved before.
   // not balanced by unlocking calls.
   void CloseLock() override;
 
   void LockRead() const override;
   void UnlockRead() const override;
 
protected:
   void WriteSummary() override;
   void *CalcSummary(samplePtr buffer, size_t len,
      sampleFormat format, ArrayOf<char> &cleanup) override;
 
  private:
 
   ODLock mWriteSummaryMutex;
 
   //need to protect this since it is changed from the main thread upon save.
   mutable ODLock mFileNameMutex;
 
   ODLock mAliasedFileNameMutex;
 
   //lock the read data - libsndfile can't handle two reads at once?
   mutable ODLock mReadDataMutex;
 
   mutable ODLock    mSummaryAvailableMutex;
   bool mSummaryAvailable;
   bool mSummaryBeingComputed;
   bool mHasBeenSaved;
 
   sampleCount mStart;
 
   sampleCount mClipOffset;
};
 
#endif