Chris@148: /* -*- c-basic-offset: 4 indent-tabs-mode: nil -*-  vi:set ts=8 sts=4 sw=4: */
Chris@148: 
Chris@148: /*
Chris@148:     Sonic Visualiser
Chris@148:     An audio file viewer and annotation editor.
Chris@148:     Centre for Digital Music, Queen Mary, University of London.
Chris@148:     This file copyright 2006 Chris Cannam.
Chris@148:     
Chris@148:     This program is free software; you can redistribute it and/or
Chris@148:     modify it under the terms of the GNU General Public License as
Chris@148:     published by the Free Software Foundation; either version 2 of the
Chris@148:     License, or (at your option) any later version.  See the file
Chris@148:     COPYING included with this distribution for more information.
Chris@148: */
Chris@148: 
Chris@148: #ifndef _MATRIX_FILE_CACHE_H_
Chris@148: #define _MATRIX_FILE_CACHE_H_
Chris@148: 
Chris@148: #include "base/ResizeableBitset.h"
Chris@148: 
Chris@148: #include "FileReadThread.h"
Chris@148: 
Chris@148: #include <sys/types.h>
Chris@148: #include <QString>
Chris@148: #include <QMutex>
Chris@148: #include <map>
Chris@148: 
Chris@148: class MatrixFile : public QObject
Chris@148: {
Chris@148:     Q_OBJECT
Chris@148: 
Chris@148: public:
Chris@148:     enum Mode { ReadOnly, ReadWrite };
Chris@148: 
Chris@148:     /**
Chris@148:      * Construct a MatrixFile object reading from and/or writing to
Chris@148:      * the matrix file with the given base name in the application's
Chris@148:      * temporary directory.
Chris@148:      *
Chris@148:      * If mode is ReadOnly, the file must exist and be readable.
Chris@148:      *
Chris@148:      * If mode is ReadWrite and the file does not exist, it will be
Chris@148:      * created.  If mode is ReadWrite and the file does exist, the
Chris@148:      * existing file will be used and the mode will be reset to
Chris@148:      * ReadOnly.  Call getMode() to check whether this has occurred
Chris@148:      * after construction.
Chris@148:      *
Chris@148:      * cellSize specifies the size in bytes of the object type stored
Chris@148:      * in the matrix.  For example, use cellSize = sizeof(float) for a
Chris@148:      * matrix of floats.  The MatrixFile object doesn't care about the
Chris@148:      * objects themselves, it just deals with raw data of a given size.
Chris@148:      *
Chris@148:      * If eagerCache is true, blocks from the file will be cached for
Chris@148:      * read.  If eagerCache is false, only columns that have been set
Chris@148:      * by calling setColumnAt on this MatrixFile (i.e. columns for
Chris@148:      * which haveSetColumnAt returns true) will be cached.
Chris@148:      */
Chris@148:     MatrixFile(QString fileBase, Mode mode, size_t cellSize, bool eagerCache);
Chris@148:     virtual ~MatrixFile();
Chris@148: 
Chris@148:     Mode getMode() const { return m_mode; }
Chris@148: 
Chris@148:     size_t getWidth() const { return m_width; }
Chris@148:     size_t getHeight() const { return m_height; }
Chris@148:     size_t getCellSize() const { return m_cellSize; }
Chris@148:     
Chris@148:     void resize(size_t width, size_t height);
Chris@148:     void reset();
Chris@148: 
Chris@148:     bool haveSetColumnAt(size_t x) const { return m_columnBitset->get(x); }
Chris@148:     void getColumnAt(size_t x, void *data);
Chris@148:     void setColumnAt(size_t x, const void *data);
Chris@148: 
Chris@148:     void suspend();
Chris@148: 
Chris@148: protected:
Chris@148:     int     m_fd;
Chris@148:     Mode    m_mode;
Chris@148:     int     m_flags;
Chris@148:     mode_t  m_fmode;
Chris@148:     size_t  m_cellSize;
Chris@148:     size_t  m_width;
Chris@148:     size_t  m_height;
Chris@148:     size_t  m_headerSize;
Chris@148:     QString m_fileName;
Chris@148:     size_t  m_defaultCacheWidth;
Chris@148:     size_t  m_prevX;
Chris@148: 
Chris@148:     struct Cache {
Chris@148:         size_t x;
Chris@148:         size_t width;
Chris@148:         char *data;
Chris@148:     };
Chris@148: 
Chris@148:     Cache m_cache;
Chris@148:     bool  m_eagerCache;
Chris@148: 
Chris@148:     bool getFromCache(size_t x, size_t ystart, size_t ycount, void *data);
Chris@148:     void primeCache(size_t x, bool left);
Chris@148: 
Chris@148:     void resume();
Chris@148: 
Chris@148:     bool seekTo(size_t x, size_t y);
Chris@148: 
Chris@148:     static FileReadThread *m_readThread;
Chris@148:     int m_requestToken;
Chris@148: 
Chris@148:     size_t m_requestingX;
Chris@148:     size_t m_requestingWidth;
Chris@148:     char *m_spareData;
Chris@148: 
Chris@148:     static std::map<QString, int> m_refcount;
Chris@148:     static QMutex m_refcountMutex;
Chris@148:     QMutex m_fdMutex;
Chris@148:     QMutex m_cacheMutex;
Chris@148: 
Chris@148:     typedef std::map<QString, ResizeableBitset *> ResizeableBitsetMap;
Chris@148:     static ResizeableBitsetMap m_columnBitsets;
Chris@148:     static QMutex m_columnBitsetWriteMutex;
Chris@148:     ResizeableBitset *m_columnBitset;
Chris@148: };
Chris@148: 
Chris@148: #endif
Chris@148: