filehandler.h

Linux下比较早的基于命令行的DVD播放器

//
// Copyright (c) 2003 by Istv醤 V醨adi
//
// This file is part of dxr3Player, a DVD player written specifically 
// for the DXR3 (aka Hollywood+) decoder card.

// This program is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation; either version 2 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

#ifndef DXR3PLAYER_DVD_FILEHANDLER_H
#define DXR3PLAYER_DVD_FILEHANDLER_H
//------------------------------------------------------------------------------

#include <cstdlib>
#include <cassert>

//------------------------------------------------------------------------------

namespace dvd {

//------------------------------------------------------------------------------

/**
 * Base class for DVD file handlers. It is reference counted.
 */
class FileHandler
{
private:
    /**
     * The reference counter.
     */
    size_t refCount;

protected:
    /**
     * Construct the file handler. The reference count will be set to 0.
     */
    FileHandler();

public:
    /**
     * Virtual destructor. Should be called with a reference count of 0.
     */
    virtual ~FileHandler();

    /**
     * Get the length of the file.
     */
    virtual size_t getLength() = 0;
    
    /**
     * Read the given number of sectors from the given offset into the
     * given buffer.
     */
    virtual void readSectors(void* dest, size_t offset, size_t numSectors)  = 0;

    /**
     * Increment the reference count.
     */
    void addReference();

    /**
     * Decrement the reference count.
     *
     * @return the number of remaining references.
     */
    size_t removeReference();
};

//------------------------------------------------------------------------------
// Inline definitions
//------------------------------------------------------------------------------

inline FileHandler::FileHandler() : refCount(0)
{
}

//------------------------------------------------------------------------------

inline FileHandler::~FileHandler() 
{
    assert(refCount==0);
}

//------------------------------------------------------------------------------

inline void FileHandler::addReference()
{
    ++refCount;
}

//------------------------------------------------------------------------------

inline size_t FileHandler::removeReference()
{
    assert(refCount>0);
    return --refCount;
}

//------------------------------------------------------------------------------

} /* namespace dvd */

//------------------------------------------------------------------------------
#endif // DXR3PLAYER_DVD_FILEHANDLER_H

// Local variables:
// mode: c++
// End: