quazipfile.h

以mplayer为后端的QT gui播放器。

#ifndef QUA_ZIPFILE_H
#define QUA_ZIPFILE_H

/*
-- A kind of "standard" GPL license statement --
QuaZIP - a Qt/C++ wrapper for the ZIP/UNZIP package
Copyright (C) 2005-2008 Sergey A. Tachenov

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

-- A kind of "standard" GPL license statement ends here --

See COPYING file for GPL.

You are also permitted to use QuaZIP under the terms of LGPL (see
COPYING.LGPL). You are free to choose either license, but please note
that QuaZIP makes use of Qt, which is not licensed under LGPL. So if
you are using Open Source edition of Qt, you therefore MUST use GPL for
your code based on QuaZIP, since it would be also based on Qt in this
case. If you are Qt commercial license owner, then you are free to use
QuaZIP as long as you respect either GPL or LGPL for QuaZIP code.
 **/

#include <QIODevice>

#include "quazip.h"
#include "quazipnewinfo.h"

/// A file inside ZIP archive.
/** \class QuaZipFile quazipfile.h <quazip/quazipfile.h>
 * This is the most interesting class. Not only it provides C++
 * interface to the ZIP/UNZIP package, but also integrates it with Qt by
 * subclassing QIODevice. This makes possible to access files inside ZIP
 * archive using QTextStream or QDataStream, for example. Actually, this
 * is the main purpose of the whole QuaZIP library.
 *
 * You can either use existing QuaZip instance to create instance of
 * this class or pass ZIP archive file name to this class, in which case
 * it will create internal QuaZip object. See constructors' descriptions
 * for details. Writing is only possible with the existing instance.
 *
 * \section quazipfile-sequential Sequential or random-access?
 *
 * At the first thought, QuaZipFile has fixed size, the start and the
 * end and should be therefore considered random-access device. But
 * there is one major obstacle to making it random-access: ZIP/UNZIP API
 * does not support seek() operation and the only way to implement it is
 * through reopening the file and re-reading to the required position,
 * but this is prohibitely slow.
 *
 * Therefore, QuaZipFile is considered to be a sequential device. This
 * has advantage of availability of the ungetChar() operation (QIODevice
 * does not implement it properly for non-sequential devices unless they
 * support seek()). Disadvantage is a somewhat strange behaviour of the
 * size() and pos() functions. This should be kept in mind while using
 * this class.
 *
 **/
class QuaZipFile: public QIODevice {
  Q_OBJECT
  private:
    QuaZip *zip;
    QString fileName;
    QuaZip::CaseSensitivity caseSensitivity;
    bool raw;
    qint64 writePos;
    // these two are for writing raw files
    ulong uncompressedSize;
    quint32 crc;
    bool internal;
    int zipError;
    // these are not supported nor implemented
    QuaZipFile(const QuaZipFile& that);
    QuaZipFile& operator=(const QuaZipFile& that);
    void resetZipError()const {setZipError(UNZ_OK);}
    // const, but sets zipError!
    void setZipError(int zipError)const;
  protected:
    /// Implementation of the QIODevice::readData().
    qint64 readData(char *data, qint64 maxSize);
    /// Implementation of the QIODevice::writeData().
    qint64 writeData(const char *data, qint64 maxSize);
  public:
    /// Constructs a QuaZipFile instance.
    /** You should use setZipName() and setFileName() or setZip() before
     * trying to call open() on the constructed object.
     **/
    QuaZipFile();
    /// Constructs a QuaZipFile instance.
    /** \a parent argument specifies this object's parent object.
     *
     * You should use setZipName() and setFileName() or setZip() before
     * trying to call open() on the constructed object.
     **/
    QuaZipFile(QObject *parent);
    /// Constructs a QuaZipFile instance.
    /** \a parent argument specifies this object's parent object and \a
     * zipName specifies ZIP archive file name.
     *
     * You should use setFileName() before trying to call open() on the
     * constructed object.
     *
     * QuaZipFile constructed by this constructor can be used for read
     * only access. Use QuaZipFile(QuaZip*,QObject*) for writing.
     **/
    QuaZipFile(const QString& zipName, QObject *parent =NULL);
    /// Constructs a QuaZipFile instance.
    /** \a parent argument specifies this object's parent object, \a
     * zipName specifies ZIP archive file name and \a fileName and \a cs
     * specify a name of the file to open inside archive.
     *
     * QuaZipFile constructed by this constructor can be used for read
     * only access. Use QuaZipFile(QuaZip*,QObject*) for writing.
     *
     * \sa QuaZip::setCurrentFile()
     **/
    QuaZipFile(const QString& zipName, const QString& fileName,
        QuaZip::CaseSensitivity cs =QuaZip::csDefault, QObject *parent =NULL);
    /// Constructs a QuaZipFile instance.
    /** \a parent argument specifies this object's parent object.
     *
     * \a zip is the pointer to the existing QuaZip object. This
     * QuaZipFile object then can be used to read current file in the
     * \a zip or to write to the file inside it.
     *
     * \warning Using this constructor for reading current file can be
     * tricky. Let's take the following example:
     * \code
     * QuaZip zip("archive.zip");
     * zip.open(QuaZip::mdUnzip);
     * zip.setCurrentFile("file-in-archive");
     * QuaZipFile file(&zip);
     * file.open(QIODevice::ReadOnly);
     * // ok, now we can read from the file
     * file.read(somewhere, some);
     * zip.setCurrentFile("another-file-in-archive"); // oops...
     * QuaZipFile anotherFile(&zip);
     * anotherFile.open(QIODevice::ReadOnly);
     * anotherFile.read(somewhere, some); // this is still ok...
     * file.read(somewhere, some); // and this is NOT
     * \endcode
     * So, what exactly happens here? When we change current file in the
     * \c zip archive, \c file that references it becomes invalid
     * (actually, as far as I understand ZIP/UNZIP sources, it becomes
     * closed, but QuaZipFile has no means to detect it).
     *
     * Summary: do not close \c zip object or change its current file as
     * long as QuaZipFile is open. Even better - use another constructors
     * which create internal QuaZip instances, one per object, and
     * therefore do not cause unnecessary trouble. This constructor may
     * be useful, though, if you already have a QuaZip instance and do
     * not want to access several files at once. Good example:
     * \code
     * QuaZip zip("archive.zip");
     * zip.open(QuaZip::mdUnzip);
     * // first, we need some information about archive itself
     * QByteArray comment=zip.getComment();
     * // and now we are going to access files inside it
     * QuaZipFile file(&zip);
     * for(bool more=zip.goToFirstFile(); more; more=zip.goToNextFile()) {
     *   file.open(QIODevice::ReadOnly);
     *   // do something cool with file here
     *   file.close(); // do not forget to close!
     * }
     * zip.close();
     * \endcode
     **/
    QuaZipFile(QuaZip *zip, QObject *parent =NULL);
    /// Destroys a QuaZipFile instance.
    /** Closes file if open, destructs internal QuaZip object (if it
     * exists and \em is internal, of course).
     **/
    virtual ~QuaZipFile();
    /// Returns the ZIP archive file name.
    /** If this object was created by passing QuaZip pointer to the
     * constructor, this function will return that QuaZip's file name
     * (or null string if that object does not have file name yet).
     *
     * Otherwise, returns associated ZIP archive file name or null
     * string if there are no name set yet.
     *
     * \sa setZipName() getFileName()
     **/
    QString getZipName()const;
    /// Returns a pointer to the associated QuaZip object.
    /** Returns \c NULL if there is no associated QuaZip or it is
     * internal (so you will not mess with it).
     **/
    QuaZip* getZip()const;
    /// Returns file name.
    /** This function returns file name you passed to this object either
     * by using
     * QuaZipFile(const QString&,const QString&,QuaZip::CaseSensitivity,QObject*)
     * or by calling setFileName(). Real name of the file may differ in
     * case if you used case-insensitivity.
     *
     * Returns null string if there is no file name set yet. This is the
     * case when this QuaZipFile operates on the existing QuaZip object
     * (constructor QuaZipFile(QuaZip*,QObject*) or setZip() was used).
     * 
     * \sa getActualFileName
     **/
    QString getFileName()const {return fileName;}
    /// Returns case sensitivity of the file name.
    /** This function returns case sensitivity argument you passed to
     * this object either by using
     * QuaZipFile(const QString&,const QString&,QuaZip::CaseSensitivity,QObject*)
     * or by calling setFileName().
     *
     * Returns unpredictable value if getFileName() returns null string