QZipReader Class Reference

the QZipReader class provides a way to inspect the contents of a zip archive and extract individual files from it. More...

#include <qzipreader_p.h>

Classes
class	FileInfo
	Represents one entry in the zip table of contents. More...

Public Types
enum	Status {   NoError, FileReadError, FileOpenError, FilePermissionsError,   FileError }
	The following status values are possible: More...

Public Functions
void	close ()
	Close the zip file. More...
int	count () const
	Return the number of items in the zip archive. More...
QIODevice *	device () const
	Returns device used for reading zip archive. More...
FileInfo	entryInfoAt (int index) const
	Returns a FileInfo of an entry in the zipfile. More...
bool	exists () const
	Returns true if the file exists; otherwise returns false. More...
bool	extractAll (const QString &destinationDir) const
	Extracts the full contents of the zip file into destinationDir on the local filesystem. More...
QByteArray	fileData (const QString &fileName) const
	Fetch the file contents from the zip archive and return the uncompressed bytes. More...
QList< FileInfo >	fileInfoList () const
	Returns the list of files the archive contains. More...
bool	isReadable () const
	Returns true if the user can read the file; otherwise returns false. More...
	QZipReader (const QString &fileName, QIODevice::OpenMode mode=QIODevice::ReadOnly)
	Create a new zip archive that operates on the fileName. More...
	QZipReader (QIODevice *device)
	Create a new zip archive that operates on the archive found in device. More...
Status	status () const
	Returns a status code indicating the first error that was met by QZipReader, or QZipReader::NoError if no error occurred. More...
	~QZipReader ()
	Desctructor. More...

Properties
QZipReaderPrivate *	d

Detailed Description

the QZipReader class provides a way to inspect the contents of a zip archive and extract individual files from it.

Warning

This function is not part of the public interface.

Since

4.5

QZipReader can be used to read a zip archive either from a file or from any device. An in-memory QBuffer for instance. The reader can be used to read which files are in the archive using fileInfoList() and entryInfoAt() but also to extract individual files using fileData() or even to extract all files in the archive using extractAll()

Definition at line 66 of file qzipreader_p.h.

Enumerations

Status

enum QZipReader::Status

The following status values are possible:

• NoError No error occurred.

• FileReadError An error occurred when reading from the file.
• FileOpenError The file could not be opened.
• FilePermissionsError The file could not be accessed.
• FileError Another file error occurred.

Enumerator
NoError
FileReadError
FileOpenError
FilePermissionsError
FileError

Definition at line 104 of file qzipreader_p.h.

                {
        NoError,
        FileReadError,
        FileOpenError,
        FilePermissionsError,
        FileError
    };

Constructors and Destructors

QZipReader() [1/2]

QZipReader::QZipReader	(	const QString &	archive,
		QIODevice::OpenMode	mode = QIODevice::ReadOnly
	)

Create a new zip archive that operates on the fileName.

The file will be opened with the mode.

Definition at line 758 of file qzip.cpp.

{
    QScopedPointer<QFile> f(new QFile(archive));
    f->open(mode);
    QZipReader::Status status;
    if (f->error() == QFile::NoError)
        status = NoError;
    else {
        if (f->error() == QFile::ReadError)
            status = FileReadError;
        else if (f->error() == QFile::OpenError)
            status = FileOpenError;
        else if (f->error() == QFile::PermissionsError)
            status = FilePermissionsError;
        else
            status = FileError;
    }

    d = new QZipReaderPrivate(f.data(), /*ownDevice=*/true);
    f.take();
    d->status = status;
}

QZipReader() [2/2]

QZipReader::QZipReader ( QIODevice *  device )

explicit

Create a new zip archive that operates on the archive found in device.

You have to open the device previous to calling the constructor and only a device that is readable will be scanned for zip filecontent.

Definition at line 786 of file qzip.cpp.

    : d(new QZipReaderPrivate(device, /*ownDevice=*/false))
{
    Q_ASSERT(device);
}

~QZipReader()

QZipReader::~QZipReader

(

)

Desctructor.

Definition at line 795 of file qzip.cpp.

{
    close();
    delete d;
}

Functions

close()

void QZipReader::close

(

)

Close the zip file.

Definition at line 1021 of file qzip.cpp.

Referenced by ~QZipReader().

{
    d->device->close();
}

count()

int QZipReader::count

(

)

const

Return the number of items in the zip archive.

Definition at line 847 of file qzip.cpp.

{
    d->scanFiles();
    return d->fileHeaders.count();
}

device()

QIODevice * QZipReader::device

(

)

const

Returns device used for reading zip archive.

Definition at line 804 of file qzip.cpp.

Referenced by QZipWriterPrivate::addEntry(), QZipReaderPrivate::scanFiles(), and QZipPrivate::~QZipPrivate().

{
    return d->device;
}

entryInfoAt()

QZipReader::FileInfo QZipReader::entryInfoAt

(

int

index

)

const

Returns a FileInfo of an entry in the zipfile.

The index is the index into the directory listing of the zipfile. Returns an invalid FileInfo if index is out of boundaries.

See also

fileInfoList()

Definition at line 860 of file qzip.cpp.

{
    d->scanFiles();
    QZipReader::FileInfo fi;
    if (index >= 0 && index < d->fileHeaders.count())
        d->fillFileInfo(index, fi);
    return fi;
}

exists()

bool QZipReader::exists

(

)

const

Returns true if the file exists; otherwise returns false.

Definition at line 820 of file qzip.cpp.

{
    QFile *f = qobject_cast<QFile*> (d->device);
    if (f == 0)
        return true;
    return f->exists();
}

extractAll()

bool QZipReader::extractAll

(

const QString &

destinationDir

)

const

Extracts the full contents of the zip file into destinationDir on the local filesystem.

In case writing or linking a file fails, the extraction will be aborted.

Definition at line 944 of file qzip.cpp.

{
    QDir baseDir(destinationDir);

    // create directories first
    QList<FileInfo> allFiles = fileInfoList();
    foreach (FileInfo fi, allFiles) {
        const QString absPath = destinationDir + QDir::separator() + fi.filePath;
        if (fi.isDir) {
            if (!baseDir.mkpath(fi.filePath))
                return false;
            if (!QFile::setPermissions(absPath, fi.permissions))
                return false;
        }
    }

    // set up symlinks
    foreach (FileInfo fi, allFiles) {
        const QString absPath = destinationDir + QDir::separator() + fi.filePath;
        if (fi.isSymLink) {
            QString destination = QFile::decodeName(fileData(fi.filePath));
            if (destination.isEmpty())
                return false;
            QFileInfo linkFi(absPath);
            if (!QFile::exists(linkFi.absolutePath()))
                QDir::root().mkpath(linkFi.absolutePath());
            if (!QFile::link(destination, absPath))
                return false;
            /* cannot change permission of links
            if (!QFile::setPermissions(absPath, fi.permissions))
                return false;
            */
        }
    }

    foreach (FileInfo fi, allFiles) {
        const QString absPath = destinationDir + QDir::separator() + fi.filePath;
        if (fi.isFile) {
            QFile f(absPath);
            if (!f.open(QIODevice::WriteOnly))
                return false;
            f.write(fileData(fi.filePath));
            f.setPermissions(fi.permissions);
            f.close();
        }
    }

    return true;
}

fileData()

QByteArray QZipReader::fileData

(

const QString &

fileName

)

const

Fetch the file contents from the zip archive and return the uncompressed bytes.

Definition at line 872 of file qzip.cpp.

Referenced by extractAll().

{
    d->scanFiles();
    int i;
    for (i = 0; i < d->fileHeaders.size(); ++i) {
        if (QString::fromLocal8Bit(d->fileHeaders.at(i).file_name) == fileName)
            break;
    }
    if (i == d->fileHeaders.size())
        return QByteArray();

    FileHeader header = d->fileHeaders.at(i);

    int compressed_size = readUInt(header.h.compressed_size);
    int uncompressed_size = readUInt(header.h.uncompressed_size);
    int start = readUInt(header.h.offset_local_header);
    //qDebug("uncompressing file %d: local header at %d", i, start);

    d->device->seek(start);
    LocalFileHeader lh;
    d->device->read((char *)&lh, sizeof(LocalFileHeader));
    uint skip = readUShort(lh.file_name_length) + readUShort(lh.extra_field_length);
    d->device->seek(d->device->pos() + skip);

    int compression_method = readUShort(lh.compression_method);
    //qDebug("file=%s: compressed_size=%d, uncompressed_size=%d", fileName.toLocal8Bit().data(), compressed_size, uncompressed_size);

    //qDebug("file at %lld", d->device->pos());
    QByteArray compressed = d->device->read(compressed_size);
    if (compression_method == 0) {
        // no compression
        compressed.truncate(uncompressed_size);
        return compressed;
    } else if (compression_method == 8) {
        // Deflate
        //qDebug("compressed=%d", compressed.size());
        compressed.truncate(compressed_size);
        QByteArray baunzip;
        ulong len = qMax(uncompressed_size,  1);
        int res;
        do {
            baunzip.resize(len);
            res = inflate((uchar*)baunzip.data(), &len,
                          (uchar*)compressed.constData(), compressed_size);

            switch (res) {
            case Z_OK:
                if ((int)len != baunzip.size())
                    baunzip.resize(len);
                break;
            case Z_MEM_ERROR:
                qWarning("QZip: Z_MEM_ERROR: Not enough memory");
                break;
            case Z_BUF_ERROR:
                len *= 2;
                break;
            case Z_DATA_ERROR:
                qWarning("QZip: Z_DATA_ERROR: Input data is corrupted");
                break;
            }
        } while (res == Z_BUF_ERROR);
        return baunzip;
    }
    qWarning() << "QZip: Unknown compression method";
    return QByteArray();
}

fileInfoList()

QList< QZipReader::FileInfo > QZipReader::fileInfoList

(

)

const

Returns the list of files the archive contains.

Definition at line 831 of file qzip.cpp.

Referenced by extractAll().

{
    d->scanFiles();
    QList<QZipReader::FileInfo> files;
    for (int i = 0; i < d->fileHeaders.size(); ++i) {
        QZipReader::FileInfo fi;
        d->fillFileInfo(i, fi);
        files.append(fi);
    }
    return files;

}

isReadable()

bool QZipReader::isReadable

(

)

const

Returns true if the user can read the file; otherwise returns false.

Definition at line 812 of file qzip.cpp.

{
    return d->device->isReadable();
}

status()

QZipReader::Status QZipReader::status

(

)

const

Returns a status code indicating the first error that was met by QZipReader, or QZipReader::NoError if no error occurred.

Definition at line 1013 of file qzip.cpp.

Referenced by QZipWriterPrivate::addEntry(), QZipReader(), QZipWriter::QZipWriter(), and QZipReaderPrivate::scanFiles().

{
    return d->status;
}

Properties

d

QZipReaderPrivate* QZipReader::d

private

Definition at line 117 of file qzipreader_p.h.

Referenced by close(), count(), device(), entryInfoAt(), exists(), fileData(), fileInfoList(), isReadable(), QZipWriter::QZipWriter(), status(), and ~QZipReader().

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The documentation for this class was generated from the following files:

• /src/gui/text/qzipreader_p.h
• /src/gui/text/qzip.cpp