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** this package.

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** Foundation and appearing in the file LICENSE.LGPL included in the

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****************************************************************************/

#include "qresource.h"

#include "qresource_p.h"

#include "qresource_iterator_p.h"

#include "qset.h"

#include "qhash.h"

#include "qmutex.h"

#include "qdebug.h"

#include "qlocale.h"

#include "qglobal.h"

#include "qvector.h"

#include "qdatetime.h"

#include "qbytearray.h"

#include "qstringlist.h"

#include <qshareddata.h>

#include <qplatformdefs.h>

#include "private/qabstractfileengine_p.h"

//#define DEBUG_RESOURCE_MATCH

QT_BEGIN_NAMESPACE

//resource glue

class QResourceRoot

{

    enum Flags

    {

        Compressed = 0x01,

        Directory = 0x02

    };

    const uchar *tree, *names, *payloads;

    inline int findOffset(int node) const { return node * 14; } //sizeof each tree element

    int hash(int node) const;

    QString name(int node) const;

    short flags(int node) const;

public:

    mutable QAtomicInt ref;

    inline QResourceRoot(): tree(0), names(0), payloads(0) {}

    inline QResourceRoot(const uchar *t, const uchar *n, const uchar *d) { setSource(t, n, d); }

    virtual ~QResourceRoot() { }

    int findNode(const QString &path, const QLocale &locale=QLocale()) const;

    inline bool isContainer(int node) const { return flags(node) & Directory; }

    inline bool isCompressed(int node) const { return flags(node) & Compressed; }

    const uchar *data(int node, qint64 *size) const;

    QStringList children(int node) const;

    virtual QString mappingRoot() const { return QString(); }

    bool mappingRootSubdir(const QString &path, QString *match=0) const;

    inline bool operator==(const QResourceRoot &other) const

    { return tree == other.tree && names == other.names && payloads == other.payloads; }

    inline bool operator!=(const QResourceRoot &other) const

    { return !operator==(other); }

    enum ResourceRootType { Resource_Builtin, Resource_File, Resource_Buffer };

    virtual ResourceRootType type() const { return Resource_Builtin; }

protected:

    inline void setSource(const uchar *t, const uchar *n, const uchar *d) {

        tree = t;

        names = n;

        payloads = d;

    }

};

Q_DECLARE_TYPEINFO(QResourceRoot, Q_MOVABLE_TYPE);

Q_GLOBAL_STATIC_WITH_ARGS(QMutex, resourceMutex, (QMutex::Recursive))

typedef QList<QResourceRoot*> ResourceList;

Q_GLOBAL_STATIC(ResourceList, resourceList)

Q_GLOBAL_STATIC(QStringList, resourceSearchPaths)

/*!

    \class QResource

    \brief The QResource class provides an interface for reading directly from resources.

    \ingroup io

    \mainclass

    \reentrant

    \since 4.2

    QResource is an object that represents a set of data (and possibly

    children) relating to a single resource entity. QResource gives direct

    access to the bytes in their raw format. In this way direct access

    allows reading data without buffer copying or indirection. Indirection

    is often useful when interacting with the resource entity as if it is a

    file, this can be achieved with QFile. The data and children behind a

    QResource are normally compiled into an application/library, but it is

    also possible to load a resource at runtime. When loaded at run time

    the resource file will be loaded as one big set of data and then given

    out in pieces via references into the resource tree.

    A QResource can either be loaded with an absolute path, either treated

    as a file system rooted with a \c{/} character, or in resource notation

    rooted with a \c{:} character. A relative resource can also be opened

    which will be found through the searchPaths().

    A QResource that is representing a file will have data backing it, this

    data can possibly be compressed, in which case qUncompress() must be

    used to access the real data; this happens implicitly when accessed

    through a QFile. A QResource that is representing a directory will have

    only children and no data.

    \section1 Dynamic Resource Loading

    A resource can be left out of an application's binary and loaded when

    it is needed at run-time by using the registerResource() function. The

    resource file passed into registerResource() must be a binary resource

    as created by rcc. Further information about binary resources can be

    found in \l{The Qt Resource System} documentation.

    This can often be useful when loading a large set of application icons

    that may change based on a setting, or that can be edited by a user and

    later recreated. The resource is immediately loaded into memory, either

    as a result of a single file read operation, or as a memory mapped file.

    This approach can prove to be a significant performance gain as only a

    single file will be loaded, and pieces of data will be given out via the

    path requested in setFileName().

    The unregisterResource() function removes a reference to a particular

    file. If there are QResources that currently reference resources related

    to the unregistered file, they will continue to be valid but the resource

    file itself will be removed from the resource roots, and thus no further

    QResource can be created pointing into this resource data. The resource

    itself will be unmapped from memory when the last QResource that points

    to it is destroyed.

    \sa {The Qt Resource System}, QFile, QDir, QFileInfo

*/

class QResourcePrivate {

public:

    inline QResourcePrivate(QResource *_q) : q_ptr(_q) { clear(); }

    inline ~QResourcePrivate() { clear(); }

    void ensureInitialized() const;

    void ensureChildren() const;

    bool load(const QString &file);

    void clear();

    QLocale locale;

    QString fileName, absoluteFilePath;

    QList<QResourceRoot*> related;

    uint container : 1;

    mutable uint compressed : 1;

    mutable qint64 size;

    mutable const uchar *data;

    mutable QStringList children;

    QResource *q_ptr;

    Q_DECLARE_PUBLIC(QResource)

};

void

QResourcePrivate::clear()

{

    absoluteFilePath.clear();

    compressed = 0;

    data = 0;

    size = 0;

    children.clear();

    container = 0;

    for(int i = 0; i < related.size(); ++i) {

        QResourceRoot *root = related.at(i);

        if(!root->ref.deref())

            delete root;

    }

    related.clear();

}

bool

QResourcePrivate::load(const QString &file)

{

    related.clear();

    QMutexLocker lock(resourceMutex());

    const ResourceList *list = resourceList();

    for(int i = 0; i < list->size(); ++i) {

        QResourceRoot *res = list->at(i);

        const int node = res->findNode(file);

        if(node != -1) {

            if(related.isEmpty()) {

                container = res->isContainer(node);

                if(!container) {

                    data = res->data(node, &size);

                    compressed = res->isCompressed(node);

                } else {

                    data = 0;

                    size = 0;

                    compressed = 0;

                }

            } else if(res->isContainer(node) != container) {

                qWarning("QResourceInfo: Resource [%s] has both data and children!", file.toLatin1().constData());

            }

            res->ref.ref();

            related.append(res);

        } else if(res->mappingRootSubdir(file)) {

            container = true;

            data = 0;

            size = 0;

            compressed = 0;

            res->ref.ref();

            related.append(res);

        }

    }

    return !related.isEmpty();

}

void

QResourcePrivate::ensureInitialized() const

{

    if(!related.isEmpty())

        return;

    QResourcePrivate *that = const_cast<QResourcePrivate *>(this);

    if(fileName == QLatin1String(":"))

        that->fileName += QLatin1Char('/');

    that->absoluteFilePath = fileName;

    if(!that->absoluteFilePath.startsWith(QLatin1Char(':')))

        that->absoluteFilePath.prepend(QLatin1Char(':'));

    QString path = fileName;

    if(path.startsWith(QLatin1Char(':')))

        path = path.mid(1);

    bool found = false;

    if(path.startsWith(QLatin1Char('/'))) {

        found = that->load(path);

    } else {

        QMutexLocker lock(resourceMutex());

        QStringList searchPaths = *resourceSearchPaths();

        searchPaths << QLatin1String("");

        for(int i = 0; i < searchPaths.size(); ++i) {

            const QString searchPath(searchPaths.at(i) + QLatin1Char('/') + path);

            if(that->load(searchPath)) {

                found = true;

                that->absoluteFilePath = QLatin1Char(':') + searchPath;

                break;

            }

        }

    }

}

void

QResourcePrivate::ensureChildren() const

{

    ensureInitialized();

    if(!children.isEmpty() || !container || related.isEmpty())

        return;

    QString path = absoluteFilePath, k;

    if(path.startsWith(QLatin1Char(':')))

        path = path.mid(1);

    QSet<QString> kids;

    for(int i = 0; i < related.size(); ++i) {

        QResourceRoot *res = related.at(i);

        if(res->mappingRootSubdir(path, &k) && !k.isEmpty()) {

            if(!kids.contains(k)) {

                children += k;

                kids.insert(k);

            }

        } else {

            const int node = res->findNode(path);

            if(node != -1) {

                QStringList related_children = res->children(node);

                for(int kid = 0; kid < related_children.size(); ++kid) {

                    k = related_children.at(kid);

                    if(!kids.contains(k)) {

                        children += k;

                        kids.insert(k);

                    }

                }

            }

        }

    }

}

/*!

    Constructs a QResource pointing to \a file. \a locale is used to

    load a specific localization of a resource data.

    \sa QFileInfo, searchPaths(), setFileName(), setLocale()

*/

QResource::QResource(const QString &file, const QLocale &locale) : d_ptr(new QResourcePrivate(this))

{

    Q_D(QResource);

    d->fileName = file;

    d->locale = locale;

}

/*!

    Releases the resources of the QResource object.

*/

QResource::~QResource()

{

    delete d_ptr;

}

/*!

    Sets a QResource to only load the localization of resource to for \a

    locale. If a resource for the specific locale is not found then the

    C locale is used.

    \sa setFileName()

*/

void QResource::setLocale(const QLocale &locale)

{

    Q_D(QResource);

    d->clear();

    d->locale = locale;

}

/*!

    Returns the locale used to locate the data for the QResource.

*/

QLocale QResource::locale() const

{

    Q_D(const QResource);

    return d->locale;

}

/*!

    Sets a QResource to point to \a file. \a file can either be absolute,

    in which case it is opened directly, if relative then the file will be

    tried to be found in searchPaths().

    \sa absoluteFilePath()

*/

void QResource::setFileName(const QString &file)

{

    Q_D(QResource);

    d->clear();

    d->fileName = file;

}

/*!

    Returns the full path to the file that this QResource represents as it

    was passed.

    \sa absoluteFilePath()

*/

QString QResource::fileName() const

{

    Q_D(const QResource);

    d->ensureInitialized();

    return d->fileName;

}

/*!

    Returns the real path that this QResource represents, if the resource

    was found via the searchPaths() it will be indicated in the path.

    \sa fileName()

*/

QString QResource::absoluteFilePath() const

{

    Q_D(const QResource);

    d->ensureInitialized();

    return d->absoluteFilePath;

}

/*!

    Returns true if the resource really exists in the resource hierarchy,

    false otherwise.

*/

bool QResource::isValid() const

{

    Q_D(const QResource);

    d->ensureInitialized();

    return !d->related.isEmpty();

}

/*!

    \fn bool QResource::isFile() const

    Returns true if the resource represents a file and thus has data

    backing it, false if it represents a directory.

    \sa isDir()

*/

/*!

    Returns true if the resource represents a file and the data backing it

    is in a compressed format, false otherwise.

    \sa data(), isFile()

*/

bool QResource::isCompressed() const

{

    Q_D(const QResource);

    d->ensureInitialized();

    return d->compressed;

}

/*!

    Returns the size of the data backing the resource.

    \sa data(), isFile()

*/

qint64 QResource::size() const

{

    Q_D(const QResource);

    d->ensureInitialized();

    return d->size;

}

/*!

    Returns direct access to a read only segment of data that this resource

    represents. If the resource is compressed the data returns is

    compressed and qUncompress() must be used to access the data. If the

    resource is a directory 0 is returned.

    \sa size(), isCompressed(), isFile()

*/

const uchar *QResource::data() const

{

    Q_D(const QResource);

    d->ensureInitialized();

    return d->data;

}

/*!

    Returns true if the resource represents a directory and thus may have

    children() in it, false if it represents a file.

    \sa isFile()

*/

bool QResource::isDir() const

{

    Q_D(const QResource);

    d->ensureInitialized();

    return d->container;

}

/*!

    Returns a list of all resources in this directory, if the resource

    represents a file the list will be empty.

    \sa isDir()

*/

QStringList QResource::children() const

{

    Q_D(const QResource);

    d->ensureChildren();

    return d->children;

}

/*!

  \obsolete

  Adds \a path to the search paths searched in to find resources that are

  not specified with an absolute path. The \a path must be an absolute

  path (start with \c{/}).

  The default search path is to search only in the root (\c{:/}). The last

  path added will be consulted first upon next QResource creation.

  Use QDir::addSearchPath() with a prefix instead.

*/

void

QResource::addSearchPath(const QString &path)

{

    if (!path.startsWith(QLatin1Char('/'))) {

        qWarning("QResource::addResourceSearchPath: Search paths must be absolute (start with /) [%s]",

                 path.toLocal8Bit().data());

        return;

    }

    QMutexLocker lock(resourceMutex());

    resourceSearchPaths()->prepend(path);

}

/*!

  Returns the current search path list. This list is consulted when

  creating a relative resource.

  \sa addSearchPath()

*/

QStringList

QResource::searchPaths()

{

    QMutexLocker lock(resourceMutex());

    return *resourceSearchPaths();

}

inline int QResourceRoot::hash(int node) const

{

    if(!node) //root

        return 0;

    const int offset = findOffset(node);

    int name_offset = (tree[offset+0] << 24) + (tree[offset+1] << 16) +

                      (tree[offset+2] << 8) + (tree[offset+3] << 0);

    name_offset += 2; //jump past name length

    return (names[name_offset+0] << 24) + (names[name_offset+1] << 16) +

           (names[name_offset+2] << 8) + (names[name_offset+3] << 0);

}

inline QString QResourceRoot::name(int node) const

{

    if(!node) // root

        return QString();

    const int offset = findOffset(node);

    QString ret;

    int name_offset = (tree[offset+0] << 24) + (tree[offset+1] << 16) +

                      (tree[offset+2] << 8) + (tree[offset+3] << 0);

    const short name_length = (names[name_offset+0] << 8) +

                              (names[name_offset+1] << 0);

    name_offset += 2;

    name_offset += 4; //jump past hash

    for(int i = 0; i < name_length*2; i+=2)

        ret += QChar(names[name_offset+i+1], names[name_offset+i]);

    return ret;

}

int QResourceRoot::findNode(const QString &_path, const QLocale &locale) const

{

    QString path = QDir::cleanPath(_path);

    // QDir::cleanPath does not remove two trailing slashes under _Windows_

    // due to support for UNC paths. Remove those manually.

    if (path.startsWith(QLatin1String("//")))

        path.remove(0, 1);

    {

        QString root = mappingRoot();

        if(!root.isEmpty()) {

            if(root == path) {

                path = QLatin1String("/");

            } else {

                if(!root.endsWith(QLatin1String("/")))

                    root += QLatin1String("/");

                if(path.size() >= root.size() && path.startsWith(root))

                    path = path.mid(root.length()-1);

                if(path.isEmpty())

                    path = QLatin1String("/");

            }

        }

    }

#ifdef DEBUG_RESOURCE_MATCH

    qDebug() << "!!!!" << "START" << path << locale.country() << locale.language();

#endif

    if(path == QLatin1String("/"))

        return 0;

    //the root node is always first

    int child_count = (tree[6] << 24) + (tree[7] << 16) +

                      (tree[8] << 8) + (tree[9] << 0);

    int child       = (tree[10] << 24) + (tree[11] << 16) +

                      (tree[12] << 8) + (tree[13] << 0);

    //now iterate up the tree

    int node = -1;

    QStringList segments = path.split(QLatin1Char('/'), QString::SkipEmptyParts);

#ifdef DEBUG_RESOURCE_MATCH

    qDebug() << "****" << segments;

#endif

    for(int i = 0; child_count && i < segments.size(); ++i) {

        const QString &segment = segments[i];

#ifdef DEBUG_RESOURCE_MATCH

        qDebug() << "  CHILDREN" << segment;

        for(int j = 0; j < child_count; ++j) {

            qDebug() << "   " << child+j << " :: " << name(child+j);

        }

#endif

        const int h = qHash(segment);

        //do the binary search for the hash

        int l = 0, r = child_count-1;

        int sub_node = (l+r+1)/2;

        while(r != l) {

            const int sub_node_hash = hash(child+sub_node);

            if(h == sub_node_hash)

                break;

            else if(h < sub_node_hash)

                r = sub_node - 1;

            else

                l = sub_node;

            sub_node = (l + r + 1) / 2;

        }

        sub_node += child;

        //now do the "harder" compares

        bool found = false;

        if(hash(sub_node) == h) {

            while(sub_node > child && hash(sub_node-1) == h) //backup for collisions

                --sub_node;

            for(; sub_node < child+child_count && hash(sub_node) == h; ++sub_node) { //here we go...

                if(name(sub_node) == segment) {

                    found = true;

                    int offset = findOffset(sub_node);

#ifdef DEBUG_RESOURCE_MATCH

                    qDebug() << "  TRY" << sub_node << name(sub_node) << offset;

#endif

                    offset += 4;  //jump past name

                    const short flags = (tree[offset+0] << 8) +

                                        (tree[offset+1] << 0);

                    offset += 2;

                    if(i == segments.size()-1) {

                        if(!(flags & Directory)) {

                            const short country = (tree[offset+0] << 8) +

                                                  (tree[offset+1] << 0);

                            offset += 2;

                            const short language = (tree[offset+0] << 8) +

                                                   (tree[offset+1] << 0);

                            offset += 2;

#ifdef DEBUG_RESOURCE_MATCH

                            qDebug() << "    " << "LOCALE" << country << language;

#endif

                            if(country == locale.country() && language == locale.language()) {

#ifdef DEBUG_RESOURCE_MATCH

                                qDebug() << "!!!!" << "FINISHED" << __LINE__ << sub_node;

#endif

                                return sub_node;

                            } else if((country == QLocale::AnyCountry && language == locale.language()) ||

                                      (country == QLocale::AnyCountry && language == QLocale::C && node == -1)) {

                                node = sub_node;

                            }

                            continue;

                        } else {

#ifdef DEBUG_RESOURCE_MATCH

                            qDebug() << "!!!!" << "FINISHED" << __LINE__ << sub_node;

#endif

                            return sub_node;

                        }

                    }

                    if(!(flags & Directory))

                        return -1;

                    child_count = (tree[offset+0] << 24) + (tree[offset+1] << 16) +

                                  (tree[offset+2] << 8) + (tree[offset+3] << 0);

                    offset += 4;

                    child = (tree[offset+0] << 24) + (tree[offset+1] << 16) +

                            (tree[offset+2] << 8) + (tree[offset+3] << 0);

                    break;

                }

            }

        }

        if(!found)

            break;

    }

#ifdef DEBUG_RESOURCE_MATCH

    qDebug() << "!!!!" << "FINISHED" << __LINE__ << node;

#endif

    return node;

}

short QResourceRoot::flags(int node) const

{

    if(node == -1)

        return 0;

    const int offset = findOffset(node) + 4; //jump past name

    return (tree[offset+0] << 8) + (tree[offset+1] << 0);

}

const uchar *QResourceRoot::data(int node, qint64 *size) const

{

    if(node == -1) {

        *size = 0;

        return 0;

    }

    int offset = findOffset(node) + 4; //jump past name

    const short flags = (tree[offset+0] << 8) + (tree[offset+1] << 0);

    offset += 2;

    offset += 4; //jump past locale

    if(!(flags & Directory)) {

        const int data_offset = (tree[offset+0] << 24) + (tree[offset+1] << 16) +

                                (tree[offset+2] << 8) + (tree[offset+3] << 0);

        const uint data_length = (payloads[data_offset+0] << 24) + (payloads[data_offset+1] << 16) +

                                 (payloads[data_offset+2] << 8) + (payloads[data_offset+3] << 0);

        const uchar *ret = payloads+data_offset+4;

        *size = data_length;

        return ret;

    }

    *size = 0;

    return 0;

}

QStringList QResourceRoot::children(int node) const

{

    if(node == -1)

        return QStringList();

    int offset = findOffset(node) + 4; //jump past name

    const short flags = (tree[offset+0] << 8) + (tree[offset+1] << 0);

    offset += 2;

    QStringList ret;

    if(flags & Directory) {

        const int child_count = (tree[offset+0] << 24) + (tree[offset+1] << 16) +

                                (tree[offset+2] << 8) + (tree[offset+3] << 0);

        offset += 4;

        const int child_off = (tree[offset+0] << 24) + (tree[offset+1] << 16) +

                              (tree[offset+2] << 8) + (tree[offset+3] << 0);

        for(int i = child_off; i < child_off+child_count; ++i)

            ret << name(i);

    }

    return ret;

}

bool QResourceRoot::mappingRootSubdir(const QString &path, QString *match) const

{

    const QString root = mappingRoot();

    if(!root.isEmpty()) {

        const QStringList root_segments = root.split(QLatin1Char('/'), QString::SkipEmptyParts),

                          path_segments = path.split(QLatin1Char('/'), QString::SkipEmptyParts);

        if(path_segments.size() <= root_segments.size()) {

            int matched = 0;

            for(int i = 0; i < path_segments.size(); ++i) {

                if(root_segments[i] != path_segments[i])

                    break;

                ++matched;

            }

            if(matched == path_segments.size()) {

                if(match && root_segments.size() > matched)

                    *match = root_segments.at(matched);

                return true;

            }

        }

    }

    return false;

}

Q_CORE_EXPORT bool qRegisterResourceData(int version, const unsigned char *tree,

                                         const unsigned char *name, const unsigned char *data)

{

    QMutexLocker lock(resourceMutex());

    if(version == 0x01 && resourceList()) {

        bool found = false;

        QResourceRoot res(tree, name, data);

        for(int i = 0; i < resourceList()->size(); ++i) {

            if(*resourceList()->at(i) == res) {

                found = true;

                break;

            }

        }

        if(!found) {

            QResourceRoot *root = new QResourceRoot(tree, name, data);

            root->ref.ref();

            resourceList()->append(root);

        }

        return true;

    }

    return false;

}

Q_CORE_EXPORT bool qUnregisterResourceData(int version, const unsigned char *tree,

                                           const unsigned char *name, const unsigned char *data)

{

    QMutexLocker lock(resourceMutex());

    if(version == 0x01 && resourceList()) {

        QResourceRoot res(tree, name, data);

        for(int i = 0; i < resourceList()->size(); ) {

            if(*resourceList()->at(i) == res) {

                QResourceRoot *root = resourceList()->takeAt(i);

                if(!root->ref.deref())

                    delete root;

            } else {

                ++i;

            }

        }

        return true;

    }

    return false;

}

//run time resource creation

class QDynamicBufferResourceRoot: public QResourceRoot

{

    QString root;

    const uchar *buffer;

public:

    inline QDynamicBufferResourceRoot(const QString &_root) : root(_root), buffer(0) { }

    inline ~QDynamicBufferResourceRoot() { }

    inline const uchar *mappingBuffer() const { return buffer; }

    virtual QString mappingRoot() const { return root; }

    virtual ResourceRootType type() const { return Resource_Buffer; }

    bool registerSelf(const uchar *b) {

        //setup the data now

        int offset = 0;

        //magic number

        if(b[offset+0] != 'q' || b[offset+1] != 'r' ||

           b[offset+2] != 'e' || b[offset+3] != 's') {

            return false;

        }

        offset += 4;

        const int version = (b[offset+0] << 24) + (b[offset+1] << 16) +

                         (b[offset+2] << 8) + (b[offset+3] << 0);

        offset += 4;

        const int tree_offset = (b[offset+0] << 24) + (b[offset+1] << 16) +

                                (b[offset+2] << 8) + (b[offset+3] << 0);

        offset += 4;

        const int data_offset = (b[offset+0] << 24) + (b[offset+1] << 16) +

                                (b[offset+2] << 8) + (b[offset+3] << 0);

        offset += 4;

        const int name_offset = (b[offset+0] << 24) + (b[offset+1] << 16) +

                                (b[offset+2] << 8) + (b[offset+3] << 0);

        offset += 4;

        if(version == 0x01) {

            buffer = b;

            setSource(b+tree_offset, b+name_offset, b+data_offset);

            return true;

        }

        return false;

    }

};

#if defined(Q_OS_UNIX)

#define QT_USE_MMAP

#endif

// most of the headers below are already included in qplatformdefs.h

// also this lacks Large File support but that's probably irrelevant

#if defined(QT_USE_MMAP)

// for mmap

QT_BEGIN_INCLUDE_NAMESPACE

#include <sys/mman.h>

#include <errno.h>

QT_END_INCLUDE_NAMESPACE

#endif

class QDynamicFileResourceRoot: public QDynamicBufferResourceRoot

{

    QString fileName;

    // for mmap'ed files, this is what needs to be unmapped.

    uchar *unmapPointer;

    unsigned int unmapLength;

public:

    inline QDynamicFileResourceRoot(const QString &_root) : QDynamicBufferResourceRoot(_root), unmapPointer(0), unmapLength(0) { }

    ~QDynamicFileResourceRoot() {

#if defined(QT_USE_MMAP)

        if (unmapPointer) {

            munmap((char*)unmapPointer, unmapLength);

            unmapPointer = 0;

            unmapLength = 0;

        } else

#endif

        {

            delete [] (uchar *)mappingBuffer();

        }

    }

    QString mappingFile() const { return fileName; }

    virtual ResourceRootType type() const { return Resource_File; }

    bool registerSelf(const QString &f) {

        bool fromMM = false;

        uchar *data = 0;

        unsigned int data_len = 0;

#ifdef QT_USE_MMAP

#ifndef MAP_FILE

#define MAP_FILE 0

#endif

#ifndef MAP_FAILED

#define MAP_FAILED -1

#endif

        int fd = QT_OPEN(QFile::encodeName(f), O_RDONLY,

#if defined(Q_OS_WIN)

                         _S_IREAD | _S_IWRITE

#else

                         0666

#endif

            );

        if (fd >= 0) {

            QT_STATBUF st;

            if (!QT_FSTAT(fd, &st)) {

                uchar *ptr;

                ptr = reinterpret_cast<uchar *>(

                    mmap(0, st.st_size,             // any address, whole file

                         PROT_READ,                 // read-only memory

                         MAP_FILE | MAP_PRIVATE,    // swap-backed map from file

                         fd, 0));                   // from offset 0 of fd

                if (ptr && ptr != reinterpret_cast<uchar *>(MAP_FAILED)) {

                    data = ptr;

                    data_len = st.st_size;

                    fromMM = true;

                }

            }

            ::close(fd);

        }

#endif // QT_USE_MMAP

        if(!data) {

            QFile file(f);

            if (!file.exists())

                return false;

            data_len = file.size();

            data = new uchar[data_len];

            bool ok = false;

            if (file.open(QIODevice::ReadOnly))

                ok = (data_len == (uint)file.read((char*)data, data_len));

            if (!ok) {

                delete [] data;

                data = 0;

                data_len = 0;

                return false;

            }

            fromMM = false;

        }

        if(data && QDynamicBufferResourceRoot::registerSelf(data)) {

            if(fromMM) {

                unmapPointer = data;

                unmapLength = data_len;

            }

            fileName = f;

            return true;

        }

        return false;

    }

};

static QString qt_resource_fixResourceRoot(QString r) {

    if(!r.isEmpty()) {

        if(r.startsWith(QLatin1Char(':')))

            r = r.mid(1);

        if(!r.isEmpty())

            r = QDir::cleanPath(r);

    }

    return r;

}

/*!

   \fn bool QResource::registerResource(const QString &rccFileName, const QString &mapRoot)

   Registers the resource with the given \a rccFileName at the location in the

   resource tree specified by \a mapRoot, and returns true if the file is

   successfully opened; otherwise returns false.

   \sa unregisterResource()

*/

bool

QResource::registerResource(const QString &rccFilename, const QString &resourceRoot)

{

    QString r = qt_resource_fixResourceRoot(resourceRoot);

    if(!r.isEmpty() && r[0] != QLatin1Char('/')) {

        qWarning("QDir::registerResource: Registering a resource [%s] must be rooted in an absolute path (start with /) [%s]",

                 rccFilename.toLocal8Bit().data(), resourceRoot.toLocal8Bit().data());

        return false;

    }

    QDynamicFileResourceRoot *root = new QDynamicFileResourceRoot(r);

    if(root->registerSelf(rccFilename)) {

        root->ref.ref();

        QMutexLocker lock(resourceMutex());

        resourceList()->append(root);

        return true;

    }

    delete root;

    return false;

}

/*!

  \fn bool QResource::unregisterResource(const QString &rccFileName, const QString &mapRoot)

  Unregisters the resource with the given \a rccFileName at the location in

  the resource tree specified by \a mapRoot, and returns true if the

  resource is successfully unloaded and no references exist for the

  resource; otherwise returns false.

  \sa registerResource()

*/

bool

QResource::unregisterResource(const QString &rccFilename, const QString &resourceRoot)

{

    QString r = qt_resource_fixResourceRoot(resourceRoot);

    QMutexLocker lock(resourceMutex());

    ResourceList *list = resourceList();

    for(int i = 0; i < list->size(); ++i) {

        QResourceRoot *res = list->at(i);

        if(res->type() == QResourceRoot::Resource_File) {

	    QDynamicFileResourceRoot *root = reinterpret_cast<QDynamicFileResourceRoot*>(res);

	    if(root->mappingFile() == rccFilename && root->mappingRoot() == r) {

                resourceList()->removeAt(i);

                if(!root->ref.deref()) {

                    delete root;

                    return true;

                }

                return false;

            }

	}

    }

    return false;

}

/*!

   \fn bool QResource::registerResource(const uchar *rccData, const QString &mapRoot)

   \since 4.3

   Registers the resource with the given \a rccData at the location in the

   resource tree specified by \a mapRoot, and returns true if the file is

   successfully opened; otherwise returns false.

   \warning The data must remain valid throughout the life of any QFile

   that may reference the resource data.

   \sa unregisterResource()

*/

bool

QResource::registerResource(const uchar *rccData, const QString &resourceRoot)

{

    QString r = qt_resource_fixResourceRoot(resourceRoot);

    if(!r.isEmpty() && r[0] != QLatin1Char('/')) {

        qWarning("QDir::registerResource: Registering a resource [%p] must be rooted in an absolute path (start with /) [%s]",

                 rccData, resourceRoot.toLocal8Bit().data());

        return false;

    }

    QDynamicBufferResourceRoot *root = new QDynamicBufferResourceRoot(r);

    if(root->registerSelf(rccData)) {

        root->ref.ref();

        QMutexLocker lock(resourceMutex());

        resourceList()->append(root);

        return true;

    }

    delete root;

    return false;

}

/*!

  \fn bool QResource::unregisterResource(const uchar *rccData, const QString &mapRoot)

  \since 4.3

  Unregisters the resource with the given \a rccData at the location in the

  resource tree specified by \a mapRoot, and returns true if the resource is

  successfully unloaded and no references exist into the resource; otherwise returns false.

  \sa registerResource()

*/

bool

QResource::unregisterResource(const uchar *rccData, const QString &resourceRoot)

{

    QString r = qt_resource_fixResourceRoot(resourceRoot);

    QMutexLocker lock(resourceMutex());

    ResourceList *list = resourceList();

    for(int i = 0; i < list->size(); ++i) {

        QResourceRoot *res = list->at(i);

        if(res->type() == QResourceRoot::Resource_Buffer) {

	    QDynamicBufferResourceRoot *root = reinterpret_cast<QDynamicBufferResourceRoot*>(res);

	    if(root->mappingBuffer() == rccData && root->mappingRoot() == r) {

                resourceList()->removeAt(i);

                if(!root->ref.deref()) {

                    delete root;

                    return true;

                }

		return false;

            }

	}

    }

    return false;

}

//file type handler

class QResourceFileEngineHandler : public QAbstractFileEngineHandler

{

public:

    QResourceFileEngineHandler() { }

    ~QResourceFileEngineHandler() { }

    QAbstractFileEngine *create(const QString &path) const;

};

QAbstractFileEngine *QResourceFileEngineHandler::create(const QString &path) const

{

    if (path.size() > 0 && path.startsWith(QLatin1Char(':')))

        return new QResourceFileEngine(path);

    return 0;

}

//resource engine

class QResourceFileEnginePrivate : public QAbstractFileEnginePrivate

{

protected:

    Q_DECLARE_PUBLIC(QResourceFileEngine)

private:

    uchar *map(qint64 offset, qint64 size, QFile::MemoryMapFlags flags);

    bool unmap(uchar *ptr);

    qint64 offset;

    QResource resource;

    QByteArray uncompressed;

protected:

    QResourceFileEnginePrivate() : offset(0) { }

};

bool QResourceFileEngine::mkdir(const QString &, bool) const

{

    return false;

}

bool QResourceFileEngine::rmdir(const QString &, bool) const

{

    return false;

}

bool QResourceFileEngine::setSize(qint64)

{

    return false;

}

QStringList QResourceFileEngine::entryList(QDir::Filters filters, const QStringList &filterNames) const

{

    return QAbstractFileEngine::entryList(filters, filterNames);

}

bool QResourceFileEngine::caseSensitive() const

{

    return true;

}

QResourceFileEngine::QResourceFileEngine(const QString &file) :

    QAbstractFileEngine(*new QResourceFileEnginePrivate)

{

    Q_D(QResourceFileEngine);

    d->resource.setFileName(file);

    if(d->resource.isCompressed() && d->resource.size()) {

#ifndef QT_NO_COMPRESS

        d->uncompressed = qUncompress(d->resource.data(), d->resource.size());

#else

        Q_ASSERT(!"QResourceFileEngine::open: Qt built without support for compression");

#endif

    }

}

QResourceFileEngine::~QResourceFileEngine()

{

}

void QResourceFileEngine::setFileName(const QString &file)

{

    Q_D(QResourceFileEngine);

    d->resource.setFileName(file);

}

bool QResourceFileEngine::open(QIODevice::OpenMode flags)

{

    Q_D(QResourceFileEngine);

    if (d->resource.fileName().isEmpty()) {

        qWarning("QResourceFileEngine::open: Missing file name");

        return false;

    }

    if(flags & QIODevice::WriteOnly)

        return false;

    if(!d->resource.isValid())

       return false;

    return true;

}

bool QResourceFileEngine::close()

{

    Q_D(QResourceFileEngine);

    d->offset = 0;

    d->uncompressed.clear();

    return true;

}

bool QResourceFileEngine::flush()

{

    return false;

}

qint64 QResourceFileEngine::read(char *data, qint64 len)

{

    Q_D(QResourceFileEngine);

    if(len > size()-d->offset)

        len = size()-d->offset;

    if(len <= 0)

        return 0;

    if(d->resource.isCompressed())

        memcpy(data, d->uncompressed.constData()+d->offset, len);

    else

        memcpy(data, d->resource.data()+d->offset, len);

    d->offset += len;

    return len;

}

qint64 QResourceFileEngine::write(const char *, qint64)

{

    return -1;

}

bool QResourceFileEngine::remove()

{

    return false;

}

bool QResourceFileEngine::copy(const QString &)

{

    return false;

}

bool QResourceFileEngine::rename(const QString &)

{

    return false;

}

bool QResourceFileEngine::link(const QString &)

{

    return false;

}

qint64 QResourceFileEngine::size() const

{

    Q_D(const QResourceFileEngine);

    if(!d->resource.isValid())

        return 0;

    if(d->resource.isCompressed())

        return d->uncompressed.size();

    return d->resource.size();

}

qint64 QResourceFileEngine::pos() const

{

    Q_D(const QResourceFileEngine);

    return d->offset;

}

bool QResourceFileEngine::atEnd() const

{

    Q_D(const QResourceFileEngine);

    if(!d->resource.isValid())

        return true;

    return d->offset == size();

}

bool QResourceFileEngine::seek(qint64 pos)

{

    Q_D(QResourceFileEngine);

    if(!d->resource.isValid())

        return false;

    if(d->offset > size())

        return false;

    d->offset = pos;

    return true;

}

bool QResourceFileEngine::isSequential() const

{

    return false;

}

QAbstractFileEngine::FileFlags QResourceFileEngine::fileFlags(QAbstractFileEngine::FileFlags type) const

{

    Q_D(const QResourceFileEngine);

    QAbstractFileEngine::FileFlags ret = 0;

    if(!d->resource.isValid())

        return ret;

    if(type & PermsMask)

        ret |= QAbstractFileEngine::FileFlags(ReadOwnerPerm|ReadUserPerm|ReadGroupPerm|ReadOtherPerm);

    if(type & TypesMask) {

        if(d->resource.isDir())

            ret |= DirectoryType;

        else

            ret |= FileType;

    }

    if(type & FlagsMask) {

        ret |= ExistsFlag;

        if(d->resource.absoluteFilePath() == QLatin1String(":/"))

            ret |= RootFlag;

    }

    return ret;

}

bool QResourceFileEngine::setPermissions(uint)

{

    return false;

}

QString QResourceFileEngine::fileName(FileName file) const

{

    Q_D(const QResourceFileEngine);

    if(file == BaseName) {

	int slash = d->resource.fileName().lastIndexOf(QLatin1Char('/'));

	if (slash == -1)

	    return d->resource.fileName();

	return d->resource.fileName().mid(slash + 1);

    } else if(file == PathName || file == AbsolutePathName) {

        const QString path = (file == AbsolutePathName) ? d->resource.absoluteFilePath() : d->resource.fileName();

	const int slash = path.lastIndexOf(QLatin1Char('/'));

	if (slash != -1)

	    return path.left(slash);

    } else if(file == CanonicalName || file == CanonicalPathName) {

        const QString absoluteFilePath = d->resource.absoluteFilePath();

        if(file == CanonicalPathName) {

            const int slash = absoluteFilePath.lastIndexOf(QLatin1Char('/'));

            if (slash != -1)

                return absoluteFilePath.left(slash);

        }

        return absoluteFilePath;

    }

    return d->resource.fileName();

}

bool QResourceFileEngine::isRelativePath() const

{

    return false;

}

uint QResourceFileEngine::ownerId(FileOwner) const

{

    static const uint nobodyID = (uint) -2;

    return nobodyID;

}

QString QResourceFileEngine::owner(FileOwner) const

{

    return QString();

}

QDateTime QResourceFileEngine::fileTime(FileTime) const

{

    return QDateTime();

}

/*!

    \internal

*/

QAbstractFileEngine::Iterator *QResourceFileEngine::beginEntryList(QDir::Filters filters,

                                                                   const QStringList &filterNames)

{

    return new QResourceFileEngineIterator(filters, filterNames);

}

/*!

    \internal

*/

QAbstractFileEngine::Iterator *QResourceFileEngine::endEntryList()

{

    return 0;

}

bool QResourceFileEngine::extension(Extension extension, const ExtensionOption *option, ExtensionReturn *output)

{

    Q_D(QResourceFileEngine);

    if (extension == MapExtension) {

        const MapExtensionOption *options = (MapExtensionOption*)(option);

        MapExtensionReturn *returnValue = static_cast<MapExtensionReturn*>(output);

        returnValue->address = d->map(options->offset, options->size, options->flags);

        return (returnValue->address != 0);

    }

    if (extension == UnMapExtension) {

        UnMapExtensionOption *options = (UnMapExtensionOption*)option;

        return d->unmap(options->address);

    }

    return false;

}

bool QResourceFileEngine::supportsExtension(Extension extension) const

{

    return (extension == UnMapExtension || extension == MapExtension);

}

uchar *QResourceFileEnginePrivate::map(qint64 offset, qint64 size, QFile::MemoryMapFlags flags)

{

    Q_Q(QResourceFileEngine);

    Q_UNUSED(flags);

    if (!resource.isValid()

        || offset < 0

        || size < 0

        || offset + size > resource.size()

        || (size == 0)) {

        q->setError(QFile::UnspecifiedError, QString());

        return 0;

    }

    uchar *address = const_cast<uchar *>(resource.data());

    return (address + offset);

}

bool QResourceFileEnginePrivate::unmap(uchar *ptr)

{

    Q_UNUSED(ptr);

    return true;

}

//Initialization and cleanup

Q_GLOBAL_STATIC(QResourceFileEngineHandler, resource_file_handler)

static int qt_force_resource_init() { resource_file_handler(); return 1; }

Q_CORE_EXPORT void qInitResourceIO() { resource_file_handler(); }

static int qt_forced_resource_init = qt_force_resource_init();

Q_CONSTRUCTOR_FUNCTION(qt_force_resource_init)

QT_END_NAMESPACE