path: root/src/libs/utils/mimetypes/mimeprovider.cpp

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#include "mimeprovider_p.h"

#include "mimetypeparser_p.h"
#include <qstandardpaths.h>
#include "mimemagicrulematcher_p.h"

#include <QXmlStreamReader>
#include <QDir>
#include <QFile>
#include <QByteArrayMatcher>
#include <QDebug>
#include <QDateTime>
#include <QtEndian>
#include <QtGlobal>

using namespace Utils;
using namespace Utils::Internal;

static QString fallbackParent(const QString &mimeTypeName)
{
    const QString myGroup = mimeTypeName.left(mimeTypeName.indexOf(QLatin1Char('/')));
    // All text/* types are subclasses of text/plain.
    if (myGroup == QLatin1String("text") && mimeTypeName != QLatin1String("text/plain"))
        return QLatin1String("text/plain");
    // All real-file mimetypes implicitly derive from application/octet-stream
    if (myGroup != QLatin1String("inode") &&
        // ignore non-file extensions
        myGroup != QLatin1String("all") && myGroup != QLatin1String("fonts") && myGroup != QLatin1String("print") && myGroup != QLatin1String("uri")
        && mimeTypeName != QLatin1String("application/octet-stream")) {
        return QLatin1String("application/octet-stream");
    }
    return QString();
}

MimeProviderBase::MimeProviderBase(MimeDatabasePrivate *db)
    : m_db(db)
{
}

static int mime_secondsBetweenChecks = 5;

bool MimeProviderBase::shouldCheck()
{
    const QDateTime now = QDateTime::currentDateTime();
    if (m_lastCheck.isValid() && m_lastCheck.secsTo(now) < mime_secondsBetweenChecks)
        return false;
    m_lastCheck = now;
    return true;
}

//MimeBinaryProvider::MimeBinaryProvider(MimeDatabasePrivate *db)
//    : MimeProviderBase(db), m_mimetypeListLoaded(false)
//{
//}

//#if defined(Q_OS_UNIX) && !defined(Q_OS_INTEGRITY)
//#define QT_USE_MMAP
//#endif

//struct MimeBinaryProvider::CacheFile
//{
//    CacheFile(const QString &fileName);
//    ~CacheFile();

//    bool isValid() const { return m_valid; }
//    inline quint16 getUint16(int offset) const
//    {
//        return qFromBigEndian(*reinterpret_cast<quint16 *>(data + offset));
//    }
//    inline quint32 getUint32(int offset) const
//    {
//        return qFromBigEndian(*reinterpret_cast<quint32 *>(data + offset));
//    }
//    inline const char *getCharStar(int offset) const
//    {
//        return reinterpret_cast<const char *>(data + offset);
//    }
//    bool load();
//    bool reload();

//    QFile file;
//    uchar *data;
//    QDateTime m_mtime;
//    bool m_valid;
//};

//MimeBinaryProvider::CacheFile::CacheFile(const QString &fileName)
//    : file(fileName), m_valid(false)
//{
//    load();
//}

//MimeBinaryProvider::CacheFile::~CacheFile()
//{
//}

//bool MimeBinaryProvider::CacheFile::load()
//{
//    if (!file.open(QIODevice::ReadOnly))
//        return false;
//    data = file.map(0, file.size());
//    if (data) {
//        const int major = getUint16(0);
//        const int minor = getUint16(2);
//        m_valid = (major == 1 && minor >= 1 && minor <= 2);
//    }
//    m_mtime = QFileInfo(file).lastModified();
//    return m_valid;
//}

//bool MimeBinaryProvider::CacheFile::reload()
//{
//    //qDebug() << "reload!" << file->fileName();
//    m_valid = false;
//    if (file.isOpen()) {
//        file.close();
//    }
//    data = 0;
//    return load();
//}

//MimeBinaryProvider::CacheFile *MimeBinaryProvider::CacheFileList::findCacheFile(const QString &fileName) const
//{
//    for (const_iterator it = begin(); it != end(); ++it) {
//        if ((*it)->file.fileName() == fileName)
//            return *it;
//    }
//    return 0;
//}

//MimeBinaryProvider::~MimeBinaryProvider()
//{
//    qDeleteAll(m_cacheFiles);
//}

//// Position of the "list offsets" values, at the beginning of the mime.cache file
//enum {
//    PosAliasListOffset = 4,
//    PosParentListOffset = 8,
//    PosLiteralListOffset = 12,
//    PosReverseSuffixTreeOffset = 16,
//    PosGlobListOffset = 20,
//    PosMagicListOffset = 24,
//    // PosNamespaceListOffset = 28,
//    PosIconsListOffset = 32,
//    PosGenericIconsListOffset = 36
//};

//bool MimeBinaryProvider::isValid()
//{
//#if defined(QT_USE_MMAP)
//    if (!qEnvironmentVariableIsEmpty("QT_NO_MIME_CACHE"))
//        return false;

//    Q_ASSERT(m_cacheFiles.isEmpty()); // this method is only ever called once
//    checkCache();

//    if (m_cacheFiles.count() > 1)
//        return true;
//    if (m_cacheFiles.isEmpty())
//        return false;

//    // We found exactly one file; is it the user-modified mimes, or a system file?
//    const QString foundFile = m_cacheFiles.first()->file.fileName();
//    const QString localCacheFile = QStandardPaths::writableLocation(QStandardPaths::GenericDataLocation) + QLatin1String("/mime/mime.cache");

//    return foundFile != localCacheFile;
//#else
//    return false;
//#endif
//}

//bool MimeBinaryProvider::CacheFileList::checkCacheChanged()
//{
//    bool somethingChanged = false;
//    QMutableListIterator<CacheFile *> it(*this);
//    while (it.hasNext()) {
//        CacheFile *cacheFile = it.next();
//        QFileInfo fileInfo(cacheFile->file);
//        if (!fileInfo.exists()) { // This can't happen by just running update-mime-database. But the user could use rm -rf :-)
//            delete cacheFile;
//            it.remove();
//            somethingChanged = true;
//        } else if (fileInfo.lastModified() > cacheFile->m_mtime) {
//            if (!cacheFile->reload()) {
//                delete cacheFile;
//                it.remove();
//            }
//            somethingChanged = true;
//        }
//    }
//    return somethingChanged;
//}

//void MimeBinaryProvider::checkCache()
//{
//    if (!shouldCheck())
//        return;

//    // First iterate over existing known cache files and check for uptodate
//    if (m_cacheFiles.checkCacheChanged())
//        m_mimetypeListLoaded = false;

//    // Then check if new cache files appeared
//    const QStringList cacheFileNames = QStandardPaths::locateAll(QStandardPaths::GenericDataLocation, QLatin1String("mime/mime.cache"));
//    if (cacheFileNames != m_cacheFileNames) {
//        foreach (const QString &cacheFileName, cacheFileNames) {
//            CacheFile *cacheFile = m_cacheFiles.findCacheFile(cacheFileName);
//            if (!cacheFile) {
//                //qDebug() << "new file:" << cacheFileName;
//                cacheFile = new CacheFile(cacheFileName);
//                if (cacheFile->isValid()) // verify version
//                    m_cacheFiles.append(cacheFile);
//                else
//                    delete cacheFile;
//            }
//        }
//        m_cacheFileNames = cacheFileNames;
//        m_mimetypeListLoaded = false;
//    }
//}

//static MimeType mimeTypeForNameUnchecked(const QString &name)
//{
//    MimeTypePrivate data;
//    data.name = name;
//    // The rest is retrieved on demand.
//    // comment and globPatterns: in loadMimeTypePrivate
//    // iconName: in loadIcon
//    // genericIconName: in loadGenericIcon
//    return MimeType(data);
//}

//MimeType MimeBinaryProvider::mimeTypeForName(const QString &name)
//{
//    checkCache();
//    if (!m_mimetypeListLoaded)
//        loadMimeTypeList();
//    if (!m_mimetypeNames.contains(name))
//        return MimeType(); // unknown mimetype
//    return mimeTypeForNameUnchecked(name);
//}

//QStringList MimeBinaryProvider::findByFileName(const QString &fileName, QString *foundSuffix)
//{
//    checkCache();
//    if (fileName.isEmpty())
//        return QStringList();
//    const QString lowerFileName = fileName.toLower();
//    MimeGlobMatchResult result;
//    // TODO this parses in the order (local, global). Check that it handles "NOGLOBS" correctly.
//    foreach (CacheFile *cacheFile, m_cacheFiles) {
//        matchGlobList(result, cacheFile, cacheFile->getUint32(PosLiteralListOffset), fileName);
//        matchGlobList(result, cacheFile, cacheFile->getUint32(PosGlobListOffset), fileName);
//        const int reverseSuffixTreeOffset = cacheFile->getUint32(PosReverseSuffixTreeOffset);
//        const int numRoots = cacheFile->getUint32(reverseSuffixTreeOffset);
//        const int firstRootOffset = cacheFile->getUint32(reverseSuffixTreeOffset + 4);
//        matchSuffixTree(result, cacheFile, numRoots, firstRootOffset, lowerFileName, fileName.length() - 1, false);
//        if (result.m_matchingMimeTypes.isEmpty())
//            matchSuffixTree(result, cacheFile, numRoots, firstRootOffset, fileName, fileName.length() - 1, true);
//    }
//    if (foundSuffix)
//        *foundSuffix = result.m_foundSuffix;
//    return result.m_matchingMimeTypes;
//}

//void MimeBinaryProvider::matchGlobList(MimeGlobMatchResult &result, CacheFile *cacheFile, int off, const QString &fileName)
//{
//    const int numGlobs = cacheFile->getUint32(off);
//    //qDebug() << "Loading" << numGlobs << "globs from" << cacheFile->file.fileName() << "at offset" << cacheFile->globListOffset;
//    for (int i = 0; i < numGlobs; ++i) {
//        const int globOffset = cacheFile->getUint32(off + 4 + 12 * i);
//        const int mimeTypeOffset = cacheFile->getUint32(off + 4 + 12 * i + 4);
//        const int flagsAndWeight = cacheFile->getUint32(off + 4 + 12 * i + 8);
//        const int weight = flagsAndWeight & 0xff;
//        const bool caseSensitive = flagsAndWeight & 0x100;
//        const Qt::CaseSensitivity qtCaseSensitive = caseSensitive ? Qt::CaseSensitive : Qt::CaseInsensitive;
//        const QString pattern = QLatin1String(cacheFile->getCharStar(globOffset));

//        const char *mimeType = cacheFile->getCharStar(mimeTypeOffset);
//        //qDebug() << pattern << mimeType << weight << caseSensitive;
//        MimeGlobPattern glob(pattern, QString() /*unused*/, weight, qtCaseSensitive);

//        // TODO: this could be done faster for literals where a simple == would do.
//        if (glob.matchFileName(fileName))
//            result.addMatch(QLatin1String(mimeType), weight, pattern);
//    }
//}

//bool MimeBinaryProvider::matchSuffixTree(MimeGlobMatchResult &result, MimeBinaryProvider::CacheFile *cacheFile, int numEntries, int firstOffset, const QString &fileName, int charPos, bool caseSensitiveCheck)
//{
//    QChar fileChar = fileName[charPos];
//    int min = 0;
//    int max = numEntries - 1;
//    while (min <= max) {
//        const int mid = (min + max) / 2;
//        const int off = firstOffset + 12 * mid;
//        const QChar ch = cacheFile->getUint32(off);
//        if (ch < fileChar)
//            min = mid + 1;
//        else if (ch > fileChar)
//            max = mid - 1;
//        else {
//            --charPos;
//            int numChildren = cacheFile->getUint32(off + 4);
//            int childrenOffset = cacheFile->getUint32(off + 8);
//            bool success = false;
//            if (charPos > 0)
//                success = matchSuffixTree(result, cacheFile, numChildren, childrenOffset, fileName, charPos, caseSensitiveCheck);
//            if (!success) {
//                for (int i = 0; i < numChildren; ++i) {
//                    const int childOff = childrenOffset + 12 * i;
//                    const int mch = cacheFile->getUint32(childOff);
//                    if (mch != 0)
//                        break;
//                    const int mimeTypeOffset = cacheFile->getUint32(childOff + 4);
//                    const char *mimeType = cacheFile->getCharStar(mimeTypeOffset);
//                    const int flagsAndWeight = cacheFile->getUint32(childOff + 8);
//                    const int weight = flagsAndWeight & 0xff;
//                    const bool caseSensitive = flagsAndWeight & 0x100;
//                    if (caseSensitiveCheck || !caseSensitive) {
//                        result.addMatch(QLatin1String(mimeType), weight, QLatin1Char('*') + fileName.mid(charPos+1));
//                        success = true;
//                    }
//                }
//            }
//            return success;
//        }
//    }
//    return false;
//}

//bool MimeBinaryProvider::matchMagicRule(MimeBinaryProvider::CacheFile *cacheFile, int numMatchlets, int firstOffset, const QByteArray &data)
//{
//    const char *dataPtr = data.constData();
//    const int dataSize = data.size();
//    for (int matchlet = 0; matchlet < numMatchlets; ++matchlet) {
//        const int off = firstOffset + matchlet * 32;
//        const int rangeStart = cacheFile->getUint32(off);
//        const int rangeLength = cacheFile->getUint32(off + 4);
//        //const int wordSize = cacheFile->getUint32(off + 8);
//        const int valueLength = cacheFile->getUint32(off + 12);
//        const int valueOffset = cacheFile->getUint32(off + 16);
//        const int maskOffset = cacheFile->getUint32(off + 20);
//        const char *mask = maskOffset ? cacheFile->getCharStar(maskOffset) : NULL;

//        if (!MimeMagicRule::matchSubstring(dataPtr, dataSize, rangeStart, rangeLength, valueLength, cacheFile->getCharStar(valueOffset), mask))
//            continue;

//        const int numChildren = cacheFile->getUint32(off + 24);
//        const int firstChildOffset = cacheFile->getUint32(off + 28);
//        if (numChildren == 0) // No submatch? Then we are done.
//            return true;
//        // Check that one of the submatches matches too
//        if (matchMagicRule(cacheFile, numChildren, firstChildOffset, data))
//            return true;
//    }
//    return false;
//}

//MimeType MimeBinaryProvider::findByMagic(const QByteArray &data, int *accuracyPtr)
//{
//    checkCache();
//    foreach (CacheFile *cacheFile, m_cacheFiles) {
//        const int magicListOffset = cacheFile->getUint32(PosMagicListOffset);
//        const int numMatches = cacheFile->getUint32(magicListOffset);
//        //const int maxExtent = cacheFile->getUint32(magicListOffset + 4);
//        const int firstMatchOffset = cacheFile->getUint32(magicListOffset + 8);

//        for (int i = 0; i < numMatches; ++i) {
//            const int off = firstMatchOffset + i * 16;
//            const int numMatchlets = cacheFile->getUint32(off + 8);
//            const int firstMatchletOffset = cacheFile->getUint32(off + 12);
//            if (matchMagicRule(cacheFile, numMatchlets, firstMatchletOffset, data)) {
//                const int mimeTypeOffset = cacheFile->getUint32(off + 4);
//                const char *mimeType = cacheFile->getCharStar(mimeTypeOffset);
//                *accuracyPtr = cacheFile->getUint32(off);
//                // Return the first match. We have no rules for conflicting magic data...
//                // (mime.cache itself is sorted, but what about local overrides with a lower prio?)
//                return mimeTypeForNameUnchecked(QLatin1String(mimeType));
//            }
//        }
//    }
//    return MimeType();
//}

//QStringList MimeBinaryProvider::parents(const QString &mime)
//{
//    checkCache();
//    const QByteArray mimeStr = mime.toLatin1();
//    QStringList result;
//    foreach (CacheFile *cacheFile, m_cacheFiles) {
//        const int parentListOffset = cacheFile->getUint32(PosParentListOffset);
//        const int numEntries = cacheFile->getUint32(parentListOffset);

//        int begin = 0;
//        int end = numEntries - 1;
//        while (begin <= end) {
//            const int medium = (begin + end) / 2;
//            const int off = parentListOffset + 4 + 8 * medium;
//            const int mimeOffset = cacheFile->getUint32(off);
//            const char *aMime = cacheFile->getCharStar(mimeOffset);
//            const int cmp = qstrcmp(aMime, mimeStr);
//            if (cmp < 0) {
//                begin = medium + 1;
//            } else if (cmp > 0) {
//                end = medium - 1;
//            } else {
//                const int parentsOffset = cacheFile->getUint32(off + 4);
//                const int numParents = cacheFile->getUint32(parentsOffset);
//                for (int i = 0; i < numParents; ++i) {
//                    const int parentOffset = cacheFile->getUint32(parentsOffset + 4 + 4 * i);
//                    const char *aParent = cacheFile->getCharStar(parentOffset);
//                    result.append(QString::fromLatin1(aParent));
//                }
//                break;
//            }
//        }
//    }
//    if (result.isEmpty()) {
//        const QString parent = fallbackParent(mime);
//        if (!parent.isEmpty())
//            result.append(parent);
//    }
//    return result;
//}

//QString MimeBinaryProvider::resolveAlias(const QString &name)
//{
//    checkCache();
//    const QByteArray input = name.toLatin1();
//    foreach (CacheFile *cacheFile, m_cacheFiles) {
//        const int aliasListOffset = cacheFile->getUint32(PosAliasListOffset);
//        const int numEntries = cacheFile->getUint32(aliasListOffset);
//        int begin = 0;
//        int end = numEntries - 1;
//        while (begin <= end) {
//            const int medium = (begin + end) / 2;
//            const int off = aliasListOffset + 4 + 8 * medium;
//            const int aliasOffset = cacheFile->getUint32(off);
//            const char *alias = cacheFile->getCharStar(aliasOffset);
//            const int cmp = qstrcmp(alias, input);
//            if (cmp < 0) {
//                begin = medium + 1;
//            } else if (cmp > 0) {
//                end = medium - 1;
//            } else {
//                const int mimeOffset = cacheFile->getUint32(off + 4);
//                const char *mimeType = cacheFile->getCharStar(mimeOffset);
//                return QLatin1String(mimeType);
//            }
//        }
//    }

//    return name;
//}

//QStringList MimeBinaryProvider::listAliases(const QString &name)
//{
//    checkCache();
//    QStringList result;
//    const QByteArray input = name.toLatin1();
//    foreach (CacheFile *cacheFile, m_cacheFiles) {
//        const int aliasListOffset = cacheFile->getUint32(PosAliasListOffset);
//        const int numEntries = cacheFile->getUint32(aliasListOffset);
//        for (int pos = 0; pos < numEntries; ++pos) {
//            const int off = aliasListOffset + 4 + 8 * pos;
//            const int mimeOffset = cacheFile->getUint32(off + 4);
//            const char *mimeType = cacheFile->getCharStar(mimeOffset);

//            if (input == mimeType) {
//                const int aliasOffset = cacheFile->getUint32(off);
//                const char *alias = cacheFile->getCharStar(aliasOffset);
//                result.append(QString::fromLatin1(alias));
//            }
//        }
//    }
//    return result;
//}

//void MimeBinaryProvider::loadMimeTypeList()
//{
//    if (!m_mimetypeListLoaded) {
//        m_mimetypeListLoaded = true;
//        m_mimetypeNames.clear();
//        // Unfortunately mime.cache doesn't have a full list of all mimetypes.
//        // So we have to parse the plain-text files called "types".
//        const QStringList typesFilenames = QStandardPaths::locateAll(QStandardPaths::GenericDataLocation, QLatin1String("mime/types"));
//        foreach (const QString &typeFilename, typesFilenames) {
//            QFile file(typeFilename);
//            if (file.open(QIODevice::ReadOnly)) {
//                while (!file.atEnd()) {
//                    QByteArray line = file.readLine();
//                    line.chop(1);
//                    m_mimetypeNames.insert(QString::fromLatin1(line.constData(), line.size()));
//                }
//            }
//        }
//    }
//}

//QList<MimeType> MimeBinaryProvider::allMimeTypes()
//{
//    QList<MimeType> result;
//    loadMimeTypeList();

//    for (QSet<QString>::const_iterator it = m_mimetypeNames.constBegin();
//          it != m_mimetypeNames.constEnd(); ++it)
//        result.append(mimeTypeForNameUnchecked(*it));

//    return result;
//}

//void MimeBinaryProvider::loadMimeTypePrivate(MimeTypePrivate &data)
//{
//#ifdef QT_NO_XMLSTREAMREADER
//    qWarning() << "Cannot load mime type since QXmlStreamReader is not available.";
//    return;
//#else
//    if (data.loaded)
//        return;
//    data.loaded = true;
//    // load comment and globPatterns

//    const QString file = data.name + QLatin1String(".xml");
//    const QStringList mimeFiles = QStandardPaths::locateAll(QStandardPaths::GenericDataLocation, QString::fromLatin1("mime/") + file);
//    if (mimeFiles.isEmpty()) {
//        // TODO: ask Thiago about this
//        qWarning() << "No file found for" << file << ", even though the file appeared in a directory listing.";
//        qWarning() << "Either it was just removed, or the directory doesn't have executable permission...";
//        qWarning() << QStandardPaths::locateAll(QStandardPaths::GenericDataLocation, QLatin1String("mime"), QStandardPaths::LocateDirectory);
//        return;
//    }

//    QString comment;
//    QString mainPattern;
//    const QString preferredLanguage = QLocale::system().name();

//    QListIterator<QString> mimeFilesIter(mimeFiles);
//    mimeFilesIter.toBack();
//    while (mimeFilesIter.hasPrevious()) { // global first, then local.
//        const QString fullPath = mimeFilesIter.previous();
//        QFile qfile(fullPath);
//        if (!qfile.open(QFile::ReadOnly))
//            continue;

//        QXmlStreamReader xml(&qfile);
//        if (xml.readNextStartElement()) {
//            if (xml.name() != QLatin1String("mime-type")) {
//                continue;
//            }
//            const QString name = xml.attributes().value(QLatin1String("type")).toString();
//            if (name.isEmpty())
//                continue;
//            if (name != data.name) {
//                qWarning() << "Got name" << name << "in file" << file << "expected" << data.name;
//            }

//            while (xml.readNextStartElement()) {
//                const QStringRef tag = xml.name();
//                if (tag == QLatin1String("comment")) {
//                    QString lang = xml.attributes().value(QLatin1String("xml:lang")).toString();
//                    const QString text = xml.readElementText();
//                    if (lang.isEmpty()) {
//                        lang = QLatin1String("en_US");
//                    }
//                    data.localeComments.insert(lang, text);
//                    continue; // we called readElementText, so we're at the EndElement already.
//                } else if (tag == QLatin1String("icon")) { // as written out by shared-mime-info >= 0.40
//                    data.iconName = xml.attributes().value(QLatin1String("name")).toString();
//                } else if (tag == QLatin1String("glob-deleteall")) { // as written out by shared-mime-info >= 0.70
//                    data.globPatterns.clear();
//                } else if (tag == QLatin1String("glob")) { // as written out by shared-mime-info >= 0.70
//                    const QString pattern = xml.attributes().value(QLatin1String("pattern")).toString();
//                    if (mainPattern.isEmpty() && pattern.startsWith(QLatin1Char('*'))) {
//                        mainPattern = pattern;
//                    }
//                    if (!data.globPatterns.contains(pattern))
//                        data.globPatterns.append(pattern);
//                }
//                xml.skipCurrentElement();
//            }
//            Q_ASSERT(xml.name() == QLatin1String("mime-type"));
//        }
//    }

//    // Let's assume that shared-mime-info is at least version 0.70
//    // Otherwise we would need 1) a version check, and 2) code for parsing patterns from the globs file.
//#if 1
//    if (!mainPattern.isEmpty() && data.globPatterns.first() != mainPattern) {
//        // ensure it's first in the list of patterns
//        data.globPatterns.removeAll(mainPattern);
//        data.globPatterns.prepend(mainPattern);
//    }
//#else
//    const bool globsInXml = sharedMimeInfoVersion() >= QT_VERSION_CHECK(0, 70, 0);
//    if (globsInXml) {
//        if (!mainPattern.isEmpty() && data.globPatterns.first() != mainPattern) {
//            // ensure it's first in the list of patterns
//            data.globPatterns.removeAll(mainPattern);
//            data.globPatterns.prepend(mainPattern);
//        }
//    } else {
//        // Fallback: get the patterns from the globs file
//        // TODO: This would be the only way to support shared-mime-info < 0.70
//        // But is this really worth the effort?
//    }
//#endif
//#endif //QT_NO_XMLSTREAMREADER
//}

//// Binary search in the icons or generic-icons list
//QString MimeBinaryProvider::iconForMime(CacheFile *cacheFile, int posListOffset, const QByteArray &inputMime)
//{
//    const int iconsListOffset = cacheFile->getUint32(posListOffset);
//    const int numIcons = cacheFile->getUint32(iconsListOffset);
//    int begin = 0;
//    int end = numIcons - 1;
//    while (begin <= end) {
//        const int medium = (begin + end) / 2;
//        const int off = iconsListOffset + 4 + 8 * medium;
//        const int mimeOffset = cacheFile->getUint32(off);
//        const char *mime = cacheFile->getCharStar(mimeOffset);
//        const int cmp = qstrcmp(mime, inputMime);
//        if (cmp < 0)
//            begin = medium + 1;
//        else if (cmp > 0)
//            end = medium - 1;
//        else {
//            const int iconOffset = cacheFile->getUint32(off + 4);
//            return QLatin1String(cacheFile->getCharStar(iconOffset));
//        }
//    }
//    return QString();
//}

//void MimeBinaryProvider::loadIcon(MimeTypePrivate &data)
//{
//    checkCache();
//    const QByteArray inputMime = data.name.toLatin1();
//    foreach (CacheFile *cacheFile, m_cacheFiles) {
//        const QString icon = iconForMime(cacheFile, PosIconsListOffset, inputMime);
//        if (!icon.isEmpty()) {
//            data.iconName = icon;
//            return;
//        }
//    }
//}

//void MimeBinaryProvider::loadGenericIcon(MimeTypePrivate &data)
//{
//    checkCache();
//    const QByteArray inputMime = data.name.toLatin1();
//    foreach (CacheFile *cacheFile, m_cacheFiles) {
//        const QString icon = iconForMime(cacheFile, PosGenericIconsListOffset, inputMime);
//        if (!icon.isEmpty()) {
//            data.genericIconName = icon;
//            return;
//        }
//    }
//}

////

MimeXMLProvider::MimeXMLProvider(MimeDatabasePrivate *db)
    : MimeProviderBase(db), m_loaded(false)
{
}

bool MimeXMLProvider::isValid()
{
    return true;
}

MimeType MimeXMLProvider::mimeTypeForName(const QString &name)
{
    ensureLoaded();

    return m_nameMimeTypeMap.value(name);
}

QStringList MimeXMLProvider::findByFileName(const QString &fileName, QString *foundSuffix)
{
    ensureLoaded();

    const QStringList matchingMimeTypes = m_mimeTypeGlobs.matchingGlobs(fileName, foundSuffix);
    return matchingMimeTypes;
}

MimeType MimeXMLProvider::findByMagic(const QByteArray &data, int *accuracyPtr)
{
    ensureLoaded();

    QString candidate;

    foreach (const MimeMagicRuleMatcher &matcher, m_magicMatchers) {
        if (matcher.matches(data)) {
            const int priority = matcher.priority();
            if (priority > *accuracyPtr) {
                *accuracyPtr = priority;
                candidate = matcher.mimetype();
            }
        }
    }
    return mimeTypeForName(candidate);
}

QMap<int, QList<MimeMagicRule> > MimeXMLProvider::magicRulesForMimeType(const MimeType &mimeType)
{
    QMap<int, QList<MimeMagicRule> > result;
    foreach (const MimeMagicRuleMatcher &matcher, m_magicMatchers) {
        if (mimeType.matchesName(matcher.mimetype()))
            result[matcher.priority()].append(matcher.magicRules());
    }
    return result;
}

void MimeXMLProvider::setGlobPatternsForMimeType(const MimeType &mimeType, const QStringList &patterns)
{
    // remove all previous globs
    m_mimeTypeGlobs.removeMimeType(mimeType.name());
    // add new patterns as case-insensitive default-weight patterns
    foreach (const QString &pattern, patterns)
        addGlobPattern(MimeGlobPattern(pattern, mimeType.name()));
    mimeType.d->globPatterns = patterns;
}

void MimeXMLProvider::setMagicRulesForMimeType(const MimeType &mimeType, const QMap<int, QList<MimeMagicRule> > &rules)
{
    // remove all previous rules
    QMutableListIterator<MimeMagicRuleMatcher> matcherIt(m_magicMatchers);
    while (matcherIt.hasNext()) {
        if (matcherIt.next().mimetype() == mimeType.name())
            matcherIt.remove();
    }
    // add new rules
    for (auto it = rules.constBegin(); it != rules.constEnd(); ++it) {
        MimeMagicRuleMatcher matcher(mimeType.name(), it.key()/*priority*/);
        matcher.addRules(it.value());
        addMagicMatcher(matcher);
    }
}

void MimeXMLProvider::ensureLoaded()
{
    if (!m_loaded /*|| shouldCheck()*/) {
        m_loaded = true;
        QStringList allFiles = QStandardPaths::locateAll(QStandardPaths::GenericDataLocation,
                                                         QStringLiteral("mime/packages/freedesktop.org.xml"),
                                                         QStandardPaths::LocateFile);

        if (allFiles.isEmpty()) {
            // System freedesktop.org.xml file not found, try to use the one in QtCore.
            // This is private API and has changed in the past:
            // - Qt 5.11 added "package" subdir in 7a5644d6481a3c1a7416772998ca4e60c977bfbd
            // - Qt 5.13 added an option to not bundle it at all
            const QString fdoXml5_11 = QStringLiteral(":/qt-project.org/qmime/packages/freedesktop.org.xml");
            const QString fdoXmlPre5_11 = QStringLiteral(":/qt-project.org/qmime/freedesktop.org.xml");
            if (QFile::exists(fdoXml5_11))
                allFiles << fdoXml5_11;
            else if (QFile::exists(fdoXmlPre5_11))
                allFiles << fdoXmlPre5_11;
            else
                qFatal("Utils::MimeXMLProvider: could not find the system freedesktop.org.xml file "
                       "and QtCore does not have an accessible copy.");
        }

        m_nameMimeTypeMap.clear();
        m_aliases.clear();
        m_parents.clear();
        m_mimeTypeGlobs.clear();
        m_magicMatchers.clear();

        //qDebug() << "Loading" << m_allFiles;

        // add custom mime types first, which override any default from freedesktop.org.xml
        MimeTypeParser parser(*this);
        QHashIterator<QString, QByteArray> it(m_additionalData);
        while (it.hasNext()) {
            it.next();
            QString errorMessage;
            if (!parser.parse(it.value(), it.key(), &errorMessage)) {
                qWarning("MimeDatabase: Error loading %s\n%s", qPrintable(it.key()),
                         qPrintable(errorMessage));
            }
        }
        foreach (const QString &file, allFiles)
            load(file);
    }
}

void MimeXMLProvider::load(const QString &fileName)
{
    QString errorMessage;
    if (!load(fileName, &errorMessage))
        qWarning("MimeDatabase: Error loading %s\n%s", qPrintable(fileName), qPrintable(errorMessage));
}

bool MimeXMLProvider::load(const QString &fileName, QString *errorMessage)
{
    m_loaded = true;

    QFile file(fileName);
    if (!file.open(QIODevice::ReadOnly | QIODevice::Text)) {
        if (errorMessage)
            *errorMessage = QString::fromLatin1("Cannot open %1: %2").arg(fileName, file.errorString());
        return false;
    }

    if (errorMessage)
        errorMessage->clear();

    const QByteArray content = file.readAll();
    MimeTypeParser parser(*this);
    return parser.parse(content, fileName, errorMessage);
}

void MimeXMLProvider::addGlobPattern(const MimeGlobPattern &glob)
{
    m_mimeTypeGlobs.addGlob(glob);
}

void MimeXMLProvider::addMimeType(const MimeType &mt)
{
    m_nameMimeTypeMap.insert(mt.name(), mt);
}

QStringList MimeXMLProvider::parents(const QString &mime)
{
    ensureLoaded();
    QStringList result = m_parents.value(mime);
    if (result.isEmpty()) {
        const QString parent = fallbackParent(mime);
        if (!parent.isEmpty())
            result.append(parent);
    }
    return result;
}

void MimeXMLProvider::addParent(const QString &child, const QString &parent)
{
    m_parents[child].append(parent);
}

QStringList MimeXMLProvider::listAliases(const QString &name)
{
    ensureLoaded();
    // Iterate through the whole hash. This method is rarely used.
    return m_aliases.keys(name);
}

QString MimeXMLProvider::resolveAlias(const QString &name)
{
    ensureLoaded();
    return m_aliases.value(name, name);
}

void MimeXMLProvider::addAlias(const QString &alias, const QString &name)
{
    m_aliases.insert(alias, name);
}

QList<MimeType> MimeXMLProvider::allMimeTypes()
{
    ensureLoaded();
    return m_nameMimeTypeMap.values();
}

void MimeXMLProvider::addMagicMatcher(const MimeMagicRuleMatcher &matcher)
{
    m_magicMatchers.append(matcher);
}

void MimeXMLProvider::addData(const QString &id, const QByteArray &data)
{
    if (m_additionalData.contains(id))
        qWarning("Overwriting data in mime database, id '%s'", qPrintable(id));
    m_additionalData.insert(id, data);
    m_loaded = false; // force reload to ensure correct load order for overridden mime types
}