qfontengine_qpf.cpp

奇趣公司比较新的qt/emd版本

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#include "qfontengine_qpf_p.h"

#include "private/qpaintengine_raster_p.h"
#include <QtCore/qlibraryinfo.h>
#include <QtCore/qfileinfo.h>

#include <QtCore/qfile.h>
#include <QtCore/qdir.h>
#include <QtCore/qbuffer.h>
#if !defined(QT_NO_FREETYPE)
#include "private/qfontengine_ft_p.h"
#include "qopentype_p.h"
#endif

// for mmap
#include <stdlib.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/mman.h>
#include <fcntl.h>
#include <errno.h>

#ifndef QT_NO_QWS_QPF

#include "qpfutil.cpp"

#if defined(Q_WS_QWS)
#include "private/qwscommand_qws_p.h"
#include "qwsdisplay_qws.h"
#include "qabstractfontengine_p.h"
#endif
#include "qplatformdefs.h"

#ifdef QT_LSB

#include <dlfcn.h>

#  ifdef QT_NO_MREMAP
#    undef QT_NO_MREMAP
#  endif
#  define MREMAP_MAYMOVE 1
#  define RTLD_DEFAULT   ((void *) 0)

// LSB doesn't standardize mremap - resolve it dynamically at runtime
static void *mremap (void *__addr, size_t __old_len, size_t __new_len, int __flags)
{
    typedef void *(*RemapAddress)(void*, size_t, size_t, int, ...);
    static RemapAddress remapAddr = 0;
    if (!remapAddr) {
        *(void **)(&remapAddr) = ::dlsym(RTLD_DEFAULT, "mremap");
        if (!remapAddr)
            qFatal("Unable to call mremap");
    }

    return remapAddr(__addr, __old_len, __new_len, __flags);
}
#endif

//#define DEBUG_HEADER
//#define DEBUG_FONTENGINE

#if defined(DEBUG_HEADER)
# define DEBUG_VERIFY qDebug
#else
# define DEBUG_VERIFY if (0) qDebug
#endif

#define READ_VERIFY(type, variable) \
    if (tagPtr + sizeof(type) > endPtr) { \
        DEBUG_VERIFY() << "read verify failed in line" << __LINE__; \
        return 0; \
    } \
    variable = qFromBigEndian<type>(tagPtr); \
    DEBUG_VERIFY() << "read value" << variable << "of type " #type; \
    tagPtr += sizeof(type)

template <typename T>
T readValue(const uchar *&data)
{
    T value = qFromBigEndian<T>(data);
    data += sizeof(T);
    return value;
}

#define VERIFY(condition) \
    if (!(condition)) { \
        DEBUG_VERIFY() << "condition " #condition " failed in line" << __LINE__; \
        return 0; \
    }

#define VERIFY_TAG(condition) \
    if (!(condition)) { \
        DEBUG_VERIFY() << "verifying tag condition " #condition " failed in line" << __LINE__ << "with tag" << tag; \
        return 0; \
    }

static inline const uchar *verifyTag(const uchar *tagPtr, const uchar *endPtr)
{
    quint16 tag, length;
    READ_VERIFY(quint16, tag);
    READ_VERIFY(quint16, length);
    if (tag == QFontEngineQPF::Tag_EndOfHeader)
        return endPtr;
    if (tag < QFontEngineQPF::NumTags) {
        switch (tagTypes[tag]) {
            case QFontEngineQPF::BitFieldType:
            case QFontEngineQPF::StringType:
                // can't do anything...
                break;
            case QFontEngineQPF::UInt32Type:
                VERIFY_TAG(length == sizeof(quint32));
                break;
            case QFontEngineQPF::FixedType:
                VERIFY_TAG(length == sizeof(quint32));
                break;
            case QFontEngineQPF::UInt8Type:
                VERIFY_TAG(length == sizeof(quint8));
                break;
        }
#if defined(DEBUG_HEADER)
        if (length == 1)
            qDebug() << "tag data" << hex << *tagPtr;
        else if (length == 4)
            qDebug() << "tag data" << hex << tagPtr[0] << tagPtr[1] << tagPtr[2] << tagPtr[3];
#endif
    }
    return tagPtr + length;
}

const QFontEngineQPF::Glyph *QFontEngineQPF::findGlyph(glyph_t g) const
{
    if (!g || g >= glyphMapEntries)
        return 0;
    const quint32 *gmapPtr = reinterpret_cast<const quint32 *>(fontData + glyphMapOffset);
    quint32 glyphPos = qFromBigEndian<quint32>(gmapPtr[g]);
    if (glyphPos > glyphDataSize) {
        if (glyphPos == 0xffffffff)
            return 0;
#if defined(DEBUG_FONTENGINE)
        qDebug() << "glyph" << g << "outside of glyphData, remapping font file";
#endif
#ifndef QT_NO_FREETYPE
        const_cast<QFontEngineQPF *>(this)->remapFontData();
#endif
        if (glyphPos > glyphDataSize)
            return 0;
    }
    return reinterpret_cast<const Glyph *>(fontData + glyphDataOffset + glyphPos);
}

bool QFontEngineQPF::verifyHeader(const uchar *data, int size)
{
    VERIFY(size >= int(sizeof(Header)));
    const Header *header = reinterpret_cast<const Header *>(data);
    if (header->magic[0] != 'Q'
        || header->magic[1] != 'P'
        || header->magic[2] != 'F'
        || header->magic[3] != '2')
        return false;

    VERIFY(header->majorVersion <= CurrentMajorVersion);
    const quint16 dataSize = qFromBigEndian<quint16>(header->dataSize);
    VERIFY(size >= int(sizeof(Header)) + dataSize);

    const uchar *tagPtr = data + sizeof(Header);
    const uchar *tagEndPtr = tagPtr + dataSize;
    while (tagPtr < tagEndPtr - 3) {
        tagPtr = verifyTag(tagPtr, tagEndPtr);
        VERIFY(tagPtr);
    }

    VERIFY(tagPtr <= tagEndPtr);
    return true;
}

QVariant QFontEngineQPF::extractHeaderField(const uchar *data, HeaderTag requestedTag)
{
    const Header *header = reinterpret_cast<const Header *>(data);
    const uchar *tagPtr = data + sizeof(Header);
    const uchar *endPtr = tagPtr + qFromBigEndian<quint16>(header->dataSize);
    while (tagPtr < endPtr - 3) {
        quint16 tag = readValue<quint16>(tagPtr);
        quint16 length = readValue<quint16>(tagPtr);
        if (tag == requestedTag) {
            switch (tagTypes[requestedTag]) {
                case StringType:
                    return QVariant(QString::fromUtf8(reinterpret_cast<const char *>(tagPtr), length));
                case UInt32Type:
                    return QVariant(readValue<quint32>(tagPtr));
                case UInt8Type:
                    return QVariant(uint(*tagPtr));
                case FixedType:
                    return QVariant(QFixed::fromFixed(readValue<quint32>(tagPtr)).toReal());
                case BitFieldType:
                    return QVariant(QByteArray(reinterpret_cast<const char *>(tagPtr), length));
            }
            return QVariant();
        } else if (tag == Tag_EndOfHeader) {
            break;
        }
        tagPtr += length;
    }

    return QVariant();
}

#endif // QT_NO_QWS_QPF

QString qws_fontCacheDir()
{
    static QString dir;
    if (!dir.isEmpty())
        return dir;
#if defined(Q_WS_QWS)
    extern QString qws_dataDir();
    dir = qws_dataDir();
#else
    dir = QDir::tempPath();
#endif
    dir.append(QLatin1String("/fonts/"));
    QDir qd(dir);
    if (!qd.exists() && !qd.mkpath(dir))
        dir = QDir::tempPath();
    return dir;
}

#ifndef QT_NO_QWS_QPF

QList<QByteArray> QFontEngineQPF::cleanUpAfterClientCrash(const QList<int> &crashedClientIds)
{
    QList<QByteArray> removedFonts;
    QDir dir(qws_fontCacheDir(), QLatin1String("*.qsf"));
    for (int i = 0; i < int(dir.count()); ++i) {
        const QByteArray fileName = QFile::encodeName(dir.absoluteFilePath(dir[i]));

        int fd = ::open(fileName.constData(), O_RDONLY);
        if (fd >= 0) {
            void *header = ::mmap(0, sizeof(QFontEngineQPF::Header), PROT_READ, MAP_SHARED, fd, 0);
            if (header && header != MAP_FAILED) {
                quint32 lockValue = reinterpret_cast<QFontEngineQPF::Header *>(header)->lock;

                if (lockValue && crashedClientIds.contains(lockValue)) {
                    removedFonts.append(fileName);
                    QFile::remove(QFile::decodeName(fileName));
                }

                ::munmap(header, sizeof(QFontEngineQPF::Header));
            }
            ::close(fd);
        }
    }
    if (!removedFonts.isEmpty())
        qDebug() << "list of corrupted and removed fonts:" << removedFonts;
    return removedFonts;
}

static inline unsigned int getChar(const QChar *str, int &i, const int len)
{
    unsigned int uc = str[i].unicode();
    if (uc >= 0xd800 && uc < 0xdc00 && i < len-1) {
        uint low = str[i+1].unicode();
       if (low >= 0xdc00 && low < 0xe000) {
            uc = (uc - 0xd800)*0x400 + (low - 0xdc00) + 0x10000;
            ++i;
        }
    }
    return uc;
}

QFontEngineQPF::QFontEngineQPF(const QFontDef &def, int fileDescriptor, QFontEngine *fontEngine)
    : fd(fileDescriptor), renderingFontEngine(fontEngine)
{
    fontData = 0;
    dataSize = 0;
    fontDef = def;
    cache_cost = 100;
    freetype = 0;
    _openType = 0;
    externalCMap = 0;
    cmapOffset = 0;
    cmapSize = 0;
    glyphMapOffset = 0;
    glyphMapEntries = 0;
    glyphDataOffset = 0;
    glyphDataSize = 0;
    kerning_pairs_loaded = false;
    readOnly = true;

#if defined(DEBUG_FONTENGINE)
    qDebug() << "QFontEngineQPF::QFontEngineQPF( fd =" << fd << ", renderingFontEngine =" << renderingFontEngine << ")";
#endif

    if (fd < 0) {
        if (!renderingFontEngine)
            return;

        fileName = fontDef.family.toLower() + QLatin1String("_")
                   + QString::number(fontDef.pixelSize)
                   + QLatin1String("_") + QString::number(fontDef.weight)
                   + (fontDef.style != QFont::StyleNormal ?
                      QLatin1String("_italic") : QLatin1String(""))
                   + QLatin1String(".qsf");
        fileName.replace(QLatin1Char(' '), QLatin1Char('_'));
        fileName.prepend(qws_fontCacheDir());

        const QByteArray encodedName = QFile::encodeName(fileName);
        if (::access(encodedName, F_OK) == 0) {
#if defined(DEBUG_FONTENGINE)
            qDebug() << "found existing qpf:" << fileName;
#endif
            if (::access(encodedName, W_OK | R_OK) == 0)
                fd = ::open(encodedName, O_RDWR);
            else if (::access(encodedName, R_OK) == 0)
                fd = ::open(encodedName, O_RDONLY);
        } else {
#if defined(DEBUG_FONTENGINE)
            qDebug() << "creating qpf on the fly:" << fileName;
#endif
            if (::access(QFile::encodeName(qws_fontCacheDir()), W_OK) == 0) {
                fd = ::open(encodedName, O_RDWR | O_EXCL | O_CREAT, 0644);

                QBuffer buffer;
                buffer.open(QIODevice::ReadWrite);
                QPFGenerator generator(&buffer, renderingFontEngine);
                generator.generate();
                buffer.close();
                const QByteArray &data = buffer.data();
                ::write(fd, data.constData(), data.size());
            }
        }
    }

    QT_STATBUF st;
    if (QT_FSTAT(fd, &st)) {
#if defined(DEBUG_FONTENGINE)
        qDebug() << "stat failed!";
#endif
        return;
    }
    dataSize = st.st_size;


    fontData = (const uchar *)::mmap(0, st.st_size, PROT_READ | (renderingFontEngine ? PROT_WRITE : 0), MAP_SHARED, fd, 0);