qfont_x11.cpp

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#define QT_FATAL_ASSERT

#include "qplatformdefs.h"

#include "qfont.h"
#include "qapplication.h"
#include "qfontinfo.h"
#include "qfontdatabase.h"
#include "qfontmetrics.h"
#include "qpaintdevice.h"
#include "qtextcodec.h"
#include "qiodevice.h"
#include "qhash.h"

#include <private/qunicodetables_p.h>
#include "qfont_p.h"
#include "qfontengine_p.h"
#include "qfontengine_x11_p.h"
#include "qtextengine_p.h"

#include <private/qt_x11_p.h>
#include "qx11info_x11.h"

#include <time.h>
#include <stdlib.h>
#include <ctype.h>

#define QFONTLOADER_DEBUG
#define QFONTLOADER_DEBUG_VERBOSE

QT_BEGIN_NAMESPACE

double qt_pixelSize(double pointSize, int dpi)
{
    if (pointSize < 0)
        return -1.;
    if (dpi == 75) // the stupid 75 dpi setting on X11
        dpi = 72;
    return (pointSize * dpi) /72.;
}

double qt_pointSize(double pixelSize, int dpi)
{
    if (pixelSize < 0)
        return -1.;
    if (dpi == 75) // the stupid 75 dpi setting on X11
        dpi = 72;
    return pixelSize * 72. / ((double) dpi);
}

/*
  Removes wildcards from an XLFD.

  Returns \a xlfd with all wildcards removed if a match for \a xlfd is
  found, otherwise it returns \a xlfd.
*/
static QByteArray qt_fixXLFD(const QByteArray &xlfd)
{
    QByteArray ret = xlfd;
    int count = 0;
    char **fontNames =
        XListFonts(QX11Info::display(), xlfd, 32768, &count);
    if (count > 0)
        ret = fontNames[0];
    XFreeFontNames(fontNames);
    return ret ;
}

typedef QHash<int, QString> FallBackHash;
Q_GLOBAL_STATIC(FallBackHash, fallBackHash)

// Returns the user-configured fallback family for the specified script.
QString qt_fallback_font_family(int script)
{
    FallBackHash *hash = fallBackHash();
    return hash->value(script);
}

// Sets the fallback family for the specified script.
Q_GUI_EXPORT void qt_x11_set_fallback_font_family(int script, const QString &family)
{
    FallBackHash *hash = fallBackHash();
    if (!family.isEmpty())
        hash->insert(script, family);
    else
        hash->remove(script);
}

int QFontPrivate::defaultEncodingID = -1;

void QFont::initialize()
{
    extern int qt_encoding_id_for_mib(int mib); // from qfontdatabase_x11.cpp
    QTextCodec *codec = QTextCodec::codecForLocale();
    // determine the default encoding id using the locale, otherwise
    // fallback to latin1 (mib == 4)
    int mib = codec ? codec->mibEnum() : 4;

    // for asian locales, use the mib for the font codec instead of the locale codec
    switch (mib) {
    case 38: // eucKR
        mib = 36;
        break;

    case 2025: // GB2312
        mib = 57;
        break;

    case 113: // GBK
        mib = -113;
        break;

    case 114: // GB18030
        mib = -114;
        break;

    case 2026: // Big5
        mib = -2026;
        break;

    case 2101: // Big5-HKSCS
        mib = -2101;
        break;

    case 16: // JIS7
        mib = 15;
        break;

    case 17: // SJIS
    case 18: // eucJP
        mib = 63;
        break;
    }

    // get the default encoding id for the locale encoding...
    QFontPrivate::defaultEncodingID = qt_encoding_id_for_mib(mib);
}

void QFont::cleanup()
{
    QFontCache::cleanup();
}

int QFont::x11Screen() const
{
    return d->screen;
}

void QFont::x11SetScreen(int screen)
{
    if (screen < 0) // assume default
        screen = QX11Info::appScreen();

    if (screen == d->screen)
        return; // nothing to do

    detach();
    d->screen = screen;
}

Qt::HANDLE QFont::handle() const
{
    QFontEngine *engine = d->engineForScript(QUnicodeTables::Common);
    Q_ASSERT(engine != 0);
    if (engine->type() == QFontEngine::Multi)
        engine = static_cast<QFontEngineMulti *>(engine)->engine(0);
    if (engine->type() == QFontEngine::XLFD)
        return static_cast<QFontEngineXLFD *>(engine)->fontStruct()->fid;
    return 0;
}


FT_Face QFont::freetypeFace() const
{
#ifndef QT_NO_FREETYPE
    QFontEngine *engine = d->engineForScript(QUnicodeTables::Common);
    if (engine->type() == QFontEngine::Multi)
        engine = static_cast<QFontEngineMulti *>(engine)->engine(0);
#ifndef QT_NO_FONTCONFIG
    if (engine->type() == QFontEngine::Freetype) {
        const QFontEngineFT *ft = static_cast<const QFontEngineFT *>(engine);
        return ft->non_locked_face();
    } else
#endif
    if (engine->type() == QFontEngine::XLFD) {
        const QFontEngineXLFD *xlfd = static_cast<const QFontEngineXLFD *>(engine);
        return xlfd->non_locked_face();
    }
#endif
    return 0;
}

QString QFont::rawName() const
{
    QFontEngine *engine = d->engineForScript(QUnicodeTables::Common);
    Q_ASSERT(engine != 0);
    if (engine->type() == QFontEngine::Multi)
        engine = static_cast<QFontEngineMulti *>(engine)->engine(0);
    if (engine->type() == QFontEngine::XLFD)
        return QString::fromLatin1(engine->name());
    return QString();
}
struct QtFontDesc;

void QFont::setRawName(const QString &name)
{
    detach();

    // from qfontdatabase_x11.cpp
    extern bool qt_fillFontDef(const QByteArray &xlfd, QFontDef *fd, int dpi, QtFontDesc *desc);

    if (!qt_fillFontDef(qt_fixXLFD(name.toLatin1()), &d->request, d->dpi, 0)) {
        qWarning("QFont::setRawName: Invalid XLFD: \"%s\"", name.toLatin1().constData());

        setFamily(name);
        setRawMode(true);
    } else {
        resolve_mask = QFont::AllPropertiesResolved;
    }
}

QString QFont::lastResortFamily() const
{
    return QString::fromLatin1("Helvetica");
}

QString QFont::defaultFamily() const
{
    switch (d->request.styleHint) {
    case QFont::Times:
        return QString::fromLatin1("Times");

    case QFont::Courier:
        return QString::fromLatin1("Courier");

    case QFont::Monospace:
        return QString::fromLatin1("Courier New");

    case QFont::Cursive:
        return QString::fromLatin1("Comic Sans MS");

    case QFont::Fantasy:
        return QString::fromLatin1("Impact");

    case QFont::Decorative:
        return QString::fromLatin1("Old English");

    case QFont::Helvetica:
    case QFont::System:
    default:
        return QString::fromLatin1("Helvetica");
    }
}

/*
  Returns a last resort raw font name for the font matching algorithm.
  This is used if even the last resort family is not available. It
  returns \e something, almost no matter what.  The current
  implementation tries a wide variety of common fonts, returning the
  first one it finds. The implementation may change at any time.
*/
static const char * const tryFonts[] = {
    "-*-helvetica-medium-r-*-*-*-120-*-*-*-*-*-*",
    "-*-courier-medium-r-*-*-*-120-*-*-*-*-*-*",
    "-*-times-medium-r-*-*-*-120-*-*-*-*-*-*",
    "-*-lucida-medium-r-*-*-*-120-*-*-*-*-*-*",
    "-*-helvetica-*-*-*-*-*-120-*-*-*-*-*-*",
    "-*-courier-*-*-*-*-*-120-*-*-*-*-*-*",
    "-*-times-*-*-*-*-*-120-*-*-*-*-*-*",
    "-*-lucida-*-*-*-*-*-120-*-*-*-*-*-*",
    "-*-helvetica-*-*-*-*-*-*-*-*-*-*-*-*",
    "-*-courier-*-*-*-*-*-*-*-*-*-*-*-*",
    "-*-times-*-*-*-*-*-*-*-*-*-*-*-*",
    "-*-lucida-*-*-*-*-*-*-*-*-*-*-*-*",
    "-*-fixed-*-*-*-*-*-*-*-*-*-*-*-*",
    "6x13",
    "7x13",
    "8x13",
    "9x15",
    "fixed",
    0
};

// Returns true if the font exists, false otherwise
static bool fontExists(const QString &fontName)
{
    int count;
    char **fontNames = XListFonts(QX11Info::display(), (char*)fontName.toLatin1().constData(), 32768, &count);
    if (fontNames) XFreeFontNames(fontNames);

    return count != 0;
}

QString QFont::lastResortFont() const
{
    static QString last;

    // already found
    if (! last.isNull())
        return last;

    int i = 0;
    const char* f;

    while ((f = tryFonts[i])) {
        last = QString::fromLatin1(f);

        if (fontExists(last))
            return last;

        i++;
    }

#if defined(CHECK_NULL)
    qFatal("QFontPrivate::lastResortFont: Cannot find any reasonable font");
#endif
    return last;
}

QT_END_NAMESPACE