Adding upstream version 4:24.2.0.upstream/4%24.2.0

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 526 insertions, 0 deletions

diff --git a/vcl/unx/generic/gdi/cairotextrender.cxx b/vcl/unx/generic/gdi/cairotextrender.cxx
new file mode 100644
index 0000000000..7e7ce9ca70
--- /dev/null
+++ b/vcl/unx/generic/gdi/cairotextrender.cxx
@@ -0,0 +1,526 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include <sal/config.h>
+
+#include <comphelper/scopeguard.hxx>
+#include <unx/cairotextrender.hxx>
+#include <unx/fc_fontoptions.hxx>
+#include <unx/freetype_glyphcache.hxx>
+#include <unx/gendata.hxx>
+#include <headless/CairoCommon.hxx>
+#include <vcl/svapp.hxx>
+#include <sallayout.hxx>
+#include <salinst.hxx>
+
+#include <cairo.h>
+#include <cairo-ft.h>
+#if defined(CAIRO_HAS_SVG_SURFACE)
+#include <cairo-svg.h>
+#elif defined(CAIRO_HAS_PDF_SURFACE)
+#include <cairo-pdf.h>
+#endif
+
+#include <deque>
+
+namespace {
+
+typedef struct FT_FaceRec_* FT_Face;
+
+class CairoFontsCache
+{
+public:
+    struct CacheId
+    {
+        FT_Face maFace;
+        const FontConfigFontOptions *mpOptions;
+        bool mbEmbolden;
+        bool mbVerticalMetrics;
+        bool operator ==(const CacheId& rOther) const
+        {
+            return maFace == rOther.maFace &&
+                mpOptions == rOther.mpOptions &&
+                mbEmbolden == rOther.mbEmbolden &&
+                mbVerticalMetrics == rOther.mbVerticalMetrics;
+        }
+    };
+
+private:
+    typedef         std::deque< std::pair<cairo_font_face_t*, CacheId> > LRUFonts;
+    static LRUFonts maLRUFonts;
+public:
+                                CairoFontsCache() = delete;
+
+    static void                 CacheFont(cairo_font_face_t* pFont, const CacheId &rId);
+    static cairo_font_face_t*   FindCachedFont(const CacheId &rId);
+};
+
+CairoFontsCache::LRUFonts CairoFontsCache::maLRUFonts;
+
+void CairoFontsCache::CacheFont(cairo_font_face_t* pFont, const CairoFontsCache::CacheId &rId)
+{
+    maLRUFonts.push_front( std::pair<cairo_font_face_t*, CairoFontsCache::CacheId>(pFont, rId) );
+    if (maLRUFonts.size() > 8)
+    {
+        cairo_font_face_destroy(maLRUFonts.back().first);
+        maLRUFonts.pop_back();
+    }
+}
+
+cairo_font_face_t* CairoFontsCache::FindCachedFont(const CairoFontsCache::CacheId &rId)
+{
+    auto aI = std::find_if(maLRUFonts.begin(), maLRUFonts.end(),
+        [&rId](const LRUFonts::value_type& rFont) { return rFont.second == rId; });
+    if (aI != maLRUFonts.end())
+        return aI->first;
+    return nullptr;
+}
+
+}
+
+namespace
+{
+    bool hasRotation(int nRotation)
+    {
+      return nRotation != 0;
+    }
+
+    double toRadian(Degree10 nDegree10th)
+    {
+        return toRadians(3600_deg10 - nDegree10th);
+    }
+
+    cairo_t* syncCairoContext(cairo_t* cr)
+    {
+        //rhbz#1283420 tdf#117413 bodge to force a read from the underlying surface which has
+        //the side effect of making the mysterious xrender related problem go away
+        cairo_surface_t *target = cairo_get_target(cr);
+        if (cairo_surface_get_type(target) == CAIRO_SURFACE_TYPE_XLIB)
+        {
+            cairo_surface_t *throw_away = cairo_surface_create_similar(target, cairo_surface_get_content(target), 1, 1);
+            cairo_t *force_read_cr = cairo_create(throw_away);
+            cairo_set_source_surface(force_read_cr, target, 0, 0);
+            cairo_paint(force_read_cr);
+            cairo_destroy(force_read_cr);
+            cairo_surface_destroy(throw_away);
+        }
+        return cr;
+    }
+}
+
+#if defined(FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION)
+extern "C"
+{
+    __attribute__((weak)) void __lsan_disable();
+    __attribute__((weak)) void __lsan_enable();
+}
+#endif
+
+namespace {
+    struct CairoFontOptions
+    {
+        // https://gitlab.freedesktop.org/cairo/cairo/-/merge_requests/235
+        // I don't want to have CAIRO_ROUND_GLYPH_POS_ON set in the cairo
+        // surfaces font_options, but that's private, so tricky to achieve
+        cairo_font_options_t* mpRoundGlyphPosOffOptions;
+
+        CairoFontOptions()
+        {
+            // https://gitlab.freedesktop.org/cairo/cairo/-/merge_requests/235
+            // I don't want to have CAIRO_ROUND_GLYPH_POS_ON set in the cairo surfaces
+            // font_options when trying subpixel rendering, but that's a private
+            // feature of cairo_font_options_t, so tricky to achieve. Hack this by
+            // getting the font options of a backend known to set this private feature
+            // to CAIRO_ROUND_GLYPH_POS_OFF and then set to defaults the public
+            // features and the result can be merged with new font options to set
+            // CAIRO_ROUND_GLYPH_POS_OFF in those
+            mpRoundGlyphPosOffOptions = cairo_font_options_create();
+#if defined(CAIRO_HAS_SVG_SURFACE)
+            // svg, pdf and ps backends have CAIRO_ROUND_GLYPH_POS_OFF by default
+            cairo_surface_t* hack = cairo_svg_surface_create(nullptr, 1, 1);
+#elif defined(CAIRO_HAS_PDF_SURFACE)
+            cairo_surface_t* hack = cairo_pdf_surface_create(nullptr, 1, 1);
+#endif
+            cairo_surface_get_font_options(hack, mpRoundGlyphPosOffOptions);
+            cairo_surface_destroy(hack);
+            cairo_font_options_set_antialias(mpRoundGlyphPosOffOptions, CAIRO_ANTIALIAS_DEFAULT);
+            cairo_font_options_set_subpixel_order(mpRoundGlyphPosOffOptions, CAIRO_SUBPIXEL_ORDER_DEFAULT);
+            cairo_font_options_set_hint_style(mpRoundGlyphPosOffOptions, CAIRO_HINT_STYLE_DEFAULT);
+            cairo_font_options_set_hint_metrics(mpRoundGlyphPosOffOptions, CAIRO_HINT_METRICS_DEFAULT);
+        }
+        ~CairoFontOptions()
+        {
+            cairo_font_options_destroy(mpRoundGlyphPosOffOptions);
+        }
+        static const cairo_font_options_t *get()
+        {
+            static CairoFontOptions opts;
+            return opts.mpRoundGlyphPosOffOptions;
+        }
+    };
+}
+
+CairoTextRender::CairoTextRender(CairoCommon& rCairoCommon)
+    : mrCairoCommon(rCairoCommon)
+{
+}
+
+CairoTextRender::~CairoTextRender()
+{
+}
+
+static void ApplyFont(cairo_t* cr, const CairoFontsCache::CacheId& rId, double nWidth, double nHeight, int nGlyphRotation,
+                      const GenericSalLayout& rLayout)
+{
+    cairo_font_face_t* font_face = CairoFontsCache::FindCachedFont(rId);
+    if (!font_face)
+    {
+        const FontConfigFontOptions *pOptions = rId.mpOptions;
+        FcPattern *pPattern = pOptions->GetPattern();
+        font_face = cairo_ft_font_face_create_for_pattern(pPattern);
+        CairoFontsCache::CacheFont(font_face, rId);
+    }
+    cairo_set_font_face(cr, font_face);
+
+    cairo_set_font_size(cr, nHeight);
+
+    cairo_matrix_t m;
+    cairo_matrix_init_identity(&m);
+
+    if (rLayout.GetOrientation())
+        cairo_matrix_rotate(&m, toRadian(rLayout.GetOrientation()));
+
+    cairo_matrix_scale(&m, nWidth, nHeight);
+
+    if (nGlyphRotation)
+        cairo_matrix_rotate(&m, toRadian(Degree10(nGlyphRotation * 900)));
+
+    const LogicalFontInstance& rInstance = rLayout.GetFont();
+    if (rInstance.NeedsArtificialItalic())
+    {
+        cairo_matrix_t shear;
+        cairo_matrix_init_identity(&shear);
+        shear.xy = -shear.xx * ARTIFICIAL_ITALIC_SKEW;
+        cairo_matrix_multiply(&m, &shear, &m);
+    }
+
+    cairo_set_font_matrix(cr, &m);
+}
+
+static CairoFontsCache::CacheId makeCacheId(const GenericSalLayout& rLayout)
+{
+    const FreetypeFontInstance& rInstance = static_cast<FreetypeFontInstance&>(rLayout.GetFont());
+    const FreetypeFont& rFont = rInstance.GetFreetypeFont();
+
+    FT_Face aFace = rFont.GetFtFace();
+    CairoFontsCache::CacheId aId;
+    aId.maFace = aFace;
+    aId.mpOptions = rFont.GetFontOptions();
+    aId.mbEmbolden = rInstance.NeedsArtificialBold();
+    aId.mbVerticalMetrics = false;
+
+    return aId;
+}
+
+void CairoTextRender::DrawTextLayout(const GenericSalLayout& rLayout, const SalGraphics& rGraphics)
+{
+    const LogicalFontInstance& rInstance = rLayout.GetFont();
+
+    const bool bSubpixelPositioning = rLayout.GetSubpixelPositioning();
+
+    /*
+     * It might be ideal to cache surface and cairo context between calls and
+     * only destroy it when the drawable changes, but to do that we need to at
+     * least change the SalFrame etc impls to dtor the SalGraphics *before* the
+     * destruction of the windows they reference
+    */
+    cairo_t *cr = syncCairoContext(getCairoContext());
+    if (!cr)
+    {
+        SAL_WARN("vcl", "no cairo context for text");
+        return;
+    }
+    comphelper::ScopeGuard releaseContext([this, cr]() { releaseCairoContext(cr); });
+
+    std::vector<cairo_glyph_t> cairo_glyphs;
+    std::vector<int> glyph_extrarotation;
+    cairo_glyphs.reserve( 256 );
+
+    double nSnapToSubPixelDiff = 0.0;
+    double nXScale, nYScale;
+    dl_cairo_surface_get_device_scale(cairo_get_target(cr), &nXScale, &nYScale);
+
+    basegfx::B2DPoint aPos;
+    const GlyphItem* pGlyph;
+    const GlyphItem* pPrevGlyph = nullptr;
+    int nStart = 0;
+    while (rLayout.GetNextGlyph(&pGlyph, aPos, nStart))
+    {
+        cairo_glyph_t aGlyph;
+        aGlyph.index = pGlyph->glyphId();
+        aGlyph.x = aPos.getX();
+        aGlyph.y = aPos.getY();
+
+        const bool bVertical = pGlyph->IsVertical();
+        glyph_extrarotation.push_back(bVertical ? 1 : 0);
+
+        if (bSubpixelPositioning)
+        {
+            // tdf#150507 like skia, even when subpixel rendering pixel, snap y
+            if (!bVertical)
+                aGlyph.y = std::floor(aGlyph.y + 0.5);
+            else
+                aGlyph.x = std::floor(aGlyph.x + 0.5);
+
+            // tdf#152094 snap to 1/4 of a pixel after a run of whitespace,
+            // probably a little dubious, but maybe worth a shot for lodpi
+            double& rGlyphDimension = !bVertical ? aGlyph.x : aGlyph.y;
+            const int nSubPixels = 4 * (!bVertical ? nXScale : nYScale);
+            if (pGlyph->IsSpacing())
+                nSnapToSubPixelDiff = 0;
+            else if (pPrevGlyph && pPrevGlyph->IsSpacing())
+            {
+                double nSnapToSubPixel = std::floor(rGlyphDimension * nSubPixels) / nSubPixels;
+                nSnapToSubPixelDiff = rGlyphDimension - nSnapToSubPixel;
+                rGlyphDimension = nSnapToSubPixel;
+            }
+            else
+                rGlyphDimension -= nSnapToSubPixelDiff;
+
+            pPrevGlyph = pGlyph;
+        }
+
+        cairo_glyphs.push_back(aGlyph);
+    }
+
+    const size_t nGlyphs = cairo_glyphs.size();
+    if (!nGlyphs)
+        return;
+
+    const vcl::font::FontSelectPattern& rFSD = rInstance.GetFontSelectPattern();
+    double nHeight = rFSD.mnHeight;
+    double nWidth = rFSD.mnWidth ? rFSD.mnWidth : nHeight;
+    if (nWidth == 0 || nHeight == 0)
+        return;
+
+    if (nHeight > SAL_MAX_UINT16)
+    {
+        // as seen with freetype 2.11.0, so cairo surface status is "fail"
+        // ("error occurred in libfreetype") and no further operations are
+        // executed, so this error then leads to later leaks
+        SAL_WARN("vcl", "rendering text would fail with height: " << nHeight);
+        return;
+    }
+
+#if defined(FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION)
+    if (nHeight > 8000)
+    {
+        SAL_WARN("vcl", "rendering text would use > 2G Memory: " << nHeight);
+        return;
+    }
+
+    if (nWidth > 2000)
+    {
+        SAL_WARN("vcl", "rendering text would use > 2G Memory: " << nWidth);
+        return;
+    }
+#endif
+
+    clipRegion(cr);
+
+    cairo_set_source_rgba(cr,
+        mnTextColor.GetRed()/255.0,
+        mnTextColor.GetGreen()/255.0,
+        mnTextColor.GetBlue()/255.0,
+        mnTextColor.GetAlpha()/255.0);
+
+    int nRatio = nWidth * 10 / nHeight;
+
+    // tdf#132112 excessive stretch of underbrace and overbrace can trigger freetype into an error, which propagates to cairo
+    // and once a cairo surface is in an error state, that cannot be cleared and all subsequent drawing fails, so bodge that
+    // with a high degree of stretch we draw the brace without stretch to a temp surface and stretch that to give a far
+    // poorer visual result, but one that can be rendered.
+    if (nGlyphs == 1 && nRatio > 100 && (cairo_glyphs[0].index == 974 || cairo_glyphs[0].index == 975) &&
+        rFSD.maTargetName == "OpenSymbol" && !glyph_extrarotation.back() && !rLayout.GetOrientation())
+    {
+        CairoFontsCache::CacheId aId = makeCacheId(rLayout);
+
+        ApplyFont(cr, aId, nWidth, nHeight, 0, rLayout);
+        cairo_text_extents_t stretched_extents;
+        cairo_glyph_extents(cr, cairo_glyphs.data(), nGlyphs, &stretched_extents);
+
+        ApplyFont(cr, aId, nHeight, nHeight, 0, rLayout);
+        cairo_text_extents_t unstretched_extents;
+        cairo_glyph_extents(cr, cairo_glyphs.data(), nGlyphs, &unstretched_extents);
+
+        cairo_surface_t *target = cairo_get_target(cr);
+        cairo_surface_t *temp_surface = cairo_surface_create_similar(target, cairo_surface_get_content(target),
+                                                                     unstretched_extents.width, unstretched_extents.height);
+        cairo_t *temp_cr = cairo_create(temp_surface);
+        cairo_glyph_t glyph;
+        glyph.x = -unstretched_extents.x_bearing;
+        glyph.y = -unstretched_extents.y_bearing;
+        glyph.index = cairo_glyphs[0].index;
+
+        ApplyFont(temp_cr, aId, nHeight, nHeight, 0, rLayout);
+
+        cairo_set_source_rgb(temp_cr,
+            mnTextColor.GetRed()/255.0,
+            mnTextColor.GetGreen()/255.0,
+            mnTextColor.GetBlue()/255.0);
+
+        cairo_show_glyphs(temp_cr, &glyph, 1);
+        cairo_destroy(temp_cr);
+
+        cairo_set_source_surface(cr, temp_surface, cairo_glyphs[0].x, cairo_glyphs[0].y + stretched_extents.y_bearing);
+
+        cairo_pattern_t* sourcepattern = cairo_get_source(cr);
+        cairo_matrix_t matrix;
+        cairo_pattern_get_matrix(sourcepattern, &matrix);
+        cairo_matrix_scale(&matrix, unstretched_extents.width / stretched_extents.width, 1);
+        cairo_pattern_set_matrix(sourcepattern, &matrix);
+
+        cairo_rectangle(cr, cairo_glyphs[0].x, cairo_glyphs[0].y + stretched_extents.y_bearing, stretched_extents.width, stretched_extents.height);
+        cairo_fill(cr);
+
+        cairo_surface_destroy(temp_surface);
+
+        return;
+    }
+
+    if (nRatio >= 5120)
+    {
+        // as seen with freetype 2.12.1, so cairo surface status is "fail"
+        SAL_WARN("vcl", "rendering text would fail with stretch of: " << nRatio / 10.0);
+        return;
+    }
+
+#if defined(FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION)
+    if (__lsan_disable)
+        __lsan_disable();
+#endif
+
+    const StyleSettings& rStyleSettings = Application::GetSettings().GetStyleSettings();
+    const bool bDisableAA = !rStyleSettings.GetUseFontAAFromSystem() && !rGraphics.getAntiAlias();
+    static bool bAllowDefaultHinting = getenv("SAL_ALLOW_DEFAULT_HINTING") != nullptr;
+
+    const cairo_font_options_t* pFontOptions = GetSalInstance()->GetCairoFontOptions();
+    if (pFontOptions || bDisableAA || bSubpixelPositioning)
+    {
+        cairo_hint_style_t eHintStyle = pFontOptions ? cairo_font_options_get_hint_style(pFontOptions) : CAIRO_HINT_STYLE_DEFAULT;
+        bool bAllowedHintStyle = !bSubpixelPositioning || bAllowDefaultHinting || (eHintStyle == CAIRO_HINT_STYLE_NONE || eHintStyle == CAIRO_HINT_STYLE_SLIGHT);
+
+        if (bDisableAA || !bAllowedHintStyle || bSubpixelPositioning)
+        {
+            // Disable font AA in case global AA setting is supposed to affect
+            // font rendering (not the default) and AA is disabled.
+            cairo_font_options_t* pOptions = pFontOptions ? cairo_font_options_copy(pFontOptions) : cairo_font_options_create();
+
+            if (bDisableAA)
+                cairo_font_options_set_antialias(pOptions, CAIRO_ANTIALIAS_NONE);
+            if (!bAllowedHintStyle)
+                cairo_font_options_set_hint_style(pOptions, CAIRO_HINT_STYLE_SLIGHT);
+            if (bSubpixelPositioning)
+            {
+                // Disable private CAIRO_ROUND_GLYPH_POS_ON by merging with
+                // font options known to have CAIRO_ROUND_GLYPH_POS_OFF
+                cairo_font_options_merge(pOptions, CairoFontOptions::get());
+
+                // a) tdf#153699 skip this with cairo 1.17.8 as it has a problem
+                // See: https://gitlab.freedesktop.org/cairo/cairo/-/issues/643
+                // b) tdf#152675 a similar report for cairo: 1.16.0-4ubuntu1,
+                // assume that everything <= 1.17.8 is unsafe to disable this
+                if (cairo_version() > CAIRO_VERSION_ENCODE(1, 17, 8))
+                    cairo_font_options_set_hint_metrics(pOptions, CAIRO_HINT_METRICS_OFF);
+            }
+            cairo_set_font_options(cr, pOptions);
+            cairo_font_options_destroy(pOptions);
+        }
+        else if (pFontOptions)
+            cairo_set_font_options(cr, pFontOptions);
+    }
+
+    CairoFontsCache::CacheId aId = makeCacheId(rLayout);
+
+    std::vector<int>::const_iterator aEnd = glyph_extrarotation.end();
+    std::vector<int>::const_iterator aStart = glyph_extrarotation.begin();
+    std::vector<int>::const_iterator aI = aStart;
+    while (aI != aEnd)
+    {
+        int nGlyphRotation = *aI;
+
+        std::vector<int>::const_iterator aNext = nGlyphRotation?(aI+1):std::find_if(aI+1, aEnd, hasRotation);
+
+        size_t nStartIndex = std::distance(aStart, aI);
+        size_t nLen = std::distance(aI, aNext);
+
+        aId.mbVerticalMetrics = nGlyphRotation != 0.0;
+
+        ApplyFont(cr, aId, nWidth, nHeight, nGlyphRotation, rLayout);
+
+        cairo_show_glyphs(cr, &cairo_glyphs[nStartIndex], nLen);
+        if (cairo_status(cr) != CAIRO_STATUS_SUCCESS)
+        {
+            SAL_WARN("vcl", "rendering text failed with stretch ratio of: " << nRatio << ", " << cairo_status_to_string(cairo_status(cr)));
+        }
+
+#if OSL_DEBUG_LEVEL > 2
+        //draw origin
+        cairo_save (cr);
+        cairo_rectangle (cr, cairo_glyphs[nStartIndex].x, cairo_glyphs[nStartIndex].y, 5, 5);
+        cairo_set_source_rgba (cr, 1, 0, 0, 0.80);
+        cairo_fill (cr);
+        cairo_restore (cr);
+#endif
+
+        aI = aNext;
+    }
+
+#if defined(FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION)
+    if (__lsan_enable)
+        __lsan_enable();
+#endif
+}
+
+cairo_t* CairoTextRender::getCairoContext()
+{
+    // Note that cairo_set_antialias (bAntiAlias property) doesn't affect cairo
+    // text rendering.  That's affected by cairo_font_options_set_antialias instead.
+    return mrCairoCommon.getCairoContext(/*bXorModeAllowed*/false, /*bAntiAlias*/true);
+}
+
+void CairoTextRender::clipRegion(cairo_t* cr)
+{
+    mrCairoCommon.clipRegion(cr);
+}
+
+void CairoTextRender::releaseCairoContext(cairo_t* cr)
+{
+    mrCairoCommon.releaseCairoContext(cr, /*bXorModeAllowed*/false, basegfx::B2DRange());
+}
+
+void FontConfigFontOptions::cairo_font_options_substitute(FcPattern* pPattern)
+{
+    const cairo_font_options_t* pFontOptions = GetSalInstance()->GetCairoFontOptions();
+    if( !pFontOptions )
+        return;
+    cairo_ft_font_options_substitute(pFontOptions, pPattern);
+}
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */