Changeset 194839 in webkit for trunk/Source/WebCore/css/CSSFontFaceSource.cpp

Timestamp:

Jan 10, 2016, 9:55:14 PM (9 years ago)

Author:

[email protected]

Message:

[SVG -> OTF Converter] Parsing failures cause use of incomplete fonts
​https://bugs.webkit.org/show_bug.cgi?id=152772
<rdar://problem/24043104>

Reviewed by Simon Fraser.

Source/WebCore:

Originally, if we fail to parse a glyph, we would simply skip the glyph. However, this means that
we will create an incomplete font without all the necessary glyphs. This causes very distressing
text where all the occurances of a particular letter are missing. Instead, we should treat the
entire font as invalid.

Test: fast/text/svg-font-invalid-glyph-path-failure.html

• css/CSSFontFaceSource.cpp:

(WebCore::CSSFontFaceSource::font):

• loader/cache/CachedSVGFont.cpp:

(WebCore::CachedSVGFont::ensureCustomFontData):

• svg/SVGToOTFFontConversion.cpp:

(WebCore::SVGToOTFFontConverter::error):
(WebCore::SVGToOTFFontConverter::transcodeGlyphPaths):
(WebCore::SVGToOTFFontConverter::processGlyphElement):
(WebCore::convertSVGToOTFFont):

• svg/SVGToOTFFontConversion.h:

LayoutTests:

Make sure the font renders as if its invalid.

• fast/text/resources/bustedfont.svg: Added.
• fast/text/svg-font-invalid-glyph-path-failure-expected.html: Added.
• fast/text/svg-font-invalid-glyph-path-failure.html: Added.

File:

• trunk/Source/WebCore/css/CSSFontFaceSource.cpp (modified) (1 diff)

trunk/Source/WebCore/css/CSSFontFaceSource.cpp

@@ -145 +145 @@
                 // FIXME: Re-run this when script modifies the element or any of its descendents
                 // FIXME: We might have already converted this font. Make existing conversions discoverable.
-                Vector<char> otfFont = convertSVGToOTFFont(fontElement);
-                m_generatedOTFBuffer = SharedBuffer::adoptVector(otfFont);
+                if (auto otfFont = convertSVGToOTFFont(fontElement))
+                    m_generatedOTFBuffer = SharedBuffer::adoptVector(otfFont.value());
                 if (!m_generatedOTFBuffer)
                     return nullptr;