Changeset 238363 in webkit

Timestamp:

Nov 18, 2018 9:26:15 AM (5 years ago)

Author:

commit-queue@webkit.org

Message:

HarfBuzzFace::CacheEntry should use 32-bit values in its HashMap
​https://bugs.webkit.org/show_bug.cgi?id=191825

Patch by Zan Dobersek <​zdobersek@igalia.com> on 2018-11-18
Reviewed by Michael Catanzaro.

The HashMap-based glyph cache contained in HarfBuzzFace::CacheEntry
objects is used to map given Unicode codepoints to corresponding
glyph indices (which occurs in the harfBuzzGetGlyph() function that's
invoked by HarfBuzz).

The 16-bit unsigned integer as the map's value type is not enough here
when the glyph index mapping is done through Freetype -- its API returns
32-bit glyph indices, and Cairo assigns this value to the 64-bit
unsigned index variable in the cairo_glyph_t struct. The value type is
thus bumped to 32 bits to match the unsigned type size of the index's
origin.

• platform/graphics/harfbuzz/HarfBuzzFace.h:
• platform/graphics/harfbuzz/HarfBuzzFaceCairo.cpp:

Location:

trunk/Source/WebCore

Files:

• ChangeLog (modified) (1 diff)
• platform/graphics/harfbuzz/HarfBuzzFace.h (modified) (1 diff)
• platform/graphics/harfbuzz/HarfBuzzFaceCairo.cpp (modified) (1 diff)

trunk/Source/WebCore/ChangeLog

@@ +1 @@
+2018-11-18  Zan Dobersek  <zdobersek@igalia.com>
+
+        HarfBuzzFace::CacheEntry should use 32-bit values in its HashMap
+        https://bugs.webkit.org/show_bug.cgi?id=191825
+
+        Reviewed by Michael Catanzaro.
+
+        The HashMap-based glyph cache contained in HarfBuzzFace::CacheEntry
+        objects is used to map given Unicode codepoints to corresponding
+        glyph indices (which occurs in the harfBuzzGetGlyph() function that's
+        invoked by HarfBuzz).
+
+        The 16-bit unsigned integer as the map's value type is not enough here
+        when the glyph index mapping is done through Freetype -- its API returns
+        32-bit glyph indices, and Cairo assigns this value to the 64-bit
+        unsigned index variable in the cairo_glyph_t struct. The value type is
+        thus bumped to 32 bits to match the unsigned type size of the index's
+        origin.
+
+        * platform/graphics/harfbuzz/HarfBuzzFace.h:
+        * platform/graphics/harfbuzz/HarfBuzzFaceCairo.cpp:
+
 2018-11-17  Wenson Hsieh  <wenson_hsieh@apple.com>
 

trunk/Source/WebCore/platform/graphics/harfbuzz/HarfBuzzFace.h

@@ -61 +61 @@
     class CacheEntry : public RefCounted<CacheEntry> {
     public:
-        using GlyphCache = HashMap<uint32_t, uint16_t>;
+        using GlyphCache = HashMap<uint32_t, uint32_t>;
 
         static Ref<CacheEntry> create(hb_face_t* face)

trunk/Source/WebCore/platform/graphics/harfbuzz/HarfBuzzFaceCairo.cpp

@@ -51 +51 @@
 
 struct HarfBuzzFontData {
-    WTF::HashMap<uint32_t, uint16_t>& glyphCacheForFaceCacheEntry;
+    WTF::HashMap<uint32_t, uint32_t>& glyphCacheForFaceCacheEntry;
     RefPtr<cairo_scaled_font_t> cairoScaledFont;
 };