Backed out changeset 52b6489a3140 (bug 653100) because of reftest oranges.

gfx/thebes/gfxFont.cpp

@@ -359,6 +359,25 @@ gfxFontEntry::ShareFontTableAndGetBlob(PRUint32 aTag,
     return entry->ShareTableAndGetBlob(*aBuffer, &mFontTableCache);
 }
 
+void
+gfxFontEntry::PreloadFontTable(PRUint32 aTag, FallibleTArray<PRUint8>& aTable)
+{
+    if (!mFontTableCache.IsInitialized()) {
+        // This is intended for use with downloaded fonts, to cache the layout
+        // tables for harfbuzz, so initialize the cache for 3 entries to allow
+        // for GDEF/GSUB/GPOS.
+        mFontTableCache.Init(3);
+    }
+
+    FontTableHashEntry *entry = mFontTableCache.PutEntry(aTag);
+    if (NS_UNLIKELY(!entry)) { // OOM
+        return;
+    }
+
+    // adopts elements of aTable
+    entry->SaveTable(aTable);
+}
+
 //////////////////////////////////////////////////////////////////////////////
 //
 // class gfxFontFamily

gfx/thebes/gfxFont.h

@@ -295,6 +295,11 @@ public:
     hb_blob_t *ShareFontTableAndGetBlob(PRUint32 aTag,
                                         FallibleTArray<PRUint8>* aTable);
 
+    // Preload a font table into the cache (used to store layout tables for
+    // harfbuzz, when they will be stripped from the actual sfnt being
+    // passed to platform font APIs for rasterization)
+    void PreloadFontTable(PRUint32 aTag, FallibleTArray<PRUint8>& aTable);
+
     nsString         mName;
 
     PRPackedBool     mItalic      : 1;

gfx/thebes/gfxUserFontSet.cpp

@@ -372,6 +372,91 @@ SanitizeOpenTypeData(const PRUint8* aData, PRUint32 aLength,
     }
 }
 
+// Find the GDEF, GSUB, GPOS tables in aFontData (if present)
+// and cache copies in the given font entry.
+// The sfnt table directory has already been accepted by the OTS
+// sanitizer before this is called, so we can assume entries are valid.
+//
+// This is a temporary workaround until OTS has full support for the
+// G*** tables, so that they can safely be left in the main font.
+// When http://code.google.com/p/chromium/issues/detail?id=27131 gets fixed,
+// we should remove this hack.
+static void
+CacheLayoutTablesFromSFNT(const PRUint8* aFontData, PRUint32 aLength,
+                          gfxFontEntry* aFontEntry)
+{
+    const SFNTHeader *sfntHeader = reinterpret_cast<const SFNTHeader*>(aFontData);
+    PRUint16 numTables = sfntHeader->numTables;
+    
+    // table directory entries begin immediately following SFNT header
+    const TableDirEntry *dirEntry = 
+        reinterpret_cast<const TableDirEntry*>(aFontData + sizeof(SFNTHeader));
+
+    while (numTables-- > 0) {
+        switch (dirEntry->tag) {
+        case TRUETYPE_TAG('G','D','E','F'):
+        case TRUETYPE_TAG('G','P','O','S'):
+        case TRUETYPE_TAG('G','S','U','B'): {
+                FallibleTArray<PRUint8> buffer;
+                if (!buffer.AppendElements(aFontData + dirEntry->offset,
+                                           dirEntry->length)) {
+                    NS_WARNING("failed to cache font table - out of memory?");
+                    break;
+                }
+                aFontEntry->PreloadFontTable(dirEntry->tag, buffer);
+            }
+            break;
+
+        default:
+            if (dirEntry->tag > TRUETYPE_TAG('G','S','U','B')) {
+                // directory entries are required to be sorted,
+                // so we can terminate as soon as we find a tag > 'GSUB'
+                numTables = 0;
+            }
+            break;
+        }
+        ++dirEntry;
+    }
+}
+
+// OTS drops the OT Layout tables when decoding a WOFF file, so retrieve them
+// separately and cache them (unchecked) in the font entry; harfbuzz will
+// sanitize them when it needs to use them.
+static void
+PreloadTableFromWOFF(const PRUint8* aFontData, PRUint32 aLength,
+                     PRUint32 aTableTag, gfxFontEntry* aFontEntry)
+{
+    PRUint32 status = eWOFF_ok;
+    PRUint32 len = woffGetTableSize(aFontData, aLength, aTableTag, &status);
+    if (WOFF_SUCCESS(status) && len > 0) {
+        FallibleTArray<PRUint8> buffer;
+        if (!buffer.AppendElements(len)) {
+            NS_WARNING("failed to cache font table - out of memory?");
+            return;
+        }
+        woffGetTableToBuffer(aFontData, aLength, aTableTag,
+                             buffer.Elements(), buffer.Length(),
+                             &len, &status);
+        if (WOFF_FAILURE(status)) {
+            NS_WARNING("failed to cache font table - WOFF decoding error?");
+            return;
+        }
+        aFontEntry->PreloadFontTable(aTableTag, buffer);
+    }
+}
+
+static void
+CacheLayoutTablesFromWOFF(const PRUint8* aFontData, PRUint32 aLength,
+                          gfxFontEntry* aFontEntry)
+{
+    PreloadTableFromWOFF(aFontData, aLength, TRUETYPE_TAG('G','D','E','F'),
+                         aFontEntry);
+    PreloadTableFromWOFF(aFontData, aLength, TRUETYPE_TAG('G','P','O','S'),
+                         aFontEntry);
+    PreloadTableFromWOFF(aFontData, aLength, TRUETYPE_TAG('G','S','U','B'),
+                         aFontEntry);
+}
+
 // This is called when a font download finishes.
 // Ownership of aFontData passes in here, and the font set must
 // ensure that it is eventually deleted via NS_Free().
@@ -411,7 +496,24 @@ gfxUserFontSet::OnLoadComplete(gfxProxyFontEntry *aProxy,
                 fe = gfxPlatform::GetPlatform()->MakePlatformFont(aProxy,
                                                                   saneData,
                                                                   saneLen);
-                if (!fe) {
+                if (fe) {
+                    // if aFontData includes OpenType layout tables, we need to
+                    // cache them in the font entry for harfbuzz to use,
+                    // as they will have been dropped from the sanitized sfnt
+                    // (temporary hack, see CacheLayoutTablesFromSFNT)
+                    switch (fontType) {
+                    case GFX_USERFONT_OPENTYPE:
+                        CacheLayoutTablesFromSFNT(aFontData, aLength, fe);
+                        break;
+
+                    case GFX_USERFONT_WOFF:
+                        CacheLayoutTablesFromWOFF(aFontData, aLength, fe);
+                        break;
+
+                    default:
+                        break;
+                    }
+                } else {
                     NS_WARNING("failed to make platform font from download");
                 }
             }