Changeset 147681 in webkit

Timestamp:

Apr 4, 2013 4:56:13 PM (11 years ago)

Author:

Christophe Dumez

Message:

Regression(r147639) Causes assertion hit in HashTable
​https://bugs.webkit.org/show_bug.cgi?id=113954

Reviewed by Benjamin Poulain.

Lookup the key in the hash table again after the recursive call to
getCachedFontPlatformData() as it may have altered the hash map and
invalidated the previous iterator we had.

No new tests, covered by existing tests.

• platform/graphics/FontCache.cpp:

(WebCore::FontCache::getCachedFontPlatformData):

Location:

trunk/Source/WebCore

Files:

• ChangeLog (modified) (1 diff)
• platform/graphics/FontCache.cpp (modified) (2 diffs)

trunk/Source/WebCore/ChangeLog

@@ +1 @@
+2013-04-04  Christophe Dumez  <ch.dumez@sisa.samsung.com>
+
+        Regression(r147639) Causes assertion hit in HashTable
+        https://bugs.webkit.org/show_bug.cgi?id=113954
+
+        Reviewed by Benjamin Poulain.
+
+        Lookup the key in the hash table again after the recursive call to
+        getCachedFontPlatformData() as it may have altered the hash map and
+        invalidated the previous iterator we had.
+
+        No new tests, covered by existing tests.
+
+        * platform/graphics/FontCache.cpp:
+        (WebCore::FontCache::getCachedFontPlatformData):
+
 2013-04-04  Eric Carlson  <eric.carlson@apple.com>
 

trunk/Source/WebCore/platform/graphics/FontCache.cpp

@@ -203 +203 @@
 
     FontPlatformDataCache::AddResult result = gFontPlatformDataCache->add(key, nullptr);
+    FontPlatformDataCache::iterator it = result.iterator;
     if (result.isNewEntry) {
-        result.iterator->value = createFontPlatformData(fontDescription, familyName);
-
-        if (!result.iterator->value && !checkingAlternateName) {
+        it->value = createFontPlatformData(fontDescription, familyName);
+
+        if (!it->value && !checkingAlternateName) {
             // We were unable to find a font.  We have a small set of fonts that we alias to other names,
             // e.g., Arial/Helvetica, Courier/Courier New, etc.  Try looking up the font under the aliased name.
@@ -212 +213 @@
             if (!alternateName.isEmpty()) {
                 FontPlatformData* fontPlatformDataForAlternateName = getCachedFontPlatformData(fontDescription, alternateName, true);
+                // Lookup the key in the hash table again as the previous iterator may have
+                // been invalidated by the recursive call to getCachedFontPlatformData().
+                it = gFontPlatformDataCache->find(key);
+                ASSERT(it != gFontPlatformDataCache->end());
                 if (fontPlatformDataForAlternateName)
-                    result.iterator->value = adoptPtr(new FontPlatformData(*fontPlatformDataForAlternateName));
+                    it->value = adoptPtr(new FontPlatformData(*fontPlatformDataForAlternateName));
             }
         }
     }
 
-    return result.iterator->value.get();
+    return it->value.get();
 }