Changeset 57490 in webkit

Timestamp:

Apr 12, 2010 5:47:10 PM (14 years ago)

Author:

sfalken@apple.com

Message:

2010-04-12 Steve Falkenburg <​sfalken@apple.com>

Reviewed by Dan Bernstein.

WebKit should have more robust last-chance font fallback on Windows
​https://bugs.webkit.org/show_bug.cgi?id=37473
<rdar://problem/7789438> Crash in FontFallbackList::determinePitch
<rdar://problem/7233762> Crash in FontFallbackList::fontDataAt

Look harder for a suitable last-resort font. Previously, we checked for
"Times New Roman" followed by DEFAULT_GUI_FONT.

We now look for:

• Typically installed Unicode-capable fonts, in order of coverage
• DEFAULT_GUI_FONT
• SPI_GETNONCLIENTMETRICS fonts

• platform/graphics/win/FontCacheWin.cpp: (WebCore::FontCache::fontDataFromDescriptionAndLogFont): (WebCore::FontCache::getLastResortFallbackFont):

Location:

trunk/WebCore

Files:

• ChangeLog (modified) (1 diff)
• platform/graphics/win/FontCacheWin.cpp (modified) (1 diff)

trunk/WebCore/ChangeLog

@@ +1 @@
+2010-04-12  Steve Falkenburg  <sfalken@apple.com>
+
+        Reviewed by Dan Bernstein.
+
+        WebKit should have more robust last-chance font fallback on Windows
+        https://bugs.webkit.org/show_bug.cgi?id=37473
+        <rdar://problem/7789438> Crash in FontFallbackList::determinePitch
+        <rdar://problem/7233762> Crash in FontFallbackList::fontDataAt
+        
+        Look harder for a suitable last-resort font. Previously, we checked for
+        "Times New Roman" followed by DEFAULT_GUI_FONT.
+        
+        We now look for:
+        - Typically installed Unicode-capable fonts, in order of coverage
+        - DEFAULT_GUI_FONT
+        - SPI_GETNONCLIENTMETRICS fonts
+        
+        * platform/graphics/win/FontCacheWin.cpp:
+        (WebCore::FontCache::fontDataFromDescriptionAndLogFont):
+        (WebCore::FontCache::getLastResortFallbackFont):
+
 2010-04-12  David Hyatt  <hyatt@apple.com>
 

trunk/WebCore/platform/graphics/win/FontCacheWin.cpp

@@ -302 +302 @@
 }
 
+static SimpleFontData* fontDataFromDescriptionAndLogFont(FontCache* fontCache, const FontDescription& fontDescription, const LOGFONT& font)
+{
+    String fontFamily = String(font.lfFaceName, wcsnlen(font.lfFaceName, LF_FACESIZE));
+    return fontCache->getCachedFontData(fontDescription, fontFamily);
+}
+
 SimpleFontData* FontCache::getLastResortFallbackFont(const FontDescription& fontDescription)
 {
+    DEFINE_STATIC_LOCAL(SimpleFontData*, simpleFont, ());
+    if (simpleFont)
+        return simpleFont;
+
     // FIXME: Would be even better to somehow get the user's default font here.  For now we'll pick
     // the default that the user would get without changing any prefs.
-    static AtomicString timesStr("Times New Roman");
-    if (SimpleFontData* simpleFont = getCachedFontData(fontDescription, timesStr))
-        return simpleFont;
-
-    DEFINE_STATIC_LOCAL(String, defaultGUIFontFamily, ());
-    if (defaultGUIFontFamily.isEmpty()) {
-        HFONT defaultGUIFont = static_cast<HFONT>(GetStockObject(DEFAULT_GUI_FONT));
-        LOGFONT logFont;
-        GetObject(defaultGUIFont, sizeof(logFont), &logFont);
-        defaultGUIFontFamily = String(logFont.lfFaceName, wcsnlen(logFont.lfFaceName, LF_FACESIZE));
-    }
-    return getCachedFontData(fontDescription, defaultGUIFontFamily);
+
+    // Search all typical Windows-installed full Unicode fonts.
+    // Sorted by most to least glyphs according to http://en.wikipedia.org/wiki/Unicode_typefaces
+    // Start with Times New Roman also since it is the default if the user doesn't change prefs.
+    static AtomicString fallbackFonts[] = {
+        AtomicString("Times New Roman"),
+        AtomicString("Microsoft Sans Serif"),
+        AtomicString("Tahoma"),
+        AtomicString("Lucida Sans Unicode"),
+        AtomicString("Arial")
+    };
+    for (int i = 0; i < ARRAYSIZE(fallbackFonts); ++i) {
+        if (simpleFont = getCachedFontData(fontDescription, fallbackFonts[i]))
+            return simpleFont;
+    }
+
+    // Fall back to the DEFAULT_GUI_FONT if no known Unicode fonts are available.
+    if (HFONT defaultGUIFont = static_cast<HFONT>(GetStockObject(DEFAULT_GUI_FONT))) {
+        LOGFONT defaultGUILogFont;
+        GetObject(defaultGUIFont, sizeof(defaultGUILogFont), &defaultGUILogFont);
+        if (simpleFont = fontDataFromDescriptionAndLogFont(this, fontDescription, defaultGUILogFont))
+            return simpleFont;
+    }
+
+    // Fall back to Non-client metrics fonts.
+    NONCLIENTMETRICS nonClientMetrics = {0};
+    nonClientMetrics.cbSize = sizeof(nonClientMetrics);
+    if (SystemParametersInfo(SPI_GETNONCLIENTMETRICS, sizeof(nonClientMetrics), &nonClientMetrics, 0)) {
+        if (simpleFont = fontDataFromDescriptionAndLogFont(this, fontDescription, nonClientMetrics.lfMessageFont))
+            return simpleFont;
+        if (simpleFont = fontDataFromDescriptionAndLogFont(this, fontDescription, nonClientMetrics.lfMenuFont))
+            return simpleFont;
+        if (simpleFont = fontDataFromDescriptionAndLogFont(this, fontDescription, nonClientMetrics.lfStatusFont))
+            return simpleFont;
+        if (simpleFont = fontDataFromDescriptionAndLogFont(this, fontDescription, nonClientMetrics.lfCaptionFont))
+            return simpleFont;
+        if (simpleFont = fontDataFromDescriptionAndLogFont(this, fontDescription, nonClientMetrics.lfSmCaptionFont))
+            return simpleFont;
+    }
+    
+    ASSERT_NOT_REACHED();
+    return 0;
 }