linux: Make PlatformFontPango handle family lists.

A PangoFontDescription can hold a comma-separated list of
font family names (and we currently use lists for Chrome
OS), but PlatformFontPango was just passing the whole string
to FontConfig.  This change makes us first split the family
on commas and then pass the resulting values to FontConfig.

BUG=107389,109961
TEST=manual: tested that we use Chrome Droid Sans on Chrome OS instead of falling back to sans all the time


Review URL: http://codereview.chromium.org/9288009

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@119090 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 23 insertions, 28 deletions

diff --git a/ui/gfx/platform_font_pango.cc b/ui/gfx/platform_font_pango.cc
index 9ce18d1..5037829 100644
--- a/ui/gfx/platform_font_pango.cc
+++ b/ui/gfx/platform_font_pango.cc
@@ -12,6 +12,7 @@
 
 #include "base/logging.h"
 #include "base/string_piece.h"
+#include "base/string_split.h"
 #include "base/utf_string_conversions.h"
 #include "grit/app_locale_settings.h"
 #include "third_party/skia/include/core/SkTypeface.h"
@@ -63,38 +64,34 @@ PangoFontMetrics* GetPangoFontMetrics(PangoFontDescription* desc) {
   }
 }
 
-// Find the best match font for |family_name| in the same way as Skia
-// to make sure CreateFont() successfully creates a default font.  In
-// Skia, it only checks the best match font.  If it failed to find
-// one, SkTypeface will be NULL for that font family.  It eventually
-// causes a segfault.  For example, family_name = "Sans" and system
-// may have various fonts.  The first font family in FcPattern will be
-// "DejaVu Sans" but a font family returned by FcFontMatch will be "VL
-// PGothic".  In this case, SkTypeface for "Sans" returns NULL even if
-// the system has a font for "Sans" font family.  See FontMatch() in
-// skia/ports/SkFontHost_fontconfig.cpp for more detail.
-std::string FindBestMatchFontFamilyName(const char* family_name) {
+// Returns the available font family that best (in FontConfig's eyes) matches
+// the supplied list of family names.
+std::string FindBestMatchFontFamilyName(
+    const std::vector<std::string>& family_names) {
   FcPattern* pattern = FcPatternCreate();
-  FcValue fcvalue;
-  fcvalue.type = FcTypeString;
-  char* family_name_copy = strdup(family_name);
-  fcvalue.u.s = reinterpret_cast<FcChar8*>(family_name_copy);
-  FcPatternAdd(pattern, FC_FAMILY, fcvalue, 0);
+  for (std::vector<std::string>::const_iterator it = family_names.begin();
+       it != family_names.end(); ++it) {
+    FcValue fcvalue;
+    fcvalue.type = FcTypeString;
+    fcvalue.u.s = reinterpret_cast<const FcChar8*>(it->c_str());
+    FcPatternAdd(pattern, FC_FAMILY, fcvalue, FcTrue /* append */);
+  }
+
   FcConfigSubstitute(0, pattern, FcMatchPattern);
   FcDefaultSubstitute(pattern);
   FcResult result;
   FcPattern* match = FcFontMatch(0, pattern, &result);
-  DCHECK(match) << "Could not find font: " << family_name;
-  FcChar8* match_family;
+  DCHECK(match) << "Could not find font";
+  FcChar8* match_family = NULL;
   FcPatternGetString(match, FC_FAMILY, 0, &match_family);
-
   std::string font_family(reinterpret_cast<char*>(match_family));
-  FcPatternDestroy(match);
   FcPatternDestroy(pattern);
-  free(family_name_copy);
+  FcPatternDestroy(match);
   return font_family;
 }
 
+// Returns a Pango font description (suitable for parsing by
+// pango_font_description_from_string()) for the default UI font.
 std::string GetDefaultFont() {
 #if defined(USE_WAYLAND) || !defined(TOOLKIT_USES_GTK)
 #if defined(OS_CHROMEOS)
@@ -149,14 +146,12 @@ PlatformFontPango::PlatformFontPango(const Font& other) {
 }
 
 PlatformFontPango::PlatformFontPango(NativeFont native_font) {
-  const char* family_name = pango_font_description_get_family(native_font);
-
-  // Find best match font for |family_name| to make sure we can get
-  // a SkTypeface for the default font.
-  // TODO(agl): remove this.
-  std::string font_family = FindBestMatchFontFamilyName(family_name);
-
+  std::vector<std::string> family_names;
+  base::SplitString(pango_font_description_get_family(native_font), ',',
+                    &family_names);
+  std::string font_family = FindBestMatchFontFamilyName(family_names);
   InitWithNameAndSize(font_family, gfx::GetPangoFontSizeInPixels(native_font));
+
   int style = 0;
   if (pango_font_description_get_weight(native_font) == PANGO_WEIGHT_BOLD) {
     // TODO(davemoore) What should we do about other weights? We currently