Linux: Add support for chrooted renderers.

skia/ext/SkFontHost_fontconfig_direct.h

+/* libs/graphics/ports/SkFontHost_fontconfig_direct.h
+**
+** Copyright 2009, Google Inc.
+**
+** Licensed under the Apache License, Version 2.0 (the "License");
+** you may not use this file except in compliance with the License.
+** You may obtain a copy of the License at
+**
+**     http://www.apache.org/licenses/LICENSE-2.0
+**
+** Unless required by applicable law or agreed to in writing, software
+** distributed under the License is distributed on an "AS IS" BASIS,
+** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+** See the License for the specific language governing permissions and
+** limitations under the License.
+*/
+
+#ifndef FontConfigDirect_DEFINED
+#define FontConfigDirect_DEFINED
+
+#include <map>
+#include <string>
+
+#include "SkThread.h"
+#include "SkFontHost_fontconfig_impl.h"
+
+class FontConfigDirect : public FontConfigInterface {
+  public:
+    FontConfigDirect();
+
+    // FontConfigInterface implementation. Thread safe.
+    virtual bool Match(std::string* result_family, unsigned* result_fileid,
+                       bool fileid_valid, unsigned fileid,
+                       const std::string& family, int is_bold, int is_italic);
+    virtual int Open(unsigned fileid);
+
+  private:
+    SkMutex mutex_;
+    std::map<unsigned, std::string> fileid_to_filename_;
+    std::map<std::string, unsigned> filename_to_fileid_;
+    unsigned next_file_id_;
+};
+
+#endif  // FontConfigDirect_DEFINED