chrome/utility/font_cache_handler_win.h

   1 // Copyright 2014 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef CHROME_UTILITY_FONT_CACHE_HANDLER_WIN_H_
   6 #define CHROME_UTILITY_FONT_CACHE_HANDLER_WIN_H_
   7
   8 #include "base/files/file_path.h"
   9 #include "base/memory/ref_counted.h"
  10 #include "base/memory/scoped_ptr.h"
  11 #include "chrome/utility/utility_message_handler.h"
  12
  13 namespace base {
  14 class TaskRunner;
  15 class Thread;
  16 }
  17
  18 // Handles requests to build a static direct write font cache. Must be invoked
  19 // in a non-sandboxed utility process. We build static font cache in utility
  20 // process as it is time consuming as well as crash prone thing. We already
  21 // have fall back of loading fonts from system fonts directory in place, so even
  22 // if we fail to build static cache in utility process, chrome will still
  23 // continue to run as is.
  24 class FontCacheHandler : public UtilityMessageHandler {
  25  public:
  26   FontCacheHandler();
  27   ~FontCacheHandler() override;
  28
  29   // IPC::Listener implementation
  30   bool OnMessageReceived(const IPC::Message& message) override;
  31
  32  private:
  33   void OnBuildFontCache(const base::FilePath& full_path);
  34   void StartBuildingFontCache(const base::FilePath& full_path);
  35   void Cleanup();
  36
  37   scoped_refptr<base::TaskRunner> utility_task_runner_;
  38
  39   // Thread that caching process runs on, while FontCacheHandler handles
  40   // messages from the browser process.
  41   scoped_ptr<base::Thread> cache_thread_;
  42
  43   DISALLOW_COPY_AND_ASSIGN(FontCacheHandler);
  44 };
  45
  46 #endif  // CHROME_UTILITY_FONT_CACHE_HANDLER_WIN_H_