chrome/browser/ui/webui/fileicon_source.h

   1 // Copyright (c) 2012 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_BROWSER_UI_WEBUI_FILEICON_SOURCE_H_
   6 #define CHROME_BROWSER_UI_WEBUI_FILEICON_SOURCE_H_
   7
   8 #include <string>
   9
  10 #include "base/files/file_path.h"
  11 #include "base/task/cancelable_task_tracker.h"
  12 #include "chrome/browser/icon_manager.h"
  13 #include "content/public/browser/url_data_source.h"
  14
  15 namespace gfx {
  16 class Image;
  17 }
  18
  19 // FileIconSource is the gateway between network-level chrome:
  20 // requests for favicons and the history backend that serves these.
  21 class FileIconSource : public content::URLDataSource {
  22  public:
  23   explicit FileIconSource();
  24
  25   // content::URLDataSource implementation.
  26   std::string GetSource() const override;
  27   void StartDataRequest(
  28       const std::string& path,
  29       int render_process_id,
  30       int render_frame_id,
  31       const content::URLDataSource::GotDataCallback& callback) override;
  32   std::string GetMimeType(const std::string&) const override;
  33
  34  protected:
  35   ~FileIconSource() override;
  36
  37   // Once the |path| and |icon_size| has been determined from the request, this
  38   // function is called to perform the actual fetch. Declared as virtual for
  39   // testing.
  40   virtual void FetchFileIcon(
  41       const base::FilePath& path,
  42       float scale_factor,
  43       IconLoader::IconSize icon_size,
  44       const content::URLDataSource::GotDataCallback& callback);
  45
  46  private:
  47   // Contains the necessary information for completing an icon fetch request.
  48   struct IconRequestDetails {
  49     IconRequestDetails();
  50     ~IconRequestDetails();
  51
  52     // The callback to run with the response.
  53     content::URLDataSource::GotDataCallback callback;
  54
  55     // The requested scale factor to respond with.
  56     float scale_factor;
  57   };
  58
  59   // Called when favicon data is available from the history backend.
  60   void OnFileIconDataAvailable(const IconRequestDetails& details,
  61                                gfx::Image* icon);
  62
  63   // Tracks tasks requesting file icons.
  64   base::CancelableTaskTracker cancelable_task_tracker_;
  65
  66   DISALLOW_COPY_AND_ASSIGN(FileIconSource);
  67 };
  68 #endif  // CHROME_BROWSER_UI_WEBUI_FILEICON_SOURCE_H_