content/browser/browser_url_handler.h

   1 // Copyright (c) 2011 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 // We handle some special browser-level URLs (like "about:version")
   6 // before they're handed to a renderer.  This lets us do the URL handling
   7 // on the browser side (which has access to more information than the
   8 // renderers do) as well as sidestep the risk of exposing data to
   9 // random web pages (because from the resource loader's perspective, these
  10 // URL schemes don't exist).
  11
  12 #ifndef CONTENT_BROWSER_BROWSER_URL_HANDLER_H_
  13 #define CONTENT_BROWSER_BROWSER_URL_HANDLER_H_
  14 #pragma once
  15
  16 #include <vector>
  17 #include <utility>
  18
  19 #include "base/gtest_prod_util.h"
  20 #include "base/memory/singleton.h"
  21
  22 class GURL;
  23
  24 namespace content {
  25 class BrowserContext;
  26 }
  27
  28 // BrowserURLHandler manages the list of all special URLs and manages
  29 // dispatching the URL handling to registered handlers.
  30 class BrowserURLHandler {
  31  public:
  32   // The type of functions that can process a URL.
  33   // If a handler handles |url|, it should :
  34   // - optionally modify |url| to the URL that should be sent to the renderer
  35   // If the URL is not handled by a handler, it should return false.
  36   typedef bool (*URLHandler)(GURL* url,
  37                              content::BrowserContext* browser_context);
  38
  39   // Returns the singleton instance.
  40   static BrowserURLHandler* GetInstance();
  41
  42   // RewriteURLIfNecessary gives all registered URLHandlers a shot at processing
  43   // the given URL, and modifies it in place.
  44   // If the original URL needs to be adjusted if the modified URL is redirected,
  45   // this function sets |reverse_on_redirect| to true.
  46   void RewriteURLIfNecessary(GURL* url,
  47                              content::BrowserContext* browser_context,
  48                              bool* reverse_on_redirect);
  49
  50   // Reverses the rewriting that was done for |original| using the new |url|.
  51   bool ReverseURLRewrite(GURL* url, const GURL& original,
  52                          content::BrowserContext* browser_context);
  53
  54   // Add the specified handler pair to the list of URL handlers.
  55   void AddHandlerPair(URLHandler handler, URLHandler reverse_handler);
  56
  57   // Returns the null handler for use with |AddHandlerPair()|.
  58   static URLHandler null_handler();
  59
  60  private:
  61   // This object is a singleton:
  62   BrowserURLHandler();
  63   ~BrowserURLHandler();
  64   friend struct DefaultSingletonTraits<BrowserURLHandler>;
  65
  66   // The list of known URLHandlers, optionally with reverse-rewriters.
  67   typedef std::pair<URLHandler, URLHandler> HandlerPair;
  68   std::vector<HandlerPair> url_handlers_;
  69
  70   FRIEND_TEST_ALL_PREFIXES(BrowserURLHandlerTest, BasicRewriteAndReverse);
  71   FRIEND_TEST_ALL_PREFIXES(BrowserURLHandlerTest, NullHandlerReverse);
  72
  73   DISALLOW_COPY_AND_ASSIGN(BrowserURLHandler);
  74 };
  75
  76 #endif  // CONTENT_BROWSER_BROWSER_URL_HANDLER_H_