chrome/browser/prerender/prerender_tracker.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_PRERENDER_PRERENDER_TRACKER_H_
   6 #define CHROME_BROWSER_PRERENDER_PRERENDER_TRACKER_H_
   7
   8 #include <map>
   9 #include <set>
  10 #include <utility>
  11 #include <vector>
  12
  13 #include "base/gtest_prod_util.h"
  14 #include "base/memory/weak_ptr.h"
  15 #include "base/synchronization/lock.h"
  16 #include "base/threading/non_thread_safe.h"
  17 #include "chrome/browser/prerender/prerender_contents.h"
  18 #include "chrome/browser/prerender/prerender_final_status.h"
  19 #include "url/gurl.h"
  20
  21 namespace prerender {
  22
  23 class PrerenderManager;
  24 class PrerenderPendingSwapThrottle;
  25 class PrerenderResourceThrottle;
  26 struct RenderViewInfo;
  27
  28 // PrerenderTracker is responsible for keeping track of all prerendering
  29 // RenderViews.
  30 class PrerenderTracker : public base::NonThreadSafe,
  31                          public PrerenderContents::Observer {
  32  public:
  33   typedef std::pair<int, int> ChildRouteIdPair;
  34
  35   PrerenderTracker();
  36   virtual ~PrerenderTracker();
  37
  38   // Returns whether or not a RenderView is prerendering.  Can only be called on
  39   // the IO thread.  Does not acquire a lock, so may claim a RenderView that has
  40   // been displayed or destroyed is still prerendering.
  41   bool IsPrerenderingOnIOThread(int child_id, int route_id) const;
  42
  43   // Returns whether or not a RenderFrame and URL are regarding a pending
  44   // prerender swap. Can only be called on the IO thread. Does not acquire a
  45   // lock.
  46   bool IsPendingSwapRequestOnIOThread(int render_process_id,
  47                                       int render_frame_id,
  48                                       const GURL& url) const;
  49
  50   // Called when a PrerenderResourceThrottle defers a request. Cancel
  51   // or Resume will be called on |throttle| when the prerender is
  52   // canceled or used, respectively.
  53   void AddResourceThrottleOnIOThread(
  54       int child_id, int route_id,
  55       const base::WeakPtr<PrerenderResourceThrottle>& throttle);
  56
  57   // Called when a PrerenderResourceThrottle defers a request. Cancel
  58   // or Resume will be called on |throttle| when the prerender is
  59   // canceled or used, respectively.
  60   void AddPendingSwapThrottleOnIOThread(
  61       int render_process_id, int render_frame_id, const GURL& url,
  62       const base::WeakPtr<PrerenderPendingSwapThrottle>& throttle);
  63
  64   // Called to add throttles for a pending prerender swap.
  65   void AddPrerenderPendingSwap(
  66       const ChildRouteIdPair& render_frame_route_id_pair,
  67       const GURL& url);
  68
  69   // Called to remove the throttles for a pending prerender swap.
  70   void RemovePrerenderPendingSwap(
  71       const ChildRouteIdPair& render_frame_route_id_pair,
  72       bool swap_successful);
  73
  74  private:
  75   friend class PrerenderContents;
  76
  77   // Map of child/route id pairs to final statuses.
  78   typedef std::map<ChildRouteIdPair, RenderViewInfo> FinalStatusMap;
  79   // List of throttled requests.
  80   typedef std::vector<base::WeakPtr<PrerenderResourceThrottle> >
  81       ResourceThrottleList;
  82   // Set of throttled requests.
  83   typedef std::map<ChildRouteIdPair, ResourceThrottleList> ResourceThrottleMap;
  84   struct PendingSwapThrottleData {
  85     explicit PendingSwapThrottleData(const GURL& swap_url);
  86     ~PendingSwapThrottleData();
  87     GURL url;
  88     base::WeakPtr<PrerenderPendingSwapThrottle> throttle;
  89   };
  90   // Set of throttles for pending swaps. The key is the routing ID pair
  91   // of a RenderFrame.
  92   typedef std::map<ChildRouteIdPair, PendingSwapThrottleData>
  93       PendingSwapThrottleMap;
  94
  95   // From PrerenderContents::Observer:
  96   virtual void OnPrerenderStart(PrerenderContents* prerender_contents) OVERRIDE;
  97   virtual void OnPrerenderStop(PrerenderContents* prerender_contents) OVERRIDE;
  98
  99   // Add/remove the specified pair to |possibly_prerendering_io_thread_set_| on
 100   // the IO Thread.
 101   void AddPrerenderOnIOThread(const ChildRouteIdPair& child_route_id_pair);
 102   void RemovePrerenderOnIOThread(const ChildRouteIdPair& child_route_id_pair,
 103                                  FinalStatus final_status);
 104
 105   // Add/remove prerenders pending swap on the IO Thread.
 106   void AddPrerenderPendingSwapOnIOThread(
 107       const ChildRouteIdPair& render_frame_route_id_pair, const GURL& url);
 108   void RemovePrerenderPendingSwapOnIOThread(
 109       const ChildRouteIdPair& render_frame_route_id_pair,
 110       bool swap_successful);
 111
 112   static PrerenderTracker* GetDefault();
 113
 114   // Resources that are throttled, pending a prerender use.  The keys are a
 115   // superset of child/route id pairs that are prerendering.  Can only access on
 116   // the IO thread.  May contain entries that have since been displayed.  Used
 117   // to prevent locking when not needed.
 118   ResourceThrottleMap resource_throttle_io_thread_map_;
 119
 120   // Map of pending prerender swaps and their associated throttles,
 121   // maintained on the IO thread.
 122   PendingSwapThrottleMap pending_swap_throttle_map_;
 123
 124   DISALLOW_COPY_AND_ASSIGN(PrerenderTracker);
 125 };
 126
 127 }  // namespace prerender
 128
 129 #endif  // CHROME_BROWSER_PRERENDER_PRERENDER_TRACKER_H_