content/renderer/history_controller.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 /*
   6  * Copyright (C) 2006, 2007, 2008, 2009 Apple Inc. All rights reserved.
   7  * Copyright (C) 2008, 2009 Torch Mobile Inc. All rights reserved.
   8  *     (http://www.torchmobile.com/)
   9  *
  10  * Redistribution and use in source and binary forms, with or without
  11  * modification, are permitted provided that the following conditions
  12  * are met:
  13  *
  14  * 1.  Redistributions of source code must retain the above copyright
  15  *     notice, this list of conditions and the following disclaimer.
  16  * 2.  Redistributions in binary form must reproduce the above copyright
  17  *     notice, this list of conditions and the following disclaimer in the
  18  *     documentation and/or other materials provided with the distribution.
  19  * 3.  Neither the name of Apple Computer, Inc. ("Apple") nor the names of
  20  *     its contributors may be used to endorse or promote products derived
  21  *     from this software without specific prior written permission.
  22  *
  23  * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
  24  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  25  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  26  * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
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  30  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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  34
  35 #ifndef CONTENT_RENDERER_HISTORY_CONTROLLER_H_
  36 #define CONTENT_RENDERER_HISTORY_CONTROLLER_H_
  37
  38 #include "base/containers/hash_tables.h"
  39 #include "base/memory/scoped_ptr.h"
  40 #include "base/memory/scoped_vector.h"
  41 #include "content/common/content_export.h"
  42 #include "content/renderer/history_entry.h"
  43 #include "third_party/WebKit/public/platform/WebURLRequest.h"
  44 #include "third_party/WebKit/public/web/WebHistoryCommitType.h"
  45 #include "third_party/WebKit/public/web/WebHistoryItem.h"
  46
  47 namespace blink {
  48 class WebFrame;
  49 }
  50
  51 namespace content {
  52 class RenderFrameImpl;
  53 class RenderViewImpl;
  54
  55 // A guide to history state in the renderer:
  56 //
  57 // HistoryController: Owned by RenderView, is the entry point for interacting
  58 //     with history. Handles most of the operations to modify history state,
  59 //     navigate to an existing back/forward entry, etc.
  60 //
  61 // HistoryEntry: Represents a single entry in the back/forward list,
  62 //     encapsulating all frames in the page it represents. It provides access
  63 //     to each frame's state via lookups by frame id or frame name.
  64 // HistoryNode: Represents a single frame in a HistoryEntry. Owned by a
  65 //     HistoryEntry. HistoryNodes form a tree that mirrors the frame tree in
  66 //     the corresponding page.
  67 // HistoryNodes represent the structure of the page, but don't hold any
  68 // per-frame state except a list of child frames.
  69 // WebHistoryItem (lives in blink): The state for a given frame. Can persist
  70 //     across navigations. WebHistoryItem is reference counted, and each
  71 //     HistoryNode holds a reference to its single corresponding
  72 //     WebHistoryItem. Can be referenced by multiple HistoryNodes and can
  73 //     therefore exist in multiple HistoryEntry instances.
  74 //
  75 // Suppose we have the following page, foo.com, which embeds foo.com/a in an
  76 // iframe:
  77 //
  78 // HistoryEntry 0:
  79 //     HistoryNode 0_0 (WebHistoryItem A (url: foo.com))
  80 //         HistoryNode 0_1: (WebHistoryItem B (url: foo.com/a))
  81 //
  82 // Now we navigate the top frame to bar.com, which embeds bar.com/b and
  83 // bar.com/c in iframes, and bar.com/b in turn embeds bar.com/d. We will
  84 // create a new HistoryEntry with a tree containing 4 new HistoryNodes. The
  85 // state will be:
  86 //
  87 // HistoryEntry 1:
  88 //     HistoryNode 1_0 (WebHistoryItem C (url: bar.com))
  89 //         HistoryNode 1_1: (WebHistoryItem D (url: bar.com/b))
  90 //             HistoryNode 1_3: (WebHistoryItem F (url: bar.com/d))
  91 //         HistoryNode 1_2: (WebHistoryItem E (url: bar.com/c))
  92 //
  93 //
  94 // Finally, we navigate the first subframe from bar.com/b to bar.com/e, which
  95 // embeds bar.com/f. We will create a new HistoryEntry and new HistoryNode for
  96 // each frame. Any frame that navigates (bar.com/e and its child, bar.com/f)
  97 // will receive a new WebHistoryItem. However, 2 frames were not navigated
  98 // (bar.com and bar.com/c), so those two frames will reuse the existing
  99 // WebHistoryItem:
 100 //
 101 // HistoryEntry 2:
 102 //     HistoryNode 2_0 (WebHistoryItem C (url: bar.com))  *REUSED*
 103 //         HistoryNode 2_1: (WebHistoryItem G (url: bar.com/e))
 104 //            HistoryNode 2_3: (WebHistoryItem H (url: bar.com/f))
 105 //         HistoryNode 2_2: (WebHistoryItem E (url: bar.com/c)) *REUSED*
 106 //
 107 class CONTENT_EXPORT HistoryController {
 108  public:
 109   explicit HistoryController(RenderViewImpl* render_view);
 110   ~HistoryController();
 111
 112   void GoToEntry(scoped_ptr<HistoryEntry> entry,
 113                  blink::WebURLRequest::CachePolicy cache_policy);
 114
 115   void UpdateForCommit(RenderFrameImpl* frame,
 116                        const blink::WebHistoryItem& item,
 117                        blink::WebHistoryCommitType commit_type,
 118                        bool navigation_within_page);
 119
 120   HistoryEntry* GetCurrentEntry();
 121   HistoryEntry* GetPreviousEntry();
 122   blink::WebHistoryItem GetItemForNewChildFrame(RenderFrameImpl* frame) const;
 123   void RemoveChildrenForRedirect(RenderFrameImpl* frame);
 124
 125  private:
 126   typedef std::vector<std::pair<blink::WebFrame*, blink::WebHistoryItem> >
 127       HistoryFrameLoadVector;
 128   void RecursiveGoToEntry(blink::WebFrame* frame,
 129                           HistoryFrameLoadVector& sameDocumentLoads,
 130                           HistoryFrameLoadVector& differentDocumentLoads);
 131
 132   void UpdateForInitialLoadInChildFrame(RenderFrameImpl* frame,
 133                                         const blink::WebHistoryItem& item);
 134   void CreateNewBackForwardItem(RenderFrameImpl* frame,
 135                                 const blink::WebHistoryItem& item,
 136                                 bool clone_children_of_target);
 137
 138   RenderViewImpl* render_view_;
 139
 140   scoped_ptr<HistoryEntry> current_entry_;
 141   scoped_ptr<HistoryEntry> previous_entry_;
 142   scoped_ptr<HistoryEntry> provisional_entry_;
 143
 144   DISALLOW_COPY_AND_ASSIGN(HistoryController);
 145 };
 146
 147 }  // namespace content
 148
 149 #endif  // CONTENT_RENDERER_HISTORY_CONTROLLER_H_