docshell/shistory/ChildSHistory.h

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 /**
   8  * ChildSHistory represents a view of session history from a child process. It
   9  * exposes getters for some cached history state, and mutators which are
  10  * implemented by communicating with the actual history storage.
  11  *
  12  * NOTE: Currently session history is in transition, meaning that we're still
  13  * using the legacy nsSHistory class internally. The API exposed from this class
  14  * should be only the API which we expect to expose when this transition is
  15  * complete, and special cases will need to call through the LegacySHistory()
  16  * getters.
  17  */
  18
  19 #ifndef mozilla_dom_ChildSHistory_h
  20 #define mozilla_dom_ChildSHistory_h
  21
  22 #include "nsCOMPtr.h"
  23 #include "mozilla/dom/BindingDeclarations.h"
  24 #include "nsWrapperCache.h"
  25 #include "nsThreadUtils.h"
  26 #include "mozilla/ErrorResult.h"
  27 #include "mozilla/LinkedList.h"
  28 #include "nsID.h"
  29
  30 class nsISHEntry;
  31 class nsISHistory;
  32
  33 namespace mozilla::dom {
  34
  35 class BrowsingContext;
  36
  37 class ChildSHistory : public nsISupports, public nsWrapperCache {
  38  public:
  39   NS_DECL_CYCLE_COLLECTING_ISUPPORTS
  40   NS_DECL_CYCLE_COLLECTION_WRAPPERCACHE_CLASS(ChildSHistory)
  41   nsISupports* GetParentObject() const;
  42   JSObject* WrapObject(JSContext* cx,
  43                        JS::Handle<JSObject*> aGivenProto) override;
  44
  45   explicit ChildSHistory(BrowsingContext* aBrowsingContext);
  46
  47   void SetBrowsingContext(BrowsingContext* aBrowsingContext);
  48
  49   // Create or destroy the session history implementation in the child process.
  50   // This can be removed once session history is stored exclusively in the
  51   // parent process.
  52   void SetIsInProcess(bool aIsInProcess);
  53   bool IsInProcess() { return !!mHistory; }
  54
  55   int32_t Count();
  56   int32_t Index();
  57
  58   /**
  59    * Reload the current entry in the session history.
  60    */
  61   void Reload(uint32_t aReloadFlags, ErrorResult& aRv);
  62
  63   /**
  64    * The CanGo and Go methods are called with an offset from the current index.
  65    * Positive numbers go forward in history, while negative numbers go
  66    * backwards.
  67    */
  68   bool CanGo(int32_t aOffset);
  69   void Go(int32_t aOffset, bool aRequireUserInteraction, bool aUserActivation,
  70           ErrorResult& aRv);
  71   void AsyncGo(int32_t aOffset, bool aRequireUserInteraction,
  72                bool aUserActivation, CallerType aCallerType, ErrorResult& aRv);
  73
  74   // aIndex is the new index, and aOffset is the offset between new and current.
  75   void GotoIndex(int32_t aIndex, int32_t aOffset, bool aRequireUserInteraction,
  76                  bool aUserActivation, ErrorResult& aRv);
  77
  78   void RemovePendingHistoryNavigations();
  79
  80   /**
  81    * Evicts all content viewers within the current process.
  82    */
  83   void EvictLocalDocumentViewers();
  84
  85   // GetLegacySHistory and LegacySHistory have been deprecated. Don't
  86   // use these, but instead handle the interaction with nsISHistory in
  87   // the parent process.
  88   nsISHistory* GetLegacySHistory(ErrorResult& aError);
  89   nsISHistory* LegacySHistory();
  90
  91   void SetIndexAndLength(uint32_t aIndex, uint32_t aLength,
  92                          const nsID& aChangeId);
  93   nsID AddPendingHistoryChange();
  94   nsID AddPendingHistoryChange(int32_t aIndexDelta, int32_t aLengthDelta);
  95
  96  private:
  97   virtual ~ChildSHistory();
  98
  99   class PendingAsyncHistoryNavigation
 100       : public Runnable,
 101         public mozilla::LinkedListElement<PendingAsyncHistoryNavigation> {
 102    public:
 103     PendingAsyncHistoryNavigation(ChildSHistory* aHistory, int32_t aOffset,
 104                                   bool aRequireUserInteraction,
 105                                   bool aUserActivation)
 106         : Runnable("PendingAsyncHistoryNavigation"),
 107           mHistory(aHistory),
 108           mRequireUserInteraction(aRequireUserInteraction),
 109           mUserActivation(aUserActivation),
 110           mOffset(aOffset) {}
 111
 112     NS_IMETHOD Run() override {
 113       if (isInList()) {
 114         remove();
 115         mHistory->Go(mOffset, mRequireUserInteraction, mUserActivation,
 116                      IgnoreErrors());
 117       }
 118       return NS_OK;
 119     }
 120
 121    private:
 122     RefPtr<ChildSHistory> mHistory;
 123     bool mRequireUserInteraction;
 124     bool mUserActivation;
 125     int32_t mOffset;
 126   };
 127
 128   RefPtr<BrowsingContext> mBrowsingContext;
 129   nsCOMPtr<nsISHistory> mHistory;
 130   // Can be removed once history-in-parent is the only way
 131   mozilla::LinkedList<PendingAsyncHistoryNavigation> mPendingNavigations;
 132   int32_t mIndex = -1;
 133   int32_t mLength = 0;
 134
 135   struct PendingSHistoryChange {
 136     nsID mChangeID;
 137     int32_t mIndexDelta;
 138     int32_t mLengthDelta;
 139   };
 140   AutoTArray<PendingSHistoryChange, 2> mPendingSHistoryChanges;
 141
 142   // Needs to start 1 above default epoch in parent
 143   uint64_t mHistoryEpoch = 1;
 144   bool mPendingEpoch = false;
 145 };
 146
 147 }  // namespace mozilla::dom
 148
 149 #endif /* mozilla_dom_ChildSHistory_h */