michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: #include "nsSHEntryShared.h"
michael@0: 
michael@0: #include "nsIDOMDocument.h"
michael@0: #include "nsISHistory.h"
michael@0: #include "nsISHistoryInternal.h"
michael@0: #include "nsIDocument.h"
michael@0: #include "nsIWebNavigation.h"
michael@0: #include "nsIContentViewer.h"
michael@0: #include "nsIDocShell.h"
michael@0: #include "nsIDocShellTreeItem.h"
michael@0: #include "nsDocShellEditorData.h"
michael@0: #include "nsThreadUtils.h"
michael@0: #include "nsILayoutHistoryState.h"
michael@0: #include "mozilla/Attributes.h"
michael@0: #include "nsISupportsArray.h"
michael@0: 
michael@0: namespace dom = mozilla::dom;
michael@0: 
michael@0: namespace {
michael@0: 
michael@0: uint64_t gSHEntrySharedID = 0;
michael@0: 
michael@0: } // anonymous namespace
michael@0: 
michael@0: // Hardcode this to time out unused content viewers after 30 minutes
michael@0: // XXX jlebar shouldn't this be a pref?
michael@0: #define CONTENT_VIEWER_TIMEOUT_SECONDS (30*60)
michael@0: 
michael@0: typedef nsExpirationTracker<nsSHEntryShared, 3> HistoryTrackerBase;
michael@0: class HistoryTracker MOZ_FINAL : public HistoryTrackerBase {
michael@0: public:
michael@0:   // Expire cached contentviewers after 20-30 minutes in the cache.
michael@0:   HistoryTracker() 
michael@0:     : HistoryTrackerBase(1000 * CONTENT_VIEWER_TIMEOUT_SECONDS / 2)
michael@0:   {
michael@0:   }
michael@0:   
michael@0: protected:
michael@0:   virtual void NotifyExpired(nsSHEntryShared *aObj) {
michael@0:     RemoveObject(aObj);
michael@0:     aObj->Expire();
michael@0:   }
michael@0: };
michael@0: 
michael@0: static HistoryTracker *gHistoryTracker = nullptr;
michael@0: 
michael@0: void
michael@0: nsSHEntryShared::Startup()
michael@0: {
michael@0:   gHistoryTracker = new HistoryTracker();
michael@0: }
michael@0: 
michael@0: void
michael@0: nsSHEntryShared::Shutdown()
michael@0: {
michael@0:   delete gHistoryTracker;
michael@0:   gHistoryTracker = nullptr;
michael@0: }
michael@0: 
michael@0: nsSHEntryShared::nsSHEntryShared()
michael@0:   : mDocShellID(0)
michael@0:   , mIsFrameNavigation(false)
michael@0:   , mSaveLayoutState(true)
michael@0:   , mSticky(true)
michael@0:   , mDynamicallyCreated(false)
michael@0:   , mLastTouched(0)
michael@0:   , mID(gSHEntrySharedID++)
michael@0:   , mExpired(false)
michael@0:   , mViewerBounds(0, 0, 0, 0)
michael@0: {
michael@0: }
michael@0: 
michael@0: nsSHEntryShared::~nsSHEntryShared()
michael@0: {
michael@0:   RemoveFromExpirationTracker();
michael@0: 
michael@0: #ifdef DEBUG
michael@0:   // Check that we're not still on track to expire.  We shouldn't be, because
michael@0:   // we just removed ourselves!
michael@0:   nsExpirationTracker<nsSHEntryShared, 3>::Iterator
michael@0:     iterator(gHistoryTracker);
michael@0: 
michael@0:   nsSHEntryShared *elem;
michael@0:   while ((elem = iterator.Next()) != nullptr) {
michael@0:     NS_ASSERTION(elem != this, "Found dead entry still in the tracker!");
michael@0:   }
michael@0: #endif
michael@0: 
michael@0:   if (mContentViewer) {
michael@0:     RemoveFromBFCacheSync();
michael@0:   }
michael@0: }
michael@0: 
michael@0: NS_IMPL_ISUPPORTS(nsSHEntryShared, nsIBFCacheEntry, nsIMutationObserver)
michael@0: 
michael@0: already_AddRefed<nsSHEntryShared>
michael@0: nsSHEntryShared::Duplicate(nsSHEntryShared *aEntry)
michael@0: {
michael@0:   nsRefPtr<nsSHEntryShared> newEntry = new nsSHEntryShared();
michael@0: 
michael@0:   newEntry->mDocShellID = aEntry->mDocShellID;
michael@0:   newEntry->mChildShells.AppendObjects(aEntry->mChildShells);
michael@0:   newEntry->mOwner = aEntry->mOwner;
michael@0:   newEntry->mContentType.Assign(aEntry->mContentType);
michael@0:   newEntry->mIsFrameNavigation = aEntry->mIsFrameNavigation;
michael@0:   newEntry->mSaveLayoutState = aEntry->mSaveLayoutState;
michael@0:   newEntry->mSticky = aEntry->mSticky;
michael@0:   newEntry->mDynamicallyCreated = aEntry->mDynamicallyCreated;
michael@0:   newEntry->mCacheKey = aEntry->mCacheKey;
michael@0:   newEntry->mLastTouched = aEntry->mLastTouched;
michael@0: 
michael@0:   return newEntry.forget();
michael@0: }
michael@0: 
michael@0: void nsSHEntryShared::RemoveFromExpirationTracker()
michael@0: {
michael@0:   if (GetExpirationState()->IsTracked()) {
michael@0:     gHistoryTracker->RemoveObject(this);
michael@0:   }
michael@0: }
michael@0: 
michael@0: nsresult
michael@0: nsSHEntryShared::SyncPresentationState()
michael@0: {
michael@0:   if (mContentViewer && mWindowState) {
michael@0:     // If we have a content viewer and a window state, we should be ok.
michael@0:     return NS_OK;
michael@0:   }
michael@0: 
michael@0:   DropPresentationState();
michael@0: 
michael@0:   return NS_OK;
michael@0: }
michael@0: 
michael@0: void
michael@0: nsSHEntryShared::DropPresentationState()
michael@0: {
michael@0:   nsRefPtr<nsSHEntryShared> kungFuDeathGrip = this;
michael@0: 
michael@0:   if (mDocument) {
michael@0:     mDocument->SetBFCacheEntry(nullptr);
michael@0:     mDocument->RemoveMutationObserver(this);
michael@0:     mDocument = nullptr;
michael@0:   }
michael@0:   if (mContentViewer) {
michael@0:     mContentViewer->ClearHistoryEntry();
michael@0:   }
michael@0: 
michael@0:   RemoveFromExpirationTracker();
michael@0:   mContentViewer = nullptr;
michael@0:   mSticky = true;
michael@0:   mWindowState = nullptr;
michael@0:   mViewerBounds.SetRect(0, 0, 0, 0);
michael@0:   mChildShells.Clear();
michael@0:   mRefreshURIList = nullptr;
michael@0:   mEditorData = nullptr;
michael@0: }
michael@0: 
michael@0: void
michael@0: nsSHEntryShared::Expire()
michael@0: {
michael@0:   // This entry has timed out. If we still have a content viewer, we need to
michael@0:   // evict it.
michael@0:   if (!mContentViewer) {
michael@0:     return;
michael@0:   }
michael@0:   nsCOMPtr<nsIDocShell> container;
michael@0:   mContentViewer->GetContainer(getter_AddRefs(container));
michael@0:   nsCOMPtr<nsIDocShellTreeItem> treeItem = do_QueryInterface(container);
michael@0:   if (!treeItem) {
michael@0:     return;
michael@0:   }
michael@0:   // We need to find the root DocShell since only that object has an
michael@0:   // SHistory and we need the SHistory to evict content viewers
michael@0:   nsCOMPtr<nsIDocShellTreeItem> root;
michael@0:   treeItem->GetSameTypeRootTreeItem(getter_AddRefs(root));
michael@0:   nsCOMPtr<nsIWebNavigation> webNav = do_QueryInterface(root);
michael@0:   nsCOMPtr<nsISHistory> history;
michael@0:   webNav->GetSessionHistory(getter_AddRefs(history));
michael@0:   nsCOMPtr<nsISHistoryInternal> historyInt = do_QueryInterface(history);
michael@0:   if (!historyInt) {
michael@0:     return;
michael@0:   }
michael@0:   historyInt->EvictExpiredContentViewerForEntry(this);
michael@0: }
michael@0: 
michael@0: nsresult
michael@0: nsSHEntryShared::SetContentViewer(nsIContentViewer *aViewer)
michael@0: {
michael@0:   NS_PRECONDITION(!aViewer || !mContentViewer,
michael@0:                   "SHEntryShared already contains viewer");
michael@0: 
michael@0:   if (mContentViewer || !aViewer) {
michael@0:     DropPresentationState();
michael@0:   }
michael@0: 
michael@0:   mContentViewer = aViewer;
michael@0: 
michael@0:   if (mContentViewer) {
michael@0:     gHistoryTracker->AddObject(this);
michael@0: 
michael@0:     nsCOMPtr<nsIDOMDocument> domDoc;
michael@0:     mContentViewer->GetDOMDocument(getter_AddRefs(domDoc));
michael@0:     // Store observed document in strong pointer in case it is removed from
michael@0:     // the contentviewer
michael@0:     mDocument = do_QueryInterface(domDoc);
michael@0:     if (mDocument) {
michael@0:       mDocument->SetBFCacheEntry(this);
michael@0:       mDocument->AddMutationObserver(this);
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   return NS_OK;
michael@0: }
michael@0: 
michael@0: nsresult
michael@0: nsSHEntryShared::RemoveFromBFCacheSync()
michael@0: {
michael@0:   NS_ASSERTION(mContentViewer && mDocument,
michael@0:                "we're not in the bfcache!");
michael@0: 
michael@0:   nsCOMPtr<nsIContentViewer> viewer = mContentViewer;
michael@0:   DropPresentationState();
michael@0: 
michael@0:   // Warning! The call to DropPresentationState could have dropped the last
michael@0:   // reference to this object, so don't access members beyond here.
michael@0: 
michael@0:   if (viewer) {
michael@0:     viewer->Destroy();
michael@0:   }
michael@0: 
michael@0:   return NS_OK;
michael@0: }
michael@0: 
michael@0: class DestroyViewerEvent : public nsRunnable
michael@0: {
michael@0: public:
michael@0:   DestroyViewerEvent(nsIContentViewer* aViewer, nsIDocument* aDocument)
michael@0:     : mViewer(aViewer),
michael@0:       mDocument(aDocument)
michael@0:   {}
michael@0: 
michael@0:   NS_IMETHOD Run()
michael@0:   {
michael@0:     if (mViewer) {
michael@0:       mViewer->Destroy();
michael@0:     }
michael@0:     return NS_OK;
michael@0:   }
michael@0: 
michael@0:   nsCOMPtr<nsIContentViewer> mViewer;
michael@0:   nsCOMPtr<nsIDocument> mDocument;
michael@0: };
michael@0: 
michael@0: nsresult
michael@0: nsSHEntryShared::RemoveFromBFCacheAsync()
michael@0: {
michael@0:   NS_ASSERTION(mContentViewer && mDocument,
michael@0:                "we're not in the bfcache!");
michael@0: 
michael@0:   // Release the reference to the contentviewer asynchronously so that the
michael@0:   // document doesn't get nuked mid-mutation.
michael@0: 
michael@0:   nsCOMPtr<nsIRunnable> evt =
michael@0:     new DestroyViewerEvent(mContentViewer, mDocument);
michael@0:   nsresult rv = NS_DispatchToCurrentThread(evt);
michael@0:   if (NS_FAILED(rv)) {
michael@0:     NS_WARNING("failed to dispatch DestroyViewerEvent");
michael@0:   } else {
michael@0:     // Drop presentation. Only do this if we succeeded in posting the event
michael@0:     // since otherwise the document could be torn down mid-mutation, causing
michael@0:     // crashes.
michael@0:     DropPresentationState();
michael@0:   }
michael@0: 
michael@0:   // Careful! The call to DropPresentationState could have dropped the last
michael@0:   // reference to this nsSHEntryShared, so don't access members beyond here.
michael@0: 
michael@0:   return NS_OK;
michael@0: }
michael@0: 
michael@0: nsresult
michael@0: nsSHEntryShared::GetID(uint64_t *aID)
michael@0: {
michael@0:   *aID = mID;
michael@0:   return NS_OK;
michael@0: }
michael@0: 
michael@0: //*****************************************************************************
michael@0: //    nsSHEntryShared: nsIMutationObserver
michael@0: //*****************************************************************************
michael@0: 
michael@0: void
michael@0: nsSHEntryShared::NodeWillBeDestroyed(const nsINode* aNode)
michael@0: {
michael@0:   NS_NOTREACHED("Document destroyed while we're holding a strong ref to it");
michael@0: }
michael@0: 
michael@0: void
michael@0: nsSHEntryShared::CharacterDataWillChange(nsIDocument* aDocument,
michael@0:                                          nsIContent* aContent,
michael@0:                                          CharacterDataChangeInfo* aInfo)
michael@0: {
michael@0: }
michael@0: 
michael@0: void
michael@0: nsSHEntryShared::CharacterDataChanged(nsIDocument* aDocument,
michael@0:                                       nsIContent* aContent,
michael@0:                                       CharacterDataChangeInfo* aInfo)
michael@0: {
michael@0:   RemoveFromBFCacheAsync();
michael@0: }
michael@0: 
michael@0: void
michael@0: nsSHEntryShared::AttributeWillChange(nsIDocument* aDocument,
michael@0:                                      dom::Element* aContent,
michael@0:                                      int32_t aNameSpaceID,
michael@0:                                      nsIAtom* aAttribute,
michael@0:                                      int32_t aModType)
michael@0: {
michael@0: }
michael@0: 
michael@0: void
michael@0: nsSHEntryShared::AttributeChanged(nsIDocument* aDocument,
michael@0:                                   dom::Element* aElement,
michael@0:                                   int32_t aNameSpaceID,
michael@0:                                   nsIAtom* aAttribute,
michael@0:                                   int32_t aModType)
michael@0: {
michael@0:   RemoveFromBFCacheAsync();
michael@0: }
michael@0: 
michael@0: void
michael@0: nsSHEntryShared::ContentAppended(nsIDocument* aDocument,
michael@0:                                  nsIContent* aContainer,
michael@0:                                  nsIContent* aFirstNewContent,
michael@0:                                  int32_t /* unused */)
michael@0: {
michael@0:   RemoveFromBFCacheAsync();
michael@0: }
michael@0: 
michael@0: void
michael@0: nsSHEntryShared::ContentInserted(nsIDocument* aDocument,
michael@0:                                  nsIContent* aContainer,
michael@0:                                  nsIContent* aChild,
michael@0:                                  int32_t /* unused */)
michael@0: {
michael@0:   RemoveFromBFCacheAsync();
michael@0: }
michael@0: 
michael@0: void
michael@0: nsSHEntryShared::ContentRemoved(nsIDocument* aDocument,
michael@0:                                 nsIContent* aContainer,
michael@0:                                 nsIContent* aChild,
michael@0:                                 int32_t aIndexInContainer,
michael@0:                                 nsIContent* aPreviousSibling)
michael@0: {
michael@0:   RemoveFromBFCacheAsync();
michael@0: }
michael@0: 
michael@0: void
michael@0: nsSHEntryShared::ParentChainChanged(nsIContent *aContent)
michael@0: {
michael@0: }