Add m-esr52 at 52.6.0

1 files changed, 385 insertions, 0 deletions

diff --git a/docshell/shistory/nsSHEntryShared.cpp b/docshell/shistory/nsSHEntryShared.cpp
new file mode 100644
index 000000000..645294408
--- /dev/null
+++ b/docshell/shistory/nsSHEntryShared.cpp
@@ -0,0 +1,385 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "nsSHEntryShared.h"
+
+#include "nsIDOMDocument.h"
+#include "nsISHistory.h"
+#include "nsISHistoryInternal.h"
+#include "nsIDocument.h"
+#include "nsIWebNavigation.h"
+#include "nsIContentViewer.h"
+#include "nsIDocShell.h"
+#include "nsIDocShellTreeItem.h"
+#include "nsDocShellEditorData.h"
+#include "nsThreadUtils.h"
+#include "nsILayoutHistoryState.h"
+#include "mozilla/Attributes.h"
+#include "mozilla/Preferences.h"
+#include "nsArray.h"
+
+namespace dom = mozilla::dom;
+
+namespace {
+
+uint64_t gSHEntrySharedID = 0;
+
+} // namespace
+
+#define CONTENT_VIEWER_TIMEOUT_SECONDS "browser.sessionhistory.contentViewerTimeout"
+// Default this to time out unused content viewers after 30 minutes
+#define CONTENT_VIEWER_TIMEOUT_SECONDS_DEFAULT (30 * 60)
+
+typedef nsExpirationTracker<nsSHEntryShared, 3> HistoryTrackerBase;
+class HistoryTracker final : public HistoryTrackerBase
+{
+public:
+  explicit HistoryTracker(uint32_t aTimeout)
+    : HistoryTrackerBase(1000 * aTimeout / 2, "HistoryTracker")
+  {
+  }
+
+protected:
+  virtual void NotifyExpired(nsSHEntryShared* aObj)
+  {
+    RemoveObject(aObj);
+    aObj->Expire();
+  }
+};
+
+static HistoryTracker* gHistoryTracker = nullptr;
+
+void
+nsSHEntryShared::EnsureHistoryTracker()
+{
+  if (!gHistoryTracker) {
+    // nsExpirationTracker doesn't allow one to change the timer period,
+    // so just set it once when the history tracker is used for the first time.
+    gHistoryTracker = new HistoryTracker(
+      mozilla::Preferences::GetUint(CONTENT_VIEWER_TIMEOUT_SECONDS,
+                                    CONTENT_VIEWER_TIMEOUT_SECONDS_DEFAULT));
+  }
+}
+
+void
+nsSHEntryShared::Shutdown()
+{
+  delete gHistoryTracker;
+  gHistoryTracker = nullptr;
+}
+
+nsSHEntryShared::nsSHEntryShared()
+  : mDocShellID(0)
+  , mIsFrameNavigation(false)
+  , mSaveLayoutState(true)
+  , mSticky(true)
+  , mDynamicallyCreated(false)
+  , mLastTouched(0)
+  , mID(gSHEntrySharedID++)
+  , mExpired(false)
+  , mViewerBounds(0, 0, 0, 0)
+{
+}
+
+nsSHEntryShared::~nsSHEntryShared()
+{
+  RemoveFromExpirationTracker();
+
+#ifdef DEBUG
+  if (gHistoryTracker) {
+    // Check that we're not still on track to expire.  We shouldn't be, because
+    // we just removed ourselves!
+    nsExpirationTracker<nsSHEntryShared, 3>::Iterator iterator(gHistoryTracker);
+
+    nsSHEntryShared* elem;
+    while ((elem = iterator.Next()) != nullptr) {
+      NS_ASSERTION(elem != this, "Found dead entry still in the tracker!");
+    }
+  }
+#endif
+
+  if (mContentViewer) {
+    RemoveFromBFCacheSync();
+  }
+}
+
+NS_IMPL_ISUPPORTS(nsSHEntryShared, nsIBFCacheEntry, nsIMutationObserver)
+
+already_AddRefed<nsSHEntryShared>
+nsSHEntryShared::Duplicate(nsSHEntryShared* aEntry)
+{
+  RefPtr<nsSHEntryShared> newEntry = new nsSHEntryShared();
+
+  newEntry->mDocShellID = aEntry->mDocShellID;
+  newEntry->mChildShells.AppendObjects(aEntry->mChildShells);
+  newEntry->mTriggeringPrincipal = aEntry->mTriggeringPrincipal;
+  newEntry->mPrincipalToInherit = aEntry->mPrincipalToInherit;
+  newEntry->mContentType.Assign(aEntry->mContentType);
+  newEntry->mIsFrameNavigation = aEntry->mIsFrameNavigation;
+  newEntry->mSaveLayoutState = aEntry->mSaveLayoutState;
+  newEntry->mSticky = aEntry->mSticky;
+  newEntry->mDynamicallyCreated = aEntry->mDynamicallyCreated;
+  newEntry->mCacheKey = aEntry->mCacheKey;
+  newEntry->mLastTouched = aEntry->mLastTouched;
+
+  return newEntry.forget();
+}
+
+void
+nsSHEntryShared::RemoveFromExpirationTracker()
+{
+  if (gHistoryTracker && GetExpirationState()->IsTracked()) {
+    gHistoryTracker->RemoveObject(this);
+  }
+}
+
+nsresult
+nsSHEntryShared::SyncPresentationState()
+{
+  if (mContentViewer && mWindowState) {
+    // If we have a content viewer and a window state, we should be ok.
+    return NS_OK;
+  }
+
+  DropPresentationState();
+
+  return NS_OK;
+}
+
+void
+nsSHEntryShared::DropPresentationState()
+{
+  RefPtr<nsSHEntryShared> kungFuDeathGrip = this;
+
+  if (mDocument) {
+    mDocument->SetBFCacheEntry(nullptr);
+    mDocument->RemoveMutationObserver(this);
+    mDocument = nullptr;
+  }
+  if (mContentViewer) {
+    mContentViewer->ClearHistoryEntry();
+  }
+
+  RemoveFromExpirationTracker();
+  mContentViewer = nullptr;
+  mSticky = true;
+  mWindowState = nullptr;
+  mViewerBounds.SetRect(0, 0, 0, 0);
+  mChildShells.Clear();
+  mRefreshURIList = nullptr;
+  mEditorData = nullptr;
+}
+
+void
+nsSHEntryShared::Expire()
+{
+  // This entry has timed out. If we still have a content viewer, we need to
+  // evict it.
+  if (!mContentViewer) {
+    return;
+  }
+  nsCOMPtr<nsIDocShell> container;
+  mContentViewer->GetContainer(getter_AddRefs(container));
+  nsCOMPtr<nsIDocShellTreeItem> treeItem = do_QueryInterface(container);
+  if (!treeItem) {
+    return;
+  }
+  // We need to find the root DocShell since only that object has an
+  // SHistory and we need the SHistory to evict content viewers
+  nsCOMPtr<nsIDocShellTreeItem> root;
+  treeItem->GetSameTypeRootTreeItem(getter_AddRefs(root));
+  nsCOMPtr<nsIWebNavigation> webNav = do_QueryInterface(root);
+  nsCOMPtr<nsISHistory> history;
+  webNav->GetSessionHistory(getter_AddRefs(history));
+  nsCOMPtr<nsISHistoryInternal> historyInt = do_QueryInterface(history);
+  if (!historyInt) {
+    return;
+  }
+  historyInt->EvictExpiredContentViewerForEntry(this);
+}
+
+nsresult
+nsSHEntryShared::SetContentViewer(nsIContentViewer* aViewer)
+{
+  NS_PRECONDITION(!aViewer || !mContentViewer,
+                  "SHEntryShared already contains viewer");
+
+  if (mContentViewer || !aViewer) {
+    DropPresentationState();
+  }
+
+  mContentViewer = aViewer;
+
+  if (mContentViewer) {
+    EnsureHistoryTracker();
+    gHistoryTracker->AddObject(this);
+
+    nsCOMPtr<nsIDOMDocument> domDoc;
+    mContentViewer->GetDOMDocument(getter_AddRefs(domDoc));
+    // Store observed document in strong pointer in case it is removed from
+    // the contentviewer
+    mDocument = do_QueryInterface(domDoc);
+    if (mDocument) {
+      mDocument->SetBFCacheEntry(this);
+      mDocument->AddMutationObserver(this);
+    }
+  }
+
+  return NS_OK;
+}
+
+nsresult
+nsSHEntryShared::RemoveFromBFCacheSync()
+{
+  NS_ASSERTION(mContentViewer && mDocument, "we're not in the bfcache!");
+
+  nsCOMPtr<nsIContentViewer> viewer = mContentViewer;
+  DropPresentationState();
+
+  // Warning! The call to DropPresentationState could have dropped the last
+  // reference to this object, so don't access members beyond here.
+
+  if (viewer) {
+    viewer->Destroy();
+  }
+
+  return NS_OK;
+}
+
+class DestroyViewerEvent : public mozilla::Runnable
+{
+public:
+  DestroyViewerEvent(nsIContentViewer* aViewer, nsIDocument* aDocument)
+    : mViewer(aViewer)
+    , mDocument(aDocument)
+  {
+  }
+
+  NS_IMETHOD Run() override
+  {
+    if (mViewer) {
+      mViewer->Destroy();
+    }
+    return NS_OK;
+  }
+
+  nsCOMPtr<nsIContentViewer> mViewer;
+  nsCOMPtr<nsIDocument> mDocument;
+};
+
+nsresult
+nsSHEntryShared::RemoveFromBFCacheAsync()
+{
+  NS_ASSERTION(mContentViewer && mDocument, "we're not in the bfcache!");
+
+  // Release the reference to the contentviewer asynchronously so that the
+  // document doesn't get nuked mid-mutation.
+
+  nsCOMPtr<nsIRunnable> evt = new DestroyViewerEvent(mContentViewer, mDocument);
+  nsresult rv = NS_DispatchToCurrentThread(evt);
+  if (NS_FAILED(rv)) {
+    NS_WARNING("failed to dispatch DestroyViewerEvent");
+  } else {
+    // Drop presentation. Only do this if we succeeded in posting the event
+    // since otherwise the document could be torn down mid-mutation, causing
+    // crashes.
+    DropPresentationState();
+  }
+
+  // Careful! The call to DropPresentationState could have dropped the last
+  // reference to this nsSHEntryShared, so don't access members beyond here.
+
+  return NS_OK;
+}
+
+nsresult
+nsSHEntryShared::GetID(uint64_t* aID)
+{
+  *aID = mID;
+  return NS_OK;
+}
+
+void
+nsSHEntryShared::NodeWillBeDestroyed(const nsINode* aNode)
+{
+  NS_NOTREACHED("Document destroyed while we're holding a strong ref to it");
+}
+
+void
+nsSHEntryShared::CharacterDataWillChange(nsIDocument* aDocument,
+                                         nsIContent* aContent,
+                                         CharacterDataChangeInfo* aInfo)
+{
+}
+
+void
+nsSHEntryShared::CharacterDataChanged(nsIDocument* aDocument,
+                                      nsIContent* aContent,
+                                      CharacterDataChangeInfo* aInfo)
+{
+  RemoveFromBFCacheAsync();
+}
+
+void
+nsSHEntryShared::AttributeWillChange(nsIDocument* aDocument,
+                                     dom::Element* aContent,
+                                     int32_t aNameSpaceID,
+                                     nsIAtom* aAttribute,
+                                     int32_t aModType,
+                                     const nsAttrValue* aNewValue)
+{
+}
+
+void
+nsSHEntryShared::NativeAnonymousChildListChange(nsIDocument* aDocument,
+                                                nsIContent* aContent,
+                                                bool aIsRemove)
+{
+}
+
+void
+nsSHEntryShared::AttributeChanged(nsIDocument* aDocument,
+                                  dom::Element* aElement,
+                                  int32_t aNameSpaceID,
+                                  nsIAtom* aAttribute,
+                                  int32_t aModType,
+                                  const nsAttrValue* aOldValue)
+{
+  RemoveFromBFCacheAsync();
+}
+
+void
+nsSHEntryShared::ContentAppended(nsIDocument* aDocument,
+                                 nsIContent* aContainer,
+                                 nsIContent* aFirstNewContent,
+                                 int32_t /* unused */)
+{
+  RemoveFromBFCacheAsync();
+}
+
+void
+nsSHEntryShared::ContentInserted(nsIDocument* aDocument,
+                                 nsIContent* aContainer,
+                                 nsIContent* aChild,
+                                 int32_t /* unused */)
+{
+  RemoveFromBFCacheAsync();
+}
+
+void
+nsSHEntryShared::ContentRemoved(nsIDocument* aDocument,
+                                nsIContent* aContainer,
+                                nsIContent* aChild,
+                                int32_t aIndexInContainer,
+                                nsIContent* aPreviousSibling)
+{
+  RemoveFromBFCacheAsync();
+}
+
+void
+nsSHEntryShared::ParentChainChanged(nsIContent* aContent)
+{
+}