Add m-esr52 at 52.6.0

1 files changed, 105 insertions, 0 deletions

diff --git a/dom/base/GroupedSHistory.h b/dom/base/GroupedSHistory.h
new file mode 100644
index 000000000..8c88a0aaf
--- /dev/null
+++ b/dom/base/GroupedSHistory.h
@@ -0,0 +1,105 @@
+/* -*- 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/. */
+
+#ifndef GroupedSHistory_h
+#define GroupedSHistory_h
+
+#include "nsIFrameLoader.h"
+#include "nsIGroupedSHistory.h"
+#include "nsIPartialSHistory.h"
+#include "nsTArray.h"
+#include "nsWeakReference.h"
+
+namespace mozilla {
+namespace dom {
+
+
+/**
+ * GroupedSHistory connects session histories across multiple frameloaders.
+ * Each frameloader has a PartialSHistory, and GroupedSHistory has an array
+ * refering to all participating PartialSHistory(s).
+ *
+ * The following figure illustrates the idea. In this case, the GroupedSHistory
+ * is composed of 3 frameloaders, and the active one is frameloader 1.
+ * GroupedSHistory is always attached to the active frameloader.
+ *
+ *            +----------------------------------------------------+
+ *            |                                                    |
+ *            |                                                    v
+ *  +------------------+      +-------------------+       +-----------------+
+ *  |  FrameLoader 1   |      | PartialSHistory 1 |       | GroupedSHistory |
+ *  |     (active)     |----->|     (active)      |<--+---|                 |
+ *  +------------------+      +-------------------+   |   +-----------------+
+ *                                                    |
+ *  +------------------+      +-------------------+   |
+ *  |  FrameLoader 2   |      | PartialSHistory 2 |   |
+ *  |    (inactive)    |----->|    (inactive)     |<--+
+ *  +------------------+      +-------------------+   |
+ *                                                    |
+ *  +------------------+      +-------------------+   |
+ *  |  FrameLoader 3   |      | PartialSHistory 3 |   |
+ *  |    (inactive)    |----->|    (inactive)     |<--+
+ *  +------------------+      +-------------------+
+ *
+ * If a history navigation leads to frameloader 3, it becomes the active one,
+ * and GroupedSHistory is re-attached to frameloader 3.
+ *
+ *  +------------------+      +-------------------+
+ *  |  FrameLoader 1   |      | PartialSHistory 1 |
+ *  |    (inactive)    |----->|    (inactive)     |<--+
+ *  +------------------+      +-------------------+   |
+ *                                                    |
+ *  +------------------+      +-------------------+   |
+ *  |  FrameLoader 2   |      | PartialSHistory 2 |   |
+ *  |    (inactive)    |----->|    (inactive)     |<--+
+ *  +------------------+      +-------------------+   |
+ *                                                    |
+ *  +------------------+      +-------------------+   |   +-----------------+
+ *  |  FrameLoader 3   |      | PartialSHistory 3 |   |   | GroupedSHistory |
+ *  |     (active)     |----->|     (active)      |<--+---|                 |
+ *  +------------------+      +-------------------+       +-----------------+
+ *            |                                                    ^
+ *            |                                                    |
+ *            +----------------------------------------------------+
+ */
+class GroupedSHistory final : public nsIGroupedSHistory
+{
+public:
+  NS_DECL_CYCLE_COLLECTING_ISUPPORTS
+  NS_DECL_CYCLE_COLLECTION_CLASS(GroupedSHistory)
+  NS_DECL_NSIGROUPEDSHISTORY
+  GroupedSHistory();
+
+  /**
+   * Get the value of preference "browser.groupedhistory.enabled" to determine
+   * if grouped session history should be enabled.
+   */
+  static bool GroupedHistoryEnabled();
+
+private:
+  ~GroupedSHistory() {}
+
+  /**
+   * Remove all partial histories and close tabs after the given index (of
+   * mPartialHistories, not the index of session history entries).
+   */
+  void PurgePartialHistories(uint32_t aLastPartialIndexToKeep);
+
+  // The total number of entries in all partial histories.
+  uint32_t mCount;
+
+  // The index of currently active partial history in mPartialHistories.
+  // Use int32_t as we have invalid index and nsCOMArray also uses int32_t.
+  int32_t mIndexOfActivePartialHistory;
+
+  // All participating nsIPartialSHistory objects.
+  nsCOMArray<nsIPartialSHistory> mPartialHistories;
+};
+
+} // namespace dom
+} // namespace mozilla
+
+#endif /* GroupedSHistory_h */