1 files changed, 39 insertions, 0 deletions
diff --git a/docshell/base/nsDocShellEnumerator.h b/docshell/base/nsDocShellEnumerator.h
new file mode 100644
index 0000000000..668ddee7e9
--- /dev/null
+++ b/docshell/base/nsDocShellEnumerator.h
@@ -0,0 +1,39 @@
+/* -*- 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 nsDocShellEnumerator_h___
+#define nsDocShellEnumerator_h___
+
+#include "nsTArray.h"
+
+class nsDocShell;
+class nsIDocShell;
+
+class MOZ_STACK_CLASS nsDocShellEnumerator {
+ public:
+  enum class EnumerationDirection : uint8_t { Forwards, Backwards };
+
+  nsDocShellEnumerator(EnumerationDirection aDirection, int32_t aDocShellType,
+                       nsDocShell& aRootItem);
+
+ public:
+  nsresult BuildDocShellArray(nsTArray<RefPtr<nsIDocShell>>& aItemArray);
+
+ private:
+  nsresult BuildArrayRecursiveForwards(
+      nsDocShell* aItem, nsTArray<RefPtr<nsIDocShell>>& aItemArray);
+  nsresult BuildArrayRecursiveBackwards(
+      nsDocShell* aItem, nsTArray<RefPtr<nsIDocShell>>& aItemArray);
+
+ private:
+  const RefPtr<nsDocShell> mRootItem;
+
+  const int32_t mDocShellType;  // only want shells of this type
+
+  const EnumerationDirection mDirection;
+};
+
+#endif  // nsDocShellEnumerator_h___