From a4ec611b4f06371956bf8d1db50b0e36daf47ad4 Mon Sep 17 00:00:00 2001
From: Ben Kelly <ben@wanderview.com>
Date: Tue, 10 Feb 2015 23:55:43 -0500
Subject: [PATCH] Bug 1100398 P1 Add the nsICloneableInputStream interface.
 r=froydnj

---
 xpcom/io/moz.build                   |  1 +
 xpcom/io/nsICloneableInputStream.idl | 22 ++++++++++++++++++++++
 2 files changed, 23 insertions(+)
 create mode 100644 xpcom/io/nsICloneableInputStream.idl

diff --git a/xpcom/io/moz.build b/xpcom/io/moz.build
index 9c470c9fe76..b4dfc03b468 100644
--- a/xpcom/io/moz.build
+++ b/xpcom/io/moz.build
@@ -9,6 +9,7 @@ XPIDL_SOURCES += [
     'nsIAsyncOutputStream.idl',
     'nsIBinaryInputStream.idl',
     'nsIBinaryOutputStream.idl',
+    'nsICloneableInputStream.idl',
     'nsIConverterInputStream.idl',
     'nsIConverterOutputStream.idl',
     'nsIDirectoryEnumerator.idl',
diff --git a/xpcom/io/nsICloneableInputStream.idl b/xpcom/io/nsICloneableInputStream.idl
new file mode 100644
index 00000000000..4fd9a74f7ad
--- /dev/null
+++ b/xpcom/io/nsICloneableInputStream.idl
@@ -0,0 +1,22 @@
+/* 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 "nsIInputStream.idl"
+
+[scriptable, builtinclass, uuid(8149be1f-44d3-4f14-8b65-a57a5fbbeb97)]
+interface nsICloneableInputStream : nsISupports
+{
+  // Allow streams that implement the interface to determine if cloning
+  // possible at runtime.  For example, this allows wrappers to check if
+  // their base stream supports cloning.
+  [infallible] readonly attribute boolean cloneable;
+
+  // Produce a copy of the current stream in the most efficient way possible.
+  // In this case "copy" means that both the original and cloned streams
+  // should produce the same bytes for all future reads.  Bytes that have
+  // already been consumed from the original stream are not copied to the
+  // clone.  Operations on the two streams should be completely independent
+  // after the clone() occurs.
+  nsIInputStream clone();
+};