import FIREFOX_52_6_0esr_RELEASE from mozilla-esr52 hg repo

netwerk/base/nsIResumableChannel.idl

@@ -0,0 +1,39 @@
+/* -*- Mode: IDL; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/* 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 "nsISupports.idl"
+ 
+interface nsIStreamListener;
+
+[scriptable, uuid(4ad136fa-83af-4a22-a76e-503642c0f4a8)]
+interface nsIResumableChannel : nsISupports {
+    /**
+     * Prepare this channel for resuming. The request will not start until
+     * asyncOpen or open is called. Calling resumeAt after open or asyncOpen
+     * has been called has undefined behaviour.
+     *
+     * @param startPos the starting offset, in bytes, to use to download
+     * @param entityID information about the file, to match before obtaining
+     *  the file. Pass an empty string to use anything.
+     *
+     * During OnStartRequest, this channel will have a status of
+     *  NS_ERROR_NOT_RESUMABLE if the file cannot be resumed, eg because the
+     *  server doesn't support this. This error may occur even if startPos
+     *  is 0, so that the front end can warn the user.
+     * Similarly, the status of this channel during OnStartRequest may be
+     *  NS_ERROR_ENTITY_CHANGED, which indicates that the entity has changed,
+     *  as indicated by a changed entityID.
+     * In both of these cases, no OnDataAvailable will be called, and
+     *  OnStopRequest will immediately follow with the same status code.
+     */
+    void resumeAt(in unsigned long long startPos,
+                  in ACString entityID);
+
+    /**
+     * The entity id for this URI. Available after OnStartRequest.
+     * @throw NS_ERROR_NOT_RESUMABLE if this load is not resumable.
+     */
+    readonly attribute ACString entityID;
+};