# HG changeset patch
# User Kim Alvefur <zash@zash.se>
# Date 1504391731 -7200
# Node ID 7c2416a1eb94e58f499828065fa6a5bf1025fe2e
# Parent  4bf60727459b9d12f373b4d0931aeb3eca085e67
mod_mam: Clone stanzas before mutating (thanks waqas) (fixes #961)

diff -r 4bf60727459b -r 7c2416a1eb94 mod_mam/mod_mam.lua
--- a/mod_mam/mod_mam.lua	Wed Aug 30 08:20:41 2017 +0200
+++ b/mod_mam/mod_mam.lua	Sun Sep 03 00:35:31 2017 +0200
@@ -276,15 +276,19 @@
 	local with = jid_bare(c2s and orig_to or orig_from);
 
 	-- Filter out <stanza-id> that claim to be from us
-	stanza:maptags(function (tag)
-		if tag.name == "stanza-id" and tag.attr.xmlns == xmlns_st_id then
-			local by_user, by_host, res = jid_prepped_split(tag.attr.by);
-			if not res and by_host == module.host and by_user == store_user then
-				return nil;
+	if stanza:get_child("stanza-id", xmlns_st_id) then
+		stanza = st.clone(stanza);
+		stanza:maptags(function (tag)
+			if tag.name == "stanza-id" and tag.attr.xmlns == xmlns_st_id then
+				local by_user, by_host, res = jid_prepped_split(tag.attr.by);
+				if not res and by_host == module.host and by_user == store_user then
+					return nil;
+				end
 			end
-		end
-		return tag;
-	end);
+			return tag;
+		end);
+		event.stanza = stanza;
+	end
 
 	-- We store chat messages or normal messages that have a body
 	if not(orig_type == "chat" or (orig_type == "normal" and stanza:get_child("body")) ) then
@@ -308,10 +312,12 @@
 		-- And stash it
 		local ok = archive:append(store_user, nil, stanza, time_now(), with);
 		if ok then
+			local clone_for_other_handlers = st.clone(stanza);
 			local id = ok;
-			stanza:tag("stanza-id", { xmlns = xmlns_st_id, by = store_user.."@"..host, id = id }):up();
+			clone_for_other_handlers:tag("stanza-id", { xmlns = xmlns_st_id, by = store_user.."@"..host, id = id }):up();
+			event.stanza = clone_for_other_handlers;
 			if cleanup then cleanup[store_user] = true; end
-			module:fire_event("archive-message-added", { origin = origin, stanza = stanza, for_user = store_user, id = id });
+			module:fire_event("archive-message-added", { origin = origin, stanza = clone_for_storage, for_user = store_user, id = id });
 		end
 	else
 		log("debug", "Not archiving stanza: %s (prefs)", stanza:top_tag());