# HG changeset patch
# User Matthew Wild <mwild1@gmail.com>
# Date 1732208527 0
# Node ID 750ff9f579e249bafceb8edfa3d2220143411329
# Parent  f29d15aef6f833002535651f26b825178f7ebb5e
mod_c2s, mod_s2s: Support for queuing callbacks to run in session thread

This allows certain session-specific code that needs to run in the async
context, but is itself triggered outside of that context (e.g. timers), to
be queued.

An example of this is the session destruction code of mod_smacks, when the
hibernation timeout is reached.

diff -r f29d15aef6f8 -r 750ff9f579e2 plugins/mod_c2s.lua
--- a/plugins/mod_c2s.lua	Wed Nov 20 12:08:59 2024 +0000
+++ b/plugins/mod_c2s.lua	Thu Nov 21 17:02:07 2024 +0000
@@ -45,6 +45,7 @@
 local stream_callbacks = { default_ns = "jabber:client" };
 local listener = {};
 local runner_callbacks = {};
+local session_events = {};
 
 local m_tls_params = module:metric(
 	"counter", "encrypted", "",
@@ -76,11 +77,11 @@
 
 function stream_callbacks.streamopened(session, attr)
 	-- run _streamopened in async context
-	session.thread:run({ stream = "opened", attr = attr });
+	session.thread:run({ event = "streamopened", attr = attr });
 end
 
-function stream_callbacks._streamopened(session, attr)
-	local send = session.send;
+function session_events.streamopened(session, event)
+	local send, attr = session.send, event.attr;
 	if not attr.to then
 		session:close{ condition = "improper-addressing",
 			text = "A 'to' attribute is required on stream headers" };
@@ -162,14 +163,19 @@
 
 function stream_callbacks.streamclosed(session, attr)
 	-- run _streamclosed in async context
-	session.thread:run({ stream = "closed", attr = attr });
+	session.thread:run({ event = "streamclosed", attr = attr });
 end
 
-function stream_callbacks._streamclosed(session)
+function session_events.streamclosed(session)
 	session.log("debug", "Received </stream:stream>");
 	session:close(false);
 end
 
+function session_events.callback(session, event)
+	session.log("debug", "Running session callback %s", event.name);
+	event.callback(session, event);
+end
+
 function stream_callbacks.error(session, error, data)
 	if error == "no-stream" then
 		session.log("debug", "Invalid opening stream header (%s)", (data:gsub("^([^\1]+)\1", "{%1}")));
@@ -350,13 +356,11 @@
 		session.stream:reset();
 	end
 
-	session.thread = runner(function (stanza)
-		if st.is_stanza(stanza) then
-			core_process_stanza(session, stanza);
-		elseif stanza.stream == "opened" then
-			stream_callbacks._streamopened(session, stanza.attr);
-		elseif stanza.stream == "closed" then
-			stream_callbacks._streamclosed(session, stanza.attr);
+	session.thread = runner(function (item)
+		if st.is_stanza(item) then
+			core_process_stanza(session, item);
+		else
+			session_events[item.event](session, item);
 		end
 	end, runner_callbacks, session);
 
diff -r f29d15aef6f8 -r 750ff9f579e2 plugins/mod_s2s.lua
--- a/plugins/mod_s2s.lua	Wed Nov 20 12:08:59 2024 +0000
+++ b/plugins/mod_s2s.lua	Thu Nov 21 17:02:07 2024 +0000
@@ -89,6 +89,7 @@
 local sessions = module:shared("sessions");
 
 local runner_callbacks = {};
+local session_events = {};
 
 local listener = {};
 
@@ -469,10 +470,11 @@
 
 function stream_callbacks.streamopened(session, attr)
 	-- run _streamopened in async context
-	session.thread:run({ stream = "opened", attr = attr });
+	session.thread:run({ event = "streamopened", attr = attr });
 end
 
-function stream_callbacks._streamopened(session, attr)
+function session_events.streamopened(session, event)
+	local attr = event.attr;
 	session.version = tonumber(attr.version) or 0;
 	session.had_stream = true; -- Had a stream opened at least once
 
@@ -613,14 +615,19 @@
 	end
 end
 
-function stream_callbacks._streamclosed(session)
+function session_events.streamclosed(session)
 	(session.log or log)("debug", "Received </stream:stream>");
 	session:close(false);
 end
 
+function session_events.callback(session, event)
+	session.log("debug", "Running session callback %s", event.name);
+	event.callback(session, event);
+end
+
 function stream_callbacks.streamclosed(session, attr)
 	-- run _streamclosed in async context
-	session.thread:run({ stream = "closed", attr = attr });
+	session.thread:run({ event = "streamclosed", attr = attr });
 end
 
 -- Some stream conditions indicate a problem on our end, e.g. that we sent
@@ -784,13 +791,11 @@
 local function initialize_session(session)
 	local stream = new_xmpp_stream(session, stream_callbacks, stanza_size_limit);
 
-	session.thread = runner(function (stanza)
-		if st.is_stanza(stanza) then
-			core_process_stanza(session, stanza);
-		elseif stanza.stream == "opened" then
-			stream_callbacks._streamopened(session, stanza.attr);
-		elseif stanza.stream == "closed" then
-			stream_callbacks._streamclosed(session, stanza.attr);
+	session.thread = runner(function (item)
+		if st.is_stanza(item) then
+			core_process_stanza(session, item);
+		else
+			session_events[item.event](session, item);
 		end
 	end, runner_callbacks, session);