res_pjsip: Fix infinite recursion when loading transports from realtime

Attempting to load a transport from realtime was forcing asterisk into an
infinite recursion loop.  The first thing transport_apply did was to do a
sorcery retrieve by id for an existing transport of the same name. For files,
this just returns the previous object from res_sorcery_config's internal
container, if any.  For realtime, the res_sourcery_realtime driver looks in the
database and finds the existing row but now it has to rehydrate it into a
sorcery object which means calling... transport_apply.  And so it goes.

The main issue with loading from realtime (apart from the loop) was that
transport stores structures and pointers directly in the ast_sip_transport
structure instead of the separate ast_transport_state structure.  This patch
separates those items into the ast_sip_transport_state structure.  The pattern
is roughly the same as res_pjsip_outbound_registration.

Although all current usages of ast_sip_transport and ast_sip_transport_state
were modified to use the new ast_sip_get_transport_state API, the original
items are left in ast_sip_transport and kept updated to maintain ABI
compatability for third-party modules.  They are marked as deprecated and
noted that they're now in ast_sip_transport_state.

ASTERISK-25606 #close
Reported-by: Martin Moučka

Change-Id: Ic7a836ea8e786e8def51fe3f8cce855ea54f5f19

1 files changed, 11 insertions, 8 deletions

diff --git a/res/res_pjsip_transport_websocket.c b/res/res_pjsip_transport_websocket.c
index 668129b82..418182870 100644
--- a/res/res_pjsip_transport_websocket.c
+++ b/res/res_pjsip_transport_websocket.c
@@ -275,24 +275,27 @@ static int transport_read(void *data)
 static int get_write_timeout(void)
 {
 	int write_timeout = -1;
-	struct ao2_container *transports;
+	struct ao2_container *transport_states;
 
-	transports = ast_sorcery_retrieve_by_fields(ast_sip_get_sorcery(), "transport", AST_RETRIEVE_FLAG_ALL, NULL);
+	transport_states = ast_sip_get_transport_states();
 
-	if (transports) {
-		struct ao2_iterator it_transports = ao2_iterator_init(transports, 0);
-		struct ast_sip_transport *transport;
+	if (transport_states) {
+		struct ao2_iterator it_transport_states = ao2_iterator_init(transport_states, 0);
+		struct ast_sip_transport_state *transport_state;
 
-		for (; (transport = ao2_iterator_next(&it_transports)); ao2_cleanup(transport)) {
-			if (transport->type != AST_TRANSPORT_WS && transport->type != AST_TRANSPORT_WSS) {
+		for (; (transport_state = ao2_iterator_next(&it_transport_states)); ao2_cleanup(transport_state)) {
+			struct ast_sip_transport *transport;
+			if (transport_state->type != AST_TRANSPORT_WS && transport_state->type != AST_TRANSPORT_WSS) {
 				continue;
 			}
+			transport = ast_sorcery_retrieve_by_id(ast_sip_get_sorcery(), "transport", transport_state->id);
 			ast_debug(5, "Found %s transport with write timeout: %d\n",
 				transport->type == AST_TRANSPORT_WS ? "WS" : "WSS",
 				transport->write_timeout);
 			write_timeout = MAX(write_timeout, transport->write_timeout);
 		}
-		ao2_cleanup(transports);
+		ao2_iterator_destroy(&it_transport_states);
+		ao2_cleanup(transport_states);
 	}
 
 	if (write_timeout < 0) {