Help the static analyzer in `handle_ice`

Clang's static analyzer thinks we could be using `hosts` here when it
is NULL.  We probably weren't, but it's easy to see how it could think
so.  We were checking whether `from_addr` matched `ice->addr` three
times, and between the second on third time we might have modified the
`ice->addr`; however we only get there if it matched the second time,
so we could only make it not match at that point and avoid the third
branch.  We can't make it match where it did not before.

We'll simplify the logic a bit here so static analyzers (and humans)
can hopefully see this more readily.

diff --git a/src/switch_rtp.c b/src/switch_rtp.c
index a1a95ff0926efde15e9e319ecfb358b1416c4a38..161f46f7825486bbb3e3d4961b556d0566e43f6a 100644 (file)
--- a/src/switch_rtp.c
+++ b/src/switch_rtp.c
@@ -1056,6 +1056,7 @@ static void handle_ice(switch_rtp_t *rtp_session, switch_rtp_ice_t *ice, void *d
                        char ipbuf[25];
                        switch_sockaddr_t *from_addr = rtp_session->from_addr;
                        switch_socket_t *sock_output = rtp_session->sock_output;
+                       uint8_t hosts_set = 0;
 
                        if (is_rtcp) {
                                from_addr = rtp_session->rtcp_from_addr;
@@ -1078,6 +1079,7 @@ static void handle_ice(switch_rtp_t *rtp_session, switch_rtp_ice_t *ice, void *d
                        switch_stun_packet_attribute_add_xor_binded_address(rpacket, (char *) remote_ip, switch_sockaddr_get_port(from_addr));
 
                        if (!switch_cmp_addr(from_addr, ice->addr)) {
+                               hosts_set++;
                                host = switch_get_addr(buf, sizeof(buf), from_addr);
                                port = switch_sockaddr_get_port(from_addr);
                                host2 = switch_get_addr(buf2, sizeof(buf2), ice->addr);
@@ -1088,7 +1090,7 @@ static void handle_ice(switch_rtp_t *rtp_session, switch_rtp_ice_t *ice, void *d
                                switch_stun_packet_attribute_add_integrity(rpacket, ice->pass);
                                switch_stun_packet_attribute_add_fingerprint(rpacket);
                        } else {
-                               if (!switch_cmp_addr(from_addr, ice->addr)) {
+                               if (hosts_set) {
                                        switch_sockaddr_info_get(&ice->addr, host, SWITCH_UNSPEC, port, 0, rtp_session->pool);
                                        
                                        switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(rtp_session->session), SWITCH_LOG_NOTICE,
@@ -1111,7 +1113,7 @@ static void handle_ice(switch_rtp_t *rtp_session, switch_rtp_ice_t *ice, void *d
 
                        bytes = switch_stun_packet_length(rpacket);
 
-                       if (!ice->rready && (ice->type & ICE_VANILLA) && ice->ice_params && !switch_cmp_addr(from_addr, ice->addr)) {
+                       if (!ice->rready && (ice->type & ICE_VANILLA) && ice->ice_params && hosts_set && !switch_cmp_addr(from_addr, ice->addr)) {
                                int i = 0;
 
                                ice->missed_count = 0;