From 4acb6d6e34e78553a80edd49512b7925e8b86cb3 Mon Sep 17 00:00:00 2001
From: Thomas Ries <tries@gmx.net>
Date: Sun, 20 Mar 2005 10:35:59 +0000
Subject: [PATCH] - when allocating local ports for RTP relaying, do this   in
 a round-robin way over the available port range.

---
 ChangeLog            |  2 ++
 src/rtpproxy_relay.c | 21 +++++++++++++++++++--
 2 files changed, 21 insertions(+), 2 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index 8c1aab3..370323e 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,7 @@
 0.5.11
 ======
+  20-Mar-2005:  - when allocating local ports for RTP relaying, do this
+                  in a round-robin way over the available port range.
    1-Mar-2005:  - working on running siproxd in front of a routing device
                   and NOT on the firewall itself.
   19-Feb-2005:  - more work on new libosip API
diff --git a/src/rtpproxy_relay.c b/src/rtpproxy_relay.c
index 8316ac0..cd6cc78 100644
--- a/src/rtpproxy_relay.c
+++ b/src/rtpproxy_relay.c
@@ -389,7 +389,9 @@ int rtp_relay_start_fwd (osip_call_id_t *callid, char *client_id,
                          int media_stream_no, struct in_addr local_ipaddr,
                          int *local_port, struct in_addr remote_ipaddr,
                          int remote_port) {
-   int i, j;
+   static int prev_used_port = 0;
+   int num_ports;
+   int i2, i, j;
    int sock, port;
    int freeidx;
    int sts=STS_SUCCESS;
@@ -526,7 +528,20 @@ int rtp_relay_start_fwd (osip_call_id_t *callid, char *client_id,
    /* find a local port number to use and bind to it */
    sock=0;
    port=0;
-   for (i=configuration.rtp_port_low; i<=configuration.rtp_port_high; i+=2) {
+//   for (i=configuration.rtp_port_low; i<=configuration.rtp_port_high; i+=2) {
+
+DEBUGC(DBCLASS_RTP,"*****a prev_used_port=%i",prev_used_port);
+   if ((prev_used_port < configuration.rtp_port_low) ||
+       (prev_used_port > configuration.rtp_port_high)) {
+      prev_used_port = configuration.rtp_port_high;
+   }
+
+   num_ports = configuration.rtp_port_high - configuration.rtp_port_low + 1;
+   for (i2 = (prev_used_port - configuration.rtp_port_low + 1);
+        i2 < (num_ports + prev_used_port - configuration.rtp_port_low + 1);
+        i2 += 2) {
+      i = (i2%num_ports) + configuration.rtp_port_low;
+DEBUGC(DBCLASS_RTP,"***** i=%i, i2=%i",i,i2);
       for (j=0; j<RTPPROXY_SIZE; j++) {
          /* check if port already in use */
          if ((memcmp(&rtp_proxytable[j].local_ipaddr,
@@ -542,6 +557,8 @@ int rtp_relay_start_fwd (osip_call_id_t *callid, char *client_id,
          if (sock) break;
       }
    } /* for i */
+   prev_used_port = port;
+DEBUGC(DBCLASS_RTP,"*****z prev_used_port=%i",prev_used_port);
 
    DEBUGC(DBCLASS_RTP,"rtp_relay_start_fwd: addr=%s, port=%i, sock=%i "
           "freeidx=%i", utils_inet_ntoa(local_ipaddr), port, sock, freeidx);