From 3526ca5cb5f5a960ae0b10e8f0e2187353228b60 Mon Sep 17 00:00:00 2001
From: Travis Cross <tc@traviscross.com>
Date: Wed, 16 Jul 2014 00:25:56 +0000
Subject: [PATCH] Allow setting threshold for RTP auto adjust

If we see a certain number of RTP packets from a host and port other
than was negotiated, we adjust to send our RTP to that host and port.
Traditionally we've waited for 10 packets.  This commit makes the
threshold adjustable by setting the channel variable
`rtp_auto_adjust_threshold` to any positive value less than 2^16.
---
 src/switch_rtp.c | 27 ++++++++++++++++++++++++++-
 1 file changed, 26 insertions(+), 1 deletion(-)

diff --git a/src/switch_rtp.c b/src/switch_rtp.c
index de6a238852..a1a95ff092 100644
--- a/src/switch_rtp.c
+++ b/src/switch_rtp.c
@@ -301,6 +301,7 @@ struct switch_rtp {
 	rtcp_msg_t *rtcp_recv_msg_p;
 
 	uint32_t autoadj_window;
+	uint32_t autoadj_threshold;
 	uint32_t autoadj_tally;
 
 	srtp_ctx_t *send_ctx[2];
@@ -4112,7 +4113,19 @@ SWITCH_DECLARE(void) switch_rtp_set_flags(switch_rtp_t *rtp_session, switch_rtp_
 
 			if (i == SWITCH_RTP_FLAG_AUTOADJ) {
 				rtp_session->autoadj_window = 20;
+				rtp_session->autoadj_threshold = 10;
 				rtp_session->autoadj_tally = 0;
+				if (rtp_session->session) {
+					switch_channel_t *channel = switch_core_session_get_channel(rtp_session->session);
+					const char *x = switch_channel_get_variable(channel, "rtp_auto_adjust_threshold");
+					if (x && *x) {
+						int xn = atoi(x);
+						if (xn > 0 && xn <= 65535) {
+							rtp_session->autoadj_window = xn*2;
+							rtp_session->autoadj_threshold = xn;
+						}
+					}
+				}
 				rtp_flush_read_buffer(rtp_session, SWITCH_RTP_FLUSH_ONCE);
 			} else if (i == SWITCH_RTP_FLAG_NOBLOCK && rtp_session->sock_input) {
 				switch_socket_opt_set(rtp_session->sock_input, SWITCH_SO_NONBLOCK, TRUE);
@@ -4145,7 +4158,19 @@ SWITCH_DECLARE(void) switch_rtp_set_flag(switch_rtp_t *rtp_session, switch_rtp_f
 		reset_jitter_seq(rtp_session);
 	} else if (flag == SWITCH_RTP_FLAG_AUTOADJ) {
 		rtp_session->autoadj_window = 20;
+		rtp_session->autoadj_threshold = 10;
 		rtp_session->autoadj_tally = 0;
+		if (rtp_session->session) {
+			switch_channel_t *channel = switch_core_session_get_channel(rtp_session->session);
+			const char *x = switch_channel_get_variable(channel, "rtp_auto_adjust_threshold");
+			if (x && *x) {
+				int xn = atoi(x);
+				if (xn > 0 && xn <= 65535) {
+					rtp_session->autoadj_window = xn*2;
+					rtp_session->autoadj_threshold = xn;
+				}
+			}
+		}
 		rtp_flush_read_buffer(rtp_session, SWITCH_RTP_FLUSH_ONCE);
 		if (rtp_session->jb) {
 			stfu_n_reset(rtp_session->jb);
@@ -5583,7 +5608,7 @@ static int rtp_common_read(switch_rtp_t *rtp_session, switch_payload_t *payload_
 
 		if (bytes && rtp_session->flags[SWITCH_RTP_FLAG_AUTOADJ] && switch_sockaddr_get_port(rtp_session->from_addr)) {
 			if (!switch_cmp_addr(rtp_session->from_addr, rtp_session->remote_addr)) {
-				if (++rtp_session->autoadj_tally >= 10) {
+				if (++rtp_session->autoadj_tally >= rtp_session->autoadj_threshold) {
 					const char *err;
 					uint32_t old = rtp_session->remote_port;
 					const char *tx_host;