From 555c0c738be4441867f1f5f1c0e4983bc553af35 Mon Sep 17 00:00:00 2001
From: Mike Brady <mikebrady@eircom.net>
Date: Sun, 16 Apr 2017 17:09:59 +0100
Subject: [PATCH] Fix off-by-one error in enumatering UDP ports in the
 port_range. Make the error message a little more useful.

---
 rtp.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/rtp.c b/rtp.c
index 921da780..af98b349 100644
--- a/rtp.c
+++ b/rtp.c
@@ -562,13 +562,13 @@ static int bind_port(int ip_family, const char *self_ip_address, uint32_t scope_
 #endif
 
   } while ((ret < 0) && (errno == EADDRINUSE) && (desired_port != 0) &&
-           (desired_port++ < config.udp_port_base + config.udp_port_range));
+           (++desired_port < config.udp_port_base + config.udp_port_range));
 
   // debug(1,"UDP port chosen: %d.",desired_port);
 
   if (ret < 0) {
     close(local_socket);
-    die("error: could not bind a UDP port!");
+    die("error: could not bind a UDP port! Check the udp_port_range is large enough (>= 10) or check for restrictive firewall settings or a bad router!");
   }
 
   int sport;