From 476a922ad4d50b05a95e43c20c4a2b8b6a98a78f Mon Sep 17 00:00:00 2001
From: Daniel-Constantin Mierla <miconda@gmail.com>
Date: Wed, 17 Jan 2018 22:37:10 +0100
Subject: [PATCH] core: udp server - cast printed debug chars to unsigned

- reported by GH #1403

(cherry picked from commit 64a391a2408b1d34569947f8b028915ec3462e6d)
---
 src/core/udp_server.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/core/udp_server.c b/src/core/udp_server.c
index b88d3d8f513..3d54c5a9a66 100644
--- a/src/core/udp_server.c
+++ b/src/core/udp_server.c
@@ -479,7 +479,7 @@ int udp_rcv_loop()
 				if(isprint(buf[i])) {
 					printbuf[j++] = buf[i];
 				} else {
-					l = snprintf(printbuf+j, 6, " %02X ", buf[i]);
+					l = snprintf(printbuf+j, 6, " %02X ", (unsigned char)buf[i]);
 					if(l<0 || l>=6) {
 						LM_ERR("print buffer building failed (%d/%d/%d)\n",
 								l, j, i);