Issue 10005 - Segfault with missing arguments, plus fix a missing define for SIP INFO channels

git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/1.4@69796 65c4cc65-6c06-0410-ace0-fbb531ad65f3

channels/chan_sip.c

@@ -1579,6 +1579,7 @@ static const struct ast_channel_tech sip_tech_info = {
 	.send_digit_end = sip_senddigit_end,
 	.bridge = ast_rtp_bridge,
 	.send_text = sip_sendtext,
+	.func_channel_read = acf_channel_read,
 };
 
 /**--- some list management macros. **/
@@ -14275,6 +14276,12 @@ static int acf_channel_read(struct ast_channel *chan, char *funcname, char *prep
 	if (strcasecmp(args.param, "rtpqos"))
 		return 0;
 
+	/* Default arguments of audio,all */
+	if (ast_strlen_zero(args.type))
+		args.type = "audio";
+	if (ast_strlen_zero(args.field))
+		args.field = "all";
+
 	memset(buf, 0, buflen);
 	memset(&qos, 0, sizeof(qos));