chan_pjsip: Add configure check for 'pjsip_get_dest_info' function.

The 'pjsip_get_dest_info' function is used to determine if the signaling transport
of the dialog is secure or not. This function was added in PJSIP 2.3 and does not
exist in earlier versions.

This configure check allows Asterisk to build and run with older versions at the
loss of the 'secure' argument for the PJSIP CHANNEL dialplan function. Usage of
this argument will require upgrading to PJSIP 2.3.

ASTERISK-24665 #close
Reported by: Mark Michelson

Review: https://reviewboard.asterisk.org/r/4329/
........

Merged revisions 430546 from http://svn.asterisk.org/svn/asterisk/branches/13


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@430547 65c4cc65-6c06-0410-ace0-fbb531ad65f3

channels/pjsip/dialplan_functions.c

@@ -592,11 +592,16 @@ static int channel_read_pjsip(struct ast_channel *chan, const char *type, const
 	dlg = channel->session->inv_session->dlg;
 
 	if (!strcmp(type, "secure")) {
+#ifdef HAVE_PJSIP_GET_DEST_INFO
 		pjsip_host_info dest;
 		pj_pool_t *pool = pjsip_endpt_create_pool(ast_sip_get_pjsip_endpoint(), "secure-check", 128, 128);
 		pjsip_get_dest_info(dlg->target, NULL, pool, &dest);
 		snprintf(buf, buflen, "%d", dest.flag & PJSIP_TRANSPORT_SECURE ? 1 : 0);
 		pjsip_endpt_release_pool(ast_sip_get_pjsip_endpoint(), pool);
+#else
+		ast_log(LOG_WARNING, "Asterisk has been built against a version of pjproject which does not have the required functionality to support the 'secure' argument. Please upgrade to version 2.3 or later.\n");
+		return -1;
+#endif
 	} else if (!strcmp(type, "target_uri")) {
 		pjsip_uri_print(PJSIP_URI_IN_REQ_URI, dlg->target, buf, buflen);
 		buf_copy = ast_strdupa(buf);