From 00c6dfb204c0d591a8ded48d3c23ec2a9d54b50e Mon Sep 17 00:00:00 2001
From: Richard Fuchs <rfuchs@sipwise.com>
Date: Mon, 7 Jun 2021 13:06:51 -0400
Subject: [PATCH] TT#91151 add function to create synthetic SDP

Change-Id: I7c4698a61c380efc8043444e255f8d5a1c7f0c6d
---
 daemon/sdp.c   | 65 +++++++++++++++++++++++++++++++++++++++++++++++++-
 include/call.h |  1 +
 include/sdp.h  |  1 +
 3 files changed, 66 insertions(+), 1 deletion(-)

diff --git a/daemon/sdp.c b/daemon/sdp.c
index 51bc6ede3..3c0131fc4 100644
--- a/daemon/sdp.c
+++ b/daemon/sdp.c
@@ -1798,7 +1798,7 @@ static int print_format_str(GString *s, struct call_media *cm) {
 }
 
 static int print_codec_list(GString *s, struct call_media *media) {
-	if (proto_is_not_rtp(media->protocol))
+	if (!proto_is_rtp(media->protocol))
 		return print_format_str(s, media);
 
 	if (media->codecs.codec_prefs.length == 0)
@@ -2754,6 +2754,69 @@ error:
 	return -1;
 }
 
+int sdp_create(str *out, struct call_monologue *monologue, struct sdp_ng_flags *flags) {
+	if (!monologue->medias.length)
+		return -1; // need at least one media
+
+	// grab first components
+	struct call_media *media = monologue->medias.head->data;
+	if (!media->streams.length)
+		return -1;
+	struct packet_stream *first_ps = media->streams.head->data;
+	if (!first_ps->selected_sfd)
+		return -1;
+
+	GString *s = g_string_new("v=0\r\no=- ");
+
+	// init session params
+	if (!monologue->sdp_session_id)
+		monologue->sdp_session_id = (unsigned long long) rtpe_now.tv_sec << 32 | rtpe_now.tv_usec;
+	if (!monologue->sdp_version)
+		monologue->sdp_version = monologue->sdp_session_id;
+
+	g_string_append_printf(s, "%llu %llu %s %s\r\n", monologue->sdp_session_id, monologue->sdp_version,
+			first_ps->selected_sfd->local_intf->advertised_address.addr.family->rfc_name,
+			sockaddr_print_buf(&first_ps->selected_sfd->local_intf->advertised_address.addr));
+
+	g_string_append_printf(s, "s=%s\r\n", rtpe_config.software_id);
+	g_string_append(s, "t=0 0\r\n");
+
+	for (GList *l = monologue->medias.head; l; l = l->next) {
+		media = l->data;
+		if (!media->streams.length)
+			goto err;
+		GList *rtp_ps_link = media->streams.head;
+		struct packet_stream *rtp_ps = rtp_ps_link->data;
+		if (!rtp_ps->selected_sfd)
+			goto err;
+		if (media->protocol)
+			g_string_append_printf(s, "m=" STR_FORMAT " %i %s",
+					STR_FMT(&media->type),
+					rtp_ps->selected_sfd->socket.local.port,
+					media->protocol->name);
+		else if (media->protocol_str.s)
+			g_string_append_printf(s, "m=" STR_FORMAT " %i " STR_FORMAT,
+					STR_FMT(&media->type),
+					rtp_ps->selected_sfd->socket.local.port,
+					STR_FMT(&media->protocol_str));
+		else
+			goto err;
+		print_codec_list(s, media);
+		g_string_append_printf(s, "\r\nc=%s %s\r\n",
+				rtp_ps->selected_sfd->local_intf->advertised_address.addr.family->rfc_name,
+				sockaddr_print_buf(&rtp_ps->selected_sfd->local_intf->advertised_address.addr));
+		print_sdp_media_section(s, media, NULL, flags, rtp_ps_link, true, false);
+	}
+
+	out->s = s->str;
+	out->len = s->len;
+	g_string_free(s, FALSE);
+	return 0;
+err:
+	g_string_free(s, TRUE);
+	return -1;
+}
+
 int sdp_is_duplicate(GQueue *sessions) {
 	for (GList *l = sessions->head; l; l = l->next) {
 		struct sdp_session *s = l->data;
diff --git a/include/call.h b/include/call.h
index 536be8e0b..0e5bde6ba 100644
--- a/include/call.h
+++ b/include/call.h
@@ -404,6 +404,7 @@ struct call_monologue {
 	GQueue			medias;
 	GHashTable		*media_ids;
 	struct media_player	*player;
+	unsigned long long	sdp_session_id;
 	unsigned long long	sdp_version;
 	str			last_in_sdp;
 	GQueue			last_in_sdp_parsed;
diff --git a/include/sdp.h b/include/sdp.h
index ee1f5cd41..e5ac63fd6 100644
--- a/include/sdp.h
+++ b/include/sdp.h
@@ -24,6 +24,7 @@ void sdp_streams_free(GQueue *);
 void sdp_free(GQueue *sessions);
 int sdp_replace(struct sdp_chopper *, GQueue *, struct call_monologue *, struct sdp_ng_flags *);
 int sdp_is_duplicate(GQueue *sessions);
+int sdp_create(str *out, struct call_monologue *, struct sdp_ng_flags *flags);
 
 struct sdp_chopper *sdp_chopper_new(str *input);
 void sdp_chopper_destroy(struct sdp_chopper *chop);