diff --git a/daemon/call_interfaces.c b/daemon/call_interfaces.c
index 70d5e3ac7..cc43d08e7 100644
--- a/daemon/call_interfaces.c
+++ b/daemon/call_interfaces.c
@@ -2543,7 +2543,7 @@ static const char *call_offer_answer_ng(ng_command_ctx_t *ctx, const char* addr)
 	sdp = call_str_cpy(&flags.sdp);
 
 	errstr = "Failed to parse SDP";
-	if (sdp_parse(&sdp, &parsed, &flags))
+	if (!sdp_parse(&sdp, &parsed, &flags))
 		goto out;
 
 	if (flags.loop_protect && sdp_is_duplicate(&parsed)) {
@@ -2554,7 +2554,7 @@ static const char *call_offer_answer_ng(ng_command_ctx_t *ctx, const char* addr)
 	}
 
 	errstr = "Incomplete SDP specification";
-	if (sdp_streams(&parsed, &streams, &flags))
+	if (!sdp_streams(&parsed, &streams, &flags))
 		goto out;
 
 	// SDP fragments for trickle ICE must always operate on an existing call
@@ -4040,10 +4040,10 @@ const char *call_publish_ng(ng_command_ctx_t *ctx, const char *addr) {
 
 	sdp_in = call_str_cpy(&flags.sdp);
 
-	if (sdp_parse(&sdp_in, &parsed, &flags))
+	if (!sdp_parse(&sdp_in, &parsed, &flags))
 		return "Failed to parse SDP";
 
-	if (sdp_streams(&parsed, &streams, &flags))
+	if (!sdp_streams(&parsed, &streams, &flags))
 		return "Incomplete SDP specification";
 
 	if (trickle_ice_update(ctx->ngbuf, call, &flags, &streams))
@@ -4200,10 +4200,10 @@ const char *call_subscribe_answer_ng(ng_command_ctx_t *ctx) {
 	if (!call)
 		return "Unknown call-ID";
 
-	if (sdp_parse(&flags.sdp, &parsed, &flags))
+	if (!sdp_parse(&flags.sdp, &parsed, &flags))
 		return "Failed to parse SDP";
 
-	if (sdp_streams(&parsed, &streams, &flags))
+	if (!sdp_streams(&parsed, &streams, &flags))
 		return "Incomplete SDP specification";
 
 	if (trickle_ice_update(ctx->ngbuf, call, &flags, &streams))
diff --git a/daemon/janus.c b/daemon/janus.c
index c78750c78..980c8a467 100644
--- a/daemon/janus.c
+++ b/daemon/janus.c
@@ -854,9 +854,9 @@ static const char *janus_videoroom_configure(struct websocket_message *wm, struc
 		g_auto(sdp_streams_q) streams = TYPED_GQUEUE_INIT;
 		call_ng_flags_init(&flags, OP_PUBLISH);
 		*retcode = 512;
-		if (sdp_parse(&sdp_in, &parsed, &flags))
+		if (!sdp_parse(&sdp_in, &parsed, &flags))
 			return "Failed to parse SDP";
-		if (sdp_streams(&parsed, &streams, &flags))
+		if (!sdp_streams(&parsed, &streams, &flags))
 			return "Incomplete SDP specification";
 
 		ml = janus_get_monologue(handle->id, call, call_get_or_create_monologue);
@@ -967,11 +967,11 @@ static const char *janus_videoroom_start(struct websocket_message *wm, struct ja
 	g_auto(sdp_streams_q) streams = TYPED_GQUEUE_INIT;
 	call_ng_flags_init(&flags, OP_PUBLISH);
 	*retcode = 512;
-	if (sdp_parse(&sdp_in, &parsed, &flags))
+	if (!sdp_parse(&sdp_in, &parsed, &flags))
 		return "Failed to parse SDP";
 
 	*retcode = 512;
-	if (sdp_streams(&parsed, &streams, &flags))
+	if (!sdp_streams(&parsed, &streams, &flags))
 		return "Incomplete SDP specification";
 
 	*retcode = 456;
diff --git a/daemon/sdp.c b/daemon/sdp.c
index da655db1e..2ed3a2985 100644
--- a/daemon/sdp.c
+++ b/daemon/sdp.c
@@ -1298,7 +1298,7 @@ static bool parse_attribute(struct sdp_attribute *a) {
 	return ret;
 }
 
-int sdp_parse(str *body, sdp_sessions_q *sessions, const sdp_ng_flags *flags) {
+bool sdp_parse(str *body, sdp_sessions_q *sessions, const sdp_ng_flags *flags) {
 	str b;
 	struct sdp_session *session = NULL;
 	struct sdp_media *media = NULL;
@@ -1485,12 +1485,12 @@ new_session:
 		adj_s->len = b.s - adj_s->s;
 	}
 
-	return 0;
+	return true;
 
 error:
 	ilog(LOG_WARNING, "Error parsing SDP at offset %zu: %s", (size_t) (b.s - body->s), errstr);
 	sdp_sessions_clear(sessions);
-	return -1;
+	return false;
 }
 
 static void attr_free(struct sdp_attribute *p) {
@@ -1883,7 +1883,7 @@ static void sdp_attr_append_other(sdp_attr_q *dst, struct sdp_attributes *src) {
 }
 
 /* XXX split this function up */
-int sdp_streams(const sdp_sessions_q *sessions, sdp_streams_q *streams, sdp_ng_flags *flags) {
+bool sdp_streams(const sdp_sessions_q *sessions, sdp_streams_q *streams, sdp_ng_flags *flags) {
 	struct sdp_session *session;
 	struct sdp_media *media;
 	struct stream_params *sp;
@@ -2104,12 +2104,12 @@ next:
 		}
 	}
 
-	return 0;
+	return true;
 
 error:
 	ilog(LOG_WARNING, "Failed to extract streams from SDP: %s", errstr);
 	g_free(sp);
-	return -1;
+	return false;
 }
 
 void sdp_streams_clear(sdp_streams_q *q) {
diff --git a/include/sdp.h b/include/sdp.h
index 3ac9c473b..504d61017 100644
--- a/include/sdp.h
+++ b/include/sdp.h
@@ -44,8 +44,8 @@ void sdp_attr_free(struct sdp_attr *);
 sdp_origin *sdp_orig_dup(const sdp_origin *orig);
 void sdp_orig_free(sdp_origin *o);
 
-int sdp_parse(str *body, sdp_sessions_q *sessions, const sdp_ng_flags *);
-int sdp_streams(const sdp_sessions_q *sessions, sdp_streams_q *streams, sdp_ng_flags *);
+bool sdp_parse(str *body, sdp_sessions_q *sessions, const sdp_ng_flags *);
+bool sdp_streams(const sdp_sessions_q *sessions, sdp_streams_q *streams, sdp_ng_flags *);
 void sdp_streams_clear(sdp_streams_q *);
 void sdp_sessions_clear(sdp_sessions_q *sessions);
 int sdp_is_duplicate(sdp_sessions_q *sessions);