osmux: add osmux_snprintf

Useful for debugging purposes. Modify also examples to use it.

examples/osmux-test-input.c

@@ -71,7 +71,11 @@ static struct osmo_rtp_handle *rtp;
 
 static void osmux_deliver(struct msgb *batch_msg, void *data)
 {
-	printf("sending batch (len=%d)\n", batch_msg->len);
+	char buf[1024];
+
+	osmux_snprintf(buf, sizeof(buf), batch_msg);
+	LOGP(DOSMUX_TEST, LOGL_DEBUG, "sending batch (len=%d): %s\n",
+		batch_msg->len, buf);
 	osmo_dgram_send(conn, batch_msg);
 }
 
@@ -131,8 +135,6 @@ int read_cb(struct osmo_dgram *conn)
 	struct rtp_hdr *rtph;
 	int ret, ccid;
 
-	LOGP(DOSMUX_TEST, LOGL_DEBUG, "received message from datagram\n");
-
 	msg = msgb_alloc(RTP_MSGB_SIZE, "OSMUX/test");
 	if (msg == NULL) {
 		LOGP(DOSMUX_TEST, LOGL_ERROR, "cannot allocate message\n");
@@ -154,6 +156,11 @@ int read_cb(struct osmo_dgram *conn)
 	if (rtph->payload_type == RTP_PT_AMR)
 		amr_write(msg);
 
+	char buf[1024];
+
+	osmo_rtp_snprintf(buf, sizeof(buf), msg);
+	LOGP(DOSMUX_TEST, LOGL_DEBUG, "received RTP (len=%d): %s\n", msg->len, buf);
+
 	ccid = get_ccid(rtph->ssrc);
 	if (ccid < 0)
 		register_ccid(rtph->ssrc);

examples/osmux-test-output.c

@@ -78,7 +78,7 @@ static void tx_cb(struct msgb *msg, void *data)
 	char buf[4096];
 
 	osmo_rtp_snprintf(buf, sizeof(buf), msg);
-	printf("sending: %s\n", buf);
+	LOGP(DOSMUX_TEST, LOGL_DEBUG, "sending: %s\n", buf);
 	osmo_dgram_send(conn, msg);
 
 	amr_write(msg);
@@ -102,10 +102,12 @@ int read_cb(struct osmo_dgram *conn)
 		return -1;
 	}
 
-	LOGP(DOSMUX_TEST, LOGL_DEBUG, "received OSMUX message (len=%d)\n", msg->len);
+	char buf[1024];
+	osmux_snprintf(buf, sizeof(buf), msg);
+	LOGP(DOSMUX_TEST, LOGL_DEBUG, "received OSMUX message (len=%d) %s\n",
+		msg->len, buf);
 
 	while((osmuxh = osmux_xfrm_output_pull(msg)) != NULL) {
-		printf("tx_sched\n");
 		osmux_xfrm_output(osmuxh, &h_output, &list);
 		osmux_tx_sched(&list, tx_cb, NULL);
 	}

include/osmocom/netif/osmux.h

@@ -56,11 +56,15 @@ struct osmux_out_handle {
 	uint32_t rtp_timestamp;
 };
 
+struct osmux_hdr *osmux_get_hdr(struct msgb *msg);
+
 static inline uint8_t *osmux_get_payload(struct osmux_hdr *osmuxh)
 {
 	return (uint8_t *)osmuxh + sizeof(struct osmux_hdr);
 }
 
+int osmux_snprintf(char *buf, size_t size, struct msgb *msg);
+
 void osmux_xfrm_input_init(struct osmux_in_handle *h);
 
 int osmux_xfrm_input(struct osmux_in_handle *h, struct msgb *msg, int ccid);

src/osmux.c

@@ -34,6 +34,23 @@
 
 static void *osmux_ctx;
 
+struct osmux_hdr *osmux_get_hdr(struct msgb *msg)
+{
+	struct osmux_hdr *osmuxh = (struct osmux_hdr *)msg->data;
+
+	if (msg->len < sizeof(struct osmux_hdr)) {
+		DEBUGPC(DLMUX, "received OSMUX frame too short (len = %d)\n",
+			msg->len);
+		return NULL;
+	}
+	return osmuxh;
+}
+
+static uint32_t osmux_get_payload_len(struct osmux_hdr *osmuxh)
+{
+	return osmo_amr_bytes(osmuxh->amr_ft) * (osmuxh->ctr+1);
+}
+
 struct osmux_hdr *osmux_xfrm_output_pull(struct msgb *msg)
 {
 	struct osmux_hdr *osmuxh = NULL;
@@ -505,3 +522,78 @@ void osmux_xfrm_output_init(struct osmux_out_handle *h)
 	h->rtp_seq = (uint16_t)random();
 	h->rtp_timestamp = (uint32_t)random();
 }
+
+#define SNPRINTF_BUFFER_SIZE(ret, size, len, offset)	\
+	size += ret;					\
+	if (ret > len)					\
+		ret = len;				\
+	offset += ret;					\
+	len -= ret;
+
+static int osmux_snprintf_header(char *buf, size_t size, struct osmux_hdr *osmuxh)
+{
+	int ret;
+	int len = size, offset = 0;
+
+	ret = snprintf(buf, len, "OSMUX seq=%03u ccid=%03u "
+				 "ft=%01u ctr=%01u "
+				 "amr_f=%01u amr_q=%01u "
+				 "amr_ft=%02u amr_cmr=%02u ",
+			osmuxh->seq, osmuxh->circuit_id,
+			osmuxh->ft, osmuxh->ctr,
+			osmuxh->amr_f, osmuxh->amr_q,
+			osmuxh->amr_ft, osmuxh->amr_cmr);
+	SNPRINTF_BUFFER_SIZE(ret, size, len, offset);
+
+	return offset;
+}
+
+static int osmux_snprintf_payload(char *buf, size_t size,
+				  const uint8_t *payload, int payload_len)
+{
+	int ret, i;
+	int len = size, offset = 0;
+
+	for (i=0; i<payload_len; i++) {
+		ret = snprintf(buf+offset, len, "%02x ", payload[i]);
+		SNPRINTF_BUFFER_SIZE(ret, size, len, offset);
+	}
+
+	ret = snprintf(buf+offset, len, "]\n");
+	SNPRINTF_BUFFER_SIZE(ret, size, len, offset);
+
+	return offset;
+}
+
+
+int osmux_snprintf(char *buf, size_t size, struct msgb *msg)
+{
+	int ret;
+	unsigned int offset = 0;
+	int msg_len = msg->len, len = size;
+	struct osmux_hdr *osmuxh = (struct osmux_hdr *)msg->data;
+	int this_len;
+
+	while (msg_len > 0) {
+		this_len = sizeof(struct osmux_hdr) +
+			   osmux_get_payload_len(osmuxh);
+
+		ret = osmux_snprintf_header(buf+offset, size, osmuxh);
+		if (ret < 0)
+			break;
+		SNPRINTF_BUFFER_SIZE(ret, size, len, offset);
+
+		ret = osmux_snprintf_payload(buf+offset, size,
+					     osmux_get_payload(osmuxh),
+					     osmux_get_payload_len(osmuxh));
+		if (ret < 0)
+			break;
+		SNPRINTF_BUFFER_SIZE(ret, size, len, offset);
+
+		msg_len -= this_len;
+
+		osmuxh = (struct osmux_hdr *)((uint8_t *)msg->data + this_len);
+	}
+
+	return offset;
+}