rtpfunnel: various cleanups

* Organize GstRtpFunnelPad and GstRtpFunnel separately
* Use G_GNUC_UNUSED instead of (void) casts
* Don't call an event "caps"
* Use semicolons after GST_END_TEST (helps gst-indent)
This commit is contained in:
Håvard Graff 2020-02-14 10:08:05 +00:00 committed by GStreamer Merge Bot
parent 9593a3679e
commit 9ba9837058
2 changed files with 412 additions and 28 deletions

View file

@ -20,15 +20,63 @@
* Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
* Boston, MA 02110-1301, USA.
*/
/**
* SECTION:element-rtpfunnel
* @title: rtpfunnel
* @see_also: rtpbasepaylaoder, rtpsession
*
* RTP funnel is basically like a normal funnel with a few added
* functionalities to support bundling.
*
* Bundle is the concept of sending multiple streams in a single RTP session.
* These can be both audio and video streams, and several of both.
* One of the advantages with bundling is that you can get away with fewer
* ports for sending and receiving media. Also the RTCP traffic gets more
* compact if you can report on multiple streams in a single sender/receiver
* report.
*
* One of the reasons for a specialized RTP funnel is that some messages
* coming upstream want to find their way back to the right stream,
* and a normal funnel can't know which of its sinkpads it should send
* these messages to. The RTP funnel achieves this by keeping track of the
* SSRC of each stream on its sinkpad, and then uses the fact that upstream
* events are tagged inside rtpbin with the appropriate SSRC, so that upon
* receiving such an event, the RTP funnel can do a simple lookup for the
* right pad to forward the event to.
*
* A good example here is the KeyUnit event. If several video encoders are
* being bundled together using the RTP funnel, and one of the decoders on
* the receiving side asks for a KeyUnit, typically a RTCP PLI message will
* be sent from the receiver to the sender, and this will be transformed into
* a GstForceKeyUnit event inside GstRTPSession, and sent upstream. The
* RTP funnel can than make sure that this event hits the right encoder based
* on the SSRC embedded in the event.
*
* Another feature of the RTP funnel is that it will mux together TWCC
* (Transport-Wide Congestion Control) sequence-numbers. The point being that
* it should increment "transport-wide", meaning potentially several
* bundled streams. Note that not *all* streams being bundled needs to be
* affected by this. As an example Google WebRTC will use bundle with audio
* and video, but will only use TWCC sequence-numbers for the video-stream(s).
*
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <gst/rtp/gstrtpbuffer.h>
#include "gstrtpfunnel.h"
GST_DEBUG_CATEGORY_STATIC (gst_rtp_funnel_debug);
#define GST_CAT_DEFAULT gst_rtp_funnel_debug
#define TWCC_EXTMAP_STR "http://www.ietf.org/id/draft-holmer-rmcat-transport-wide-cc-extensions-01"
/**************** GstRTPFunnelPad ****************/
struct _GstRtpFunnelPadClass
{
GstPadClass class;
@ -38,8 +86,23 @@ struct _GstRtpFunnelPad
{
GstPad pad;
guint32 ssrc;
gboolean has_twcc;
};
G_DEFINE_TYPE (GstRtpFunnelPad, gst_rtp_funnel_pad, GST_TYPE_PAD);
static void
gst_rtp_funnel_pad_class_init (G_GNUC_UNUSED GstRtpFunnelPadClass * klass)
{
}
static void
gst_rtp_funnel_pad_init (G_GNUC_UNUSED GstRtpFunnelPad * pad)
{
}
/**************** GstRTPFunnel ****************/
enum
{
PROP_0,
@ -48,20 +111,6 @@ enum
#define DEFAULT_COMMON_TS_OFFSET -1
G_DEFINE_TYPE (GstRtpFunnelPad, gst_rtp_funnel_pad, GST_TYPE_PAD);
static void
gst_rtp_funnel_pad_class_init (GstRtpFunnelPadClass * klass)
{
(void) klass;
}
static void
gst_rtp_funnel_pad_init (GstRtpFunnelPad * pad)
{
(void) pad;
}
struct _GstRtpFunnelClass
{
GstElementClass class;
@ -78,6 +127,10 @@ struct _GstRtpFunnel
/* The last pad data was chained on */
GstPad *current_pad;
guint8 twcc_ext_id; /* the negotiated twcc extmap id */
guint16 twcc_seqnum; /* our internal twcc seqnum */
guint twcc_pads; /* numer of sinkpads with negotiated twcc */
/* properties */
gint common_ts_offset;
};
@ -102,7 +155,7 @@ static void
gst_rtp_funnel_send_sticky (GstRtpFunnel * funnel, GstPad * pad)
{
GstEvent *stream_start;
GstEvent *caps;
GstEvent *caps_ev;
if (!funnel->send_sticky_events)
goto done;
@ -113,8 +166,8 @@ gst_rtp_funnel_send_sticky (GstRtpFunnel * funnel, GstPad * pad)
goto done;
}
caps = gst_event_new_caps (funnel->srccaps);
if (caps && !gst_pad_push_event (funnel->srcpad, caps)) {
caps_ev = gst_event_new_caps (funnel->srccaps);
if (caps_ev && !gst_pad_push_event (funnel->srcpad, caps_ev)) {
GST_ERROR_OBJECT (funnel, "Could not push caps");
goto done;
}
@ -146,6 +199,43 @@ done:
return;
}
static void
gst_rtp_funnel_set_twcc_seqnum (GstRtpFunnel * funnel,
GstPad * pad, GstBuffer ** buf)
{
GstRtpFunnelPad *fpad = GST_RTP_FUNNEL_PAD_CAST (pad);
GstRTPBuffer rtp = GST_RTP_BUFFER_INIT;
if (!funnel->twcc_ext_id || !fpad->has_twcc)
return;
*buf = gst_buffer_make_writable (*buf);
if (gst_rtp_buffer_map (*buf, GST_MAP_READWRITE, &rtp)) {
gpointer data;
/* if there already is a twcc-seqnum inside the packet */
if (gst_rtp_buffer_get_extension_onebyte_header (&rtp, funnel->twcc_ext_id,
0, &data, NULL)) {
/* with only one pad, we read the twcc-seqnum instead of writing it */
if (funnel->twcc_pads == 1) {
funnel->twcc_seqnum = GST_READ_UINT16_BE (data);
} else {
GST_WRITE_UINT16_BE (data, funnel->twcc_seqnum);
}
} else {
guint16 seq_be;
GST_WRITE_UINT16_BE (&seq_be, funnel->twcc_seqnum);
gst_rtp_buffer_add_extension_onebyte_header (&rtp, funnel->twcc_ext_id,
&seq_be, 2);
}
}
gst_rtp_buffer_unmap (&rtp);
funnel->twcc_seqnum++;
}
static GstFlowReturn
gst_rtp_funnel_sink_chain_object (GstPad * pad, GstRtpFunnel * funnel,
gboolean is_list, GstMiniObject * obj)
@ -159,11 +249,13 @@ gst_rtp_funnel_sink_chain_object (GstPad * pad, GstRtpFunnel * funnel,
gst_rtp_funnel_send_sticky (funnel, pad);
gst_rtp_funnel_forward_segment (funnel, pad);
if (is_list)
if (is_list) {
res = gst_pad_push_list (funnel->srcpad, GST_BUFFER_LIST_CAST (obj));
else
res = gst_pad_push (funnel->srcpad, GST_BUFFER_CAST (obj));
} else {
GstBuffer *buf = GST_BUFFER_CAST (obj);
gst_rtp_funnel_set_twcc_seqnum (funnel, pad, &buf);
res = gst_pad_push (funnel->srcpad, buf);
}
GST_PAD_STREAM_UNLOCK (funnel->srcpad);
return res;
@ -188,10 +280,55 @@ gst_rtp_funnel_sink_chain (GstPad * pad, GstObject * parent, GstBuffer * buffer)
GST_MINI_OBJECT_CAST (buffer));
}
static void
gst_rtp_funnel_set_twcc_ext_id (GstRtpFunnel * funnel, guint8 twcc_ext_id)
{
gchar *name;
if (funnel->twcc_ext_id == twcc_ext_id)
return;
name = g_strdup_printf ("extmap-%u", twcc_ext_id);
gst_caps_set_simple (funnel->srccaps, name, G_TYPE_STRING, TWCC_EXTMAP_STR,
NULL);
g_free (name);
/* make sure we update the sticky with the new caps */
funnel->send_sticky_events = TRUE;
GST_INFO_OBJECT (funnel, "Setting twcc-ext-id to %u", twcc_ext_id);
funnel->twcc_ext_id = twcc_ext_id;
}
static guint8
_get_extmap_id_for_attribute (const GstStructure * s, const gchar * ext_name)
{
guint i;
guint8 extmap_id = 0;
guint n_fields = gst_structure_n_fields (s);
for (i = 0; i < n_fields; i++) {
const gchar *field_name = gst_structure_nth_field_name (s, i);
if (g_str_has_prefix (field_name, "extmap-")) {
const gchar *str = gst_structure_get_string (s, field_name);
if (str && g_strcmp0 (str, ext_name) == 0) {
gint64 id = g_ascii_strtoll (field_name + 7, NULL, 10);
if (id > 0 && id < 15) {
extmap_id = id;
break;
}
}
}
}
return extmap_id;
}
static gboolean
gst_rtp_funnel_sink_event (GstPad * pad, GstObject * parent, GstEvent * event)
{
GstRtpFunnel *funnel = GST_RTP_FUNNEL_CAST (parent);
GstRtpFunnelPad *fpad = GST_RTP_FUNNEL_PAD_CAST (pad);
gboolean forward = TRUE;
gboolean ret = TRUE;
@ -207,6 +344,7 @@ gst_rtp_funnel_sink_event (GstPad * pad, GstObject * parent, GstEvent * event)
GstCaps *caps;
GstStructure *s;
guint ssrc;
guint8 ext_id;
gst_event_parse_caps (event, &caps);
if (!gst_caps_can_intersect (funnel->srccaps, caps)) {
@ -217,13 +355,18 @@ gst_rtp_funnel_sink_event (GstPad * pad, GstObject * parent, GstEvent * event)
s = gst_caps_get_structure (caps, 0);
if (gst_structure_get_uint (s, "ssrc", &ssrc)) {
GstRtpFunnelPad *fpad = GST_RTP_FUNNEL_PAD_CAST (pad);
fpad->ssrc = ssrc;
GST_DEBUG_OBJECT (pad, "Got ssrc: %u", ssrc);
GST_OBJECT_LOCK (funnel);
g_hash_table_insert (funnel->ssrc_to_pad, GUINT_TO_POINTER (ssrc), pad);
GST_OBJECT_UNLOCK (funnel);
}
ext_id = _get_extmap_id_for_attribute (s, TWCC_EXTMAP_STR);
if (ext_id > 0) {
fpad->has_twcc = TRUE;
funnel->twcc_pads++;
gst_rtp_funnel_set_twcc_ext_id (funnel, ext_id);
}
forward = FALSE;
break;
@ -245,8 +388,7 @@ static gboolean
gst_rtp_funnel_sink_query (GstPad * pad, GstObject * parent, GstQuery * query)
{
GstRtpFunnel *funnel = GST_RTP_FUNNEL_CAST (parent);
gboolean res = FALSE;
(void) funnel;
gboolean res = TRUE;
switch (GST_QUERY_TYPE (query)) {
case GST_QUERY_CAPS:
@ -271,7 +413,20 @@ gst_rtp_funnel_sink_query (GstPad * pad, GstObject * parent, GstQuery * query)
GST_DEBUG_OBJECT (pad, "Answering caps-query with caps: %"
GST_PTR_FORMAT, new_caps);
gst_caps_unref (new_caps);
res = TRUE;
break;
}
case GST_QUERY_ACCEPT_CAPS:
{
GstCaps *caps;
gboolean result;
gst_query_parse_accept_caps (query, &caps);
result = gst_caps_is_subset (caps, funnel->srccaps);
if (!result) {
GST_ERROR_OBJECT (pad,
"caps: %" GST_PTR_FORMAT " were not compatible with: %"
GST_PTR_FORMAT, caps, funnel->srccaps);
}
gst_query_set_accept_caps_result (query, result);
break;
}
default:

View file

@ -22,6 +22,7 @@
*/
#include <gst/check/gstcheck.h>
#include <gst/check/gstharness.h>
#include <gst/rtp/gstrtpbuffer.h>
GST_START_TEST (rtpfunnel_ssrc_demuxing)
{
@ -81,7 +82,8 @@ GST_START_TEST (rtpfunnel_ssrc_demuxing)
gst_harness_teardown (h1);
}
GST_END_TEST
GST_END_TEST;
GST_START_TEST (rtpfunnel_ssrc_downstream_not_leaking_through)
{
GstHarness *h = gst_harness_new_with_padnames ("rtpfunnel",
@ -100,7 +102,8 @@ GST_START_TEST (rtpfunnel_ssrc_downstream_not_leaking_through)
gst_harness_teardown (h);
}
GST_END_TEST
GST_END_TEST;
GST_START_TEST (rtpfunnel_common_ts_offset)
{
GstHarness *h = gst_harness_new_with_padnames ("rtpfunnel",
@ -122,7 +125,8 @@ GST_START_TEST (rtpfunnel_common_ts_offset)
gst_harness_teardown (h);
}
GST_END_TEST
GST_END_TEST;
GST_START_TEST (rtpfunnel_stress)
{
GstHarness *h = gst_harness_new_with_padnames ("rtpfunnel",
@ -173,6 +177,226 @@ GST_START_TEST (rtpfunnel_stress)
GST_END_TEST;
#define TWCC_EXTMAP_STR "http://www.ietf.org/id/draft-holmer-rmcat-transport-wide-cc-extensions-01"
GST_START_TEST (rtpfunnel_twcc_caps)
{
GstHarness *h, *h0, *h1;
GstCaps *caps, *expected_caps;
h = gst_harness_new_with_padnames ("rtpfunnel", NULL, "src");
/* request a sinkpad, set caps with twcc extmap */
h0 = gst_harness_new_with_element (h->element, "sink_0", NULL);
gst_harness_set_src_caps_str (h0, "application/x-rtp, "
"ssrc=(uint)123, extmap-5=" TWCC_EXTMAP_STR "");
/* request a second sinkpad, and verify the extmap is
present in the caps when doing a caps-query downstream */
h1 = gst_harness_new_with_element (h->element, "sink_1", NULL);
caps = gst_pad_query_caps (GST_PAD_PEER (h1->srcpad), NULL);
expected_caps = gst_caps_from_string ("application/x-rtp, "
"extmap-5=" TWCC_EXTMAP_STR "");
fail_unless (gst_caps_is_equal (expected_caps, caps));
gst_caps_unref (caps);
gst_caps_unref (expected_caps);
/* now try and set a different extmap (4) on the other sinkpad,
and verify this does not work */
gst_harness_set_src_caps_str (h1, "application/x-rtp, "
"ssrc=(uint)456, extmap-4=" TWCC_EXTMAP_STR "");
caps = gst_pad_get_current_caps (GST_PAD_PEER (h1->srcpad));
fail_unless (caps == NULL);
/* ...but setting the right extmap (5) will work just fine */
expected_caps = gst_caps_from_string ("application/x-rtp, "
"ssrc=(uint)456, extmap-5=" TWCC_EXTMAP_STR "");
gst_harness_set_src_caps (h1, gst_caps_ref (expected_caps));
caps = gst_pad_get_current_caps (GST_PAD_PEER (h1->srcpad));
fail_unless (gst_caps_is_equal (expected_caps, caps));
gst_caps_unref (caps);
gst_caps_unref (expected_caps);
gst_harness_teardown (h);
gst_harness_teardown (h0);
gst_harness_teardown (h1);
}
GST_END_TEST;
static GstBuffer *
generate_test_buffer (guint seqnum, guint ssrc, guint8 twcc_ext_id)
{
GstBuffer *buf;
GstRTPBuffer rtp = GST_RTP_BUFFER_INIT;
buf = gst_rtp_buffer_new_allocate (0, 0, 0);
GST_BUFFER_PTS (buf) = seqnum * 20 * GST_MSECOND;
GST_BUFFER_DTS (buf) = GST_BUFFER_PTS (buf);
gst_rtp_buffer_map (buf, GST_MAP_READWRITE, &rtp);
gst_rtp_buffer_set_payload_type (&rtp, 100);
gst_rtp_buffer_set_seq (&rtp, seqnum);
gst_rtp_buffer_set_timestamp (&rtp, seqnum * 160);
gst_rtp_buffer_set_ssrc (&rtp, ssrc);
if (twcc_ext_id > 0) {
guint16 data;
GST_WRITE_UINT16_BE (&data, seqnum);
gst_rtp_buffer_add_extension_onebyte_header (&rtp, twcc_ext_id,
&data, sizeof (guint16));
}
gst_rtp_buffer_unmap (&rtp);
return buf;
}
static gint32
get_twcc_seqnum (GstBuffer * buf, guint8 ext_id)
{
GstRTPBuffer rtp = GST_RTP_BUFFER_INIT;
gint32 val = -1;
gpointer data;
gst_rtp_buffer_map (buf, GST_MAP_READ, &rtp);
if (gst_rtp_buffer_get_extension_onebyte_header (&rtp, ext_id,
0, &data, NULL)) {
val = GST_READ_UINT16_BE (data);
}
gst_rtp_buffer_unmap (&rtp);
return val;
}
static guint32
get_ssrc (GstBuffer * buf)
{
guint32 ssrc;
GstRTPBuffer rtp = GST_RTP_BUFFER_INIT;
gst_rtp_buffer_map (buf, GST_MAP_READ, &rtp);
ssrc = gst_rtp_buffer_get_ssrc (&rtp);
gst_rtp_buffer_unmap (&rtp);
return ssrc;
}
GST_START_TEST (rtpfunnel_twcc_passthrough)
{
GstHarness *h, *h0;
GstBuffer *buf;
guint16 offset = 65530;
guint packets = 40;
guint i;
h = gst_harness_new_with_padnames ("rtpfunnel", NULL, "src");
h0 = gst_harness_new_with_element (h->element, "sink_0", NULL);
gst_harness_set_src_caps_str (h0, "application/x-rtp, "
"ssrc=(uint)123, extmap-5=" TWCC_EXTMAP_STR "");
/* push some packets with twcc seqnum */
for (i = 0; i < packets; i++) {
guint16 seqnum = i + offset;
fail_unless_equals_int (GST_FLOW_OK,
gst_harness_push (h0, generate_test_buffer (seqnum, 123, 5)));
}
/* and verify the seqnums stays unchanged through the funnel */
for (i = 0; i < packets; i++) {
guint16 seqnum = i + offset;
buf = gst_harness_pull (h);
fail_unless_equals_int (seqnum, get_twcc_seqnum (buf, 5));
gst_buffer_unref (buf);
}
gst_harness_teardown (h);
gst_harness_teardown (h0);
}
GST_END_TEST;
GST_START_TEST (rtpfunnel_twcc_mux)
{
GstHarness *h, *h0, *h1;
GstBuffer *buf;
h = gst_harness_new_with_padnames ("rtpfunnel", NULL, "src");
h0 = gst_harness_new_with_element (h->element, "sink_0", NULL);
h1 = gst_harness_new_with_element (h->element, "sink_1", NULL);
gst_harness_set_src_caps_str (h0, "application/x-rtp, "
"ssrc=(uint)123, extmap-5=" TWCC_EXTMAP_STR "");
gst_harness_set_src_caps_str (h1, "application/x-rtp, "
"ssrc=(uint)456, extmap-5=" TWCC_EXTMAP_STR "");
/* push buffers on both pads with different twcc-seqnums on them (500 and 60000) */
fail_unless_equals_int (GST_FLOW_OK,
gst_harness_push (h0, generate_test_buffer (500, 123, 5)));
fail_unless_equals_int (GST_FLOW_OK,
gst_harness_push (h1, generate_test_buffer (60000, 321, 5)));
/* verify they are muxed continuously (0 -> 1) */
buf = gst_harness_pull (h);
fail_unless_equals_int (123, get_ssrc (buf));
fail_unless_equals_int (0, get_twcc_seqnum (buf, 5));
gst_buffer_unref (buf);
buf = gst_harness_pull (h);
fail_unless_equals_int (321, get_ssrc (buf));
fail_unless_equals_int (1, get_twcc_seqnum (buf, 5));
gst_buffer_unref (buf);
gst_harness_teardown (h);
gst_harness_teardown (h0);
gst_harness_teardown (h1);
}
GST_END_TEST;
GST_START_TEST (rtpfunnel_twcc_passthrough_then_mux)
{
GstHarness *h, *h0, *h1;
GstBuffer *buf;
guint offset0 = 500;
guint offset1 = 45678;
guint i;
h = gst_harness_new_with_padnames ("rtpfunnel", NULL, "src");
h0 = gst_harness_new_with_element (h->element, "sink_0", NULL);
gst_harness_set_src_caps_str (h0, "application/x-rtp, "
"ssrc=(uint)123, extmap-5=" TWCC_EXTMAP_STR "");
/* push one packet with twcc seqnum 100 on pad0 */
fail_unless_equals_int (GST_FLOW_OK,
gst_harness_push (h0, generate_test_buffer (offset0, 123, 5)));
/* add pad1 to the funnel, also with twcc */
h1 = gst_harness_new_with_element (h->element, "sink_1", NULL);
gst_harness_set_src_caps_str (h1, "application/x-rtp, "
"ssrc=(uint)456, extmap-5=" TWCC_EXTMAP_STR "");
/* push one buffer on both pads, with pad1 starting at a different
offset */
fail_unless_equals_int (GST_FLOW_OK,
gst_harness_push (h0, generate_test_buffer (offset0 + 1, 123, 5)));
fail_unless_equals_int (GST_FLOW_OK,
gst_harness_push (h1, generate_test_buffer (offset1, 321, 5)));
/* and verify the seqnums are continuous for all 3 packets, using
the inital offset from pad0 */
for (i = 0; i < 3; i++) {
guint16 seqnum = i + offset0;
buf = gst_harness_pull (h);
fail_unless_equals_int (seqnum, get_twcc_seqnum (buf, 5));
gst_buffer_unref (buf);
}
gst_harness_teardown (h);
gst_harness_teardown (h0);
gst_harness_teardown (h1);
}
GST_END_TEST;
static Suite *
rtpfunnel_suite (void)
{
@ -187,6 +411,11 @@ rtpfunnel_suite (void)
tcase_add_test (tc_chain, rtpfunnel_stress);
tcase_add_test (tc_chain, rtpfunnel_twcc_caps);
tcase_add_test (tc_chain, rtpfunnel_twcc_passthrough);
tcase_add_test (tc_chain, rtpfunnel_twcc_mux);
tcase_add_test (tc_chain, rtpfunnel_twcc_passthrough_then_mux);
return s;
}