1 /* GStreamer
2 * Copyright (C) 2017 Matthew Waters <matthew@centricular.com>
3 *
4 * This library is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Library General Public
6 * License as published by the Free Software Foundation; either
7 * version 2 of the License, or (at your option) any later version.
8 *
9 * This library is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * Library General Public License for more details.
13 *
14 * You should have received a copy of the GNU Library General Public
15 * License along with this library; if not, write to the
16 * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
17 * Boston, MA 02110-1301, USA.
18 */
19
20 #ifdef HAVE_CONFIG_H
21 # include "config.h"
22 #endif
23
24 #include "transportreceivebin.h"
25 #include "utils.h"
26
27 /*
28 * ,----------------------------transport_receive_%u---------------------------,
29 * ; (rtp/data) ;
30 * ; ,-nicesrc-, ,-capsfilter-, ,--queue--, ,-dtlssrtpdec-, ,-funnel-, ;
31 * ; ; src o-o sink src o-osink srco-osink rtp_srco-------o sink_0 ; ;
32 * ; '---------' '------------' '---------' ; ; ; src o--o rtp_src
33 * ; ; rtcp_srco---, ,-o sink_1 ; ;
34 * ; ; ; ; ; '--------' ;
35 * ; ; data_srco-, ; ; ,-funnel-, ;
36 * ; (rtcp) '-------------' ; '-+-o sink_0 ; ;
37 * ; ,-nicesrc-, ,-capsfilter-, ,--queue--, ,-dtlssrtpdec-, ; ,-' ; src o--o rtcp_src
38 * ; ; src o-o sink src o-osink srco-osink rtp_srco-+-' ,-o sink_1 ; ;
39 * ; '---------' '------------' '---------' ; ; ; ; '--------' ;
40 * ; ; rtcp_srco-+---' ,-funnel-, ;
41 * ; ; ; '-----o sink_0 ; ;
42 * ; ; data_srco-, ; src o--o data_src
43 * ; '-------------' '-----o sink_1 ; ;
44 * ; '--------' ;
45 * '---------------------------------------------------------------------------'
46 *
47 * Do we really wnat to be *that* permissive in what we accept?
48 *
49 * FIXME: When and how do we want to clear the possibly stored buffers?
50 */
51
52 #define GST_CAT_DEFAULT gst_webrtc_transport_receive_bin_debug
53 GST_DEBUG_CATEGORY_STATIC (GST_CAT_DEFAULT);
54
55 #define transport_receive_bin_parent_class parent_class
56 G_DEFINE_TYPE_WITH_CODE (TransportReceiveBin, transport_receive_bin,
57 GST_TYPE_BIN,
58 GST_DEBUG_CATEGORY_INIT (gst_webrtc_transport_receive_bin_debug,
59 "webrtctransportreceivebin", 0, "webrtctransportreceivebin");
60 );
61
62 static GstStaticPadTemplate rtp_sink_template =
63 GST_STATIC_PAD_TEMPLATE ("rtp_src",
64 GST_PAD_SINK,
65 GST_PAD_ALWAYS,
66 GST_STATIC_CAPS ("application/x-rtp"));
67
68 static GstStaticPadTemplate rtcp_sink_template =
69 GST_STATIC_PAD_TEMPLATE ("rtcp_src",
70 GST_PAD_SINK,
71 GST_PAD_ALWAYS,
72 GST_STATIC_CAPS ("application/x-rtp"));
73
74 static GstStaticPadTemplate data_sink_template =
75 GST_STATIC_PAD_TEMPLATE ("data_src",
76 GST_PAD_SINK,
77 GST_PAD_ALWAYS,
78 GST_STATIC_CAPS_ANY);
79
80 enum
81 {
82 PROP_0,
83 PROP_STREAM,
84 };
85
86 static const gchar *
_receive_state_to_string(ReceiveState state)87 _receive_state_to_string (ReceiveState state)
88 {
89 switch (state) {
90 case RECEIVE_STATE_BLOCK:
91 return "block";
92 case RECEIVE_STATE_DROP:
93 return "drop";
94 case RECEIVE_STATE_PASS:
95 return "pass";
96 default:
97 return "Unknown";
98 }
99 }
100
101 static GstPadProbeReturn
pad_block(GstPad * pad,GstPadProbeInfo * info,TransportReceiveBin * receive)102 pad_block (GstPad * pad, GstPadProbeInfo * info, TransportReceiveBin * receive)
103 {
104 g_mutex_lock (&receive->pad_block_lock);
105 while (receive->receive_state == RECEIVE_STATE_BLOCK) {
106 g_cond_wait (&receive->pad_block_cond, &receive->pad_block_lock);
107 GST_DEBUG_OBJECT (pad, "probe waited. new state %s",
108 _receive_state_to_string (receive->receive_state));
109 }
110
111 g_mutex_unlock (&receive->pad_block_lock);
112
113 return GST_PAD_PROBE_OK;
114 }
115
116 static GstPadProbeReturn
src_probe_cb(GstPad * pad,GstPadProbeInfo * info,TransportReceiveBin * receive)117 src_probe_cb (GstPad * pad, GstPadProbeInfo * info,
118 TransportReceiveBin * receive)
119 {
120 GstPadProbeReturn ret;
121
122 g_mutex_lock (&receive->pad_block_lock);
123
124 g_assert (receive->receive_state != RECEIVE_STATE_BLOCK);
125
126 ret =
127 receive->receive_state ==
128 RECEIVE_STATE_DROP ? GST_PAD_PROBE_DROP : GST_PAD_PROBE_OK;
129
130 g_mutex_unlock (&receive->pad_block_lock);
131
132 return ret;
133 }
134
135 void
transport_receive_bin_set_receive_state(TransportReceiveBin * receive,ReceiveState state)136 transport_receive_bin_set_receive_state (TransportReceiveBin * receive,
137 ReceiveState state)
138 {
139 g_mutex_lock (&receive->pad_block_lock);
140 receive->receive_state = state;
141 GST_DEBUG_OBJECT (receive, "changing receive state to %s",
142 _receive_state_to_string (state));
143 g_cond_signal (&receive->pad_block_cond);
144 g_mutex_unlock (&receive->pad_block_lock);
145 }
146
147 static void
transport_receive_bin_set_property(GObject * object,guint prop_id,const GValue * value,GParamSpec * pspec)148 transport_receive_bin_set_property (GObject * object, guint prop_id,
149 const GValue * value, GParamSpec * pspec)
150 {
151 TransportReceiveBin *receive = TRANSPORT_RECEIVE_BIN (object);
152
153 GST_OBJECT_LOCK (receive);
154 switch (prop_id) {
155 case PROP_STREAM:
156 /* XXX: weak-ref this? */
157 receive->stream = TRANSPORT_STREAM (g_value_get_object (value));
158 break;
159 default:
160 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
161 break;
162 }
163 GST_OBJECT_UNLOCK (receive);
164 }
165
166 static void
transport_receive_bin_get_property(GObject * object,guint prop_id,GValue * value,GParamSpec * pspec)167 transport_receive_bin_get_property (GObject * object, guint prop_id,
168 GValue * value, GParamSpec * pspec)
169 {
170 TransportReceiveBin *receive = TRANSPORT_RECEIVE_BIN (object);
171
172 GST_OBJECT_LOCK (receive);
173 switch (prop_id) {
174 case PROP_STREAM:
175 g_value_set_object (value, receive->stream);
176 break;
177 default:
178 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
179 break;
180 }
181 GST_OBJECT_UNLOCK (receive);
182 }
183
184 static void
transport_receive_bin_finalize(GObject * object)185 transport_receive_bin_finalize (GObject * object)
186 {
187 TransportReceiveBin *receive = TRANSPORT_RECEIVE_BIN (object);
188
189 g_mutex_clear (&receive->pad_block_lock);
190 g_cond_clear (&receive->pad_block_cond);
191
192 G_OBJECT_CLASS (parent_class)->finalize (object);
193 }
194
195 static GstStateChangeReturn
transport_receive_bin_change_state(GstElement * element,GstStateChange transition)196 transport_receive_bin_change_state (GstElement * element,
197 GstStateChange transition)
198 {
199 TransportReceiveBin *receive = TRANSPORT_RECEIVE_BIN (element);
200 GstStateChangeReturn ret = GST_STATE_CHANGE_SUCCESS;
201
202 GST_DEBUG ("changing state: %s => %s",
203 gst_element_state_get_name (GST_STATE_TRANSITION_CURRENT (transition)),
204 gst_element_state_get_name (GST_STATE_TRANSITION_NEXT (transition)));
205
206 switch (transition) {
207 case GST_STATE_CHANGE_NULL_TO_READY:{
208 GstWebRTCDTLSTransport *transport;
209 GstElement *elem, *dtlssrtpdec;
210 GstPad *pad;
211
212 transport = receive->stream->transport;
213 dtlssrtpdec = transport->dtlssrtpdec;
214 pad = gst_element_get_static_pad (dtlssrtpdec, "sink");
215 receive->rtp_block =
216 _create_pad_block (GST_ELEMENT (receive), pad, 0, NULL, NULL);
217 receive->rtp_block->block_id =
218 gst_pad_add_probe (pad, GST_PAD_PROBE_TYPE_ALL_BOTH,
219 (GstPadProbeCallback) pad_block, receive, NULL);
220 gst_object_unref (pad);
221
222 receive->rtp_src_probe_id = gst_pad_add_probe (receive->rtp_src,
223 GST_PAD_PROBE_TYPE_ALL_BOTH, (GstPadProbeCallback) src_probe_cb,
224 receive, NULL);
225
226 transport = receive->stream->rtcp_transport;
227 dtlssrtpdec = transport->dtlssrtpdec;
228 pad = gst_element_get_static_pad (dtlssrtpdec, "sink");
229 receive->rtcp_block =
230 _create_pad_block (GST_ELEMENT (receive), pad, 0, NULL, NULL);
231 receive->rtcp_block->block_id =
232 gst_pad_add_probe (pad, GST_PAD_PROBE_TYPE_ALL_BOTH,
233 (GstPadProbeCallback) pad_block, receive, NULL);
234 gst_object_unref (pad);
235
236 receive->rtcp_src_probe_id = gst_pad_add_probe (receive->rtcp_src,
237 GST_PAD_PROBE_TYPE_ALL_BOTH, (GstPadProbeCallback) src_probe_cb,
238 receive, NULL);
239
240 /* XXX: because nice needs the nicesrc internal main loop running in order
241 * correctly STUN... */
242 /* FIXME: this races with the pad exposure later and may get not-linked */
243 elem = receive->stream->transport->transport->src;
244 gst_element_set_locked_state (elem, TRUE);
245 gst_element_set_state (elem, GST_STATE_PLAYING);
246 elem = receive->stream->rtcp_transport->transport->src;
247 gst_element_set_locked_state (elem, TRUE);
248 gst_element_set_state (elem, GST_STATE_PLAYING);
249 break;
250 }
251 default:
252 break;
253 }
254
255 ret = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);
256 if (ret == GST_STATE_CHANGE_FAILURE)
257 return ret;
258
259 switch (transition) {
260 case GST_STATE_CHANGE_READY_TO_NULL:{
261 GstElement *elem;
262
263 elem = receive->stream->transport->transport->src;
264 gst_element_set_locked_state (elem, FALSE);
265 gst_element_set_state (elem, GST_STATE_NULL);
266 elem = receive->stream->rtcp_transport->transport->src;
267 gst_element_set_locked_state (elem, FALSE);
268 gst_element_set_state (elem, GST_STATE_NULL);
269
270 if (receive->rtp_block)
271 _free_pad_block (receive->rtp_block);
272 receive->rtp_block = NULL;
273
274 if (receive->rtp_src_probe_id)
275 gst_pad_remove_probe (receive->rtp_src, receive->rtp_src_probe_id);
276 receive->rtp_src_probe_id = 0;
277
278 if (receive->rtcp_block)
279 _free_pad_block (receive->rtcp_block);
280 receive->rtcp_block = NULL;
281
282 if (receive->rtcp_src_probe_id)
283 gst_pad_remove_probe (receive->rtcp_src, receive->rtcp_src_probe_id);
284 receive->rtcp_src_probe_id = 0;
285
286 break;
287 }
288 default:
289 break;
290 }
291
292 return ret;
293 }
294
295 static void
rtp_queue_overrun(GstElement * queue,TransportReceiveBin * receive)296 rtp_queue_overrun (GstElement * queue, TransportReceiveBin * receive)
297 {
298 GST_WARNING_OBJECT (receive, "Internal receive queue overrun. Dropping data");
299 }
300
301 static void
transport_receive_bin_constructed(GObject * object)302 transport_receive_bin_constructed (GObject * object)
303 {
304 TransportReceiveBin *receive = TRANSPORT_RECEIVE_BIN (object);
305 GstWebRTCDTLSTransport *transport;
306 GstPad *ghost, *pad;
307 GstElement *capsfilter, *funnel, *queue;
308 GstCaps *caps;
309
310 g_return_if_fail (receive->stream);
311
312 /* link ice src, dtlsrtp together for rtp */
313 transport = receive->stream->transport;
314 gst_bin_add (GST_BIN (receive), GST_ELEMENT (transport->dtlssrtpdec));
315
316 capsfilter = gst_element_factory_make ("capsfilter", NULL);
317 caps = gst_caps_new_empty_simple ("application/x-rtp");
318 g_object_set (capsfilter, "caps", caps, NULL);
319 gst_caps_unref (caps);
320
321 queue = gst_element_factory_make ("queue", NULL);
322 /* FIXME: make this configurable? */
323 g_object_set (queue, "leaky", 2, "max-size-time", (guint64) 0,
324 "max-size-buffers", 0, "max-size-bytes", 5 * 1024 * 1024, NULL);
325 g_signal_connect (queue, "overrun", G_CALLBACK (rtp_queue_overrun), receive);
326
327 gst_bin_add (GST_BIN (receive), GST_ELEMENT (queue));
328 gst_bin_add (GST_BIN (receive), GST_ELEMENT (capsfilter));
329 if (!gst_element_link_pads (capsfilter, "src", queue, "sink"))
330 g_warn_if_reached ();
331
332 if (!gst_element_link_pads (queue, "src", transport->dtlssrtpdec, "sink"))
333 g_warn_if_reached ();
334
335 gst_bin_add (GST_BIN (receive), GST_ELEMENT (transport->transport->src));
336 if (!gst_element_link_pads (GST_ELEMENT (transport->transport->src), "src",
337 GST_ELEMENT (capsfilter), "sink"))
338 g_warn_if_reached ();
339
340 /* link ice src, dtlsrtp together for rtcp */
341 transport = receive->stream->rtcp_transport;
342 gst_bin_add (GST_BIN (receive), GST_ELEMENT (transport->dtlssrtpdec));
343
344 capsfilter = gst_element_factory_make ("capsfilter", NULL);
345 caps = gst_caps_new_empty_simple ("application/x-rtcp");
346 g_object_set (capsfilter, "caps", caps, NULL);
347 gst_caps_unref (caps);
348
349 queue = gst_element_factory_make ("queue", NULL);
350 /* FIXME: make this configurable? */
351 g_object_set (queue, "leaky", 2, "max-size-time", (guint64) 0,
352 "max-size-buffers", 0, "max-size-bytes", 5 * 1024 * 1024, NULL);
353 g_signal_connect (queue, "overrun", G_CALLBACK (rtp_queue_overrun), receive);
354
355 gst_bin_add (GST_BIN (receive), queue);
356 gst_bin_add (GST_BIN (receive), GST_ELEMENT (capsfilter));
357 if (!gst_element_link_pads (capsfilter, "src", queue, "sink"))
358 g_warn_if_reached ();
359
360 if (!gst_element_link_pads (queue, "src", transport->dtlssrtpdec, "sink"))
361 g_warn_if_reached ();
362
363 gst_bin_add (GST_BIN (receive), GST_ELEMENT (transport->transport->src));
364 if (!gst_element_link_pads (GST_ELEMENT (transport->transport->src), "src",
365 GST_ELEMENT (capsfilter), "sink"))
366 g_warn_if_reached ();
367
368 /* create funnel for rtp_src */
369 funnel = gst_element_factory_make ("funnel", NULL);
370 gst_bin_add (GST_BIN (receive), funnel);
371 if (!gst_element_link_pads (receive->stream->transport->dtlssrtpdec,
372 "rtp_src", funnel, "sink_0"))
373 g_warn_if_reached ();
374 if (!gst_element_link_pads (receive->stream->rtcp_transport->dtlssrtpdec,
375 "rtp_src", funnel, "sink_1"))
376 g_warn_if_reached ();
377
378 pad = gst_element_get_static_pad (funnel, "src");
379 receive->rtp_src = gst_ghost_pad_new ("rtp_src", pad);
380
381 gst_element_add_pad (GST_ELEMENT (receive), receive->rtp_src);
382 gst_object_unref (pad);
383
384 /* create funnel for rtcp_src */
385 funnel = gst_element_factory_make ("funnel", NULL);
386 gst_bin_add (GST_BIN (receive), funnel);
387 if (!gst_element_link_pads (receive->stream->transport->dtlssrtpdec,
388 "rtcp_src", funnel, "sink_0"))
389 g_warn_if_reached ();
390 if (!gst_element_link_pads (receive->stream->rtcp_transport->dtlssrtpdec,
391 "rtcp_src", funnel, "sink_1"))
392 g_warn_if_reached ();
393
394 pad = gst_element_get_static_pad (funnel, "src");
395 receive->rtcp_src = gst_ghost_pad_new ("rtcp_src", pad);
396 gst_element_add_pad (GST_ELEMENT (receive), receive->rtcp_src);
397 gst_object_unref (pad);
398
399 /* create funnel for data_src */
400 funnel = gst_element_factory_make ("funnel", NULL);
401 gst_bin_add (GST_BIN (receive), funnel);
402 if (!gst_element_link_pads (receive->stream->transport->dtlssrtpdec,
403 "data_src", funnel, "sink_0"))
404 g_warn_if_reached ();
405 if (!gst_element_link_pads (receive->stream->rtcp_transport->dtlssrtpdec,
406 "data_src", funnel, "sink_1"))
407 g_warn_if_reached ();
408
409 pad = gst_element_get_static_pad (funnel, "src");
410 ghost = gst_ghost_pad_new ("data_src", pad);
411 gst_element_add_pad (GST_ELEMENT (receive), ghost);
412 gst_object_unref (pad);
413
414 G_OBJECT_CLASS (parent_class)->constructed (object);
415 }
416
417 static void
transport_receive_bin_class_init(TransportReceiveBinClass * klass)418 transport_receive_bin_class_init (TransportReceiveBinClass * klass)
419 {
420 GObjectClass *gobject_class = (GObjectClass *) klass;
421 GstElementClass *element_class = (GstElementClass *) klass;
422
423 element_class->change_state = transport_receive_bin_change_state;
424
425 gst_element_class_add_static_pad_template (element_class, &rtp_sink_template);
426 gst_element_class_add_static_pad_template (element_class,
427 &rtcp_sink_template);
428 gst_element_class_add_static_pad_template (element_class,
429 &data_sink_template);
430
431 gst_element_class_set_metadata (element_class, "WebRTC Transport Receive Bin",
432 "Filter/Network/WebRTC", "A bin for webrtc connections",
433 "Matthew Waters <matthew@centricular.com>");
434
435 gobject_class->constructed = transport_receive_bin_constructed;
436 gobject_class->get_property = transport_receive_bin_get_property;
437 gobject_class->set_property = transport_receive_bin_set_property;
438 gobject_class->finalize = transport_receive_bin_finalize;
439
440 g_object_class_install_property (gobject_class,
441 PROP_STREAM,
442 g_param_spec_object ("stream", "Stream",
443 "The TransportStream for this receiveing bin",
444 transport_stream_get_type (),
445 G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY | G_PARAM_STATIC_STRINGS));
446 }
447
448 static void
transport_receive_bin_init(TransportReceiveBin * receive)449 transport_receive_bin_init (TransportReceiveBin * receive)
450 {
451 g_mutex_init (&receive->pad_block_lock);
452 g_cond_init (&receive->pad_block_cond);
453 }
454