2 * This file is part of DisOrder.
3 * Copyright (C) 2009, 2013 Richard Kettlewell
5 * This program is free software: you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation, either version 3 of the License, or
8 * (at your option) any later version.
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
15 * You should have received a copy of the GNU General Public License
16 * along with this program. If not, see <http://www.gnu.org/licenses/>.
18 /** @file lib/uaudio-rtp.c
19 * @brief Support for RTP network play backend */
23 #include <sys/socket.h>
26 #include <arpa/inet.h>
27 #include <netinet/in.h>
42 #include "configuration.h"
44 /** @brief Bytes to send per network packet */
45 static int rtp_max_payload
;
47 /** @brief RTP payload type */
48 static int rtp_payload
;
50 /** @brief RTP broadcast/multicast output socket */
51 static int rtp_fd
= -1;
53 /** @brief RTP unicast output socket (IPv4) */
54 static int rtp_fd4
= -1;
56 /** @brief RTP unicast output socket (IPv6) */
57 static int rtp_fd6
= -1;
59 /** @brief RTP SSRC */
60 static uint32_t rtp_id
;
62 /** @brief Base for timestamp */
63 static uint32_t rtp_base
;
65 /** @brief RTP sequence number */
66 static uint16_t rtp_sequence
;
68 /** @brief Network error count
70 * If too many errors occur in too short a time, we give up.
72 static int rtp_errors
;
74 /** @brief RTP mode */
77 #define RTP_BROADCAST 1
78 #define RTP_MULTICAST 2
83 /** @brief A unicast client */
84 struct rtp_recipient
{
85 struct rtp_recipient
*next
;
86 struct sockaddr_storage sa
;
89 /** @brief List of unicast clients */
90 static struct rtp_recipient
*rtp_recipient_list
;
92 /** @brief Mutex protecting data structures */
93 static pthread_mutex_t rtp_lock
= PTHREAD_MUTEX_INITIALIZER
;
95 static const char *const rtp_options
[] = {
97 "rtp-destination-port",
107 static void rtp_get_netconfig(const char *af
,
110 struct netaddress
*na
) {
113 vec
[0] = uaudio_get(af
, NULL
);
114 vec
[1] = uaudio_get(addr
, NULL
);
115 vec
[2] = uaudio_get(port
, NULL
);
119 if(netaddress_parse(na
, 3, vec
))
120 disorder_fatal(0, "invalid RTP address");
123 static void rtp_set_netconfig(const char *af
,
126 const struct netaddress
*na
) {
127 uaudio_set(af
, NULL
);
128 uaudio_set(addr
, NULL
);
129 uaudio_set(port
, NULL
);
134 netaddress_format(na
, &nvec
, &vec
);
136 uaudio_set(af
, vec
[0]);
140 uaudio_set(addr
, vec
[1]);
144 uaudio_set(port
, vec
[2]);
151 static size_t rtp_play(void *buffer
, size_t nsamples
, unsigned flags
) {
152 struct rtp_header header
;
156 if(flags
& (UAUDIO_PAUSE
|UAUDIO_RESUME
))
157 fprintf(stderr
, "rtp_play %zu samples%s%s%s%s\n", nsamples
,
158 flags
& UAUDIO_PAUSE ?
" UAUDIO_PAUSE" : "",
159 flags
& UAUDIO_RESUME ?
" UAUDIO_RESUME" : "",
160 flags
& UAUDIO_PLAYING ?
" UAUDIO_PLAYING" : "",
161 flags
& UAUDIO_PAUSED ?
" UAUDIO_PAUSED" : "");
164 /* We do as much work as possible before checking what time it is */
165 /* Fill out header */
166 header
.vpxcc
= 2 << 6; /* V=2, P=0, X=0, CC=0 */
167 header
.seq
= htons(rtp_sequence
++);
168 header
.ssrc
= rtp_id
;
169 header
.mpt
= rtp_payload
;
170 /* If we've come out of a pause, set the marker bit */
171 if(flags
& UAUDIO_RESUME
)
174 /* Convert samples to network byte order */
175 uint16_t *u
= buffer
, *const limit
= u
+ nsamples
;
181 vec
[0].iov_base
= (void *)&header
;
182 vec
[0].iov_len
= sizeof header
;
183 vec
[1].iov_base
= buffer
;
184 vec
[1].iov_len
= nsamples
* uaudio_sample_size
;
185 const uint32_t timestamp
= uaudio_schedule_sync();
186 header
.timestamp
= htonl(rtp_base
+ (uint32_t)timestamp
);
188 /* We send ~120 packets a second with current arrangements. So if we log
189 * once every 8192 packets we log about once a minute. */
191 if(!(ntohs(header
.seq
) & 8191)
192 && config
->rtp_verbose
)
193 disorder_info("RTP: seq %04"PRIx16
" %08"PRIx32
"+%08"PRIx32
"=%08"PRIx32
" ns %zu%s",
199 flags
& UAUDIO_PAUSED ?
" [paused]" : "");
201 /* If we're paused don't actually end a packet, we just pretend */
202 if(flags
& UAUDIO_PAUSED
) {
203 uaudio_schedule_sent(nsamples
);
206 /* Send stuff to explicitly registerd unicast addresses unconditionally */
207 struct rtp_recipient
*r
;
209 memset(&m
, 0, sizeof m
);
212 pthread_mutex_lock(&rtp_lock
);
213 for(r
= rtp_recipient_list
; r
; r
= r
->next
) {
215 m
.msg_namelen
= r
->sa
.ss_family
== AF_INET ?
216 sizeof(struct sockaddr_in
) : sizeof (struct sockaddr_in6
);
217 sendmsg(r
->sa
.ss_family
== AF_INET ? rtp_fd4
: rtp_fd6
,
218 &m
, MSG_DONTWAIT
|MSG_NOSIGNAL
);
219 // TODO similar error handling to other case?
221 pthread_mutex_unlock(&rtp_lock
);
222 if(rtp_mode
!= RTP_REQUEST
) {
225 written_bytes
= writev(rtp_fd
, vec
, 2);
226 } while(written_bytes
< 0 && errno
== EINTR
);
227 if(written_bytes
< 0) {
228 disorder_error(errno
, "error transmitting audio data");
231 disorder_fatal(0, "too many audio transmission errors");
234 rtp_errors
/= 2; /* gradual decay */
236 /* TODO what can we sensibly do about short writes here? Really that's just
237 * an error and we ought to be using smaller packets. */
238 uaudio_schedule_sent(nsamples
);
242 static void hack_send_buffer_size(int fd
, const char *what
) {
243 int sndbuf
, target_sndbuf
= 131072;
244 socklen_t len
= sizeof sndbuf
;
246 if(getsockopt(fd
, SOL_SOCKET
, SO_SNDBUF
,
248 disorder_fatal(errno
, "error getting SO_SNDBUF on %s socket", what
);
249 if(target_sndbuf
> sndbuf
) {
250 if(setsockopt(fd
, SOL_SOCKET
, SO_SNDBUF
,
251 &target_sndbuf
, sizeof target_sndbuf
) < 0)
252 disorder_error(errno
, "error setting SO_SNDBUF on %s socket to %d",
253 what
, target_sndbuf
);
255 disorder_info("changed socket send buffer size on %socket from %d to %d",
256 what
, sndbuf
, target_sndbuf
);
258 disorder_info("default socket send buffer on %s socket is %d",
262 static void rtp_open(void) {
263 struct addrinfo
*dres
, *sres
;
264 static const int one
= 1;
265 struct netaddress dst
[1], src
[1];
269 mode
= uaudio_get("rtp-mode", "auto");
270 if(!strcmp(mode
, "broadcast")) rtp_mode
= RTP_BROADCAST
;
271 else if(!strcmp(mode
, "multicast")) rtp_mode
= RTP_MULTICAST
;
272 else if(!strcmp(mode
, "unicast")) rtp_mode
= RTP_UNICAST
;
273 else if(!strcmp(mode
, "request")) rtp_mode
= RTP_REQUEST
;
274 else rtp_mode
= RTP_AUTO
;
275 /* Get the source and destination addresses (which might be missing) */
276 rtp_get_netconfig("rtp-destination-af",
278 "rtp-destination-port",
280 rtp_get_netconfig("rtp-source-af",
285 dres
= netaddress_resolve(dst
, 0, IPPROTO_UDP
);
291 sres
= netaddress_resolve(src
, 1, IPPROTO_UDP
);
296 /* _AUTO inspects the destination address and acts accordingly */
297 if(rtp_mode
== RTP_AUTO
) {
299 rtp_mode
= RTP_REQUEST
;
300 else if(multicast(dres
->ai_addr
))
301 rtp_mode
= RTP_MULTICAST
;
305 if(getifaddrs(&ifs
) < 0)
306 disorder_fatal(errno
, "error calling getifaddrs");
308 /* (At least on Darwin) IFF_BROADCAST might be set but ifa_broadaddr
309 * still a null pointer. It turns out that there's a subsequent entry
310 * for he same interface which _does_ have ifa_broadaddr though... */
311 if((ifs
->ifa_flags
& IFF_BROADCAST
)
312 && ifs
->ifa_broadaddr
313 && sockaddr_equal(ifs
->ifa_broadaddr
, dres
->ai_addr
))
318 rtp_mode
= RTP_BROADCAST
;
320 rtp_mode
= RTP_UNICAST
;
323 rtp_max_payload
= atoi(uaudio_get("rtp-max-payload", "-1"));
324 if(rtp_max_payload
< 0)
325 rtp_max_payload
= 1500 - 8/*UDP*/ - 40/*IP*/ - 8/*conservatism*/;
326 /* Create the sockets */
327 if(rtp_mode
!= RTP_REQUEST
) {
328 if((rtp_fd
= socket(dres
->ai_family
,
330 dres
->ai_protocol
)) < 0)
331 disorder_fatal(errno
, "error creating RTP transmission socket");
333 if((rtp_fd4
= socket(AF_INET
, SOCK_DGRAM
, IPPROTO_UDP
)) < 0)
334 disorder_fatal(errno
, "error creating v4 RTP transmission socket");
335 if((rtp_fd6
= socket(AF_INET6
, SOCK_DGRAM
, IPPROTO_UDP
)) < 0)
336 disorder_fatal(errno
, "error creating v6 RTP transmission socket");
337 /* Configure the socket according to the desired mode */
339 case RTP_MULTICAST
: {
340 /* Enable multicast options */
341 const int ttl
= atoi(uaudio_get("multicast-ttl", "1"));
342 const int loop
= !strcmp(uaudio_get("multicast-loop", "yes"), "yes");
343 switch(dres
->ai_family
) {
345 if(setsockopt(rtp_fd
, IPPROTO_IP
, IP_MULTICAST_TTL
,
346 &ttl
, sizeof ttl
) < 0)
347 disorder_fatal(errno
, "error setting IP_MULTICAST_TTL on multicast socket");
348 if(setsockopt(rtp_fd
, IPPROTO_IP
, IP_MULTICAST_LOOP
,
349 &loop
, sizeof loop
) < 0)
350 disorder_fatal(errno
, "error setting IP_MULTICAST_LOOP on multicast socket");
354 if(setsockopt(rtp_fd
, IPPROTO_IPV6
, IPV6_MULTICAST_HOPS
,
355 &ttl
, sizeof ttl
) < 0)
356 disorder_fatal(errno
, "error setting IPV6_MULTICAST_HOPS on multicast socket");
357 if(setsockopt(rtp_fd
, IPPROTO_IP
, IPV6_MULTICAST_LOOP
,
358 &loop
, sizeof loop
) < 0)
359 disorder_fatal(errno
, "error setting IPV6_MULTICAST_LOOP on multicast socket");
363 disorder_fatal(0, "unsupported address family %d", dres
->ai_family
);
365 disorder_info("multicasting on %s TTL=%d loop=%s",
366 format_sockaddr(dres
->ai_addr
), ttl
, loop ?
"yes" : "no");
370 disorder_info("unicasting on %s", format_sockaddr(dres
->ai_addr
));
373 case RTP_BROADCAST
: {
374 if(setsockopt(rtp_fd
, SOL_SOCKET
, SO_BROADCAST
, &one
, sizeof one
) < 0)
375 disorder_fatal(errno
, "error setting SO_BROADCAST on broadcast socket");
376 disorder_info("broadcasting on %s",
377 format_sockaddr(dres
->ai_addr
));
381 disorder_info("will transmit on request");
385 /* Enlarge the socket buffers */
386 if (rtp_fd
!= -1) hack_send_buffer_size(rtp_fd
, "master socket");
387 hack_send_buffer_size(rtp_fd4
, "IPv4 on-demand socket");
388 hack_send_buffer_size(rtp_fd6
, "IPv6 on-demand socket");
389 /* We might well want to set additional broadcast- or multicast-related
391 if(rtp_mode
!= RTP_REQUEST
) {
392 if(sres
&& bind(rtp_fd
, sres
->ai_addr
, sres
->ai_addrlen
) < 0)
393 disorder_fatal(errno
, "error binding broadcast socket to %s",
394 format_sockaddr(sres
->ai_addr
));
395 if(connect(rtp_fd
, dres
->ai_addr
, dres
->ai_addrlen
) < 0)
396 disorder_fatal(errno
, "error connecting broadcast socket to %s",
397 format_sockaddr(dres
->ai_addr
));
399 if(config
->rtp_verbose
)
400 disorder_info("RTP: prepared socket");
403 static void rtp_start(uaudio_callback
*callback
,
405 /* We only support L16 (but we do stereo and mono and will convert sign) */
406 if(uaudio_channels
== 2
408 && uaudio_rate
== 44100)
410 else if(uaudio_channels
== 1
412 && uaudio_rate
== 44100)
415 disorder_fatal(0, "asked for %d/%d/%d 16/44100/1 and 16/44100/2",
416 uaudio_bits
, uaudio_rate
, uaudio_channels
);
417 if(config
->rtp_verbose
)
418 disorder_info("RTP: %d channels %d bits %d Hz payload type %d",
419 uaudio_channels
, uaudio_bits
, uaudio_rate
, rtp_payload
);
420 /* Various fields are required to have random initial values by RFC3550. The
421 * packet contents are highly public so there's no point asking for very
422 * strong randomness. */
423 gcry_create_nonce(&rtp_id
, sizeof rtp_id
);
424 gcry_create_nonce(&rtp_base
, sizeof rtp_base
);
425 gcry_create_nonce(&rtp_sequence
, sizeof rtp_sequence
);
426 if(config
->rtp_verbose
)
427 disorder_info("RTP: id %08"PRIx32
" base %08"PRIx32
" initial seq %08"PRIx16
,
428 rtp_id
, rtp_base
, rtp_sequence
);
430 uaudio_schedule_init();
431 if(config
->rtp_verbose
)
432 disorder_info("RTP: initialized schedule");
433 uaudio_thread_start(callback
,
436 256 / uaudio_sample_size
,
437 (rtp_max_payload
- sizeof(struct rtp_header
))
438 / uaudio_sample_size
,
440 if(config
->rtp_verbose
)
441 disorder_info("RTP: created thread");
444 static void rtp_stop(void) {
445 uaudio_thread_stop();
446 if(rtp_fd
>= 0) { close(rtp_fd
); rtp_fd
= -1; }
447 if(rtp_fd4
>= 0) { close(rtp_fd4
); rtp_fd4
= -1; }
448 if(rtp_fd6
>= 0) { close(rtp_fd6
); rtp_fd6
= -1; }
451 static void rtp_configure(void) {
454 uaudio_set("rtp-mode", config
->rtp_mode
);
455 rtp_set_netconfig("rtp-destination-af",
457 "rtp-destination-port", &config
->broadcast
);
458 rtp_set_netconfig("rtp-source-af",
460 "rtp-source-port", &config
->broadcast_from
);
461 snprintf(buffer
, sizeof buffer
, "%ld", config
->multicast_ttl
);
462 uaudio_set("multicast-ttl", buffer
);
463 uaudio_set("multicast-loop", config
->multicast_loop ?
"yes" : "no");
464 snprintf(buffer
, sizeof buffer
, "%ld", config
->rtp_max_payload
);
465 uaudio_set("rtp-max-payload", buffer
);
466 if(config
->rtp_verbose
)
467 disorder_info("RTP: configured");
470 /** @brief Add an RTP recipient address
471 * @param sa Pointer to recipient address
472 * @return 0 on success, -1 on error
474 int rtp_add_recipient(const struct sockaddr_storage
*sa
) {
475 struct rtp_recipient
*r
;
477 pthread_mutex_lock(&rtp_lock
);
478 for(r
= rtp_recipient_list
;
479 r
&& sockaddrcmp((struct sockaddr
*)sa
,
480 (struct sockaddr
*)&r
->sa
);
486 r
= xmalloc(sizeof *r
);
487 memcpy(&r
->sa
, sa
, sizeof *sa
);
488 r
->next
= rtp_recipient_list
;
489 rtp_recipient_list
= r
;
492 pthread_mutex_unlock(&rtp_lock
);
496 /** @brief Remove an RTP recipient address
497 * @param sa Pointer to recipient address
498 * @return 0 on success, -1 on error
500 int rtp_remove_recipient(const struct sockaddr_storage
*sa
) {
501 struct rtp_recipient
*r
, **rr
;
503 pthread_mutex_lock(&rtp_lock
);
504 for(rr
= &rtp_recipient_list
;
505 (r
= *rr
) && sockaddrcmp((struct sockaddr
*)sa
,
506 (struct sockaddr
*)&r
->sa
);
514 disorder_error(0, "bogus rtp_remove_recipient");
517 pthread_mutex_unlock(&rtp_lock
);
521 const struct uaudio uaudio_rtp
= {
523 .options
= rtp_options
,
526 .activate
= uaudio_thread_activate
,
527 .deactivate
= uaudio_thread_deactivate
,
528 .configure
= rtp_configure
,
529 .flags
= UAUDIO_API_SERVER
,