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",
108 static void rtp_get_netconfig(const char *af
,
111 struct netaddress
*na
) {
114 vec
[0] = uaudio_get(af
, NULL
);
115 vec
[1] = uaudio_get(addr
, NULL
);
116 vec
[2] = uaudio_get(port
, NULL
);
120 if(netaddress_parse(na
, 3, vec
))
121 disorder_fatal(0, "invalid RTP address");
124 static void rtp_set_netconfig(const char *af
,
127 const struct netaddress
*na
) {
128 uaudio_set(af
, NULL
);
129 uaudio_set(addr
, NULL
);
130 uaudio_set(port
, NULL
);
135 netaddress_format(na
, &nvec
, &vec
);
137 uaudio_set(af
, vec
[0]);
141 uaudio_set(addr
, vec
[1]);
145 uaudio_set(port
, vec
[2]);
152 static size_t rtp_play(void *buffer
, size_t nsamples
, unsigned flags
) {
153 struct rtp_header header
;
157 if(flags
& (UAUDIO_PAUSE
|UAUDIO_RESUME
))
158 fprintf(stderr
, "rtp_play %zu samples%s%s%s%s\n", nsamples
,
159 flags
& UAUDIO_PAUSE ?
" UAUDIO_PAUSE" : "",
160 flags
& UAUDIO_RESUME ?
" UAUDIO_RESUME" : "",
161 flags
& UAUDIO_PLAYING ?
" UAUDIO_PLAYING" : "",
162 flags
& UAUDIO_PAUSED ?
" UAUDIO_PAUSED" : "");
165 /* We do as much work as possible before checking what time it is */
166 /* Fill out header */
167 header
.vpxcc
= 2 << 6; /* V=2, P=0, X=0, CC=0 */
168 header
.seq
= htons(rtp_sequence
++);
169 header
.ssrc
= rtp_id
;
170 header
.mpt
= rtp_payload
;
171 /* If we've come out of a pause, set the marker bit */
172 if(flags
& UAUDIO_RESUME
)
175 /* Convert samples to network byte order */
176 uint16_t *u
= buffer
, *const limit
= u
+ nsamples
;
182 vec
[0].iov_base
= (void *)&header
;
183 vec
[0].iov_len
= sizeof header
;
184 vec
[1].iov_base
= buffer
;
185 vec
[1].iov_len
= nsamples
* uaudio_sample_size
;
186 const uint32_t timestamp
= uaudio_schedule_sync();
187 header
.timestamp
= htonl(rtp_base
+ (uint32_t)timestamp
);
189 /* We send ~120 packets a second with current arrangements. So if we log
190 * once every 8192 packets we log about once a minute. */
192 if(!(ntohs(header
.seq
) & 8191)
193 && config
->rtp_verbose
)
194 disorder_info("RTP: seq %04"PRIx16
" %08"PRIx32
"+%08"PRIx32
"=%08"PRIx32
" ns %zu%s",
200 flags
& UAUDIO_PAUSED ?
" [paused]" : "");
202 /* If we're paused don't actually end a packet, we just pretend */
203 if(flags
& UAUDIO_PAUSED
) {
204 uaudio_schedule_sent(nsamples
);
207 /* Send stuff to explicitly registerd unicast addresses unconditionally */
208 struct rtp_recipient
*r
;
210 memset(&m
, 0, sizeof m
);
213 pthread_mutex_lock(&rtp_lock
);
214 for(r
= rtp_recipient_list
; r
; r
= r
->next
) {
216 m
.msg_namelen
= r
->sa
.ss_family
== AF_INET ?
217 sizeof(struct sockaddr_in
) : sizeof (struct sockaddr_in6
);
218 sendmsg(r
->sa
.ss_family
== AF_INET ? rtp_fd4
: rtp_fd6
,
219 &m
, MSG_DONTWAIT
|MSG_NOSIGNAL
);
220 // TODO similar error handling to other case?
222 pthread_mutex_unlock(&rtp_lock
);
223 if(rtp_mode
!= RTP_REQUEST
) {
226 written_bytes
= writev(rtp_fd
, vec
, 2);
227 } while(written_bytes
< 0 && errno
== EINTR
);
228 if(written_bytes
< 0) {
229 disorder_error(errno
, "error transmitting audio data");
232 disorder_fatal(0, "too many audio transmission errors");
235 rtp_errors
/= 2; /* gradual decay */
237 /* TODO what can we sensibly do about short writes here? Really that's just
238 * an error and we ought to be using smaller packets. */
239 uaudio_schedule_sent(nsamples
);
243 static void hack_send_buffer_size(int fd
, const char *what
) {
244 int sndbuf
, target_sndbuf
= 131072;
245 socklen_t len
= sizeof sndbuf
;
247 if(getsockopt(fd
, SOL_SOCKET
, SO_SNDBUF
,
249 disorder_fatal(errno
, "error getting SO_SNDBUF on %s socket", what
);
250 if(target_sndbuf
> sndbuf
) {
251 if(setsockopt(fd
, SOL_SOCKET
, SO_SNDBUF
,
252 &target_sndbuf
, sizeof target_sndbuf
) < 0)
253 disorder_error(errno
, "error setting SO_SNDBUF on %s socket to %d",
254 what
, target_sndbuf
);
256 disorder_info("changed socket send buffer size on %socket from %d to %d",
257 what
, sndbuf
, target_sndbuf
);
259 disorder_info("default socket send buffer on %s socket is %d",
263 static void rtp_open(void) {
264 struct addrinfo
*dres
, *sres
;
265 static const int one
= 1;
266 struct netaddress dst
[1], src
[1];
268 #ifdef IP_MTU_DISCOVER
269 const char *mtu_disc
;
274 mode
= uaudio_get("rtp-mode", "auto");
275 if(!strcmp(mode
, "broadcast")) rtp_mode
= RTP_BROADCAST
;
276 else if(!strcmp(mode
, "multicast")) rtp_mode
= RTP_MULTICAST
;
277 else if(!strcmp(mode
, "unicast")) rtp_mode
= RTP_UNICAST
;
278 else if(!strcmp(mode
, "request")) rtp_mode
= RTP_REQUEST
;
279 else rtp_mode
= RTP_AUTO
;
280 /* Get the source and destination addresses (which might be missing) */
281 rtp_get_netconfig("rtp-destination-af",
283 "rtp-destination-port",
285 rtp_get_netconfig("rtp-source-af",
290 dres
= netaddress_resolve(dst
, 0, IPPROTO_UDP
);
296 sres
= netaddress_resolve(src
, 1, IPPROTO_UDP
);
301 /* _AUTO inspects the destination address and acts accordingly */
302 if(rtp_mode
== RTP_AUTO
) {
304 rtp_mode
= RTP_REQUEST
;
305 else if(multicast(dres
->ai_addr
))
306 rtp_mode
= RTP_MULTICAST
;
310 if(getifaddrs(&ifs
) < 0)
311 disorder_fatal(errno
, "error calling getifaddrs");
313 /* (At least on Darwin) IFF_BROADCAST might be set but ifa_broadaddr
314 * still a null pointer. It turns out that there's a subsequent entry
315 * for he same interface which _does_ have ifa_broadaddr though... */
316 if((ifs
->ifa_flags
& IFF_BROADCAST
)
317 && ifs
->ifa_broadaddr
318 && sockaddr_equal(ifs
->ifa_broadaddr
, dres
->ai_addr
))
323 rtp_mode
= RTP_BROADCAST
;
325 rtp_mode
= RTP_UNICAST
;
328 rtp_max_payload
= atoi(uaudio_get("rtp-max-payload", "-1"));
329 if(rtp_max_payload
< 0)
330 rtp_max_payload
= 1500 - 8/*UDP*/ - 40/*IP*/ - 8/*conservatism*/;
331 /* Create the sockets */
332 if(rtp_mode
!= RTP_REQUEST
) {
333 if((rtp_fd
= socket(dres
->ai_family
,
335 dres
->ai_protocol
)) < 0)
336 disorder_fatal(errno
, "error creating RTP transmission socket");
338 if((rtp_fd4
= socket(AF_INET
, SOCK_DGRAM
, IPPROTO_UDP
)) < 0)
339 disorder_fatal(errno
, "error creating v4 RTP transmission socket");
340 if((rtp_fd6
= socket(AF_INET6
, SOCK_DGRAM
, IPPROTO_UDP
)) < 0)
341 disorder_fatal(errno
, "error creating v6 RTP transmission socket");
342 /* Configure the socket according to the desired mode */
344 case RTP_MULTICAST
: {
345 /* Enable multicast options */
346 const int ttl
= atoi(uaudio_get("multicast-ttl", "1"));
347 const int loop
= !strcmp(uaudio_get("multicast-loop", "yes"), "yes");
348 switch(dres
->ai_family
) {
350 if(setsockopt(rtp_fd
, IPPROTO_IP
, IP_MULTICAST_TTL
,
351 &ttl
, sizeof ttl
) < 0)
352 disorder_fatal(errno
, "error setting IP_MULTICAST_TTL on multicast socket");
353 if(setsockopt(rtp_fd
, IPPROTO_IP
, IP_MULTICAST_LOOP
,
354 &loop
, sizeof loop
) < 0)
355 disorder_fatal(errno
, "error setting IP_MULTICAST_LOOP on multicast socket");
359 if(setsockopt(rtp_fd
, IPPROTO_IPV6
, IPV6_MULTICAST_HOPS
,
360 &ttl
, sizeof ttl
) < 0)
361 disorder_fatal(errno
, "error setting IPV6_MULTICAST_HOPS on multicast socket");
362 if(setsockopt(rtp_fd
, IPPROTO_IP
, IPV6_MULTICAST_LOOP
,
363 &loop
, sizeof loop
) < 0)
364 disorder_fatal(errno
, "error setting IPV6_MULTICAST_LOOP on multicast socket");
368 disorder_fatal(0, "unsupported address family %d", dres
->ai_family
);
370 disorder_info("multicasting on %s TTL=%d loop=%s",
371 format_sockaddr(dres
->ai_addr
), ttl
, loop ?
"yes" : "no");
375 disorder_info("unicasting on %s", format_sockaddr(dres
->ai_addr
));
378 case RTP_BROADCAST
: {
379 if(setsockopt(rtp_fd
, SOL_SOCKET
, SO_BROADCAST
, &one
, sizeof one
) < 0)
380 disorder_fatal(errno
, "error setting SO_BROADCAST on broadcast socket");
381 disorder_info("broadcasting on %s",
382 format_sockaddr(dres
->ai_addr
));
386 disorder_info("will transmit on request");
390 /* Enlarge the socket buffers */
391 if (rtp_fd
!= -1) hack_send_buffer_size(rtp_fd
, "master socket");
392 hack_send_buffer_size(rtp_fd4
, "IPv4 on-demand socket");
393 hack_send_buffer_size(rtp_fd6
, "IPv6 on-demand socket");
394 /* We might well want to set additional broadcast- or multicast-related
396 if(rtp_mode
!= RTP_REQUEST
) {
397 if(sres
&& bind(rtp_fd
, sres
->ai_addr
, sres
->ai_addrlen
) < 0)
398 disorder_fatal(errno
, "error binding broadcast socket to %s",
399 format_sockaddr(sres
->ai_addr
));
400 if(connect(rtp_fd
, dres
->ai_addr
, dres
->ai_addrlen
) < 0)
401 disorder_fatal(errno
, "error connecting broadcast socket to %s",
402 format_sockaddr(dres
->ai_addr
));
404 #ifdef IP_MTU_DISCOVER
405 mtu_disc
= uaudio_get("rtp-mtu-discovery", "default");
407 if(!strcmp(mtu_disc
, "yes")) opt
= IP_PMTUDISC_DO
;
408 else if(!strcmp(mtu_disc
, "no")) opt
= IP_PMTUDISC_DONT
;
410 if(setsockopt(rtp_fd4
, IPPROTO_IP
, IP_MTU_DISCOVER
, &opt
, sizeof opt
))
411 disorder_fatal(errno
, "error setting MTU discovery");
412 if(sres
->ai_family
== AF_INET
&&
413 setsockopt(rtp_fd
, IPPROTO_IP
, IP_MTU_DISCOVER
, &opt
, sizeof opt
))
414 disorder_fatal(errno
, "error setting MTU discovery");
417 if(config
->rtp_verbose
)
418 disorder_info("RTP: prepared socket");
421 static void rtp_start(uaudio_callback
*callback
,
423 /* We only support L16 (but we do stereo and mono and will convert sign) */
424 if(uaudio_channels
== 2
426 && uaudio_rate
== 44100)
428 else if(uaudio_channels
== 1
430 && uaudio_rate
== 44100)
433 disorder_fatal(0, "asked for %d/%d/%d 16/44100/1 and 16/44100/2",
434 uaudio_bits
, uaudio_rate
, uaudio_channels
);
435 if(config
->rtp_verbose
)
436 disorder_info("RTP: %d channels %d bits %d Hz payload type %d",
437 uaudio_channels
, uaudio_bits
, uaudio_rate
, rtp_payload
);
438 /* Various fields are required to have random initial values by RFC3550. The
439 * packet contents are highly public so there's no point asking for very
440 * strong randomness. */
441 gcry_create_nonce(&rtp_id
, sizeof rtp_id
);
442 gcry_create_nonce(&rtp_base
, sizeof rtp_base
);
443 gcry_create_nonce(&rtp_sequence
, sizeof rtp_sequence
);
444 if(config
->rtp_verbose
)
445 disorder_info("RTP: id %08"PRIx32
" base %08"PRIx32
" initial seq %08"PRIx16
,
446 rtp_id
, rtp_base
, rtp_sequence
);
448 uaudio_schedule_init();
449 if(config
->rtp_verbose
)
450 disorder_info("RTP: initialized schedule");
451 uaudio_thread_start(callback
,
454 256 / uaudio_sample_size
,
455 (rtp_max_payload
- sizeof(struct rtp_header
))
456 / uaudio_sample_size
,
458 if(config
->rtp_verbose
)
459 disorder_info("RTP: created thread");
462 static void rtp_stop(void) {
463 uaudio_thread_stop();
464 if(rtp_fd
>= 0) { close(rtp_fd
); rtp_fd
= -1; }
465 if(rtp_fd4
>= 0) { close(rtp_fd4
); rtp_fd4
= -1; }
466 if(rtp_fd6
>= 0) { close(rtp_fd6
); rtp_fd6
= -1; }
469 static void rtp_configure(void) {
472 uaudio_set("rtp-mode", config
->rtp_mode
);
473 rtp_set_netconfig("rtp-destination-af",
475 "rtp-destination-port", &config
->broadcast
);
476 rtp_set_netconfig("rtp-source-af",
478 "rtp-source-port", &config
->broadcast_from
);
479 snprintf(buffer
, sizeof buffer
, "%ld", config
->multicast_ttl
);
480 uaudio_set("multicast-ttl", buffer
);
481 uaudio_set("multicast-loop", config
->multicast_loop ?
"yes" : "no");
482 snprintf(buffer
, sizeof buffer
, "%ld", config
->rtp_max_payload
);
483 uaudio_set("rtp-max-payload", buffer
);
484 uaudio_set("rtp-mtu-discovery", config
->rtp_mtu_discovery
);
485 if(config
->rtp_verbose
)
486 disorder_info("RTP: configured");
489 /** @brief Add an RTP recipient address
490 * @param sa Pointer to recipient address
491 * @return 0 on success, -1 on error
493 int rtp_add_recipient(const struct sockaddr_storage
*sa
) {
494 struct rtp_recipient
*r
;
496 pthread_mutex_lock(&rtp_lock
);
497 for(r
= rtp_recipient_list
;
498 r
&& sockaddrcmp((struct sockaddr
*)sa
,
499 (struct sockaddr
*)&r
->sa
);
505 r
= xmalloc(sizeof *r
);
506 memcpy(&r
->sa
, sa
, sizeof *sa
);
507 r
->next
= rtp_recipient_list
;
508 rtp_recipient_list
= r
;
511 pthread_mutex_unlock(&rtp_lock
);
515 /** @brief Remove an RTP recipient address
516 * @param sa Pointer to recipient address
517 * @return 0 on success, -1 on error
519 int rtp_remove_recipient(const struct sockaddr_storage
*sa
) {
520 struct rtp_recipient
*r
, **rr
;
522 pthread_mutex_lock(&rtp_lock
);
523 for(rr
= &rtp_recipient_list
;
524 (r
= *rr
) && sockaddrcmp((struct sockaddr
*)sa
,
525 (struct sockaddr
*)&r
->sa
);
533 disorder_error(0, "bogus rtp_remove_recipient");
536 pthread_mutex_unlock(&rtp_lock
);
540 const struct uaudio uaudio_rtp
= {
542 .options
= rtp_options
,
545 .activate
= uaudio_thread_activate
,
546 .deactivate
= uaudio_thread_deactivate
,
547 .configure
= rtp_configure
,
548 .flags
= UAUDIO_API_SERVER
,