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 resolved
*dres
, *sres
;
266 static const int one
= 1;
267 struct netaddress dst
[1], src
[1];
269 #ifdef IP_MTU_DISCOVER
270 const char *mtu_disc
;
275 mode
= uaudio_get("rtp-mode", "auto");
276 if(!strcmp(mode
, "broadcast")) rtp_mode
= RTP_BROADCAST
;
277 else if(!strcmp(mode
, "multicast")) rtp_mode
= RTP_MULTICAST
;
278 else if(!strcmp(mode
, "unicast")) rtp_mode
= RTP_UNICAST
;
279 else if(!strcmp(mode
, "request")) rtp_mode
= RTP_REQUEST
;
280 else rtp_mode
= RTP_AUTO
;
281 /* Get the source and destination addresses (which might be missing) */
282 rtp_get_netconfig("rtp-destination-af",
284 "rtp-destination-port",
286 rtp_get_netconfig("rtp-source-af",
291 if(netaddress_resolve(dst
, 0, SOCK_DGRAM
, &dres
, &ndres
))
298 if(netaddress_resolve(src
, 0, SOCK_DGRAM
, &sres
, &nsres
))
304 /* _AUTO inspects the destination address and acts accordingly */
305 if(rtp_mode
== RTP_AUTO
) {
307 rtp_mode
= RTP_REQUEST
;
308 else if(multicast(dres
->sa
))
309 rtp_mode
= RTP_MULTICAST
;
313 if(getifaddrs(&ifs
) < 0)
314 disorder_fatal(errno
, "error calling getifaddrs");
316 /* (At least on Darwin) IFF_BROADCAST might be set but ifa_broadaddr
317 * still a null pointer. It turns out that there's a subsequent entry
318 * for he same interface which _does_ have ifa_broadaddr though... */
319 if((ifs
->ifa_flags
& IFF_BROADCAST
)
320 && ifs
->ifa_broadaddr
321 && sockaddr_equal(ifs
->ifa_broadaddr
, dres
->sa
))
326 rtp_mode
= RTP_BROADCAST
;
328 rtp_mode
= RTP_UNICAST
;
331 rtp_max_payload
= atoi(uaudio_get("rtp-max-payload", "-1"));
332 if(rtp_max_payload
< 0)
333 rtp_max_payload
= 1500 - 8/*UDP*/ - 40/*IP*/ - 8/*conservatism*/;
334 /* Create the sockets */
335 if(rtp_mode
!= RTP_REQUEST
) {
336 if((rtp_fd
= socket(dres
->sa
->sa_family
, SOCK_DGRAM
, IPPROTO_UDP
)) < 0)
337 disorder_fatal(errno
, "error creating RTP transmission socket");
339 if((rtp_fd4
= socket(AF_INET
, SOCK_DGRAM
, IPPROTO_UDP
)) < 0)
340 disorder_fatal(errno
, "error creating v4 RTP transmission socket");
341 if((rtp_fd6
= socket(AF_INET6
, SOCK_DGRAM
, IPPROTO_UDP
)) < 0)
342 disorder_fatal(errno
, "error creating v6 RTP transmission socket");
343 /* Configure the socket according to the desired mode */
345 case RTP_MULTICAST
: {
346 /* Enable multicast options */
347 const int ttl
= atoi(uaudio_get("multicast-ttl", "1"));
348 const int loop
= !strcmp(uaudio_get("multicast-loop", "yes"), "yes");
349 switch(dres
->sa
->sa_family
) {
351 if(setsockopt(rtp_fd
, IPPROTO_IP
, IP_MULTICAST_TTL
,
352 &ttl
, sizeof ttl
) < 0)
353 disorder_fatal(errno
, "error setting IP_MULTICAST_TTL on multicast socket");
354 if(setsockopt(rtp_fd
, IPPROTO_IP
, IP_MULTICAST_LOOP
,
355 &loop
, sizeof loop
) < 0)
356 disorder_fatal(errno
, "error setting IP_MULTICAST_LOOP on multicast socket");
360 if(setsockopt(rtp_fd
, IPPROTO_IPV6
, IPV6_MULTICAST_HOPS
,
361 &ttl
, sizeof ttl
) < 0)
362 disorder_fatal(errno
, "error setting IPV6_MULTICAST_HOPS on multicast socket");
363 if(setsockopt(rtp_fd
, IPPROTO_IP
, IPV6_MULTICAST_LOOP
,
364 &loop
, sizeof loop
) < 0)
365 disorder_fatal(errno
, "error setting IPV6_MULTICAST_LOOP on multicast socket");
369 disorder_fatal(0, "unsupported address family %d", dres
->sa
->sa_family
);
371 disorder_info("multicasting on %s TTL=%d loop=%s",
372 format_sockaddr(dres
->sa
), ttl
, loop ?
"yes" : "no");
376 disorder_info("unicasting on %s", format_sockaddr(dres
->sa
));
379 case RTP_BROADCAST
: {
380 if(setsockopt(rtp_fd
, SOL_SOCKET
, SO_BROADCAST
, &one
, sizeof one
) < 0)
381 disorder_fatal(errno
, "error setting SO_BROADCAST on broadcast socket");
382 disorder_info("broadcasting on %s",
383 format_sockaddr(dres
->sa
));
387 disorder_info("will transmit on request");
391 /* Enlarge the socket buffers */
392 if (rtp_fd
!= -1) hack_send_buffer_size(rtp_fd
, "master socket");
393 hack_send_buffer_size(rtp_fd4
, "IPv4 on-demand socket");
394 hack_send_buffer_size(rtp_fd6
, "IPv6 on-demand socket");
395 /* We might well want to set additional broadcast- or multicast-related
397 if(rtp_mode
!= RTP_REQUEST
) {
398 if(sres
&& bind(rtp_fd
, sres
->sa
, sres
->len
) < 0)
399 disorder_fatal(errno
, "error binding broadcast socket to %s",
400 format_sockaddr(sres
->sa
));
401 if(connect(rtp_fd
, dres
->sa
, dres
->len
) < 0)
402 disorder_fatal(errno
, "error connecting broadcast socket to %s",
403 format_sockaddr(dres
->sa
));
405 #ifdef IP_MTU_DISCOVER
406 mtu_disc
= uaudio_get("rtp-mtu-discovery", "default");
408 if(!strcmp(mtu_disc
, "yes")) opt
= IP_PMTUDISC_DO
;
409 else if(!strcmp(mtu_disc
, "no")) opt
= IP_PMTUDISC_DONT
;
411 if(setsockopt(rtp_fd4
, IPPROTO_IP
, IP_MTU_DISCOVER
, &opt
, sizeof opt
))
412 disorder_fatal(errno
, "error setting MTU discovery");
413 if(sres
->sa
->sa_family
== AF_INET
&&
414 setsockopt(rtp_fd
, IPPROTO_IP
, IP_MTU_DISCOVER
, &opt
, sizeof opt
))
415 disorder_fatal(errno
, "error setting MTU discovery");
418 if(config
->rtp_verbose
)
419 disorder_info("RTP: prepared socket");
422 static void rtp_start(uaudio_callback
*callback
,
424 /* We only support L16 (but we do stereo and mono and will convert sign) */
425 if(uaudio_channels
== 2
427 && uaudio_rate
== 44100)
429 else if(uaudio_channels
== 1
431 && uaudio_rate
== 44100)
434 disorder_fatal(0, "asked for %d/%d/%d 16/44100/1 and 16/44100/2",
435 uaudio_bits
, uaudio_rate
, uaudio_channels
);
436 if(config
->rtp_verbose
)
437 disorder_info("RTP: %d channels %d bits %d Hz payload type %d",
438 uaudio_channels
, uaudio_bits
, uaudio_rate
, rtp_payload
);
439 /* Various fields are required to have random initial values by RFC3550. The
440 * packet contents are highly public so there's no point asking for very
441 * strong randomness. */
442 gcry_create_nonce(&rtp_id
, sizeof rtp_id
);
443 gcry_create_nonce(&rtp_base
, sizeof rtp_base
);
444 gcry_create_nonce(&rtp_sequence
, sizeof rtp_sequence
);
445 if(config
->rtp_verbose
)
446 disorder_info("RTP: id %08"PRIx32
" base %08"PRIx32
" initial seq %08"PRIx16
,
447 rtp_id
, rtp_base
, rtp_sequence
);
449 uaudio_schedule_init();
450 if(config
->rtp_verbose
)
451 disorder_info("RTP: initialized schedule");
452 uaudio_thread_start(callback
,
455 256 / uaudio_sample_size
,
456 (rtp_max_payload
- sizeof(struct rtp_header
))
457 / uaudio_sample_size
,
459 if(config
->rtp_verbose
)
460 disorder_info("RTP: created thread");
463 static void rtp_stop(void) {
464 uaudio_thread_stop();
465 if(rtp_fd
>= 0) { close(rtp_fd
); rtp_fd
= -1; }
466 if(rtp_fd4
>= 0) { close(rtp_fd4
); rtp_fd4
= -1; }
467 if(rtp_fd6
>= 0) { close(rtp_fd6
); rtp_fd6
= -1; }
470 static void rtp_configure(void) {
473 uaudio_set("rtp-mode", config
->rtp_mode
);
474 rtp_set_netconfig("rtp-destination-af",
476 "rtp-destination-port", &config
->broadcast
);
477 rtp_set_netconfig("rtp-source-af",
479 "rtp-source-port", &config
->broadcast_from
);
480 snprintf(buffer
, sizeof buffer
, "%ld", config
->multicast_ttl
);
481 uaudio_set("multicast-ttl", buffer
);
482 uaudio_set("multicast-loop", config
->multicast_loop ?
"yes" : "no");
483 snprintf(buffer
, sizeof buffer
, "%ld", config
->rtp_max_payload
);
484 uaudio_set("rtp-max-payload", buffer
);
485 uaudio_set("rtp-mtu-discovery", config
->rtp_mtu_discovery
);
486 if(config
->rtp_verbose
)
487 disorder_info("RTP: configured");
490 /** @brief Add an RTP recipient address
491 * @param sa Pointer to recipient address
492 * @return 0 on success, -1 on error
494 int rtp_add_recipient(const struct sockaddr_storage
*sa
) {
495 struct rtp_recipient
*r
;
497 pthread_mutex_lock(&rtp_lock
);
498 for(r
= rtp_recipient_list
;
499 r
&& sockaddrcmp((struct sockaddr
*)sa
,
500 (struct sockaddr
*)&r
->sa
);
506 r
= xmalloc(sizeof *r
);
507 memcpy(&r
->sa
, sa
, sizeof *sa
);
508 r
->next
= rtp_recipient_list
;
509 rtp_recipient_list
= r
;
512 pthread_mutex_unlock(&rtp_lock
);
516 /** @brief Remove an RTP recipient address
517 * @param sa Pointer to recipient address
518 * @return 0 on success, -1 on error
520 int rtp_remove_recipient(const struct sockaddr_storage
*sa
) {
521 struct rtp_recipient
*r
, **rr
;
523 pthread_mutex_lock(&rtp_lock
);
524 for(rr
= &rtp_recipient_list
;
525 (r
= *rr
) && sockaddrcmp((struct sockaddr
*)sa
,
526 (struct sockaddr
*)&r
->sa
);
534 disorder_error(0, "bogus rtp_remove_recipient");
537 pthread_mutex_unlock(&rtp_lock
);
541 const struct uaudio uaudio_rtp
= {
543 .options
= rtp_options
,
546 .activate
= uaudio_thread_activate
,
547 .deactivate
= uaudio_thread_deactivate
,
548 .configure
= rtp_configure
,
549 .flags
= UAUDIO_API_SERVER
,