Add support for UDP multicast

This change extends the UDP audio device syntax to accept strings like

   udp:239.0.0.1:7355

This allows Direwolf to decode an audio stream sent to a multicast group address.
This commit is contained in:
Mike Playle 2019-04-01 13:03:47 +01:00
parent a1e2d1c3a8
commit fde780f110
1 changed files with 36 additions and 2 deletions

38
audio.c
View File

@ -385,9 +385,23 @@ int audio_open (struct audio_s *pa)
return -1;
}
char mcaddr[20];
unsigned port = DEFAULT_UDP_AUDIO_PORT;
int is_multicast = 0;
if (sscanf(audio_in_name, "udp:%[0-9.]:%d", mcaddr, &port)==2) {
is_multicast = 1;
} else if (sscanf(audio_in_name, "udp:%d", &port)==1) {
is_multicast = 0;
} else {
text_color_set(DW_COLOR_ERROR);
dw_printf ("Couldn't parse address '%s'\n", audio_in_name);
return -1;
}
memset((char *) &si_me, 0, sizeof(si_me));
si_me.sin_family = AF_INET;
si_me.sin_port = htons((short)atoi(audio_in_name+4));
si_me.sin_port = htons(port);
si_me.sin_addr.s_addr = htonl(INADDR_ANY);
//Bind to the socket
@ -396,7 +410,27 @@ int audio_open (struct audio_s *pa)
dw_printf ("Couldn't bind socket, errno %d\n", errno);
return -1;
}
}
if (is_multicast) {
struct ip_mreq mreq;
if(!inet_aton(mcaddr, &mreq.imr_multiaddr)) {
text_color_set(DW_COLOR_ERROR);
dw_printf ("Couldn't parse multicast address %s\n", mcaddr);
return -1;
}
mreq.imr_interface.s_addr = htonl(INADDR_ANY);
if (setsockopt(adev[a].udp_sock, IPPROTO_IP, IP_ADD_MEMBERSHIP,
&mreq, sizeof(mreq))==-1) {
text_color_set(DW_COLOR_ERROR);
dw_printf ("Couldn't add multicast group, errno %d\n", errno);
return -1;
}
}
}
adev[a].inbuf_size_in_bytes = SDR_UDP_BUF_MAXLEN;
break;