Add a new setting to specify the interface the service should be prov…

…ided on.

common.h

@@ -123,6 +123,8 @@ typedef struct {
  char *configfile;
  char *regtype; // The regtype is the service type followed by the protocol, separated by a dot, by
  // default “_raop._tcp.”.
+ char *interface; // a string containg the interface name, or NULL if nothing specified
+ int interface_index; // only valid if the interface string is non-NULL
  double audio_backend_buffer_desired_length; // this will be the length in seconds of the
  // audio backend buffer -- the DAC buffer for ALSA
  double audio_backend_latency_offset; // this will be the offset in seconds to compensate for any

mdns_avahi.c

@@ -204,16 +204,21 @@ static void register_service(AvahiClient *c) {
  return;
 
  int ret;
+ AvahiIfIndex selected_interface;
+ if (config.interface!=NULL)
+ selected_interface = config.interface_index;
+ else
+ selected_interface = AVAHI_IF_UNSPEC;
 #ifdef CONFIG_METADATA
  if (config.metadata_enabled) {
- ret = avahi_entry_group_add_service(group, AVAHI_IF_UNSPEC, AVAHI_PROTO_UNSPEC, 0, name,
+ ret = avahi_entry_group_add_service(group, selected_interface, AVAHI_PROTO_UNSPEC, 0, name,
  config.regtype, NULL, NULL, port,
  MDNS_RECORD_WITH_METADATA, NULL);
  if (ret == 0)
  debug(1, "avahi: request to add \"%s\" service with metadata", config.regtype);
  } else {
 #endif
- ret = avahi_entry_group_add_service(group, AVAHI_IF_UNSPEC, AVAHI_PROTO_UNSPEC, 0, name,
+ ret = avahi_entry_group_add_service(group, selected_interface, AVAHI_PROTO_UNSPEC, 0, name,
  config.regtype, NULL, NULL, port,
  MDNS_RECORD_WITHOUT_METADATA, NULL);
  if (ret == 0)

mdns_tinysvcmdns.c

@@ -70,17 +70,21 @@ static int mdns_tinysvcmdns_register(char *apname, int port) {
 
  // Look for an ipv4/ipv6 non-loopback interface to use as the main one.
  for (ifa = ifalist; ifa != NULL; ifa = ifa->ifa_next) {
- if (!(ifa->ifa_flags & IFF_LOOPBACK) && ifa->ifa_addr && ifa->ifa_addr->sa_family == AF_INET) {
- uint32_t main_ip = ((struct sockaddr_in *)ifa->ifa_addr)->sin_addr.s_addr;
-
- mdnsd_set_hostname(svr, hostname, main_ip); // TTL should be 120 seconds
- break;
- } else if (!(ifa->ifa_flags & IFF_LOOPBACK) && ifa->ifa_addr &&
- ifa->ifa_addr->sa_family == AF_INET6) {
- struct in6_addr *addr = &((struct sockaddr_in6 *)ifa->ifa_addr)->sin6_addr;
-
- mdnsd_set_hostname_v6(svr, hostname, addr); // TTL should be 120 seconds
- break;
+ // only check for the named interface, if specified
+ if ((config.interface==NULL) || (strcmp(config.interface,ifa->ifa_name)==0)) {
+
+ if (!(ifa->ifa_flags & IFF_LOOPBACK) && ifa->ifa_addr && ifa->ifa_addr->sa_family == AF_INET) {
+ uint32_t main_ip = ((struct sockaddr_in *)ifa->ifa_addr)->sin_addr.s_addr;
+
+ mdnsd_set_hostname(svr, hostname, main_ip); // TTL should be 120 seconds
+ break;
+ } else if (!(ifa->ifa_flags & IFF_LOOPBACK) && ifa->ifa_addr &&
+ ifa->ifa_addr->sa_family == AF_INET6) {
+ struct in6_addr *addr = &((struct sockaddr_in6 *)ifa->ifa_addr)->sin6_addr;
+
+ mdnsd_set_hostname_v6(svr, hostname, addr); // TTL should be 120 seconds
+ break;
+ }
  }
  }
 
@@ -92,20 +96,22 @@ static int mdns_tinysvcmdns_register(char *apname, int port) {
  // Skip the first one, it was already added by set_hostname
  for (ifa = ifa->ifa_next; ifa != NULL; ifa = ifa->ifa_next) {
  if (ifa->ifa_flags & IFF_LOOPBACK) // Skip loop-back interfaces
- continue;
-
- switch (ifa->ifa_addr->sa_family) {
- case AF_INET: { // ipv4
- uint32_t ip = ((struct sockaddr_in *)ifa->ifa_addr)->sin_addr.s_addr;
- struct rr_entry *a_e = rr_create_a(create_nlabel(hostname), ip); // TTL should be 120 seconds
- mdnsd_add_rr(svr, a_e);
- } break;
- case AF_INET6: { // ipv6
- struct in6_addr *addr = &((struct sockaddr_in6 *)ifa->ifa_addr)->sin6_addr;
- struct rr_entry *aaaa_e =
- rr_create_aaaa(create_nlabel(hostname), addr); // TTL should be 120 seconds
- mdnsd_add_rr(svr, aaaa_e);
- } break;
+ continue; 
+ // only check for the named interface, if specified
+ if ((config.interface==NULL) || (strcmp(config.interface,ifa->ifa_name)==0)) {
+ switch (ifa->ifa_addr->sa_family) {
+ case AF_INET: { // ipv4
+ uint32_t ip = ((struct sockaddr_in *)ifa->ifa_addr)->sin_addr.s_addr;
+ struct rr_entry *a_e = rr_create_a(create_nlabel(hostname), ip); // TTL should be 120 seconds
+ mdnsd_add_rr(svr, a_e);
+ } break;
+ case AF_INET6: { // ipv6
+ struct in6_addr *addr = &((struct sockaddr_in6 *)ifa->ifa_addr)->sin6_addr;
+ struct rr_entry *aaaa_e =
+ rr_create_aaaa(create_nlabel(hostname), addr); // TTL should be 120 seconds
+ mdnsd_add_rr(svr, aaaa_e);
+ } break;
+ }
  }
  }
 

shairport.c

@@ -38,6 +38,7 @@
 #include <sys/stat.h>
 #include <sys/types.h>
 #include <sys/wait.h>
+#include <net/if.h>
 #include <unistd.h>
 
 #include "config.h"
@@ -490,7 +491,45 @@ int parse_options(int argc, char **argv) {
  die("Invalid playback_mode choice \"%s\". It should be \"stereo\" (default), \"mono\", "
  "\"reverse stereo\", \"both left\", \"both right\"");
  }
-
+
+
+
+
+ /* Get the interface to listen on, if specified Default is all interfaces */
+ /* we keep the interface name and the index */
+
+ if (config_lookup_string(config.cfg, "general.interface", &str))
+ config.interface = strdup(str);
+
+ if (config_lookup_string(config.cfg, "general.interface", &str)) {
+ int specified_interface_found = 0;
+
+ struct if_nameindex *if_ni, *i;
+
+ if_ni = if_nameindex();
+ if (if_ni == NULL) {
+ debug(1,"Can't get a list of interface names.");
+ } else {
+ for (i = if_ni; ! (i->if_index == 0 && i->if_name == NULL); i++) {
+ // printf("%u: %s\n", i->if_index, i->if_name);
+ if (strcmp(i->if_name,str)==0) {
+ config.interface_index = i->if_index;
+ specified_interface_found = 1;
+ }
+ }
+
+ }
+
+ if_freenameindex(if_ni);
+
+ if (specified_interface_found==0) {
+ inform("The mdns service interface \"%s\" was not found, so the setting has been ignored.",config.interface);
+ free(config.interface);
+ config.interface = NULL;
+ config.interface_index = 0; 
+ } 
+ }
+
  /* Get the regtype -- the service type and protocol, separated by a dot. Default is
  * "_raop._tcp" */
  if (config_lookup_string(config.cfg, "general.regtype", &str))
@@ -762,7 +801,6 @@ void shairport_startup_complete(void) {
 const char *pid_file_proc(void) {
 #ifdef HAVE_ASPRINTF
  static char *fn = NULL;
- free(fn);
  asprintf(&fn, "%s/%s.pid", PIDDIR, daemon_pid_file_ident ? daemon_pid_file_ident : "unknown");
 #else
  static char fn[8192];
@@ -777,6 +815,7 @@ const char *pid_file_proc(void) {
 void exit_function() {
  if (config.cfg)
  config_destroy(config.cfg);
+ // probably should be freeing malloc'ed memory here, including strdup-created strings...
 }
 
 int main(int argc, char **argv) {
@@ -1146,7 +1185,10 @@ int main(int argc, char **argv) {
  debug(1, "zeroconf regtype is \"%s\".", config.regtype);
  debug(1, "decoders_supported field is %d.", config.decoders_supported);
  debug(1, "use_apple_decoder is %d.", config.use_apple_decoder);
-
+ if (config.interface)
+ debug(1, "mdns service interface \"%s\" requested.",config.interface);
+ else
+ debug(1, "no special mdns service interface was requested.");
  char *realConfigPath = realpath(config.configfile, NULL);
  if (realConfigPath) {
  debug(1, "configuration file name \"%s\" resolves to \"%s\".", config.configfile,