make mdns-external-avahi a conditional compilation

Makefile.am

@@ -8,7 +8,7 @@ bin_PROGRAMS = shairport-sync
 
 # See below for the flags for the test client program
 
-shairport_sync_SOURCES = shairport.c rtsp.c mdns.c mdns_external.c common.c rtp.c player.c alac.c audio.c loudness.c activity_monitor.c
+shairport_sync_SOURCES = shairport.c rtsp.c mdns.c common.c rtp.c player.c alac.c audio.c loudness.c activity_monitor.c
 
 if BUILD_FOR_FREEBSD
   AM_CXXFLAGS = -I/usr/local/include -Wno-multichar -Wall -Wextra -pthread -DSYSCONFDIR=\"$(sysconfdir)\"
@@ -40,6 +40,10 @@ if USE_TINYSVCMDNS
 shairport_sync_SOURCES += mdns_tinysvcmdns.c tinysvcmdns.c
 endif
 
+if USE_EXTERNAL_MDNS
+shairport_sync_SOURCES += mdns_external.c
+endif
+
 if USE_ALSA
 shairport_sync_SOURCES += audio_alsa.c
 endif

configure.ac

@@ -73,7 +73,6 @@ AC_ARG_WITH([dummy],[  --with-dummy = include the dummy audio back end ],[AC_MSG
 AM_CONDITIONAL([USE_DUMMY], [test "x$with_dummy" = "xyes" ])
 
 AC_ARG_WITH([stdout],[  --with-stdout = include the stdout audio back end ],[ AC_MSG_RESULT(>>Including the stdout audio back end)  AC_DEFINE([CONFIG_STDOUT], 1, [Needed by the compiler.]) ], )
-
 AM_CONDITIONAL([USE_STDOUT], [test "x$with_stdout" = "xyes" ])
 
 AC_ARG_WITH([pipe],[  --with-pipe = include the pipe audio back end ],[ AC_MSG_RESULT(>>Including the pipe audio back end)  AC_DEFINE([CONFIG_PIPE], 1, [Needed by the compiler.]) ], )
@@ -95,6 +94,9 @@ AC_ARG_WITH([freebsd-service],
 [  --with-freebsd-service = install a FreeBSD startup script during a make install], , )
 AM_CONDITIONAL([INSTALL_FREEBSD_SERVICE], [test "x$with_freebsd_service" = "xyes"])
 
+AC_ARG_WITH([external-mdns],[  --with-external-mdns = support the use of 'avahi-publish-service' or 'mDNSPublish' to advertise the service on Bonjour/ZeroConf ],[ AC_MSG_RESULT(>>Including external mdns support)  AC_DEFINE([CONFIG_EXTERNAL_MDNS], 1, [Needed by the compiler.]) ], )
+AM_CONDITIONAL([USE_EXTERNAL_MDNS], [test "x$with_external_mdns" = "xyes" ])
+
 # Add the libconfig package
 if  test "x${with_pkg_config}" = xyes ; then
   PKG_CHECK_MODULES(

mdns.c

@@ -42,7 +42,10 @@ extern mdns_backend mdns_external_dns_sd;
 #ifdef CONFIG_TINYSVCMDNS
 extern mdns_backend mdns_tinysvcmdns;
 #endif
+
+#ifdef CONFIG_EXTERNAL_MDNS
 extern mdns_backend mdns_external_avahi;
+#endif
 
 static mdns_backend *mdns_backends[] = {
 #ifdef CONFIG_AVAHI
@@ -55,7 +58,9 @@ static mdns_backend *mdns_backends[] = {
 #ifdef CONFIG_TINYSVCMDNS
     &mdns_tinysvcmdns,
 #endif
+#ifdef CONFIG_EXTERNAL_MDNS
     &mdns_external_avahi,
+#endif
     NULL};
 
 void mdns_register(void) {