Make sound card support (Alsa) optional

src/libmobile/Makefile.am

@@ -7,6 +7,10 @@ libmobile_a_SOURCES = \
 	call.c \
 	main_mobile.c
 
+if HAVE_ALSA
+AM_CPPFLAGS += -DHAVE_ALSA
+endif
+
 if HAVE_SDR
 AM_CPPFLAGS += -DHAVE_SDR
 endif

src/libmobile/sender.c

@@ -115,12 +115,18 @@ int sender_create(sender_t *sender, int kanal, double sendefrequenz, double empf
 		} else
 #endif
 		{
+#ifdef HAVE_ALSA
 			sender->audio_open = sound_open;
 			sender->audio_start = sound_start;
 			sender->audio_close = sound_close;
 			sender->audio_read = sound_read;
 			sender->audio_write = sound_write;
 			sender->audio_get_tosend = sound_get_tosend;
+#else
+			PDEBUG(DSENDER, DEBUG_ERROR, "No sound card support compiled in!\n");
+			rc = -ENOTSUP;
+			goto error;
+#endif
 		}
 	}
 

src/libmobile/sender.h

@@ -1,4 +1,6 @@
+#ifdef HAVE_ALSA
 #include "../libsound/sound.h"
+#endif
 #ifdef HAVE_SDR
 #include "../libsdr/sdr.h"
 #endif