The original Quake 2 sources as originally released under the GPL license on December 21, 2001.

null/snddma_null.c

@@ -0,0 +1,28 @@
+
+// snddma_null.c
+// all other sound mixing is portable
+
+#include "../client/client.h"
+#include "../client/snd_loc.h"
+
+qboolean SNDDMA_Init(void)
+{
+	return false;
+}
+
+int	SNDDMA_GetDMAPos(void)
+{
+	return 0;
+}
+
+void SNDDMA_Shutdown(void)
+{
+}
+
+void SNDDMA_BeginPainting (void)
+{
+}
+
+void SNDDMA_Submit(void)
+{
+}