support multiple sound drivers, add sdl

sndout.c

@@ -0,0 +1,80 @@
+/*
+ * (C) notaz, 2013
+ *
+ * This work is licensed under the terms of any of these licenses
+ * (at your option):
+ *  - GNU GPL, version 2 or later.
+ *  - GNU LGPL, version 2.1 or later.
+ *  - MAME license.
+ * See the COPYING file in the top-level directory.
+ */
+
+#include <stdio.h>
+#include <string.h>
+
+#include "linux/sndout_oss.h"
+#include "sndout_sdl.h"
+#include "sndout.h"
+
+static int sndout_null_init(void)
+{
+	return 0;
+}
+
+static void sndout_null_exit(void)
+{
+}
+
+static int sndout_null_start(int rate, int stereo)
+{
+	return 0;
+}
+
+static void sndout_null_stop(void)
+{
+}
+
+static void sndout_null_wait(void)
+{
+}
+
+static int sndout_null_write_nb(const void *data, int bytes)
+{
+	return bytes;
+}
+
+#define SNDOUT_DRIVER(name) { \
+	#name, \
+	sndout_##name##_init, \
+	sndout_##name##_exit, \
+	sndout_##name##_start, \
+	sndout_##name##_stop, \
+	sndout_##name##_wait, \
+	sndout_##name##_write_nb, \
+}
+
+static struct sndout_driver sndout_avail[] =
+{
+#ifdef HAVE_SDL
+	SNDOUT_DRIVER(sdl),
+#endif
+#ifdef HAVE_OSS
+	SNDOUT_DRIVER(oss),
+#endif
+	SNDOUT_DRIVER(null)
+};
+
+struct sndout_driver sndout_current;
+
+void sndout_init(void)
+{
+	int i;
+
+	for (i = 0; i < sizeof(sndout_avail) / sizeof(sndout_avail[0]); i++) {
+		if (sndout_avail[i].init() == 0)
+			break;
+	}
+
+	memcpy(&sndout_current, &sndout_avail[i], sizeof(sndout_current));
+	printf("using %s audio output driver\n", sndout_current.name);
+}