Start work on using OpenSL conditionally (to still support Android 2.2)

android/native_audio.cpp

@@ -0,0 +1,34 @@
+#include <dlfcn.h>
+
+#include "base/logging.h"
+#include "android/native_audio.h"
+#include "android/native-audio-so.h"
+
+static void *so;
+static OpenSLWrap_Init_T init_func;
+static OpenSLWrap_Shutdown_T shutdown_func;
+
+bool AndroidAudio_Init(AndroidAudioCallback cb) {
+	ILOG("Loading native audio library...");
+	so = dlopen("libnative_audio.so", RTLD_NOW);
+	if (!so) {
+		ELOG("Failed to find native audio library");
+		return false;
+	}
+	init_func = (OpenSLWrap_Init_T)dlsym(so, "OpenSLWrap_Init");
+	shutdown_func = (OpenSLWrap_Shutdown_T)dlsym(so, "OpenSLWrap_Shutdown");
+
+	ILOG("Calling OpenSLWrap_Init_T...");
+	bool init_retval = init_func(cb);
+	ILOG("Returned from OpenSLWrap_Init_T");
+	return init_retval;
+}
+
+
+void AndroidAudio_Shutdown() {
+	ILOG("Calling OpenSLWrap_Shutdown_T...");
+	shutdown_func();
+	ILOG("Returned from OpenSLWrap_Shutdown_T");
+	dlclose(so);
+	so = 0;
+}