[SDL] Come riprodurre file Wave?

[DanieleC88]

Come posso riprodurre un file Wave usando SDL? Sto usando questo codice:

Dichiarazione:

SDL_AudioSpec			sdl_desired			=	{
		22050,				/* frequency */
		AUDIO_S16,		/* format */
		0,						/* channels */
		0,						/*	not used (computed by SDL) */
		1024,					/* samples */
		0,						/*	not used (computed by SDL) */
		0,						/*	not used (computed by SDL) */
		mix_sound,		/* callback function */
		NULL					/*	not used (user data that we don't need) */
	};

SDL_AudioSpec			wav_audiospec;
unsigned char *		wav_buffer			=	NULL;
unsigned int			wav_length			=	0;
unsigned int			wav_position		=	0;

Inizializzazione:

	if (!SDL_OpenAudio(&sdl_desired, NULL))
	{
		fprintf(stderr, "Cannot open audio device (\"%s\").\n", SDL_GetError());
		exit(ERROR);
	}
	else
	{
		if (!SDL_LoadWAV("data/background.wav", &wav_audiospec, &wav_buffer, &wav_length))
		{
			fprintf(stderr, "Cannot open audio file (\"%s\").\n", SDL_GetError());
			exit(ERROR);
		}
		else
		{
			SDL_PauseAudio(FALSE);
		}
	}

Funzione di mixaggio:

void	mix_sound(void * data, unsigned char * stream, int len)
{
	SDL_MixAudio(stream, (wav_buffer+wav_position), len, SDL_MIX_MAXVOLUME);
	wav_position	+= len;
	wav_length		-= len;
	return;
}

Quando eseguo il codice non sento alcun suono. Dove sbaglio?