Function parse

src/resource/sound_ogg.cpp:37–147

namespace ogg
{
	s32 parse(Sound &s, Buffer &buf, CompileOptions &opts)
	{
		OggStreamMetadata ogg;
		const u8 *data = (u8 *)array::begin(buf);
		const u32 size = array::size(buf);
		int p = 0;
		int q = 1;

		int used;
		int error;
		stb_vorbis *v;
		while (true) {
			v = stb_vorbis_open_pushdata(data, q, &used, &error, NULL);
			if (v != NULL)
				break;

			RETURN_IF_FALSE(OGG, error == VORBIS_need_more_data
				, opts
				, "stb_vorbis_open_pushdata: error: %d"
				, error
				);
			q += 1;
		}

		RETURN_IF_FALSE(OGG, v != NULL, opts, "stb_vorbis_open_pushdata: error: %d", error);
		p += used;
		ogg.headers_size = p;

		stb_vorbis_info info = stb_vorbis_get_info(v);
		ogg.alloc_buffer_size = info.setup_memory_required
			+ info.setup_temp_memory_required
			+ info.temp_memory_required
			;
		ogg.max_frame_size = info.max_frame_size;

		// Decode SOUND_PCM_MS worth of audio samples.
		unsigned int wanted_n = info.sample_rate / 1000 * SOUND_PCM_MS;
		ogg.num_samples_skip = wanted_n;

		FileBuffer fb(buf);
		fb.seek(p);

		p = 0;
		unsigned int total_n = 0;
		unsigned char *mem = (unsigned char *)default_allocator().allocate(info.max_frame_size);

		// Decode up to wanted_n samples.
		while (total_n < wanted_n) {
			float **output;
			int n;
			q = info.max_frame_size;

		retry:
			if (q > (int)size - p)
				q = (int)size - p;
			if (p < q)
				fb.read(&mem[p], q - p);