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path: root/3rdparty/ymfm/examples/vgmrender/vgmrender.cpp
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//
// Simple vgm renderer.
//
// Leverages em_inflate tiny inflater from https://github.com/emmanuel-marty/em_inflate
//
// Compile with:
//
//   g++ --std=c++14 -I../../src vgmrender.cpp em_inflate.cpp ../../src/ymfm_misc.cpp ../../src/ymfm_opl.cpp ../../src/ymfm_opm.cpp ../../src/ymfm_opn.cpp ../../src/ymfm_adpcm.cpp ../../src/ymfm_pcm.cpp ../../src/ymfm_ssg.cpp -o vgmrender.exe
//
// or:
//
//   clang++ --std=c++14 -I../../src vgmrender.cpp em_inflate.cpp ../../src/ymfm_misc.cpp ../../src/ymfm_opl.cpp ../../src/ymfm_opm.cpp ../../src/ymfm_opn.cpp ../../src/ymfm_adpcm.cpp ../../src/ymfm_pcm.cpp ../../src/ymfm_ssg.cpp -o vgmrender.exe
//
// or:
//
//   cl -I..\..\src vgmrender.cpp em_inflate.cpp ..\..\src\ymfm_misc.cpp ..\..\src\ymfm_opl.cpp ..\..\src\ymfm_opm.cpp ..\..\src\ymfm_opn.cpp ..\..\src\ymfm_adpcm.cpp ..\..\src\ymfm_pcm.cpp ..\..\src\ymfm_ssg.cpp /Od /Zi /std:c++14 /EHsc
//

#define _CRT_SECURE_NO_WARNINGS

#include <cmath>
#include <cstdio>
#include <cstdint>
#include <cstring>
#include <list>
#include <string>

#include "em_inflate.h"
#include "ymfm_misc.h"
#include "ymfm_opl.h"
#include "ymfm_opm.h"
#include "ymfm_opn.h"

#define LOG_WRITES (0)

// run this many dummy clocks of each chip before generating
#define EXTRA_CLOCKS (0)


// enable this to run the nuked OPN2 core in parallel; output is not captured,
// but logging can be added to observe behaviors
#define RUN_NUKED_OPN2 (0)
#if (RUN_NUKED_OPN2)
namespace nuked {
bool s_log_envelopes = false;
const int s_log_envelopes_channel = 5;
#include "test/ym3438.h"
}
#endif

// enable this to capture each chip at its native rate as well
#define CAPTURE_NATIVE (0 || RUN_NUKED_OPN2)



//*********************************************************
//  GLOBAL TYPES
//*********************************************************

// we use an int64_t as emulated time, as a 32.32 fixed point value
using emulated_time = int64_t;

// enumeration of the different types of chips we support
enum chip_type
{
	CHIP_YM2149,
	CHIP_YM2151,
	CHIP_YM2203,
	CHIP_YM2413,
	CHIP_YM2608,
	CHIP_YM2610,
	CHIP_YM2612,
	CHIP_YM3526,
	CHIP_Y8950,
	CHIP_YM3812,
	CHIP_YMF262,
	CHIP_YMF278B,
	CHIP_TYPES
};



//*********************************************************
//  CLASSES
//*********************************************************

// ======================> vgm_chip_base

// abstract base class for a Yamaha chip; we keep a list of these for processing
// as new commands come in
class vgm_chip_base
{
public:
	// construction
	vgm_chip_base(uint32_t clock, chip_type type, char const *name) :
		m_type(type),
		m_name(name)
	{
	}

	// destruction
	virtual ~vgm_chip_base()
	{
	}

	// simple getters
	chip_type type() const { return m_type; }
	virtual uint32_t sample_rate() const = 0;

	// required methods for derived classes to implement
	virtual void write(uint32_t reg, uint8_t data) = 0;
	virtual void generate(emulated_time output_start, emulated_time output_step, int32_t *buffer) = 0;

	// write data to the ADPCM-A buffer
	void write_data(ymfm::access_class type, uint32_t base, uint32_t length, uint8_t const *src)
	{
		uint32_t end = base + length;
		if (end > m_data[type].size())
			m_data[type].resize(end);
		memcpy(&m_data[type][base], src, length);
	}

	// seek within the PCM stream
	void seek_pcm(uint32_t pos) { m_pcm_offset = pos; }
	uint8_t read_pcm() { auto &pcm = m_data[ymfm::ACCESS_PCM]; return (m_pcm_offset < pcm.size()) ? pcm[m_pcm_offset++] : 0; }

protected:
	// internal state
	chip_type m_type;
	std::string m_name;
	std::vector<uint8_t> m_data[ymfm::ACCESS_CLASSES];
	uint32_t m_pcm_offset;
#if (CAPTURE_NATIVE)
public:
	std::vector<int32_t> m_native_data;
#endif
#if (RUN_NUKED_OPN2)
public:
	nuked::ym3438_t *m_external = nullptr;
	std::vector<int32_t> m_nuked_data;
#endif
};


// ======================> vgm_chip

// actual chip-specific implementation class; includes implementatino of the
// ymfm_interface as needed for vgmplay purposes
template<typename ChipType>
class vgm_chip : public vgm_chip_base, public ymfm::ymfm_interface
{
public:
	// construction
	vgm_chip(uint32_t clock, chip_type type, char const *name) :
		vgm_chip_base(clock, type, name),
		m_chip(*this),
		m_clock(clock),
		m_clocks(0),
		m_step(0x100000000ull / m_chip.sample_rate(clock)),
		m_pos(0)
	{
		m_chip.reset();

		for (int clock = 0; clock < EXTRA_CLOCKS; clock++)
			m_chip.generate(&m_output);

#if (RUN_NUKED_OPN2)
		if (type == CHIP_YM2612)
		{
			m_external = new nuked::ym3438_t;
			nuked::OPN2_SetChipType(nuked::ym3438_mode_ym2612);
			nuked::OPN2_Reset(m_external);
			nuked::Bit16s buffer[2];
			for (int clocks = 0; clocks < 24 * EXTRA_CLOCKS; clocks++)
				nuked::OPN2_Clock(m_external, buffer);
		}
#endif
	}

	virtual uint32_t sample_rate() const override
	{
		return m_chip.sample_rate(m_clock);
	}

	// handle a register write: just queue for now
	virtual void write(uint32_t reg, uint8_t data) override
	{
		m_queue.push_back(std::make_pair(reg, data));
	}

	// generate one output sample of output
	virtual void generate(emulated_time output_start, emulated_time output_step, int32_t *buffer) override
	{
		uint32_t addr1 = 0xffff, addr2 = 0xffff;
		uint8_t data1 = 0, data2 = 0;

		// see if there is data to be written; if so, extract it and dequeue
		if (!m_queue.empty())
		{
			auto front = m_queue.front();
			addr1 = 0 + 2 * ((front.first >> 8) & 3);
			data1 = front.first & 0xff;
			addr2 = addr1 + ((m_type == CHIP_YM2149) ? 2 : 1);
			data2 = front.second;
			m_queue.erase(m_queue.begin());
		}

		// write to the chip
		if (addr1 != 0xffff)
		{
			if (LOG_WRITES)
				printf("%10.5f: %s %03X=%02X\n", double(output_start) / double(1LL << 32), m_name.c_str(), data1 + 0x100 * (addr1/2), data2);
			m_chip.write(addr1, data1);
			m_chip.write(addr2, data2);
		}

		// generate at the appropriate sample rate
//		nuked::s_log_envelopes = (output_start >= (22ll << 32) && output_start < (24ll << 32));
		for ( ; m_pos <= output_start; m_pos += m_step)
		{
			m_chip.generate(&m_output);

#if (CAPTURE_NATIVE)
			// if capturing native, append each generated sample
			m_native_data.push_back(m_output.data[0]);
			m_native_data.push_back(m_output.data[ChipType::OUTPUTS > 1 ? 1 : 0]);
#endif

#if (RUN_NUKED_OPN2)
			// if running nuked, capture its output as well
			if (m_external != nullptr)
			{
				int32_t sum[2] = { 0 };
				if (addr1 != 0xffff)
					nuked::OPN2_Write(m_external, addr1, data1);
				nuked::Bit16s buffer[2];
				for (int clocks = 0; clocks < 12; clocks++)
				{
					nuked::OPN2_Clock(m_external, buffer);
					sum[0] += buffer[0];
					sum[1] += buffer[1];
				}
				if (addr2 != 0xffff)
					nuked::OPN2_Write(m_external, addr2, data2);
				for (int clocks = 0; clocks < 12; clocks++)
				{
					nuked::OPN2_Clock(m_external, buffer);
					sum[0] += buffer[0];
					sum[1] += buffer[1];
				}
				addr1 = addr2 = 0xffff;
				m_nuked_data.push_back(sum[0] / 24);
				m_nuked_data.push_back(sum[1] / 24);
			}
#endif
		}

		// add the final result to the buffer
		if (m_type == CHIP_YM2203)
		{
			int32_t out0 = m_output.data[0];
			int32_t out1 = m_output.data[1 % ChipType::OUTPUTS];
			int32_t out2 = m_output.data[2 % ChipType::OUTPUTS];
			int32_t out3 = m_output.data[3 % ChipType::OUTPUTS];
			*buffer++ += out0 + out1 + out2 + out3;
			*buffer++ += out0 + out1 + out2 + out3;
		}
		else if (m_type == CHIP_YM2608 || m_type == CHIP_YM2610)
		{
			int32_t out0 = m_output.data[0];
			int32_t out1 = m_output.data[1 % ChipType::OUTPUTS];
			int32_t out2 = m_output.data[2 % ChipType::OUTPUTS];
			*buffer++ += out0 + out2;
			*buffer++ += out1 + out2;
		}
		else if (m_type == CHIP_YMF278B)
		{
			*buffer++ += m_output.data[4 % ChipType::OUTPUTS];
			*buffer++ += m_output.data[5 % ChipType::OUTPUTS];
		}
		else if (ChipType::OUTPUTS == 1)
		{
			*buffer++ += m_output.data[0];
			*buffer++ += m_output.data[0];
		}
		else
		{
			*buffer++ += m_output.data[0];
			*buffer++ += m_output.data[1 % ChipType::OUTPUTS];
		}
		m_clocks++;
	}

protected:
	// handle a read from the buffer
	virtual uint8_t ymfm_external_read(ymfm::access_class type, uint32_t offset) override
	{
		auto &data = m_data[type];
		return (offset < data.size()) ? data[offset] : 0;
	}

	// internal state
	ChipType m_chip;
	uint32_t m_clock;
	uint64_t m_clocks;
	typename ChipType::output_data m_output;
	emulated_time m_step;
	emulated_time m_pos;
	std::vector<std::pair<uint32_t, uint8_t>> m_queue;
};



//*********************************************************
//  GLOBAL HELPERS
//*********************************************************

// global list of active chips
std::vector<std::unique_ptr<vgm_chip_base>> active_chips;


//-------------------------------------------------
//  parse_uint32 - parse a little-endian uint32_t
//-------------------------------------------------

uint32_t parse_uint32(std::vector<uint8_t> &buffer, uint32_t &offset)
{
	uint32_t result = buffer[offset++];
	result |= buffer[offset++] << 8;
	result |= buffer[offset++] << 16;
	result |= buffer[offset++] << 24;
	return result;
}


//-------------------------------------------------
//  add_chips - add 1 or 2 instances of the given
//  supported chip type
//-------------------------------------------------

template<typename ChipType>
void add_chips(uint32_t clock, chip_type type, char const *chipname)
{
	uint32_t clockval = clock & 0x3fffffff;
	int numchips = (clock & 0x40000000) ? 2 : 1;
	printf("Adding %s%s @ %dHz\n", (numchips == 2) ? "2 x " : "", chipname, clockval);
	for (int index = 0; index < numchips; index++)
	{
		char name[100];
		sprintf(name, "%s #%d", chipname, index);
		active_chips.push_back(std::make_unique<vgm_chip<ChipType>>(clockval, type, (numchips == 2) ? name : chipname));
	}

	if (type == CHIP_YM2608)
	{
		FILE *rom = fopen("ym2608_adpcm_rom.bin", "rb");
		if (rom == nullptr)
			fprintf(stderr, "Warning: YM2608 enabled but ym2608_adpcm_rom.bin not found\n");
		else
		{
			fseek(rom, 0, SEEK_END);
			uint32_t size = ftell(rom);
			fseek(rom, 0, SEEK_SET);
			std::vector<uint8_t> temp(size);
			fread(&temp[0], 1, size, rom);
			fclose(rom);
			for (auto &chip : active_chips)
				if (chip->type() == type)
					chip->write_data(ymfm::ACCESS_ADPCM_A, 0, size, &temp[0]);
		}
	}
}


//-------------------------------------------------
//  parse_header - parse the vgm header, adding
//  chips for anything we encounter that we can
//  support
//-------------------------------------------------

uint32_t parse_header(std::vector<uint8_t> &buffer)
{
	// +00: already checked the ID
	uint32_t offset = 4;

	// +04: parse the size
	uint32_t size = parse_uint32(buffer, offset);
	if (offset - 4 + size > buffer.size())
	{
		fprintf(stderr, "Total size for file is too small; file may be truncated\n");
		size = buffer.size() - 4;
	}
	buffer.resize(size + 4);

	// +08: parse the version
	uint32_t version = parse_uint32(buffer, offset);
	if (version > 0x171)
		fprintf(stderr, "Warning: version > 1.71 detected, some things may not work\n");

	// +0C: SN76489 clock
	uint32_t clock = parse_uint32(buffer, offset);
	if (clock != 0)
		fprintf(stderr, "Warning: clock for SN76489 specified (%d), but not supported\n", clock);

	// +10: YM2413 clock
	clock = parse_uint32(buffer, offset);
	if (clock != 0)
		add_chips<ymfm::ym2413>(clock, CHIP_YM2413, "YM2413");

	// +14: GD3 offset
	uint32_t dummy = parse_uint32(buffer, offset);

	// +18: Total # samples
	dummy = parse_uint32(buffer, offset);

	// +1C: Loop offset
	dummy = parse_uint32(buffer, offset);

	// +20: Loop # samples
	dummy = parse_uint32(buffer, offset);

	// +24: Rate
	dummy = parse_uint32(buffer, offset);

	// +28: SN76489 feedback / SN76489 shift register width / SN76489 Flags
	dummy = parse_uint32(buffer, offset);

	// +2C: YM2612 clock
	clock = parse_uint32(buffer, offset);
	if (version >= 0x110 && clock != 0)
		add_chips<ymfm::ym2612>(clock, CHIP_YM2612, "YM2612");

	// +30: YM2151 clock
	clock = parse_uint32(buffer, offset);
	if (version >= 0x110 && clock != 0)
		add_chips<ymfm::ym2151>(clock, CHIP_YM2151, "YM2151");

	// +34: VGM data offset
	uint32_t data_start = parse_uint32(buffer, offset);
	data_start += offset - 4;
	if (version < 0x150)
		data_start = 0x40;

	// +38: Sega PCM clock
	clock = parse_uint32(buffer, offset);
	if (version >= 0x151 && clock != 0)
		fprintf(stderr, "Warning: clock for Sega PCM specified, but not supported\n");

	// +3C: Sega PCM interface register
	dummy = parse_uint32(buffer, offset);

	// +40: RF5C68 clock
	if (offset + 4 > data_start)
		return data_start;
	clock = parse_uint32(buffer, offset);
	if (version >= 0x151 && clock != 0)
		fprintf(stderr, "Warning: clock for RF5C68 specified, but not supported\n");

	// +44: YM2203 clock
	if (offset + 4 > data_start)
		return data_start;
	clock = parse_uint32(buffer, offset);
	if (version >= 0x151 && clock != 0)
		add_chips<ymfm::ym2203>(clock, CHIP_YM2203, "YM2203");

	// +48: YM2608 clock
	if (offset + 4 > data_start)
		return data_start;
	clock = parse_uint32(buffer, offset);
	if (version >= 0x151 && clock != 0)
		add_chips<ymfm::ym2608>(clock, CHIP_YM2608, "YM2608");

	// +4C: YM2610/2610B clock
	if (offset + 4 > data_start)
		return data_start;
	clock = parse_uint32(buffer, offset);
	if (version >= 0x151 && clock != 0)
	{
		if (clock & 0x80000000)
			add_chips<ymfm::ym2610b>(clock, CHIP_YM2610, "YM2610B");
		else
			add_chips<ymfm::ym2610>(clock, CHIP_YM2610, "YM2610");
	}

	// +50: YM3812 clock
	if (offset + 4 > data_start)
		return data_start;
	clock = parse_uint32(buffer, offset);
	if (version >= 0x151 && clock != 0)
		add_chips<ymfm::ym3812>(clock, CHIP_YM3812, "YM3812");

	// +54: YM3526 clock
	if (offset + 4 > data_start)
		return data_start;
	clock = parse_uint32(buffer, offset);
	if (version >= 0x151 && clock != 0)
		add_chips<ymfm::ym3526>(clock, CHIP_YM3526, "YM3526");

	// +58: Y8950 clock
	if (offset + 4 > data_start)
		return data_start;
	clock = parse_uint32(buffer, offset);
	if (version >= 0x151 && clock != 0)
		add_chips<ymfm::y8950>(clock, CHIP_Y8950, "Y8950");

	// +5C: YMF262 clock
	if (offset + 4 > data_start)
		return data_start;
	clock = parse_uint32(buffer, offset);
	if (version >= 0x151 && clock != 0)
		add_chips<ymfm::ymf262>(clock, CHIP_YMF262, "YMF262");

	// +60: YMF278B clock
	if (offset + 4 > data_start)
		return data_start;
	clock = parse_uint32(buffer, offset);
	if (version >= 0x151 && clock != 0)
		add_chips<ymfm::ymf278b>(clock, CHIP_YMF278B, "YMF278B");

	// +64: YMF271 clock
	if (offset + 4 > data_start)
		return data_start;
	clock = parse_uint32(buffer, offset);
	if (version >= 0x151 && clock != 0)
		fprintf(stderr, "Warning: clock for YMF271 specified, but not supported\n");

	// +68: YMF280B clock
	if (offset + 4 > data_start)
		return data_start;
	clock = parse_uint32(buffer, offset);
	if (version >= 0x151 && clock != 0)
		fprintf(stderr, "Warning: clock for YMF280B specified, but not supported\n");

	// +6C: RF5C164 clock
	if (offset + 4 > data_start)
		return data_start;
	clock = parse_uint32(buffer, offset);
	if (version >= 0x151 && clock != 0)
		fprintf(stderr, "Warning: clock for RF5C164 specified, but not supported\n");

	// +70: PWM clock
	if (offset + 4 > data_start)
		return data_start;
	clock = parse_uint32(buffer, offset);
	if (version >= 0x151 && clock != 0)
		fprintf(stderr, "Warning: clock for PWM specified, but not supported\n");

	// +74: AY8910 clock
	if (offset + 4 > data_start)
		return data_start;
	clock = parse_uint32(buffer, offset);
	if (version >= 0x151 && clock != 0)
	{
		fprintf(stderr, "Warning: clock for AY8910 specified, substituting YM2149\n");
		add_chips<ymfm::ym2149>(clock, CHIP_YM2149, "YM2149");
	}

	// +78: AY8910 flags
	if (offset + 4 > data_start)
		return data_start;
	dummy = parse_uint32(buffer, offset);

	// +7C: volume / loop info
	if (offset + 4 > data_start)
		return data_start;
	dummy = parse_uint32(buffer, offset);
	if ((dummy & 0xff) != 0)
		printf("Volume modifier: %02X (=%d)\n", dummy & 0xff, int(pow(2, double(dummy & 0xff) / 0x20)));

	// +80: GameBoy DMG clock
	if (offset + 4 > data_start)
		return data_start;
	clock = parse_uint32(buffer, offset);
	if (version >= 0x161 && clock != 0)
		fprintf(stderr, "Warning: clock for GameBoy DMG specified, but not supported\n");

	// +84: NES APU clock
	if (offset + 4 > data_start)
		return data_start;
	clock = parse_uint32(buffer, offset);
	if (version >= 0x161 && clock != 0)
		fprintf(stderr, "Warning: clock for NES APU specified, but not supported\n");

	// +88: MultiPCM clock
	if (offset + 4 > data_start)
		return data_start;
	clock = parse_uint32(buffer, offset);
	if (version >= 0x161 && clock != 0)
		fprintf(stderr, "Warning: clock for MultiPCM specified, but not supported\n");

	// +8C: uPD7759 clock
	if (offset + 4 > data_start)
		return data_start;
	clock = parse_uint32(buffer, offset);
	if (version >= 0x161 && clock != 0)
		fprintf(stderr, "Warning: clock for uPD7759 specified, but not supported\n");

	// +90: OKIM6258 clock
	if (offset + 4 > data_start)
		return data_start;
	clock = parse_uint32(buffer, offset);
	if (version >= 0x161 && clock != 0)
		fprintf(stderr, "Warning: clock for OKIM6258 specified, but not supported\n");

	// +94: OKIM6258 Flags / K054539 Flags / C140 Chip Type / reserved
	if (offset + 4 > data_start)
		return data_start;
	dummy = parse_uint32(buffer, offset);

	// +98: OKIM6295 clock
	if (offset + 4 > data_start)
		return data_start;
	clock = parse_uint32(buffer, offset);
	if (version >= 0x161 && clock != 0)
		fprintf(stderr, "Warning: clock for OKIM6295 specified, but not supported\n");

	// +9C: K051649 clock
	if (offset + 4 > data_start)
		return data_start;
	clock = parse_uint32(buffer, offset);
	if (version >= 0x161 && clock != 0)
		fprintf(stderr, "Warning: clock for K051649 specified, but not supported\n");

	// +A0: K054539 clock
	if (offset + 4 > data_start)
		return data_start;
	clock = parse_uint32(buffer, offset);
	if (version >= 0x161 && clock != 0)
		fprintf(stderr, "Warning: clock for K054539 specified, but not supported\n");

	// +A4: HuC6280 clock
	if (offset + 4 > data_start)
		return data_start;
	clock = parse_uint32(buffer, offset);
	if (version >= 0x161 && clock != 0)
		fprintf(stderr, "Warning: clock for HuC6280 specified, but not supported\n");

	// +A8: C140 clock
	if (offset + 4 > data_start)
		return data_start;
	clock = parse_uint32(buffer, offset);
	if (version >= 0x161 && clock != 0)
		fprintf(stderr, "Warning: clock for C140 specified, but not supported\n");

	// +AC: K053260 clock
	if (offset + 4 > data_start)
		return data_start;
	clock = parse_uint32(buffer, offset);
	if (version >= 0x161 && clock != 0)
		fprintf(stderr, "Warning: clock for K053260 specified, but not supported\n");

	// +B0: Pokey clock
	if (offset + 4 > data_start)
		return data_start;
	clock = parse_uint32(buffer, offset);
	if (version >= 0x161 && clock != 0)
		fprintf(stderr, "Warning: clock for Pokey specified, but not supported\n");

	// +B4: QSound clock
	if (offset + 4 > data_start)
		return data_start;
	clock = parse_uint32(buffer, offset);
	if (version >= 0x161 && clock != 0)
		fprintf(stderr, "Warning: clock for QSound specified, but not supported\n");

	// +B8: SCSP clock
	if (offset + 4 > data_start)
		return data_start;
	clock = parse_uint32(buffer, offset);
	if (version >= 0x171 && clock != 0)
		fprintf(stderr, "Warning: clock for SCSP specified, but not supported\n");

	// +BC: extra header offset
	if (offset + 4 > data_start)
		return data_start;
	uint32_t extra_header = parse_uint32(buffer, offset);

	// +C0: WonderSwan clock
	if (offset + 4 > data_start)
		return data_start;
	clock = parse_uint32(buffer, offset);
	if (version >= 0x171 && clock != 0)
		fprintf(stderr, "Warning: clock for WonderSwan specified, but not supported\n");

	// +C4: VSU clock
	if (offset + 4 > data_start)
		return data_start;
	clock = parse_uint32(buffer, offset);
	if (version >= 0x171 && clock != 0)
		fprintf(stderr, "Warning: clock for VSU specified, but not supported\n");

	// +C8: SAA1099 clock
	if (offset + 4 > data_start)
		return data_start;
	clock = parse_uint32(buffer, offset);
	if (version >= 0x171 && clock != 0)
		fprintf(stderr, "Warning: clock for SAA1099 specified, but not supported\n");

	// +CC: ES5503 clock
	if (offset + 4 > data_start)
		return data_start;
	clock = parse_uint32(buffer, offset);
	if (version >= 0x171 && clock != 0)
		fprintf(stderr, "Warning: clock for ES5503 specified, but not supported\n");

	// +D0: ES5505/ES5506 clock
	if (offset + 4 > data_start)
		return data_start;
	clock = parse_uint32(buffer, offset);
	if (version >= 0x171 && clock != 0)
		fprintf(stderr, "Warning: clock for ES5505/ES5506 specified, but not supported\n");

	// +D4: ES5503 output channels / ES5505/ES5506 amount of output channels / C352 clock divider
	if (offset + 4 > data_start)
		return data_start;
	dummy = parse_uint32(buffer, offset);

	// +D8: X1-010 clock
	if (offset + 4 > data_start)
		return data_start;
	clock = parse_uint32(buffer, offset);
	if (version >= 0x171 && clock != 0)
		fprintf(stderr, "Warning: clock for X1-010 specified, but not supported\n");

	// +DC: C352 clock
	if (offset + 4 > data_start)
		return data_start;
	clock = parse_uint32(buffer, offset);
	if (version >= 0x171 && clock != 0)
		fprintf(stderr, "Warning: clock for C352 specified, but not supported\n");

	// +E0: GA20 clock
	if (offset + 4 > data_start)
		return data_start;
	clock = parse_uint32(buffer, offset);
	if (version >= 0x171 && clock != 0)
		fprintf(stderr, "Warning: clock for GA20 specified, but not supported\n");

	return data_start;
}


//-------------------------------------------------
//  find_chip - find the given chip and index
//-------------------------------------------------

vgm_chip_base *find_chip(chip_type type, uint8_t index)
{
	for (auto &chip : active_chips)
		if (chip->type() == type && index-- == 0)
			return chip.get();
	return nullptr;
}


//-------------------------------------------------
//  write_chip - handle a write to the given chip
//  and index
//-------------------------------------------------

void write_chip(chip_type type, uint8_t index, uint32_t reg, uint8_t data)
{
	vgm_chip_base *chip = find_chip(type, index);
	if (chip != nullptr)
		chip->write(reg, data);
}


//-------------------------------------------------
//  add_rom_data - add data to the given chip
//  type in the given access class
//-------------------------------------------------

void add_rom_data(chip_type type, ymfm::access_class access, std::vector<uint8_t> &buffer, uint32_t &localoffset, uint32_t size)
{
	uint32_t length = parse_uint32(buffer, localoffset);
	uint32_t start = parse_uint32(buffer, localoffset);
	for (int index = 0; index < 2; index++)
	{
		vgm_chip_base *chip = find_chip(type, index);
		if (chip != nullptr)
			chip->write_data(access, start, size, &buffer[localoffset]);
	}
}


//-------------------------------------------------
//  generate_all - generate everything described
//  in the vgmplay file
//-------------------------------------------------

void generate_all(std::vector<uint8_t> &buffer, uint32_t data_start, uint32_t output_rate, std::vector<int32_t> &wav_buffer)
{
	// set the offset to the data start and go
	uint32_t offset = data_start;
	bool done = false;
	emulated_time output_step = 0x100000000ull / output_rate;
	emulated_time output_pos = 0;
	while (!done && offset < buffer.size())
	{
		int delay = 0;
		uint8_t cmd = buffer[offset++];
		switch (cmd)
		{
			// YM2413, write value dd to register aa
			case 0x51:
			case 0xa1:
				write_chip(CHIP_YM2413, cmd >> 7, buffer[offset], buffer[offset + 1]);
				offset += 2;
				break;

			// YM2612 port 0, write value dd to register aa
			case 0x52:
			case 0xa2:
				write_chip(CHIP_YM2612, cmd >> 7, buffer[offset], buffer[offset + 1]);
				offset += 2;
				break;

			// YM2612 port 1, write value dd to register aa
			case 0x53:
			case 0xa3:
				write_chip(CHIP_YM2612, cmd >> 7, buffer[offset] | 0x100, buffer[offset + 1]);
				offset += 2;
				break;

			// YM2151, write value dd to register aa
			case 0x54:
			case 0xa4:
				write_chip(CHIP_YM2151, cmd >> 7, buffer[offset], buffer[offset + 1]);
				offset += 2;
				break;

			// YM2203, write value dd to register aa
			case 0x55:
			case 0xa5:
				write_chip(CHIP_YM2203, cmd >> 7, buffer[offset], buffer[offset + 1]);
				offset += 2;
				break;

			// YM2608 port 0, write value dd to register aa
			case 0x56:
			case 0xa6:
				write_chip(CHIP_YM2608, cmd >> 7, buffer[offset], buffer[offset + 1]);
				offset += 2;
				break;

			// YM2608 port 1, write value dd to register aa
			case 0x57:
			case 0xa7:
				write_chip(CHIP_YM2608, cmd >> 7, buffer[offset] | 0x100, buffer[offset + 1]);
				offset += 2;
				break;

			// YM2610 port 0, write value dd to register aa
			case 0x58:
			case 0xa8:
				write_chip(CHIP_YM2610, cmd >> 7, buffer[offset], buffer[offset + 1]);
				offset += 2;
				break;

			// YM2610 port 1, write value dd to register aa
			case 0x59:
			case 0xa9:
				write_chip(CHIP_YM2610, cmd >> 7, buffer[offset] | 0x100, buffer[offset + 1]);
				offset += 2;
				break;

			// YM3812, write value dd to register aa
			case 0x5a:
			case 0xaa:
				write_chip(CHIP_YM3812, cmd >> 7, buffer[offset], buffer[offset + 1]);
				offset += 2;
				break;

			// YM3526, write value dd to register aa
			case 0x5b:
			case 0xab:
				write_chip(CHIP_YM3526, cmd >> 7, buffer[offset], buffer[offset + 1]);
				offset += 2;
				break;

			// Y8950, write value dd to register aa
			case 0x5c:
			case 0xac:
				write_chip(CHIP_Y8950, cmd >> 7, buffer[offset], buffer[offset + 1]);
				offset += 2;
				break;

			// YMF262 port 0, write value dd to register aa
			case 0x5e:
			case 0xae:
				write_chip(CHIP_YMF262, cmd >> 7, buffer[offset], buffer[offset + 1]);
				offset += 2;
				break;

			// YMF262 port 1, write value dd to register aa
			case 0x5f:
			case 0xaf:
				write_chip(CHIP_YMF262, cmd >> 7, buffer[offset] | 0x100, buffer[offset + 1]);
				offset += 2;
				break;

			// Wait n samples, n can range from 0 to 65535 (approx 1.49 seconds)
			case 0x61:
				delay = buffer[offset] | (buffer[offset + 1] << 8);
				offset += 2;
				break;

			// wait 735 samples (60th of a second)
			case 0x62:
				delay = 735;
				break;

			// wait 882 samples (50th of a second)
			case 0x63:
				delay = 882;
				break;

			// end of sound data
			case 0x66:
				done = true;
				break;

			// data block
			case 0x67:
			{
				uint8_t dummy = buffer[offset++];
				if (dummy != 0x66)
					break;
				uint8_t type = buffer[offset++];
				uint32_t size = parse_uint32(buffer, offset);
				uint32_t localoffset = offset;

				switch (type)
				{
					case 0x01: // RF5C68 PCM data for use with associated commands
					case 0x02: // RF5C164 PCM data for use with associated commands
					case 0x03: // PWM PCM data for use with associated commands
					case 0x04: // OKIM6258 ADPCM data for use with associated commands
					case 0x05: // HuC6280 PCM data for use with associated commands
					case 0x06: // SCSP PCM data for use with associated commands
					case 0x07: // NES APU DPCM data for use with associated commands
						break;

					case 0x00: // YM2612 PCM data for use with associated commands
					{
						vgm_chip_base *chip = find_chip(CHIP_YM2612, 0);
						if (chip != nullptr)
							chip->write_data(ymfm::ACCESS_PCM, 0, size - 8, &buffer[localoffset]);
						break;
					}

					case 0x82: // YM2610 ADPCM ROM data
						add_rom_data(CHIP_YM2610, ymfm::ACCESS_ADPCM_A, buffer, localoffset, size - 8);
						break;

					case 0x81: // YM2608 DELTA-T ROM data
						add_rom_data(CHIP_YM2608, ymfm::ACCESS_ADPCM_B, buffer, localoffset, size - 8);
						break;

					case 0x83: // YM2610 DELTA-T ROM data
						add_rom_data(CHIP_YM2610, ymfm::ACCESS_ADPCM_B, buffer, localoffset, size - 8);
						break;

					case 0x84: // YMF278B ROM data
					case 0x87: // YMF278B RAM data
						add_rom_data(CHIP_YMF278B, ymfm::ACCESS_PCM, buffer, localoffset, size - 8);
						break;

					case 0x88: // Y8950 DELTA-T ROM data
						add_rom_data(CHIP_Y8950, ymfm::ACCESS_ADPCM_B, buffer, localoffset, size - 8);
						break;

					case 0x80: // Sega PCM ROM data
					case 0x85: // YMF271 ROM data
					case 0x86: // YMZ280B ROM data
					case 0x89: // MultiPCM ROM data
					case 0x8A: // uPD7759 ROM data
					case 0x8B: // OKIM6295 ROM data
					case 0x8C: // K054539 ROM data
					case 0x8D: // C140 ROM data
					case 0x8E: // K053260 ROM data
					case 0x8F: // Q-Sound ROM data
					case 0x90: // ES5505/ES5506 ROM data
					case 0x91: // X1-010 ROM data
					case 0x92: // C352 ROM data
					case 0x93: // GA20 ROM data
						break;

					case 0xC0: // RF5C68 RAM write
					case 0xC1: // RF5C164 RAM write
					case 0xC2: // NES APU RAM write
					case 0xE0: // SCSP RAM write
					case 0xE1: // ES5503 RAM write
						break;

					default:
						if (type >= 0x40 && type < 0x7f)
							printf("Compressed data block not supported\n");
						else
							printf("Unknown data block type 0x%02X\n", type);
						break;
				}
				offset += size;
				break;
			}

			// PCM RAM write
			case 0x68:
				printf("68: PCM RAM write\n");
				break;

			// AY8910, write value dd to register aa
			case 0xa0:
				write_chip(CHIP_YM2149, buffer[offset] >> 7, buffer[offset] & 0x7f, buffer[offset + 1]);
				offset += 2;
				break;

			// pp aa dd: YMF278B, port pp, write value dd to register aa
			case 0xd0:
				write_chip(CHIP_YMF278B, buffer[offset] >> 7, ((buffer[offset] & 0x7f) << 8) | buffer[offset + 1], buffer[offset + 2]);
				offset += 3;
				break;

			case 0x70:	case 0x71:	case 0x72:	case 0x73:	case 0x74:	case 0x75:	case 0x76:	case 0x77:
			case 0x78:	case 0x79:	case 0x7a:	case 0x7b:	case 0x7c:	case 0x7d:	case 0x7e:	case 0x7f:
				delay = (cmd & 15) + 1;
				break;

			case 0x80:	case 0x81:	case 0x82:	case 0x83:	case 0x84:	case 0x85:	case 0x86:	case 0x87:
			case 0x88:	case 0x89:	case 0x8a:	case 0x8b:	case 0x8c:	case 0x8d:	case 0x8e:	case 0x8f:
			{
				vgm_chip_base *chip = find_chip(CHIP_YM2612, 0);
				if (chip != nullptr)
					chip->write(0x2a, chip->read_pcm());
				delay = cmd & 15;
				break;
			}

			// ignored, consume one byte
			case 0x30:	case 0x31:	case 0x32:	case 0x33:	case 0x34:	case 0x35:	case 0x36:	case 0x37:
			case 0x38:	case 0x39:	case 0x3a:	case 0x3b:	case 0x3c:	case 0x3d:	case 0x3e:	case 0x3f:
			case 0x4f:	// dd: Game Gear PSG stereo, write dd to port 0x06
			case 0x50:	// dd: PSG (SN76489/SN76496) write value dd
				offset++;
				break;

			// ignored, consume two bytes
			case 0x40:	case 0x41:	case 0x42:	case 0x43:	case 0x44:	case 0x45:	case 0x46:	case 0x47:
			case 0x48:	case 0x49:	case 0x4a:	case 0x4b:	case 0x4c:	case 0x4d:	case 0x4e:
			case 0x5d:	// aa dd: YMZ280B, write value dd to register aa
			case 0xb0:	// aa dd: RF5C68, write value dd to register aa
			case 0xb1:	// aa dd: RF5C164, write value dd to register aa
			case 0xb2:	// aa dd: PWM, write value ddd to register a (d is MSB, dd is LSB)
			case 0xb3:	// aa dd: GameBoy DMG, write value dd to register aa
			case 0xb4:	// aa dd: NES APU, write value dd to register aa
			case 0xb5:	// aa dd: MultiPCM, write value dd to register aa
			case 0xb6:	// aa dd: uPD7759, write value dd to register aa
			case 0xb7:	// aa dd: OKIM6258, write value dd to register aa
			case 0xb8:	// aa dd: OKIM6295, write value dd to register aa
			case 0xb9:	// aa dd: HuC6280, write value dd to register aa
			case 0xba:	// aa dd: K053260, write value dd to register aa
			case 0xbb:	// aa dd: Pokey, write value dd to register aa
			case 0xbc:	// aa dd: WonderSwan, write value dd to register aa
			case 0xbd:	// aa dd: SAA1099, write value dd to register aa
			case 0xbe:	// aa dd: ES5506, write value dd to register aa
			case 0xbf:	// aa dd: GA20, write value dd to register aa
				offset += 2;
				break;

			// ignored, consume three bytes
			case 0xc9:	case 0xca:	case 0xcb:	case 0xcc:	case 0xcd:	case 0xce:	case 0xcf:
			case 0xd7:	case 0xd8:	case 0xd9: 	case 0xda:	case 0xdb:	case 0xdc:	case 0xdd:	case 0xde:	case 0xdf:
			case 0xc0:	// bbaa dd: Sega PCM, write value dd to memory offset aabb
			case 0xc1:	// bbaa dd: RF5C68, write value dd to memory offset aabb
			case 0xc2:	// bbaa dd: RF5C164, write value dd to memory offset aabb
			case 0xc3:	// cc bbaa: MultiPCM, write set bank offset aabb to channel cc
			case 0xc4:	// mmll rr: QSound, write value mmll to register rr (mm - data MSB, ll - data LSB)
			case 0xc5:	// mmll dd: SCSP, write value dd to memory offset mmll (mm - offset MSB, ll - offset LSB)
			case 0xc6:	// mmll dd: WonderSwan, write value dd to memory offset mmll (mm - offset MSB, ll - offset LSB)
			case 0xc7:	// mmll dd: VSU, write value dd to memory offset mmll (mm - offset MSB, ll - offset LSB)
			case 0xc8:	// mmll dd: X1-010, write value dd to memory offset mmll (mm - offset MSB, ll - offset LSB)
			case 0xd1:	// pp aa dd: YMF271, port pp, write value dd to register aa
			case 0xd2:	// pp aa dd: SCC1, port pp, write value dd to register aa
			case 0xd3:	// pp aa dd: K054539, write value dd to register ppaa
			case 0xd4:	// pp aa dd: C140, write value dd to register ppaa
			case 0xd5:	// pp aa dd: ES5503, write value dd to register ppaa
			case 0xd6:	// pp aa dd: ES5506, write value aadd to register pp
				offset += 3;
				break;

			// ignored, consume four bytes
			case 0xe0:	// dddddddd: Seek to offset dddddddd (Intel byte order) in PCM data bank of data block type 0 (YM2612).
			{
				vgm_chip_base *chip = find_chip(CHIP_YM2612, 0);
				uint32_t pos = parse_uint32(buffer, offset);
				if (chip != nullptr)
					chip->seek_pcm(pos);
				offset += 4;
				break;
			}
			case 0xe1:	// mmll aadd: C352, write value aadd to register mmll
			case 0xe2:	case 0xe3:	case 0xe4:	case 0xe5:	case 0xe6:	case 0xe7:
			case 0xe8:	case 0xe9:	case 0xea:	case 0xeb:	case 0xec:	case 0xed:	case 0xee:	case 0xef:
			case 0xf0:	case 0xf1:	case 0xf2:	case 0xf3:	case 0xf4:	case 0xf5:	case 0xf6:	case 0xf7:
			case 0xf8:	case 0xf9:	case 0xfa:	case 0xfb:	case 0xfc:	case 0xfd:	case 0xfe:	case 0xff:
				offset += 4;
				break;
		}

		// handle delays
		while (delay-- != 0)
		{
			bool more_remaining = false;
			int32_t outputs[2] = { 0 };
			for (auto &chip : active_chips)
				chip->generate(output_pos, output_step, outputs);
			output_pos += output_step;
			wav_buffer.push_back(outputs[0]);
			wav_buffer.push_back(outputs[1]);
		}
	}
}


//-------------------------------------------------
//  write_wav - write a WAV file from the provided
//  stereo data
//-------------------------------------------------

int write_wav(char const *filename, uint32_t output_rate, std::vector<int32_t> &wav_buffer_src)
{
	// determine normalization parameters
	int32_t max_scale = 0;
	for (size_t index = 0; index < wav_buffer_src.size(); index++)
	{
		int32_t absval = std::abs(wav_buffer_src[index]);
		max_scale = std::max(max_scale, absval);
	}

	// warn if only silence was detected (and also avoid divide by zero)
	if (max_scale == 0)
	{
		fprintf(stderr, "The WAV file data will only contain silence.\n");
		max_scale = 1;
	}

	// now convert
	std::vector<int16_t> wav_buffer(wav_buffer_src.size());
	for (size_t index = 0; index < wav_buffer_src.size(); index++)
		wav_buffer[index] = wav_buffer_src[index] * 26000 / max_scale;

	// write the WAV file
	FILE *out = fopen(filename, "wb");
	if (out == nullptr)
	{
		fprintf(stderr, "Error creating output file '%s'\n", filename);
		return 6;
	}

	// write the 'RIFF' header
	if (fwrite("RIFF", 1, 4, out) != 4)
	{
		fprintf(stderr, "Error writing to output file\n");
		return 7;
	}

	// write the total size
	uint32_t total_size = 48 + wav_buffer.size() * 2 - 8;
	uint8_t wavdata[4];
	wavdata[0] = total_size >> 0;
	wavdata[1] = total_size >> 8;
	wavdata[2] = total_size >> 16;
	wavdata[3] = total_size >> 24;
	if (fwrite(wavdata, 1, 4, out) != 4)
	{
		fprintf(stderr, "Error writing to output file\n");
		return 7;
	}

	// write the 'WAVE' type
	if (fwrite("WAVE", 1, 4, out) != 4)
	{
		fprintf(stderr, "Error writing to output file\n");
		return 7;
	}

	// write the 'fmt ' tag
	if (fwrite("fmt ", 1, 4, out) != 4)
	{
		fprintf(stderr, "Error writing to output file\n");
		return 7;
	}

	// write the format length
	wavdata[0] = 16;
	wavdata[1] = 0;
	wavdata[2] = 0;
	wavdata[3] = 0;
	if (fwrite(wavdata, 1, 4, out) != 4)
	{
		fprintf(stderr, "Error writing to output file\n");
		return 7;
	}

	// write the format (PCM)
	wavdata[0] = 1;
	wavdata[1] = 0;
	if (fwrite(wavdata, 1, 2, out) != 2)
	{
		fprintf(stderr, "Error writing to output file\n");
		return 7;
	}

	// write the channels
	wavdata[0] = 2;
	wavdata[1] = 0;
	if (fwrite(wavdata, 1, 2, out) != 2)
	{
		fprintf(stderr, "Error writing to output file\n");
		return 7;
	}

	// write the sample rate
	wavdata[0] = output_rate >> 0;
	wavdata[1] = output_rate >> 8;
	wavdata[2] = output_rate >> 16;
	wavdata[3] = output_rate >> 24;
	if (fwrite(wavdata, 1, 4, out) != 4)
	{
		fprintf(stderr, "Error writing to output file\n");
		return 7;
	}

	// write the bytes/second
	uint32_t bps = output_rate * 2 * 2;
	wavdata[0] = bps >> 0;
	wavdata[1] = bps >> 8;
	wavdata[2] = bps >> 16;
	wavdata[3] = bps >> 24;
	if (fwrite(wavdata, 1, 4, out) != 4)
	{
		fprintf(stderr, "Error writing to output file\n");
		return 7;
	}

	// write the block align
	wavdata[0] = 4;
	wavdata[1] = 0;
	if (fwrite(wavdata, 1, 2, out) != 2)
	{
		fprintf(stderr, "Error writing to output file\n");
		return 7;
	}

	// write the bits/sample
	wavdata[0] = 16;
	wavdata[1] = 0;
	if (fwrite(wavdata, 1, 2, out) != 2)
	{
		fprintf(stderr, "Error writing to output file\n");
		return 7;
	}

	// write the 'data' tag
	if (fwrite("data", 1, 4, out) != 4)
	{
		fprintf(stderr, "Error writing to output file\n");
		return 7;
	}

	// write the data length
	uint32_t datalen = wav_buffer.size() * 2;
	wavdata[0] = datalen >> 0;
	wavdata[1] = datalen >> 8;
	wavdata[2] = datalen >> 16;
	wavdata[3] = datalen >> 24;
	if (fwrite(wavdata, 1, 4, out) != 4)
	{
		fprintf(stderr, "Error writing to output file\n");
		return 7;
	}

	// write the data
	if (fwrite(&wav_buffer[0], 1, datalen, out) != datalen)
	{
		fprintf(stderr, "Error writing to output file\n");
		return 7;
	}
	fclose(out);
	return 0;
}


//-------------------------------------------------
//  main - program entry point
//-------------------------------------------------

int main(int argc, char *argv[])
{
	char const *filename = nullptr;
	char const *outfilename = nullptr;
	int output_rate = 44100;

	// parse command line
	bool argerr = false;
	for (int arg = 1; arg < argc; arg++)
	{
		char const *curarg = argv[arg];
		if (*curarg == '-')
		{
			if (strcmp(curarg, "-o") == 0 || strcmp(curarg, "--output") == 0)
				outfilename = argv[++arg];
			else if (strcmp(curarg, "-r") == 0 || strcmp(curarg, "--samplerate") == 0)
				output_rate = atoi(argv[++arg]);
			else
			{
				fprintf(stderr, "Unknown argument: %s\n", curarg);
				argerr = true;
			}
		}
		else
			filename = curarg;
	}

	// if invalid syntax, show usage
	if (argerr || filename == nullptr || outfilename == nullptr)
	{
		fprintf(stderr, "Usage: vgmrender <inputfile> -o <outputfile> [-r <rate>]\n");
		return 1;
	}

	// attempt to read the file
	FILE *file = fopen(filename, "rb");
	if (file == nullptr)
	{
		fprintf(stderr, "Error opening file '%s'\n", filename);
		return 2;
	}

	// get the length and create a buffer
	fseek(file, 0, SEEK_END);
	uint32_t size = ftell(file);
	fseek(file, 0, SEEK_SET);
	std::vector<uint8_t> buffer(size);

	// read the contents
	auto bytes_read = fread(&buffer[0], 1, size, file);
	if (bytes_read != size)
	{
		fprintf(stderr, "Error reading file contents\n");
		return 3;
	}
	fclose(file);

	// check for gzip-format
	if (buffer.size() >= 10 && buffer[0] == 0x1f && buffer[1] == 0x8b && buffer[2] == 0x08)
	{
		// copy the raw data to a new buffer
		std::vector<uint8_t> compressed = buffer;

		// determine uncompressed size and resize the buffer
		uint8_t *end = &compressed[compressed.size()];
		uint32_t uncompressed = end[-4] | (end[-3] << 8) | (end[-2] << 16) | (end[-1] << 24);
		if (size < compressed.size() || size > 32*1024*1024)
		{
			fprintf(stderr, "File '%s' appears to be a compressed file but has unexpected size of %d\n", filename, size);
			return 4;
		}
		buffer.resize(uncompressed);

		// decompress the data
		auto result = em_inflate(&compressed[0], compressed.size(), &buffer[0], buffer.size());
		if (result == -1)
		{
			fprintf(stderr, "Error decompressing data from file\n");
			return 4;
		}
	}

	// check the ID
	uint32_t offset = 0;
	if (buffer.size() < 64 || buffer[0] != 'V' || buffer[1] != 'g' || buffer[2] != 'm' || buffer[3] != ' ')
	{
		fprintf(stderr, "File '%s' does not appear to be a valid VGM file\n", filename);
		return 4;
	}

	// parse the header, creating any chips needed
	uint32_t data_start = parse_header(buffer);

	// if no chips created, fail
	if (active_chips.size() == 0)
	{
		fprintf(stderr, "No compatible chips found, exiting.\n");
		return 5;
	}

	// generate the output
	std::vector<int32_t> wav_buffer;
	generate_all(buffer, data_start, output_rate, wav_buffer);

	int err = write_wav(outfilename, output_rate, wav_buffer);

#if (CAPTURE_NATIVE)
	{
		int chipnum = 0;
		for (auto &chip : active_chips)
			if (err == 0 && chip->m_native_data.size() > 0)
			{
				char filename[20];
				sprintf(filename, "native-%d.wav", chipnum++);
				err = write_wav(filename, chip->sample_rate(), chip->m_native_data);
			}
	}
#endif
#if (RUN_NUKED_OPN2)
	{
		int chipnum = 0;
		for (auto &chip : active_chips)
			if (err == 0 && chip->m_nuked_data.size() > 0)
			{
				char filename[20];
				sprintf(filename, "nuked-%d.wav", chipnum++);
				err = write_wav(filename, chip->sample_rate(), chip->m_nuked_data);
			}
	}
#endif

	active_chips.clear();

	return err;
}

#if (RUN_NUKED_OPN2)
namespace nuked {
#include "test/ym3438.c"
}
#endif