86Box/src/cdrom/cdrom.c

/*
 * 86Box	A hypervisor and IBM PC system emulator that specializes in
 *		running old operating systems and software designed for IBM
 *		PC systems and compatibles from 1981 through fairly recent
 *		system designs based on the PCI bus.
 *
 *		This file is part of the 86Box distribution.
 *
 *		Generic CD-ROM drive core.
 *
 * Version:	@(#)cdrom.c	1.0.8	2019/09/26
 *
 * Author:	Miran Grca, <mgrca8@gmail.com>
 *
 *		Copyright 2018,2019 Miran Grca.
 */
#include <inttypes.h>
#include <stdarg.h>
#include <stdint.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <wchar.h>
#define HAVE_STDARG_H
#include "../86box.h"
#include "../config.h"
#include "cdrom.h"
#include "cdrom_image.h"
#include "../plat.h"
#include "../sound/sound.h"


/* The addresses sent from the guest are absolute, ie. a LBA of 0 corresponds to a MSF of 00:00:00. Otherwise, the counter displayed by the guest is wrong:
   there is a seeming 2 seconds in which audio plays but counter does not move, while a data track before audio jumps to 2 seconds before the actual start
   of the audio while audio still plays. With an absolute conversion, the counter is fine. */
#define MSFtoLBA(m,s,f)		((((m*60)+s)*75)+f)

#define RAW_SECTOR_SIZE		2352
#define COOKED_SECTOR_SIZE	2048

#define MIN_SEEK		2000
#define MAX_SEEK	      333333


#pragma pack(push,1)
typedef struct {
    uint8_t user_data[2048],
	    ecc[288];
} m1_data_t;

typedef struct {
    uint8_t sub_header[8],
    user_data[2328];
} m2_data_t;

typedef union {
    m1_data_t m1_data;
    m2_data_t m2_data;
    uint8_t raw_data[2336];
} sector_data_t;

typedef struct {
    uint8_t sync[12];
    uint8_t header[4];
    sector_data_t data;
} sector_raw_data_t;

typedef union {
    sector_raw_data_t sector_data;
    uint8_t raw_data[2352];
} sector_t;

typedef struct {
    sector_t sector;
    uint8_t c2[296];
    uint8_t subchannel_raw[96];
    uint8_t subchannel_q[16];
    uint8_t subchannel_rw[96];
} cdrom_sector_t;

typedef union {
    cdrom_sector_t cdrom_sector;
    uint8_t buffer[2856];
} sector_buffer_t;
#pragma pack(pop)


static int		cdrom_sector_size;
static uint8_t		raw_buffer[2856];	/* Needs to be the same size as sector_buffer_t in the structs. */
static uint8_t		extra_buffer[296];


cdrom_t	cdrom[CDROM_NUM];


#ifdef ENABLE_CDROM_LOG
int		cdrom_do_log = ENABLE_CDROM_LOG;


void
cdrom_log(const char *fmt, ...)
{
    va_list ap;

    if (cdrom_do_log) {
	va_start(ap, fmt);
	pclog_ex(fmt, ap);
	va_end(ap);
    }
}
#else
#define cdrom_log(fmt, ...)
#endif


int
cdrom_lba_to_msf_accurate(int lba)
{
    int pos;
    int m, s, f;

    pos = lba + 150;
    f = pos % 75;
    pos -= f;
    pos /= 75;
    s = pos % 60;
    pos -= s;
    pos /= 60;
    m = pos;

    return ((m << 16) | (s << 8) | f);
}


static double
cdrom_get_short_seek(cdrom_t *dev)
{
    switch(dev->cur_speed) {
	case 0:
		fatal("CD-ROM %i: 0x speed\n", dev->id);
		return 0.0;
	case 1:
		return 240.0;
	case 2:
		return 160.0;
	case 3:
		return 150.0;
	case 4: case 5: case 6: case 7: case 8:
	case 9: case 10: case 11:
		return 112.0;
	case 12: case 13: case 14: case 15:
		return 75.0;
	case 16: case 17: case 18: case 19:
		return 58.0;
	case 20: case 21: case 22: case 23:
	case 40: case 41: case 42: case 43:
	case 44: case 45: case 46: case 47:
	case 48:
		return 50.0;
	default:
		/* 24-32, 52+ */
		return 45.0;
    }
}


static double
cdrom_get_long_seek(cdrom_t *dev)
{
    switch(dev->cur_speed) {
	case 0:
		fatal("CD-ROM %i: 0x speed\n", dev->id);
		return 0.0;
	case 1:
		return 1446.0;
	case 2:
		return 1000.0;
	case 3:
		return 900.0;
	case 4: case 5: case 6: case 7: case 8:
	case 9: case 10: case 11:
		return 675.0;
	case 12: case 13: case 14: case 15:
		return 400.0;
	case 16: case 17: case 18: case 19:
		return 350.0;
	case 20: case 21: case 22: case 23:
	case 40: case 41: case 42: case 43:
	case 44: case 45: case 46: case 47:
	case 48:
		return 300.0;
	default:
		/* 24-32, 52+ */
	return 270.0;
    }
}


double
cdrom_seek_time(cdrom_t *dev)
{
    uint32_t diff = dev->seek_diff;
    double sd = (double) (MAX_SEEK - MIN_SEEK);

    if (diff < MIN_SEEK)
	return 0.0;
    if (diff > MAX_SEEK)
	diff = MAX_SEEK;

    diff -= MIN_SEEK;

    return cdrom_get_short_seek(dev) + ((cdrom_get_long_seek(dev) * ((double) diff)) / sd);
}


void
cdrom_stop(cdrom_t *dev)
{
    if (dev->cd_status > CD_STATUS_DATA_ONLY)
	dev->cd_status = CD_STATUS_STOPPED;
}


void
cdrom_seek(cdrom_t *dev, uint32_t pos)
{
    if (!dev)
	return;

    cdrom_log("CD-ROM %i: Seek to LBA %08X\n", dev->id, pos);

    dev->seek_pos   = pos;
    cdrom_stop(dev);
}


int
cdrom_audio_callback(cdrom_t *dev, int16_t *output, int len)
{
    int ret = 1;

    if (!dev->sound_on || (dev->cd_status != CD_STATUS_PLAYING)) {
	cdrom_log("CD-ROM %i: Audio callback while not playing\n", dev->id);
	if (dev->cd_status == CD_STATUS_PLAYING)
		dev->seek_pos += (len >> 11);
	memset(output, 0, len * 2);
	return 0;
    }

    while (dev->cd_buflen < len) {
	if (dev->seek_pos < dev->cd_end) {
		if (dev->ops->read_sector(dev, CD_READ_AUDIO,
					  (uint8_t *) &(dev->cd_buffer[dev->cd_buflen]),
					  dev->seek_pos)) {
			cdrom_log("CD-ROM %i: Read LBA %08X successful\n", dev->id, dev->seek_pos);
			dev->seek_pos++;
			dev->cd_buflen += (RAW_SECTOR_SIZE / 2);
			ret = 1;
		} else {
			cdrom_log("CD-ROM %i: Read LBA %08X failed\n", dev->id, dev->seek_pos);
			memset(&(dev->cd_buffer[dev->cd_buflen]),
			       0x00, (BUF_SIZE - dev->cd_buflen) * 2);
			dev->cd_status = CD_STATUS_STOPPED;
			dev->cd_buflen = len;
			ret = 0;
		}
	} else {
		cdrom_log("CD-ROM %i: Playing completed\n", dev->id);
		memset(&dev->cd_buffer[dev->cd_buflen],
		       0x00, (BUF_SIZE - dev->cd_buflen) * 2);
		dev->cd_status = CD_STATUS_PLAYING_COMPLETED;
		dev->cd_buflen = len;
		ret = 0;
	}
    }

    memcpy(output, dev->cd_buffer, len * 2);
    memmove(dev->cd_buffer, &dev->cd_buffer[len], (BUF_SIZE - len) * 2);
    dev->cd_buflen -= len;

    cdrom_log("CD-ROM %i: Audio callback returning %i\n", dev->id, ret);
    return ret;
}


uint8_t
cdrom_audio_play(cdrom_t *dev, uint32_t pos, uint32_t len, int ismsf)
{
    track_info_t ti;
    int m = 0, s = 0, f = 0;

    if (dev->cd_status == CD_STATUS_DATA_ONLY)
	return 0;

    cdrom_log("CD-ROM %i: Play audio - %08X %08X %i\n", dev->id, pos, len, ismsf);
    if (ismsf & 0x100) {
	/* Track-relative audio play. */
	dev->ops->get_track_info(dev, ismsf & 0xff, 0, &ti);
	pos += MSFtoLBA(ti.m, ti.s, ti.f) - 150;
    } else if (ismsf == 2) {
	dev->ops->get_track_info(dev, pos, 0, &ti);
	pos = MSFtoLBA(ti.m, ti.s, ti.f) - 150;
	/* We have to end at the *end* of the specified track,
	   not at the beginning. */
	dev->ops->get_track_info(dev, len, 1, &ti);
	len = MSFtoLBA(ti.m, ti.s, ti.f) - 150;
    } else if (ismsf == 1) {
	m = (pos >> 16) & 0xff;
	s = (pos >> 8) & 0xff;
	f = pos & 0xff;

	if (pos == 0xffffff) {
		cdrom_log("CD-ROM %i: Playing from current position (MSF)\n", dev->id);
		pos = dev->seek_pos;
	} else
		pos = MSFtoLBA(m, s, f) - 150;

	m = (len >> 16) & 0xff;
	s = (len >> 8) & 0xff;
	f = len & 0xff;
	len = MSFtoLBA(m, s, f) - 150;

	cdrom_log("CD-ROM %i: MSF - pos = %08X len = %08X\n", dev->id, pos, len);
    } else if (ismsf == 0) {
	if (pos == 0xffffffff) {
		cdrom_log("CD-ROM %i: Playing from current position\n", dev->id);
		pos = dev->seek_pos;
	}
	len += pos;
    }

    /* Do this at this point, since it's at this point that we know the
       actual LBA position to start playing from. */
    if (!(dev->ops->track_type(dev, pos) & CD_TRACK_AUDIO)) {
	pclog("CD-ROM %i: LBA %08X not on an audio track\n", dev->id, pos);
	cdrom_stop(dev);
	return 0;
    }

    dev->seek_pos = pos;
    dev->cd_end = len;
    dev->cd_status = CD_STATUS_PLAYING;
    dev->cd_buflen = 0;

    return 1;
}


void
cdrom_audio_pause_resume(cdrom_t *dev, uint8_t resume)
{
    if ((dev->cd_status == CD_STATUS_PLAYING) || (dev->cd_status == CD_STATUS_PAUSED))
	dev->cd_status = (dev->cd_status & 0xfe) | (resume & 0x01);
}


uint8_t
cdrom_get_current_subchannel(cdrom_t *dev, uint8_t *b, int msf)
{
    uint8_t ret;
    subchannel_t subc;
    int pos = 1;

    dev->ops->get_subchannel(dev, dev->seek_pos, &subc);
    cdrom_log("CD-ROM %i: Returned subchannel at %02i:%02i.%02i\n", subc.abs_m, subc.abs_s, subc.abs_f);

    if (dev->cd_status == CD_STATUS_DATA_ONLY)
	ret = 0x15;
    else {
	if (dev->cd_status == CD_STATUS_PLAYING)
		ret = 0x11;
	else if (dev->cd_status == CD_STATUS_PAUSED)
		ret = 0x12;
	else
		ret = 0x13;
    }

    if (b[pos] > 1)
	return ret;

    b[pos++] = subc.attr;
    b[pos++] = subc.track;
    b[pos++] = subc.index;

    if (msf) {
	b[pos]     = 0;
	b[pos + 1] = subc.abs_m;
	b[pos + 2] = subc.abs_s;
	b[pos + 3] = subc.abs_f;
	pos += 4;
	b[pos]     = 0;
	b[pos + 1] = subc.rel_m;
	b[pos + 2] = subc.rel_s;
	b[pos + 3] = subc.rel_f;
	pos += 4;
    } else {
	uint32_t dat = MSFtoLBA(subc.abs_m, subc.abs_s, subc.abs_f) - 150;
	b[pos++] = (dat >> 24) & 0xff;
	b[pos++] = (dat >> 16) & 0xff;
	b[pos++] = (dat >> 8) & 0xff;
	b[pos++] = dat & 0xff;
	dat = MSFtoLBA(subc.rel_m, subc.rel_s, subc.rel_f);
	b[pos++] = (dat >> 24) & 0xff;
	b[pos++] = (dat >> 16) & 0xff;
	b[pos++] = (dat >> 8) & 0xff;
	b[pos++] = dat & 0xff;
    }

    return ret;
}


static int
read_toc_normal(cdrom_t *dev, unsigned char *b, unsigned char start_track, int msf)
{
    track_info_t ti;
    int len = 4;
    int c, d, first_track, last_track;
    uint32_t temp;

    dev->ops->get_tracks(dev, &first_track, &last_track);

    b[2] = first_track;
    b[3] = last_track;

    d = 0;
    for (c = 0; c <= last_track; c++) {
	dev->ops->get_track_info(dev, c + 1, 0, &ti);
	if (ti.number >= start_track) {
		d = c;
		break;
	}
    }

    if (start_track != 0xAA) {
	dev->ops->get_track_info(dev, c + 1, 0, &ti);
	b[2] = ti.number;
    }

    for (c = d; c <= last_track; c++) {
	dev->ops->get_track_info(dev, c + 1, 0, &ti);

	b[len++] = 0; /* reserved */
	b[len++] = ti.attr;
	b[len++] = ti.number; /* track number */
	b[len++] = 0; /* reserved */

	if (msf) {
		b[len++] = 0;
		b[len++] = ti.m;
		b[len++] = ti.s;
		b[len++] = ti.f;
	} else {
		temp = MSFtoLBA(ti.m, ti.s, ti.f) - 150;
		b[len++] = temp >> 24;
		b[len++] = temp >> 16;
		b[len++] = temp >> 8;
		b[len++] = temp;
	}
    }

    return len;
}


static int
read_toc_session(cdrom_t *dev, unsigned char *b, int msf)
{
    track_info_t ti;
    int len = 4;
    uint32_t temp;

    dev->ops->get_track_info(dev, 1, 0, &ti);

    if (ti.number == 0)
	ti.number = 1;

    b[2] = b[3] = 1;
    b[len++] = 0; /* reserved */
    b[len++] = ti.attr;
    b[len++] = ti.number; /* track number */
    b[len++] = 0; /* reserved */
    if (msf) {
	b[len++] = 0;
	b[len++] = ti.m;
	b[len++] = ti.s;
	b[len++] = ti.f;
    } else {
	temp = MSFtoLBA(ti.m, ti.s, ti.f) - 150;	/* Do the - 150. */
	b[len++] = temp >> 24;
	b[len++] = temp >> 16;
	b[len++] = temp >> 8;
	b[len++] = temp;
    }

    return len;
}


static int
read_toc_raw(cdrom_t *dev, unsigned char *b)
{
    track_info_t ti;
    int first_track, last_track;
    int track, len = 4;

    dev->ops->get_tracks(dev, &first_track, &last_track);

    b[2] = first_track;
    b[3] = last_track;

    for (track = first_track; track <= last_track; track++) {
	dev->ops->get_track_info(dev, track, 0, &ti);

	b[len++] = track;
	b[len++] = ti.attr;
	b[len++] = 0;
	b[len++] = 0;
	b[len++] = 0;
	b[len++] = 0;
	b[len++] = 0;
	b[len++] = 0;
	b[len++] = ti.m;
	b[len++] = ti.s;
	b[len++] = ti.f;
    }

    return len;
}


int
cdrom_read_toc(cdrom_t *dev, unsigned char *b, int type, unsigned char start_track, int msf, int max_len)
{
    int len;

    switch(type) {
	case CD_TOC_NORMAL:
		len = read_toc_normal(dev, b, start_track, msf);
		break;
	case CD_TOC_SESSION:
		len = read_toc_session(dev, b, msf);
		break;
	case CD_TOC_RAW:
		len = read_toc_raw(dev, b);
		break;
	default:
		cdrom_log("CD-ROM %i: Unknown TOC read type: %i\n", dev->id, type);
		return 0;
    }

    len = MIN(len, max_len);

    b[0] = (uint8_t) (((len - 2) >> 8) & 0xff);
    b[1] = (uint8_t) ((len - 2) & 0xff);

    return len;
}


static int
track_type_is_valid(uint8_t id, int type, int flags, int audio, int mode2)
{
    if (!(flags & 0x70)) {		/* 0x00/0x08/0x80/0x88 are illegal modes */
	cdrom_log("CD-ROM %i: [Any Mode] 0x00/0x08/0x80/0x88 are illegal modes\n", id);
	return 0;
    }

    if ((type != 1) && !audio) {
	if (!(flags & 0x70)) {		/* 0x00/0x08/0x80/0x88 are illegal modes */
		cdrom_log("CD-ROM %i: [Any Data Mode] 0x00/0x08/0x80/0x88 are illegal modes\n", id);
		return 0;
	}

	if ((flags & 0x06) == 0x06) {
		cdrom_log("CD-ROM %i: [Any Data Mode] Invalid error flags\n", id);
		return 0;
	}

	if (((flags & 0x700) == 0x300) || ((flags & 0x700) > 0x400)) {
		cdrom_log("CD-ROM %i: [Any Data Mode] Invalid subchannel data flags (%02X)\n", id, flags & 0x700);
		return 0;
	}

	if ((flags & 0x18) == 0x08) {		/* EDC/ECC without user data is an illegal mode */
		cdrom_log("CD-ROM %i: [Any Data Mode] EDC/ECC without user data is an illegal mode\n", id);
		return 0;
	}

	if (((flags & 0xf0) == 0x90) || ((flags & 0xf0) == 0xc0)) {		/* 0x90/0x98/0xC0/0xC8 are illegal modes */
		cdrom_log("CD-ROM %i: [Any Data Mode] 0x90/0x98/0xC0/0xC8 are illegal modes\n", id);
		return 0;
	}

	if (((type > 3) && (type != 8)) || (mode2 && (mode2 & 0x03))) {
		if ((flags & 0xf0) == 0x30) {		/* 0x30/0x38 are illegal modes */
			cdrom_log("CD-ROM %i: [Any XA Mode 2] 0x30/0x38 are illegal modes\n", id);
			return 0;
		}
		if (((flags & 0xf0) == 0xb0) || ((flags & 0xf0) == 0xd0)) {	/* 0xBx and 0xDx are illegal modes */
			cdrom_log("CD-ROM %i: [Any XA Mode 2] 0xBx and 0xDx are illegal modes\n", id);
			return 0;
		}
	}
    }

    return 1;
}


static void
read_sector_to_buffer(cdrom_t *dev, uint8_t *rbuf, uint32_t msf, uint32_t lba, int mode2, int len)
{
    uint8_t *bb = rbuf;

    dev->ops->read_sector(dev, CD_READ_DATA, rbuf + 16, lba);

    /* Sync bytes */
    bb[0] = 0;
    memset(bb + 1, 0xff, 10);
    bb[11] = 0;
    bb += 12;

    /* Sector header */
    bb[0] = (msf >> 16) & 0xff;
    bb[1] = (msf >> 8) & 0xff;
    bb[2] = msf & 0xff;

    bb[3] = 1; /* mode 1 data */
    bb += mode2 ? 12 : 4;
    bb += len;
    if (mode2 && ((mode2 & 0x03) == 1))
	memset(bb, 0, 280);
    else if (!mode2)
	memset(bb, 0, 288);
}


static void
read_audio(cdrom_t *dev, uint32_t lba, uint8_t *b)
{
    dev->ops->read_sector(dev, CD_READ_RAW, raw_buffer, lba);

    memcpy(b, raw_buffer, 2352);

    cdrom_sector_size = 2352;
}


static void
read_mode1(cdrom_t *dev, int cdrom_sector_flags, uint32_t lba, uint32_t msf, int mode2, uint8_t *b)
{
    if ((dev->cd_status == CD_STATUS_DATA_ONLY) || (dev->ops->sector_size(dev, lba) == 2048))
	read_sector_to_buffer(dev, raw_buffer, msf, lba, mode2, 2048);
    else
	dev->ops->read_sector(dev, CD_READ_RAW, raw_buffer, lba);

    cdrom_sector_size = 0;

    if (cdrom_sector_flags & 0x80) {	/* Sync */
	cdrom_log("CD-ROM %i: [Mode 1] Sync\n", dev->id);
	memcpy(b, raw_buffer, 12);
	cdrom_sector_size += 12;
	b += 12;
    }

    if (cdrom_sector_flags & 0x20) {	/* Header */
	cdrom_log("CD-ROM %i: [Mode 1] Header\n", dev->id);
	memcpy(b, raw_buffer + 12, 4);
	cdrom_sector_size += 4;
	b += 4;
    }

    if (cdrom_sector_flags & 0x40) {	/* Sub-header */
	if (!(cdrom_sector_flags & 0x10)) {		/* No user data */
		cdrom_log("CD-ROM %i: [Mode 1] Sub-header\n", dev->id);
		memcpy(b, raw_buffer + 16, 8);
		cdrom_sector_size += 8;
		b += 8;
	}
    }

    if (cdrom_sector_flags & 0x10) {	/* User data */
	cdrom_log("CD-ROM %i: [Mode 1] User data\n", dev->id);
	memcpy(b, raw_buffer + 16, 2048);
	cdrom_sector_size += 2048;
	b += 2048;
    }

    if (cdrom_sector_flags & 0x08) {	/* EDC/ECC */
	cdrom_log("CD-ROM %i: [Mode 1] EDC/ECC\n", dev->id);
	memcpy(b, raw_buffer + 2064, 288);
	cdrom_sector_size += 288;
	b += 288;
    }
}


static void
read_mode2_non_xa(cdrom_t *dev, int cdrom_sector_flags, uint32_t lba, uint32_t msf, int mode2, uint8_t *b)
{
    if ((dev->cd_status == CD_STATUS_DATA_ONLY) || (dev->ops->sector_size(dev, lba) == 2336))
	read_sector_to_buffer(dev, raw_buffer, msf, lba, mode2, 2336);
    else
	dev->ops->read_sector(dev, CD_READ_RAW, raw_buffer, lba);

    cdrom_sector_size = 0;

    if (cdrom_sector_flags & 0x80) {	/* Sync */
	cdrom_log("CD-ROM %i: [Mode 2 Formless] Sync\n", dev->id);
	memcpy(b, raw_buffer, 12);
	cdrom_sector_size += 12;
	b += 12;
    }

    if (cdrom_sector_flags & 0x20) {	/* Header */
	cdrom_log("CD-ROM %i: [Mode 2 Formless] Header\n", dev->id);
	memcpy(b, raw_buffer + 12, 4);
	cdrom_sector_size += 4;
	b += 4;
    }

    /* Mode 1 sector, expected type is 1 type. */
    if (cdrom_sector_flags & 0x40) {	/* Sub-header */
	cdrom_log("CD-ROM %i: [Mode 2 Formless] Sub-header\n", dev->id);
	memcpy(b, raw_buffer + 16, 8);
	cdrom_sector_size += 8;
	b += 8;
    }

    if (cdrom_sector_flags & 0x10) {	/* User data */
	cdrom_log("CD-ROM %i: [Mode 2 Formless] User data\n", dev->id);
	memcpy(b, raw_buffer + 24, 2336);
	cdrom_sector_size += 2336;
	b += 2336;
    }
}


static void
read_mode2_xa_form1(cdrom_t *dev, int cdrom_sector_flags, uint32_t lba, uint32_t msf, int mode2, uint8_t *b)
{
    if ((dev->cd_status == CD_STATUS_DATA_ONLY) || (dev->ops->sector_size(dev, lba) == 2048))
	read_sector_to_buffer(dev, raw_buffer, msf, lba, mode2, 2048);
    else
	dev->ops->read_sector(dev, CD_READ_RAW, raw_buffer, lba);

    cdrom_sector_size = 0;

    if (cdrom_sector_flags & 0x80) {	/* Sync */
	cdrom_log("CD-ROM %i: [XA Mode 2 Form 1] Sync\n", dev->id);
	memcpy(b, raw_buffer, 12);
	cdrom_sector_size += 12;
	b += 12;
    }

    if (cdrom_sector_flags & 0x20) {	/* Header */
	cdrom_log("CD-ROM %i: [XA Mode 2 Form 1] Header\n", dev->id);
	memcpy(b, raw_buffer + 12, 4);
	cdrom_sector_size += 4;
	b += 4;
    }

    if (cdrom_sector_flags & 0x40) {	/* Sub-header */
	cdrom_log("CD-ROM %i: [XA Mode 2 Form 1] Sub-header\n", dev->id);
	memcpy(b, raw_buffer + 16, 8);
	cdrom_sector_size += 8;
	b += 8;
    }

    if (cdrom_sector_flags & 0x10) {	/* User data */
	cdrom_log("CD-ROM %i: [XA Mode 2 Form 1] User data\n", dev->id);
	memcpy(b, raw_buffer + 24, 2048);
	cdrom_sector_size += 2048;
	b += 2048;
    }

    if (cdrom_sector_flags & 0x08) {	/* EDC/ECC */
	cdrom_log("CD-ROM %i: [XA Mode 2 Form 1] EDC/ECC\n", dev->id);
	memcpy(b, raw_buffer + 2072, 280);
	cdrom_sector_size += 280;
	b += 280;
    }
}


static void
read_mode2_xa_form2(cdrom_t *dev, int cdrom_sector_flags, uint32_t lba, uint32_t msf, int mode2, uint8_t *b)
{
    if ((dev->cd_status == CD_STATUS_DATA_ONLY) || (dev->ops->sector_size(dev, lba) == 2324))
	read_sector_to_buffer(dev, raw_buffer, msf, lba, mode2, 2324);
    else
	dev->ops->read_sector(dev, CD_READ_RAW, raw_buffer, lba);

    cdrom_sector_size = 0;

    if (cdrom_sector_flags & 0x80) {	/* Sync */
	cdrom_log("CD-ROM %i: [XA Mode 2 Form 2] Sync\n", dev->id);
	memcpy(b, raw_buffer, 12);
	cdrom_sector_size += 12;
	b += 12;
    }

    if (cdrom_sector_flags & 0x20) {	/* Header */
	cdrom_log("CD-ROM %i: [XA Mode 2 Form 2] Header\n", dev->id);
	memcpy(b, raw_buffer + 12, 4);
	cdrom_sector_size += 4;
	b += 4;
    }

    if (cdrom_sector_flags & 0x40) {	/* Sub-header */
	cdrom_log("CD-ROM %i: [XA Mode 2 Form 2] Sub-header\n", dev->id);
	memcpy(b, raw_buffer + 16, 8);
	cdrom_sector_size += 8;
	b += 8;
    }

    if (cdrom_sector_flags & 0x10) {	/* User data */
	cdrom_log("CD-ROM %i: [XA Mode 2 Form 2] User data\n", dev->id);
	memcpy(b, raw_buffer + 24, 2328);
	cdrom_sector_size += 2328;
	b += 2328;
    }
}


int
cdrom_readsector_raw(cdrom_t *dev, uint8_t *buffer, int sector, int ismsf, int cdrom_sector_type,
		     int cdrom_sector_flags, int *len)
{
    uint8_t *b, *temp_b;
    uint32_t msf, lba;
    int audio = 0, mode2 = 0;
    int m, s, f;

    if (dev->cd_status == CD_STATUS_EMPTY)
	return 0;

    b = temp_b = buffer;

    *len = 0;

    if (ismsf) {
	m = (sector >> 16) & 0xff;
	s = (sector >> 8) & 0xff;
	f = sector & 0xff;
	lba = MSFtoLBA(m, s, f) - 150;
	msf = sector;
    } else {
	lba = sector;
	msf = cdrom_lba_to_msf_accurate(sector);
    }

    if (dev->ops->track_type)
	    audio = dev->ops->track_type(dev, lba);

    mode2 = audio & ~CD_TRACK_AUDIO;
    audio &= CD_TRACK_AUDIO;

    memset(raw_buffer, 0, 2448);
    memset(extra_buffer, 0, 296);

    if (!(cdrom_sector_flags & 0xf0)) {		/* 0x00 and 0x08 are illegal modes */
	cdrom_log("CD-ROM %i: [Mode 1] 0x00 and 0x08 are illegal modes\n", dev->id);
	return 0;
    }

    if (!track_type_is_valid(dev->id, cdrom_sector_type, cdrom_sector_flags, audio, mode2))
	return 0;

    if ((cdrom_sector_type > 5) && (cdrom_sector_type != 8)) {
	cdrom_log("CD-ROM %i: Attempting to read an unrecognized sector type from an image\n", dev->id);
	return 0;
    } else if (cdrom_sector_type == 1) {
	if (!audio || (dev->cd_status == CD_STATUS_DATA_ONLY)) {
		cdrom_log("CD-ROM %i: [Audio] Attempting to read an audio sector from a data image\n", dev->id);
		return 0;
	}

	read_audio(dev, lba, temp_b);
    } else if (cdrom_sector_type == 2) {
	if (audio || mode2) {
		cdrom_log("CD-ROM %i: [Mode 1] Attempting to read a sector of another type\n", dev->id);
		return 0;
	}

	read_mode1(dev, cdrom_sector_flags, lba, msf, mode2, temp_b);
    } else if (cdrom_sector_type == 3) {
	if (audio || !mode2 || (mode2 & 0x03)) {
		cdrom_log("CD-ROM %i: [Mode 2 Formless] Attempting to read a sector of another type\n", dev->id);
		return 0;
	}

	read_mode2_non_xa(dev, cdrom_sector_flags, lba, msf, mode2, temp_b);
    } else if (cdrom_sector_type == 4) {
	if (audio || !mode2 || ((mode2 & 0x03) != 1)) {
		cdrom_log("CD-ROM %i: [XA Mode 2 Form 1] Attempting to read a sector of another type\n", dev->id);
		return 0;
	}

	read_mode2_xa_form1(dev, cdrom_sector_flags, lba, msf, mode2, temp_b);
    } else if (cdrom_sector_type == 5) {
	if (audio || !mode2 || ((mode2 & 0x03) != 2)) {
		cdrom_log("CD-ROM %i: [XA Mode 2 Form 2] Attempting to read a sector of another type\n", dev->id);
		return 0;
	}

	read_mode2_xa_form2(dev, cdrom_sector_flags, lba, msf, mode2, temp_b);
    } else if (cdrom_sector_type == 8) {
	if (audio) {
		cdrom_log("CD-ROM %i: [Any Data] Attempting to read a data sector from an audio track\n", dev->id);
		return 0;
	}

	if (mode2 && ((mode2 & 0x03) == 1))
		read_mode2_xa_form1(dev, cdrom_sector_flags, lba, msf, mode2, temp_b);
	else if (!mode2)
		read_mode1(dev, cdrom_sector_flags, lba, msf, mode2, temp_b);
	else {
		cdrom_log("CD-ROM %i: [Any Data] Attempting to read a data sector whose cooked size is not 2048 bytes\n", dev->id);
		return 0;
	}
    } else {
	if (mode2) {
		if ((mode2 & 0x03) == 0x01)
			read_mode2_xa_form1(dev, cdrom_sector_flags, lba, msf, mode2, temp_b);
		else if ((mode2 & 0x03) == 0x02)
			read_mode2_xa_form2(dev, cdrom_sector_flags, lba, msf, mode2, temp_b);
		else
			read_mode2_non_xa(dev, cdrom_sector_flags, lba, msf, mode2, temp_b);
	} else {
		if (audio)
			read_audio(dev, lba, temp_b);
		else
			read_mode1(dev, cdrom_sector_flags, lba, msf, mode2, temp_b);
	}
    }

    if ((cdrom_sector_flags & 0x06) == 0x02) {
	/* Add error flags. */
	cdrom_log("CD-ROM %i: Error flags\n", dev->id);
	memcpy(b + cdrom_sector_size, extra_buffer, 294);
	cdrom_sector_size += 294;
    } else if ((cdrom_sector_flags & 0x06) == 0x04) {
	/* Add error flags. */
	cdrom_log("CD-ROM %i: Full error flags\n", dev->id);
	memcpy(b + cdrom_sector_size, extra_buffer, 296);
	cdrom_sector_size += 296;
    }

    if ((cdrom_sector_flags & 0x700) == 0x100) {
	cdrom_log("CD-ROM %i: Raw subchannel data\n", dev->id);
	memcpy(b + cdrom_sector_size, raw_buffer + 2352, 96);
	cdrom_sector_size += 96;
    } else if ((cdrom_sector_flags & 0x700) == 0x200) {
	cdrom_log("CD-ROM %i: Q subchannel data\n", dev->id);
	memcpy(b + cdrom_sector_size, raw_buffer + 2352, 16);
	cdrom_sector_size += 16;
    } else if ((cdrom_sector_flags & 0x700) == 0x400) {
	cdrom_log("CD-ROM %i: R/W subchannel data\n", dev->id);
	memcpy(b + cdrom_sector_size, raw_buffer + 2352, 96);
	cdrom_sector_size += 96;
    }

    *len = cdrom_sector_size;

    return 1;
}


/* Peform a master init on the entire module. */
void
cdrom_global_init(void)
{
    /* Clear the global data. */
    memset(cdrom, 0x00, sizeof(cdrom));
}


static void
cdrom_drive_reset(cdrom_t *dev)
{
    dev->priv = NULL;
    dev->insert = NULL;
    dev->close = NULL;
    dev->get_volume = NULL;
    dev->get_channel = NULL;
}


void
cdrom_hard_reset(void)
{
    cdrom_t *dev;
    int i;

    for (i = 0; i < CDROM_NUM; i++) {
	dev = &cdrom[i];
	if (dev->bus_type) {
		cdrom_log("CD-ROM %i: Hard reset\n", i);

		dev->id = i;

		cdrom_drive_reset(dev);

		switch(dev->bus_type) {
			case CDROM_BUS_ATAPI:
			case CDROM_BUS_SCSI:
				scsi_cdrom_drive_reset(i);
				break;

			default:
				break;
		}

		dev->cd_status = CD_STATUS_EMPTY;

		if (dev->host_drive == 200)
			cdrom_image_open(dev, dev->image_path);
	}
    }

    sound_cd_thread_reset();
}


void
cdrom_close(void)
{
    cdrom_t *dev;
    int i;

    for (i = 0; i < CDROM_NUM; i++) {
	dev = &cdrom[i];

	if (dev->close)
		dev->close(dev->priv);

	if (dev->ops && dev->ops->exit)
		dev->ops->exit(dev);

	dev->ops = NULL;
	dev->priv = NULL;

	cdrom_drive_reset(dev);
    }
}


/* Signal disc change to the emulated machine. */
void
cdrom_insert(uint8_t id)
{
    cdrom_t *dev = &cdrom[id];

    if (dev->bus_type) {
	if (dev->insert)
		dev->insert(dev->priv);
    }
}


/* The mechanics of ejecting a CD-ROM from a drive. */
void
cdrom_eject(uint8_t id)
{
    cdrom_t *dev = &cdrom[id];

    /* This entire block should be in cdrom.c/cdrom_eject(dev*) ... */
    if (dev->host_drive == 0) {
	/* Switch from empty to empty. Do nothing. */
	return;
    }

    if (dev->host_drive == 200)
	wcscpy(dev->prev_image_path, dev->image_path);

    dev->prev_host_drive = dev->host_drive;
    dev->host_drive = 0;

    dev->ops->exit(dev);
    dev->ops = NULL;
    memset(dev->image_path, 0, sizeof(dev->image_path));

    cdrom_insert(id);

    plat_cdrom_ui_update(id, 0);

    config_save();
}


/* The mechanics of re-loading a CD-ROM drive. */
void
cdrom_reload(uint8_t id)
{
    cdrom_t *dev = &cdrom[id];

    if ((dev->host_drive == dev->prev_host_drive) ||
	(dev->prev_host_drive == 0) || (dev->host_drive != 0)) {
	/* Switch from empty to empty. Do nothing. */
	return;
    }

    if (dev->ops && dev->ops->exit)
	dev->ops->exit(dev);
    dev->ops = NULL;
    memset(dev->image_path, 0, sizeof(dev->image_path));

    if (dev->prev_host_drive == 200) {
	/* Reload a previous image. */
	wcscpy(dev->image_path, dev->prev_image_path);
	cdrom_image_open(dev, dev->image_path);

	cdrom_insert(id);

	if (wcslen(dev->image_path) == 0)
		dev->host_drive = 0;
	  else
		dev->host_drive = 200;
    }

    plat_cdrom_ui_update(id, 1);

    config_save();
}