/* 
 * Author: Karsten Rucker (rucker@astro.uni-bonn.de) (original code)
 * All modifications in this file to the original code are
 * (C) Copyright 1992, ..., 2007 the "DOSEMU-Development-Team".
 *
 * for details see file COPYING.DOSEMU in the DOSEMU distribution
 */

/* 
 * DANG_BEGIN_MODULE
 * 
 * drivers/cdrom.c
 *
 * REMARK
 * See dosemu/doc/README.txt (7. Using CDROMS) for further information
 * /REMARK
 *
 * History:
 *   May 25, 95, Karsten Rucker (rucker@astro.uni-bonn.de)
 *   May 30, 95, Werner Zimmermann (zimmerma@rz.fht-esslingen.de)
 *   - Works with Mitsumi and Aztech/Orchid/Okano/Wearnes CDROM drives
 *   - Minor modifications in comments
 *   Dec 3, 95, lee
 *   - Debugging output changed from *printf()/error() to C_printf()
 *   - Minor editing, no real changes
 *
 * DANG_END_MODULE
 */

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <fcntl.h>
#include <sys/types.h>
#include <sys/ioctl.h>
#include <unistd.h>
#include <ctype.h>
#include <errno.h>
#ifndef ENOMEDIUM
  /* kernels < 2.0.32 don't have this defined */
  #define ENOMEDIUM       123     /* No medium found */
#endif
#ifdef __linux__
#include "Linux/cdrom.h"
#endif

#include "emu.h"
#include "dos2linux.h"

#undef CDROM_DEBUG

static int CdromFd[4] = {-1,-1,-1,-1};
static int IndexCd = -1;
#define cdrom_fd CdromFd[IndexCd]

int cdu33a = 0;

/* eject_allowed = 0
 * For Mitsumi and Aztech/Orchid/Okano/Wearnes drives, because eject.com may
 * hang thes system.
 *
 * eject_allowed = 1
 * Allows to eject the cdrom using eject.com.
 */

int eject_allowed = 1;

/*
 * From mscdex21.doc:
 *
 * The device driver will return a 32-bit value. Bit 0 is the least significant
 * bit. The bits are interpreted as follows (* = dosemu defaults):
 *
 *  Bit 0     0    Door closed
 *            1    Door open
 *  Bit 1     0    Door locked
 *            1    Door unlocked
 *  Bit 2     0    Supports only cooked reading (*)
 *            1    Supports cooked and raw reading
 *  Bit 3     0    Read only (*)
 *            1    Read/write
 *  Bit 4     0    Data read only
 *            1    Data read and plays audio/video tracks (*)
 *  Bit 5     0    No interleaving (*)
 *            1    Supports interleaving
 *  Bit 6     0    Reserved
 *  Bit 7     0    No prefetching (*)
 *            1    Supports prefetching requests
 *  Bit 8     0    No audio channel manipulation
 *            1    Supports audio channel manipulation (*)
 *  Bit 9     0    Supports HSG addressing mode
 *            1    Supports HSG and Red Book addressing modes (*)
 *  "Bit 10-31 0    Reserved (all 0)"
 *  Bit 10    0    Ignore XA directory entries (?)
 *            1    Read XA directory entries (*)(?)
 *  Bit 11    0    Disk present (?)
 *            1    No disk (?)
 *
 */
unsigned int device_status;
struct audio_status { unsigned int status;
		      unsigned char media_changed;
                      unsigned char paused_bit;
                      unsigned int last_StartSector,last_EndSector;
                      unsigned char outchan0,outchan1,outchan2,outchan3;
                      unsigned char volume0,volume1,volume2,volume3;
                    } audio_status;


#define CALC_PTR(PTR,OFFSET,RESULT_TYPE) ((RESULT_TYPE *)(PTR+OFFSET))


#define MSCD_GETVOLUMESIZE_SIZE    1

#define MSCD_READ_ADRESSING       13
#define MSCD_READ_STARTSECTOR     20
#define MSCD_READ_NUMSECTORS      18

#define MSCD_SEEK_STARTSECTOR     20

#define MSCD_PLAY_ADRESSING       13
#define MSCD_PLAY_STARTSECTOR     14
#define MSCD_PLAY_NUMSECTORS      18

#define MSCD_LOCH_ADRESSING        1
#define MSCD_LOCH_LOCATION         2

#define MSCD_DISKINFO_LTN          1
#define MSCD_DISKINFO_HTN          2
#define MSCD_DISKINFO_LEADOUT      3

#define MSCD_TRACKINFO_TRACKNUM    1
#define MSCD_TRACKINFO_TRACKPOS    2
#define MSCD_TRACKINFO_CTRL        6

#define MSCD_QCHAN_CTRL            1
#define MSCD_QCHAN_TNO             2
#define MSCD_QCHAN_IND             3
#define MSCD_QCHAN_MIN             4
#define MSCD_QCHAN_SEC             5
#define MSCD_QCHAN_FRM             6
#define MSCD_QCHAN_ZERO            7
#define MSCD_QCHAN_AMIN            8
#define MSCD_QCHAN_ASEC            9
#define MSCD_QCHAN_AFRM           10

#define MSCD_AUDSTAT_PAUSED        1
#define MSCD_AUDSTAT_START         3
#define MSCD_AUDSTAT_END           7

#define MSCD_CTRL_VOLUME0          2
#define MSCD_CTRL_VOLUME1          4
#define MSCD_CTRL_VOLUME2          6
#define MSCD_CTRL_VOLUME3          8

#ifdef __linux__
char *Path_cdrom[]={"/dev/cdrom","/dev/cdrom2","/dev/cdrom3","/dev/cdrom4"};
#endif
#define path_cdrom Path_cdrom[IndexCd]

#ifdef CDROM_DEBUG
static int logging_ioctl(int fd, unsigned int cmd, void *arg)
{
    int rval;
    int err;
    if (debug_level('C')>5)
      C_printf("CDROM: ioctl %#x\n", cmd);
    rval = ioctl(fd, cmd, arg);
    err = errno;

    if (rval == -1) {
	C_printf("CDROM: err %s\n", strerror(errno));
	errno = err;
    }
    return rval;
}

static void dump_cd_sect (char *tb)
{
    unsigned char buf[128];
    int i,j;
    unsigned char *p,*q,c;

    q=tb;
    for (i=0; i<32 && debug_level('C')>5; i++) {		/* 32x64 */
      p=buf;
      for (j=0; j<64; j++) {
        c=*q++;
        *p++ = (isprint(c)? c:'.');
      }
      C_printf("%03x[%s]\n",i*64,buf);
    }
    q=tb;
    for (i=0; i<64 && debug_level('C')>8; i++) {		/* 64x32 */
      p=buf;
      for (j=0; j<4; j++) {
        p+=sprintf(p,":%02x%02x%02x%02x%02x%02x%02x%02x",q[0],q[1],q[2],
        	q[3],q[4],q[5],q[6],q[7]);
        q+=8;
      }
      C_printf("%03x%s\n",i*32,buf);
    }
}


#define ioctl logging_ioctl
#endif

static void cdrom_reset(void)
{
  /* after a disk change a new read access will
     return an error. In order to unlock this condition
     the drive must be reopened.
     Does someone know a better way?                   */
   C_printf("CDROM: cdrom reset\n");
   close (cdrom_fd);
   cdrom_fd = open (path_cdrom, O_RDONLY | O_NONBLOCK);
   if (cdrom_fd >= 0) ioctl (cdrom_fd, CDROMRESET, NULL);
}

#define MSCD_AUDCHAN_VOLUME0       2
#define MSCD_AUDCHAN_VOLUME1       4
#define MSCD_AUDCHAN_VOLUME2       6
#define MSCD_AUDCHAN_VOLUME3       8

void cdrom_helper(unsigned char *req_buf, unsigned char *transfer_buf)
{
   unsigned int Sector_plus_150,Sector;
   struct cdrom_msf cdrom_msf;
   struct cdrom_subchnl cdrom_subchnl;
   struct cdrom_tochdr cdrom_tochdr;
   struct cdrom_tocentry cdrom_tocentry;
   struct cdrom_volctrl cdrom_volctrl;
   int n, err;

   cdrom_subchnl.cdsc_format = CDROM_MSF;

   IndexCd=(int)((HI(ax) & 0xC0)>>6);
   HI(ax) = HI(ax) & 0x3F;

   if ((cdu33a) && (cdrom_fd < 0)) {
        cdrom_fd = open (path_cdrom, O_RDONLY | O_NONBLOCK);

        if (cdrom_fd < 0) {
          switch (HI(ax)) {
            case 0x09:    /* media changed request */
              LO(bx) = 1; /* media changed */
              LO(ax) = 0;
              return;
            case 0x0A:    /* device status request */
              LWORD(ebx) = audio_status.status | 0x800; /* no disc */
              LO(ax) = 0;
              return;
          }
          LO(ax) = 1; /* for other requests return with error */
          return ;
        }
   }


   switch (HI(ax)) {
     case 0x01:	/* NOTE: you can't see XA data disks if bit 10 of status
		 * is cleared, MSCDEX will test it and skip XA entries!
		 * Actually the entries skipped must have this pattern:
		 *   xxxx1xxx xxxxxxxx 0x58 0x41
		 * and the mscdex 2.25 code is:
		 *	test	word ptr [bx+1Eh],400h
		 *	jz	[check for XA]
		 *	[return 0 = valid entry]
		 * [check for XA]
		 * ...
		 *	cmp	word ptr es:[bx+6],4158h  'XA'
		 *	jne	[return 0]
		 *	mov	ax,es:[bx+4]
		 *	and	ax,8
		 *	[return ax]
		 */
		audio_status.status = 0x00000710; /* see function 0x0A below */
                audio_status.paused_bit = 0;
                audio_status.media_changed = 0;
                audio_status.volume0 = 0xFF;
                audio_status.volume1 = 0xFF;
                audio_status.volume2 = 0;
                audio_status.volume3 = 0;
                audio_status.outchan0 = 0;
                audio_status.outchan1 = 1;
                audio_status.outchan2 = 2;
                audio_status.outchan3 = 3;

                cdrom_fd = open (path_cdrom, O_RDONLY | O_NONBLOCK);
		err = errno;

                if (cdrom_fd < 0) {
		  C_printf("CDROM: cdrom open (%s) failed: %s\n",
			    path_cdrom, strerror(err));
                  LO(ax) = 0;
                  if ((err == EIO) || (err==ENOMEDIUM)) {
                    /* drive which cannot be opened if no
                       disc is inserted!                   */
                    cdu33a = 1;
                    if (! eject_allowed)
                       LO(ax) = 1; /* no disk in drive */
                   }
                  else LO(ax) = 1; /* no cdrom drive installed */
                  if (! eject_allowed)
                    LO(ax) = 1; /* no disk in drive */
                 }
                else {
                       LO(ax) = 0;
                       if (! eject_allowed) {
                         if (ioctl (cdrom_fd, CDROMREADTOCHDR, &cdrom_tochdr))
                           if (ioctl (cdrom_fd, CDROMREADTOCHDR, &cdrom_tochdr))
                             LO(ax) = 1;
                       }
                     }
                break;
     case 0x02: /* read long */
                if (eject_allowed && ioctl (cdrom_fd, CDROMSUBCHNL, &cdrom_subchnl) && errno != ENOTTY) {
                  audio_status.media_changed = 1;
                  if (ioctl (cdrom_fd, CDROMSUBCHNL, &cdrom_subchnl)) {
                    /* no disc in drive */
                    LO(ax) = 1;
                    break;
                   }
                  else { /* disc in drive */
                       }
                }

                if (req_buf == NULL) req_buf = SEG_ADR((unsigned char *), es, di);
                if (transfer_buf == NULL) transfer_buf = SEG_ADR((unsigned char *), ds, si);

                if (*CALC_PTR(req_buf,MSCD_READ_ADRESSING,u_char) == 1) {
                  cdrom_msf.cdmsf_min0   = *CALC_PTR(req_buf,MSCD_READ_STARTSECTOR+2,u_char);
                  cdrom_msf.cdmsf_sec0   = *CALC_PTR(req_buf,MSCD_READ_STARTSECTOR+1,u_char);
                  cdrom_msf.cdmsf_frame0 = *CALC_PTR(req_buf,MSCD_READ_STARTSECTOR+0,u_char);
                  Sector = cdrom_msf.cdmsf_min0*60*75+cdrom_msf.cdmsf_sec0*75
                            +cdrom_msf.cdmsf_frame0-150;
                 }
                 else { Sector = *CALC_PTR(req_buf,MSCD_READ_STARTSECTOR,u_long);
                      }

		C_printf("CDROM: reading sector %#x (fmt %d)\n", Sector,
			  *CALC_PTR(req_buf,MSCD_READ_ADRESSING,u_char));
                if ((off_t) -1 == lseek (cdrom_fd, Sector*CD_FRAMESIZE, SEEK_SET)) {
		    HI(ax) = (errno == EINVAL ? 0x08 : 0x0F);
		    C_printf("CDROM: lseek failed: %s\n", strerror(errno));
		    LO(ax) = 1;
		} else {
		    if ( (n = unix_read (cdrom_fd, transfer_buf, *CALC_PTR(req_buf,MSCD_READ_NUMSECTORS,u_short)*CD_FRAMESIZE)) < 0) {
			/* cd must be in drive, reset drive and try again */
			cdrom_reset();
			if ((off_t) -1 == lseek (cdrom_fd, Sector*CD_FRAMESIZE, SEEK_SET)) {
			    HI(ax) = (errno == EINVAL ? 0x08 : 0x0F);
			    C_printf("CDROM: lseek failed: %s\n", strerror(errno));
			    LO(ax) = 1;
			} else
			    if ( (n = unix_read (cdrom_fd, transfer_buf, *CALC_PTR(req_buf,MSCD_READ_NUMSECTORS,u_short)*CD_FRAMESIZE)) < 0) {
				HI(ax) = (errno == EFAULT ? 0x0A : 0x0F);
				C_printf("CDROM: sector read (to %p, len %#x) failed: %s\n",
					  transfer_buf, *CALC_PTR(req_buf,MSCD_READ_NUMSECTORS,u_short)*CD_FRAMESIZE, strerror(errno));
				LO(ax) = 1;
			    } else LO(ax) = 0;
		    }
		    if (n != *CALC_PTR(req_buf,MSCD_READ_NUMSECTORS,u_short)*CD_FRAMESIZE) {
			C_printf("CDROM: sector read len %#x got %#x\n",
				  *CALC_PTR(req_buf,MSCD_READ_NUMSECTORS,u_short)*CD_FRAMESIZE, n);
			LO(ax) = 1;
			HI(ax) = 0x0F;
		    } else {
#ifdef CDROM_DEBUG
			dump_cd_sect(transfer_buf);
#endif
			LO(ax) = 0;
		    }
		}
                break;
     case 0x03: /* seek */
                req_buf = SEG_ADR((unsigned char *), es, di);
                if ((off_t)-1 == lseek (cdrom_fd, *CALC_PTR(req_buf,MSCD_SEEK_STARTSECTOR,u_long)*CD_FRAMESIZE, SEEK_SET)) {
		    C_printf("CDROM: lseek failed: %s\n", strerror(errno));
		    LO(ax) = 1;
		}
                break;
     case 0x04: /* play */
                req_buf = SEG_ADR((unsigned char *), es, di);
                if (*CALC_PTR(req_buf,MSCD_PLAY_ADRESSING,u_char) == 1) {
                  cdrom_msf.cdmsf_min0   = *CALC_PTR(req_buf,MSCD_PLAY_STARTSECTOR+2,u_char);
                  cdrom_msf.cdmsf_sec0   = *CALC_PTR(req_buf,MSCD_PLAY_STARTSECTOR+1,u_char);
                  cdrom_msf.cdmsf_frame0 = *CALC_PTR(req_buf,MSCD_PLAY_STARTSECTOR+0,u_char);
                  Sector_plus_150 = cdrom_msf.cdmsf_min0*60*75+cdrom_msf.cdmsf_sec0*75
                                      +cdrom_msf.cdmsf_frame0;
                  audio_status.last_StartSector = Sector_plus_150;
                 }
                 else { Sector_plus_150 = *CALC_PTR(req_buf,MSCD_PLAY_STARTSECTOR,u_long) + 150;
                        cdrom_msf.cdmsf_min0   = (Sector_plus_150 / (60*75));
                        cdrom_msf.cdmsf_sec0   = (Sector_plus_150 % (60*75)) / 75;
                        cdrom_msf.cdmsf_frame0 = (Sector_plus_150 % (60*75)) % 75;
                        audio_status.last_StartSector = Sector_plus_150;
                      }
                Sector_plus_150 += *CALC_PTR(req_buf,MSCD_PLAY_NUMSECTORS,u_long);
                cdrom_msf.cdmsf_min1   = (Sector_plus_150 / (60*75));
                cdrom_msf.cdmsf_sec1   = (Sector_plus_150 % (60*75)) / 75;
                cdrom_msf.cdmsf_frame1 = (Sector_plus_150 % (60*75)) % 75;

                audio_status.last_EndSector = Sector_plus_150;
                audio_status.paused_bit = 0;
                if (ioctl (cdrom_fd, CDROMPLAYMSF, &cdrom_msf)) {
                  audio_status.media_changed = 1;
                  if (ioctl (cdrom_fd, CDROMPLAYMSF, &cdrom_msf)) {
                    /* no disk in drive */
                    LO(ax) = 1;
                    break;
                  }
                }
                LO(ax) = 0;
                break;
     case 0x05: /* pause (stop) audio */
                LO(ax) = 0;
                if (ioctl (cdrom_fd, CDROMSUBCHNL, &cdrom_subchnl) == 0) {
                  if (cdrom_subchnl.cdsc_audiostatus == CDROM_AUDIO_PLAY) {
                    audio_status.last_StartSector =
                                cdrom_subchnl.cdsc_absaddr.msf.minute*60*75
                                +cdrom_subchnl.cdsc_absaddr.msf.second*75
                                +cdrom_subchnl.cdsc_absaddr.msf.frame;
                    ioctl (cdrom_fd, CDROMPAUSE, NULL);
                    audio_status.paused_bit = 1;
                   }
                  else { audio_status.last_StartSector = 0;
                         audio_status.last_EndSector = 0;
                         audio_status.paused_bit = 0;
                       }
                 }
                 else { audio_status.last_StartSector = 0;
                        audio_status.last_EndSector = 0;
                        audio_status.paused_bit = 0;
                        audio_status.media_changed = 1;
                      }
                break;
     case 0x06: /* resume audio */
                LO(ax) = 0;
                if (audio_status.paused_bit) {
                  if (ioctl (cdrom_fd, CDROMRESUME, NULL) == 0) {
                    audio_status.paused_bit = 0;
                    HI(ax) = 1;
                  }
                 }
                else LO(ax) = 1;
                break;
     case 0x07: /* location of head */
                LWORD(eax) = 0;
                if (ioctl (cdrom_fd, CDROMSUBCHNL, &cdrom_subchnl)) {
                  audio_status.media_changed = 1;
                  if (ioctl (cdrom_fd, CDROMSUBCHNL, &cdrom_subchnl)) {
                    /* no disk in drive */
                    LO(ax) = 1;
                    break;
                  }
                }
                if (cdrom_subchnl.cdsc_audiostatus == CDROM_AUDIO_PLAY)
                  HI(ax) = 1;

                req_buf = SEG_ADR((unsigned char *), ds, si);
                if (*CALC_PTR(req_buf,MSCD_LOCH_ADRESSING,u_char) == 0) {
                  *CALC_PTR(req_buf,MSCD_LOCH_LOCATION,u_long)
                     = cdrom_subchnl.cdsc_absaddr.msf.minute*60*75
                            +cdrom_subchnl.cdsc_absaddr.msf.second*75
                             +cdrom_subchnl.cdsc_absaddr.msf.frame-150;
                 }
                 else {/* red book adressing */
                       *CALC_PTR(req_buf,MSCD_LOCH_LOCATION+3,u_char) = 0;
                       *CALC_PTR(req_buf,MSCD_LOCH_LOCATION+2,u_char) = cdrom_subchnl.cdsc_absaddr.msf.minute;
                       *CALC_PTR(req_buf,MSCD_LOCH_LOCATION+1,u_char) = cdrom_subchnl.cdsc_absaddr.msf.second;
                       *CALC_PTR(req_buf,MSCD_LOCH_LOCATION+0,u_char) = cdrom_subchnl.cdsc_absaddr.msf.frame;
                      }
                break;
     case 0x08: /* return sectorsize */
                LO(ax) = 0;
                LWORD(ebx) = CD_FRAMESIZE;
                break;
     case 0x09: /* media changed */
                /* this function will be called from MSCDEX before
                   each new disk access !                         */
                HI(ax) = 0; LO(ax) = 0; LO(bx) = 0;
		C_printf("CDROM: media changed?  %#x\n", audio_status.media_changed);
		errno = 0;
		if (eject_allowed) {
                  if ((audio_status.media_changed) ||
                        ioctl (cdrom_fd, CDROMSUBCHNL, &cdrom_subchnl)) {
		    if (errno == EIO)
			cdrom_reset();
                    audio_status.media_changed = 0;
                    LO(bx) = 1; /* media has been changed */
		    C_printf("CDROM: media changed?  yes\n");
                    ioctl (cdrom_fd, CDROMSUBCHNL, &cdrom_subchnl);
                    if (! ioctl (cdrom_fd, CDROMSUBCHNL, &cdrom_subchnl))
                      cdrom_reset(); /* disc in drive */
                   }
                   else /* media has not changed, check audio status */
                        if (cdrom_subchnl.cdsc_audiostatus == CDROM_AUDIO_PLAY)
                          HI(ax) = 1; /* audio playing in progress */
                }
                break;
     case 0x0A: /* device status */
                HI(ax) = 0; LO(ax) = 0;
                if (eject_allowed) {
                  if (ioctl (cdrom_fd, CDROMSUBCHNL, &cdrom_subchnl)) {
                    if (ioctl (cdrom_fd, CDROMSUBCHNL, &cdrom_subchnl))
                      { /* no disk in drive */
                        LWORD(ebx) = audio_status.status | 0x800;
			C_printf("CDROM: subch failed: %s\n", strerror(errno));
                        break;
                      }
                    else cdrom_reset();
		  }
                }
                /* disk in drive */
                LWORD(ebx) = audio_status.status;
                if (cdrom_subchnl.cdsc_audiostatus == CDROM_AUDIO_PLAY)
                  HI(ax) = 1;
                break;
     case 0x0B: /* drive reset */
                LO(ax) = 0;
                break;
     case 0x0C: /* lock/unlock door */
                cdrom_reset();
                if (LO(bx) == 1)
                  audio_status.status &= 0xFFFFFFFD;
                 else audio_status.status |= 0x2;
                LO(ax) = 0;
                break;
     case 0x0D: /* eject */
                LO(ax) = 0;
                if ((eject_allowed) && (audio_status.status & 0x02)) /* drive unlocked ? */
                {
                  audio_status.media_changed = 1;
                  if (ioctl (cdrom_fd, CDROMEJECT)) {
                    LO(ax) = errno;
		  }
                }
                break;
     case 0x0E: /* close tray */
                LO(ax) = 0;
                if ((eject_allowed) && (audio_status.status & 0x02)) /* drive unlocked ? */
                {
                  audio_status.media_changed = 1;
                  if (ioctl (cdrom_fd, CDROMCLOSETRAY)) {
                    LO(ax) = errno;
		  }
                }
                break;
     case 0x0F: /* audio channel control */
                LWORD(eax) = 0;
                if (ioctl (cdrom_fd, CDROMSUBCHNL, &cdrom_subchnl)) {
                  audio_status.media_changed = 1;
                  if (ioctl (cdrom_fd, CDROMSUBCHNL, &cdrom_subchnl)) {
                    /* no disk in drive */
                    LO(ax) = 1;
                    break;
                  }
                }
                if (cdrom_subchnl.cdsc_audiostatus == CDROM_AUDIO_PLAY)
                  HI(ax) = 1;

                req_buf = SEG_ADR((unsigned char *), ds, si);
                cdrom_volctrl.channel0 = *CALC_PTR(req_buf, MSCD_CTRL_VOLUME0, u_char);
                cdrom_volctrl.channel1 = *CALC_PTR(req_buf, MSCD_CTRL_VOLUME1, u_char);
                cdrom_volctrl.channel2 = *CALC_PTR(req_buf, MSCD_CTRL_VOLUME2, u_char);
                cdrom_volctrl.channel3 = *CALC_PTR(req_buf, MSCD_CTRL_VOLUME3, u_char);
                audio_status.volume0 = cdrom_volctrl.channel0;
                audio_status.volume1 = cdrom_volctrl.channel1;
                audio_status.volume2 = cdrom_volctrl.channel2;
                audio_status.volume3 = cdrom_volctrl.channel3;
                audio_status.outchan0 = *CALC_PTR(req_buf, MSCD_CTRL_VOLUME0-1, u_char);
                audio_status.outchan1 = *CALC_PTR(req_buf, MSCD_CTRL_VOLUME1-1, u_char);
                audio_status.outchan2 = *CALC_PTR(req_buf, MSCD_CTRL_VOLUME2-1, u_char);
                audio_status.outchan3 = *CALC_PTR(req_buf, MSCD_CTRL_VOLUME3-1, u_char);
                ioctl (cdrom_fd, CDROMVOLCTRL, &cdrom_volctrl);
                break;
     case 0x10: /* audio disk info */
                LWORD(eax) = 0;
                if (ioctl (cdrom_fd, CDROMREADTOCHDR, &cdrom_tochdr)) {
                  audio_status.media_changed = 1;
                  if (ioctl (cdrom_fd, CDROMREADTOCHDR, &cdrom_tochdr)) {
                    /* no disk in drive */
                    LO(ax) = 1;
                    break;
                  }
                }

                req_buf = SEG_ADR((unsigned char *), ds, si);
                *CALC_PTR(req_buf,MSCD_DISKINFO_LTN,u_char) = cdrom_tochdr.cdth_trk0;
                *CALC_PTR(req_buf,MSCD_DISKINFO_HTN,u_char) = cdrom_tochdr.cdth_trk1;
                cdrom_tocentry.cdte_track = CDROM_LEADOUT;
                cdrom_tocentry.cdte_format = CDROM_MSF;
                if (ioctl (cdrom_fd, CDROMREADTOCENTRY, &cdrom_tocentry)) {
                  C_printf ("Fatal cdrom error(audio disk info); read toc header succeeded but following read entry didn't\n");
                  LO(ax) = 1;
                  break;
                }
#ifdef __linux__
                *CALC_PTR(req_buf,MSCD_DISKINFO_LEADOUT+3,u_char) = 0;
                *CALC_PTR(req_buf,MSCD_DISKINFO_LEADOUT+2,u_char) = cdrom_tocentry.cdte_addr.msf.minute;
                *CALC_PTR(req_buf,MSCD_DISKINFO_LEADOUT+1,u_char) = cdrom_tocentry.cdte_addr.msf.second;
                *CALC_PTR(req_buf,MSCD_DISKINFO_LEADOUT+0,u_char) = cdrom_tocentry.cdte_addr.msf.frame;
#endif
                break;
     case 0x11: /* track info */
                req_buf = SEG_ADR((unsigned char *), ds, si);
                cdrom_tocentry.cdte_track = *CALC_PTR(req_buf,MSCD_TRACKINFO_TRACKNUM,u_char);
                cdrom_tocentry.cdte_format = CDROM_MSF;
		C_printf("CDROM: track info, track %d\n", cdrom_tocentry.cdte_track);
                if (ioctl (cdrom_fd, CDROMREADTOCENTRY, &cdrom_tocentry)) {
		    /* XXX MSCDEX reads beyond the end of existing tracks.  Sigh. */
		    if (errno != EINVAL)
			audio_status.media_changed = 1;
                  if (ioctl (cdrom_fd, CDROMREADTOCENTRY, &cdrom_tocentry)) {
		      if (errno == EIO) {
			  audio_status.media_changed = 1;
			  /* no disk in drive */
		      }
		      LO(ax) = 1;
                    break;
                  }
                }
#ifdef __linux__
                *CALC_PTR(req_buf,MSCD_TRACKINFO_TRACKPOS+3,u_char) = 0;
                *CALC_PTR(req_buf,MSCD_TRACKINFO_TRACKPOS+2,u_char) = cdrom_tocentry.cdte_addr.msf.minute;
                *CALC_PTR(req_buf,MSCD_TRACKINFO_TRACKPOS+1,u_char) = cdrom_tocentry.cdte_addr.msf.second;
                *CALC_PTR(req_buf,MSCD_TRACKINFO_TRACKPOS+0,u_char) = cdrom_tocentry.cdte_addr.msf.frame;
#endif
                *CALC_PTR(req_buf,MSCD_TRACKINFO_CTRL,u_char) = cdrom_tocentry.cdte_ctrl << 4 | 0x20;
                LO(ax) = 0;
                break;
     case 0x12: /* volume size */
                cdrom_tocentry.cdte_track = CDROM_LEADOUT;
                cdrom_tocentry.cdte_format = CDROM_MSF;
                if (ioctl (cdrom_fd, CDROMREADTOCENTRY, &cdrom_tocentry)) {
                  audio_status.media_changed = 1;
                  if (ioctl (cdrom_fd, CDROMREADTOCENTRY, &cdrom_tocentry)) {
                    /* no disk in drive */
                    LO(ax) = 1;
                    break;
                  }
                }
                req_buf = SEG_ADR((unsigned char *), ds, si);
#ifdef __linux__
                *CALC_PTR(req_buf,MSCD_GETVOLUMESIZE_SIZE,int) = cdrom_tocentry.cdte_addr.msf.minute*60*75
                                                                    +cdrom_tocentry.cdte_addr.msf.second*60
                                                                    +cdrom_tocentry.cdte_addr.msf.frame;
#endif
                LO(ax) = 0;
                break;
     case 0x13: /* q channel */
                LWORD(eax) = 0;
                if (ioctl (cdrom_fd, CDROMSUBCHNL, &cdrom_subchnl)) {
                  audio_status.media_changed = 1;
                  if (ioctl (cdrom_fd, CDROMSUBCHNL, &cdrom_subchnl)) {
                    /* no disk in drive */
                    LO(ax) = 1;
                    break;
                  }
                }
                if (cdrom_subchnl.cdsc_audiostatus == CDROM_AUDIO_PLAY)
                  HI(ax) = 1;

                req_buf = SEG_ADR((unsigned char *), ds, si);
                *CALC_PTR(req_buf,MSCD_QCHAN_CTRL,u_char) = (cdrom_subchnl.cdsc_adr << 4) + (cdrom_subchnl.cdsc_ctrl);
                *CALC_PTR(req_buf,MSCD_QCHAN_TNO,u_char)  = cdrom_subchnl.cdsc_trk;
                *CALC_PTR(req_buf,MSCD_QCHAN_IND,u_char)  = cdrom_subchnl.cdsc_ind;
#ifdef __linux__
                *CALC_PTR(req_buf,MSCD_QCHAN_MIN,u_char)  = cdrom_subchnl.cdsc_reladdr.msf.minute;
                *CALC_PTR(req_buf,MSCD_QCHAN_SEC,u_char)  = cdrom_subchnl.cdsc_reladdr.msf.second;
                *CALC_PTR(req_buf,MSCD_QCHAN_FRM,u_char)  = cdrom_subchnl.cdsc_reladdr.msf.frame;
#endif
                *CALC_PTR(req_buf,MSCD_QCHAN_ZERO,u_char) = 0;
                *CALC_PTR(req_buf,MSCD_QCHAN_AMIN,u_char) = cdrom_subchnl.cdsc_absaddr.msf.minute;
                *CALC_PTR(req_buf,MSCD_QCHAN_ASEC,u_char) = cdrom_subchnl.cdsc_absaddr.msf.second;
                *CALC_PTR(req_buf,MSCD_QCHAN_AFRM,u_char) = cdrom_subchnl.cdsc_absaddr.msf.frame;
                break;
     case 0x14: /* audio status */
                LWORD(eax) = 0;
                if (ioctl (cdrom_fd, CDROMSUBCHNL, &cdrom_subchnl)) {
                  audio_status.media_changed = 1;
                  if (ioctl (cdrom_fd, CDROMSUBCHNL, &cdrom_subchnl)) {
                    /* no disk in drive */
                    LO(ax) = 1;
                    break;
                  }
                }
                if (cdrom_subchnl.cdsc_audiostatus == CDROM_AUDIO_PLAY)
                  HI(ax) = 1;

                req_buf = SEG_ADR((unsigned char *), ds, si);
                *CALC_PTR(req_buf,MSCD_AUDSTAT_PAUSED,u_short)= audio_status.paused_bit;
                *CALC_PTR(req_buf,MSCD_AUDSTAT_START ,u_long) = audio_status.last_StartSector;
                *CALC_PTR(req_buf,MSCD_AUDSTAT_END   ,u_long) = audio_status.last_EndSector;
                break;
     case 0x15: /* get audio channel information */
                LWORD(eax) = 0;
                if (ioctl (cdrom_fd, CDROMSUBCHNL, &cdrom_subchnl)) {
                  audio_status.media_changed = 1;
                  if (ioctl (cdrom_fd, CDROMSUBCHNL, &cdrom_subchnl)) {
                    /* no disk in drive */
                    LO(ax) = 1;
                    break;
                  }
                }
                if (cdrom_subchnl.cdsc_audiostatus == CDROM_AUDIO_PLAY)
                  HI(ax) = 1;

                req_buf = SEG_ADR((unsigned char *), ds, si);
                *CALC_PTR(req_buf,MSCD_AUDCHAN_VOLUME0,u_char) = audio_status.volume0;
                *CALC_PTR(req_buf,MSCD_AUDCHAN_VOLUME1,u_char) = audio_status.volume1;
                *CALC_PTR(req_buf,MSCD_AUDCHAN_VOLUME2,u_char) = audio_status.volume2;
                *CALC_PTR(req_buf,MSCD_AUDCHAN_VOLUME3,u_char) = audio_status.volume3;
                *CALC_PTR(req_buf,MSCD_AUDCHAN_VOLUME0-1,u_char) = audio_status.outchan0;
                *CALC_PTR(req_buf,MSCD_AUDCHAN_VOLUME1-1,u_char) = audio_status.outchan1;
                *CALC_PTR(req_buf,MSCD_AUDCHAN_VOLUME2-1,u_char) = audio_status.outchan2;
                *CALC_PTR(req_buf,MSCD_AUDCHAN_VOLUME3-1,u_char) = audio_status.outchan3;
                break;
     default: C_printf ("CDROM: unknown request %#x!\n",HI(ax));
   }

#ifdef CDROM_DEBUG
   if (debug_level('C')>5) {
     C_printf ("CDROM: req_buf ");
     req_buf = SEG_ADR((char *), es, di);
     for (n = 0; n < 22; ++n)
       C_printf ("%02x", req_buf[n]);
       C_printf ("\n");
     }
#endif
   C_printf ("Leave cdrom request with return status %#x\n", LWORD(eax));
   return;
}
