AmigActive 25/AACD 25.iso/AACD/Utilities/BasiliskII/src/AmigaOS/sys_amiga.cpp

C/C++ Source or Header | 2001-02-02 | 24.1 KB | 1,061 lines

/*
 *  sys_amiga.cpp - System dependent routines, Amiga implementation
 *
 *  Basilisk II (C) 1997-2001 Christian Bauer
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

#include <exec/types.h>
#include <exec/memory.h>
#include <devices/newstyle.h>
#include <devices/trackdisk.h>
#include <devices/scsidisk.h>
#include <resources/disk.h>
#include <proto/dos.h>
#include <proto/exec.h>
#include <proto/disk.h>

#include "sysdeps.h"
#include "main.h"
#include "macos_util.h"
#include "prefs.h"
#include "user_strings.h"
#include "sys.h"

#define DEBUG 0
#include "debug.h"


// File handles are pointers to these structures
struct file_handle {
    bool is_file;            // Flag: plain file or /dev/something?
    bool read_only;            // Copy of Sys_open() flag
    loff_t start_byte;        // Size of file header (if any)
    loff_t size;            // Size of file/device (minus header)

    BPTR f;                    // AmigaDOS file handle (if is_file == true)

    struct IOStdReq *io;    // Pointer to IORequest (if is_file == false)
    ULONG block_size;        // Block size of device (must be a power of two)
    bool is_nsd;            // New style device?
    bool does_64bit;        // Supports 64 bit trackdisk commands?
    bool is_ejected;        // Volume has been (logically) ejected
    bool is_2060scsi;        // Enable workaround for 2060scsi.device CD-ROM TD_READ bug
};


// FileInfoBlock (must be global because it has to be on a longword boundary)
static struct FileInfoBlock FIB;

// Message port for device communication
static struct MsgPort *the_port = NULL;

// Temporary buffer in chip memory
const int TMP_BUF_SIZE = 0x10000;
static UBYTE *tmp_buf = NULL;


/*
 *  Initialization
 */

void SysInit(void)
{
    // Create port and temporary buffer
    the_port = CreateMsgPort();
    tmp_buf = (UBYTE *)AllocMem(TMP_BUF_SIZE, MEMF_CHIP | MEMF_PUBLIC);
    if (the_port == NULL || tmp_buf == NULL) {
        ErrorAlert(GetString(STR_NO_MEM_ERR));
        QuitEmulator();
    }
}


/*
 *  Deinitialization
 */

void SysExit(void)
{
    // Delete port and temporary buffer
    if (the_port) {
        DeleteMsgPort(the_port);
        the_port = NULL;
    }
    if (tmp_buf) {
        FreeMem(tmp_buf, TMP_BUF_SIZE);
        tmp_buf = NULL;
    }
}


/*
 *  This gets called when no "floppy" prefs items are found
 *  It scans for available floppy drives and adds appropriate prefs items
 */

void SysAddFloppyPrefs(void)
{
    for (int i=0; i<4; i++) {
        ULONG id = GetUnitID(i);
        if (id == DRT_150RPM) {    // We need an HD drive
            char str[256];
            sprintf(str, "/dev/mfm.device/%d/0/0/2880/512", i);
            PrefsAddString("floppy", str);
        }
    }
}


/*
 *  This gets called when no "disk" prefs items are found
 *  It scans for available HFS volumes and adds appropriate prefs items
 */

void SysAddDiskPrefs(void)
{
    // AmigaOS doesn't support MacOS partitioning, so this probably doesn't make much sense...
}


/*
 *  This gets called when no "cdrom" prefs items are found
 *  It scans for available CD-ROM drives and adds appropriate prefs items
 */

void SysAddCDROMPrefs(void)
{
    // Don't scan for drives if nocdrom option given
    if (PrefsFindBool("nocdrom"))
        return;

    //!!
}


/*
 *  Add default serial prefs (must be added, even if no ports present)
 */

void SysAddSerialPrefs(void)
{
    PrefsAddString("seriala", "serial.device/0");
    PrefsAddString("serialb", "*parallel.device/0");
}


/*
 *  Open file/device, create new file handle (returns NULL on error)
 *
 *  Format for device names: /dev/<name>/<unit>/<open flags>/<start block>/<size (blocks)>/<block size>
 */

void *Sys_open(const char *name, bool read_only)
{
    bool is_file = (strstr(name, "/dev/") != name);

    D(bug("Sys_open(%s, %s)\n", name, read_only ? "read-only" : "read/write"));

    // File or device?
    if (is_file) {

        // File, open it and get stats
        BPTR f = Open((char *)name, MODE_OLDFILE);
        if (!f)
            return NULL;
        if (!ExamineFH(f, &FIB)) {
            Close(f);
            return NULL;
        }

        // Check if file is write protected
        if (FIB.fib_Protection & FIBF_WRITE)
            read_only = true;

        // Create file_handle
        file_handle *fh = new file_handle;
        fh->f = f;
        fh->is_file = true;
        fh->read_only = read_only;

        // Detect disk image file layout
        loff_t size = FIB.fib_Size;
        Seek(fh->f, 0, OFFSET_BEGINNING);
        Read(fh->f, tmp_buf, 256);
        FileDiskLayout(size, tmp_buf, fh->start_byte, fh->size);
        return fh;

    } else {

        // Device, parse string
        char dev_name[256];
        ULONG dev_unit = 0, dev_flags = 0, dev_start = 0, dev_size = 16, dev_bsize = 512;
        if (sscanf(name, "/dev/%[^/]/%ld/%ld/%ld/%ld/%ld", dev_name, &dev_unit, &dev_flags, &dev_start, &dev_size, &dev_bsize) < 2)
            return NULL;

        // Create IORequest
        struct IOStdReq *io = (struct IOStdReq *)CreateIORequest(the_port, sizeof(struct IOExtTD));
        if (io == NULL)
            return NULL;

        // Open device
        if (OpenDevice((UBYTE *)dev_name, dev_unit, (struct IORequest *)io, dev_flags)) {
            D(bug(" couldn't open device\n"));
            DeleteIORequest(io);
            return NULL;
        }

        // Check for new style device
        bool is_nsd = false, does_64bit = false;
        struct NSDeviceQueryResult nsdqr;
        nsdqr.DevQueryFormat = 0;
        nsdqr.SizeAvailable = 0;
        io->io_Command = NSCMD_DEVICEQUERY;
        io->io_Length = sizeof(nsdqr);
        io->io_Data = (APTR)&nsdqr;
        LONG error = DoIO((struct IORequest *)io);
        D(bug("DEVICEQUERY returned %ld (length %ld, actual %ld)\n", error, io->io_Length, io->io_Actual));
        if ((!error) && (io->io_Actual >= 16) && (io->io_Actual <= sizeof(nsdqr)) && (nsdqr.SizeAvailable == io->io_Actual)) {

            // Looks like an NSD
            is_nsd = true;
            D(bug(" new style device, type %ld\n", nsdqr.DeviceType));

            // We only work with trackdisk-like devices
            if (nsdqr.DeviceType != NSDEVTYPE_TRACKDISK) {
                CloseDevice((struct IORequest *)io);
                DeleteIORequest(io);
                return NULL;
            }

            // Check whether device is 64 bit capable
            UWORD *cmdcheck;
            for (cmdcheck = nsdqr.SupportedCommands; *cmdcheck; cmdcheck++) {
                if (*cmdcheck == NSCMD_TD_READ64) {
                    D(bug(" supports 64 bit commands\n"));
                    does_64bit = true;
                }
            }
        }

        // Create file_handle
        file_handle *fh = new file_handle;
        fh->io = io;
        fh->is_file = false;
        fh->read_only = read_only;
        fh->start_byte = (loff_t)dev_start * dev_bsize;
        fh->size = (loff_t)dev_size * dev_bsize;
        fh->block_size = dev_bsize;
        fh->is_nsd = is_nsd;
        fh->does_64bit = does_64bit;
        fh->is_ejected = false;
        fh->is_2060scsi = (strcmp(dev_name, "2060scsi.device") == 0);
        return fh;
    }
}


/*
 *  Close file/device, delete file handle
 */

void Sys_close(void *arg)
{
    file_handle *fh = (file_handle *)arg;
    if (!fh)
        return;

    D(bug("Sys_close(%08lx)\n", arg));

    // File or device?
    if (fh->is_file) {

        // File, simply close it
        Close(fh->f);

    } else {

        // Device, close it and delete IORequest
        fh->io->io_Command = CMD_UPDATE;
        DoIO((struct IORequest *)fh->io);

        fh->io->io_Command = TD_MOTOR;
        fh->io->io_Length = 0;
        DoIO((struct IORequest *)fh->io);

        CloseDevice((struct IORequest *)fh->io);
        DeleteIORequest(fh->io);
    }
    delete fh;
}


/*
 *  Send one I/O request, using 64-bit addressing if the device supports it
 */

static loff_t send_io_request(file_handle *fh, bool writing, ULONG length, loff_t offset, APTR data)
{
    if (fh->does_64bit) {
        fh->io->io_Command = writing ? NSCMD_TD_WRITE64 : NSCMD_TD_READ64;
        fh->io->io_Actual = offset >> 32;
    } else {
        fh->io->io_Command = writing ? CMD_WRITE : CMD_READ;
        fh->io->io_Actual = 0;
    }
    fh->io->io_Length = length;
    fh->io->io_Offset = offset;
    fh->io->io_Data = data;

    if (fh->is_2060scsi && fh->block_size == 2048) {

        // 2060scsi.device has serious problems reading CD-ROMs via TD_READ
        static struct SCSICmd scsi;
        const int SENSE_LENGTH = 256;
        static UBYTE sense_buffer[SENSE_LENGTH];        // Buffer for autosense data
        static UBYTE cmd_buffer[10] = { 0x28, 0, 0, 0, 0, 0, 0, 0, 0, 0 };

        D(bug("send_io_request length=%lu  offset=%lu\n", length, (ULONG) offset));

        memset(sense_buffer, 0, sizeof(sense_buffer));

        scsi.scsi_Command = cmd_buffer;
        scsi.scsi_CmdLength = sizeof(cmd_buffer);
        scsi.scsi_SenseData = sense_buffer;
        scsi.scsi_SenseLength = SENSE_LENGTH;
        scsi.scsi_Flags = SCSIF_AUTOSENSE | (writing ? SCSIF_WRITE : SCSIF_READ);
        scsi.scsi_Data = (UWORD  *) data;
        scsi.scsi_Length = length;

        ULONG block_offset = (ULONG) offset / fh->block_size;
        ULONG block_length = length / fh->block_size;

        cmd_buffer[2] = block_offset >> 24;
        cmd_buffer[3] = block_offset >> 16;
        cmd_buffer[4] = block_offset >> 8;
        cmd_buffer[5] = block_offset & 0xff;

        cmd_buffer[7] = block_length >> 8;
        cmd_buffer[8] = block_length & 0xff;

        fh->io->io_Command = HD_SCSICMD;
        fh->io->io_Actual = 0;
        fh->io->io_Offset = 0;
        fh->io->io_Data = &scsi;
        fh->io->io_Length = sizeof(scsi);

        BYTE result = DoIO((struct IORequest *)fh->io);

        if (result) {
            D(bug("send_io_request SCSI FAIL result=%lu\n", result));

            if (result == HFERR_BadStatus) {
                D(bug("send_io_request SCSI Status=%lu\n", scsi.scsi_Status));
                if (scsi.scsi_Status == 2) {
                    D(bug("send_io_request Sense Key=%02lx\n", sense_buffer[2] & 0x0f));
                    D(bug("send_io_request ASC=%02lx  ASCQ=%02lx\n", sense_buffer[12], sense_buffer[13]));
                }
            }
            return 0;
        }

        D(bug("send_io_request SCSI Actual=%lu\n", scsi.scsi_Actual));

        if (scsi.scsi_Actual != length)
            return 0;

        return scsi.scsi_Actual;

    } else {

        if (DoIO((struct IORequest *)fh->io) || fh->io->io_Actual != length)
            return 0;
        return fh->io->io_Actual;
    }
}


/*
 *  Read "length" bytes from file/device, starting at "offset", to "buffer",
 *  returns number of bytes read (or 0)
 */

size_t Sys_read(void *arg, void *buffer, loff_t offset, size_t length)
{
    file_handle *fh = (file_handle *)arg;
    if (!fh)
        return 0;

    // File or device?
    if (fh->is_file) {

        // File, seek to position
        if (Seek(fh->f, offset + fh->start_byte, OFFSET_BEGINNING) == -1)
            return 0;

        // Read data
        LONG actual = Read(fh->f, buffer, length);
        if (actual == -1)
            return 0;
        else
            return actual;

    } else {

        // Device, pre-read (partial read of first block) necessary?
        loff_t pos = offset + fh->start_byte;
        size_t actual = 0;
        uint32 pre_offset = pos % fh->block_size;
        if (pre_offset) {

            // Yes, read one block
            if (send_io_request(fh, false, fh->block_size, pos - pre_offset, tmp_buf) == 0)
                return 0;

            // Copy data to destination buffer
            size_t pre_length = fh->block_size - pre_offset;
            if (pre_length > length)
                pre_length = length;
            memcpy(buffer, tmp_buf + pre_offset, pre_length);

            // Adjust data pointers
            buffer = (uint8 *)buffer + pre_length;
            pos += pre_length;
            length -= pre_length;
            actual += pre_length;
        }

        // Main read (complete reads of middle blocks) possible?
        if (length >= fh->block_size) {

            // Yes, read blocks
            size_t main_length = length & ~(fh->block_size - 1);
            if (send_io_request(fh, false, main_length, pos, buffer) == 0)
                return 0;

            // Adjust data pointers
            buffer = (uint8 *)buffer + main_length;
            pos += main_length;
            length -= main_length;
            actual += main_length;
        }

        // Post-read (partial read of last block) necessary?
        if (length) {

            // Yes, read one block
            if (send_io_request(fh, false, fh->block_size, pos, tmp_buf) == 0)
                return 0;

            // Copy data to destination buffer
            memcpy(buffer, tmp_buf, length);
            actual += length;
        }

        return actual;
    }
}


/*
 *  Write "length" bytes from "buffer" to file/device, starting at "offset",
 *  returns number of bytes written (or 0)
 */

size_t Sys_write(void *arg, void *buffer, loff_t offset, size_t length)
{
    file_handle *fh = (file_handle *)arg;
    if (!fh)
        return 0;

    // File or device?
    if (fh->is_file) {

        // File, seek to position if necessary
        if (Seek(fh->f, offset + fh->start_byte, OFFSET_BEGINNING) == -1)
            return 0;

        // Write data
        LONG actual = Write(fh->f, buffer, length);
        if (actual == -1)
            return 0;
        else
            return actual;

    } else {

        // Device, pre-write (partial write of first block) necessary
        loff_t pos = offset + fh->start_byte;
        size_t actual = 0;
        uint32 pre_offset = pos % fh->block_size;
        if (pre_offset) {

            // Yes, read one block
            if (send_io_request(fh, false, fh->block_size, pos - pre_offset, tmp_buf) == 0)
                return 0;

            // Copy data from source buffer
            size_t pre_length = fh->block_size - pre_offset;
            if (pre_length > length)
                pre_length = length;
            memcpy(tmp_buf + pre_offset, buffer, pre_length);

            // Write block back
            if (send_io_request(fh, true, fh->block_size, pos - pre_offset, tmp_buf) == 0)
                return 0;

            // Adjust data pointers
            buffer = (uint8 *)buffer + pre_length;
            pos += pre_length;
            length -= pre_length;
            actual += pre_length;
        }

        // Main write (complete writes of middle blocks) possible?
        if (length >= fh->block_size) {

            // Yes, write blocks
            size_t main_length = length & ~(fh->block_size - 1);
            if (send_io_request(fh, true, main_length, pos, buffer) == 0)
                return 0;

            // Adjust data pointers
            buffer = (uint8 *)buffer + main_length;
            pos += main_length;
            length -= main_length;
            actual += main_length;
        }

        // Post-write (partial write of last block) necessary?
        if (length) {

            // Yes, read one block
            if (send_io_request(fh, false, fh->block_size, pos, tmp_buf) == 0)
                return 0;

            // Copy data from source buffer
            memcpy(buffer, tmp_buf, length);

            // Write block back
            if (send_io_request(fh, true, fh->block_size, pos, tmp_buf) == 0)
                return 0;
            actual += length;
        }

        return actual;
    }
}


/*
 *  Return size of file/device (minus header)
 */

loff_t SysGetFileSize(void *arg)
{
    file_handle *fh = (file_handle *)arg;
    if (!fh)
        return true;

    return fh->size;
}


/*
 *  Eject volume (if applicable)
 */

void SysEject(void *arg)
{
    file_handle *fh = (file_handle *)arg;
    if (!fh)
        return;

    if (!fh->is_file) {

        // Flush buffer, turn off the drive motor and eject volume
        fh->io->io_Command = CMD_UPDATE;
        DoIO((struct IORequest *)fh->io);

        fh->io->io_Command = TD_MOTOR;
        fh->io->io_Length = 0;
        DoIO((struct IORequest *)fh->io);

        fh->io->io_Command = TD_EJECT;
        fh->io->io_Length = 1;
        DoIO((struct IORequest *)fh->io);

        fh->is_ejected = true;
    }
}


/*
 *  Format volume (if applicable)
 */

bool SysFormat(void *arg)
{
    file_handle *fh = (file_handle *)arg;
    if (!fh)
        return false;

    //!!
    return true;
}


/*
 *  Check if file/device is read-only (this includes the read-only flag on Sys_open())
 */

bool SysIsReadOnly(void *arg)
{
    file_handle *fh = (file_handle *)arg;
    if (!fh)
        return true;

    if (fh->is_file) {

        // File, return flag given to Sys_open
        return fh->read_only;

    } else {

        // Device, check write protection
        fh->io->io_Command = TD_PROTSTATUS;
        DoIO((struct IORequest *)fh->io);
        if (fh->io->io_Actual)
            return true;
        else
            return fh->read_only;
    }
}


/*
 *  Check if the given file handle refers to a fixed or a removable disk
 */

bool SysIsFixedDisk(void *arg)
{
    file_handle *fh = (file_handle *)arg;
    if (!fh)
        return true;

    return true;
}


/*
 *  Check if a disk is inserted in the drive (always true for files)
 */

bool SysIsDiskInserted(void *arg)
{
    file_handle *fh = (file_handle *)arg;
    if (!fh)
        return false;

    if (fh->is_file)
        return true;
    else {

        // Check medium status
        fh->io->io_Command = TD_CHANGESTATE;
        fh->io->io_Actual = 0;
        DoIO((struct IORequest *)fh->io);
        bool inserted = (fh->io->io_Actual == 0);

        if (!inserted) {
            // Disk was ejected and has now been taken out
            fh->is_ejected = false;
        }

        if (fh->is_ejected) {
            // Disk was ejected but has not yet been taken out, report it as
            // no longer in the drive
            return false;
        } else
            return inserted;
    }
}


/*
 *  Prevent medium removal (if applicable)
 */

void SysPreventRemoval(void *arg)
{
    file_handle *fh = (file_handle *)arg;
    if (!fh)
        return;

    if (!fh->is_file) {

        // Send PREVENT ALLOW MEDIUM REMOVAL SCSI command
        struct SCSICmd scsi;
        static const UBYTE the_cmd[6] = {0x1e, 0, 0, 0, 1, 0};
        scsi.scsi_Length = 0;
        scsi.scsi_Command = (UBYTE *)the_cmd;
        scsi.scsi_CmdLength = 6;
        scsi.scsi_Flags = SCSIF_READ;
        scsi.scsi_Status = 0;
        fh->io->io_Data = &scsi;
        fh->io->io_Length = sizeof(scsi);
        fh->io->io_Command = HD_SCSICMD;
        DoIO((struct IORequest *)fh->io);
    }
}


/*
 *  Allow medium removal (if applicable)
 */

void SysAllowRemoval(void *arg)
{
    file_handle *fh = (file_handle *)arg;
    if (!fh)
        return;

    if (!fh->is_file) {

        // Send PREVENT ALLOW MEDIUM REMOVAL SCSI command
        struct SCSICmd scsi;
        static const UBYTE the_cmd[6] = {0x1e, 0, 0, 0, 0, 0};
        scsi.scsi_Length = 0;
        scsi.scsi_Command = (UBYTE *)the_cmd;
        scsi.scsi_CmdLength = 6;
        scsi.scsi_Flags = SCSIF_READ;
        scsi.scsi_Status = 0;
        fh->io->io_Data = &scsi;
        fh->io->io_Length = sizeof(scsi);
        fh->io->io_Command = HD_SCSICMD;
        DoIO((struct IORequest *)fh->io);
    }
}


/*
 *  Read CD-ROM TOC (binary MSF format, 804 bytes max.)
 */

bool SysCDReadTOC(void *arg, uint8 *toc)
{
    file_handle *fh = (file_handle *)arg;
    if (!fh)
        return false;

    if (fh->is_file)
        return false;
    else {

        // Send READ TOC MSF SCSI command
        struct SCSICmd scsi;
        static const UBYTE read_toc_cmd[10] = {0x43, 0x02, 0, 0, 0, 0, 0, 0x03, 0x24, 0};
        scsi.scsi_Data = (UWORD *)tmp_buf;
        scsi.scsi_Length = 804;
        scsi.scsi_Command = (UBYTE *)read_toc_cmd;
        scsi.scsi_CmdLength = 10;
        scsi.scsi_Flags = SCSIF_READ;
        scsi.scsi_Status = 0;
        fh->io->io_Data = &scsi;
        fh->io->io_Length = sizeof(scsi);
        fh->io->io_Command = HD_SCSICMD;
        if (DoIO((struct IORequest *)fh->io) || scsi.scsi_Status)
            return false;
        memcpy(toc, tmp_buf, 804);
        return true;
    }
}


/*
 *  Read CD-ROM position data (Sub-Q Channel, 16 bytes, see SCSI standard)
 */

bool SysCDGetPosition(void *arg, uint8 *pos)
{
    file_handle *fh = (file_handle *)arg;
    if (!fh)
        return false;

    if (fh->is_file)
        return false;
    else {

        // Send READ SUB-CHANNEL SCSI command
        struct SCSICmd scsi;
        static const UBYTE read_subq_cmd[10] = {0x42, 0x02, 0x40, 0x01, 0, 0, 0, 0, 0x10, 0};
        scsi.scsi_Data = (UWORD *)tmp_buf;
        scsi.scsi_Length = 16;
        scsi.scsi_Command = (UBYTE *)read_subq_cmd;
        scsi.scsi_CmdLength = 10;
        scsi.scsi_Flags = SCSIF_READ;
        scsi.scsi_Status = 0;
        fh->io->io_Data = &scsi;
        fh->io->io_Length = sizeof(scsi);
        fh->io->io_Command = HD_SCSICMD;
        if (DoIO((struct IORequest *)fh->io) || scsi.scsi_Status)
            return false;
        memcpy(pos, tmp_buf, 16);
        return true;
    }
}


/*
 *  Play CD audio
 */

bool SysCDPlay(void *arg, uint8 start_m, uint8 start_s, uint8 start_f, uint8 end_m, uint8 end_s, uint8 end_f)
{
    file_handle *fh = (file_handle *)arg;
    if (!fh)
        return false;

    if (fh->is_file)
        return false;
    else {

        // Send PLAY AUDIO MSF SCSI command
        struct SCSICmd scsi;
        UBYTE play_cmd[10] = {0x47, 0, 0, start_m, start_s, start_f, end_m, end_s, end_f, 0};
        scsi.scsi_Data = (UWORD *)tmp_buf;
        scsi.scsi_Length = 0;
        scsi.scsi_Command = play_cmd;
        scsi.scsi_CmdLength = 10;
        scsi.scsi_Flags = SCSIF_READ;
        scsi.scsi_Status = 0;
        fh->io->io_Data = &scsi;
        fh->io->io_Length = sizeof(scsi);
        fh->io->io_Command = HD_SCSICMD;
        if (DoIO((struct IORequest *)fh->io) || scsi.scsi_Status)
            return false;
        return true;
    }
}


/*
 *  Pause CD audio
 */

bool SysCDPause(void *arg)
{
    file_handle *fh = (file_handle *)arg;
    if (!fh)
        return false;

    if (fh->is_file)
        return false;
    else {

        // Send PAUSE RESUME SCSI command
        struct SCSICmd scsi;
        static const UBYTE pause_cmd[10] = {0x4b, 0, 0, 0, 0, 0, 0, 0, 0, 0};
        scsi.scsi_Data = (UWORD *)tmp_buf;
        scsi.scsi_Length = 0;
        scsi.scsi_Command = (UBYTE *)pause_cmd;
        scsi.scsi_CmdLength = 10;
        scsi.scsi_Flags = SCSIF_READ;
        scsi.scsi_Status = 0;
        fh->io->io_Data = &scsi;
        fh->io->io_Length = sizeof(scsi);
        fh->io->io_Command = HD_SCSICMD;
        if (DoIO((struct IORequest *)fh->io) || scsi.scsi_Status)
            return false;
        return true;
    }
}


/*
 *  Resume paused CD audio
 */

bool SysCDResume(void *arg)
{
    file_handle *fh = (file_handle *)arg;
    if (!fh)
        return false;

    if (fh->is_file)
        return false;
    else {

        // Send PAUSE RESUME SCSI command
        struct SCSICmd scsi;
        static const UBYTE resume_cmd[10] = {0x4b, 0, 0, 0, 0, 0, 0, 0, 1, 0};
        scsi.scsi_Data = (UWORD *)tmp_buf;
        scsi.scsi_Length = 0;
        scsi.scsi_Command = (UBYTE *)resume_cmd;
        scsi.scsi_CmdLength = 10;
        scsi.scsi_Flags = SCSIF_READ;
        scsi.scsi_Status = 0;
        fh->io->io_Data = &scsi;
        fh->io->io_Length = sizeof(scsi);
        fh->io->io_Command = HD_SCSICMD;
        if (DoIO((struct IORequest *)fh->io) || scsi.scsi_Status)
            return false;
        return true;
    }
}


/*
 *  Stop CD audio
 */

bool SysCDStop(void *arg, uint8 lead_out_m, uint8 lead_out_s, uint8 lead_out_f)
{
    file_handle *fh = (file_handle *)arg;
    if (!fh)
        return false;

    if (fh->is_file)
        return false;
    else {

        uint8 end_m = lead_out_m;
        uint8 end_s = lead_out_s;
        uint8 end_f = lead_out_f + 1;
        if (end_f >= 75) {
            end_f = 0;
            end_s++;
            if (end_s >= 60) {
                end_s = 0;
                end_m++;
            }
        }

        // Send PLAY AUDIO MSF SCSI command (play first frame of lead-out area)
        struct SCSICmd scsi;
        UBYTE play_cmd[10] = {0x47, 0, 0, lead_out_m, lead_out_s, lead_out_f, end_m, end_s, end_f, 0};
        scsi.scsi_Data = (UWORD *)tmp_buf;
        scsi.scsi_Length = 0;
        scsi.scsi_Command = play_cmd;
        scsi.scsi_CmdLength = 10;
        scsi.scsi_Flags = SCSIF_READ;
        scsi.scsi_Status = 0;
        fh->io->io_Data = &scsi;
        fh->io->io_Length = sizeof(scsi);
        fh->io->io_Command = HD_SCSICMD;
        if (DoIO((struct IORequest *)fh->io) || scsi.scsi_Status)
            return false;
        return true;
    }
}


/*
 *  Perform CD audio fast-forward/fast-reverse operation starting from specified address
 */

bool SysCDScan(void *arg, uint8 start_m, uint8 start_s, uint8 start_f, bool reverse)
{
    file_handle *fh = (file_handle *)arg;
    if (!fh)
        return false;

    //!!
    return false;
}


/*
 *  Set CD audio volume (0..255 each channel)
 */

void SysCDSetVolume(void *arg, uint8 left, uint8 right)
{
    file_handle *fh = (file_handle *)arg;
    if (!fh)
        return;

    if (!fh->is_file) {

        // Send MODE SENSE (CD-ROM Audio Control Parameters Page) SCSI command
        struct SCSICmd scsi;
        static const UBYTE mode_sense_cmd[6] = {0x1a, 0x08, 0x0e, 0, 20, 0};
        scsi.scsi_Data = (UWORD *)tmp_buf;
        scsi.scsi_Length = 20;
        scsi.scsi_Command = (UBYTE *)mode_sense_cmd;
        scsi.scsi_CmdLength = 6;
        scsi.scsi_Flags = SCSIF_READ;
        scsi.scsi_Status = 0;
        fh->io->io_Data = &scsi;
        fh->io->io_Length = sizeof(scsi);
        fh->io->io_Command = HD_SCSICMD;
        if (DoIO((struct IORequest *)fh->io) || scsi.scsi_Status)
            return;

        tmp_buf[6] = 0x04;        // Immed
        tmp_buf[9] = 0;            // LBA/sec format
        tmp_buf[10] = 0;        // LBA/sec
        tmp_buf[11] = 0;
        tmp_buf[13] = left;        // Port 0 volume
        tmp_buf[15] = right;    // Port 1 volume

        // Send MODE SELECT (CD-ROM Audio Control Parameters Page) SCSI command
        static const UBYTE mode_select_cmd[6] = {0x15, 0x10, 0, 0, 20, 0};
        scsi.scsi_Data = (UWORD *)tmp_buf;
        scsi.scsi_Length = 20;
        scsi.scsi_Command = (UBYTE *)mode_select_cmd;
        scsi.scsi_CmdLength = 6;
        scsi.scsi_Flags = SCSIF_WRITE;
        scsi.scsi_Status = 0;
        fh->io->io_Data = &scsi;
        fh->io->io_Length = sizeof(scsi);
        fh->io->io_Command = HD_SCSICMD;
        DoIO((struct IORequest *)fh->io);
    }
}


/*
 *  Get CD audio volume (0..255 each channel)
 */

void SysCDGetVolume(void *arg, uint8 &left, uint8 &right)
{
    file_handle *fh = (file_handle *)arg;
    if (!fh)
        return;

    if (!fh->is_file) {

        // Send MODE SENSE (CD-ROM Audio Control Parameters Page) SCSI command
        struct SCSICmd scsi;
        static const UBYTE mode_sense_cmd[6] = {0x1a, 0x08, 0x0e, 0, 20, 0};
        scsi.scsi_Data = (UWORD *)tmp_buf;
        scsi.scsi_Length = 20;
        scsi.scsi_Command = (UBYTE *)mode_sense_cmd;
        scsi.scsi_CmdLength = 6;
        scsi.scsi_Flags = SCSIF_READ;
        scsi.scsi_Status = 0;
        fh->io->io_Data = &scsi;
        fh->io->io_Length = sizeof(scsi);
        fh->io->io_Command = HD_SCSICMD;
        if (DoIO((struct IORequest *)fh->io) || scsi.scsi_Status)
            return;
        left = tmp_buf[13];        // Port 0 volume
        right = tmp_buf[15];    // Port 1 volume
    }
}