TABLE OF CONTENTS

WHDLoad/--Overview--
WHDLoad/resload_Abort
WHDLoad/resload_Control
WHDLoad/WHDLTAG_CBAF_SET
WHDLoad/WHDLTAG_CBSWITCH_SET
WHDLoad/WHDLTAG_IOERR_GET
WHDLoad/resload_CRC16
WHDLoad/resload_Decrunch
WHDLoad/resload_Delay
WHDLoad/resload_Delta
WHDLoad/resload_DeleteFile
WHDLoad/resload_DiskLoad
WHDLoad/resload_DiskLoadDev
WHDLoad/resload_Examine
WHDLoad/resload_ExNext
WHDLoad/resload_FlushCache
WHDLoad/resload_GetCustom
WHDLoad/resload_GetFileSize
WHDLoad/resload_GetFileSizeDec
WHDLoad/resload_ListFiles
WHDLoad/resload_LoadFile
WHDLoad/resload_LoadFileDecrunch
WHDLoad/resload_LoadFileOffset
WHDLoad/resload_LoadKick
WHDLoad/resload_Patch
WHDLoad/resload_PatchSeg
WHDLoad/resload_ProtectRead
WHDLoad/resload_ProtectReadWrite
WHDLoad/resload_ProtectRemove
WHDLoad/resload_ProtectSMC
WHDLoad/resload_ProtectWrite
WHDLoad/resload_Relocate
WHDLoad/resload_SaveFile
WHDLoad/resload_SaveFileOffset
WHDLoad/resload_SetCACR
WHDLoad/resload_SetCPU
WHDLoad.Slave/--Overview--


WHDLoad/--Overview--

The calling conventions for all functions are similar to the OS-Library
concept. Parameters are provided in registers (except for "resload_Abort"),
return codes come in D0 (on some functions also in D1). After a function call
the registers D0-D1/A0-A1 are destroyed (D0,D1 may contain a return code).
They are called scratch registers. All other registers are preserved. The base
of the JMP tower in WHDLoad is similar to a Library-Base. In difference to the
OS the base must not be loaded in A6 on calling a function, but it is
recommended to call all functions relative to a address register like:

        move.l  (_resload,pc),a5
        jsr     (resload_Decrunch,a5)

During the execution of resload functions interrupts are normally allowed. For
some internal operations they will be disabled for a short time. If the option
NoResInt/S is used the interrupts are disabled the whole time.

The resload functions will not use the registers A5 and A6 while interrupts are
allowed. Therefore interrupts of the installed program may assume that these
both registers contain previously set values. This is not true for all other
registers. If the interrupts assume constants in other registers (e.g. A4)
either the interrupt code must be patched accordingly or the interrupts must be
disabled before calling resload functions.

If option NoResInt/S is used all registers except D0/D1/A0/A1 remain unchanged
for interrupt code (but this option is for testing purposes only!).

The resload base is over given in A0 on calling the Slave first via
ws_GameLoader (see chapter WHDLoad.Slave/--Overview--).

All file names used with resload functions must be relative and must not
access any higher-level directories. That means file names must not start or
end with a slash ("/"), must not contain multiple slashes ("//") and must not
contain a colon (":"). These restrictions are enforced starting WHDLoad v16.9.
Earlier versions of WHDLoad will accept all names at the loss of being able to
preload them.

some keywords used in this document:

 Slave          file which contains the interface code
                (see section WHDLoad.Slave/--Overview--)

 BaseMem        the memory which is used by the installed program, because
                this memory is always Chip-memory and starts at address
                $00000000, BaseMem is at the same time the size and the end
                address of the used Chip-memory; BaseMem is specified in the
                Slave-structure in field "ws_BaseMemSize"

 ExpMem         is the expansions memory, a extra memory area which can
                optionally requested by the Slave-structure, it may be
                Chip- or Fast-memory dependently on what is available
                ExpMem is supported starting WHDLoad version 8

 Disk Image     a floppy disk stored as a file on hard disk

logical values used for return codes (see dos/dos.i):
 TRUE = -1 (or better <>0)
 FALSE = 0


WHDLoad/resload_Abort

   NAME
        resload_Abort -- quit and return to operating system

   SYNOPSIS
        resload_Abort( success, primary, secondary)
                         (a7)    (4,a7)    (8,a7)
                        ULONG    ULONG     ULONG

   FUNCTION
        This aborts and terminates the installed program and cause WHDLoad to
        return to the operating system.

   INPUTS
        success -   the reason for aborting
                    one of TDREASON_#? defined in the include file "whdload.i"
                    depending on this value WHDLoad continues different
                TDREASON_OK
                    a normal exit will performed
                TDREASON_DEBUG
                    WHDLoad will create dump files (.whdl_dump, .whdl_memory,
                    .whdl_register) and exit
                TDREASON_#? (except the above)
                    WHDLoad will show an requester which displays the reason
                    of aborting and requests the user to choose between
                    "Quit", "Restart" and "Make CoreDump"
        primary -   the primary return code further describing the reason of
                    aborting
                TDREASON_DELETEFILE, TDREASON_DISKLOAD, TDREASON_DISKLOADDEV,
                TDREASON_DOSLIST, TDREASON_DOSREAD, TDREASON_DOSWRITE
                    dos or trackdisk error code
                TDREASON_DEBUG
                    program counter (so it can by written to the dump files)
                TDREASON_OSEMUFAIL
                    name of the filed subsystem
                TDREASON_FAILMSG
                    message to display
                TDREASON_MUSTNTSC, TDREASON_MUSTPAL, TDREASON_MUSTREG,
                TDREASON_OK, TDREASON_REQ68020, TDREASON_REQAGA,
                TDREASON_WRONGVER
                    unused (can be omitted)
        secondary - the secondary return code further describing the reason of
                    aborting
                TDREASON_DELETEFILE, TDREASON_DOSREAD, TDREASON_DOSWRITE
                    filename
                TDREASON_DISKLOAD
                    disk number
                TDREASON_DOSLIST
                    name of directory scanned
                TDREASON_DEBUG
                    status register (so it can by written to the dump files)
                TDREASON_OSEMUFAIL
                    error number, depending on the primary return code
                TDREASON_DISKLOADDEV, TDREASON_FAILMSG, TDREASON_MUSTNTSC,
                TDREASON_MUSTPAL, TDREASON_MUSTREG, TDREASON_OK,
                TDREASON_REQ68020, TDREASON_REQAGA, TDREASON_WRONGVER
                    unused (can be omitted)

   EXAMPLE
        to simply quit:
                ...
                ; primary and secondary are not needed with TDREASON_OK
                move.l  #TDREASON_OK,-(a7)
                move.l  (_resload,pc),a0
                jmp     (resload_Abort,a0)

        to quit because reading of a file has failed:
                ...
                move.l  a0,-(a7)                        ;a0 = filename
                move.l  d0,-(a7)                        ;d0 = DOS error code
                move.l  #TDREASON_DOSREAD,-(a7)
                move.l  (_resload,pc),-(a7)
                add.l   #resload_Abort,(a7)
                rts

   RESULT
        nothing because WHDLoad will never return from this call

   BUGS

   NOTE
        This routine is the only one which must be called via JMP and not JSR
        because the parameters are located on the stack (that has the
        advantage that when aborting with TDREASON_DEBUG all registers can be
        preserved and written to the dump files by WHDLoad for later
        diagnostics)

   SEE ALSO
        example Slave sources provided with the WHDLoad developer package


WHDLoad/resload_Control

   NAME
        resload_Control

   SYNOPSIS
        success = resload_Control(tags)
          D0                       A0
         BOOL                    STRUCT

   FUNCTION
        control function of WHDLoad, allows to get and set various variables
        concerning the software and hardware configuration and to control the
        behavior of some WHDLoad operations

   INPUTS
        tags - pointer to a table of tag items

        the following items are currently supported:

        WHDLTAG_ATTNFLAGS_GET   - gets the AttnFlags describing the current
                                  CPU, FPU and MMU, the returned value is
                                  similar to execbase.AttnFlags but not equal
                                  because WHDLoad uses some additional bits,
                                  the Slave is only allowed to the use the
                                  defines from the standard include file
                                  "exec/execbase.i" for testing
        WHDLTAG_BUILD_GET       - gets WHDLoad build number
        WHDLTAG_BUTTONWAIT_GET  - returns -1 if WHDLoad option ButtonWait/S
                                  has been enabled, otherwise returns 0
        WHDLTAG_CBAF_SET        - sets a function which will be executed when
                                  an access fault exception occurs (see
                                  section WHDLoad/WHDLTAG_CBAF_SET for further
                                  informations)
        WHDLTAG_CBSWITCH_SET    - sets a function which will be executed when
                                  WHDLoad switches from the operating system
                                  to the installed program (see section
                                  WHDLoad/WHDLTAG_CBSWITCH_SET for further
                                  informations)
        WHDLTAG_CHKBLTHOG       - enables the 'dmacon.blthog' check, requires
                                  a active Snoop option and WHDLoad v13
        WHDLTAG_CHKBLTSIZE      - enables the 'blitter size' check, requires a
                                  active Snoop option and WHDLoad v13
        WHDLTAG_CHKBLTWAIT      - enables the 'blitter wait' check, requires a
                                  active Snoop option and WHDLoad v13
        WHDLTAG_CHKCOLBST       - enables the 'bplcon0.color' check, requires
                                  a active Snoop option and WHDLoad v13
        WHDLTAG_CHKCOPCON       - enables the 'copcon' check, requires
                                  a active Snoop option and WHDLoad v15.2
        WHDLTAG_CHIPREVBITS_GET - gets the ChipRevBits describing the current
                                  custom chips, see standard include file
                                  "graphics/gfxbase.i" for further infos
        WHDLTAG_CUSTOM1_GET
        WHDLTAG_CUSTOM2_GET
        WHDLTAG_CUSTOM3_GET
        WHDLTAG_CUSTOM4_GET
        WHDLTAG_CUSTOM5_GET     - returns numerical value of WHDLoad option
                                  Custom1/N .. Custom5/N
        WHDLTAG_DBGADR_SET      - sets a base address for debugging, this is
                                  only used for error messages by WHDLoad, on
                                  error it will additionally output the offset
                                  of the faulted address to this base, useful
                                  if you have program code somewhere (e.g. in
                                  ExpMem) and like to know at which offset in
                                  the program it has happen (without
                                  calculating it manually)
                                  requires WHDLoad v14.5
        WHDLTAG_DBGSEG_SET      - the same as WHDLTAG_DBGADR_SET but instead
                                  a memory address a BCPL pointer to a
                                  dos.library Segment is given, on error
                                  WHDLoad will display the offset in the
                                  relocated executable, like you would see
                                  it in a dis/reassembler
                                  requires WHDLoad v15.0
        WHDLTAG_ECLOCKFREQ_GET  - gets the EClockFrequency, which is the
                                  frequency the custom chips operate on, the
                                  value is taken from the execbase (see
                                  standard include file "exec/execbase.i")
        WHDLTAG_LANG_GET        - get language provided by lowlevel.library,
                                  see libraries/lowlevel.i for further infos,
                                  requires WHDLoad v13.2
        WHDLTAG_IOERR_GET       - gets the dos error code of a previously
                                  called resload function
        WHDLTAG_KEYTRANS_GET    - get pointer to a table for 'rawkey to ascii'
                                  conversion, the table has a length of 512
                                  bytes and contains 4 sub tables, first 128
                                  bytes representing the keys pressed without
                                  any modifier, then 128 bytes with Shift,
                                  then 128 bytes with Alt and last 128 Bytes
                                  with Shift and Alt
                                  the tables are created from the actual
                                  system keymap, dead keys are mapped like
                                  pressing Space afterwards, keys resulting in
                                  multibyte characters (F-Keys, Esc, ...) are
                                  set to 0 in the tables
        WHDLTAG_MONITOR_GET     - gets the used monitor/video mode, the
                                  returned value is one of NTSC_MONITOR_ID and
                                  PAL_MONITOR_ID (defined in the standard
                                  include file "graphics/modeid.i"), the
                                  WHDLoad options PAL/S and NTSC/S are
                                  affecting the monitor/video mode
        WHDLTAG_REVISION_GET    - gets WHDLoad minor version number
        WHDLTAG_TIME_GET        - gets current time and date, returned will be
                                  a pointer to a filled whdload_time structure
                                  which is described in the include file
                                  "whdload.i"
        WHDLTAG_VERSION_GET     - gets WHDLoad major version number

   EXAMPLE
        check if current CPU is at least an MC68020:
                ...
                clr.l   -(a7)                           ;TAG_DONE
                clr.l   -(a7)                           ;data to fill
                move.l  #WHDLTAG_ATTNFLAGS_GET,-(a7)
                move.l  a7,a0
                move.l  (_resload,pc),a2
                jsr     (resload_Control,a2)
                move.w  (6,a7),d0                       ;D0 = AttnFlags
                lea     (12,a7),a7                      ;restore sp
                btst    #AFB_68020,d0
                beq     .no68020
                ...
        get video mode and CPU:
                ...
                lea     (_tags,pc),a0
                move.l  (_resload,pc),a2
                jsr     (resload_Control,a2)
                move.l  (_mon,pc),d0                    ;D0 = video mode
                cmp.l   #NTSC_MONITOR_ID,d0
                beq     .ntsc
                ...

        _tags   dc.l    WHDLTAG_MONITOR_GET
        _mon    dc.l    0
                dc.l    WHDLTAG_ATTNFLAGS_GET
                dc.w    0                               ;padding
        _attn   dc.w    0
                dc.l    0                               ;TAG_DONE

   RESULT
        success is true if all items in the taglist has been successfully
        processed

   BUGS

   NOTE
        requires ws_Version >= 5

   SEE ALSO


WHDLoad/WHDLTAG_CBAF_SET

   NAME
        WHDLTAG_CBAF_SET

   SYNOPSIS
        to be used with resload_Control

        cont, adr,  data = CBAF(mode, size,  pc,  adr,  data/regs)
         D0    A1    A2          D0    D1    A0    A1    A2
        LONG  APTR  APTR        LONG  LONG  APTR  APTR  APTR

   FUNCTION
        Using this tag a function can be set which will executed when an
        access fault exception occurs which is not handled by WHDLoad itself.
        It may be used to locate specific accesses in conjunction with
        resload_Protect and to walk around invalid accesses during the
        development process.
        on the 68030 all access faults can be caught except:
         - instruction stream faults
         - faults caused by WHDLoad's blitwait and blitsize checks
        on the 68040/60 only these access faults can be caught:
         - faults caused by resload_Protect
        The routine being set must not change any registers except the ones
        holding a return value. The routine must return via RTS. On entering
        the routine all interrupts are disabled (sr=$27xx).

   INPUTS
        mode - transfer mode of the faulted access
                0 - read
                1 - modify (only 68060)
                2 - write
        size - operand size of the attempted access
                1 - Byte
                2 - Word
                4 - LongWord
        pc   - program counter of the instruction which has faulted
               (warning: on the 68040/60 this sometimes points the instruction
               after the one which has faulted, read the appropriate
               microprocessor user manual for further informations)
        adr  - the address which has been attempted to access
        data - on the 68030 valid only on write operations, the given memory
               address contains the data which has been tried to write
               on the 68040/60 it contains a pointer to memory where the
               registers D0-A6 are stored

   RESULT
        cont - how to continue
                0 - terminate, WHDLoad will show a requester notifying the
                    access fault
                1 - proceed, the faulted access will be emulated by the
                    handler inside WHDLoad
        adr  - only on 68030: in case of cont=proceed the address which will be
               accessed
        data - only on 68030: in case of cont=proceed and mode=write a pointer
               to the data which will be written

   EXAMPLE
        If you want to get informed at which point the installed program
        writes the value 42 to the address $BABE use the following code:
                ...
                clr.l   -(a7)                           ;TAG_DONE
                pea     (_af,pc)                        ;function
                move.l  #WHDLTAG_CBAF_SET,-(a7)
                move.l  a7,a0
                move.l  (_resload,pc),a2
                jsr     (resload_Control,a2)
                lea     (12,a7),a7                      ;restore sp
                moveq   #2,d0
                lea     ($BABE),a0
                jsr     (resload_ProtectWrite,a2)       ;protect area
                ...

     _af        cmp.l   #$BABE,a1                       ;correct address ?
                bne     .term
                cmp.w   #2,d1                           ;size
                bne     .term
                cmp.w   #42,(a2)                        ;a2 is only valid on
                                                        ;68030!
                beq     .term
                moveq   #1,d0                           ;proceed
                rts

    .term       moveq   #0,d0                           ;terminate
                rts

   EXAMPLE
        If want you to redirect an access to $24 to the address $300, use the
        following code (works only on 68030!):
                ...
                clr.l   -(a7)                           ;TAG_DONE
                pea     (_af,pc)                        ;function
                move.l  #WHDLTAG_CBAF_SET,-(a7)
                move.l  a7,a0
                move.l  (_resload,pc),a2
                jsr     (resload_Control,a2)
                lea     (12,a7),a7                      ;restore sp
                moveq   #4,d0
                lea     ($24),a0
                jsr     (resload_ProtectWrite,a2)       ;protect area
                ...

     _af        cmp.l   #$24,a1                         ;correct address ?
                bne     .term
                lea     ($300),a1
                moveq   #1,d0                           ;proceed
                rts

    .term       moveq   #0,d0                           ;terminate
                rts


   BUGS
        fully supported is only the 68030, limited support for 68040/60

   NOTE
        requires ws_Version >= 9
        on the 68040 it's supported starting WHDLoad 17.0
        on the 68060 it's supported starting WHDLoad 16.1
        the parameter a2=regs on the 68060 is supported since WHDLoad 16.4
        MUST not be used in public releases, use it during development process
        only

   SEE ALSO
        resload_Control


WHDLoad/WHDLTAG_CBSWITCH_SET

   NAME
        WHDLTAG_CBSWITCH_SET

   SYNOPSIS
        to be used with resload_Control

        CBSWITCH()

   FUNCTION
        Using this tag a routine can be set which will executed each time
        WHDLoad switches from the operating system to the installed program.
        Such a routine is sometimes necessary because during the switch
        between the installed program and the operating system some hardware
        registers are modified by the operating system.
        Known registers getting modified are cop2lc, bltafwm and bltalwm (maybe
        there are more of them).
        The routine must not change any registers, must not use any stack and
        has to return via "jmp (a0)". At execution time of the routine all
        interrupts and DMAs are disabled and the memory setup of the installed
        program is active.

   INPUTS
        pointer to the routine to execute during switch, a value equal 0
        disables the execution of a routine

   EXAMPLE
                ...
                clr.l   -(a7)                           ;TAG_DONE
                pea     (_cbswitch,pc)                  ;function
                move.l  #WHDLTAG_CBSWITCH_SET,-(a7)
                move.l  a7,a0
                move.l  (_resload,pc),a2
                jsr     (resload_Control,a2)
                lea     (12,a7),a7                      ;restore sp
                ...

     _cbswitch  move.l  (_c2,pc),(_custom+cop2lc)
                jmp     (a0)

     _cb2       dc.l    $10e80

   RESULT
        none

   BUGS

   NOTE
        requires ws_Version >= 7

   SEE ALSO
        resload_Control


WHDLoad/WHDLTAG_IOERR_GET

   NAME
        WHDLTAG_IOERR_GET

   SYNOPSIS
        to be used with resload_Control

   FUNCTION
        This tag can be used to get the DOS error code of the last called
        resload function. All resload functions except resload_Control will
        set/reset this error code.
        Two resload functions are special in that way:
            resload_GetFileSize
                If a file with the specified name cannot be opened via
                dos.Open, the error code will be set to the value returned
                from dos.IoErr. So the error code may contain values like
                ERROR_OBJECT_NOT_FOUND, ERROR_OBJECT_WRONG_TYPE,
                ERROR_READ_PROTECTED or similar (see NDK include file
                dos/dos.i). The error code can be used to distinguish between
                a file with the size of 0 and a nonexistent file.
            resload_ListFiles
                If the specified buffer to fill is not large enough to hold
                all file names from the scanned directory, the error code will
                be set to ERROR_NO_FREE_STORE.

   INPUTS
        none

   EXAMPLE
                ...
                clr.l   -(a7)                           ;TAG_DONE
                clr.l   -(a7)                           ;data to fill
                move.l  #WHDLTAG_IOERR_GET,-(a7)
                move.l  a7,a0
                move.l  (_resload,pc),a2
                jsr     (resload_Control,a2)
                move.l  (4,a7),d0                       ;D0 = IoErr
                lea     (12,a7),a7                      ;restore sp
                ...

   RESULT
        none

   BUGS

   NOTE
        requires ws_Version >= 8

   SEE ALSO
        resload_Control, resload_GetFileSize, resload_ListFiles


WHDLoad/resload_CRC16

   NAME
        resload_CRC16 -- calculate ANSI conform 16 bit CRC checksum

   SYNOPSIS
        checksum = resload_CRC16(length,address)
           D0                      D0     A0
         UWORD                   ULONG   APTR

   FUNCTION
        calculate ANSI conform 16 bit CRC checksum
        mostly used to difference between various program/data versions

   INPUTS
        length  - length of area to calculate over
        address - pointer to area

   EXAMPLE
                ...
                lea     $1000,a0                ;at address $1000
                move.l  #256,d0                 ;up to address $1100
                move.l  (_resload,pc),a2
                jsr     (resload_CRC16,a2)
                cmp.w   #$f2b7,d0
                bne     .false_version
                ...

   RESULT
        checksum - 16 bit CRC

   BUGS

   NOTE
        requires ws_Version >= 3

   SEE ALSO


WHDLoad/resload_Decrunch

   NAME
        resload_Decrunch -- uncompress data in memory

   SYNOPSIS
        size = resload_Decrunch(source, destination)
         D0                       A0        A1
        ULONG                    APTR      APTR

   FUNCTION
        This unpacks compressed data in memory. Known compressed data formats
        are RNC1, RNC2, IMP!, ATN!, TPWM and Cr[Mm][!2].
        If the data source doesn't point to a known compressed format size=0
        will be returned. Else the data will be unpacked to the destination
        and the size of the decompressed data is returned.
        Source and destination can be equal. In that case the packed data will
        be overwritten.

        RNC1:   Rob Northen compressor - emphasis on packed size
                Supported is the old and the new format. Both formats using the
                same id but different file formats and compressing algorithms.
                The function uses some heuristic checks to determine the
                correct format. The decompressor for the new common format is
                highly optimized and contains a separate routine for 68000/10
                and one for 68020+. On 68060 it's faster than the Imploder
                decompressor.
        RNC2:   Rob Northen compressor - emphasis on unpacking speed
                It's the fastest supported decompressor.
        IMP!:   Imploder (FImp)
                The packed data data must not overlap the destination. The
                destination must be either equal the source or outside the
                source data. In difference to the original explode routine
                resload_Decrunch does not destroy the source data (if source
                is not equal destination).
        ATN!:   identical to IMP! only id is different
        TPWM:   Turbo Packer Wolfgang Mayerle
                Supported starting WHDLoad v11. Because the file header does
                not contain the length of the packed data there is no
                integrity check performed.
        Cr[Mm][!2]: Crunch-Mania by Thomas Schwarz
                Supported starting WHDLoad v17. The packed source data must be
                located on a word aligned address for 68000/10 compatibility!

        All decompression routines have been modified to not modify the
        registers A5 and A6 and to use nearly no stack space.
        All decompression routines are performing a check if the decompression
        was successful. On a failure the installed program will be terminated
        and WHDLoad will display a message telling this.

   INPUTS
        source      - address of source in memory
        destination - address of destination in memory (can be equal to source)

   EXAMPLE

   RESULT
        size - the size of the uncompressed data or 0 if is not compressed
               with a known format

   BUGS

   NOTE
        the routine performs automatically a resload_FlushCache before
        returning

   SEE ALSO
        resload_LoadFileDecrunch


WHDLoad/resload_Delay

   NAME
        resload_Delay -- wait some time or user action

   SYNOPSIS
        resload_Delay(time)
                       D0
                      ULONG

   FUNCTION
        Wait the specified time or until a button/key is pressed. All possible
        buttons (LMB, MMB, RMB) of both controllers (port 0/1) and the keyboard
        is checked. After the time runs out or something has been pressed the
        function waits until the pressed controller button has been released.
        But it does not wait for a keyboard key up.
        The wait routine is based on the raster beam. But checks the current
        display and therefore waits the correct time on PAL and NTSC displays.

   INPUTS
        time - time to wait in 1/10 seconds

   EXAMPLE
                ...
                moveq   #30,d0                  ;3 seconds
                move.l  (_resload,pc),a2
                jsr     (resload_Delay,a2)
                ...

   RESULT
        nothing, all registers are preserved

   BUGS

   NOTE
        in difference to most others resload_#? function this routine is
        granted to preserve all registers
        requires ws_Version >= 8

   SEE ALSO


WHDLoad/resload_DeleteFile

   NAME
        resload_Delete -- delete file/directory

   SYNOPSIS
        success,errorcode = resload_DeleteFile(name)
          D0       D1                           A0
         BOOL    ULONG                         CPTR

   FUNCTION
        This deletes the file or directory with the specified name.
        A directory must be empty for deletion.
        If there are multiple data directories used the object to delete
        must be located in the first data directory. Otherwise deleting
        will fail with a DOS error code ERROR_OBJECT_NOT_FOUND.

   INPUTS
        name - name of the file/directory to delete

   EXAMPLE
                ...
                lea     (_name,pc),a0
                move.l  (_resload,pc),a2
                jsr     (resload_DeleteFile,a2)
                ...

        _name   dc.b    "C/WHDLoad",0

   RESULT
        success   - TRUE on success
        errorcode - 0 on success
                    otherwise a DOS error code from dos.IoErr()
        if WHDLF_NoError is set, the function only returns on success

   BUGS

   NOTE
        requires ws_Version >= 8

   SEE ALSO


WHDLoad/resload_Delta

   NAME
        resload_Delta -- apply WDelta file

   SYNOPSIS
        resload_Delta(src,  dest, delta)
                       A0    A1    A2
                      APTR  APTR  APTR

   FUNCTION
        Applies the differences provided via the delta data onto the source
        data and creates the destination data.
        WDelta is a tool to calculate a binary differences file from two data
        files (like scompare/spatch). It can be found on aminet
        (http://main.aminet.net/util/cli/WDelta.lha).
        This function can be used to support different versions of data or
        program files by converting them into one single version.

   INPUTS
        src   - source data
        dest  - destination memory
        delta - wdelta data

   EXAMPLE
                ...
                lea     ($10000),a0             ;source
                lea     ($400),a1               ;destination
                lea     ($40000),a2             ;wdelta
                move.l  (_resload,pc),a3
                jsr     (resload_Delta,a3)
                ...

   RESULT

   BUGS

   NOTE
        The source and the destination will be CRC checked.
        If an error occurs WHDLoad will quit with an appropriate requester.
        requires ws_Version >= 11

   SEE ALSO


WHDLoad/resload_DiskLoad

   NAME
        resload_DiskLoad -- load part from a disk image

   SYNOPSIS
        success,errorcode = resload_DiskLoad(offset,size,diskno,dest)
          D0       D1                          D0    D1    D2    A0
         BOOL    ULONG                        ULONG ULONG UBYTE APTR

   FUNCTION
        Loads part from a disk image as specified by the parameters.
        The name of the disk images is expected as 'disk.' followed by the
        number of the disk (e.g. 'Disk.1').
        The size of the disk images is variable. An attempt to read data
        outside of the disk image will result in a DOS error
        ERROR_SEEK_ERROR.

   INPUTS
        offset - offset in disk image (relative to the beginning)
        size   - amount of bytes to read
        diskno - disk number
        dest   - destination address

   EXAMPLE
                ...
                move.l  #880*512,d0             ;from block 880
                move.l  #2*512,d1               ;2 blocks
                moveq   #1,d2                   ;disk 1
                lea     $80000,a0               ;destination
                move.l  (_resload,pc),a2
                jsr     (resload_LoadDisk,a2)
                ...

   RESULT
        success   - TRUE on success
        errorcode - 0 on success
                    otherwise a DOS error code from dos.IoErr()
        if WHDLF_NoError is set, the function only returns on success

   BUGS

   NOTE
        The routine performs automatically a resload_FlushCache before
        returning.

   SEE ALSO
        resload_LoadFileOffset


WHDLoad/resload_DiskLoadDev

   NAME
        resload_DiskLoadDev -- load part from a floppy disk

   SYNOPSIS
        success,errorcode = resload_DiskLoadDev(offset, size,  dest,  tags)
          D0        D1                            D0     D1     A0     A1
         BOOL     ULONG                         ULONG  ULONG  UBYTE  STRUCT

   FUNCTION
        Loads a given amount of data from a floppy device.

   INPUTS
        offset - offset on the disk (must be a multiple of 512 bytes)
        size   - amount of bytes to read (must be a multiple of 512 bytes)
        dest   - destination address (must be aligned to 512 bytes)
        tags   - pointer to a taglist, starting WHDLoad version 16.0
                 there is one supported tag WHDLTAG_TDUNIT which
                 specifies the trackdisk.device unit to read from, default
                 is unit 0 (DF0:)

   EXAMPLE
                ...
                move.l  #880*512,d0             ;from block 880
                move.l  #2*512,d1               ;2 blocks
                lea     $80000,a0               ;destination
                sub.l   a1,a1                   ;tag list
                move.l  (_resload,pc),a2
                jsr     (resload_LoadDisk,a2)
                ...

   RESULT
        success   - TRUE on success
        errorcode - 0 on success
                    otherwise a trackdisk error code
        if WHDLF_NoError is set, the function only returns on success

   BUGS

   NOTE
        requires ws_Version >= 2
        At the moment all parameters (offset, size, address) must be aligned
        to 512 bytes due restrictions of trackdisk.device.
        The routine performs automatically a resload_FlushCache before
        returning.

   SEE ALSO


WHDLoad/resload_Examine

   NAME
        resload_Examine -- get informations about a file or directory

   SYNOPSIS
        success,errorcode = resload_Examine(name, FileInfoBlock)
          D0        D1                       A0         A1
         BOOL     ULONG                     CPTR       APTR

   FUNCTION
        Fills the supplied FileInfoBlock with informations about the
        specified file or directory. See NDK include file dos/dos.i for the
        structure of the FileInfoBlock.

   INPUTS
        name - name of the object to get info about
        fib  - store pool of 260 bytes for the infos

   EXAMPLE
                ...
                lea     (_filename,pc),a0
                sub.l   #fib_SIZEOF,a7
                move.l  a7,a1
                move.l  (_resload,pc),a2
                jsr     (resload_Examine,a2)
                ...
                add.l   #fib_SIZEOF,a7
                ...

   RESULT
        success - is true (-1) on success and false (0) on failure
        errorcode - contains DOS error code (e.g. ERROR_OBJECT_NOT_FOUND)

   BUGS
        Relative path names (starting/ending with '/' or containing '//') are
        not supported. The name must also not contain a ':'.
        The fib_Size will be incorrect if the file is more than two times
        compressed using XPK or compressed using XPK and afterwards encrypted
        using XPK.

   NOTE
        requires ws_Version >= 15

   SEE ALSO
        resload_GetFileSize, resload_GetFileSizeDec, resload_ExNext


WHDLoad/resload_ExNext

   NAME
        resload_ExNext -- get informations about next directory entry

   SYNOPSIS
        success,errorcode = resload_Examine(FileInfoBlock)
          D0        D1                          A0
         BOOL     ULONG                        APTR

   FUNCTION
        Fills the supplied FileInfoBlock with informations about the next
        directory entry. The FileInfoBlock must be previously initialized by
        a call to resload_Examine.

   INPUTS
        fib - store pool of 260 bytes for the infos

   EXAMPLE
                ...
                lea     (_dirname,pc),a0
                sub.l   #fib_SIZEOF,a7
                move.l  a7,a1
                move.l  (_resload,pc),a2
                jsr     (resload_Examine,a2)
                tst.l   d0
                beq     .end
   .next        move.l  a7,a0
                jsr     (resload_ExNext,a2)
                tst.l   d0
                beq     .end
                ...
                bra     .next
   .end         add.l   #fib_SIZEOF,a7
                ...

   RESULT
        success - is true (-1) on success and false (0) on failure
        errorcode - if there are no more entries left it contains
        ERROR_NO_MORE_ENTRIES

   BUGS
        The fib_Size will be incorrect if the file is more than two times
        compressed using XPK or compressed using XPK and afterwards encrypted
        using XPK.

   NOTE
        requires ws_Version >= 15

   SEE ALSO
        resload_Examine


WHDLoad/resload_FlushCache

   NAME
        resload_FlushCache -- clear CPU caches

   SYNOPSIS
        resload_FlushCache()

   FUNCTION
        clears all CPU caches

   INPUTS

   EXAMPLE

   RESULT

   BUGS

   NOTE
        In difference to most other resload_#? functions this routine is
        granted to preserve all registers.
        It's safe to call this routine from User and Supervisor mode and
        independent of the actual CPU type (also on 68000/010).
        It uses the CACR on 68020/30 and a "cpusha bc" on 68040/60.

   SEE ALSO
        resload_SetCPU


WHDLoad/resload_GetCustom

   NAME
        resload_GetCustom -- get Custom argument

   SYNOPSIS
        success = resload_GetCustom(buflen, reserved, buffer)
          D0                          D0       D1       A0
         ULONG                       ULONG    ULONG    CPTR

   FUNCTION
        Get the string which has been specified via the Custom/S option.
        The buffer is filled as far as possible. If buffer was not large
        enough false will be returned.

   INPUTS
        buflen   - size of buffer
        reserved - currently not used, must be set to 0
        buffer   - memory area to fill

   EXAMPLE
                ...
                move.l  #$100,d0
                moveq   #0,d1
                lea     ($1000),a0
                move.l  (_resload,pc),a2
                jsr     (resload_GetCustom,a2)
                tst.l   d0
                beq     .error
                ...

   RESULT
        success - zero if buffer was too small

   BUGS

   NOTE
        requires ws_Version >= 15

   SEE ALSO


WHDLoad/resload_GetFileSize

   NAME
        resload_GetFileSize -- get size of a file

   SYNOPSIS
        size = resload_GetFileSize(name)
         D0                         A0
        ULONG                      CPTR

   FUNCTION
        Gets size of a file (check if a file exists).
        To distinguish between a file with a size of 0 and a nonexistent
        file the tag WHDLTAG_IOERR_GET must be used in conjunction with
        resload_Control afterwards.

   INPUTS
        name - name of the file to get the size of

   EXAMPLE
                ...
                lea     (_filename,pc),a0
                move.l  (_resload,pc),a2
                jsr     (resload_GetFileSize,a2)
                tst.l   d0
                bne     .file_exist
                clr.l   -(a7)                           ;TAG_DONE
                clr.l   -(a7)                           ;data to fill
                move.l  #WHDLTAG_IOERR_GET,-(a7)
                move.l  a7,a0
                jsr     (resload_Control,a2)
                move.l  (4,a7),d0
                lea     (12,a7),a7                      ;restore sp
                beq     .file_exist
                ...

   RESULT
        size - the size of the file, 0 if does not exist

   BUGS

   NOTE
        This routine returns the file size obtained from the filesystem. If the
        file is compressed and is loaded later via resload_LoadFileDecrunch the
        loaded file size will differ!

   SEE ALSO
        resload_Control, resload_GetFileSizeDec, resload_LoadFile,
        resload_LoadFileDecrunch


WHDLoad/resload_GetFileSizeDec

   NAME
        resload_GetFileSizeDec -- get size of a packed file

   SYNOPSIS
        size = resload_GetFileSizeDec (name)
         D0                         A0
        ULONG                      CPTR

   FUNCTION
        Gets size of a packed file (check if a file exists).
        The routine knows about the same decrunchers as resload_Decrunch.
        To distinguish between a file with a size of 0 and a nonexistent
        file the tag WHDLTAG_IOERR_GET must be used in conjunction with
        resload_Control afterwards.

   INPUTS
        name - name of the file to get the size of

   EXAMPLE
                ...
                lea     (_filename,pc),a0
                move.l  (_resload,pc),a2
                jsr     (resload_GetFileSizeDec,a2)
                tst.l   d0
                beq     .file_not_exist
                ...

   RESULT
        size - the size of the file, 0 if does not exist

   BUGS

   NOTE
        requires ws_Version >= 11

   SEE ALSO
        resload_Control, resload_GetFileSize, resload_LoadFile,
        resload_LoadFileDecrunch


WHDLoad/resload_ListFiles

   NAME
        resload_ListFiles -- list filenames of a directory

   SYNOPSIS
        amount,errorcode = resload_ListFiles(buffersize, name, buffer)
          D0      D1                             D0       A0     A1
        ULONG   ULONG                          ULONG     CPTR   APTR

   FUNCTION
        Writes the names of all files in the specified directory to the
        buffer. The file names are separated with a 0 character.
        Only files are listed, directories are skipped.
        If the buffer to fill is not large enough to hold all names the
        routine fills it as far as possible. The tag WHDLTAG_IOERR_GET in
        conjunction with resload_Control can be used afterwards to check if
        all file names have fit into the buffer.
        If multiple data directories are used, only the first data directory
        will be scanned.

   INPUTS
        buffersize - the size of the buffer
        name       - the name of the directory to scan
        buffer     - pointer to the buffer to fill (up to WHDLoad v16.8 the
                     buffer must be located inside the Slave, from WHDLoad
                     v16.9 on it can also be located in ExpMem)

   EXAMPLE
                ...
                move.l  #_bufend-_buf,d0
                lea     (_savepath,pc),a0
                lea     (_buf,pc),a1
                move.l  (_resload,pc),a2
                jsr     (resload_ListFiles,a2)
                ...

        _buf      ds.b    1000
        _bufend
        _savepath dc.b  "save",0


   RESULT
        amount    - amount of listed files in the buffer
        errorcode - 0 on success
                    otherwise a DOS error code from dos.IoErr()
        if WHDLF_NoError is set, the function only returns on success

   BUGS

   NOTE
        A call to this resload function always causes a switch to the
        operating system because the informations to provide are not
        cached. To avoid this switch resload_Examine and resload_ExNext
        can be used (but will require some additional memory for the
        Directory PreLoad).

   SEE ALSO
        resload_Control


WHDLoad/resload_LoadFile

   NAME
        resload_LoadFile -- load file into memory

   SYNOPSIS
        length,errorcode = resload_LoadFile(name, address)
          D0      D1                         A0      A1
        ULONG    ULONG                      CPTR    APTR

   FUNCTION
        Loads the file to the specified memory address.

   INPUTS
        name    - name of the file to load
        address - memory address to load the file on

   EXAMPLE
                ...
                lea     (_filename),a0          ;name
                lea     $1000.w,a1              ;destination
                move.l  (_resload,pc),a2
                jsr     (resload_LoadFile,a2)
                ...

   RESULT
        length    - the size of the loaded file, or 0 on error
        errorcode - 0 on success
                    otherwise a DOS error code from dos.IoErr()
        if WHDLF_NoError is set, the function only returns on success

   BUGS

   NOTE
        The routine performs automatically a resload_FlushCache before
        returning.

   SEE ALSO
        resload_LoadFileDecrunch, resload_LoadFileOffset


WHDLoad/resload_LoadFileDecrunch

   NAME
        resload_LoadFileDecrunch -- load file and uncompress

   SYNOPSIS
        length,errorcode = resload_LoadFileDecrunch(name, address)
          D0      D1                                 A0      A1
        ULONG    ULONG                              CPTR    APTR

   FUNCTION
        Loads the specified file into memory and unpack it if compressed in a
        supported format. Supported are the same formats as with
        resload_Decrunch.
        Using this routine instead of resload_LoadFile easily allows it to add
        support for compressed data files to a installed program. Because of
        the transparent decompression the installed program will not notify if
        the files loaded were compressed on disk or not. The only thing which
        must be considered is that files which are written using
        resload_SaveFileOffset or loaded via resload_LoadFileOffset must not
        be compressed.

   INPUTS
        name    - name of file to load
        address - memory address to load the file on

   EXAMPLE
                ...
                lea     (_filename),a0          ;name
                lea     $1000.w,a1              ;destination
                move.l  (_resload,pc),a2
                jsr     (resload_LoadFileDecrunch,a2)
                ...

   RESULT
        length    - the size of the loaded file
                    if an error occurs this is 0
        errorcode - 0 on success
                    otherwise a DOS error code from dos.IoErr()
        if WHDLF_NoError is set, the function only returns on success

   BUGS

   NOTE
        The routine performs automatically a resload_FlushCache before
        returning.

   SEE ALSO
        resload_Decrunch, resload_LoadFile, resload_LoadFileOffset,
        resload_SaveFile, resload_SaveFileOffset


WHDLoad/resload_LoadFileOffset

   NAME
        resload_LoadFileOffset -- load data from inside a file to memory

   SYNOPSIS
        success,error = resload_LoadFileOffset(size, offset, name, address)
          D0     D1                             D0     D1     A0      A1
         BOOL   ULONG                          ULONG  ULONG  CPTR    APTR

   FUNCTION
        Loads a part of a file into memory. The part of the file is specified
        by an offset in the file and a byte count to read. The routine is
        nearly identical to resload_DiskLoad but instead of specifying the
        number of the disk to read from a filename is used to select the file.

   INPUTS
        size    - amount of bytes to read
        offset  - offset in the file
        name    - name of file
        address - memory address to load the file on

   EXAMPLE
                ...
                move.l  #512,d0                 ;size
                move.l  #$4000,d1               ;offset
                lea     (_save,pc),a0           ;name
                lea     $5ac20,a1               ;source
                move.l  (_resload,pc),a2
                jsr     (resload_LoadFileOffset,a2)
                ...

        _save   dc.b    "saved",0

   RESULT
        success   - TRUE on success
        errorcode - 0 on success
                    otherwise a DOS error code from dos.IoErr()
        if WHDLF_NoError is set, the function only returns on success

   BUGS

   NOTE
        The routine performs automatically a resload_FlushCache before
        returning.
        requires ws_Version >= 6

   SEE ALSO
        resload_DiskLoad, resload_LoadFile


WHDLoad/resload_LoadKick

   NAME
        resload_LoadKick -- load Kickstart image

   SYNOPSIS
        resload_LoadKick(size, crc16,  name)
                          D0     D1     A0
                         ULONG  UWORD  CPTR

   FUNCTION
        Loads the Kickstart image with the specified name into ExpMem.

   INPUTS
        size    - size of Kickstart image
        crc16   - CRC16 of Kickstart image
        name    - base name of Kickstart image

   EXAMPLE
                ...
                move.l  #$40000,d0              ;size
                move.w  #$f20b,d1               ;crc16
                lea     (_kick,pc),a0           ;name
                move.l  (_resload,pc),a2
                jsr     (resload_LoadKick,a2)
                ...

        _kick   dc.b    "34005.a500",0

   RESULT

   BUGS

   NOTE
        requires ws_Version >= 11
        This function is depreciated since WHDLoad v16 because loading a
        Kickstart this way will cause a switch to the operation system.
        Starting with WHDLoad v16 the Kickstart image to load can be
        specified in the Slave structure and when used WHDLoad will load it
        before the Slave will called.

   SEE ALSO


WHDLoad/resload_Patch

   NAME
        resload_Patch -- apply patch list

   SYNOPSIS
        resload_Patch(patchlist, destination)
                         A0          A1
                        APTR        APTR

   FUNCTION
        Modify memory using commands from a specified patch list.
        To make an installed program work under WHDLoad it must be patched.
        That means the program must be modified so that it will load data via
        WHDLoad instead of using its own loader routines. Often also various
        other things must be changed to make it working.
        The modifying of the installed program can be done using this routine.
        A patch list will be build using macros from the include file
        'whdload.i'. Each entry in the patch list contains a command to
        perform, an address to apply the command on and optional extra data.
        resload_Patch is especially useful if the memory to modify is located
        in ExpMem and therefore the destination address in only known at
        runtime and not at creation time of the Slave.

   INPUTS
        patchlist   - list of commands describing the patches to apply
        destination - address of memory region to patch

   EXAMPLE
                ...
                lea     (_pl,pc),a0             ;patch list
                move.l  (_expmem,pc),a1         ;destination
                move.l  (_resload,pc),a2
                jsr     (resload_Patch,a2)
                ...

        _pl     PL_START
                PL_P    $560,_loadfile          ;the loading routine
                PL_R    $2046                   ;copylock
                PL_END

   RESULT

   BUGS

   NOTE
        The routine performs automatically a resload_FlushCache before
        returning.
        requires ws_Version >= 10

   SEE ALSO
        resload_PatchSeg


WHDLoad/resload_PatchSeg

   NAME
        resload_PatchSeg -- apply patch list to a segment list

   SYNOPSIS
        resload_PatchSeg(patchlist, seglist)
                           A0          A1
                          APTR        BPTR

   FUNCTION
        This function is similar to resload_Patch. But instead of patching
        memory at a specific address a segment list is used. A segment list is
        list of linked list memory regions and returned by dos.LoadSeg or
        resload_Relocate.

   INPUTS
        patchlist - list of commands describing the patches to apply
        seglist   - list of segments as returned by dos.LoadSeg or
                    resload_Relocate (that is a BCPL pointer!)

   EXAMPLE
                ...
                lea     (_name,pc),a0
                move.l  a0,d1                   ;filename
                move.l  (_dosbase,pc),a6
                jsr     (_LVOLoadSeg,a6)
                lea     (_pl,pc),a0             ;patch list
                move.l  d1,a1                   ;segment list
                move.l  (_resload,pc),a2
                jsr     (resload_PatchSeg,a2)
                ...

        _pl     PL_START
                PL_P    $560,_loadfile          ;the loading routine
                PL_R    $2046                   ;copylock
                PL_END
        _name   dc.b    "program",0

   RESULT

   BUGS

   NOTE
        The routine performs automatically a resload_FlushCache before
        returning.
        requires ws_Version >= 15

   SEE ALSO
        resload_Patch


WHDLoad/resload_ProtectRead

   NAME
        resload_ProtectRead -- mark memory as read protected

   SYNOPSIS
        resload_ProtectRead(length, address)
                              D0      A0
                             ULONG   APTR

   FUNCTION
        Protects the specified memory against reading by the processor.
        The memory to protect must be located inside BaseMem or ExpMem.

   INPUTS
        length  - size of the memory area to protect
        address - start address of the memory area to protect

   EXAMPLE
                ...
                moveq   #4,d0                   ;one longword
                lea     $4070,a0                ;address
                move.l  (_resload,pc),a2
                jsr     (resload_ProtectRead,a2)
                ...

   RESULT
        a "Exception 'Access Fault'" WHDLoad requester if the protected memory
        is read

   BUGS
        The amount of protected areas is currently limited to 16.
        The page where the SSP points to must not be protected. Because if a
        Access Fault occurs the CPU will be unable in that case to write the
        exception stack frame. Only reset will recover from the resulting
        Double Bus Fault.
        limitations on MC68020+MC68851:
          This hardware is currently not supported.
        limitations on MC68030:
          - 3-byte transfers are not supported (occurring on misaligned
            longword accesses to page boundaries e.g. "tst.l $fff" (assumed
            4KByte page size))
          - locked accesses (tas/cas/cas2) are not supported
        limitations on MC68040:
          This hardware is currently not supported.
        limitations on MC68060:
          - misaligned access are not supported (occurring on accesses through
            a page boundary, for example "tst.l ($ffe)" (assumed 4 KByte page
            size))
          - locked accesses (tas/cas) are not supported
          - instructions which are located on a protected page and access the
            supervisor portion of the status register will be executed wrong
            (these instructions will always see the trace bit as 1 and the
            interrupt level as 7, any modification of the status register
            supervisor portion will be without effect)
          - movem instruction may access a protected area without creating a
            Access Fault exception (only the first bus cycle of the execution
            unit will be verified to match the protected area)
          - move16 and double precision operations (FPU) are unsupported
          - a "move (mem),(mem)" with overlapping source and destination
            address which generates an Access Fault because Misalignment
            will be executed wrong, for example "move.l ($ffc),($ffe)" where
            page $1000..$1fff is protected and memory before execution
            contains ($ffc)=$11112222,($1000)=$33334444, after execution
            $1000 contains $11114444 and not $22224444)
        Unsupported accesses will result in a "Exception 'Access Fault'"
        WHDLoad requester.

   NOTE
        requires ws_Version >= 6
        The MMU must be in use by WHDLoad, otherwise you will get WHDLoad
        requester "Unacceptable Arguments".
        Only accesses to the user and supervisor data stream are affected
        (this means not affected are: CPU space accesses (e.g. getting values
        from the vector table) and instruction stream accesses).

   SEE ALSO
        resload_ProtectReadWrite, resload_ProtectWrite, resload_ProtectRemove


WHDLoad/resload_ProtectReadWrite

   NAME
        resload_ProtectReadWrite -- mark memory as read and write protected

   SYNOPSIS
        resload_ProtectReadWrite(length, address)
                                   D0      A0
                                  ULONG   APTR

   FUNCTION
        Protects the specified memory against reading and writing by the
        processor.
        The memory to protect must be located inside BaseMem or ExpMem.

   INPUTS
        length  - size of the memory area to protect
        address - start address of the memory area to protect

   EXAMPLE
                ...
                moveq   #4,d0                   ;one longword
                lea     $64,a0                  ;address
                move.l  (_resload,pc),a2
                jsr     (resload_ProtectReadWrite,a2)
                ...

   RESULT
        A "Exception 'Access Fault'" WHDLoad requester if the protected memory
        is accessed.

   BUGS
        The amount of protected areas is currently limited to 16.
        The page where the SSP points to must not be protected. Because if a
        Access Fault occurs the CPU will be unable in that case to write the
        exception stack frame. Only reset will recover from the resulting
        Double Bus Fault.
        limitations on MC68020+MC68851:
          This hardware is currently not supported.
        limitations on MC68030:
          - 3-byte transfers are not supported (occurring on misaligned
            longword accesses to page boundaries e.g. "tst.l $fff" (assumed
            4 KByte page size))
          - locked accesses (tas/cas/cas2) are not supported
        limitations on MC68040:
          This hardware is currently not supported.
        limitations on MC68060:
          - misaligned access are not supported (occurring on accesses trough
            a page boundary, for example "tst.l ($ffe)" (assumed 4 KByte page
            size))
          - locked accesses (tas/cas) are not supported
          - instructions which are located on a protected page and access the
            supervisor portion of the status register will be executed wrong
            (these instructions will always see the trace bit as 1 and the
            interrupt level as 7, any modification of the status register
            supervisor portion will be without effect)
          - movem instruction may access a protected area without creating a
            Access Fault exception (only the first bus cycle of the execution
            unit will be verified to match the protected area)
          - move16 and double precision operations (FPU) are unsupported
          - a "move (mem),(mem)" with overlapping source and destination
            address which generates an Access Fault because Misalignment
            will be executed wrong, for example "move.l ($ffc),($ffe)" where
            page $1000..$1fff is protected and memory before execution
            contains ($ffc)=$11112222,($1000)=$33334444, after execution
            $1000 contains $11114444 and not $22224444)
        Unsupported accesses will result in a "Exception 'Access Fault'"
        WHDLoad requester.

   NOTE
        requires ws_Version >= 6
        The MMU must be in use by WHDLoad, otherwise you will get WHDLoad
        requester "Unacceptable Arguments".
        Only accesses to the user and supervisor data stream are affected
        (this means not affected are: CPU space accesses (e.g. getting values
        from the vector table) and instruction stream accesses).

   SEE ALSO
        resload_ProtectRead, resload_ProtectWrite, resload_ProtectRemove


WHDLoad/resload_ProtectRemove

   NAME
        resload_ProtectRemove -- remove protection from memory area

   SYNOPSIS
        resload_ProtectRemove(length, address)
                                D0      A0
                               ULONG   APTR

   FUNCTION
        Remove a previously set protection.
        The specified area must exactly match the previously protected area.

   INPUTS
        length  - size of the memory area to protect
        address - start address of the memory area to protect

   EXAMPLE
                ...
                moveq   #4,d0                   ;one longword
                lea     $64,a0                  ;address
                move.l  (_resload,pc),a2
                jsr     (resload_ProtectRemove,a2)
                ...

   RESULT

   BUGS

   NOTE
        requires ws_Version >= 6

   SEE ALSO
        resload_ProtectRead, resload_ProtectWrite, resload_ProtectWrite


WHDLoad/resload_ProtectSMC

   NAME
        resload_ProtectSMC -- detect self modifying code

   SYNOPSIS
        resload_ProtectSMC(length, address)
                             D0      A0
                            ULONG   APTR

   FUNCTION
        Enables automatic detection of self modifying code (SMC) in the
        selected area. The selected area will be write protected using the
        resload_ProtectWrite mechanism. Additional the trace mode will be
        activated and a special handler for trace exceptions installed.
        Each write access to the selected area will be logged to a private
        memory location. On each instruction executed inside the selected
        memory the trace handler verifies, if the instruction has been
        previously modified. If an executed instruction has been altered
        the installed program will be terminated and WHDLoad will show an
        requester informing about the SMC-detection.

        To determinate the size of instructions a table is used. This table
        contains the opcode size in words depending on the first instruction
        word. If the trace exception handler encounters a instruction with
        unknown size WHDLoad aborts with an "Internal Error #3". The reason
        for this maybe an illegal instruction, an instruction available only
        in higher processors than 68000 or an incompleteness of the internal
        instruction size table (IST). To check the reason make an coredump
        and see which instruction has caused the problem (the instruction
        before the actual PC because trace exception occurs after the
        execution of the traced instruction). Depending on the reason you have
        to aid this:
        - If it is an illegal instruction you have to fix the installed
          program by patching his code.
        - If there is an 68020+ instruction we have a problem, because the
          IST is designed only for 68000 instructions where the size of the
          instruction can be estimated by the first word and the largest
          possible instruction is 5 words. If the instruction size can be
          estimated by the first word you may add the instruction to a own
          IST (see below).
        - If there is an valid 68000 instruction please inform the WHDLoad
          author that he adds this instruction to the default IST inside
          WHDLoad. For the moment you may add this instruction to an own
          IST (see below)
        Using an own IST: During the initialization of this function
        WHDLoad searches first for an external IST. This must be located in
        the same directory where the WHDLoad executable resides and is
        searched as "PROGDIR:WHDLoad.IST". If there is no external IST the
        internal one is used. The source of the internal IST is included in
        source representation in the developer archive and can be used to
        build a external IST.

        Due the large exception overhead the execution speed in the selected
        area will strongly slow down. To improve performance it is therefore
        recommend to relocate the SSP to a Fast-Memory location using
        ws_ExpMem and appropriate initialistion and modification of the
        installed program.
        To maximize performance during the initialization of this function
        the BaseMem area will be set to NC, the ExpMem and Slave to CB and
        all caches will be enabled (resload_SetCPU).


   INPUTS
        length  - size of the memory area to protect
        address - start address of the memory area to protect

        The area to protect must be located inside the BaseMem or ExpMem.

   EXAMPLE

        enable SMC-detection for the area $10000..$3e000:
                ...
                move.l  #$2e000,d0              ;length
                lea     $10000,a0               ;address
                move.l  (_resload,pc),a2
                jsr     (resload_ProtectSMC,a2)
                ...

   RESULT

   BUGS
        Currently supported is only 68030 and 68060. For limitations and
        restrictions regarding the MMU related part of operation see the BUGS
        section of resload_ProtectWrite.
        You must not protect the page where the SSP points to, if you do so
        an Double Bus Fault will occur because the CPU will be unable to
        write the exception stack frame. Only reset will recover from a Double
        Bus Fault.

   NOTE
        requires ws_Version >= 10
        The MMU must be in use by WHDLoad, otherwise you will get WHDLoad
        requester "Unacceptable Arguments".
        There must be no resload_Protect* active at the same time.

   SEE ALSO
        resload_ProtectWrite, resload_SetCPU


WHDLoad/resload_ProtectWrite

   NAME
        resload_ProtectWrite -- mark memory as write protected

   SYNOPSIS
        resload_ProtectWrite(length, address)
                               D0      A0
                              ULONG   APTR

   FUNCTION
        Protects the selected area against writing by the processor.
        The area to protect must be located inside BaseMem or ExpMem.

   INPUTS
        length  - size of the memory area to protect
        address - start address of the memory area to protect

   EXAMPLE
                ...
                moveq   #4,d0                   ;one longword
                lea     $64,a0                  ;address
                move.l  (_resload,pc),a2
                jsr     (resload_ProtectWrite,a2)
                ...

   RESULT

   BUGS
        The amount of protected areas is currently limited to 16.
        The page where the SSP points to must not be protected. Because if a
        Access Fault occurs the CPU will be unable in that case to write the
        exception stack frame. Only reset will recover from the resulting
        Double Bus Fault.
        limitations on MC68020+MC68851:
          This hardware is currently not supported.
        limitations on MC68030:
          - 3-byte transfers are not supported (occurring on misaligned
            longword accesses to page boundaries e.g. "tst.l $fff" (assumed
            4 KByte page size))
          - locked accesses (tas/cas/cas2) are not supported
        limitations on MC68040:
          This hardware is currently not supported.
        limitations on MC68060:
          - misaligned access are not supported (occurring on accesses trough
            a page boundary, for example "tst.l ($ffe)" (assumed 4 KByte page
            size))
          - locked accesses (tas/cas) are not supported
          - instructions which are located on a protected page and access the
            supervisor portion of the status register will be executed wrong
            (these instructions will always see the trace bit as 1 and the
            interrupt level as 7, any modification of the status register
            supervisor portion will be without effect)
          - movem instruction may access a protected area without creating a
            Access Fault exception (only the first bus cycle of the execution
            unit will be verified to match the protected area)
          - move16 and double precision operations (FPU) are unsupported
          - a "move (mem),(mem)" with overlapping source and destination
            address which generates an Access Fault because Misalignment
            will be executed wrong, for example "move.l ($ffc),($ffe)" where
            page $1000..$1fff is protected and memory before execution
            contains ($ffc)=$11112222,($1000)=$33334444, after execution
            $1000 contains $11114444 and not $22224444)
        Unsupported accesses will result in a "Exception 'Access Fault'"
        WHDLoad requester.

   NOTE
        requires ws_Version >= 6
        The MMU must be in use by WHDLoad, otherwise you will get WHDLoad
        requester "Unacceptable Arguments".
        Only accesses to the user and supervisor data stream are affected
        (this means not affected are: CPU space accesses (e.g. getting values
        from the vector table) and instruction stream accesses).

   SEE ALSO
        resload_ProtectRead, resload_ProtectReadWrite, resload_ProtectRemove


WHDLoad/resload_Relocate

   NAME
        resload_Relocate -- relocate an AmigaDOS executable

   SYNOPSIS
        size = resload_Relocate(address, tags)
         D0                       A0      A1
        ULONG                    APTR   STRUCT

   FUNCTION
        Relocates a standard AmigaDOS executable in memory.

   INPUTS
        address - the start address of the executable in memory, this is the
                  source and also the destination address, i.e.
                  resload_Relocate will relocates the executable over itself
                  (a multi pass technique is used)
        tags    - there are two valid tags starting WHDLoad version 14.1
                  WHDLTAG_CHIPPTR - specifies a extra memory location where
                    to put hunks with the memory flag MEMF_CHIP
                  WHDLTAG_FASTPTR - specifies a extra memory location where
                    to put hunks with the memory flag MEMF_FAST
                  the different memory locations must not overlap, WHDLoad
                  will check that and report 'illegal args' if they do
                  starting WHDLoad version 15.1 there is another tag:
                  WHDLTAG_ALIGN - it specifies an alignment for the hunks,
                    the number given must be an positive integer which is
                    a power of 2, all hunk lengths will be rounded up to
                    a multiple of this value, useful is 8 to be compatible
                    with exec.AllocMem which is used by dos.LoadSeg
                  starting WHDLoad version 16.3 there is another tag:
                  WHDLTAG_LOADSEG - if specified the function creates a
                    segment list as if loaded via dos.LoadSeg,
                    resload_PatchSeg can be used to modify the relocated
                    executable

   EXAMPLE
                ...
                lea     (_main,pc),a0           ;name
                lea     $400,a3                 ;A3 = address for program
                move.l  a3,a1                   ;destination
                move.l  (_resload,pc),a2
                jsr     (resload_LoadFileDecrunch,a2)
                move.l  a3,a0                   ;address
                sub.l   a1,a1                   ;tags
                jsr     (resload_Relocate,a2)
                ...
                jmp     (a3)                    ;start the program
                ...

        _main   dc.b    "main-program",0

   EXAMPLE
                ...
                move.l  (_freefast),a0          ;address
                clr.l   -(a7)                   ;TAG_DONE
                move.l  (_freechip),-(a7)       ;chip area
                pea     WHDLTAG_CHIPPTR
                pea     8                       ;8 byte alignment
                pea     WHDLTAG_ALIGN
                move.l  a7,a1                   ;tags
                move.l  (_resload,pc),a2
                jsr     (resload_Relocate,a2)
                add.l   d0,(_freefast)
                add.l   (12,a7),(_freechip)
                add.w   #20,a7
                ...

   EXAMPLE
                ...
                move.l  (_freemem),a0           ;address
                clr.l   -(a7)                   ;TAG_DONE
                pea     -1                      ;true
                pea     WHDLTAG_LOADSEG
                pea     8                       ;8 byte alignment
                pea     WHDLTAG_ALIGN
                move.l  a7,a1                   ;tags
                move.l  (_resload,pc),a2
                jsr     (resload_Relocate,a2)
                add.w   #5*4,a7
                lea     (_patchlist),a0
                move.l  (_freemem),d0
                addq.l  #4,d0                   ;segment starts at offset 4
                lsr.l   #2,d0                   ;make BPTR
                move.l  d0,a1
                jsr     (resload_PatchSeg,a2)
                ...

   RESULT
        size - size of the relocated executable
               (this may be more or less than the size of the executable file,
               depending on if BSS hunks are contained in the executable)
        tags - the ti_Data field will be overwritten with the length of data
               stored in this area

   BUGS
        The routine supports all hunks supported by Kickstart 1.3 except
        OVERLAY. Anyway it is only tested with a limited amount of
        executables, so please report any problems or bugs.

   NOTE
        requires ws_Version >= 8
        The function uses stack for variables. The amount depends on the
        number of hunks in the executable and can be calculated as
        "used stack = hunks * 20 + 32".
        Upto WHDLoad version 16.9 the executable must not contain more than 256
        hunks (also AmigaDOS allows not more than 256 hunks). Starting WHDLoad
        version 17.0 512 hunks are supported. Beware of the stack space, for
        512 hunks more 10 KiB stack are required.
        The routine performs automatically a resload_FlushCache before
        returning.

   SEE ALSO


WHDLoad/resload_SaveFile

   NAME
        resload_SaveFile -- write memory to a file

   SYNOPSIS
        success,errorcode = resload_SaveFile(size, name, address)
          D0       D1                         D0    A0      A1
         BOOL     ULONG                     ULONG  CPTR    APTR

   FUNCTION
        Writes specified memory area to a file using the specified file name.
        If multiple data directories are used the file will be created
        always in the first data directory. Possible missing sub directories
        are only created by WHDLoad if the option SavePath/S is in use.

   INPUTS
        size    - amount of bytes to write
        name    - name of file to write
        address - memory address of buffer to write

   EXAMPLE
                ...
                move.l  #512,d0                 ;size
                lea     (_save,pc),a0           ;name
                lea     $5ac20,a1               ;source
                move.l  (_resload,pc),a2
                jsr     (resload_SaveFile,a2)
                ...

        _save   dc.b    "saved",0

   RESULT
        success   - TRUE on success
        errorcode - 0 on success
                    otherwise a DOS error code from dos.IoErr()
        If WHDLF_NoError is set, the function only returns on success.

   BUGS

   NOTE

   SEE ALSO
        resload_SaveFileOffset


WHDLoad/resload_SaveFileOffset

   NAME
        resload_SaveFileOffset -- write memory to a file at given offset

   SYNOPSIS
        success,error = resload_SaveFileOffset(size, offset, name, address)
          D0     D1                             D0     D1     A0      A1
         BOOL   ULONG                          ULONG  ULONG  CPTR    APTR

   FUNCTION
        Writes specified memory area to a file at specified offset using the
        specified file name.
        If multiple data directories are used the file will be written always
        in the first data directory. If the file is not preloaded and cannot
        be preloaded during this function call or the option NoWriteCache/S
        is used and the file doesn't exist in the first data directory but in
        any other data directory the call to this function will fail with DOS
        error code ERROR_OBJECT_EXISTS.
        Possible missing sub directories are only created by WHDLoad if the
        option SavePath/S is in use.

   INPUTS
        size    - amount of bytes to write
        offset  - offset in the file to write
        name    - name of file to write
        address - memory address of buffer to write

   EXAMPLE
                ...
                move.l  #512,d0                 ;size
                move.l  #$4000,d1               ;offset
                lea     (_save,pc),a0           ;name
                lea     $5ac20,a1               ;source
                move.l  (_resload,pc),a2
                jsr     (resload_SaveFileOffset,a2)
                ...

        _save   dc.b    "saved",0

   RESULT
        success   - TRUE on success
        errorcode - 0 on success
                    otherwise a DOS error code from dos.IoErr()
        If WHDLF_NoError is set, the function only returns on success.

   BUGS

   NOTE
        requires ws_Version >= 5

   SEE ALSO
        resload_SaveFile


WHDLoad/resload_SetCACR

   NAME
        resload_SetCACR -- set cacheability for BaseMem

   SYNOPSIS
        old = resload_SetCACR(new, mask)
         D0                    D0   D1
       ULONG                 ULONG ULONG

   FUNCTION
        This function enables/disables the cpu caches.
        The changes will affect the CACR (Cache Control Register) and
        the MMU-tables if the MMU is used by WHDLoad.

   INPUTS
        new  - new cache status
        mask - status bits to change

        valid values for new and mask are:
                CACRF_EnableI - instruction cache
                CACRF_EnableD - data cache
        (bits are defined in the standard include file "exec/execbase.i")

   EXAMPLE
        to enable instruction cache:
                ...
                move.l  #CACRF_EnableI,d0       ;new status
                move.l  d0,d1                   ;status to change
                move.l  (_resload,pc),a2
                jsr     (resload_SetCACR,a2)
                ...

   RESULT
        old - old cache status

   BUGS

   NOTE
        It is safe to call this routine from User or Supervisor mode and
        independent from the actual CPU type (also on 68000/010).
        If WHDLoad is launched with the option NoCache/S this routine will
        return without changing anything (all memory is always noncacheable).
        Don't be surprised if you see in the coredump or in a freezer that
        caches are enabled even if not enabled by the Slave. Because if the
        MMU is used by WHDLoad and no caches are switched on by the Slave,
        WHDLoad marks the BaseMem using the MMU as noncacheable-serialized
        and enables both caches so that the memory of WHDLoad and the Slave
        are still cacheable to increase the performance.
        The caches are flushed after returning from this routine.

   SEE ALSO
        resload_SetCPU, resload_FlushCache


WHDLoad/resload_SetCPU

   NAME
        resload_SetCPU -- control CPU setup

   SYNOPSIS
        old = resload_SetCPU(new, mask)
         D0                   D0   D1
       ULONG                ULONG ULONG

   FUNCTION
        This function changes the cacheability of memory areas and changes the
        CPU setup.
        The changes will affect the CACR (Cache Control Register) on 68020-60,
        the PCR (Processor Configuration Register) on 68060 and the MMU-tables
        if the MMU is used by WHDLoad.
        Check the WHDLoad manual section "CPU Cache Handling" for further
        informations. See the include file "whdload.i" for supported bit sets.

   INPUTS
        new  - new setup
        mask - parts of the current setup to change

   EXAMPLE
        to enable the only instruction cache for BaseMem and ExpMem:
                ...
                move.l  #WCPUF_Base_WT|WCPUF_Exp_CB|WCPUF_IC,d0
                move.l  #WCPUF_Base|WCPUF_Exp|WCPUF_IC|WCPUF_DC,d1
                move.l  (_resload,pc),a2
                jsr     (resload_SetCPU,a2)
                ...

   RESULT
        old - the setup before

   BUGS

   NOTE
        requires ws_Version >= 10
        It is safe to call this routine from User or Supervisor mode and
        independent from the actual CPU type (also on 68000/010).
        If WHDLoad is launched with the option NoCache/S this routine will
        return without changing anything (all memory is always noncacheable).
        Don't be surprised if you see in the coredump or in a freezer that
        caches are enabled even if not enabled by the Slave. Because if the
        MMU is used by WHDLoad and caches are disabled by the Slave,
        WHDLoad marks the memory using the MMU as noncacheable-serialized
        and enables both caches so that the memory of WHDLoad is still
        cacheable to increase the performance.
        The caches are flushed after returning from this routine.

   SEE ALSO



WHDLoad.Slave/--Overview--

The WHDLoad.Slave contains the interface code which makes the installed
program able to load his files from harddisk. Additional it should realize
the possibility to quit the program to return to the OS.

   FORMAT
        Is a standard AmigaDOS executable.
   ATTENTION
        The Slave MUST consist of only ONE hunk (ONE section).
        The Slave MUST be 100% PC-relative (must not contain relocations).
        It may contain debug/symbol hunks which are ignored.

   STRUCTURE
        At the top of the Slave is the "WHDLoadSlave" structure. After this
        follows the specific code and data.

             STRUCTURE  WHDLoadSlave,0
                STRUCT  ws_Security,4
                STRUCT  ws_ID,8
                UWORD   ws_Version
                UWORD   ws_Flags
                ULONG   ws_BaseMemSize
                ULONG   ws_ExecInstall
                RPTR    ws_GameLoader
                RPTR    ws_CurrentDir
                RPTR    ws_DontCache
             (  LABEL   ws_SIZEOF_pre_v4  )
                UBYTE   ws_keydebug
                UBYTE   ws_keyexit
             (  LABEL   ws_SIZEOF_pre_v8  )
                ULONG   ws_ExpMem
             (  LABEL   ws_SIZEOF_pre_v10 )
                RPTR    ws_name
                RPTR    ws_copy
                RPTR    ws_info
             (  LABEL   ws_SIZEOF_pre_v16 )
                RPTR    ws_kickname
                ULONG   ws_kicksize
                UWORD   ws_kickcrc
             (  LABEL   ws_SIZEOF_pre_v17 )
                RPTR    ws_config
                LABEL   ws_SIZEOF

        ws_Security
                Contains the code
                        moveq #-1,d0
                        rts
                to avoid problems if somebody tries execute the Slave directly.

        ws_ID
                Contains the string "WHDLOADS" to identify the program as a
                WHDLoad Slave.

        (use the macro SLAVE_HEADER defined in the include file "whdload.i" to
        create the entries ws_Security and ws_ID)

        ws_Version
                Contains the version of WHDLoad that is required by the Slave.
                Some resload functions need at least a specific version of
                WHDLoad. E.g. to use resload_CRC16 you must set ws_Version
                to 3 or higher.
                On the other side the size of the WHDLoad Slave structure
                differs for different Slave versions. I.e. if you set
                ws_Version to 16 or higher you MUST also initialize the fields
                up to ws_kickcrc (even if you don't use a Kickstart image).

        ws_Flags
                WHDLF_Disk / WHDLB_Disk
                   This flag should be enabled if the program uses disk images.
                   As a result Preload/S is working slightly different.
                   (starting WHDLoad 0.143 this flag is obsolete)
                WHDLF_NoError / WHDLB_NoError
                   If enabled every error occurring in a resload_#? function
                   forces WHDLoad to quit immediately and showing an error
                   requester about the reason.
                   Using this flag makes it unnecessary for the Slave to check
                   the return codes of resload_#? functions. The Slave can then
                   be sure that if a function returns it was successful (this
                   will make the Slave more simple).
                WHDLF_EmulTrap / WHDLB_EmulTrap
                   This flag has only effect if the VBR is moved by WHDLoad
                   (i.e. the machine is at least a 68010 and the tooltype
                   NoVBRMove is not set).
                   If the flag is set all "Trap #0..15"'s are emulated by the
                   exception handler inside WHDLoad. I.e. the handler checks
                   if the appropriate trap vector ($80-$bc) is initialized,
                   and if the routine at the vector address will be called by
                   WHDLoad.
                WHDLF_NoDivZero / WHDLB_NoDivZero
                   This flag has only effect if the VBR is moved by WHDLoad
                   (i.e. the machine is at least a 68010 and the tooltype
                   NoVBRMove is not set).
                   If the flag is set and a "Division by Zero" exception
                   occurs WHDLoad will not quit with an requester, but a
                   RTE will be performed.
                   This maybe useful if the demo/game performs randomly
                   divisions by zero.
                WHDLF_Req68020 / WHDLB_Req68020
                   This flag indicates that the Slave/installed program
                   requires at least a MC68020 CPU. WHDLoad will check at
                   startup if this requirement is fulfilled. If it doesn't the
                   program will be terminated with an appropriate requester.
                WHDLF_ReqAGA / WHDLB_ReqAGA
                   This flag indicates that the Slave/installed program
                   requires at least the AGA chipset. WHDLoad will check at
                   startup if this requirement is fulfilled. If it doesn't the
                   program will be terminated with an appropriate requester.
                WHDLF_NoKbd / WHDLB_NoKbd
                   This flag tells WHDLoad that it doesn't should acknowledge
                   the keyboard if a key was pressed. This must be used with
                   programs which doesn't check the keyboard from the PORTS
                   interrupt ($68). Background information: In normal
                   operation when NoVBRMove is inactive, WHDLoad checks if a
                   key was pressed on each interrupt. If a key has been
                   pressed it checks the rawkey code against QuitKey, DebugKey
                   and FreezeKey. If it doesn't match any of them it checks if
                   there is an initialized PORTS interrupt ($68). If there is
                   no one it replies the keyboard that the keycode has been
                   received. Therefore when the installed program later checks
                   the keyboard from e.g. the VBI, it will never receive any
                   keycodes. This flag avoids this behavior.
                WHDLF_EmulLineA / WHDLB_EmulLineA
                   This flag has only effect if the VBR is moved by WHDLoad
                   (i.e. the machine is at least a 68010 and the tooltype
                   NoVBRMove is not set).
                   If the flag is set all exceptions "Line-A" (caused by
                   opcodes starting with %1010) are emulated by the
                   exception handler inside WHDLoad. I.e. the handler checks
                   if the vector ($28) is initialized and if the routine to
                   which the vector points will be called by WHDLoad.
                WHDLF_EmulTrapV / WHDLB_EmulTrapV
                   This flag has only effect if the VBR is moved by WHDLoad
                   (i.e. the machine is at least a 68010 and the tooltype
                   NoVBRMove is not set).
                   If the flag is set all exceptions caused by a "TrapV"
                   instruction are emulated by the exception handler inside
                   WHDLoad. I.e. the handler checks if the vector ($1C) is
                   initialized and if the routine to which the vector points
                   will be called by WHDLoad.
                WHDLF_EmulChk / WHDLB_EmulChk
                   This flag has only effect if the VBR is moved by WHDLoad
                   (i.e. the machine is at least a 68010 and the tooltype
                   NoVBRMove is not set).
                   If the flag is set all exceptions caused by a "Chk/Chk2"
                   instruction are emulated by the exception handler inside
                   WHDLoad. I.e. the handler checks if the vector ($18) is
                   initialized and if the routine to which the vector points
                   will be called by WHDLoad.
                WHDLF_EmulPriv / WHDLB_EmulPriv
                   This flag has only effect if the VBR is moved by WHDLoad
                   (i.e. the machine is at least a 68010 and the tooltype
                   NoVBRMove is not set).
                   If the flag is set all privilege violation exceptions are
                   emulated by the exception handler inside WHDLoad. I.e. the
                   handler checks if the vector ($20) is initialized and if
                   the routine to which the vector points will be called by
                   WHDLoad.
                WHDLF_EmulLineF / WHDLB_EmulLineF
                   This flag has only effect if the VBR is moved by WHDLoad
                   (i.e. the machine is at least a 68010 and the tooltype
                   NoVBRMove is not set).
                   If the flag is set all exceptions "Line-F" (caused by
                   opcodes starting with %1010) are emulated by the
                   exception handler inside WHDLoad. I.e. the handler checks
                   if the vector ($2C) is initialized and if the routine to
                   which the vector points will be called by WHDLoad.
                WHDLF_ClearMem / WHDLB_ClearMem
                   If that flag is set WHDLoad will not init BaseMem with the
                   pattern $CCCCCCCC and ExpMem with $DDDDDDDD but simply
                   clear these memories.
                WHDLF_Examine / WHDLB_Examine
                   This flag must be set if the functions
                   resload_Examine/ExNext will be used. It causes WHDLoad to
                   cache informations about all files and directories. This
                   consumes memory and takes time at startup. Therefore it
                   shouldn't be used without necessity.
                WHDLF_EmulDivZero / WHDLB_EmulDivZero
                   This flag has only effect if the VBR is moved by WHDLoad
                   (i.e. the machine is at least a 68010 and the tooltype
                   NoVBRMove is not set).
                   If the flag is set all division by zero exceptions are
                   emulated by the exception handler inside WHDLoad. I.e. the
                   handler checks if the vector ($14) is initialized and if
                   the routine to which the vector points to will be called by
                   WHDLoad.
                   This flag has precedence over the flag NoDivZero.
                WHDLF_EmulIllegal / WHDLB_EmulIllegal
                   This flag has only effect if the VBR is moved by WHDLoad
                   (i.e. the machine is at least a 68010 and the tooltype
                   NoVBRMove is not set).
                   If the flag is set all illegal instruction exceptions are
                   emulated by the exception handler inside WHDLoad. I.e. the
                   handler checks if the vector ($10) is initialized and if
                   the routine to which the vector points will be called by
                   WHDLoad.

        ws_BaseMemSize
                The size of the memory that is required by the program.
                The BaseMemory starts at $00000000 and ends at ws_BaseMemSize.
                BaseMemory is always ChipMem.
                This value must be multiple of $1000.
                The valid minimum is $2000 and the maximum is $200000.

        ws_ExecInstall
                obsolete, must be set to 0

        ws_GameLoader
                A relative (to the start of the structure) 16-bit pointer
                to the start code of the Slave.

        ws_CurrentDir
                A relative (to the start of the structure) 16-bit pointer
                to a 0 terminated string which is the name of the path
                where all files are stored (sub directory).
                If no sub directory is used initialize this with 0.
                The path to the sub directory must be relative (must not
                contain ":").

        ws_DontCache
                A relative (to the start of the structure) 16-bit pointer
                to a 0 terminated string which is a standard AmigaDOS
                pattern (dos.ParsePattern, dos.MatchPattern).
                All files matching this pattern are not cached by WHDLoad.
                If you don't want to use it set the entry to 0.
                Starting WHDLoad version 0.107 this is obsolete, because saved
                files will be written also to the file cache.

      The following variables are only evaluated by WHDLoad if ws_Version
      is set to >= 4. The following variables MUST be initialized if you set
      ws_Version to >= 4.

        ws_keydebug
                The raw key code to exit and writing debug files.
                This variable will be overwritten by WHDLoad using the value
                specified with the option DebugKey/K/N if set.
                If the Slave provides an own handler to support a debug option
                via the keyboard it should use this value for comparison. So
                it will be possible to the user to change the key suggested
                by the Slave.
                WHDLoad itself also checks for this key code on each interrupt
                if the VBR is moved (requires 68010+ and that NoVBRMove/S is
                not set).
                If the variable is set to 0 WHDLoads default will be used.
                Starting WHDLoad version 17.0 the contents of this variable
                is ignored. It will be always overwritten by WHDLoad with the
                default or the specified DebugKey/K/N.
                Recommend value is 0.

        ws_keyexit
                The raw key code to exit.
                This variable will be overwritten by WHDLoad using the value
                specified with the option QuitKey/K/N if set.
                If the Slave provides an own handler to support a quit option
                via the keyboard it should use this value for comparison. So
                it will be possible to the user to change the key suggested
                by the Slave.
                WHDLoad itself also checks for this key code on each interrupt
                if the VBR is moved (requires 68010+ and that NoVBRMove/S is
                not set).
                Recommend value is $59 = "F10".

      The following variables are only evaluated by WHDLoad if ws_Version
      is set to >= 8. The following variables MUST be initialized if you set
      ws_Version to >= 8.

        ws_ExpMem
                If the installed program requires expansion memory, the size
                must be specified here. WHDLoad will allocate a memory block
                of this size and writes a pointer to the start of the
                allocated memory back to this entry. The memory is granted to
                be aligned to $1000 (4096 bytes). The size specified must be
                a multiple of $1000 (4096). If WHDLoad fails to allocate
                this memory it terminates with an appropriate error requester.
                That means the Slave will always get a valid pointer here.
                Starting WHDLoad version 10.2 the value can be negative. A
                negative size means that the memory is optional and not
                required. WHDLoad will try to allocate it and if it fails it
                will set ws_ExpMem to zero. Therefore the Slave has to check
                the contents of ws_ExpMem.

      The following variables are only evaluated by WHDLoad if ws_Version
      is set to >= 10. The following variables MUST be initialized if you set
      ws_Version to >= 10.

        ws_name
                A relative (to the start of the structure) 16-bit pointer
                to a 0 terminated string containing the name of the installed
                program. e.g. "Super Hang Off"

        ws_copy
                A relative (to the start of the structure) 16-bit pointer
                to a 0 terminated string containing the copyright of the
                installed program. The string should start with the year
                followed by the company holding the copyright. Multiple years
                or companies should be separated with ", ".
                e.g. "1983 Schega, 1989 Bad Dreams"

        ws_info
                A relative (to the start of the structure) 16-bit pointer
                to a 0 terminated string containing additional infos about the
                installed program. The string may also contain line feeds
                ($0a). The character -1 has a special meaning. It results in
                a line feed and an additional vertical skip of the half font
                height. e.g.:
                        dc.b    "installed & fixed by Wepl",10
                        dc.b    "version 1.4 (06.06.2066)",-1
                        dc.b    "greetings to the world",0

      The following variables are only evaluated by WHDLoad if ws_Version
      is set to >= 16. The following variables MUST be initialized if you set
      ws_Version to >= 16.

        ws_kickname
                A relative (to the start of the structure) 16-bit pointer
                to a 0 terminated string containing the name of the Kickstart
                image to be loaded by WHDLoad to ExpMem. The path
                "DEVS:Kickstarts/" will be prepended by WHDLoad to find the
                file. e.g. "kick34005.A500"

        ws_kicksize
                The size of the Kickstart image to load.

        ws_kickcrc
                The CRC16 checksum for the Kickstart image to load.

        Starting WHDLoad 16.1 there is a special mode which supports multiple
        Kickstart images within the same Slave. The special mode is activated
        by using -1 as the value for ws_kickcrc. ws_kickname contains then a
        relative pointer to a table which contains pairs of CRC16 and relative
        pointers to a Kickstart name. The table is terminated with a CRC16 of
        0. WHDLoad will try to load Kickstarts from the table until it finds
        one with the correct CRC16. After the successful load the CRC16 of the
        loaded Kickstart image will be placed in ws_kickcrc (overwriting the
        -1) so the Slave can recognize which Kickstart image has been loaded.

      The following variables are only evaluated by WHDLoad if ws_Version
      is set to >= 17. The following variables MUST be initialized if you set
      ws_Version to >= 17.

        ws_config
                A relative (to the start of the structure) 16-bit pointer
                to a 0 terminated string containing infos about configuration
                items to be displayed in the WHDLoad startup splash window.
                Possible items are the options ButtonWait and Custom1-5. For
                each item specified here a gadget will be added to the splash
                window, allowing the user easily the modify this option.
                The syntax in a EBNF is as follows:

                Config = ConfigOption { ";" ConfigOption } ;
                ConfigOption = Option [ ":" Type ":" Label [ ":" Spec ] ] ;
                Option = "BW" | "C1" | "C2" | "C3" | "C4" | "C5" ;
                        (* BW - ButtonWait, without Type  *)
                        (* C1..C5 - Custom1..5, requires Type *)
                Type = "B" | "L" | "0" ;
                        (* B - Boolean *)
                        (* X - Boolean only 1 bit used, Spec is the bit number
                               0-31 *)
                        (* L - List of values, cycle gadget, Spec is list of
                               SpecOptions *)
                Spec = Number | ( SpecOption { "," SpecOption } ) ;
                Number = [0-9] ;
                SpecOption = Label ;
                Label = CHR(32..255) except [,:;] ;

                On Type=Boolean (also ButtonWait) the result will be 0 for
                unchecked and 1 for checked. On Type=List the result will be
                0 for the first SpecOption and is incremented by 1 for each
                subsequent SpecOption.

                Example:

                dc.b    "BW;"
                dc.b    "C1:B:Skip Intro;"
                dc.b    "C2:X:Activate Trainer:0;"
                dc.b    "C3:L:Load Game Position:None,1,2,3,4,5,6,7,8,9;"
                dc.b    "C4:L:Brightness:default,+50%,+100%"
                dc.b    0

   CONVENTIONS for ws_GameLoader
        Following the status of the system at the moment of calling
        ws_GameLoader:

        CPU:
                SR   = $2000           Supervisor-mode, all interrupts enabled
                SSP  = ws_BaseMemSize  at the end of BaseMem
                USP  = SSP-$400        at the end of BaseMem - 1024
                A0   = ResidentLoader  pointer to the resident Jump-Tower
                D0-D7/A1-A6 random     (D0=$d0d0d0d0 D1=...)

                Nothing more is interesting from the Slave programmers point
                of view. All special registers like VBR,SFC,DFC,CAAR,CACR,MSP,
                TC,MMUSR,CRP,SRP,URP,TT0,TT1,DTT0,DTT1,ITT0,ITT1,PCR,BUSCR are
                WHDLoad private and MUST NOT BE CHANGED.

        FPU:
                At the moment not initialized by WHDLoad.

        BaseMem:
                $00000000.l = 0
                $00000004.l = $f0000001
                        an odd value to make any try to use it (the execbase)
                        creating an "Address Error" or "Access Fault" exception
                $00000008...$00000400
                        if WHDLoad has moved the VBR it contains $CCCCCCCC
                        else it contains a pointer to an exception handler
                        inside WHDLoad
                $00000400...ws_BaseMemSize
                        contains $CCCCCCCC, this memory fill pattern is used to
                        easily recognize modified memory
                $00001000.l = $FFFFFFFE
                        the copper instruction "CWAIT $ff,$1fe" (CEND)

        ExpMem:
                the memory is filled with the pattern $DDDDDDDD

        custom registers:
                dmacon = 0             all DMAs off
                intena = 0             all interrupts off
                cop1lc = cop2lc = $1000
                a AGA-machine is switched to OCS

        cias:
                ------- ciaa ------     ------- ciab ------
                pra in  = %00000000     pra in  = %00000000
                pra out = %11111100     pra out = %11111000
                ddra    = %00000011     ddra    = %11000000
                prb in  = %00000000     prb in  = %00000000
                prb out = %00000000     prb out = %11111111
                ddrb    = %00000000     ddrb    = %11111111
                ta      =     $21ff     ta      =     $ffff
                tb      =     $21ff     tb      =     $ffff
                event   =   $000000     event   =   $000000
               (alarm   =   $ffffff     alarm   = execbase.EClockFrequency
                        the alarm values are no longer initialized starting
                        WHDLoad version 13.1 to avoid compatibility problems
                        on Kickstart 2.0)
                sdr     =       $00     sdr     =       $00
                icr     = %00000000     icr     = %00000000
                icm     = %00001000     icm     = %00000000
                cra     = %00000000     cra     = %00000000
                crb     = %00000000     crb     = %00000000

   SEE ALSO
        example Slaves