v4.0/src/MAPPER/IOCTL.ASM

   1 page 80,132
   2
   3 title CP/DOS DosDevIOCTl   mapper
   4
   5 dosxxx  segment byte public 'dos'
   6         assume  cs:dosxxx,ds:nothing,es:nothing,ss:nothing
   7 ;
   8 ;**********************************************************************
   9 ;*
  10 ;*   MODULE:   dosdevioctl
  11 ;*
  12 ;*   FILE NAME: dos007.asm
  13 ;*
  14 ;*   CALLING SEQUENCE:
  15 ;*
  16 ;*       push@     dword   Data
  17 ;*       push@     dword   Paramlist
  18 ;*       push      word    Function
  19 ;*       push      word    Category
  20 ;*       push@     word    Devicehandle
  21 ;*
  22 ;*       call      doschgfileptr
  23 ;*
  24 ;*   MODULES CALLED:  PC-DOS Int 21h, ah=42h, move file pointer
  25 ;*
  26 ;*********************************************************************
  27
  28             public   dosdevioctl
  29             .sall
  30             .xlist
  31             include  macros.inc
  32             .list
  33
  34 str         struc
  35 Old_bp      dw       ?
  36 Return      dd       ?
  37 Handle      dw       ?       ; handle
  38 Category    dw       ?       ; device category
  39 Function    dw       ?       ; device function
  40 Parmlist    dd       ?       ; command arguments
  41 Data        dd       ?       ; data area
  42 str         ends
  43
  44 dosdevioctl     proc  far
  45         Enter   dosdevioctl           ; push registers
  46
  47         mov     bx,[bp].handle        ; get handle
  48
  49         cmp     bx,0ffe5h             ; is it a device handle ??
  50         jl      filehandle            ; branch if not
  51
  52 ; Convert DASD device handle to drive number as follows:
  53 ;  Drive        Open    IOCTL
  54 ;  Letter       Handle  DASD #
  55 ; -----------------------------
  56 ;    A           -2      1
  57 ;    B           -3      2
  58 ;    C           -4      3
  59 ;    D           -5      4
  60 ;    E           -6      5
  61         neg     bx                    ; convert dev handle to
  62         dec     bx                    ; drive number
  63
  64 filehandle:
  65         mov     ax,[bp].function      ; get function code
  66         cmp     ax,020H               ; check for right function
  67         je      continue1             ; continue if right function code
  68         mov     ax,01H                ; else, load error code
  69         jmp     exit                  ; return
  70
  71 continue1:                            ; only category 8 is supported
  72         mov     ax,[bp].category      ; set category
  73
  74         mov     ah,44h
  75         int     21h                   ; do ioctl
  76         jnc     continue              ; check for error
  77
  78         cmp     ax,1                  ; if error and return code = 1
  79         jne     exit                  ; then it is network drive
  80                                       ; therefore continue
  81 continue:
  82         lds     si,[bp].data          ; media changable
  83         mov     byte ptr [si],al      ; save in data area
  84         xor     ax,ax                 ; set no error coe
  85
  86 exit:   mexit                         ; pop registers
  87         ret     size str - 6          ; return
  88
  89 dosdevioctl  endp
  90
  91 dosxxx      ends
  92
  93             end