ProfitPress Mega CDROM2 Shareware Freeware (MSDOS)(1992)(Eng)

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/ ProfitPress Mega CDROM2 …eeware (MSDOS)(1992)(Eng) / ProfitPress-MegaCDROM2.B6I / UTILITY / SYSTEM / IDRV01.ZIP / REMDRV.ASM < prev next >

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Assembly Source File | 1991-11-19 | 14.6 KB | 605 lines

PAGE 80,132 NAME remdrv ;:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::; ; LUBLIN 24-02-1989 ; ; remdrv (v1.03) ; ; by JW ; ;...............................................................................; ASSUME DS:code, SS:code ,CS:code ,ES:code code SEGMENT Para Public 'code' ORG 100h start: jmp starter ; jump over data ;................................................................................. lf equ 0ah ; line feed cr equ 0dh ; carriage return ZERO equ 0 TAB equ 9 DIB_SIZE equ 21h FIRST_DIB equ 26h FIRST_DA equ 3ch NUM_OF_DRV equ 46h TOTAL_NUM equ 47h ;............................................................................... two db 2 dos_dep dw 0 ;0 - if dos 3.xx, 6 - if dos 4.xx or 5.xx dos_dep2 db 0 ;0 - if dos 3.xx, 7 - if dos 4.xx or 5.xx dos_dep3 dw 0 ;0 - if dos 3.xx, 1 - if dos 4.xx or 5.xx flags db 0 ;1 - device was loaded by Idrv drv_num db 0 ;current drive number dos_seg dw 0 ;IMBDOS segment drv_beg dw 0 ;Start of driver (must be on para boundry) DIB_offs dw 0 ;Address of ... DIB_seg dw 0 ; ... driver's DIB header_offs dw 0 header_seg dw 0 last_offs dw 0 ;Address of ... last_seg dw 0 ; ... DIB to be last xms_offs dw 0 xms_seg dw 0 DA_flag db 0 ;non zero if proper Drive Area found dev_flag db 0 ;set to 1 if block device dev_count db 0 buf db 10 dup (0) ;area for device driver name TXT_LEN equ $ - buf first_dev db 0 db ': - ' last_dev db 0 db ': ' PATT_LEN equ $ - first_dev one_dev db 0 db ':' db 9 dup (' ') ONLY_ONE equ $ - one_dev signature db 'IdrvCB ' SIG_LEN equ $ - signature ;...................................................................................... ;............................................................................... starter: lea dx,header call print_msg mov ah,30h int 21h ;Get DOS version number lea dx,err_txt cmp al,3 jb pr_txt check_ver: je get_list ;DOS v3.xx cmp al,5 ;ver. above 5 ? ja pr_txt ;yes,jump mov dos_dep,6 ;No,change entry length of Open Files Table mov dos_dep2,7 ;Change entry length of Drive Area mov dos_dep3,1 ;Change entry length of Disk Info Block get_list: mov ah,52h int 21h ;Get vector for int 25H mov dos_seg,es lea dx,not_PC_Dos cmp word ptr es:52h,'UN' ;NUL device ? jne pr_txt ;No,jump les di,dword ptr es:02ah ;get address of DOS file table add di,dos_dep ;change entry length of OFT if necessary cmp byte ptr es:[di + 05bh],'C' ;Entry for dev. CON ? jne pr_txt cmp word ptr es:[di + 05ch],'NO' je go_on pr_txt: jmp exit ;Jump to print message and qiut go_on: jmp ldrv ;............................................................................... ;............................................................................... ; messages to display db 'Program written by Janusz Wojcik',cr,lf err_txt db 'IDrv: That version of DOS is not supported!',cr,lf,lf,'$' not_PC_Dos db 'IDrv: Not PC DOS ',cr,lf,lf,'$' unlink_OK db cr,lf,'Device Driver uninstalled!',cr,lf,'$' unlink_err db cr,lf,"Can't uninstall device driver!",cr,lf,'$' unlink_quit db cr,lf,"Device driver not uninstalled!",cr,lf,'$' header db 'Device Drivers Uninstaller v1.03',cr,lf db '(C) 1990 by Janusz Wojcik Lublin,Poland.',cr,lf,lf,'$' intro db 'This is device ','$' not_idrv_dev db cr,lf,'Not loaded by Idrv !','$' inquiry db cr,lf,'Delete it (y/n) ?','$' ;.................................................................................... ;............................................................................... device_header struc next_offs dw ? next_seg dw ? dev_attr dw ? dev_strategy dw ? dev_interrupt dw ? name_unit db 8 dup(?) device_header ends ;............................................................................... ;............................................................................... ; the program body ;.............................................................................. ldrv: mov es,dos_seg mov si,48h les si,dword ptr es:[si] ;Address of next dev. header call copy_name ;get device driver name call check_type ;check whether character or block device call print_name ;display driver name call check_icb ;check if Idrv Control Block precedes Device Header lea dx,inquiry call print_msg ;ask if remove device driver mov ah,1 int 21h ;get char from stdin cmp al,'y' ;remove dev. driver ? je check_attr lea dx,unlink_quit jmp exit_OK check_attr: mov ax,es:dev_attr[si] test ah,80h ;Character device ? jnz unlnk_dev ;Yes,jump to unlink device headers mov ax,es mov dx,si mov header_offs,dx mov header_seg,ax call seek_DIB ;Seek DIB pointing to ES:SI jc exit_err mov ax,DIB_offs mov last_offs,ax mov ax,DIB_seg mov last_seg,ax find_CDS: mov si,es mov dx,bx mov DA_flag,ZERO call seek_DA ;Seek DA poniting to ES:BX cmp DA_flag,ZERO jz exit_err mov dx,header_offs mov ax,header_seg call seek_DIB jnc find_CDS chain_end: les bx,dword ptr last_offs mov si,dos_dep3 mov word ptr es:[si + bx + 18h],0ffffh ;Mark DIB as the last DIB mov al,byte ptr es:[bx] inc al mov es,dos_seg mov byte ptr es:NUM_OF_DRV,al ;Set real number of drives unlnk_dev: call unlink_dev ;Link device headers lea dx,unlink_OK jmp exit_OK exit_err: lea dx,unlink_err exit_OK: exit: call print_msg mov ah,4ch ;EXIT mov al,1 ;Set return code int 21h ;............................................................................... print_msg: mov ah,9 int 21h ret ;.............................................................................. ; copy_name: ; copy device driver name from Device Header into local buffer ; INPUT: ; ES:SI - address of Device Header for device ;.............................................................................. copy_name: push si push es push ds mov ax,es:dev_attr[si] test ah,80h ;Character device ? jnz copy ;Yes,skip mov dev_flag,1 ;Signal that block device copy: mov cx,4 mov di,offset buf push es pop ds ;DS = ES add si,10 push cs pop es ;ES = CS cld rep movsw ;copy device name quit_copy: pop ds pop es pop si ret ;................................................................................ ; check_type: ; check if block device. ; Prepare for displaying device name if so. ; INPUT: ; ES:SI - address of Device Header for device ;................................................................................ check_type: cmp dev_flag,1 jne quit_check push es push si mov ax,es mov dx,si call seek_DIBs inc first_dev add first_dev,40h mov al,first_dev mov last_dev,al mov al,dev_count dec al add last_dev,al pop si pop es quit_check: ret ;............................................................................... ; seek_DIBS: ; find number of the first and the last device ; AX:DX - address of Device Header for device ;............................................................................... seek_DIBs proc near push es push si mov es,dos_seg les bx,es:FIRST_DIB ;Get address of first DIB mov si,dos_dep3 next_DIB_in_chain: cmp word ptr es:[si + bx + 12h],dx jnz if_last_DIB cmp word ptr es:[si + bx + 14h],ax jnz if_last_DIB cmp dev_count,0 ;first matched device ? jnz inc_count ;No,jump mov cl,es:[bx] ;get device number mov first_dev,cl inc_count: inc dev_count if_last_DIB: cmp word ptr es:[si + bx + 18h],0ffffh ;The last DIB ? jz seek_DIBS_end ;Yes,jump les bx,dword ptr es:[si + bx + 18h] ;Get addr. of next DIB jmp next_DIB_in_chain seek_DIBs_end: pop si pop es clc ret seek_DIBs endp ;............................................................................... ; print_name: ; display device driver name ;............................................................................... print_name: push es push si lea dx,intro call print_msg mov cx,TXT_LEN mov dx,offset buf cmp dev_flag,0 ;Character device? je call_DOS ;Yes,jump cmp dev_count,1 ;More than one device ? jnz not_one_dev ;Yes,jump mov cl,first_dev mov one_dev,cl mov dx,offset one_dev mov cx,ONLY_ONE jmp call_DOS not_one_dev: mov dx,offset first_dev mov cx,PATT_LEN call_DOS: mov ah,40h mov bx,1 int 21h pop si pop es ret ;............................................................................... ; check_icb: ; check if Idrv Control Block precedes Device Header ; INPUT: ; ES:SI - address of Device Header for device ;............................................................................... check_icb: push es push si or flags,1 xor di,di mov ax,es dec ax mov es,ax mov si,offset signature mov cx,SIG_LEN repz cmpsb jz check_icb_end and flags,NOT(1) lea dx,not_idrv_dev call print_msg check_icb_end: pop si pop es ret page;.......................................................................... ; unlink_dev: ....... ; remove Device Header from the chain of Device Headers ....... ;.............................................................................. unlink_dev: mov es,dos_seg mov si,48h push es les si,dword ptr es:[si] ;Address of next dev. header mov bx,es:dev_attr[si] test bl,1 ;Stdin ? jz dechain ;No,jump push es push si call seek_stdin jc quit_unlink mov es,dos_seg mov es:32h,si ;Change pointer to ... mov es:34h,ax ; ... Stdin les bx,es:02ah ;Get address of DOS file table add bx,dos_dep ;change entry length of OFT if necessary mov es:[bx + 042h],si ;Change address of dev.header ... mov es:[bx + 044h],ax ; ... in Open Files Table pop si pop es dechain: call free_xms mov ax,es:next_offs[si] mov bx,es:next_seg[si] pop es cli mov es:48h,ax mov es:4ah,bx sti jmp quit_unlink test_clk: test bl,8 ;Is it clock device ? jz quit_unlink ;No,jump mov es:2eh,word ptr ZERO mov es:30h,ax quit_unlink: ret ;............................................................................... ; free_xms: ; frees XMS memory allocated by device driver ; Input: ; ES:SI - Device Header ;............................................................................... free_xms proc near push es push bx push si test flags,1 ;ICB found ? jz free_xms_end ;No,jump mov ax,es dec ax mov es,ax inc ax cmp byte ptr es:[si + 7],'X' jne free_xms_end cmp word ptr es:[si + 8],'SM' jne free_xms_end mov dx,es:[si + 0eh] ;get xms handle to DX les bx,dword ptr es:[si + 0ah] cmp byte ptr es:[bx],0eah ;jmp xxxx:yyyy ? jne free_handle cmp es:[bx + 3],ax ;jump into driver's segment ? jne free_handle cli mov word ptr es:[bx],3ebh ;place jmp short there mov word ptr es:[bx + 2],9090h mov byte ptr es:[bx + 4],90h sti free_handle: mov ax,4300h int 2fh cmp al,80h jne free_xms_end mov ax,4310h int 2fh mov xms_offs,bx mov xms_seg,es mov ah,0ah call dword ptr xms_offs free_xms_end: pop si pop bx pop es ret free_xms endp ;............................................................................... ; seek_stdin: ; seek Device Header of previous stdin device ; OUTPUT: ; AX:SI - points to Dev. Header of previous STDIN ; Carry Flag set if not found ;............................................................................... seek_stdin proc near stdin_next: les si,dword ptr es:[si] ;Address of next dev. header mov ax,es cmp ax,-1 jz stdin_err_end mov ax,es:dev_attr[si] test al,1 jz stdin_next mov ax,es clc ret stdin_err_end: stc ret seek_stdin endp ;............................................................................... ; seek_DIB: ; seek DIBs pointing at our Device Header and remove them from the ; chain of DIBS. ; INPUT: ; AX:DX - address of our Device Header ; OUTPUT: ; ES:BX - last DIB ; Carry Flag set if proper DIB not found ;............................................................................... seek_DIB proc near mov es,dos_seg les bx,es:FIRST_DIB ;Get address of first DIB mov si,dos_dep3 next_DIB: cmp word ptr es:[si + bx + 12h],dx jnz if_last cmp word ptr es:[si + bx + 14h],ax jz seek_end if_last: cmp word ptr es:[si + bx + 18h],0ffffh ;The last DIB ? jz seek_end2 ;Yes,jump mov DIB_offs,bx mov DIB_seg,es les bx,dword ptr es:[si + bx + 18h] ;Get addr. of next DIB jmp next_DIB seek_end: mov word ptr es:[si + bx + 14h],ZERO mov al,byte ptr es:[bx] ;Get drive number mov drv_num,al clc ret seek_end2: stc ret seek_DIB endp ;...............................................................................; ; get_DA_addr: ; compute address of Drive Area for drive AL ; INPUT: ; AL - drive number ; OUTPUT: ; ; ES:DI - address of Drive Area for drive AL ; ;...............................................................................; get_DA_addr proc near push ax push dx dec al xor ah,ah mov dl,51h ;Set DA ... add dl,dos_dep2 ; ... size mul dl ;Multiply by DA size mov es,dos_seg les di,dword ptr es:FIRST_DA ;Get addr. of first DA add di,ax ;So now ES:DI points to new DA pop dx pop ax ret get_DA_addr endp ;............................................................................... ; seek_DA: ; seek Drive Area for drv_num ; On input: ; SI:DX - DIB address ;............................................................................... seek_DA proc near mov es,dos_seg mov al,drv_num xor ch,ch mov ah,byte ptr es:TOTAL_NUM ;Get total number of drives check_next_DA: inc al cmp al,ah ja check_end call get_DA_addr ;Get address of DA to ES:DI cmp word ptr es:[di + 45h],dx ;DA not used ? jnz check_next_DA ;Yes,jump cmp word ptr es:[di + 47h],si ;DA jnz check_next_DA inc DA_flag mov word ptr es:[di + 43h],ZERO ;mark DA as not used push ax add al,40h mov byte ptr es:[di],al pop ax mov byte ptr es:[di + 3],ZERO jmp check_next_DA ret check_end: stc ;Signal error ret seek_DA endp code ENDS END start