Computer Select (Limited Edition)

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Assembly Source File | 1992-04-03 | 66.9 KB | 1,973 lines

page 66,132 ;============================================================================ ; DOSCLIP.COM impliments a DOS clipboard ; ; Usage: DOSCLIP [/B][/U] ; ; B = Use Video BIOS calls ; U = Uninstall ; ; Revision History: ; ; Version 1.0 Initial Release ; ;============================================================================ POPTIME equ 9 ;Allow 1/2 second to popup COPYTIME equ 180 ;Allow 10 seconds to copy STACKSIZE equ 512 ;TSR stack INSTDATASIZE equ offset DataBlockEnd - offset DataBlock MSGBOX_BUFFSIZE equ 1 * 132 * 2 ;Screen save buff for title HELPBOX_BUFFSIZE equ 5 * 132 * 2 ;Screen save buff for help RES_STACK equ offset end_of_resident + STACKSIZE MSGBOX_BUFFER equ offset end_of_resident + STACKSIZE ATTR_BUFFER equ MSGBOX_BUFFER + MSGBOX_BUFFSIZE ;---------------------------------------------------------------------------- ; BIOS Data segment ;---------------------------------------------------------------------------- bios_data segment at 40h org 17h shift_state db ? ;State of keyboard shift keys org 1Ah keybuff_head dw ? ;Start ptr for keyboard buff keybuff_tail dw ? ;End ptr for keyboard buff org 4Eh video_buffoff dw ? ;Offset of video buffer org 63h video_ioregs dw ? ;I/O addr of video controller org 80h keybuff_start dw ? ;Start ptr for keyboard buff keybuff_end dw ? ;End ptr for keyboard buff video_rows db ? ;Number of rows on the screen bios_data ends ;---------------------------------------------------------------------------- ; DOSCLIP Code and Data segments ;---------------------------------------------------------------------------- code segment assume cs:code org 2ch env_segment dw ? ;Word containing the segment ; of the program's env. block. org 80h command_tail db ? ;Offset of the command tail. org 100h prog: jmp initialize ;--------------------------------------------------------------------------- pushf ; Resident Data (Global to all sessions) ;--------------------------------------------------------------------------- pushf program db 13,10 program1 db "DOSCLIP 1.0 " copyright db "(c) 1992 Douglas Boling" program2 db 10,13 db "First published in PC Magazine, April 14, 1992" db 13,10,"$",1Ah def_marked_bw db 70h ;Default marked attr B/W def_text_bw db 70h ;Default text attr B/W bw_segment dw 0B000h ;Segment of B/W video memory def_marked_clr db 70h ;Default marked attr Color def_text_clr db 71h ;Default text attr Color clr_segment dw 0B800h ;Segment of color video memory attr_buffsize dw 1024 ;Size of attribute buffer helpbox_buff dw 0 ;Pointer to helpbox buffer copykey db 2eh ;Hotkey for copy command 'C' copyshift db 08h ;Shift for copy hotkey. 'Alt' pastekey db 2Fh ;Hotkey for paste command 'V' pasteshift db 08h ;Shift for paste hotkey. 'Alt' clipboard_buff dd 0 ;Pointer to clipboard buffer clipboard_size dw 4096 ;Max size of clipboard clipboard_dptr dd 0 ;Ptr data in clipboard clipboard_dsize dw 0 ;Size of data in clipboard win_enhanced db 0 ;Enhanced mode Windows active indos_ptr dd -1 ;Pointer to INDOS flag criterr_ptr dd -1 ;Pointer to DOS crit err flag int08h dd -1 ;Int 08 vector (Timer) int09h dd -1 ;Int 09 vector (Keyboard HW) int10h dd -1 ;Int 10 vector (Video BIOS) int13h dd -1 ;Int 13 vector (Disk BIOS) int16h dd -1 ;Int 16 vector (Keyboard) int28h dd -1 ;Int 28 vector (DOS Idle) int2Fh dd -1 ;Int 2F vector (DOS Multiplex) keycodes db 3bh,51h,49h,4fh,47h,48h,50h,74h,73h,4bh,4dh keycodes_end = $ keyjmp_table dw offset cursor_rt ;Index into key routines are dw offset cursor_lt ; inverse of order of dw offset cursor_clt ; keycode array. dw offset cursor_crt dw offset cursor_dn dw offset cursor_up dw offset cursor_home ;Home dw offset cursor_end ;End dw offset cursor_top ;Page Up dw offset cursor_bottom ;Page Down dw offset showhelp ;F1 helptag db "F1 for Help " helptag_end = $ db 0 ;Terminating 0 for helptag no_help db 0 ;Blocks help msg ; 1234567891123456789212345678931234567894 helpmsg1 db " <Cursor> keys delete box/move cursor " db " <Shift><Cursor> keys size box",0 helpmsg2 db " <Home> Move to start of line " db " <End> Move to end of line",0 helpmsg3 db " <Pg Up> Move to top of screen " db " <Pg Dn> Move to bot of screen",0 helpmsg4 db " <C> Copy box into clipboard " db " <V> Paste clipboard data",0 helpmsg5 db " <Esc> Exit the program",0 ; ;Screen variables ; BIOSFlag db 0 ;1 = Use Vid BIOS calls video_ptr label dword video_offset dw 0 ;Offset of video memory video_seg dw 0 ;Segment of video memory ; ;Switcher global data structures ; StartupInfo = $ sisVersion dw 3 ;Switcher structure ID sisNextDev dd 0 ;Ptr to prev startup structure sisVirtDevFile dd 0 ;Ptr to name of opt dev drvr sisReferenceData dd 0 ;Data for Win dev drivr sisInstData dd 0 ;Ptr to instance mem list DataBlockPtr dd 0 ;Ptr to instance data DataBlockSize dw 0 ;Size of instance data StackBlockPtr dd 0 ;Ptr to instance stack StackBlockSize dw 0 ;Size of instance stack dd 0 ;Ptr to next block = 0 to dw 0 ; terminate list ;============================================================================ ;Instance data ;============================================================================ DataBlock = $ ; ; Program Instance data ; hotshift db 0ah ;Shift condition for popup popflag db 0 ;Go active counter int08_active db 0 ;Interrupt active flag int09_active db 0 ;Interrupt active flag int10_active db 0 ;Interrupt active flag int13_active db 0 ;Interrupt active flag int28_active db 0 ;Interrupt active flag int2F_active db 0 ;Interrupt active flag main_active db 0 ;TSR active flag saved_ss dw 0 ;Saved forground stack ptr saved_sp dw 0 copy_flag db 0 ;Flag indicating copy to clip paste_flag db 0 ;Flag indicating paste marked_attr db 0 ;Screen attr for marked area text_attr db 0 ;Attribute for msg box text cursor_pos dw 0 ;Cursor position at popup cursor_type dw 0 ;Cursor shape at popup screen_page db 0 ;Active video page screen_size label word screen_cx db 0 ;Screen columns screen_cy db 0 ;Screen rows marked_pos1 label word marked_x1 db 0 ;Marked area starting column marked_y1 db 0 ;marked area starting row marked_pos2 label word marked_x2 db 0 ;Marked area ending column marked_y2 db 0 ;marked area ending row oldmarked_pos1 label word oldmarked_x1 db 0 ;Marked area starting row oldmarked_y1 db 0 ;marked area starting column oldmarked_pos2 label word oldmarked_x2 db 0 ;Marked area columns oldmarked_y2 db 0 ;marked area rows boxactive db 0 ;Flag for message box DataBlockEnd = $ ;============================================================================ ; VIDEOINT processes BIOS video services interrupt (Int 10h) ;============================================================================ videoint proc far assume cs:code,ds:nothing,es:nothing inc cs:int10_active pushf call cs:[int10h] ;Call old int dec cs:int10_active iret ;Return videoint endp ;============================================================================ ; DISKINT processes BIOS disk services interrupt (Int 13h) ;============================================================================ diskint proc far assume cs:code,ds:nothing,es:nothing inc cs:int13_active pushf call cs:[int13h] ;Call old int pushf dec cs:int13_active popf ret 2 ;Return preserving flags diskint endp ;============================================================================ ; TIMERINT processes timer interrupt (Int 08h) ;============================================================================ timerint proc far assume cs:code,ds:nothing,es:nothing pushf call cs:[int08h] ;Call old int 8 push ax push ds mov ax,cs mov ds,ax assume ds:code cmp int08_active,0 ;See if we are in this jne timerint_exit1 ; routine already inc int08_active ;Set int active flag cmp popflag,0 ;See if we need to try to jne timer_check ; pop up cmp paste_flag,1 ;See if there is data to je timer_paste_2 ; paste from clipboard ja timer_paste timerint_exit: dec int08_active ;Clear int active flag timerint_exit1: pop ds pop ax iret ;Return timer_check: call check_system ;See if system OK to pop up or ax,ax jne timerint_dec call main ;Call the TSR mov popflag,1 timerint_dec: dec popflag jmp short timerint_exit timer_paste_2: cmp paste_flag,1 ;See if there is data to jne timerint_exit ; paste call push_key jnc timer_paste_2 jmp short timerint_exit timer_paste: cmp win_enhanced,0 ;See if Win/386 active je timer_paste_1 call getwinclip ;Get data from the clipboard cmp ax,-1 ;If -1, can't open clipboard, je timerint_exit ; try again later. mov paste_flag,0 ;If 0, no data available. or ax,ax je timerint_exit mov clipboard_dsize,ax ;Else, AX = bytes mov ax,word ptr clipboard_buff ; read from CB. mov word ptr clipboard_dptr,ax mov paste_flag,1 jmp short timer_paste_2 timer_paste_1: mov paste_flag,0 ;If no Win/386, see if any cmp clipboard_dsize,0 ; data in the clipboard. je timerint_exit ; If not, cancel paste. mov paste_flag,1 jmp short timer_paste_2 timerint endp ;============================================================================ ; KEYINT processes keyboard interrupts (Int 09h) ;============================================================================ keyint proc far assume cs:code,ds:nothing,es:nothing push ax push ds mov ax,40h mov ds,ax ;Set ES to bios data segment assume ds:bios_data mov ah,ds:[shift_state] and ah,0fh ;Mask lock bits cmp ah,cs:[copyshift] je keyint_copy keyint_1: cmp ah,cs:[pasteshift] je keyint_paste keyint_jmp: pop ds pop ax jmp cs:[int09h] ;Call old int 9 keyint_exit: cli ;Disable interrupts in al,61h ;Reset the keyboard mov ah,al ; controller or al,80h out 61h,al mov al,ah out 61h,al mov al,20h ;Signal end-of-interrupt to out 20h,al ; the interrupt controller sti ;Enable interrupts pop ds pop ax iret keyint_copy: in al,60h ;Get scan code from keyboard cmp al,cs:copykey jne keyint_1 mov cs:popflag,POPTIME ;Set timer to pop up jmp short keyint_exit keyint_paste: in al,60h ;Get scan code from keyboard cmp al,cs:pastekey ;Compare to paste hotkey jne keyint_jmp mov cs:paste_flag,2 ;Set Paste flag jmp short keyint_exit keyint endp ;============================================================================ ; IDLEINT processes DOS Idle interrupt (Int 28h) ;============================================================================ idleint proc far assume cs:code,ds:nothing,es:nothing pushf call cs:[int28h] ;Call old int push ds push cs pop ds assume ds:code cmp int28_active,0 ;See if we are in this jne idleint_exit1 ; routine already inc int28_active ;Set int active flag cmp popflag,0 ;See if we need to try to jne idle_check ; pop up idleint_exit: dec int28_active ;Clear int active flag idleint_exit1: pop ds iret ;Return idle_check: push ax call check_system ;See if OK to pop up. Ignore or al,al ; INDOS since in idle. jne idleint_1 mov popflag,0 ;Clear popup flag call main ;Call the TSR idleint_1: pop ax jmp short idleint_exit idleint endp ;============================================================================ ; MUXINT processes DOS multiplex interrupt (Int 2Fh) ;============================================================================ muxint proc far assume cs:code,ds:nothing,es:nothing cmp ax,1605h ;See if Windows launch je mux_winstart cmp ax,1606h ;See if Windows terminate je mux_winend cmp ax,1608h ;See if Windows launch je mux_wingo ; complete cmp ax,4b05h ;See if switcher get instance je init_instance ; data. muxint_jmp: jmp cs:[int2Fh] ;Jump to old int mux_winend: test dx,01h ;See if enhanced mode Windows jne muxint_jmp dec cs:win_enhanced ;Clear Enhanced mode win flag jmp short muxint_jmp mux_wingo: cmp cs:clipboard_dsize,0 ;If Windows starts and we je muxint_jmp ; have data in our cmp cs:win_enhanced,0 ; clipboard, copy our je muxint_jmp ; data to the Win clipboard mov cs:copy_flag,COPYTIME jmp short muxint_jmp mux_winstart: test dx,01h ;See if enhanced mode Windows jne init_instance inc cs:win_enhanced init_instance: pushf call cs:[int2fh] ;Call old int mov word ptr cs:[sisNextDev],bx mov word ptr cs:[sisNextDev+2],es push cs ;ES:BX point to switcher struc pop es mov bx,offset StartupInfo jmp short muxint_exit muxint_exit: iret muxint endp ;--------------------------------------------------------------------------- pushf ; Check System Determines if the system is in a state compatible with TSRs ; Exit: AL - ORed flags for DOS Idle OK ; AH - State of INDOS flag ;--------------------------------------------------------------------------- pushf check_system proc near assume cs:code,ds:code,es:nothing push bx push ds xor ax,ax or al,int10_active ;Check BIOS video int or al,int13_active ;Check BIOS disk int lds bx,criterr_ptr ;Check DOS critical error or al,byte ptr ds:[bx] ; flag. lds bx,cs:indos_ptr ;Check INDOS flag mov ah,byte ptr ds:[bx] check_sys_exit: pop ds pop bx ret check_system endp ;----------------------------------------------------------------------------- ; GETWINCLIP Gets any data from the Windows Clipboard ; Exit AX - FF Can't open clipboard ; 0 Error in clipboard or clipboard data not available ; Else, number of bytes read from clipboard ;----------------------------------------------------------------------------- getwinclip proc near assume ds:code mov ax,1701h ;Open Clipboard int 2fh or ax,ax ;Error opening, exit mov ax,-1 je getwinclip_exit1 push bx push dx push es mov ax,1704h ;Get clipboard data size mov dx,7 ;Request OEM Text int 2fh or dx,dx ;See if too much data jne getwinclip_exit cmp ax,clipboard_size jbe getwinclip_1 xor ax,ax ;Indicate error jmp short getwinclip_exit getwinclip_1: cmp dx,ax ;If 0 size, no data in je getwinclip_exit ; correct format. push ax mov ax,1705h ;Get clipboard data les bx,clipboard_buff mov dx,7 ;Get OEM text int 2fh or ax,ax pop ax je getwinclip_exit dec ax getwinclip_exit: push ax mov ax,1708h ;Close Clipboard int 2fh pop ax pop es pop dx pop bx getwinclip_exit1: ret getwinclip endp ;----------------------------------------------------------------------------- ; GETCLIPSIZE Gets the size of the data in the Windows clipboard ;----------------------------------------------------------------------------- getclipsize proc near assume ds:code mov ax,1701h ;Open Clipboard int 2fh or ax,ax ;Error opening, exit je getclipsize_exit mov ax,1704h ;Get clipboard data size mov dx,7 ;Request OEM Text int 2fh mov ax,1708h ;Close Clipboard int 2fh pop es pop dx pop bx getclipsize_exit: ret getclipsize endp ;----------------------------------------------------------------------------- ; SETWINCLIP Sets the Windows clipboard ; Exit: ZF - Set if error ;----------------------------------------------------------------------------- setwinclip proc near assume ds:code push bx push cx push dx push si push es mov ax,1700h ;Check API int 2fh or ax,ax ;no API je setwinclip_exit1 mov ax,1701h ;Open Clipboard int 2fh or ax,ax ;Error opening, exit je setwinclip_exit1 mov ax,1702h ;Clear Clipboard int 2fh or ax,ax ;Error, exit je setwinclip_exit1 mov ax,1703h ;Set clipboard data les bx,clipboard_buff ;ES:BX ptr to data xor si,si ;SI,CX = data size mov cx,clipboard_dsize mov dx,7 ;Data format is OEM text int 2fh setwinclip_exit: mov ax,1708h ;Close Clipboard int 2fh or ax,ax ;Set ZF if error setwinclip_exit1: pop es pop si pop dx pop cx pop bx ret setwinclip endp ;----------------------------------------------------------------------------- ; INCKEYPTR Incriments the keyboard buffer pointer ; Entry: DI - Current Keyboard tail pointer ;----------------------------------------------------------------------------- inckeyptr proc near assume ds:bios_data inc di ;Make room in buffer inc di cmp di,ds:[keybuff_end] ;Get ptr to end of buffer jne inckeyptr_1 mov di,ds:[keybuff_start] ;Get ptr to buffer offset inckeyptr_1: ret inckeyptr endp ;----------------------------------------------------------------------------- ; PUSH KEY Fills the keyboard buffer with data from the clipboard. ; Exit: CF - Set if keyboard buffer full ; AX - modified ;----------------------------------------------------------------------------- push_key proc near assume ds:nothing,es:nothing push di push si push ds push es cli mov ax,bios_data mov ds,ax assume ds:bios_data cli ;No interrupts mov di,ds:[keybuff_tail] push di call inckeyptr cmp di,ds:[keybuff_head] ;See if buffer full pop di stc je push_key_exit les si,cs:[clipboard_dptr] ;Get ptr to clip data mov ax,word ptr cs:[clipboard_buff] add ax,cs:[clipboard_dsize] ;Add size of data cmp ax,si ;See if at end of buffer mov al,es:[si] ;Get clipboard byte jne push_key_2 ;No, continue mov cs:[paste_flag],0 ;Clear paste flag mov si,word ptr cs:[clipboard_buff] ;Reset data ptr dec si push_key_2: or al,al ;Don't stuff null char je push_key_3 cmp al,0ah ;Don't stuff line feeds je push_key_3 xor ah,ah ;Clear scan code cmp al,0dh ;If CR character, add proper jne push_key_21 ; scan code for Word Perfect mov ah,1ch push_key_21: mov ds:[di],ax ;Push data into keyboard buff call inckeyptr mov ds:[keybuff_tail],di ;Save keybuff ptr push_key_3: inc si ;Update clip data ptr mov word ptr cs:[clipboard_dptr],si ;Save clipdata ptr clc push_key_exit: sti ;Allow interrupts pop es pop ds pop si pop di ret push_key endp ;============================================================================ ; MAIN This routine does most of the work for the TSR ;============================================================================ main proc near assume cs:code,ds:code,es:nothing cmp main_active,0 ;See if already active jne main_exit cli inc main_active mov [saved_sp],sp ;Save old stack pointer mov [saved_ss],ss mov ax,cs ;Set ss:sp to internal stack mov ss,ax mov sp,RES_STACK sti ;Enable interrupts cld ;Set string direction UP push bx push cx push dx push di push si push bp push es mov ah,0fh ;Get display mode int 10h cmp al,7 je main_1 ;Pop up only if in text mode. cmp al,4 jb main_1 main_exit1: pop es pop bp pop si pop di pop dx pop cx pop bx cli mov ss,[saved_ss] ;Restore old stack mov sp,[saved_sp] dec main_active main_exit: ret main_1: xor dl,dl mov no_help,dl ;Enable help message mov copy_flag,dl ;Clear copy to clip flag cmp ah,80 jb main_exit1 mov screen_page,bh ;Save active video page mov screen_cx,ah ;Save screen columns mov ah,3 ;Get cursor position int 10h mov cursor_pos,dx ;Save cursor information mov cursor_type,cx cmp dh,0 ;If on top line, move down 1 jne main_11 ; to miss banner. inc dh main_11: mov marked_pos1,dx ;Save initial cursor position mov ax,40h mov es,ax ;Set ES to bios data segment assume es:bios_data mov ah,12h ;Determine if CGA by checking mov bl,10h ; for EGA compatibility int 10h mov al,24 ;CGA, only 25 rows on screen cmp bl,10h je main_2 mov al,es:video_rows ;Get number of rows on screen main_2: mov screen_cy,al ;Save screen rows mov ax,es:video_buffoff ;Copy ptr to video memory mov video_offset,ax mov ax,marked_pos1 ;Copy starting pos to ending mov marked_pos2,ax ; pos to zero block. mov oldmarked_pos1,ax mov oldmarked_pos2,ax test es:video_ioregs,40h ;See if color or monochrome jne main_colorvid mov si,offset def_marked_bw ;Point to B/W parameters jmp short main_3 main_colorvid: mov si,offset def_marked_clr ;Point to color parameters main_3: push ds pop es assume es:code mov di,offset marked_attr ;Copy default attributes movsw lodsw ;Get Video buffer segment mov video_seg,ax mov ah,1 ;Hide the cursor by changing mov cx,200h ; the size of the cursor int 10h call init_attrlist ;Initialize attr save list jc main_end1 mov dx,marked_pos1 ;Mark initial cursor where call getchar ; the old cursor was mov ah,marked_attr ;Mark cursor position on call putchar ; screen. main_loop: cmp boxactive,1 ;If box active, don't reprint je main_4 ; the box. mov al,marked_y2 ;If cursor on top line, don't or al,marked_y2 ; print the title box. je main_4 call msgbox ;Draw title box main_4: call getkey ;Wait for a key cmp al,27 ;If ESC, end. je main_end cmp ah,pastekey ;If 'v' paste and exit je main_paste cmp ah,28 ;If Enter, copy and exit je main_copy cmp ah,copykey ;If 'c' copy and exit je main_copy mov al,ah ;Copy scan code main_6: mov di,offset keycodes mov cx,offset keycodes_end - offset keycodes repne scasb jne main_loop shl cx,1 ;Convert key num into jump mov bx,cx ; table index. mov ax,marked_pos2 ;Preload parameters into regs mov cx,screen_size ; to save code call [keyjmp_table+bx] ;Call key routine jmp short main_loop main_copy: mov copy_flag,1 jmp short main_end main_paste: cmp win_enhanced,0 ;If enhanced mode Windows je main_paste_1 ; active, get clipboard call getwinclip ; data from the Windows jmp short main_end ; Clipboard. main_paste_1: cmp clipboard_dsize,0 ;If clipboard empty, don't je main_end ; paste. mov paste_flag,1 main_end: call clearmarked ;Restore attributes call clearbox ;Delete title box main_end1: mov ah,1 ;Set cursor type mov cx,cursor_type mov bh,screen_page int 10h mov ah,2 ;Set cursor position mov dx,cursor_pos int 10h jmp main_exit1 main endp ;----------------------------------------------------------------------------- ; CURSOR KEYS Handles the actions of the cursor keys as the user uses them ; to mark the selected area. ; Entry: AL - marked_x2 ; AH - marked_y2 ; CL - screen_cx ; CH - screen_cy ;----------------------------------------------------------------------------- cursor_keys proc near ; CURSOR HOME Moves the cursor to the left most column cursor_home: xor al,al ;Zero current column jmp short cursor_1 ; CURSOR END Moves the cursor to the right most column cursor_end: mov al,cl ;Set Cur column to screen cols dec al jmp short cursor_1 ; CURSOR TOP Moves the cursor to the top row cursor_top: mov ah,1 ;Move to line 1 to avoid jmp short cursor_1 ; title erase ; CURSOR END Moves the cursor to the bottom row cursor_bottom: mov ah,ch ;Set Cur Row to screen rows jmp short cursor_1 ; CURSOR UP Moves the marked orgin up one row cursor_up: or ah,ah je cursor_1 dec ah jmp short cursor_1 ; CURSOR DN Moves the marked orgin down one row cursor_dn: cmp ah,ch je cursor_1 inc ah jmp short cursor_1 ; CURSOR CLT Moves the marked orgin left 8 columns cursor_clt: sub al,8 jae cursor_1 xor al,al jmp short cursor_1 ; CURSOR CRT Moves the marked orgin right 8 columns cursor_crt: add al,8 dec cl cmp al,cl jb cursor_1 mov al,cl jmp short cursor_1 ; CURSOR LT Moves the marked orgin left one col cursor_lt: or al,al je cursor_1 dec al jmp short cursor_1 ; CURSOR RT Moves the marked orgin right one col cursor_rt: dec cl cmp al,cl jae cursor_1 inc al cursor_1: mov marked_pos2,ax ;Save new position push ax mov ah,2 ;Get shift state int 16h and al,3 pop ax jne cursor_2 mov marked_pos1,ax ;Not shifted, set points equal cursor_2: or ah,ah ;If cursor on top line, clear jne cursor_3 ; title box so user can see call clearbox ; what is on top line. cursor_3: call drawmarked ret cursor_keys endp ;----------------------------------------------------------------------------- ; DRAWMARKED Displays the marked area by changing the screen attributes ; inside the marked area. ;----------------------------------------------------------------------------- drawmarked proc near push es mov ax,marked_pos1 mov dx,marked_pos2 cmp dx,oldmarked_pos2 jne drawmarked_1 cmp ax,oldmarked_pos1 je drawmarked_exit drawmarked_1: mov bx,offset marked_pos1 mov cx,4 drawmarked_2: call find_min ;AX = upper left corner call find_max ;DX = lower right corner add bx,2 loop drawmarked_2 drawmarked_7: sub dx,ax ;Compute size of area xor cx,cx mov cl,dl ;Copy column count mov si,cx inc si mov cl,dh ;Copy row count inc cx mov dx,ax ;Copy starting row, column drawmarked_8: push cx ;Save row count push dx ;Save cursor position mov cx,si ;Get column count drawmarked_9: mov bx,offset marked_pos1 call chk_inwin mov ah,al ;Save in marked area flag mov bx,offset oldmarked_pos1 call chk_inwin cmp ah,al ;See if in or out of both je drawmarked_11 ; areas. If so, no change. push ax ;Save in-window flags call getchar pop bx or bh,bh ;See if in marked area je drawmarked_10 mov ah,marked_attr ;Mark character call putchar jmp short drawmarked_11 drawmarked_10: call get_attr ;Get saved screen attribute call putchar ;Restore attribute drawmarked_11: inc dl loop drawmarked_9 pop dx pop cx inc dh loop drawmarked_8 mov ax,marked_pos1 ;Update old pointers mov oldmarked_pos1,ax mov ax,marked_pos2 mov oldmarked_pos2,ax drawmarked_exit: pop es ret drawmarked endp ;----------------------------------------------------------------------------- ; CLEARMARKED Restores the marked area to its original screen attributes ;----------------------------------------------------------------------------- clearmarked proc near assume ds:code push es mov bx,offset marked_pos1 call compute_box sub ax,dx xor cx,cx mov cl,al mov si,cx ;Save column count inc si mov cl,ah inc cx xor bx,bx cmp copy_flag,0 je clearmarked_3 mov bx,clipboard_size les di,clipboard_buff mov word ptr [clipboard_dptr],di clearmarked_3: push cx push dx mov cx,si ;Get row count clearmarked_4: call getchar or bx,bx ;If copying data to je clearmarked_5 ; clipboard, save char. stosb dec bx clearmarked_5: call get_attr ;Get saved screen attribute call putchar inc dl loop clearmarked_4 or bx,bx je clearmarked_6 mov ax,0a0dh ;Append CR-LF to line stosw dec bx dec bx clearmarked_6: pop dx pop cx inc dh loop clearmarked_3 cmp copy_flag,0 je clearmarked_exit xor al,al stosb dec bx sub bx,clipboard_size not bx mov clipboard_dsize,bx mov ax,word ptr cs:[clipboard_buff] mov word ptr cs:[clipboard_dptr],ax cmp win_enhanced,0 ;If enhanced mode Windows je clearmarked_exit ; active, save data to call setwinclip ; Windows clipboard clearmarked_exit: pop es ret clearmarked endp ;----------------------------------------------------------------------------- ; GET ATTR Gets a saved attribute in the attribute buffer for a given ; cursor location. ; Entry: DX - Row, Column of character ; Exit: AH - Attribute ;----------------------------------------------------------------------------- get_attr proc near push cx push dx push si push ax call compute_offset ;Get count into buffer mov si,ATTR_BUFFER xor ax,ax mov dx,ax get_attr_1: lodsb ;Get count byte inc si or al,al je get_attr_exit sub cx,ax jae get_attr_1 mov dh,[si-1] ;Get attribute get_attr_exit: pop ax mov ah,dh ;Copy attribute pop si pop dx pop cx ret get_attr endp ;----------------------------------------------------------------------------- ; INIT ATTRLIST Initializes the attribute list ;----------------------------------------------------------------------------- init_attrlist proc near assume ds:code mov bx,screen_size ;Get size of screen inc bh inc bh xor ax,ax mov dx,ax ;Start at top left corner mov cx,ax xchg bh,cl ;CX-Col count, BX-Row cnt mov si,bx mov di,ATTR_BUFFER ;Get pointer to buffer call getchar mov bh,ah mov bl,0 init_attrlist_1: push cx push dx mov cx,si ;Get number of columns init_attrlist_2: call getchar ;Read attribute cmp bh,ah ;Compare attributes jne init_attrlist_newblk ;If different write block inc bl ;Incriment count cmp bl,-1 ;If count full, write block je init_attrlist_newblk mov bh,ah ;Copy attribute value init_attrlist_3: inc dl ;Next column loop init_attrlist_2 pop dx pop cx inc dh ;Next row loop init_attrlist_1 clc init_attrlist_exit: ret init_attrlist_newblk: mov ds:[di],bx ;Write old block to list inc di ;Update ptr inc di mov bl,1 ;New count mov bh,ah ;Copy new attribute cmp di,helpbox_buff jb init_attrlist_3 ;If list runs into the help inc no_help ; buffer, disable help push ax mov ax,helpbox_buff ;If past helpbox buffer, exit add ax,HELPBOX_BUFFSIZE cmp di,ax pop ax jb init_attrlist_3 ;If list past help box stc ; buffer, exit prog. jmp short init_attrlist_exit init_attrlist endp ;----------------------------------------------------------------------------- ; COMPUTE OFFSET Computes the offset into the attribute buffer for a ; given cursor location. ; Entry: DX - Row, Column of character ; Exit: CX - Offset in buffer. ;----------------------------------------------------------------------------- compute_offset proc near push ax push dx mov al,dh ;Copy column mul screen_cx ;Mul by width of screen xor dh,dh add ax,dx ;Add row xchg cx,ax pop dx pop ax ret compute_offset endp ;----------------------------------------------------------------------------- ; CHK INWIN Determines if a character is inside the bounds of an area ; Entry: BX - Pointer to bounding rectangle ; x1 db point 1 column ; y1 db point 1 row ; x2 db point 2 column ; y2 db point 2 row ; DX - Row, Column of character ; Exit: AL - <> 0 if inside area ;----------------------------------------------------------------------------- chk_inwin proc near push bx push cx push ax ;Save AX push dx ;Save current cursor pos call compute_box ;DX = UL corner, AX = LR corner pop bx xchg bx,dx ;DX = cur cursor, BX=UL corner mov cx,ax ;CX = LR corner pop ax ;Restore AX mov al,0 ;Clear inbox flag cmp dl,bl ;See if above starting row jb chk_inwin_exit cmp dh,bh ;See if left of starting col jb chk_inwin_exit cmp dl,cl ;See if below ending row ja chk_inwin_exit cmp dh,ch ;See if right of ending col ja chk_inwin_exit inc al chk_inwin_exit: pop cx pop bx ret chk_inwin endp ;----------------------------------------------------------------------------- ; FIND MIN Computes the smaller of two screen coordinates. ; Entry: AX - Row, Column of 1st coordinate ; BX - Pointer to 2nd coordinate ; Exit: AX - Result coordinate. ;----------------------------------------------------------------------------- find_min proc near cmp al,[bx] jbe find_min_1 mov al,[bx] find_min_1: cmp ah,[bx+1] jbe find_min_2 mov ah,[bx+1] find_min_2: ret find_min endp ;----------------------------------------------------------------------------- ; FIND MAX Computes the larger of two screen coordinates. ; Entry: DX - Row, Column of 1st coordinate ; BX - Pointer to 2nd coordinate ; Exit: AX - Result coordinate. ;----------------------------------------------------------------------------- find_max proc near cmp dl,[bx] jae find_max_1 mov dl,[bx] find_max_1: cmp dh,[bx+1] jae find_max_2 mov dh,[bx+1] find_max_2: ret find_max endp ;----------------------------------------------------------------------------- ; COMPUTE BOX Puts the starting row/column in DX and the SI and CX ; Entry: BX - Pointer to coordinates ; Exit: AX - Ending row/column ; DX - Starting row/column ;----------------------------------------------------------------------------- compute_box proc near mov ax,[bx] mov dx,[bx+2] cmp al,dl ja compute_box_1 xchg al,dl compute_box_1: cmp ah,dh ja compute_box_2 xchg ah,dh compute_box_2: ret compute_box endp ;----------------------------------------------------------------------------- ; SHOWHELP Displays a help screen on the first three lines of the display ;----------------------------------------------------------------------------- showhelp proc near cmp byte ptr no_help,0 ;See if help msg disabled. jne showhelp_exit mov dh,1 ;Box at top of screen mov cx,5 mov di,helpbox_buff showhelp_1: push cx call saveline inc dh pop cx loop showhelp_1 mov dh,1 mov si,offset helpmsg1 ;Write help text line call writeline inc dh ;Move to next line mov si,offset helpmsg2 call writeline inc dh ;Move to next line mov si,offset helpmsg3 call writeline inc dh ;Move to next line mov si,offset helpmsg4 call writeline inc dh ;Move to next line mov si,offset helpmsg5 call writeline call getkey ;Wait for a key mov dh,1 ;Box at top of screen mov cx,5 mov si,helpbox_buff showhelp_2: push cx call restoreline inc dh pop cx loop showhelp_2 showhelp_exit: ret showhelp endp ;----------------------------------------------------------------------------- ; MSGBOX displays a message in a text window on the top line of the ; screen. The current data on the screen is saved. ;----------------------------------------------------------------------------- msgbox proc near mov dh,0 ;Box at top of screen mov al,boxactive cmp al,2 ;Display sum only je msgbox_1 or al,al ;If box already displayed, jne msgbox_1 ; don't save screen data. mov di,MSGBOX_BUFFER call saveline msgbox_1: mov si,offset program1 mov cx,offset program2 - offset program1 xor dx,dx msgbox_11: lodsb call writechar loop msgbox_11 xor cx,cx mov cl,screen_cx sub cl,offset helptag_end - offset helptag ja msgbox_2 mov cl,screen_cx inc ch msgbox_2: push dx msgbox_3: mov al,' ' ;Pad line with spaces call writechar cmp dl,cl jb msgbox_3 or ch,ch jne msgbox_5 msgbox_4: mov si,offset helptag call writestr msgbox_5: pop dx mov boxactive,1 ;Set box active flag ret msgbox endp ;----------------------------------------------------------------------------- ; CLEARBOX removes the title box from the screen. ;----------------------------------------------------------------------------- clearbox proc near cmp boxactive,0 ;If box already displayed, je clearbox_2 ; don't save screen data. mov si,MSGBOX_BUFFER mov dh,0 ;Box at top of screen call restoreline mov boxactive,0 ;Clear box displayed flag clearbox_2: ret clearbox endp ;----------------------------------------------------------------------------- ; WRITELINE Writes a line of help text to the screen. The line is padded ; with spaces to the right. ; Entry: DH - Line on screen to write ; SI - Pointer to ASCIIZ text ;----------------------------------------------------------------------------- writeline proc near push dx xor dl,dl ;Start at left side of screen call writestr ;Write string writeline_2: mov al,' ' ;Pad line with spaces call writechar cmp dl,screen_cx jb writeline_2 pop dx ret writeline endp ;----------------------------------------------------------------------------- ; SAVELINE Saves the contents of a screen line ot a buffer ; Entry: DH - Line on screen to save ; DI - Pointer to save buffer ;----------------------------------------------------------------------------- saveline proc near push dx xor dl,dl ;Start at left side of screen xor cx,cx mov cl,screen_cx saveline_1: call getchar ;Read character from screen stosw inc dl ;Point to next character loop saveline_1 pop dx ret saveline endp ;----------------------------------------------------------------------------- ; RESTORELINE Restores the screen that was covered by a line of program ; helptext. ; Entry: DH - Line on screen to restore ; SI - Pointer to buffer that contains original screen contents ;----------------------------------------------------------------------------- restoreline proc near push dx xor dl,dl ;Start at left side of screen xor cx,cx mov cl,screen_cx restoreline_1: lodsw call writechar1 ;Read character from screen loop restoreline_1 pop dx ret restoreline endp ;----------------------------------------------------------------------------- ; WRITESTR Writes a string to the screen. ; Entry: DH,DL - Row/Column to write the string ; SI - Pointer to ASCIIZ text ;----------------------------------------------------------------------------- writestr proc near mov ah,text_attr writestr1: lodsb ;Read text from string, then or al,al ; call putchar to write to je writestr_1 ; the screen. call writechar1 jmp short writestr1 writestr_1: ret writestr endp ;----------------------------------------------------------------------------- ; WRITECHAR Writes a character to the screen ; Entry: AL - Character ; DX - Row, Column ;----------------------------------------------------------------------------- writechar proc near mov ah,text_attr writechar1: call putchar inc dl ret writechar endp ;----------------------------------------------------------------------------- ; GETCHAR Reads a character and its attribute from the screen ; Entry: DH - Row of character to read ; DL - Column of character to read ; Exit: AL - Character ; AH - Attribute ;----------------------------------------------------------------------------- getchar proc near push bx cmp BIOSFlag,0 jne getchar_bios push cx push si push ds call compute_offset ;Get offset into buffer shl cx,1 ;Double for char and attr lds si,video_ptr ;Get ptr to video memory add si,cx ;Double since char and attr lodsw ;Read char/attribute pop ds pop si pop cx jmp short getchar_exit getchar_bios: mov ah,2 ;Set cursor mov bh,screen_page int 10h mov ah,8 ;Read character/attr int 10h getchar_exit: pop bx ret getchar endp ;----------------------------------------------------------------------------- ; PUTCHAR Writes a character and its attribute to the screen ; Entry: AL - Character to write ; AH - Attribute to write ; DH - Row of character to write ; DL - Column of character to write ;----------------------------------------------------------------------------- putchar proc near push bx push cx push ax cmp BIOSFlag,0 jne putchar_bios push di push es call compute_offset ;Get offset into buffer shl cx,1 ;Double since char and attr les di,video_ptr add di,cx ;Add to start of buffer stosw ;Read char/attribute pop es pop di jmp short putchar_exit putchar_bios: mov ah,2 ;Set cursor mov bh,screen_page int 10h pop ax push ax mov bl,ah ;Copy attribute mov ah,9 ;Read character/attr mov cx,1 int 10h putchar_exit: pop ax pop cx pop bx ret putchar endp ;----------------------------------------------------------------------------- ; GETKEY Waits for a key from the keyboard. ; Exit: AX - Scan code, ASCII char from keyboard. ;----------------------------------------------------------------------------- getkey proc near mov ah,1 ;Check for key int 16h jnz getkey_exit int 28h ;Call DOS Idle mov ax,1680h ;Release Timeslice int 2fh jmp short getkey getkey_exit: xor ax,ax ;Get key int 16h ret getkey endp align 16 end_of_resident = $ ;---------------------------------------------------------------------------- ; Non-resident data. ;---------------------------------------------------------------------------- alrdy_installed db 0 ;Installed flag installed_seg dw 0 ;Segment of installed code dos_version dw 0 ;DOS version infomsg2 db "DOSCLIP uninstalled$" errmsg0 db "Need DOS 3.0 or greater$" errmsg1 db "DOSCLIP not installed$" errmsg2 db "Usage: DOSCLIP [/B][/U]",13,10 db "/B = Use Video BIOS",13,10 db "/U = Uninstall",13,10,"$" errmsg3 db "Can",39,"t uninstall$" errmsg4 db "DOSCLIP already installed$" errmsg5 db "Can not find Critical error flag$" endmsg db 13,10,"$" infomsg1 db "DOSCLIP installed",13,10,10 db "Copy key is " db "Alt C",13,10 db "Paste key is " db "Alt V","$" ;---------------------------------------------------------------------------- ; Initialization routine. ;---------------------------------------------------------------------------- initialize proc near assume cs:code,ds:code,es:code cld mov dx,offset program ;Print copyright message call printmsgcr mov ah,30h ;Get DOS version int 21h xchg al,ah ;Swap major, minor numbers mov dx,offset errmsg0 ;Bad DOS version cmp ah,3 ;Run if DOS 3.0 or greater. jb disp_error mov dos_version,ax ;Save version number mov ax,offset end_of_code+512 ;Set stack ptr mov sp,ax add ax,15 mov cl,4 ;Convert offset to segment size shr ax,cl mov ah,4ah ;Reduce memory allocation int 21h call find_installed ;See if already installed jc init_1 inc alrdy_installed ;Yes, set flag mov installed_seg,es ;Save seg of installed code init_1: push ds pop es mov dx,offset errmsg4 ;Default message mov di,80h ;Parse command line xor cx,cx or cl,[di] ;Get length of cmd line je init_exit init_2: mov al,'/' repne scasb ;Find command line switches jne init_exit mov al,[di] ;Get comamnd line switch or al,20h cmp al,'b' ;See if Video BIOS parameter jne init_3 inc BIOSFlag jmp short init_2 init_3: cmp al,'u' ;See if uninstall je init_4 mov dx,offset errmsg2 ;Print useage statement ; ;Display error message. ; assume ds:nothing disp_error: push cs pop ds assume ds:code call printmsgcr ;print string mov ax,4c01h ;Terminate with RC = 1 int 21h init_4: call remove ;Remove installed copy jc disp_error jmp short exit init_exit: cmp alrdy_installed,0 jne disp_error call install jc disp_error exit: mov ax,4C00h ;Terminate with RC = 0 int 21h initialize endp ;----------------------------------------------------------------------------- ; INSTALL Installs the program ;----------------------------------------------------------------------------- assume cs:code,ds:code,es:code install proc near mov ah,34h ;Get ptr to INDOS flag int 21h mov word ptr indos_ptr,bx mov word ptr indos_ptr[2],es call findCEF ;Get ptr to crit error flag jnc install_1 jmp install_error install_1: ; ;Set interrupt vectors ; mov word ptr criterr_ptr,bx mov word ptr criterr_ptr[2],es mov al,08h ;Get/set the timer interrupt mov dx,offset timerint mov di,offset int08h call set_interrupt mov al,09h ;Get/set the keyboard int mov dx,offset keyint mov di,offset int09h call set_interrupt mov al,10h ;Get/set the video interrupt mov dx,offset videoint mov di,offset int10h call set_interrupt mov al,13h ;Get/set the disk interrupt mov dx,offset diskint mov di,offset int13h call set_interrupt mov al,28h ;Get/set the DOS idle int mov dx,offset idleint mov di,offset int28h call set_interrupt mov al,2Fh ;Get/set the DOS Multiplex mov dx,offset muxint mov di,offset int2Fh call set_interrupt push cs push cs pop ds assume ds:code pop es assume es:code mov dx,offset infomsg1 ;Print program installed msg call printmsgcr ; ;Init buffer pointers. ; mov dx,ATTR_BUFFER ;Set pointers for resident add dx,attr_buffsize ; code. mov helpbox_buff,dx add dx,HELPBOX_BUFFSIZE ; ;Init clipboard pointers. ; mov word ptr [clipboard_buff],dx mov bx,dx ;Save size of save data area add dx,clipboard_size ;Add size of clipboard mov ax,cs mov word ptr [clipboard_buff+2],ax mov word ptr [clipboard_dptr+2],ax mov word ptr [clipboard_dsize],0 mov paste_flag,0 ; ;Init switcher structures ; mov word ptr [DataBlockPtr+2],ax mov word ptr [DataBlockPtr],offset DataBlock mov word ptr [DataBlockSize],INSTDATASIZE mov word ptr [StackBlockPtr+2],ax mov word ptr [StackBlockPtr],offset end_of_resident sub bx,offset end_of_resident ;Compute size of mov word ptr [StackBlockSize],bx ; Data save area mov word ptr [sisInstData+2],ax mov ax,offset DataBlockPtr mov word ptr [sisInstData],ax push dx ;Save Ptr to end of resident mov ax,1600h ;See if Enhanced mode windows int 2fh or al,al je nowin inc win_enhanced ;Set enhanced mode flag nowin: pop dx ;Get Ptr to end of resident add dx,15 mov cl,4 shr dx,cl mov ax,3100h ;Terminate and stay resident int 21h install_error: ret install endp ;----------------------------------------------------------------------------- ; REMOVE uninstalls the installed program from memory. ;----------------------------------------------------------------------------- remove proc near assume ds:code,es:code push ds push es mov ds,installed_seg ;Point DS to installed code assume ds:nothing mov dx,offset errmsg1 ;Not installed message cmp alrdy_installed,0 je remove_error1 mov al,8 ;Restore int 8 (Timer) mov dx,offset timerint mov di,offset int08h call restore_int jc remove_error mov al,9 ;Restore int 9 (keyboard) mov dx,offset keyint mov di,offset int09h call restore_int jc remove_error mov al,10h ;Restore int 10h (BIOS Video) mov dx,offset videoint mov di,offset int10h call restore_int jc remove_error mov al,13h ;Restore int 13h (BIOS disk) mov dx,offset diskint mov di,offset int13h call restore_int jc remove_error mov al,28h ;Restore int 28h (DOS Idle) mov dx,offset idleint mov di,offset int28h call restore_int jc remove_error mov al,2Fh ;Restore int 2Fh (DOS Mux) mov dx,offset muxint mov di,offset int2Fh call restore_int jc remove_error mov es,ds:[2ch] ;Get installed env seg mov ah,49h int 21h ;Free installed env segment push ds pop es mov ah,49h ;Free installed program segment int 21h mov ax,cs mov ds,ax mov es,ax mov dx,offset infomsg2 ;Print program removed msg call printmsgcr clc remove_exit: pop ds pop es ret remove_error: mov dx,offset errmsg3 ;Can't uninstall msg remove_error1: stc jmp short remove_exit remove endp ;----------------------------------------------------------------------------- ; SETINTERRUPT Get and sets an interrupt ; Entry: AL - Interrupt number ; DX - Pointer to new interrupt routine ; DI - Pointer to storage location for old interrupt vector ;----------------------------------------------------------------------------- assume cs:code,ds:code,es:nothing set_interrupt proc near push es push ax mov ah,35h ;DOS get interrupt int 21h pop ax mov word ptr [di],bx ;Save old vector mov word ptr [di+2],es mov ah,25h ;DOS set interrupt int 21h pop es ret set_interrupt endp ;----------------------------------------------------------------------------- ; RESTOREINT Checks to see if an interrupt vector has been changed, if not ; the interrupt vector is restored with its original value ; Entry: AL - Interrupt number ; DS:DX - Pointer to current interrupt routine ; DS:DI - Pointer to old interrupt vector ;----------------------------------------------------------------------------- assume cs:code,ds:nothing restore_int proc near push es push ax mov ah,35h ;DOS get interrupt int 21h pop ax ;Get back interrupt number cmp dx,bx ;Compare routine offset jne restoreint_error mov bx,es ;Get current vector segment mov cx,ds ;Get installed segment cmp cx,bx ;Compare routine segment jne restoreint_error push ds lds dx,ds:[di] ;Get old vector mov ah,25h ;DOS set interrupt int 21h clc pop ds restoreint_exit: pop es ret restoreint_error: stc jmp short restoreint_exit restore_int endp ;----------------------------------------------------------------------------- ; FINDCEF Finds the DOS ErrorMode (Critical error) flag ; Exit: ES:BX - Segment,offset of ErrorMode flag ; CF - Clear if flag found ;----------------------------------------------------------------------------- findCEF proc near mov ah,34h ;Get InDOS address int 21h dec bx cmp dos_version,30ah ;If DOS 3.1 or later, ErrorMode jnc findCEF_exit ; sits before InDOS. mov ax,3e80h ;CMP opcode mov si,028cdh ;Int 28 Opcode mov dl,75h ;JNE Opcode mov cx,-1 ;max search length mov di,bx ;start at INDOS address findCEF_1: repne scasb ;do the search jcxz findCEF_notfound ;branch if search failed cmp es:[di],ah ;Check other half of CMP opcode jne findCEF_1 cmp byte ptr es:[di+4],dl ;Check for JNE jne findCEF_1 cmp word ptr es:[di+6],si ; Check for Int 28h call jne findCEF_1 ;Resume loop if not found inc di mov bx,es:[di] ;Get offset of ErrorMode flag clc findCEF_exit: ret findCEF_notfound: stc mov dx,offset errmsg5 ;Can't find Critical Error flg jmp short findCEF_exit findCEF endp ;----------------------------------------------------------------------------- ; FIND INSTALLED Find the installed code by scanning the memory control blocks. ; Exit: AX - Segment of installed code if found. ; CF - Clear if installed code found ;----------------------------------------------------------------------------- find_installed proc near assume ds:code,es:code mov word ptr prog,0 mov bx,0A000h ;Start at upper mem blk start mov ax,cs ;keep CS value in AX find_installed_1: inc bx ;increment search segment value mov es,bx assume es:nothing cmp ax,bx ;not installed if current je find_installed_2 ; segment is found. call cmpheader jne find_installed_1 ;loop back if not found clc find_installed_exit: ret find_installed_2: stc jmp short find_installed_exit find_installed endp ;----------------------------------------------------------------------------- ; CMPHEADER compares the first 16 bytes of this file with the segment ; pointed to by ES. ; Entry: DS - code segment ; ES - pointer to segment to compare ; Exit: ZF - 0 = segments match. ;----------------------------------------------------------------------------- cmpheader proc near assume ds:code,es:nothing mov si,offset prog ;Search this segment for ASCII mov di,si ; fingerprint. mov cx,16 repe cmpsb ret cmpheader endp ;----------------------------------------------------------------------------- ; PRINTMSG prints the message pointed to by DX to the screen. ; Entry: DX - pointer to ASCII message terminated by $ ;----------------------------------------------------------------------------- printmsg proc near assume ds:nothing,es:nothing push ds push cs pop ds assume ds:code mov ah,9 ;Print message int 21h pop ds ret printmsg endp ;----------------------------------------------------------------------------- ; PRINTMSGCR calls PRINTMSG, then appends a carriage return to the message. ; Entry: DX - pointer to ASCII message terminated by $ ;----------------------------------------------------------------------------- printmsgcr proc near assume ds:nothing,es:nothing push dx call printmsg mov dx,offset endmsg call printmsg pop dx ret printmsgcr endp even end_of_code = $ code ends end prog