Category : Files from Magazines
Archive   : VOL8N11.ZIP
Filename : COLOR.ASM

;; COLOR uses the OS/2 ANSI driver to set screen foreground and background
;; colors in protected mode. Syntax is:
;;
;; COLOR fb
;;
;; where f = foreground color (X,x,B,b,G,g,C,c,R,r,M,m,Y,y,W,w), and
;; b = background color (x,b,g,c,r,m,y,w)
;;
;; Assemble with: MASM COLOR;
;; Link with: LINK COLOR,,NUL,DOSCALLS,COLOR;
;;
;; Module Definition File (COLOR.DEF):
;; NAME COLOR
;; STACKSIZE 4096
;; PROTMODE
;;
;; Copyright (c) 1989 Ziff Communications Co.
;; Written March 1989 for PC Magazine by Jeff Prosise

.286

extrn DosExit:far
extrn VioSetAnsi:far
extrn VioWrtTTY:far

DGROUP group _DATA

_DATA segment word public 'DATA'

ErrTxt1 db "Usage: COLOR fb",13,10
TxtLen1 equ $ - ErrTxt1

ErrTxt2 db "Invalid color ID",13,10
TxtLen2 equ $ - ErrTxt2

EscSeq db 27,"[0;",8 dup (?)
EscLen dw 4

FCodes db "XBGCRMYW"
BCodes db "xbgcrmyw"

FAnsiCodes db "37; 33; 35; 31; 36; 32; 34; 30;"
BAnsiCodes db "47m 43m 45m 41m 46m 42m 44m 40m"

_DATA ends

_TEXT segment word public 'CODE'
assume cs:_TEXT, ds:DGROUP
;;
;; MAIN is the main body of the program.
;;
main proc far

mov es,ax ;move env selector into ES
mov di,bx ;point DI to command line
cld ;clear direction flag
xor al,al ;find first null byte
repne scasb

next_char: cmp byte ptr es:[di],20h ;skip leading spaces
jne get_entry
inc di
jmp next_char
;
;Build the foreground portion of the ANSI escape string.
;
get_entry: mov al,es:[di] ;get foreground ID code
or al,al ;see if a foreground code
jnz check_next ; was entered

error1: push ds ;display error message
push offset DGROUP:ErrTxt1 ; and exit if not
push TxtLen1
error2: push 0
call VioWrtTTY

push 1 ;exit with return code of 1
push 1
call DosExit

check_next: mov ah,es:[di+1] ;get background ID code
or ah,ah ;exit if no background code
jz error1 ; was entered

mov bx,DGROUP ;point ES to DGROUP
mov es,bx
mov di,offset DGROUP:FCodes ;point DI to list of valid
mov cx,16 ; codes and see if the
repne scasb ; foreground entry is
je char_found ; valid

error3: push ds ;error if foreground entry
push offset DGROUP:ErrTxT2 ; isn't in the list
push TxtLen2
jmp error2

char_found: cmp cx,8 ;check for highlighted
jb normal ; foreground code

sub cx,8 ;add "1;" to ANSI string
mov EscSeq[4],"1" ; if foreground color
mov EscSeq[5],";" ; is highlighted
add EscLen,2

normal: mov si,offset DGROUP:FAnsiCodes ;append foreground
call append ; code to string
;
;Build the background portion of the ANSI escape string.
;
xchg ah,al ;transfer code to AL
mov di,offset DGROUP:BCodes ;check background entry
mov cx,8 ; for validity
repne scasb
jne error3

mov si,offset DGROUP:BAnsiCodes ;append background
call append ; code to string
;
;Activate the ANSI driver and send escape string to set colors.
;
push 1 ;enable the ANSI driver
push 0
call VioSetAnsi

push ds ;transmit the ANSI escape
push offset DGROUP:EscSeq ; sequence thru VioWrtTTY
push EscLen
push 0
call VioWrtTTY

push 1 ;exit program with return
push 0 ; code of 0
call DosExit

main endp
;;
;; APPEND appends a 3-character string to the ANSI escape string.
;;
append proc near

shl cx,2 ;multiply index by 4
add si,cx ;add to absolute offset
mov di,offset DGROUP:EscSeq ;point DI to end of
add di,EscLen ; ANSI string
mov cx,3 ;append 3 bytes
rep movsb
add EscLen,3 ;update pointer
ret

append endp

_TEXT ends

end main