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.286

. model tiny

. code

org 100h

start:

jmp begin

old_21h dd 0

flag db 0

log_file db 'c: \temp\filelist. log',0

filename db 200 dup (0)

data_str db '00-00-00 00: 00: 00 - '

eoln db 10,13

extensions db 100*3 dup (0)

fileerror db 'FILELIST. DAT Error! ',10,13,'$'

datname db 'filelist. dat',0

a_load db 'Program is in memory already!!! ',10,13,'$'

check_extension proc

mov di,offset filename-1

di_i:

inc di

mov al,byte ptr [di]

cmp al,0

jne di_i

sub di,3

mov ah,byte ptr [di]

mov bh,byte ptr [di+1]

mov ch,byte ptr [di+2]

mov si,offset extensions

new_name:

mov al,byte ptr [si]

mov bl,byte ptr [si+1]

mov cl,byte ptr [si+2]

cmp al,0

je exit_1

cmp bl,0

je exit_1

cmp cl,0

je exit_1

sub al,ah

sub bl,bh

sub cl,ch

add al,bl

add al,cl

cmp al,0

je exit_2

add si,3

jmp new_name

exit_1:

mov al,0

jmp exit_0

exit_2:

mov al,1

exit_0:

ret

check_extension endp

process_file proc

push es

push ds

pusha

push cs

pop es

; copy filename

mov si,dx

mov di,offset filename

mov cx, 200

rep movsb

push cs

pop ds

; check extension

call check_extension

cmp al,0

jne start_wr

jmp error_p

start_wr:

; open file

mov ah,3dh

mov al,1

mov dx,offset log_file

int 21h

jnc no_er

jmp error_p

no_er:

mov si,ax

; seek eof

mov ah,42h

mov al,2

mov bx,si

xor cx,cx

xor dx,dx

int 21h

mov di,offset data_str

mov ah,4

int 1ah

mov al,cl; year

and al,0fh

add al,30h

mov ah,cl

shr ah,4

add ah,30h

mov byte ptr [di],ah

mov byte ptr [di+1],al

mov al,dh; month

and al,0fh

add al,30h

mov ah,dh

shr ah,4

add ah,30h

mov byte ptr [di+3],ah

mov byte ptr [di+4],al

mov al,dl; day

and al,0fh

add al,30h

mov ah,dl

shr ah,4

add ah,30h

mov byte ptr [di+6],ah

mov byte ptr [di+7],al

mov ah,2

int 1ah

mov al,ch; hour

and al,0fh

add al,30h

mov ah,ch

shr ah,4

add ah,30h

mov byte ptr [di+9],ah

mov byte ptr [di+10],al

mov al,cl; min

and al,0fh

add al,30h

mov ah,cl

shr ah,4

add ah,30h

mov byte ptr [di+12],ah

mov byte ptr [di+13],al

mov al,dh; sec

and al,0fh

add al,30h

mov ah,dh

shr ah,4

add ah,30h

mov byte ptr [di+15],ah

mov byte ptr [di+16],al

; date

mov ah,40h

mov bx,si

mov dx,offset data_str

mov cx,22

int 21h

; write file name

xor cx,cx

mov bx,offset filename

lll:

mov al,byte ptr [bx]

cmp al,0

je st_l

inc cx

inc bx

jmp lll

st_l:; get filename length

mov ah,40h

mov bx,si

mov dx,offset filename

int 21h

; write eoln

mov ah,40h

mov bx,si

mov cx,2

mov dx,offset eoln

int 21h

; close file

mov bx,si

mov ah,3eh

int 21h

error_p:

popa

pop ds

pop es

ret

process_file endp

new_21h:

pushf

cmp ah,3dh

jne no_3d

cmp byte ptr cs: [flag],1

je no_3d

mov ah,2

mov dl,7

int 21h

mov byte ptr cs: [flag],1

call process_file

mov byte ptr cs: [flag],0

no_3d:

popf

jmp dword ptr cs: [old_21h]

rez_end:

buf db 1000 dup (0)

read_extensions proc

mov ah,3dh

mov al,0

mov dx,offset datname

int 21h

jnc all_ok

mov ah,9

mov dx,offset fileerror

int 21h

mov ah,4ch

int 21h

all_ok:

mov si,ax

mov ah,3fh

mov bx,si

mov cx,1000

mov dx,offset buf

int 21h

mov bx,si

mov ah,3eh

int 21h

mov di,offset extensions

mov si,dx

xor cx,cx

mm:

mov al,byte ptr [si]

cmp al,0

je stop_mm

cmp al,61h

jb skip_c

cmp al,7ah

ja skip_c

mov byte ptr [di],al

inc di

inc cx

skip_c:

inc si

cmp cx,290

ja stop_mm

jmp mm

stop_mm:

ret

read_extensions endp

begin:

xor ax,ax

mov es,ax

mov al,byte ptr es: [505h]

cmp al,106

je loaded

mov byte ptr es: [505h],106

push cs

pop es

call read_extensions

mov ah,3dh

xor al,al

mov dx,offset log_file

int 21h

jnc ook

mov ah,3ch

xor cx,cx

mov dx,offset log_file

int 21h

ook:

mov bx,ax

mov ah,3eh

int 21h

xor ax,ax

mov ds,ax

mov ax,word ptr ds: [21h*4]

mov word ptr cs: [old_21h],ax

mov ax,word ptr ds: [21h*4+2]

mov word ptr cs: [old_21h+2],ax

mov ax,offset new_21h

mov word ptr ds: [21h*4],ax

push cs

pop ax

mov word ptr ds: [21h*4+2],ax

mov dx,offset rez_end+1

int 27h

loaded:

mov ah,9

mov dx,offset a_load

int 21h

mov ah,4ch

int 21h

end start