7lab.asm

.model small
.286

.data

cmd_size db ?
maxCMDSize equ 127
cmd_text db maxCMDSize + 2 dup(0)
folderPath db maxCMDSize + 2 dup(0)

DTAsize equ 2Ch
DTAblock db DTAsize dup(0)

startText db "SUPERPARENT Program is started", '$'
endText db "SUPERPARENT Program is ended", '$'
reallocErrorMessage db "Bad relocation memory. Error code: ", '$'
runEXEErrorText db "Error running other program. Error code: ", '$'
badFolderErrorText db "Open directory error", '$'

                                        ;EXEC Parameter Block
EPBstruct 	dw 0                        ;0 - èñïîëüçóåòñÿ òåêóùåå îêðóæåíèå
			dw offset line,0
			dw 005Ch, 0, 006Ch, 0		;Àäðåñà FCB (File control block) ïðîãðàììû
line db 125
	 db " /?"
line_text db 122 dup(?)

EPBlen dw $ - EPBstruct

extensionEXEFile db "*.exe", 0

DataLength=$-cmd_size

.stack 100h
.code

newline MACRO
	push ax
	push dx
	
	mov dl, 10
	mov ah, 02h
	int 21h

	mov dl, 13
	mov ah, 02h
	int 21h

	pop dx
	pop ax
ENDM

println MACRO info
	push ax
	push dx

	mov ah, 09h
	mov dx, offset info
	int 21h

	newline

	pop dx
	pop ax
ENDM

printErrorCode MACRO        ;Âûâîä ñèìâîëà îøèáêè
	add al, '0'
	mov dl, al
	mov ah, 06h
	int 21h

	newline
ENDM

main:
	                                                                ;Ïåðåâûäåëåíèå ïàìÿòè
	mov ah, 4Ah                                                     ;4Ah - èçìåíèòü ðàçìåð áëîêà ïàìÿòè
	mov bx, ((CodeLength / 16) + 1) + ((DataLength / 16) + 1) + 32	;Òðåáóåìûé ðàçìåð â ïàðàãðàôàõ
	int 21h

	jnc startOfMainProgram                                          ;Ïåðåõîä, åñëè ïåðåíîñ íå óñòàíîâëåí
                                                                    ;åñëè CF=1 => îøèáêà(â AX - êîä îøèáêè)
	println reallocErrorMessage

	printErrorCode

	mov ax, 1

	jmp endMain

startOfMainProgram:
	mov ax, @data
	mov es, ax

	xor ch, ch
	mov cl, ds:[80h]			
	mov cmd_size, cl 		    ;Ñîõðàíÿåì ðàçìåð ñòðîêè
	mov bh, cl
	dec bh
	mov si, 82h                 ;Ïåðåïèñûâàåì â cmd_text ïåðåäàííûé ïóòü
	mov di, offset cmd_text
	rep movsb

	mov ds, ax                  ;DS óêàçûâàåò íà äàííûå

	println startText
    mov cmd_size, bh
   
	call parseCMD
	
	mov ah, 3Bh                             ;Ñìåíèòü êàòàëîã
    mov dx, offset folderPath
    int 21h
    jc openDirectoryError                   ;CF = 1 => îøèáêà

	call findFirstFile
	cmp ax, 0
	jne endMain				    ;Åñëè áûëè îøèáêè âûõîäèì èç ïðîãðàììû

	call runEXE
	cmp ax, 0
	jne endMain				    ;Åñëè áûëè îøèáêè âûõîäèì èç ïðîãðàììû

runFile:
	call findNextFile
	cmp ax, 0
	jne endMain				    ;Åñëè áûëè îøèáêè âûõîäèì èç ïðîãðàììû

	call runEXE
	cmp ax, 0
	jne endMain				    ;Åñëè áûëè îøèáêè âûõîäèì èç ïðîãðàììû

	jmp runFile

openDirectoryError:
	println badFolderErrorText
	
endMain:
	println endText

	mov ah, 4Ch                 ;Çàâåðøåíèå ïðîãðàììû
	int 21h

parseCMD PROC
	push bx
    push cx
    push dx
    
	mov si, offset cmd_text
    mov di, offset folderPath
    mov cl, cmd_size
    xor ch,ch
    rep movsb
    
    pop dx
    pop cx
	pop bx
	ret	
ENDP

runEXE PROC
	push bx
	push dx

	mov ax, 4B00h				    ;Çàãðóçèòü è âûïîëíèòü ïðîãðàììó
	mov bx, offset EPBstruct        ;Àäðåñ áëîêà ïàðàìåòðîâ EPB
	mov dx, offset DTAblock + 1Eh	;Ïîëó÷àåì èìÿ ôàéëà èç DTA
	int 21h
	
	jnc runEXEAllGood

	println runEXEErrorText
	printErrorCode

	mov ax, 1

	jmp runEXEEnd

runEXEAllGood:
	mov ax, 0

runEXEEnd:
	pop dx
	pop bx
	ret
ENDP

installDTA PROC
	mov ah,1Ah                      ;1Ah - óñòàíîâèòü îáëàñòü DTA
    mov dx, offset DTAblock
    int 21h
    ret
ENDP

findFirstFile PROC
	call installDTA

    mov ah,4Eh                      ;Íàéòè ïåðâûé ôàéë 
    xor cx,cx               		;Àòðèáóò ôàéëà äëÿ ñðàâíåíèÿ 
    mov dx, offset extensionEXEFile ;Àäðåñ ñòðîêè ñ èìåíåì ôàéëà äëÿ ïîèñêà (ìàñêà .exe)
    int 21h

	jnc findFirstFileAllGood

	mov ax, 1

	jmp findFirstFileEnd

findFirstFileAllGood:
	mov ax, 0

findFirstFileEnd:

	ret
ENDP

findNextFile PROC
	call installDTA

	mov ah,4Fh                    ;Íàéòè ñëåäóþùèé ôàéë
    mov dx, offset DTAblock       ;DTA äîëæíà ñîäåðæàòü äàííûå îò ïðåäûäóùåãî âûçîâà 4Eh èëè 4Fh
    int 21h

	jnc findNextFileAllGood

	mov ax, 1

	jmp findNextFileEnd

findNextFileAllGood:
	mov ax, 0

findNextFileEnd:

	ret
ENDP

CodeLength = $ - main

end main