Lab

.386
.model flat, stdcall
option casemap :none
include includes\windows.inc
include includes\masm32.inc
include includes\kernel32.inc
include includes\user32.inc
include includes\macros\macros.asm
includelib includes\masm32.lib
includelib includes\kernel32.lib
includelib includes\user32.lib

.data
 aszPrompt db 'Expression: ', 0Dh, 0Ah, 0
 aszPressEnter db 0Dh, 0Ah, 0Dh, 0Ah, "Press ENTER to exit", 0
 aszResult db 10, 13, "Result of your equation is %d", 0

 OpAdd equ '+'
 OpSub equ '-'
 OpMul equ '*'
 OpDiv equ '/'

 AllowedChars db '=+-*/0123456789'
 LenAllowedChars equ $-AllowedChars
 OpChars db '=+-*/'
 LenOpChars equ $-OpChars

.data?
 hConsoleOutput HANDLE ?
 hConsoleInput HANDLE ?
 Buffer db 1024 dup(?)
 BufLen dd ?
 Result dd ?
 Op1 dd ?
 Op2 dd ?
 Operation db ?
.code

PrevOperation proc
   mov eax, [Op1]
   cdq
   mov ebx, [Op2]
   cmp [Operation], OpAdd
   jne @@Sub
   add eax, ebx
   jmp @@Calc
  @@Sub:
   cmp [Operation], OpSub
   jne @@Mul
   sub eax, ebx
   jmp @@Calc
  @@Mul:
   cmp [Operation], OpMul
   jne @@Div
   mul ebx
  @@Div:
   cmp [Operation], OpDiv
   jne @@Calc
   idiv ebx
  @@Calc:
   mov [Op1], eax
   mov [Op2], 0
   mov al, [esi-1]
   mov [Operation], al
  ret
PrevOperation endp

main proc

  ;получение описателей ввода и вывода консоли
  invoke GetStdHandle, STD_INPUT_HANDLE
  mov hConsoleInput, eax

  invoke GetStdHandle, STD_OUTPUT_HANDLE
  mov hConsoleOutput, eax

  invoke ClearScreen

  ;ввод выражения
  invoke WriteConsole, hConsoleOutput, ADDR aszPrompt, LENGTHOF aszPrompt-1, ADDR BufLen, NULL
  invoke ReadConsole, hConsoleInput, ADDR Buffer, LENGTHOF Buffer, ADDR BufLen, NULL
  lea esi, [Buffer] ;удаление из буффера
  add esi, [BufLen] ;символов перевода строки
  mov [esi-2],word ptr 0
  sub [BufLen], 2

  ;обработка выражение во введённой строке
  mov eax, 0
  mov [Op1], 0
  mov [Op2], 0
  mov [Operation], OpAdd

  lea esi, [Buffer]
  mov ecx, [BufLen]
  @@GetCmd:
   push ecx
   lodsb
   ;проверка корректности введенных символов
   lea edi, [AllowedChars]
   mov ecx, [LenAllowedChars]
   repne scasb
   jnz @@Next
  @@ProcessChar:
   lea edi, [OpChars]
   mov ecx, [LenOpChars]
   repne scasb
   jz @@DoOperation
  @@TestDigits:
   ;введена цифра
   and eax, 0FFh
   sub al, '0'
   mov ebx, [Op2]
   lea eax, [eax+8*ebx]
   lea eax, [eax+2*ebx]
   mov [Op2], eax

   pop ecx
   push ecx
   cmp ecx, 1
   jne @@Next

  @@DoOperation:
   ;сначала завершается предыдущая операция
   call PrevOperation
   cmp al, '-'
   jne @@Next
   pop ecx
   jmp @@Break
  @@Next:
   pop ecx
  loop @@GetCmd
@@Break:
ResultShow:
  ;Вывод результатов
  mov eax, [Op1]
  invoke wsprintf, ADDR Buffer, ADDR aszResult, eax
  mov [BufLen], eax
  invoke WriteConsole, hConsoleOutput, ADDR Buffer, BufLen, ADDR BufLen, NULL

  ;ожидание нажатия на ENTER
  invoke WriteConsole, hConsoleOutput, ADDR aszPressEnter, LENGTHOF aszPressEnter - 1, ADDR BufLen, NULL
  invoke ReadConsole, hConsoleInput, ADDR Buffer, LENGTHOF Buffer, ADDR BufLen, NULL

  invoke ExitProcess, 0
main endp

end main