x86 assembly - masm32:等待响应的问题

时间:2012-05-21 02:36:13

标签: assembly input x86 masm masm32

我创建了这个程序,它接受两个输入并将它们打印出来(简单,是的,但是它可以用于练习)。它编译,并运行良好,但它没有做我想要的。这是我的代码:

.386 
.model flat, stdcall 
option casemap :none 
include \masm32\include\windows.inc 
include \masm32\include\kernel32.inc 
include \masm32\include\masm32.inc 
includelib \masm32\lib\kernel32.lib 
includelib \masm32\lib\masm32.lib
.data 
   num1 db "Enter a number:", 0 
   num2 db "Enter another number:", 0
.data? 
       buffer1 dd 100 dup(?)
   buffer2 dd 100 dup(?)
.code 
start:
   lea eax, num1
   push eax
   call StdOut
   lea ebx, buffer1
   push ebx
   call StdIn
   hlt
   lea eax, num2
   push eax
   call StdOut
   lea edx, buffer2
   push edx
   call StdIn
   xor eax, eax
   xor ebx, ebx
   xor edx, edx
   lea eax, buffer1
   push eax
   call StdOut
   lea ebx, buffer2
   push ebx
   call StdOut
   push 0 
   call ExitProcess
end start 

显示此输出:

Enter a number: Enter another number:

应该这样做:

Enter a number:
; wait for input.
Enter another number:
; wait for input.
; continue with program.

为什么要在一行打印?我尝试将halt放在那里以停止该过程,但Windows停止程序运行,并说the program is not responding

编辑:

以下是我要编辑的代码:

xor eax, eax
xor ebx, ebx
xor edx, edx
lea eax, buffer1
push eax
call StdOut
lea ebx, buffer2
push ebx
call StdOut

当我使用之前的代码运行时,它会显示"This program is not responding."为什么会这样?

任何帮助都将不胜感激。

此致

Progrmr

1 个答案:

答案 0 :(得分:3)

显然,他会停止执行。它只应用于等待下一个硬件中断,并且只能由操作系统使用。

StdIn不适合您,因为您没有提供缓冲区的长度。所以StdIn失败了,下一个StdOut被执行了。

不要使用hlt,然后按缓冲区的长度,然后将地址推送到缓冲区。

.386 
.model flat, stdcall 
option casemap :none 

include \masm32\include\windows.inc 
include \masm32\include\kernel32.inc 
include \masm32\include\masm32.inc 
include \masm32\include\msvcrt.inc 
include \MASM32\INCLUDE\user32.inc

includelib \masm32\lib\kernel32.lib 
includelib \masm32\lib\masm32.lib
includelib \masm32\lib\msvcrt.lib
includelib \MASM32\LIB\user32.lib

atoi PROTO C strptr:DWORD

.data 
   num1 db "Enter a number:", 0 
   num2 db "Enter another number:", 0
   formatStr db "%s+%s=%d", 0

.data? 
   buffer1 dw 100 dup(?)
   buffer2 dw 100 dup(?)
   buffer3 dw 100 dup(?)
.code 
start:
   lea eax, num1
   push eax
   call StdOut

   mov eax,100
   push eax
   lea eax, buffer1
   push eax
   call StdIn

   lea eax, num2
   push eax
   call StdOut

   mov eax,100
   push eax
   lea eax, buffer2
   push eax
   call StdIn

   lea eax, buffer1
   push eax
   call atoi
   mov ebx,eax

   lea eax, buffer2
   push eax
   call atoi 
   add eax,ebx

   push eax
   lea eax,buffer2
   push eax
   lea eax,buffer1
   push eax
   lea eax,formatStr
   push eax
   lea eax,buffer3
   push eax
   call wsprintf


   lea eax,buffer3
   push eax
   call StdOut

   push 0 
   call ExitProcess

end start

输出: Output

stdcall指示您从右向左推送参数。 此外,您可能会从查看StdIn和StdOut的代码中受益:

StdIn proc lpszBuffer:DWORD,bLen:DWORD

   LOCAL hInput :DWORD
   LOCAL bRead  :DWORD

   invoke GetStdHandle,STD_INPUT_HANDLE
   mov hInput, eax

   invoke SetConsoleMode,hInput,ENABLE_LINE_INPUT or \
                                ENABLE_ECHO_INPUT or \
                                ENABLE_PROCESSED_INPUT

   invoke ReadFile,hInput,lpszBuffer,bLen,ADDR bRead,NULL

   mov eax, bRead

   ret

StdIn endp

StdOut proc lpszText:DWORD

    LOCAL hOutPut  :DWORD
    LOCAL bWritten :DWORD
    LOCAL sl       :DWORD

    invoke GetStdHandle,STD_OUTPUT_HANDLE
    mov hOutPut, eax

    invoke StrLen,lpszText
    mov sl, eax

    invoke WriteFile,hOutPut,lpszText,sl,ADDR bWritten,NULL

    mov eax, bWritten
    ret

StdOut endp