我决定创建一个使用Linux系统调用的简单猜测数字游戏,以及一些C函数来提供更简单的界面.当我将int转换为字符串并在屏幕上打印正确答案时,我似乎遇到了分段错误.

这是输出：

Enter A Number One Through Ten:" : 
3
Response did not match! The Answer Is:Segmentation fault

这是C代码：

// print.c
#include "/usr/include/stdio.h" 
#include "/usr/include/string.h"
#include "/usr/include/stdlib.h"
#include "/usr/include/time.h"
void print(const char* msg)
{
    printf(msg);
    return;
}
int compare(const char* str,const char* str2)
{
    int i = strcmp(str,str2);
    if (i == 0)
    {
        return 1;
    }
    else
    {
       return 0;
    }
}
int divide(int num,int dem)
{
    if (dem == 0)
    {
        printf("Undefined");
        return 0;
    }
    else {
        return (num / dem);
    }
}
int randnum(int maxn)
{

    if (maxn == 0)
    {
        maxn = 1;
    }
    srand(time(0));
    return rand() % maxn;
}
int stoi(const char* str)
{
    return atoi("str");
}
void itos(int n)
{

     char* buf = "5";
     int ret = sprintf(buf,"%i\n",n);
     if (ret == -1){
    printf("Error!");
    return;
     }
     else{
    printf(buf);
     }
     return;

}

这是NASM代码：

      ; Declared C functions.
        extern print 
        extern compare
        extern divide
        extern randnum
        extern stoi
        extern itos
        section .data 
            msg: db 'Enter A Number One Through Ten:" : ',10
            ml: equ $- msg
            t: db 'Response did match!',10
            tl: equ $- t
            f: db 'Response did not match! The Answer Is:',0
            fl: equ $- f
            str2: db 'Hello'
        section .bss
            ;srnum: resb 255
            snum: resb 255
            rnum: resb 255
            num: resb 255
        section .text
            global _start ; Entry point function or label.
        _start:
            ; System call sys_write
            mov eax,4
            mov ebx,1
            mov ecx,msg
            mov edx,ml
            int 80h

        ; System call sys_read
        mov eax,3
        mov ebx,0
        mov ecx,snum
        mov edx,255
        int 80h

        ; Call stoi which converts string to int (parameter 1: is string to convert).
        push snum
        call stoi
        mov [num],eax

        mov ecx,esp
        sub ecx,4
        mov esp,ecx


        ; Call random
        push 10
        call randnum
        mov [rnum],eax


        mov ecx,ecx

        ; Compare the two integers.
        mov eax,num
        cmp eax,[rnum]
        je true
        jne false

    true:
        ; Call sys_write 
        mov eax,4
        mov ebx,1
        mov ecx,t
        mov edx,tl
        int 80h

    false: ; Segmentation fault is somewhere in this label 

        mov eax,f
        mov edx,fl
        int 80h


        push rnum
        call itos 


        ; Calling sys_exit with exit code (0 = ERROR_SUCCESS)
        mov eax,1
        mov ebx,0
        int 80h