想要使用 C 语言验证 IPv4 地址，但在点数方面出现错误

Question

这是我的代码

#include<stdio.h>
#include<conio.h>
#include<stdlib.h>
#include<string.h>
#include<ctype.h>
int main()
{
    int alp=0;
    int ch, spaces;
    char str[30];
    int er=0;
    int dot = 3;
    int cl;
    int i, j, k, l;
    int x;
    int y;
    int z;
    int p;
    printf("Enter IPV4 IP address:");//Enter the IP address
    scanf("%s",&str);//For taking input
    char *part;
    char *part1 = strtok(str, ".");
    char *s1 = part1;
    char *part2 = strtok(NULL, ".");
    char *s2 = part2;
    char *part3 = strtok(NULL, ".");
    char *s3 = part3;
    char *part4 = strtok(NULL, ".");
    char *s4 = part4;
    
    if(p < 0 || p > 255)//To check the range of the ip address
    {
       er++; 
        printf("IP Address not in range");
    }
    if (part4[0]=='0')//to check if the 1st position holds zero
    {
        er++;
        printf("\nZero Found. IP address should not containt leading zero");
        
    }
    if(dot != 3)//to check the separaters
    {
        dot--;
        printf("\nValid");
    }
    else
    {
        dot++;
        printf("\nLimit exceeded!! number of dots more than three");
    }
    
    return 0;
}

所以我得到的错误是//如果我输入 192.168.1.1（有效 IP）显示错误限制，则检查我的代码的分隔符部分如果我输入更多点的 IP 显示相同的错误，也会超出限制.

我的那部分代码需要帮助。

Answer 1

首先使用正常和不稳定的 IP 号尝试我的代码并观察其输出。然后将您的代码与我的代码进行比较并检测您的错误。

#include<stdio.h>
#include<conio.h>
#include<stdlib.h>
#include<string.h>
#include<ctype.h>

int dotCount(const char* str) {
    int dots = 0;
    while(*str != NULL) {
        if(*str++ == '.') dots++;
    }
    return dots;
}

int main()
{
    char str[30];
    int er=0;
    int dot = 0;
    printf("Enter IPV4 IP address:");//Enter the IP address
    scanf("%s",str);//For taking input
    puts(str);

    // Dot count check
    dot = dotCount(str);
    if(dot == 3)
    {
        printf("\nDot count ok");
    }
    else
    {
        er++;
        printf("\nLimit exceeded!! number of dots more than three: %d\n", dot);
    }

    char *part;
    part = strtok(str, ".");
    while(part != NULL) {
        dot++;
//      printf("part: %s\n", part); // Part debug
        if(strlen(part) > 1 && *part == '0') {
            er++;
            printf("\nZero Found. IP address should not containt leading zero: %s\n", part);
        }
        int range = atoi(part);
        if(range < 0 || range > 255)//To check the range of the ip address
        {
            er++;
            puts("IP Address not in range\n");
        }
        part = strtok(NULL, ".");
    }

    if(er > 0) {
        printf("%d errors found\n",er);
    }
    else {
        puts("No errors foundi IP adress is ok\n");
    }

    return 0;
}

想要使用 C 语言验证 IPv4 地址，但在点数方面出现错误

Want validate IPv4 address using C language but getting error in number of dots

c

validation

ipv4