10

如何将int数组中的 MAC 地址转换为 C 中的字符串？例如，我使用以下数组来存储 MAC 地址：

int array[6] = {0x00, 0x0d, 0x3f, 0xcd, 0x02, 0x5f};

如何将其转换为字符串，例如"00:0d:3f:cd:02:5f"？

4

7 回答 7

14

你可以这样做：

char macStr[18];
int array[6] = {0x00, 0x0d, 0x3f, 0xcd, 0x02, 0x5f};

snprintf(macStr, sizeof(macStr), "%02x:%02x:%02x:%02x:%02x:%02x",
         array[0], array[1], array[2], array[3], array[4], array[5]);

如果你想要一个大写的字符串，使用大写的 'X'：

snprintf(macStr, sizeof(macStr), "%02X:%02X:%02X:%02X:%02X:%02X",
         array[0], array[1], array[2], array[3], array[4], array[5]);
于 2013-05-14T18:53:21.777 回答
3 
unsigned char array[6] = {0x00, 0x0d, 0x3f, 0xcd, 0x02, 0x5f};//or BYTE

char str[19];
sprintf(str, "%02x:%02x:%02x:%02x:%02x:%02x",array[0], 
        array[1], array[2], array[3], array[4],array[5]);
于 2013-05-14T18:52:31.373 回答
1

不使用 snprintf，但这只是为了好玩....

#define MAC_LEN 6

static const char _mac[MAC_LEN] = { 0xBC, 0xDD, 0xC2, 0xF0, 0x2E, 0x06 };

int main(void){

char mac[MAC_LEN*2 + 1] = {0}; // added null char

int j = 0;
for( int i = 0;  i < sizeof(_mac) ; i++ )
{
    j = i * 2;
    mac[j] = (((_mac[i] & 0xF0)>>4)&0xF) ;
    mac[j] += (mac[j] <= 9) ? '0' : ('A' - 10);
    j++;
    mac[j] = (_mac[i] & 0x0F);
    mac[j] += (mac[j] <= 9) ? '0' : ('A' -10);
}

printf("Hello World!, my mac address : %s\n", mac);

fflush(stdout);

return 0;
}
于 2019-07-03T15:30:56.253 回答
0

首先，您可能想要调整用于存储 MAC 地址的类型。我认为unsigned char在这种情况下更好。接下来，我建议您创建一个函数来写入 MAC 地址，这样您就不会printf()在代码中的任何地方复制和粘贴相同的语句并调整您要索引的数组。（此外，它允许编译器根据函数参数检查您使用的类型，以确保它是正确的。）

这是类似于 的不可重入解决方案inet_ntoa()和类似于 的可重入解决方案inet_ntoa_r()：

#include <stdio.h>

unsigned char mac[6] = {0x00, 0x0d, 0x3f, 0xcd, 0x02, 0x5f};

char* MACADDR_toString(unsigned char* addr)
{
    static char str[18];

    if(addr == NULL) return "";

    snprintf(str, sizeof(str), "%02x:%02x:%02x:%02x:%02x:%02x", 
             addr[0], addr[1], addr[2], addr[3], addr[4], addr[5]);

    return str;
}

char* MACADDR_toString_r(unsigned char* addr, char* str, size_t size)
{
    if(addr == NULL || str == NULL || size < 18) return NULL;

    snprintf(str, size, "%02x:%02x:%02x:%02x:%02x:%02x", 
             addr[0], addr[1], addr[2], addr[3], addr[4], addr[5]);

    return str;
}

int main(int argc, char* argv[])
{
    char str[18];
    printf("%s\n", MACADDR_toString(mac));
    printf("%s\n", MACADDR_toString_r(mac, str, sizeof(str)));
    return 0;
}
于 2013-05-14T18:58:16.383 回答
0

如果您正在处理无法使用 stdlib 功能的低级内核或驱动程序，则可以将其转换如下 -

#include <stdio.h>

struct ether_addr{
    int ether_addr_octet[6];
};

const char* ntoa(struct ether_addr ea)
{
    static char mstr[13];
    int j=11;
    for (int i=5;i>=0;i--)
    {
        int val = ea.ether_addr_octet[i];
        while (val)
        {
            int k = val%16;
            if (k==10)
                mstr[j--] = 'A';
            if (k==11)
                mstr[j--] = 'B';
            if (k==12)
                mstr[j--] = 'C';
            if (k==13)
                mstr[j--] = 'D';
            if (k==14)
                mstr[j--] = 'E';
            if (k==15)
                mstr[j--] = 'F';
            if (k<10)
                mstr[j--] = k + '0';
            val = val/16;
        }
    }
    mstr[12] = '\0';
    char *parr = mstr;
    printf("%6s\n",mstr);
    return mstr;
}

int main(void) {
    // your code goes here
    struct ether_addr ue;
    ue.ether_addr_octet[0] = 255;
    ue.ether_addr_octet[1] = 255;
    ue.ether_addr_octet[2] = 255;
    ue.ether_addr_octet[3] = 255;
    ue.ether_addr_octet[4] = 255;
    ue.ether_addr_octet[5] = 255;
    char *s = ntoa(ue);
    printf("%s",s);
    return 0;
}
于 2019-07-18T16:41:58.590 回答
0

Gisway 给出了最好的答案，无论如何对我来说......添加额外的东西

...

#include<netinet/in.h>
#include<errno.h>
#include<netdb.h>
#include<stdio.h>   //For standard things
#include<stdlib.h>  //malloc
#include<string.h>  //strlen
#include<netinet/tcp.h> //Provides declarations for tcp header
#include<netinet/ip.h>  //Provides declarations for ip header
#include<netinet/if_ether.h>    //For ETH_P_ALL
#include<net/ethernet.h>    //For ether_header
#include<sys/socket.h>
#include<arpa/inet.h>
#include<sys/ioctl.h>
#include<sys/time.h>
#include<sys/types.h>
#include<unistd.h>

int main()
{

    int saddr_size , data_size;
    struct sockaddr saddr;
        
    unsigned char *buffer = (unsigned char *) malloc(65536); //Its Big!
    
    printf("Starting...\n");
    
    int sock_raw = socket( AF_PACKET , SOCK_RAW , htons(ETH_P_ALL)) ;
    setsockopt(sock_raw , SOL_SOCKET , SO_BINDTODEVICE , ifce , strlen(ifce)+ 1 );
    
    if(sock_raw < 0)
    {
        //Print the error with proper message
        perror("Socket Error");
        return 1;
    }
    while(1)
    {
        saddr_size = sizeof saddr;
        //Receive a packet
        data_size = recvfrom(sock_raw , buffer , 65536 , 0 , &saddr , (socklen_t*)&saddr_size);
        if(data_size <0 )
        {
            printf("Recvfrom error , failed to get packets\n");
            return 1;
        }
        //Now process the packet
        ProcessPacket(buffer , data_size);
    }
    close(sock_raw);
    printf("Finished");
    return 0;
}


void ProcessPacket(buffer , data_size)
{
    struct ethhdr *eth = (struct ethhdr *)Buffer;
    
    char src_mac[19];
    sprintf(src_mac, "%02x:%02x:%02x:%02x:%02x:%02x",eth->h_source[0] , eth->h_source[1] , eth->h_source[2] , eth->h_source[3] , eth->h_source[4] , eth->h_source[5]);
    printf("Mac address: %s\n",src_mac);
}
于 2020-07-26T18:19:32.890 回答
-1

循环调用sprintf() ^_^:

#include <stdio.h>

int array[6] = {0x00, 0x0d, 0x3f, 0xcd, 0x02, 0x5f};

void macaddress_str(int a[], char *buf)
{
    int i;
    for (i = 0; i < 5; i++, buf += 3)
        sprintf(buf, "%02X:", a[i]);
    sprintf(buf, "%02X", a[i]);
}

int main()
{
    char buf[100];
    macaddress_str(array, buf);
    printf("%s\n", buf);
    return 0;
}
于 2013-05-14T18:55:36.157 回答