linux上c语言 获得网络接口的统计值

这个东东，蛮好玩的。其实就是读取了/proc/net/dev 文件。

 

 

struct netdev_stats {
    unsigned long long rx_packets_m;    /* total packets received       */
    unsigned long long tx_packets_m;        /* total packets transmitted    */
    unsigned long long rx_bytes_m;  /* total bytes received         */
    unsigned long long tx_bytes_m;  /* total bytes transmitted      */
    unsigned long rx_errors_m;      /* bad packets received         */
    unsigned long tx_errors_m;      /* packet transmit problems     */
    unsigned long rx_dropped_m;     /* no space in linux buffers    */
    unsigned long tx_dropped_m;     /* no space available in linux  */
    unsigned long rx_multicast_m;   /* multicast packets received   */
    unsigned long rx_compressed_m;
    unsigned long tx_compressed_m;
    unsigned long collisions_m;

    /* detailed rx_errors: */
    unsigned long rx_length_errors_m;
    unsigned long rx_over_errors_m; /* receiver ring buff overflow  */
    unsigned long rx_crc_errors_m;  /* recved pkt with crc error    */
    unsigned long rx_frame_errors_m;        /* recv'd frame alignment error */
    unsigned long rx_fifo_errors_m; /* recv'r fifo overrun          */
    unsigned long rx_missed_errors_m;       /* receiver missed packet     */
    /* detailed tx_errors */
    unsigned long tx_aborted_errors_m;
    unsigned long tx_carrier_errors_m;
    unsigned long tx_fifo_errors_m;
    unsigned long tx_heartbeat_errors_m;
    unsigned long tx_window_errors_m;
};

 

static char * get_name(char * name, char * p)
{
    char * t = NULL;

    /*interface only contains lowercase letters*/
    while((*p<'a') || (*p>'z')) p++;

    if ((t =  strchr(p, ':')))
    {
        memcpy(name, p, t-p);
        return t+1;
    }
    else return NULL;
}

#define PROC_NET_DEV_FNAME "/proc/net/dev"
int get_devstats(char * ifname, struct netdev_stats * pstats)
{
    FILE * fp;
    char name[256] = {0};
    char buf[256] = {0};
    char * s = NULL;
    int found = 0;


    if (!ifname || !pstats) return -1;

    fp = fopen(PROC_NET_DEV_FNAME, "r");

    if (!fp) return -1;
    else
    {
        /*by pass the first 2 lines, they are titles*/
        fgets(buf, sizeof(buf), fp );
        fgets(buf, sizeof(buf), fp );

        memset(buf, 0 ,sizeof(buf));
        while (fgets(buf, sizeof(buf), fp ))
        {
            memset(name, 0, sizeof(name));
            s = get_name(name, buf);

            if (s)
            {
                sscanf(s, "%llu%llu%lu%lu%lu%lu%lu%lu%llu%llu%lu%lu%lu%lu%lu%lu",
                       &pstats->rx_bytes_m, /* missing for 0 */
                       &pstats->rx_packets_m,
                       &pstats->rx_errors_m,
                       &pstats->rx_dropped_m,
                       &pstats->rx_fifo_errors_m,
                       &pstats->rx_frame_errors_m,
                       &pstats->rx_compressed_m, /* missing for <= 1 */
                       &pstats->rx_multicast_m, /* missing for <= 1 */
                       &pstats->tx_bytes_m, /* missing for 0 */
                       &pstats->tx_packets_m,
                       &pstats->tx_errors_m,
                       &pstats->tx_dropped_m,
                       &pstats->tx_fifo_errors_m,
                       &pstats->collisions_m,
                       &pstats->tx_carrier_errors_m,
                       &pstats->tx_compressed_m /* missing for <= 1 */
                    );

                if(!strncmp(name, ifname, strlen(ifname))) 
                {
                    found = 1;
                    break;
                       
                    debug("name :%s/n", name);
                    debug("%llu:%llu:%lu:%lu:%lu:%lu:%lu:%lu:%llu:%llu:%lu:%lu:%lu:%lu:%lu:%lu:/n",
                           pstats->rx_bytes_m, /* missing for 0 */
                           pstats->rx_packets_m,
                           pstats->rx_errors_m,
                           pstats->rx_dropped_m,
                           pstats->rx_fifo_errors_m,
                           pstats->rx_frame_errors_m,
                           pstats->rx_compressed_m, /* missing for <= 1 */
                           pstats->rx_multicast_m, /* missing for <= 1 */
                           pstats->tx_bytes_m, /* missing for 0 */
                           pstats->tx_packets_m,
                           pstats->tx_errors_m,
                           pstats->tx_dropped_m,
                           pstats->tx_fifo_errors_m,
                           pstats->collisions_m,
                           pstats->tx_carrier_errors_m,
                           pstats->tx_compressed_m /* missing for <= 1 */
                        );               
                }

            }
            else continue;
        }
       
        fclose(fp);
    }

    if (!found) return -1;
    else  return 0;
}

 

int main()

{

     struct netdev_stats wl_pstats;

     get_devstats("wl0", &wl_pstats);

 

     return 0;

}