基于UDP的单线程网络点对点数据包收发测试程序

分享一段基于UDP的单线程网络点对点数据包收发测试程序。这段程序我是用来测试使用recvmmsg()与sendmmsg()后的丢包率(这两个函数的信息可以man出来)，使用g++编译，程序中可能有不足的地方还望指出。

  文件一：wrap.h

#ifndef _WRAP_H_
#define _WRAP_H

#ifndef __USE_GNU
#define __USE_GNU
#endif

#include <sys/socket.h>
#include <sys/types.h>
#include <string.h>
#include <stdio.h>
#include <errno.h>
#include <unistd.h>
#include <stdlib.h>
#include <netinet/in.h>
#include <arpa/inet.h>

#define DATNUM  100

#endif

文件二：server.c

/* server.c */
#include "wrap.h"
#define SERV_PORT 8000

int main(void)
{
 struct sockaddr_in servaddr, clitaddr[DATNUM];
 int sockfd, i, n;
 char buf[DATNUM][3];
 struct mmsghdr msgvec[DATNUM];
 struct iovec dataiov[DATNUM];
 struct timespec *timeout;
 timeout = (struct timespec *)malloc(sizeof(struct timespec));
 unsigned long b = 0, a = 0;

 sockfd = socket(AF_INET, SOCK_DGRAM, 0);

 bzero(&servaddr, sizeof(servaddr));
 bzero(clitaddr, sizeof(clitaddr));
 bzero(msgvec, sizeof(msgvec));
 bzero(dataiov, sizeof(dataiov));

 servaddr.sin_family = AF_INET;
 servaddr.sin_addr.s_addr = htonl(INADDR_ANY);
 servaddr.sin_port = htons(SERV_PORT);
 bind(sockfd, (struct sockaddr *)&servaddr, sizeof(servaddr));
 timeout->tv_sec = 5;
 timeout->tv_nsec = 0;
 printf("Accepting connections ...\n");

 while(1) {
     for (i = 0; i < DATNUM; i++) {                 // 准备好待接收的包
            dataiov[i].iov_base = buf[i];
            dataiov[i].iov_len = 3;
            msgvec[i].msg_hdr.msg_name = &clitaddr;
            msgvec[i].msg_hdr.msg_namelen = 16;
            msgvec[i].msg_hdr.msg_iov = &dataiov[i];
            msgvec[i].msg_hdr.msg_iovlen = DATNUM;
     }
     n = recvmmsg(sockfd, msgvec, DATNUM, 0, timeout);
     if (n == -1) {
         b++;
         printf("recv_err_num:%ld\n", b);          // 出错包数量
     }
    else {
         a++;
         printf("recv_crt_num:%ld\n", a);          // 正确接收
     }
 }
}

文件三：client.c

/* client.c */
#include "wrap.h"
#define SERV_PORT 8000

int main(int argc, char *argv[])      // 参数是要发送的数据包个数
{

 struct sockaddr_in servaddr;
 int sockfd, n, i, j, a;
 char m[6] = "CHINA";
 struct mmsghdr msgvec[DATNUM];
 struct iovec  dataiov[DATNUM];

 if (argc != 2) {
    printf("Please input a argument.\n");
    exit(0);
 }
 sockfd = socket(AF_INET, SOCK_DGRAM, 0);
 if (sockfd < 0) {
        printf("socket creating fail!\n");
        return 0;
 }
 bzero(&servaddr, sizeof(struct sockaddr_in));
 bzero(msgvec, sizeof(msgvec));
 bzero(dataiov, sizeof(dataiov));
 servaddr.sin_family = AF_INET;
 inet_pton(AF_INET, "127.0.0.1", &servaddr.sin_addr);
 servaddr.sin_port = htons(SERV_PORT);

 for (i = 0, a = 0; i < atoi(argv[1]); i++) {
        for(j = 0; j < DATNUM; j++) {                // 构建数据包
             bzero(&msgvec[j], sizeof(struct mmsghdr));
             bzero(&dataiov[j], sizeof(struct iovec));
             msgvec[j].msg_hdr.msg_name = &servaddr;
             msgvec[j].msg_hdr.msg_namelen = 16;
             dataiov[j].iov_base = &m;
             dataiov[j].iov_len = 3;
             msgvec[j].msg_hdr.msg_iov = &dataiov[j];
             msgvec[j].msg_hdr.msg_iovlen = DATNUM;
        }

        n = sendmmsg(sockfd, msgvec, DATNUM, 0);
         if (n == -1) {
             printf("sendmmsg error\n");
            exit(0);
        }
        else  a++;

        // usleep(1);     // 测试时最好注释掉，会影响结果
 }
 printf("send_num = %d\n", a);
 return 0;
}