epoll—linux c language —UDP Broadcast

http://neokentblog.blogspot.com/2012/11/udp-broadcast-socket-programming-example.html

server.c

点击(此处)折叠或打开

  1. // gcc server.c -o server
  2. // indent -npro -kr -i8 -ts8 -sob -l280 -ss -ncs -cp1 *

  4. #include <stdio.h>        // for printf() and fprintf()
  5. #include <sys/socket.h>        // for socket(), bind(), and connect()
  6. #include <arpa/inet.h>        // for sockaddr_in and inet_ntoa()
  7. #include <stdlib.h>        // for atoi() and exit()
  8. #include <string.h>        // for memset()
  9. #include <unistd.h>        // for close()
  10. #include <fcntl.h>        // for fcntl()
  11. #include <errno.h>

  13. #include <sys/epoll.h>

  15. #define BUFSIZE 1024        // Size of receive buffer

  17. static int make_socket_non_blocking(int sfd)
  18. {
  19.     int flags, s;

  21.     flags = fcntl(sfd, F_GETFL, 0);

  23.     if (flags == -1) {
  24.         perror("fcntl");
  25.         return -1;
  26.     }

  28.     flags |= O_NONBLOCK;
  29.     s = fcntl(sfd, F_SETFL, flags);

  31.     if (s == -1) {
  32.         perror("fcntl");
  33.         return -1;
  34.     }

  36.     return 0;
  37. }

  39. int main(int argc, char *argv[])
  40. {
  41.     int sockfd;        // Socket descriptors for server
  42.     int broadcast = 1;    // Socket Option.
  43.     struct sockaddr_in srvaddr;    // Broadcast Server Address
  44.     struct sockaddr_in dstaddr;    // Broadcast Destination Address
  45.     struct sockaddr_in cliaddr;    // Broadcast Response Client Address
  46.     int cliaddr_len = sizeof(cliaddr);

  48.     char buffer[BUFSIZE];    // Input and Receive buffer
  49.     int i;            // For loop use
  50.     int running = 1;    // Main Loop

  52.     int epfd;        // EPOLL File Descriptor.
  53.     struct epoll_event ev;    // Used for EPOLL.
  54.     struct epoll_event events[5];    // Used for EPOLL.
  55.     int noEvents;        // EPOLL event number.

  57.     printf("This process is a UDP broadcast process!.\n");

  59.     // Test for correct number of arguments

  61.     if (argc < 4) {
  62.         fprintf(stderr, "Usage: %s <Local Port> <IP> <Remote Port> ...\n", argv[0]);
  63.         exit(1);
  64.     }
  65.     // Create Socket

  67.     if ((sockfd = socket(AF_INET, SOCK_DGRAM, 0)) == -1) {
  68.         perror("Create Sockfd Fail!!\n");
  69.         exit(1);
  70.     }
  71.     // Setup Broadcast Option

  73.     if ((setsockopt(sockfd, SOL_SOCKET, SO_BROADCAST, &broadcast, sizeof(broadcast))) == -1) {
  74.         perror("Setsockopt - SO_SOCKET Fail!!\n");
  75.         exit(1);
  76.     }
  77.     // Nonblocking

  79.     make_socket_non_blocking(sockfd);

  81.     // Reset the addresses

  83.     memset(&srvaddr, 0, sizeof(srvaddr));
  84.     memset(&dstaddr, 0, sizeof(dstaddr));

  86.     // Setup the addresses

  88.     srvaddr.sin_family = AF_INET;
  89.     srvaddr.sin_port = htons(atoi(argv[1]));
  90.     srvaddr.sin_addr.s_addr = INADDR_ANY;

  92.     if (bind(sockfd, (struct sockaddr *)&srvaddr, sizeof(srvaddr)) == -1) {
  93.         perror("bind");
  94.         exit(1);
  95.     }

  97.     dstaddr.sin_family = AF_INET;
  98.     dstaddr.sin_port = htons(atoi(argv[3]));
  99.     inet_pton(AF_INET, argv[2], &(dstaddr.sin_addr.s_addr));

  101.     // Create epoll file descriptor.

  103.     epfd = epoll_create(5);

  105.     // Add socket into the EPOLL set.

  107.     ev.data.fd = sockfd;
  108.     ev.events = EPOLLIN | EPOLLET;
  109.     epoll_ctl(epfd, EPOLL_CTL_ADD, sockfd, &ev);

  111.     // Add STDIN into the EPOLL set.

  113.     ev.data.fd = STDIN_FILENO;
  114.     ev.events = EPOLLIN | EPOLLET;
  115.     epoll_ctl(epfd, EPOLL_CTL_ADD, STDIN_FILENO, &ev);

  117.     while (running) {
  118.         // Wait for events.
  119.         // int epoll_wait(int epfd, struct epoll_event *events, int maxevents, int timeout);
  120.         // Specifying a timeout of -1 makes epoll_wait() wait indefinitely.

  122.         noEvents = epoll_wait(epfd, events, FD_SETSIZE, -1);

  124.         for (i = 0; i < noEvents; i++) {
  125.             if (events[i].events & EPOLLIN && STDIN_FILENO == events[i].data.fd) {
  126.                 memset(buffer, 0, BUFSIZE);
  127.                 fgets(buffer, 1024, stdin);

  129.                 if (strncmp(buffer, "bye", 3) == 0) {
  130.                     printf("Bye.\n");
  131.                     running = 0;
  132.                 }

  134.                 if (sendto(sockfd, buffer, strlen(buffer), 0, (struct sockaddr *)&dstaddr, sizeof(dstaddr)) != -1) {
  135.                     printf("Sent a brocast message: %s", buffer);
  136.                 } else {
  137.                     printf("Sent a brocast message FAIL!!\n");
  138.                     running = 0;
  139.                 }
  140.             } else if (events[i].events & EPOLLIN && sockfd == events[i].data.fd) {
  141.                 memset(buffer, 0, BUFSIZE);

  143.                 while (recvfrom(sockfd, buffer, BUFSIZE, 0, (struct sockaddr *)&cliaddr, (socklen_t *) & cliaddr_len) != -1) {
  144.                     printf("Response from %s_%d: %s", inet_ntoa(cliaddr.sin_addr), ntohs(cliaddr.sin_port), buffer);
  145.                 }

  147.                 if (errno != EAGAIN) {
  148.                     printf("Receive the brocast message response FAIL!!\n");
  149.                     running = 0;
  150.                 }
  151.             }
  152.         }
  153.     }

  155.     // Close the socket

  157.     close(sockfd);
  158.     close(epfd);

  160.     return 0;
  161. }
client.c

点击(此处)折叠或打开

  1. // gcc client.c -o client
  2. // indent -npro -kr -i8 -ts8 -sob -l280 -ss -ncs -cp1 *

  4. #include <stdio.h>        // for printf() and fprintf()
  5. #include <sys/socket.h>        // for socket(), bind(), and connect()
  6. #include <arpa/inet.h>        // for sockaddr_in and inet_ntoa()
  7. #include <stdlib.h>        // for atoi() and exit()
  8. #include <string.h>        // for memset()
  9. #include <unistd.h>        // for close()
  10. #include <fcntl.h>        // for fcntl()
  11. #include <errno.h>

  13. #include <sys/epoll.h>

  15. #define BUFSIZE 1024        // Size of receive buffer

  17. static int make_socket_non_blocking(int sfd)
  18. {
  19.     int flags, s;

  21.     flags = fcntl(sfd, F_GETFL, 0);

  23.     if (flags == -1) {
  24.         perror("fcntl");
  25.         return -1;
  26.     }

  28.     flags |= O_NONBLOCK;
  29.     s = fcntl(sfd, F_SETFL, flags);

  31.     if (s == -1) {
  32.         perror("fcntl");
  33.         return -1;
  34.     }

  36.     return 0;
  37. }

  39. int main(int argc, char *argv[])
  40. {
  41.     int sockfd;        // Socket descriptors for server
  42.     int broadcast = 1;    // Socket Option.
  43.     struct sockaddr_in cliaddr;    // Broadcast Receiver Address
  44.     struct sockaddr_in srvaddr;    // Broadcast Server Address
  45.     int srvaddr_len = sizeof(srvaddr);

  47.     char buffer[BUFSIZE];    // Input and Receive buffer
  48.     int i;            // For loop use
  49.     int running = 1;    // Main Loop
  50.     int rcvlen = 0;        // Receive Message Size

  52.     int epfd;        // EPOLL File Descriptor.
  53.     struct epoll_event ev;    // Used for EPOLL.
  54.     struct epoll_event events[5];    // Used for EPOLL.
  55.     int noEvents;        // EPOLL event number.

  57.     printf("This process is a UDP broadcast echo client process!.\n");

  59.     // Test for correct number of arguments

  61.     if (argc < 2) {
  62.         fprintf(stderr, "Usage: %s <Local Port> ...\n", argv[0]);
  63.         exit(1);
  64.     }
  65.     // Create Socket

  67.     if ((sockfd = socket(AF_INET, SOCK_DGRAM, 0)) == -1) {
  68.         perror("Create Sockfd Fail!!\n");
  69.         exit(1);
  70.     }
  71.     // Nonblocking

  73.     make_socket_non_blocking(sockfd);

  75.     // Reset the addresses

  77.     memset(&cliaddr, 0, sizeof(cliaddr));

  79.     // Setup the addresses

  81.     cliaddr.sin_family = AF_INET;
  82.     cliaddr.sin_port = htons(atoi(argv[1]));
  83.     cliaddr.sin_addr.s_addr = INADDR_ANY;

  85.     if (bind(sockfd, (struct sockaddr *)&cliaddr, sizeof(cliaddr)) == -1) {
  86.         perror("bind");
  87.         exit(1);
  88.     }
  89.     // Create epoll file descriptor.

  91.     epfd = epoll_create(5);

  93.     // Add socket into the EPOLL set.

  95.     ev.data.fd = sockfd;
  96.     ev.events = EPOLLIN | EPOLLET;
  97.     epoll_ctl(epfd, EPOLL_CTL_ADD, sockfd, &ev);

  99.     while (running) {
  100.         // Wait for events.
  101.         // int epoll_wait(int epfd, struct epoll_event *events, int maxevents, int timeout);
  102.         // Specifying a timeout of -1 makes epoll_wait() wait indefinitely.

  104.         noEvents = epoll_wait(epfd, events, FD_SETSIZE, -1);

  106.         for (i = 0; i < noEvents; i++) {
  107.             if (events[i].events & EPOLLIN && sockfd == events[i].data.fd) {
  108.                 memset(buffer, 0, BUFSIZE);

  110.                 while ((rcvlen = recvfrom(sockfd, buffer, BUFSIZE, 0, (struct sockaddr *)&srvaddr, (socklen_t *) & srvaddr_len))
  111.                  != -1) {
  112.                     printf("Receive from %s_%d: %s", inet_ntoa(srvaddr.sin_addr), ntohs(srvaddr.sin_port), buffer);

  114.                     if (sendto(sockfd, buffer, rcvlen, 0, (struct sockaddr *)&srvaddr, sizeof(srvaddr)) == -1) {
  115.                         printf("Send Fail!\n");
  116.                         running = 0;
  117.                         continue;
  118.                     }
  119.                 }

  121.                 if (errno != EAGAIN) {
  122.                     perror("Receive the brocast message response FAIL!!\n");
  123.                     running = 0;
  124.                 }
  125.             }
  126.         }
  127.     }

  129.     // Close the socket

  131.     close(sockfd);
  132.     close(epfd);

  134.     return 0;
  135. }



<script>window._bd_share_config={"common":{"bdSnsKey":{},"bdText":"","bdMini":"2","bdMiniList":false,"bdPic":"","bdStyle":"0","bdSize":"16"},"share":{}};with(document)0[(getElementsByTagName('head')[0]||body).appendChild(createElement('script')).src='http://bdimg.share.baidu.com/static/api/js/share.js?v=89860593.js?cdnversion='+~(-new Date()/36e5)];</script>
阅读(33) | 评论(0) | 转发(0) |
0

上一篇：gnome-terminal — is a terminal emulation application.

下一篇：epoll—linux c language —TCP unicast

相关热门文章
给主人留下些什么吧！~~
评论热议
posted @ 2016-02-01 00:00  张同光  阅读(111)  评论(0)  编辑  收藏  举报