同时处理TCP和UDP请求的回射服务器

server.cpp

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

#define MAX_EVENT_NUMBER 1024
#define TCP_BUFFER_SIZE 512
#define UDP_BUFFER_SIZE 1024

int setnonblocking(int fd)
{
    int old_option = fcntl(fd, F_GETFL);
    int new_option = old_option | O_NONBLOCK;
    fcntl(fd, F_SETFL, new_option);
    return old_option;
}

void addfd(int epollfd, int fd)
{
    epoll_event event;
    event.data.fd = fd;
    event.events = EPOLLIN | EPOLLET;
    epoll_ctl(epollfd, EPOLL_CTL_ADD, fd, &event);
    setnonblocking(fd);    
}
int main(int argc, char* argv[])
{
    if(argc != 2)
    {
        printf("usage: %s port\n", basename(argv[0]));
        return 1;
    }
    int port = atoi(argv[1]);
    int ret = 0;
    int listenfd = socket(AF_INET, SOCK_STREAM, 0);
    assert(listenfd >= 0);

    struct sockaddr_in address;
    bzero(&address, sizeof(address));
    address.sin_family = AF_INET; //ipv4
    address.sin_addr.s_addr = htonl(INADDR_ANY);
    address.sin_port = htons(port);

    ret = bind(listenfd, (struct sockaddr*)&address, sizeof(address));
    assert(ret != 1);

    ret = listen(listenfd, 5);
    assert(ret != -1);

    /*创建UDP socket, 并将其捆绑到端口port上*/
    bzero(&address, sizeof(address));
    address.sin_family = AF_INET;
    address.sin_addr.s_addr = htonl(INADDR_ANY);
    address.sin_port = htons(port);
    int udpfd = socket(PF_INET, SOCK_DGRAM, 0);
    assert(udpfd >= 0);

    ret = bind(udpfd, (struct sockaddr*)&address, sizeof(address));
    assert(ret != 1);

    epoll_event events[MAX_EVENT_NUMBER];
    int epollfd = epoll_create(5);
    assert(epollfd != -1);
    /*注册TCP socket 和 UDP socket 上的可读事件*/
    addfd(epollfd, listenfd);
    addfd(epollfd, udpfd);

    while(1)
    {
        int number = epoll_wait(epollfd, events, MAX_EVENT_NUMBER, -1);
        //printf("number = %d\n", number);
        if(number < 0)
        {
            printf("epoll failure\n");
            break;
        }
        for(int i = 0; i < number; i++)
        {
            int sockfd = events[i].data.fd;
            if(sockfd == listenfd)
            {
                printf("connect arrived\n");
                struct sockaddr_in client_address;
                socklen_t client_addrlength = sizeof(client_address);
                int connfd = accept(listenfd, (struct sockaddr*)&client_address, &client_addrlength);
                if(connfd <= 0)
                {
                    perror("accept ");
                }
                addfd(epollfd, connfd);
            }
            else if(sockfd == udpfd)
            {
                char buf[UDP_BUFFER_SIZE];
                memset(buf, '\0', UDP_BUFFER_SIZE);
                struct sockaddr_in client_address;
                socklen_t client_addrlength = sizeof(client_address);
                ret = recvfrom(udpfd, buf, UDP_BUFFER_SIZE - 1, 0,
                              (struct sockaddr*)&client_address, &client_addrlength);
                if(ret > 0)
                {
                    sendto(udpfd, buf, UDP_BUFFER_SIZE - 1, 0,
                          (struct sockaddr*)&client_address, client_addrlength);
                }
            }
            else if(events[i].events & EPOLLIN)
            {
                char buf[TCP_BUFFER_SIZE];
                while(1)
                {
                    memset(buf, '\0', TCP_BUFFER_SIZE);
                    ret = recv(sockfd, buf, TCP_BUFFER_SIZE - 1, 0);
                    if(ret < 0)
                    {
                        if((errno == EAGAIN) || (errno == EWOULDBLOCK))
                        {
                            break;  //EAGAIN
                                    //非阻塞模式下调用了阻塞操作，在该操作没有完成就返回这个错误
                                    //这个错误不会破坏socket的同步，不用管它，下次循环接着recv就可以
                        }
                        close(sockfd);
                        break;
                    }
                    else if(ret == 0)
                    {
                        close(sockfd);
                    }
                    else
                    {
                        send(sockfd, buf, ret, 0);
                    }
                }
            }
            else
            {
                printf("something else happend\n");
            }
        }
    }
    close(listenfd);
    return 0;
}

tcp_client.cpp

/*************************************************************************
    > File Name: client.c
    > Author:Sanjingye 
    > Mail: 
    > Created Time: 2018年03月06日 星期二 16时28分05秒
 ************************************************************************/

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

char* s_gets(char* st,int n)
{
    char* ret_val;
    int i=0;
    ret_val=fgets(st,n,stdin);
    if(ret_val)
    {
        while(st[i]!='\n'&&st[i]!='\0')
            i++;
        if(st[i]=='\n')
            st[i]='\0';
        else
            while(getchar()!='\n')
                continue;
    }
    return ret_val;
}

int main()
{
    int serfd;
    struct sockaddr_in server_address;
    memset(&server_address, 0, sizeof(server_address));
    server_address.sin_family = AF_INET;
    server_address.sin_port = htons(8080);
    if(inet_pton(AF_INET, "127.0.0.1",&server_address.sin_addr)==0)
    {
        printf("invalid server ip address\n");
        return 1;
    }
    serfd = socket(AF_INET, SOCK_STREAM, 0);
    if(serfd < 0)
    {
        perror("socket:");
        return 1;
    }
    if((connect(serfd, (struct sockaddr*)&server_address, sizeof(server_address))) < 0)
    {
        perror("connect");
        return 1;
    }
    char buff[1024];
    while(1)
    {
        printf("client:> ");
        s_gets(buff, 1024);
        //puts(buff);
        write(serfd, (void*)buff, strlen(buff));
        if((read(serfd, (void*)buff, sizeof(buff))) <= 0)
        {
            break;
        }
        printf("server:> %s\n",buff);
    }
    close(serfd);
}

udp_client.cpp

/*************************************************************************
    > File Name: udp_client.cpp
    > Author:Sanjingye 
    > Mail: 
    > Created Time: 2018年03月14日 星期三 19时39分21秒
 ************************************************************************/

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

char* s_gets(char* st,int n)
{
    char* ret_val;
    int i=0;
    ret_val=fgets(st,n,stdin);
    if(ret_val)
    {
        while(st[i]!='\n'&&st[i]!='\0')
            i++;
        if(st[i]=='\n')
            st[i]='\0';
        else
            while(getchar()!='\n')
                continue;
    }
    return ret_val;
}

int main()
{
    int serfd;
    struct sockaddr_in server_address;
    socklen_t len = sizeof(server_address);
    memset(&server_address, 0, sizeof(server_address));
    server_address.sin_family = AF_INET;
    server_address.sin_port = htons(8080);
    if((inet_pton(AF_INET, "127.0.0.1", &server_address.sin_addr) == 0))
    {
        printf("invalid server ip address\n");
        return 1;
    }
    serfd = socket(AF_INET, SOCK_DGRAM, 0);
    if(serfd < 0)
    {
        perror("socket");
        return 1;
    }
    char buff[1024];
    while(1)
    {
        printf("udp_client:> ");
        s_gets(buff, 1024);
        sendto(serfd, buff, strlen(buff), 0,(struct sockaddr*)&server_address, len);
        if((recvfrom(serfd, buff, 1024, 0, (struct sockaddr*)&server_address, &len)) < 0)
        {
            break;
        }
        printf("server:> %s\n", buff);
    }
    close(serfd);
}