linux 网络编程 epoll 实现

linux 网络编程 epoll

service代码

#include <stdio.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/epoll.h>
#include <stdlib.h>
#include <netinet/in.h>
#include <unistd.h>
#include <arpa/inet.h>
#include <ctype.h>
#include <string.h>
#define LISTEN_PORT 8000
int main()
{
    // create socket
    int server_socket = socket(AF_INET,SOCK_STREAM,0);
    if (server_socket != -1)
    {
        //bind 
        struct sockaddr_in server_addr;
        socklen_t len = sizeof(struct sockaddr_in);
        server_addr.sin_family = AF_INET;
        server_addr.sin_port = htons(LISTEN_PORT);
        server_addr.sin_addr.s_addr = INADDR_ANY; //监听本机全部地址
        int nResult = bind(server_socket,(struct sockaddr*)&server_addr,len);
        if (nResult != -1)
        {
            //listen
            nResult = listen(server_socket,256);
            if (nResult != -1)
            {
                //epoll
                int epfd = epoll_create(10);
                if (epfd < 0)
                {
                    perror("epoll_create error \n");
                    close(server_socket);
                    exit(-1);
                }
                struct epoll_event evt;
                evt.events = EPOLLIN;
                evt.data.fd = server_socket;
                nResult = epoll_ctl(epfd,EPOLL_CTL_ADD,server_socket,&evt);
                if (nResult < 0)
                {
                    perror("epoll_ctl error \n");
                    close(server_socket);
                    exit(-1);
                }
                while (1)
                {
                    //accept
                    struct epoll_event event_results[20];
                    int nRet_Count = epoll_wait(epfd,event_results,20,-1);
                    for (size_t i = 0; i < nRet_Count; i++)
                    {
                        if ((event_results[i].events & EPOLLIN))
                        {
                            if (event_results[i].data.fd == server_socket)
                            {
                                // client connect 
                                struct sockaddr_in client_addr;
                                socklen_t nClient_socklen = sizeof(struct sockaddr_in);
                                int client_sock = accept(server_socket,(struct sockaddr *)&client_addr,&nClient_socklen);
                                if (client_sock != -1)
                                {
                                    struct epoll_event client_evn;
                                    client_evn.events = EPOLLIN;
                                    client_evn.data.fd = client_sock;
                                    //add client socket
                                    epoll_ctl(epfd,EPOLL_CTL_ADD,client_sock,&client_evn);
                                }
                            }
                            else
                            {
                                //client send data
                                char buf[BUFSIZ];
                                int nSize = read(event_results[i].data.fd,buf,BUFSIZ);
                                if (nSize <= 0)
                                {
                                    //client close socket 
                                    epoll_ctl(epfd,EPOLL_CTL_DEL,event_results[i].data.fd,&event_results[i]);
                                    close(event_results[i].data.fd);
                                }
                                else if (nSize > 0)
                                {
                                    for (size_t i = 0; i < nSize; i++)
                                    {
                                        buf[i] = toupper(buf[i]);
                                    }
                                    write(event_results[i].data.fd,buf,nSize);
                                }
                            }
                            
                        }
                        
                    }
                    
                }
                
            }
            
        }   
        //close
        close(server_socket);
    }
    
    return 0;
}

client 代码

#include <stdio.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/epoll.h>
#include <stdlib.h>
#include <netinet/in.h>
#include <unistd.h>
#include <arpa/inet.h>
#include <ctype.h>
#include <string.h>
#define LISTEN_PORT 8000
#define REQ_HOST "127.0.0.1"
int main()
{
    int dest_socket = socket(AF_INET,SOCK_STREAM,0);
    if (dest_socket != -1)
    {
        struct sockaddr_in dest_addr;
        socklen_t len = sizeof(struct sockaddr_in);
        dest_addr.sin_addr.s_addr = inet_addr(REQ_HOST);
        dest_addr.sin_port = htons(LISTEN_PORT);
        dest_addr.sin_family = AF_INET;
        int nResult = connect(dest_socket,(struct sockaddr*)&dest_addr,len);
        if (nResult != -1)
        {

            while (1)
            {
                char buf [BUFSIZ];
                bzero(buf,BUFSIZ);
                printf("please input send data:\n");
                scanf("%s",buf);
                if (!strcmp(buf,"quit"))
                {
                    break;
                }
                write(dest_socket,buf,strlen(buf));
                int nSize = read(dest_socket,buf,BUFSIZ);
                if (nSize <= 0)
                {
                    break;
                }
                else
                {
                    buf[nSize] = '\0';
                    printf("%s\n",buf);
                }    
            }
            
        }    
        //close 
        close(dest_socket);
    }
    
    return 0;
}