实验三socket编程代码.rar_socket编程_tcp/udp_一对多聊天_多人聊天室_计算机网络实验

#include <stdio.h> #include <stdlib.h> #include <string.h> #include <sys/socket.h> #include <netinet/in.h> #include <arpa/inet.h> #include <unistd.h> #include <error.h> #include <sys/types.h> //process ID #include <signal.h> //clear the Zombie process //global variable for client server char recv_msg[255]; //receive the massege from the client char send_msg[255]; //send massege to the server /*Inverse order function, reverse order of the received information*/ void reverse() { int recv_len = strlen(recv_msg),i; //the length of recv_msg; i for loop for(i=0;i<recv_len;i++) { send_msg[i] = recv_msg[recv_len - i - 1]; //Inverse order for the massege } send_msg[i] = 0; //the last one is NULL to be the end of the alphabetic string } /*main function*/ int main(int argc, char *argv[]) { struct sockaddr_in server_addr,peer_addr; //group addr int server_sock_listen, server_sock_data; int addr_len; pid_t pid; //defining the process ID,requires the introduction of the header file #include <sys/types.h> if(argc == 2) // example:./server2 port { //Specify the server address server_addr.sin_family = AF_INET; //INADDR_ANY Represents all native IP addresses server_addr.sin_addr.s_addr = htonl(INADDR_ANY); server_addr.sin_port = htons(atoi(argv[1])); //set port number memset(&server_addr.sin_zero, 0, sizeof(server_addr.sin_zero)); //fill zero to satisfy the length requirement because of the Inther /*first step: create server:socket()*/ server_sock_listen = socket(AF_INET, SOCK_STREAM, 0); if (server_sock_listen == -1) { perror("Create socket failed!"); return 0; } /*second step: binding socket and address:bind() including error handle*/ if(bind(server_sock_listen, (struct sockaddr *)&server_addr, sizeof(server_addr)) == -1) { perror("Bind failed!"); //bind fail to say if(close(server_sock_listen)==-1) //close the server listen socket for failing { perror("Close sock listen failed!"); //show listen sock close fail } return 0; } /*third step: monitor socket:listen() including error handle*/ if(listen(server_sock_listen, 0) == -1) { perror("Listen failed!"); //listen fail to say if(close(server_sock_listen)==-1) //close the server listen socket for failing { perror("Close sock listen failed!"); //show listen sock close fail } return 0; } // continuous loop,error handling,create chlid process to handle each client separately while(1) { printf("----Sever is listening...----\n"); /*fourth step: Accept() can accept more than one client*/ server_sock_data = accept(server_sock_listen, (struct sockaddr *)&peer_addr, &addr_len); if(server_sock_data == -1) { perror("Accept failed"); //accept fail to say if(close(server_sock_listen)==-1) //close the server listen socket for failing { perror("Close sock listen failed!"); //show listen sock close fail } return 0; //return 0 represents a normal exit of the program } else { //show the client the server has accepted printf("Accept %s:%d\n",inet_ntoa(peer_addr.sin_addr),peer_addr.sin_port); /*fifth step: fork() create multiple processes to implement concurrent services*/ signal(SIGCHLD,SIG_IGN); //clear the Zombie process //the parent process returns the process number of the child process pid.The child process returns 0 pid = fork(); if(pid == -1) // fork failed { printf("fork error\n"); //show fail return 1; //return 1 represents an abnormal exit of the program } else if(pid == 0) //fork succeed:child process to do { /**********************************the rest is as the same from the task1***********************************************/ /*sixth step: send()/recv()*/ while(1) { /* recv() and show */ //Accept group initialization is NULL memset(recv_msg, 0, sizeof(recv_msg)); int recv_ret;//record the length of the massege from server recv_ret = recv(server_sock_data, recv_msg, sizeof(recv_msg), 0); //receive succeed if(recv_ret > 0) { //show the massege the server recvive from which client printf(" From %s:%d : %s\n",inet_ntoa(peer_addr.sin_addr), peer_addr.sin_port, recv_msg); //while receiving "bye" or "Esc",close socket if(strcmp(recv_msg, "bye") == 0 ||recv_msg[0] == 27) { printf("Close %s:%d\n",inet_ntoa(peer_addr.sin_addr),peer_addr.sin_port); // Close server socket to exit if(close(server_sock_data) == -1) { perror("Close sock data failed!"); return 0; } break; } } else if(recv_ret == 0) //The other party has closed the connection { // Close server socket to exit if(close(server_sock_data) == -1) { perror("Close sock data failed!"); return 0; } } else { perror("Recv failed!"); return 0; } /*input and send()*/ reverse(); //Call function for inverse order Transformation of Information //show what the server replys to the client who sent the massege just printf(" Reply %s:%d : %s\n",inet_ntoa(peer_addr.sin_addr), peer_addr.sin_port, send_msg); if(send(server_sock_data, send_msg, strlen(send_msg), 0) == -1) { perror("Reply failed!");return 0; } } } else //close the parent process { // Close server socket to exit //if(close(server_sock_data) == -1) //{ // perror("Close sock data failed!"); //} } } }//first while(1) end /*seventh step: close listen socket */ if(close(server_sock_listen) == -1) { perror("Close sock listen failed!");return 0; } }//the argc number is 2, as server :./server2 port else { printf("argc error!\n"); //the argc number is not right,cannot run return 0; } }//main end