multi_basic_server.cpp

#include <iostream>
#include <winsock2.h>
#include <thread>
using namespace std;

#define PACKET_SIZE 1024

WSADATA wsa;
SOCKET skt,*client_sock;
SOCKADDR_IN *client;
int *client_size,MAX;

void recv_data(SOCKET &s,int client_num){
	char buf[PACKET_SIZE];
	
	while(1){
		ZeroMemory(buf,PACKET_SIZE);
		if(recv(s,buf,PACKET_SIZE,0)==-1) break;
		
		cout << "\nClient #" << client_num << " << " << buf << "\n보낼 데이터를 입력 >> ";
	}
	
	return;
}

void accpetclients(){
	char client_num[10];
	for(int i=0;i<MAX;i++){
		client_size[i] = sizeof(client[i]);
		client_sock[i] = accept(skt,(SOCKADDR*)&client[i],&client_size[i]);
		
		if(client_sock[i]==INVALID_SOCKET){
			cout << "accept error";
			closesocket(client_sock[i]);
			closesocket(skt);
			WSACleanup();
			return;
		}
		
		cout << "Client #" << i << " Joined!" << "\n보낼 데이터를 입력 >> ";
		ZeroMemory(client_num,sizeof(client_num));
		itoa(i,client_num,10);
		send(client_sock[i],client_num,strlen(client_num),0);
		thread (recv_data,ref(client_sock[i]),i).detach();
	}
	return;
}

void openSocket(int PORT){
	if(WSAStartup(MAKEWORD(2,2), &wsa)){
		cout << "WSA error";
		return;
	}

	skt = socket(PF_INET,SOCK_STREAM,IPPROTO_TCP);
	if(skt==INVALID_SOCKET){
		cout << "socket error";
		closesocket(skt);
		WSACleanup();
		return;
	}

	SOCKADDR_IN addr = {};
	addr.sin_family = AF_INET;
	addr.sin_port = htons(PORT);
	addr.sin_addr.s_addr = htonl(INADDR_ANY);

	if(bind(skt, (SOCKADDR*)&addr,sizeof(addr))){
		cout << "bind error";
		closesocket(skt);
		WSACleanup();
		return;
	}
	if(listen(skt,SOMAXCONN)){
		cout << "listen error";
		closesocket(skt);
		WSACleanup();
		return;
	}
	
	thread (accpetclients).detach();
	
	char msg[PACKET_SIZE],sendnum[PACKET_SIZE]; 
	
	while(1){
		cout << "보낼 데이터를 입력 >> ";
		cin >> msg;
		
		if(!strcmp(msg,"exit")) break;
		
		cout << "대상 클라이언트를 입력(all:모두) >> ";
		cin >> sendnum;
		
		if(!strcmp(sendnum,"all"))
			for (int i=0;i<MAX;i++)
				send(client_sock[i],msg,strlen(msg),0);
		else send(client_sock[atoi(sendnum)],msg,strlen(msg),0);
	}

	for(int i=0;i<MAX;i++) closesocket(client_sock[i]);
	closesocket(skt);
	WSACleanup();
	return;
}

int main(){
	int PORT;
	cout << "포트설정 >> ";
	cin >> PORT;
	cout << "클라이언트 최대수용 수 설정 >> ";
	cin >> MAX;
	
	client_sock = new SOCKET[MAX];
	client = new SOCKADDR_IN[MAX];
	client_size  = new int[MAX];
	
	ZeroMemory(client_sock,sizeof(client_sock));
	ZeroMemory(client,sizeof(client));
	ZeroMemory(client_size,sizeof(client_size));
	
	openSocket(PORT);
	
	delete[] client_sock,client,client_size;
	return 0;
}