Code winsock2 chạy được server nhưng client không thể kết nối đến server

#1

Em đang tìm hiểu về web socket sử dụng C++ và thư viên Winsock2. Khi chạy chương trình em thấy server thì chạy được nhưng client lại không thể kết nối đến server này ạ anh chị xem giúp em với ạ. Em cảm ơn!!
Đây là code Server:

#include <winsock2.h>
#include <ws2tcpip.h>
#include <string>
#include <thread>
#include <vector>
#include <cstdlib>

using namespace std;

#pragma comment (lib, "Ws2_32.lib")

#define IP_ADDRESS "10.2.32.74"
#define DEFAULT_PORT "3504"
#define DEFAULT_BUFLEN 512

struct client_type
{
	int id;
	SOCKET socket;
};

const char OPTION_VALUE = 1;
const int MAX_CLIENTS = 1;

//Function Prototypes
//int main();

int process_client(client_type &new_client, vector<client_type> &client_array, thread &thread)
{
	string msg = "";
	char tempmsg[DEFAULT_BUFLEN] = "";

	//Session
	while (1)
	{
		memset(tempmsg, 0, DEFAULT_BUFLEN);

		if (new_client.socket != 0)
		{
			int iResult = recv(new_client.socket, tempmsg, DEFAULT_BUFLEN, 0);

			if (iResult != SOCKET_ERROR)
			{
				if (strcmp("", tempmsg))
					msg = "Client #" + to_string(new_client.id) + ": " + tempmsg;

				cout << msg.c_str() << endl;

				//Broadcast that message to the other clients
				for (int i = 0; i < MAX_CLIENTS; i++)
				{
					if (client_array[i].socket != INVALID_SOCKET)
						if (new_client.id != i)
							iResult = send(client_array[i].socket, msg.c_str(), strlen(msg.c_str()), 0);
				}
			}
			else
			{
				msg = "Client #" + to_string(new_client.id) + " Disconnected";

				cout << msg << std::endl;

				closesocket(new_client.socket);
				closesocket(client_array[new_client.id].socket);
				client_array[new_client.id].socket = INVALID_SOCKET;

				//Broadcast the disconnection message to the other clients
				for (int i = 0; i < MAX_CLIENTS; i++)
				{
					if (client_array[i].socket != INVALID_SOCKET)
						iResult = send(client_array[i].socket, msg.c_str(), strlen(msg.c_str()), 0);
				}

				break;
			}
		}
	} //end while

	thread.detach();

	return 0;
}

int main()
{
	WSADATA wsaData;
	int iResult;
	string sResult;
	struct addrinfo hints;
	struct addrinfo *server = NULL;
	SOCKET server_socket = INVALID_SOCKET;
	std::string msg = "";
	std::vector<client_type> client(MAX_CLIENTS);
	int num_clients = 0;
	int temp_id = -1;
	std::thread my_thread[MAX_CLIENTS];

	//Initialize Winsock
	cout << "Intializing Winsock..." << std::endl;
	iResult = WSAStartup(MAKEWORD(2, 2), &wsaData);
	if (iResult != 0)
	{
		cout << "failed" << iResult << endl;
		return 1;
	}

	//Setup hints
	ZeroMemory(&hints, sizeof(hints));
	hints.ai_family = AF_INET;
	hints.ai_socktype = SOCK_STREAM;
	hints.ai_protocol = IPPROTO_TCP;
	hints.ai_flags = AI_PASSIVE;

	//Setup Server
	cout << "Setting up server..." << endl;	
	iResult = getaddrinfo(static_cast<LPCTSTR>(IP_ADDRESS), DEFAULT_PORT, &hints, &server);
	if (iResult != 0)
	{
		cout << "failed with error" << iResult << endl;
		WSACleanup();
		return 1;
	}
		
	//Create a listening socket for connecting to server
	std::cout << "Creating server socket..." << std::endl;	
	server_socket = socket(server->ai_family, server->ai_socktype, server->ai_protocol);
	if (server_socket == INVALID_SOCKET) {
		cout << "error" << WSAGetLastError() << endl;
		freeaddrinfo(server);
		closesocket(server_socket);
		WSACleanup();
		return 1;
	}
	

	//Setup socket options
	setsockopt(server_socket, SOL_SOCKET, SO_REUSEADDR, &OPTION_VALUE, sizeof(int)); //Make it possible to re-bind to a port that was used within the last 2 minutes
	setsockopt(server_socket, IPPROTO_TCP, TCP_NODELAY, &OPTION_VALUE, sizeof(int)); //Used for interactive programs

	//Assign an address to the server socket.
	std::cout << "Binding socket..." << std::endl;
	bind(server_socket, server->ai_addr, (int)server->ai_addrlen);

	//Listen for incoming connections.
	std::cout << "Listening..." << std::endl;
	listen(server_socket, SOMAXCONN);
	/*if (listen(server_socket, SOMAXCONN) == SOCKET_ERROR)
	{
		cout << "listen failed" << WSAGetLastError() << endl;
		closesocket(server_socket);
		WSACleanup();
		return 1;
	}*/

	//Initialize the client list
	for (int i = 0; i < MAX_CLIENTS; i++)
	{
		client[i] = { -1, INVALID_SOCKET };
	}

	while (1)
	{

		SOCKET incoming = INVALID_SOCKET;
		incoming = accept(server_socket, NULL, NULL);

		if (incoming == INVALID_SOCKET) continue;

		//Reset the number of clients
		num_clients = -1;

		//Create a temporary id for the next client
		temp_id = -1;
		for (int i = 0; i < MAX_CLIENTS; i++)
		{
			if (client[i].socket == INVALID_SOCKET && temp_id == -1)
			{
				client[i].socket = incoming;
				client[i].id = i;
				temp_id = i;
			}

			if (client[i].socket != INVALID_SOCKET)
				num_clients++;

			//std::cout << client[i].socket << std::endl;
		}

		if (temp_id != -1)
		{
			//Send the id to that client
			std::cout << "Client #" << client[temp_id].id << " Accepted" << std::endl;
			msg = std::to_string(client[temp_id].id);
			send(client[temp_id].socket, msg.c_str(), strlen(msg.c_str()), 0);

			//Create a thread process for that client
			my_thread[temp_id] = std::thread(process_client, std::ref(client[temp_id]), std::ref(client), std::ref(my_thread[temp_id]));
		}
		else
		{
			msg = "Server is full";
			send(incoming, msg.c_str(), strlen(msg.c_str()), 0);
			std::cout << msg << std::endl;
		}
	} //end while


	//Close listening socket
	closesocket(server_socket);

	//Close client socket
	for (int i = 0; i < MAX_CLIENTS; i++)
	{
		my_thread[i].detach();
		closesocket(client[i].socket);
	}

	//Clean up Winsock
	WSACleanup();
	std::cout << "Program has ended successfully" << std::endl;
	

	//system("pause");
	return 0;
}```

Đây là code client:
```#include <winsock2.h>
#include <ws2tcpip.h>
#include <iostream>
#include <string>
#include <thread>

using namespace std;

#pragma comment (lib, "Ws2_32.lib")

#define DEFAULT_BUFLEN 512            
#define IP_ADDRESS "10.2.32.74"
#define DEFAULT_PORT "3504"

struct client_type
{
	SOCKET socket;
	int id;
	char received_message[DEFAULT_BUFLEN];
};


int process_client(client_type &new_client)
{
	while (1)
	{
		memset(new_client.received_message, 0, DEFAULT_BUFLEN);

		if (new_client.socket != 0)
		{
			int iResult = recv(new_client.socket, new_client.received_message, DEFAULT_BUFLEN, 0);

			if (iResult != SOCKET_ERROR)
				cout << new_client.received_message << endl;
			else
			{
				cout << "recv() failed: " << WSAGetLastError() << endl;
				break;
			}
		}
	}

	if (WSAGetLastError() == WSAECONNRESET)
		cout << "The server has disconnected" << endl;

	return 0;
}

int main()
{
	//thread(client_type, );
	WSAData wsa_data;
	struct addrinfo *result = NULL, *ptr = NULL, hints;
	string sent_message = "";
	client_type client = { INVALID_SOCKET, -1, "" };
	int iResult = 0;
	string message;

	cout << "Starting Client...\n";

	// Initialize Winsock
	iResult = WSAStartup(MAKEWORD(2, 2), &wsa_data);
	if (iResult != 0) {
		cout << "WSAStartup() failed with error: " << iResult << endl;
		return 1;
	}

	ZeroMemory(&hints, sizeof(hints));
	hints.ai_family = AF_UNSPEC;
	hints.ai_socktype = SOCK_STREAM;
	hints.ai_protocol = IPPROTO_TCP;

	cout << "Connecting...\n";

	// Resolve the server address and port
	iResult = getaddrinfo(static_cast<LPCTSTR>(IP_ADDRESS), DEFAULT_PORT, &hints, &result);
	if (iResult != 0) {
		cout << "getaddrinfo() failed with error: " << iResult << endl;
		WSACleanup();
		system("pause");
		return 1;
	}

	// Attempt to connect to an address until one succeeds
	for (ptr = result; ptr != NULL; ptr = ptr->ai_next) {

		// Create a SOCKET for connecting to server
		client.socket = socket(ptr->ai_family, ptr->ai_socktype, ptr->ai_protocol);
		if (client.socket == INVALID_SOCKET) {
			cout << "socket() failed with error: " << WSAGetLastError() << endl;
			WSACleanup();
			system("pause");
			return 1;
		}

		// Connect to server.		
		iResult = connect(client.socket, ptr->ai_addr, (int)ptr->ai_addrlen);
		//cout << iResult << endl;
		//system("pause");
		//cout << ptr<<endl;
		if (iResult == SOCKET_ERROR) {
			//closesocket(client.socket);
			iResult = connect(client.socket, ptr->ai_addr, (int)ptr->ai_addrlen);
			//cout<< WSAGetLastError() <<endl;
			//cout << SOCKET_ERROR << endl;
			client.socket = INVALID_SOCKET;
			//continue;
		}
		//break;
	}

	freeaddrinfo(result);

	if (client.socket == INVALID_SOCKET) {
		//cout << INVALID_SOCKET << endl;
		cout << "Unable to connect to server!" /*<<"\n"<< WSAGetLastError()*/ << endl;
		WSACleanup();
		system("pause");
		return 1;
	}

	cout << "Successfully Connected" << endl;

	//Obtain id from server for this client;
	recv(client.socket, client.received_message, DEFAULT_BUFLEN, 0);
	message = client.received_message;

	if (message != "Server is full")
	{
		client.id = atoi(client.received_message);

		thread my_thread(process_client, ref(client));

		while (1)
		{
			getline(cin, sent_message);
			iResult = send(client.socket, sent_message.c_str(), strlen(sent_message.c_str()), 0);

			if (iResult <= 0)
			{
				cout << "send() failed: " << WSAGetLastError() << endl;
				break;
			}
		}

		//Shutdown the connection since no more data will be sent
		my_thread.detach();
	}
	else
		cout << client.received_message << endl;

	cout << "Shutting down socket..." << endl;
	iResult = shutdown(client.socket, SD_SEND);
	if (iResult == SOCKET_ERROR) {
		cout << "shutdown() failed with error: " << WSAGetLastError() << endl;
		closesocket(client.socket);
		WSACleanup();
		system("pause");
		return 1;
	}

	closesocket(client.socket);
	WSACleanup();
	system("pause");
	return 0;
}```
#2

Đây đâu phải websocket đâu. Chỉ là chương trình giao tiếp cơ bản c-s thôi

Thử chạy nó báo gì hả b?

1 Like
#3

Cái client không kết nối được đến cái server:
unable connect to server

Cái server thì vẫn chạy được

#4

Cái ip kia có chắc chắn là đúng interface mạng ko?

#5

Anh có thể thay bằng ip của anh mà

83% thành viên diễn đàn không hỏi bài tập, còn bạn thì sao?