[Feature] working client and server

109062273_cli.cpp

@@ -0,0 +1,112 @@
+#include <iostream>
+#include <sstream>
+#include <string>
+#include <cstring>
+#include <cstdlib>
+#include <sys/socket.h>
+#include <sys/types.h>
+#include <netinet/in.h>
+#include <arpa/inet.h>
+
+#define BUFFER_SIZE 256
+#define NOSERVER_RET 10
+#define INVALID_PORT_RET 20
+#define CONN_FAILED_RET 30
+
+using namespace std;
+
+int main(int argc, char const *argv[]) {
+    // no server info specified
+    if (argc < 2) {
+        cerr << "No server info provided!" << endl << "Usage: client <ip> <port>" << endl;
+        return NOSERVER_RET;
+    }
+
+    int port = atoi(argv[2]);
+    if (port < 0 || port >= 65536) {
+        cerr << "Invalid port! port range: 0 ~ 65535" << endl;
+        return INVALID_PORT_RET;
+    }
+
+    int sockfd = 0;
+    struct sockaddr_in info;
+
+    // create tcp socket
+    sockfd = socket(AF_INET, SOCK_STREAM, 0);
+    if (sockfd == -1) {
+        cerr << "Failed to create socket." << endl;
+    }
+
+    // setup server info
+    bzero(&info, sizeof(info));
+    info.sin_family = PF_INET;
+    info.sin_addr.s_addr = inet_addr(argv[1]);
+    info.sin_port = htons(port);
+
+    if (connect(sockfd, (struct sockaddr *) &info, sizeof(info)) == -1) {
+        cerr << "Connection failed." << endl;
+        return CONN_FAILED_RET;
+    }
+
+    cout << "--------------" << endl;
+    cout << "  Game start  " << endl;
+    cout << "--------------" << endl;
+
+    while (true) {
+        // ask for input
+        cout << "Guess: ";
+        string number;
+        cin >> number;
+
+        // create payload
+        const char * msg = number.c_str();
+
+        #ifdef DEBUG
+        cout << msg << endl;
+        #endif
+
+        if (send(sockfd, msg, sizeof(msg), 0) == -1) {
+            cerr << "Send error" << endl;
+            break;
+        };
+
+        // receive server response
+        char buffer[BUFFER_SIZE] = {0};
+        int size = recv(sockfd, buffer, sizeof(buffer), 0);
+        if (size <= 0) {
+            cout << "Connection ended." << endl;
+            break;
+        }
+
+        #ifdef DEBUG
+        cout << buffer << endl;
+        #endif
+
+        // parse message from server
+        stringstream ss(buffer);
+        string lower, upper, count;
+        getline(ss, lower, ':');
+        getline(ss, upper, ':');
+        getline(ss, count, ':');
+
+        if (lower == upper) {
+            // win, start new turn
+            cout << "Answer Correct. Guessed for " << count << " times." << endl;
+            cout << endl;
+            cout << "--------------" << endl;
+            cout << "   New Turn   " << endl;
+            cout << "--------------" << endl;
+            continue;
+        }
+
+        if (count != "0") {
+            cout << "Answer is fewer than " << upper << endl;
+            cout << "Answer is more than " << lower << endl;
+        }
+
+        // space
+        cout << endl;
+    }
+
+    return 0;
+}

109062273_ser.cpp

@@ -0,0 +1,177 @@
+#include <iostream>
+#include <sstream>
+#include <string>
+#include <cstring>
+#include <cstdlib>
+#include <ctime>
+#include <sys/socket.h>
+#include <sys/types.h>
+#include <netinet/in.h>
+#include <arpa/inet.h>
+
+#define BUFFER_SIZE 256
+#define NOPORT_RET 10
+#define INVALID_PORT_RET 20
+#define BINDERR_RET 30
+#define LISTENERR_RET 35
+
+using namespace std;
+
+class Game {
+    private:
+        int upper;
+        int lower;
+        int count;
+        int answer;
+    public:
+        Game(void) {
+            this->reset();
+        }
+
+        int get_upper() {
+            return this->upper;
+        }
+
+        int get_lower() {
+            return this->lower;
+        }
+
+        int get_count() {
+            return this->count;
+        }
+
+        int get_answer() {
+            return this->answer;
+        }
+
+        void reset() {
+            this->upper = 999;
+            this->lower = 0;
+            this->count = 0;
+            this->answer = rand() % 1000;
+        }
+
+        bool guess(int num) {
+            this->count++;
+            if (num == answer) return true;
+
+            if (num > answer && num < this->upper) this->upper = num;
+            else if (num < answer && num > this->lower) this->lower = num;
+
+            return false;
+        }
+};
+
+int main(int argc, char const *argv[]) {
+    // initialize game
+    srand(time(nullptr));
+    Game game;
+
+    // no port specified
+    if (argc < 1) {
+        cerr << "No port provided!" << endl << "Usage: server <port>" << endl;
+        return NOPORT_RET;
+    }
+
+    int port = atoi(argv[1]);
+    if (port < 0 || port >= 65536) {
+        cerr << "Invalid port! port range: 0 ~ 65535" << endl;
+        return INVALID_PORT_RET;
+    }
+
+    int sockfd = 0;
+    struct sockaddr_in server_info;
+
+    // create tcp socket
+    sockfd = socket(AF_INET, SOCK_STREAM, 0);
+    if (sockfd == -1) {
+        cerr << "Failed to create socket" << endl;
+    }
+
+    // setup server info
+    bzero((char *) &server_info, sizeof(server_info));
+    server_info.sin_family = PF_INET;
+    server_info.sin_addr.s_addr = INADDR_ANY;
+    server_info.sin_port = htons(port);
+
+    // bind
+    if (bind(sockfd, (struct sockaddr *) &server_info, sizeof(server_info)) == -1) {
+        cerr << "Cannot bind server." << endl;
+        return BINDERR_RET;
+    }
+
+    // only one connection at the same time
+    if (listen(sockfd, 1) == -1) {
+        cerr << "Cannot listen socket." << endl;
+        return LISTENERR_RET;
+    }
+    cout << "Server up. Waiting connection..." << endl;
+
+    int client_sockfd = 0;
+    struct sockaddr_in client_info;
+    socklen_t addrlen = sizeof(client_info);
+
+    while (true) {
+        client_sockfd = accept(sockfd, (struct sockaddr *) &client_info, &addrlen);
+        if (client_sockfd < 0) {
+            cout << "Error occurred while handling request from client." << endl;
+            continue;
+        }
+
+        // retrieve client info
+        char ip[INET_ADDRSTRLEN];
+        uint16_t port;
+        inet_ntop(AF_INET, &client_info.sin_addr, ip, sizeof(ip));
+        port = ntohs(client_info.sin_port);
+
+        cout << "New client from " << ip << ":" << port << " has connected!" << endl;
+
+        // reset for new client
+        game.reset();
+
+        while (true) {
+            // clear buffer for receive message
+            char buffer[BUFFER_SIZE];
+            memset(buffer, 0, sizeof(buffer));
+
+            // wait message
+            if (recv(client_sockfd, buffer, sizeof(buffer), 0) <= 0) {
+                // closed connection
+                cout << "Disconnected." << endl;
+                break;
+            }
+
+            int guess = atoi(buffer);
+
+            #ifdef DEBUG
+            cout << guess << endl;
+            #endif
+
+            // message
+            stringstream ss;
+            const char * msg;
+
+            #ifdef DEBUG
+            cout << msg << endl;
+            #endif
+
+            // generate payload
+            if (game.guess(guess)) {
+                // win
+                ss << game.get_answer() << ":" << game.get_answer() << ":" << game.get_count();
+
+                // new turn for this client
+                game.reset();
+            } else {
+                ss << game.get_lower() << ":" << game.get_upper() << ":" << game.get_count();
+            }
+
+            msg = ss.str().c_str();
+
+            // send to client
+            send(client_sockfd, msg, strlen(msg), 0);
+        }
+    }
+
+    return 0;
+}