server.c

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>

#define MAX_CLIENTS 2
#define BUFFER_SIZE 2048
#define DEFAULT_PORT 25555

typedef struct {
    int socket;
    char name[50];
    int score;
    int answered;
    char answer[BUFFER_SIZE];
} Player;

Player players[MAX_CLIENTS];

void trim_newline(char *s) {
    s[strcspn(s, "\n")] = 0;
}

int main(int argc, char *argv[]) {
    int server_fd, port = DEFAULT_PORT;
    struct sockaddr_in address;
    socklen_t addrlen = sizeof(address);

    FILE *qfile = fopen("questions.txt", "r");
    if (!qfile) {
        perror("Failed to open questions file");
        return 1;
    }

    server_fd = socket(AF_INET, SOCK_STREAM, 0);
    if (server_fd < 0) {
        perror("Socket failed");
        return 1;
    }

    address.sin_family = AF_INET;
    address.sin_addr.s_addr = INADDR_ANY;
    address.sin_port = htons(port);

    if (bind(server_fd, (struct sockaddr *)&address, sizeof(address)) < 0) {
        perror("Bind failed");
        return 1;
    }

    if (listen(server_fd, MAX_CLIENTS) < 0) {
        perror("Listen failed");
        return 1;
    }

    printf("Server started on port %d\n", port);

    for (int i = 0; i < MAX_CLIENTS; i++) {
        players[i].socket = accept(server_fd, (struct sockaddr *)&address, &addrlen);
        players[i].score = 0;
        players[i].answered = 0;

        send(players[i].socket, "Enter your name: ", 17, 0);
        recv(players[i].socket, players[i].name, sizeof(players[i].name), 0);
        trim_newline(players[i].name);

        printf("Player connected: %s\n", players[i].name);
    }

    char question[BUFFER_SIZE], options[BUFFER_SIZE], correct[BUFFER_SIZE];

    while (fgets(question, sizeof(question), qfile)) {
        fgets(options, sizeof(options), qfile);
        fgets(correct, sizeof(correct), qfile);
        trim_newline(correct);

        char msg[BUFFER_SIZE];
        snprintf(msg, sizeof(msg), "\n%s%s\n", question, options);

        for (int i = 0; i < MAX_CLIENTS; i++) {
            send(players[i].socket, msg, strlen(msg), 0);
            players[i].answered = 0;
        }

        for (int i = 0; i < MAX_CLIENTS; i++) {
            recv(players[i].socket, players[i].answer, sizeof(players[i].answer), 0);
            trim_newline(players[i].answer);
            players[i].answered = 1;

            if (strcmp(players[i].answer, correct) == 0) {
                players[i].score++;
            }
        }

        for (int i = 0; i < MAX_CLIENTS; i++) {
            snprintf(msg, sizeof(msg),
                     "\nScores:\n%s: %d\n%s: %d\n",
                     players[0].name, players[0].score,
                     players[1].name, players[1].score);
            send(players[i].socket, msg, strlen(msg), 0);
        }

        fgets(question, sizeof(question), qfile); // consume blank line
    }

    for (int i = 0; i < MAX_CLIENTS; i++) {
        close(players[i].socket);
    }

    fclose(qfile);
    close(server_fd);
    return 0;
}