where-are-my-friends/src/main.c

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>

#include "rcon.h"

const char *LOCALHOST = "127.0.0.1";

int read_env_int(const char *var) {
    const char* port_str = getenv(var);
    if (port_str == NULL) {
        fprintf(stderr, "error: %s environment variable not set.\n", var);
        exit(EXIT_FAILURE);
    }
    char* endptr;
    long val = strtol(port_str, &endptr, 10);
    if (endptr == port_str || *endptr != '\0') {
        fprintf(stderr, "error: invalid number format for %s.\n", var);
        exit(EXIT_FAILURE);
    }
    return (int)val;
}

int main(void) {
    const int PORT_NUM = read_env_int("RCON_PORT_NUMBER");
    const char *password = getenv("RCON_PASSWORD");

    if (password == NULL) {
        fprintf(stderr, "error: RCON_PASSWORD environment variable not set.\n");
        exit(EXIT_FAILURE);
    }

    printf("=== RCON Configuration ===\n");
    printf("port: %d\n", PORT_NUM);
    printf("password: '%s'\n", password);
    printf("==========================\n\n");

    int sockfd = rcon_connect(LOCALHOST, PORT_NUM);

    if (rcon_authenticate(sockfd, password) < 0) {
        close(sockfd);
        exit(EXIT_FAILURE);
    }

    const char *get_player_positions_cmd = "execute as @a run data get entity @s Pos";
    printf("\nexecuting command: %s\n", get_player_positions_cmd);
    char *response = rcon_command_multipacket(sockfd, get_player_positions_cmd);

    if (response) {
        printf("\n=== player positions ===\n");
        printf("%s\n", response);
    } else {
        fprintf(stderr, "failed to get player positions\n");
    }

    close(sockfd);
    return 0;
}