static enum MHD_Result handle_get(struct MHD_Connection *connection, SV url, Settings settings, SV username) {
    noh_arena_save(&temp);
    Noh_String fs_path = build_path(false, false, &settings.base_path, &username, &url);
    url_decode(&fs_path);

    noh_log(NOH_INFO, "Physical path: "Nsv_Fmt, Nsv_Arg(fs_path));

    if (!noh_sv_ends_with(noh_sv_from_string(fs_path), sv(".epub"))) {
        return send_response(connection, 400, sv("File is not an epub file."), false);
    }

    noh_string_append_null(&fs_path);

    // Try to open the file.
    FILE *file = fopen(fs_path.elems, "r");
    if (file == NULL) {
        if (errno == ENOENT) {
            noh_arena_reset(&temp);
            return send_response(connection, 404, sv("File does not exist."), false);
        } else {
            noh_log(NOH_ERROR, "Opening file failed.");
            noh_arena_reset(&temp);
            return send_response(connection, 500, sv(""), false);
        }
    }

    fseek(file, 0L, SEEK_END);
    size_t file_size = ftell(file);
    fseek(file, 0L, SEEK_SET);
    return send_epub_file(connection, fileno(file), file_size);
}