jcs.org
Serenity Operating System
1/*
2 * Copyright (c) 2020, Nico Weber <thakis@chromium.org>
3 * Copyright (c) 2022, Matthias Zimmerman <matthias291999@gmail.com>
4 *
5 * SPDX-License-Identifier: BSD-2-Clause
6 */
7
8#include <LibCore/ArgsParser.h>
9#include <LibCore/System.h>
10#include <math.h>
11#include <sys/time.h>
12#include <unistd.h>
13
14ErrorOr<int> serenity_main(Main::Arguments arguments)
15{
16 TRY(Core::System::pledge("stdio settime"));
17
18 Core::ArgsParser args_parser;
19 Optional<double> delta;
20 args_parser.add_option(delta, "Adjust system time by this many seconds", "set", 's', "delta_seconds");
21 args_parser.parse(arguments);
22
23 if (delta.has_value()) {
24 long delta_us = static_cast<long>(round(*delta * 1'000'000));
25 timeval delta_timeval;
26 delta_timeval.tv_sec = delta_us / 1'000'000;
27 delta_timeval.tv_usec = delta_us % 1'000'000;
28 if (delta_timeval.tv_usec < 0) {
29 delta_timeval.tv_sec--;
30 delta_timeval.tv_usec += 1'000'000;
31 }
32 TRY(Core::System::adjtime(&delta_timeval, nullptr));
33 }
34
35 TRY(Core::System::pledge("stdio"));
36
37 timeval remaining_delta_timeval;
38 TRY(Core::System::adjtime(nullptr, &remaining_delta_timeval));
39 double remaining_delta = remaining_delta_timeval.tv_sec + remaining_delta_timeval.tv_usec / 1'000'000.0;
40 outln("{}", remaining_delta);
41
42 return 0;
43}