1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
|
/*
* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <LibCore/ArgsParser.h>
#include <errno.h>
#include <signal.h>
#include <stdio.h>
#include <string.h>
#include <time.h>
#include <unistd.h>
static volatile bool g_interrupted;
static void handle_sigint(int)
{
g_interrupted = true;
}
int main(int argc, char** argv)
{
double secs;
Core::ArgsParser args_parser;
args_parser.add_positional_argument(secs, "Number of seconds to sleep for", "num-seconds");
args_parser.parse(argc, argv);
struct sigaction sa;
memset(&sa, 0, sizeof(struct sigaction));
sa.sa_handler = handle_sigint;
sigaction(SIGINT, &sa, nullptr);
if (pledge("stdio sigaction", nullptr) < 0) {
perror("pledge");
return 1;
}
double whole_seconds = static_cast<time_t>(secs);
double fraction = secs - whole_seconds;
timespec requested_sleep {
.tv_sec = static_cast<time_t>(whole_seconds),
.tv_nsec = static_cast<long>(fraction * (double)1000000000),
};
timespec remaining_sleep {};
sleep_again:
if (clock_nanosleep(CLOCK_MONOTONIC, 0, &requested_sleep, &remaining_sleep) < 0) {
if (errno != EINTR) {
perror("clock_nanosleep");
return 1;
}
}
if (remaining_sleep.tv_sec || remaining_sleep.tv_nsec) {
if (!g_interrupted) {
// If not interrupted with SIGINT, just go back to sleep.
requested_sleep = remaining_sleep;
goto sleep_again;
}
outln("Sleep interrupted with {}.{} seconds remaining.", remaining_sleep.tv_sec, remaining_sleep.tv_nsec);
}
signal(SIGINT, SIG_DFL);
if (g_interrupted)
raise(SIGINT);
return 0;
}
|
