mirror of
https://sourceware.org/git/glibc.git
synced 2024-11-30 08:40:07 +00:00
76 lines
2.5 KiB
C
76 lines
2.5 KiB
C
/* Sleep for a given number of seconds. POSIX.1 version.
|
|
Copyright (C) 1991-2012 Free Software Foundation, Inc.
|
|
This file is part of the GNU C Library.
|
|
|
|
The GNU C Library is free software; you can redistribute it and/or
|
|
modify it under the terms of the GNU Lesser General Public
|
|
License as published by the Free Software Foundation; either
|
|
version 2.1 of the License, or (at your option) any later version.
|
|
|
|
The GNU C Library is distributed in the hope that it will be useful,
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
Lesser General Public License for more details.
|
|
|
|
You should have received a copy of the GNU Lesser General Public
|
|
License along with the GNU C Library; if not, see
|
|
<http://www.gnu.org/licenses/>. */
|
|
|
|
#include <time.h>
|
|
#include <unistd.h>
|
|
#include <errno.h>
|
|
#include <sys/param.h>
|
|
|
|
|
|
/* Make the process sleep for SECONDS seconds, or until a signal arrives
|
|
and is not ignored. The function returns the number of seconds less
|
|
than SECONDS which it actually slept (zero if it slept the full time).
|
|
If a signal handler does a `longjmp' or modifies the handling of the
|
|
SIGALRM signal while inside `sleep' call, the handling of the SIGALRM
|
|
signal afterwards is undefined. There is no return value to indicate
|
|
error, but if `sleep' returns SECONDS, it probably didn't work. */
|
|
unsigned int
|
|
__sleep (unsigned int seconds)
|
|
{
|
|
/* This is not necessary but some buggy programs depend on it. */
|
|
if (__builtin_expect (seconds == 0, 0))
|
|
{
|
|
#ifdef CANCELLATION_P
|
|
CANCELLATION_P (THREAD_SELF);
|
|
#endif
|
|
return 0;
|
|
}
|
|
|
|
int save_errno = errno;
|
|
|
|
const unsigned int max
|
|
= (unsigned int) (((unsigned long int) (~((time_t) 0))) >> 1);
|
|
struct timespec ts = { 0, 0 };
|
|
do
|
|
{
|
|
if (sizeof (ts.tv_sec) <= sizeof (seconds))
|
|
{
|
|
/* Since SECONDS is unsigned assigning the value to .tv_sec can
|
|
overflow it. In this case we have to wait in steps. */
|
|
ts.tv_sec += MIN (seconds, max);
|
|
seconds -= (unsigned int) ts.tv_sec;
|
|
}
|
|
else
|
|
{
|
|
ts.tv_sec = (time_t) seconds;
|
|
seconds = 0;
|
|
}
|
|
|
|
if (__nanosleep (&ts, &ts) < 0)
|
|
/* We were interrupted.
|
|
Return the number of (whole) seconds we have not yet slept. */
|
|
return seconds + ts.tv_sec;
|
|
}
|
|
while (seconds > 0);
|
|
|
|
__set_errno (save_errno);
|
|
|
|
return 0;
|
|
}
|
|
weak_alias (__sleep, sleep)
|