1/* ufuncs - sleep and alarm functions that understand fractional values */
2
3/* Copyright (C) 2008,2009 Free Software Foundation, Inc.
4
5   This file is part of GNU Bash, the Bourne Again SHell.
6
7   Bash is free software: you can redistribute it and/or modify
8   it under the terms of the GNU General Public License as published by
9   the Free Software Foundation, either version 3 of the License, or
10   (at your option) any later version.
11
12   Bash is distributed in the hope that it will be useful,
13   but WITHOUT ANY WARRANTY; without even the implied warranty of
14   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15   GNU General Public License for more details.
16
17   You should have received a copy of the GNU General Public License
18   along with Bash.  If not, see <http://www.gnu.org/licenses/>.
19*/
20
21#include "config.h"
22
23#include "bashtypes.h"
24
25#if defined (TIME_WITH_SYS_TIME)
26#  include <sys/time.h>
27#  include <time.h>
28#else
29#  if defined (HAVE_SYS_TIME_H)
30#    include <sys/time.h>
31#  else
32#    include <time.h>
33#  endif
34#endif
35
36#if defined (HAVE_UNISTD_H)
37#include <unistd.h>
38#endif
39
40/* A version of `alarm' using setitimer if it's available. */
41
42#if defined (HAVE_SETITIMER)
43unsigned int
44falarm(secs, usecs)
45     unsigned int secs, usecs;
46{
47  struct itimerval it, oit;
48
49  it.it_interval.tv_sec = 0;
50  it.it_interval.tv_usec = 0;
51
52  it.it_value.tv_sec = secs;
53  it.it_value.tv_usec = usecs;
54
55  if (setitimer(ITIMER_REAL, &it, &oit) < 0)
56    return (-1);		/* XXX will be converted to unsigned */
57
58  /* Backwards compatibility with alarm(3) */
59  if (oit.it_value.tv_usec)
60    oit.it_value.tv_sec++;
61  return (oit.it_value.tv_sec);
62}
63#else
64int
65falarm (secs, usecs)
66     unsigned int secs, usecs;
67{
68  if (secs == 0 && usecs == 0)
69    return (alarm (0));
70
71  if (secs == 0 || usecs >= 500000)
72    {
73      secs++;
74      usecs = 0;
75    }
76  return (alarm (secs));
77}
78#endif /* !HAVE_SETITIMER */
79
80/* A version of sleep using fractional seconds and select.  I'd like to use
81   `usleep', but it's already taken */
82
83#if defined (HAVE_TIMEVAL) && defined (HAVE_SELECT)
84int
85fsleep(sec, usec)
86     unsigned int sec, usec;
87{
88  struct timeval tv;
89
90  tv.tv_sec = sec;
91  tv.tv_usec = usec;
92
93  return select(0, (fd_set *)0, (fd_set *)0, (fd_set *)0, &tv);
94}
95#else /* !HAVE_TIMEVAL || !HAVE_SELECT */
96int
97fsleep(sec, usec)
98     long sec, usec;
99{
100  if (usec >= 500000)	/* round */
101   sec++;
102  return (sleep(sec));
103}
104#endif /* !HAVE_TIMEVAL || !HAVE_SELECT */
105