1/* Basic struct timeval utilities.
2   Copyright (C) 2011 Free Software Foundation, Inc.
3
4This file is part of the libiberty library.
5Libiberty is free software; you can redistribute it and/or
6modify it under the terms of the GNU Library General Public
7License as published by the Free Software Foundation; either
8version 2 of the License, or (at your option) any later version.
9
10Libiberty is distributed in the hope that it will be useful,
11but WITHOUT ANY WARRANTY; without even the implied warranty of
12MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13Library General Public License for more details.
14
15You should have received a copy of the GNU Library General Public
16License along with libiberty; see the file COPYING.LIB.  If not,
17write to the Free Software Foundation, Inc., 51 Franklin Street - Fifth Floor,
18Boston, MA 02110-1301, USA.  */
19
20#include "config.h"
21
22/* On some systems (such as WindISS), you must include <sys/types.h>
23   to get the definition of "time_t" before you include <time.h>.  */
24#include <sys/types.h>
25
26#ifdef TIME_WITH_SYS_TIME
27# include <sys/time.h>
28# include <time.h>
29#else
30# if HAVE_SYS_TIME_H
31#  include <sys/time.h>
32# else
33#  ifdef HAVE_TIME_H
34#   include <time.h>
35#  endif
36# endif
37#endif
38
39#include "timeval-utils.h"
40
41/*
42
43@deftypefn Extension void timeval_add (struct timeval *@var{a}, @
44  struct timeval *@var{b}, struct timeval *@var{result})
45
46Adds @var{a} to @var{b} and stores the result in @var{result}.
47
48@end deftypefn
49
50*/
51
52void
53timeval_add (struct timeval *result,
54	     const struct timeval *a, const struct timeval *b)
55{
56  result->tv_sec = a->tv_sec + b->tv_sec;
57  result->tv_usec = a->tv_usec + b->tv_usec;
58  if (result->tv_usec >= 1000000)
59    {
60      ++result->tv_sec;
61      result->tv_usec -= 1000000;
62    }
63}
64
65/*
66
67@deftypefn Extension void timeval_sub (struct timeval *@var{a}, @
68  struct timeval *@var{b}, struct timeval *@var{result})
69
70Subtracts @var{b} from @var{a} and stores the result in @var{result}.
71
72@end deftypefn
73
74*/
75
76void
77timeval_sub (struct timeval *result,
78	     const struct timeval *a, const struct timeval *b)
79{
80  result->tv_sec = a->tv_sec - b->tv_sec;
81  result->tv_usec = a->tv_usec - b->tv_usec;
82  if (result->tv_usec < 0)
83    {
84      --result->tv_sec;
85      result->tv_usec += 1000000;
86    }
87}
88