libiberty/timeval-utils.c

   1 /* Basic struct timeval utilities.
   2    Copyright (C) 2011-2019 Free Software Foundation, Inc.
   3
   4 This file is part of the libiberty library.
   5 Libiberty is free software; you can redistribute it and/or
   6 modify it under the terms of the GNU Library General Public
   7 License as published by the Free Software Foundation; either
   8 version 2 of the License, or (at your option) any later version.
   9
  10 Libiberty is distributed in the hope that it will be useful,
  11 but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13 Library General Public License for more details.
  14
  15 You should have received a copy of the GNU Library General Public
  16 License along with libiberty; see the file COPYING.LIB.  If not,
  17 write to the Free Software Foundation, Inc., 51 Franklin Street - Fifth Floor,
  18 Boston, 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
  46 Adds @var{a} to @var{b} and stores the result in @var{result}.
  47
  48 @end deftypefn
  49
  50 */
  51
  52 void
  53 timeval_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
  70 Subtracts @var{b} from @var{a} and stores the result in @var{result}.
  71
  72 @end deftypefn
  73
  74 */
  75
  76 void
  77 timeval_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 }