1 /***************************************************************************
2 * Copyright (C) 2006 by Dominic Rath *
3 * Dominic.Rath@gmx.de *
5 * This program is free software; you can redistribute it and/or modify *
6 * it under the terms of the GNU General Public License as published by *
7 * the Free Software Foundation; either version 2 of the License, or *
8 * (at your option) any later version. *
10 * This program 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 *
13 * GNU General Public License for more details. *
15 * You should have received a copy of the GNU General Public License *
16 * along with this program; if not, write to the *
17 * Free Software Foundation, Inc., *
18 * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. *
19 ***************************************************************************/
22 #include "time_support.h"
27 int timeval_subtract(struct timeval *result, struct timeval *x, struct timeval *y);
28 int timeval_add(struct timeval *result, struct timeval *x, struct timeval *y);
29 int timeval_add_time(struct timeval *result, int sec, int usec);
31 /* calculate difference between two struct timeval values */
32 int timeval_subtract(struct timeval *result, struct timeval *x, struct timeval *y)
34 if (x->tv_usec < y->tv_usec)
36 int nsec = (y->tv_usec - x->tv_usec) / 1000000 + 1;
37 y->tv_usec -= 1000000 * nsec;
40 if (x->tv_usec - y->tv_usec > 1000000) {
41 int nsec = (x->tv_usec - y->tv_usec) / 1000000;
42 y->tv_usec += 1000000 * nsec;
46 result->tv_sec = x->tv_sec - y->tv_sec;
47 result->tv_usec = x->tv_usec - y->tv_usec;
49 /* Return 1 if result is negative. */
50 return x->tv_sec < y->tv_sec;
53 /* add two struct timeval values */
54 int timeval_add(struct timeval *result, struct timeval *x, struct timeval *y)
56 result->tv_sec = x->tv_sec + y->tv_sec;
58 result->tv_usec = x->tv_usec + y->tv_usec;
60 while (result->tv_usec > 1000000)
62 result->tv_usec -= 1000000;
69 int timeval_add_time(struct timeval *result, int sec, int usec)
71 result->tv_sec += sec;
72 result->tv_usec += usec;
74 while (result->tv_usec > 1000000)
76 result->tv_usec -= 1000000;