3 * $Id: tv.c,v 1.4 1999/05/17 20:37:52 mdw Exp $
5 * Manipulation of timeval structures
7 * (c) 1998 Straylight/Edgeware
10 /*----- Licensing notice --------------------------------------------------*
12 * This file is part of the mLib utilities library.
14 * mLib is free software; you can redistribute it and/or modify
15 * it under the terms of the GNU Library General Public License as
16 * published by the Free Software Foundation; either version 2 of the
17 * License, or (at your option) any later version.
19 * mLib is distributed in the hope that it will be useful,
20 * but WITHOUT ANY WARRANTY; without even the implied warranty of
21 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
22 * GNU Library General Public License for more details.
24 * You should have received a copy of the GNU Library General Public
25 * License along with mLib; if not, write to the Free
26 * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
30 /*----- Revision history --------------------------------------------------*
33 * Revision 1.4 1999/05/17 20:37:52 mdw
34 * New function `tv_addl' to add a literal to a time value. Use magical
35 * `MILLION' constant in place of 1000000 for ease of reading.
37 * Revision 1.3 1999/05/06 19:51:36 mdw
38 * Reformatted the LGPL notice a little bit.
40 * Revision 1.2 1999/05/05 18:50:31 mdw
41 * Change licensing conditions to LGPL.
43 * Revision 1.1 1998/11/25 23:30:01 mdw
48 /*----- Header files ------------------------------------------------------*/
53 /*----- A macro to make reading easier ------------------------------------*/
55 #define MILLION 1000000
57 /*----- Main code ---------------------------------------------------------*/
61 * Arguments: @struct timeval *dst@ = destination block
62 * @const struct timeval *a, *b@ = source blocks
66 * Use: Adds two timevals.
69 void tv_add(struct timeval *dst,
70 const struct timeval *a, const struct timeval *b)
72 dst->tv_sec = a->tv_sec + b->tv_sec;
73 dst->tv_usec = a->tv_usec + b->tv_usec;
74 if (dst->tv_usec >= MILLION) {
75 dst->tv_usec -= MILLION;
80 /* --- @tv_addl@ --- *
82 * Arguments: @struct timeval *dst@ = destination block
83 * @const struct timeval *a@ = source blocks
84 * @time_t sec@, @unsigned long usec@ = time to add
88 * Use: Adds a literal time in seconds and microseconds.
91 void tv_addl(struct timeval *dst, const struct timeval *a,
92 time_t sec, unsigned long usec)
94 dst->tv_sec = a->tv_sec + sec;
95 dst->tv_usec = a->tv_usec + usec;
96 if (dst->tv_usec >= MILLION) {
97 dst->tv_usec -= MILLION;
102 /* --- @tv_sub@ --- *
104 * Arguments: @struct timeval *dst@ = destination block
105 * @const struct timeval *a, *b@ = source blocks
109 * Use: Subtracts two timevals.
112 void tv_sub(struct timeval *dst,
113 const struct timeval *a, const struct timeval *b)
115 dst->tv_sec = a->tv_sec - b->tv_sec;
116 if (a->tv_usec >= b->tv_usec)
117 dst->tv_usec = a->tv_usec - b->tv_usec;
119 dst->tv_usec = a->tv_usec + MILLION - b->tv_usec;
124 /* --- @tv_cmp@ --- *
126 * Arguments: @const struct timeval *a, *b@ = source blocks
128 * Returns: Less than, equal to, or greater than zero.
130 * Use: Compares two timevals.
133 int tv_cmp(const struct timeval *a, const struct timeval *b)
135 if (a->tv_sec > b->tv_sec)
137 else if (a->tv_sec < b->tv_sec)
139 else if (a->tv_usec > b->tv_usec)
141 else if (a->tv_usec < b->tv_usec)
147 /*----- That's all, folks -------------------------------------------------*/