| 1 | /* -*-c-*- |
| 2 | * |
| 3 | * $Id: tv.h,v 1.7 2004/04/08 01:36:13 mdw Exp $ |
| 4 | * |
| 5 | * Manipulation of timeval structures |
| 6 | * |
| 7 | * (c) 1998 Straylight/Edgeware |
| 8 | */ |
| 9 | |
| 10 | /*----- Licensing notice --------------------------------------------------* |
| 11 | * |
| 12 | * This file is part of the mLib utilities library. |
| 13 | * |
| 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. |
| 18 | * |
| 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. |
| 23 | * |
| 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, |
| 27 | * MA 02111-1307, USA. |
| 28 | */ |
| 29 | |
| 30 | #ifndef MLIB_TV_H |
| 31 | #define MLIB_TV_H |
| 32 | |
| 33 | #ifdef __cplusplus |
| 34 | extern "C" { |
| 35 | #endif |
| 36 | |
| 37 | /*----- Header files ------------------------------------------------------*/ |
| 38 | |
| 39 | #include <sys/time.h> |
| 40 | |
| 41 | /*----- A macro to make reading easier ------------------------------------*/ |
| 42 | |
| 43 | #define MILLION 1000000 |
| 44 | |
| 45 | /*----- Functions provided ------------------------------------------------*/ |
| 46 | |
| 47 | /* --- @tv_add@ --- * |
| 48 | * |
| 49 | * Arguments: @struct timeval *dst@ = destination block |
| 50 | * @const struct timeval *a, *b@ = source blocks |
| 51 | * |
| 52 | * Returns: --- |
| 53 | * |
| 54 | * Use: Adds two timevals. |
| 55 | */ |
| 56 | |
| 57 | extern void tv_add(struct timeval */*dst*/, |
| 58 | const struct timeval */*a*/, |
| 59 | const struct timeval */*b*/); |
| 60 | |
| 61 | #define TV_ADD(dst, a, b) TV_ADDL(dst, a, (b)->tv_sec, (b)->tv_usec) |
| 62 | |
| 63 | /* --- @tv_addl@ --- * |
| 64 | * |
| 65 | * Arguments: @struct timeval *dst@ = destination block |
| 66 | * @const struct timeval *a@ = source blocks |
| 67 | * @time_t sec@, @unsigned long usec@ = time to add |
| 68 | * |
| 69 | * Returns: --- |
| 70 | * |
| 71 | * Use: Adds a literal time in seconds and microseconds. |
| 72 | */ |
| 73 | |
| 74 | extern void tv_addl(struct timeval */*dst*/, |
| 75 | const struct timeval */*a*/, |
| 76 | time_t /*sec*/, unsigned long /*usec*/); |
| 77 | |
| 78 | #define TV_ADDL(dst, a, sec, usec) do { \ |
| 79 | (dst)->tv_sec = (a)->tv_sec + (sec); \ |
| 80 | (dst)->tv_usec = (a)->tv_usec + (usec); \ |
| 81 | if ((dst)->tv_usec >= MILLION) { \ |
| 82 | (dst)->tv_usec -= MILLION; \ |
| 83 | (dst)->tv_sec++; \ |
| 84 | } \ |
| 85 | } while (0) |
| 86 | |
| 87 | /* --- @tv_sub@ --- * |
| 88 | * |
| 89 | * Arguments: @struct timeval *dst@ = destination block |
| 90 | * @const struct timeval *a, *b@ = source blocks |
| 91 | * |
| 92 | * Returns: --- |
| 93 | * |
| 94 | * Use: Subtracts two timevals. |
| 95 | */ |
| 96 | |
| 97 | extern void tv_sub(struct timeval */*dst*/, |
| 98 | const struct timeval */*a*/, |
| 99 | const struct timeval */*b*/); |
| 100 | |
| 101 | #define TV_SUB(dst, a, b) TV_SUBL(dst, a, (b)->tv_sec, (b)->tv_usec) |
| 102 | |
| 103 | /* --- @tv_subl@ --- * |
| 104 | * |
| 105 | * Arguments: @struct timeval *dst@ = destination block |
| 106 | * @const struct timeval *a@ = source blocks |
| 107 | * @time_t sec@, @unsigned long usec@ = time to subtract |
| 108 | * |
| 109 | * Returns: --- |
| 110 | * |
| 111 | * Use: Subtracts a literal time in seconds and microseconds. |
| 112 | */ |
| 113 | |
| 114 | extern void tv_subl(struct timeval */*dst*/, |
| 115 | const struct timeval */*a*/, |
| 116 | time_t /*sec*/, unsigned long /*usec*/); |
| 117 | |
| 118 | #define TV_SUBL(dst, a, sec, usec) do { \ |
| 119 | (dst)->tv_sec = (a)->tv_sec - (sec); \ |
| 120 | if ((a)->tv_usec >= (usec)) \ |
| 121 | (dst)->tv_usec = (a)->tv_usec - (usec); \ |
| 122 | else { \ |
| 123 | (dst)->tv_usec = (a)->tv_usec + MILLION - (usec); \ |
| 124 | (dst)->tv_sec--; \ |
| 125 | } \ |
| 126 | } while (0) |
| 127 | |
| 128 | /* --- @tv_cmp@ --- * |
| 129 | * |
| 130 | * Arguments: @const struct timeval *a, *b@ = source blocks |
| 131 | * |
| 132 | * Returns: Less than, equal to, or greater than zero. |
| 133 | * |
| 134 | * Use: Compares two timevals. |
| 135 | */ |
| 136 | |
| 137 | extern int tv_cmp(const struct timeval */*a*/, |
| 138 | const struct timeval */*b*/); |
| 139 | |
| 140 | #define TV_CMP(a, op, b) ((a)->tv_sec == (b)->tv_sec ? \ |
| 141 | (a)->tv_usec op (b)->tv_usec : \ |
| 142 | (a)->tv_sec op (b)->tv_sec) |
| 143 | |
| 144 | /*----- That's all, folks -------------------------------------------------*/ |
| 145 | |
| 146 | #ifdef __cplusplus |
| 147 | } |
| 148 | #endif |
| 149 | |
| 150 | #endif |