mdw@git.distorted.org.uk Git - disorder/blob - lib/timeval.h

   1 /*
   2  * This file is part of DisOrder.
   3  * Copyright (C) 2007-2009 Richard Kettlewell
   4  *
   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 3 of the License, or
   8  * (at your option) any later version.
   9  *
  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.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  17  */
  18 /** @file lib/timeval.h
  19  * @brief Arithmetic on timeval structures
  20  */
  21 #ifndef TIMEVAL_H
  22 #define TIMEVAL_H
  23
  24 #include <time.h>
  25 #include <sys/time.h>
  26
  27 static inline struct timeval tvsub(const struct timeval a,
  28                                    const struct timeval b) {
  29   struct timeval r;
  30
  31   r.tv_sec = a.tv_sec - b.tv_sec;
  32   r.tv_usec = a.tv_usec - b.tv_usec;
  33   if(r.tv_usec < 0) {
  34     r.tv_usec += 1000000;
  35     r.tv_sec--;
  36   }
  37   if(r.tv_usec > 999999) {
  38     r.tv_usec -= 1000000;
  39     r.tv_sec++;
  40   }
  41   return r;
  42 }
  43
  44 static inline struct timeval tvadd(const struct timeval a,
  45                                    const struct timeval b) {
  46   struct timeval r;
  47
  48   r.tv_sec = a.tv_sec + b.tv_sec;
  49   r.tv_usec = a.tv_usec + b.tv_usec;
  50   if(r.tv_usec < 0) {
  51     r.tv_usec += 1000000;
  52     r.tv_sec--;
  53   }
  54   if(r.tv_usec > 999999) {
  55     r.tv_usec -= 1000000;
  56     r.tv_sec++;
  57   }
  58   return r;
  59 }
  60
  61 static inline double tvdouble(const struct timeval a) {
  62   return a.tv_sec + a.tv_usec / 1000000.0;
  63 }
  64
  65 static inline int64_t tvsub_us(const struct timeval a,
  66                                const struct timeval b) {
  67   return (((uint64_t)a.tv_sec * 1000000 + a.tv_usec)
  68           - ((uint64_t)b.tv_sec * 1000000 + b.tv_usec));
  69 }
  70
  71 /** @brief Great-than comparison for timevals */
  72 static inline int tvgt(const struct timeval *a, const struct timeval *b) {
  73   if(a->tv_sec > b->tv_sec)
  74     return 1;
  75   if(a->tv_sec == b->tv_sec
  76      && a->tv_usec > b->tv_usec)
  77     return 1;
  78   return 0;
  79 }
  80
  81 /** @brief Less-than
  82     comparison for timevals */
  83 static inline int tvlt(const struct timeval *a, const struct timeval *b) {
  84   if(a->tv_sec < b->tv_sec)
  85     return 1;
  86   if(a->tv_sec == b->tv_sec
  87      && a->tv_usec < b->tv_usec)
  88     return 1;
  89   return 0;
  90 }
  91
  92 /** @brief Greater-than-or-equal comparison for timevals */
  93 static inline int tvge(const struct timeval *a, const struct timeval *b) {
  94   return !tvlt(a, b);
  95 }
  96
  97 /** @brief Less-than-or-equal comparison for timevals */
  98 static inline int tvle(const struct timeval *a, const struct timeval *b) {
  99   return !tvgt(a, b);
 100 }
 101
 102 #endif /* TIMEVAL_H */
 103
 104 /*
 105 Local Variables:
 106 c-basic-offset:2
 107 comment-column:40
 108 fill-column:79
 109 indent-tabs-mode:nil
 110 End:
 111 */