ltt/branches/poly/ltt/time.h

   1 /* This file is part of the Linux Trace Toolkit trace reading library
   2  * Copyright (C) 2003-2004 Michel Dagenais
   3  *
   4  * This library is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU Lesser General Public
   6  * License Version 2.1 as published by the Free Software Foundation.
   7  *
   8  * This library is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  11  * Lesser General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU Lesser General Public
  14  * License along with this library; if not, write to the
  15  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  16  * Boston, MA 02111-1307, USA.
  17  */
  18
  19 #ifndef LTT_TIME_H
  20 #define LTT_TIME_H
  21
  22
  23 typedef struct _LttTime {
  24   unsigned long tv_sec;
  25   unsigned long tv_nsec;
  26 } LttTime;
  27
  28
  29 static const unsigned long NANOSECONDS_PER_SECOND = 1000000000;
  30
  31 static const LttTime ltt_time_zero = { 0, 0};
  32
  33
  34 static inline LttTime ltt_time_sub(LttTime t1, LttTime t2)
  35 {
  36   LttTime res;
  37   res.tv_sec  = t1.tv_sec  - t2.tv_sec;
  38   if(t1.tv_nsec < t2.tv_nsec) {
  39     res.tv_sec--;
  40     res.tv_nsec = NANOSECONDS_PER_SECOND + t1.tv_nsec - t2.tv_nsec;
  41   }
  42   else {
  43     res.tv_nsec = t1.tv_nsec - t2.tv_nsec;
  44   }
  45   return res;
  46 }
  47
  48
  49 static inline LttTime ltt_time_add(LttTime t1, LttTime t2)
  50 {
  51   LttTime res;
  52   res.tv_sec  = t1.tv_sec  + t2.tv_sec;
  53   res.tv_nsec = t1.tv_nsec + t2.tv_nsec;
  54   if(res.tv_nsec >= NANOSECONDS_PER_SECOND) {
  55     res.tv_sec++;
  56     res.tv_nsec -= NANOSECONDS_PER_SECOND;
  57   }
  58   return res;
  59 }
  60
  61
  62 static inline LttTime ltt_time_mul(LttTime t1, float f)
  63 {
  64   LttTime res;
  65   float d;
  66   double sec;
  67
  68   if(f == 0.0){
  69     res.tv_sec = 0;
  70     res.tv_nsec = 0;
  71   }else{
  72     d = 1.0/f;
  73     sec = t1.tv_sec / (double)d;
  74     res.tv_sec = sec;
  75     res.tv_nsec = t1.tv_nsec / (double)d + (sec - res.tv_sec) *
  76                   NANOSECONDS_PER_SECOND;
  77     res.tv_sec += res.tv_nsec / NANOSECONDS_PER_SECOND;
  78     res.tv_nsec %= NANOSECONDS_PER_SECOND;
  79   }
  80   return res;
  81 }
  82
  83
  84 static inline LttTime ltt_time_div(LttTime t1, float f)
  85 {
  86   double sec;
  87   LttTime res;
  88
  89   sec = t1.tv_sec / (double)f;
  90   res.tv_sec = sec;
  91   res.tv_nsec = t1.tv_nsec / (double)f + (sec - res.tv_sec) *
  92       NANOSECONDS_PER_SECOND;
  93   res.tv_sec += res.tv_nsec / NANOSECONDS_PER_SECOND;
  94   res.tv_nsec %= NANOSECONDS_PER_SECOND;
  95   return res;
  96 }
  97
  98
  99 static inline int ltt_time_compare(LttTime t1, LttTime t2)
 100 {
 101   if(t1.tv_sec > t2.tv_sec) return 1;
 102   if(t1.tv_sec < t2.tv_sec) return -1;
 103   if(t1.tv_nsec > t2.tv_nsec) return 1;
 104   if(t1.tv_nsec < t2.tv_nsec) return -1;
 105   return 0;
 106 }
 107
 108
 109 static inline double ltt_time_to_double(LttTime t1)
 110 {
 111   return (double)t1.tv_sec + (double)t1.tv_nsec / NANOSECONDS_PER_SECOND;
 112 }
 113
 114
 115 static inline LttTime ltt_time_from_double(double t1)
 116 {
 117   LttTime res;
 118   res.tv_sec = t1;
 119   res.tv_nsec = (t1 - res.tv_sec) * NANOSECONDS_PER_SECOND;
 120   return res;
 121 }
 122
 123 #endif // LTT_TIME_H