src/OS/Clock.cpp

   1 /*
   2 Copyright_License {
   3
   4   XCSoar Glide Computer - http://www.xcsoar.org/
   5   Copyright (C) 2000-2013 The XCSoar Project
   6   A detailed list of copyright holders can be found in the file "AUTHORS".
   7
   8   This program is free software; you can redistribute it and/or
   9   modify it under the terms of the GNU General Public License
  10   as published by the Free Software Foundation; either version 2
  11   of the License, or (at your option) any later version.
  12
  13   This program is distributed in the hope that it will be useful,
  14   but WITHOUT ANY WARRANTY; without even the implied warranty of
  15   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16   GNU General Public License for more details.
  17
  18   You should have received a copy of the GNU General Public License
  19   along with this program; if not, write to the Free Software
  20   Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  21 }
  22 */
  23
  24 #include "OS/Clock.hpp"
  25
  26 #if defined(__APPLE__)
  27 #include <mach/mach_time.h>
  28 #elif defined(HAVE_POSIX) && !defined(__CYGWIN__)
  29 #include <time.h>
  30 #ifndef __GLIBC__
  31 #include <sys/time.h>
  32 #endif
  33 #else /* !HAVE_POSIX */
  34 #include <windows.h>
  35 #endif /* !HAVE_POSIX */
  36
  37 unsigned
  38 MonotonicClockMS()
  39 {
  40 #if defined(HAVE_POSIX) && !defined(__CYGWIN__)
  41 #ifdef CLOCK_MONOTONIC
  42   struct timespec ts;
  43   clock_gettime(CLOCK_MONOTONIC, &ts);
  44   return ts.tv_sec * 1000 + ts.tv_nsec / 1000000;
  45 #elif defined(__APPLE__) /* OS X does not define CLOCK_MONOTONIC */
  46   static mach_timebase_info_data_t base;
  47   if (base.denom == 0)
  48     (void)mach_timebase_info(&base);
  49
  50   return (unsigned)((mach_absolute_time() * base.numer)
  51                     / (1000000 * base.denom));
  52 #else
  53   /* we have no monotonic clock, fall back to gettimeofday() */
  54   struct timeval tv;
  55   gettimeofday(&tv, 0);
  56   return tv.tv_sec * 1000 + tv.tv_usec / 1000;
  57 #endif
  58 #else /* !HAVE_POSIX */
  59   return ::GetTickCount();
  60 #endif /* !HAVE_POSIX */
  61 }
  62
  63 uint64_t
  64 MonotonicClockUS()
  65 {
  66 #if defined(HAVE_POSIX) && !defined(__CYGWIN__)
  67 #ifdef CLOCK_MONOTONIC
  68   struct timespec ts;
  69   clock_gettime(CLOCK_MONOTONIC, &ts);
  70   return uint64_t(ts.tv_sec) * 1000000 + uint64_t(ts.tv_nsec) / 1000;
  71 #elif defined(__APPLE__) /* OS X does not define CLOCK_MONOTONIC */
  72   static mach_timebase_info_data_t base;
  73   if (base.denom == 0)
  74     (void)mach_timebase_info(&base);
  75
  76   return (uint64_t(mach_absolute_time()) * uint64_t(base.numer))
  77     / (1000 * uint64_t(base.denom));
  78 #else
  79   /* we have no monotonic clock, fall back to gettimeofday() */
  80   struct timeval tv;
  81   gettimeofday(&tv, 0);
  82   return uint64_t(tv.tv_sec) * 1000 + uint64_t(tv.tv_usec) / 1000;
  83 #endif
  84 #else /* !HAVE_POSIX */
  85   LARGE_INTEGER l_value, l_frequency;
  86
  87   if (!::QueryPerformanceCounter(&l_value) ||
  88       !::QueryPerformanceFrequency(&l_frequency))
  89     return 0;
  90
  91   uint64_t value = l_value.QuadPart;
  92   uint64_t frequency = l_frequency.QuadPart;
  93
  94   if (frequency > 1000000) {
  95     value *= 10000;
  96     value /= frequency / 100;
  97   } else if (frequency < 1000000) {
  98     value *= 10000;
  99     value /= frequency;
 100     value *= 100;
 101   }
 102
 103   return value;
 104 #endif /* !HAVE_POSIX */
 105 }
 106
 107 int
 108 GetSystemUTCOffset()
 109 {
 110 #ifdef HAVE_POSIX
 111   // XXX implement
 112   return 0;
 113 #else
 114   TIME_ZONE_INFORMATION TimeZoneInformation;
 115   DWORD tzi = GetTimeZoneInformation(&TimeZoneInformation);
 116
 117   int offset = -TimeZoneInformation.Bias * 60;
 118   if (tzi == TIME_ZONE_ID_STANDARD)
 119     offset -= TimeZoneInformation.StandardBias * 60;
 120
 121   if (tzi == TIME_ZONE_ID_DAYLIGHT)
 122     offset -= TimeZoneInformation.DaylightBias * 60;
 123
 124   return offset;
 125 #endif
 126 }