gtimer.c

   1 /* GLIB - Library of useful routines for C programming
   2  * Copyright (C) 1995-1997  Peter Mattis, Spencer Kimball and Josh MacDonald
   3  *
   4  * This library is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU Library General Public
   6  * License as published by the Free Software Foundation; either
   7  * version 2 of the License, or (at your option) any later version.
   8  *
   9  * This library is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * Library General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Library General Public
  15  * License along with this library; if not, write to the
  16  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  17  * Boston, MA 02111-1307, USA.
  18  */
  19
  20 /*
  21  * MT safe
  22  */
  23
  24 #ifdef HAVE_CONFIG_H
  25 #include <config.h>
  26 #endif
  27
  28 #include "glib.h"
  29 #ifdef HAVE_UNISTD_H
  30 #include <unistd.h>
  31 #endif /* HAVE_UNISTD_H */
  32 #ifndef NATIVE_WIN32
  33 #include <sys/time.h>
  34 #endif /* NATIVE_WIN32 */
  35
  36 #ifdef NATIVE_WIN32
  37 #include <windows.h>
  38 #endif /* NATIVE_WIN32 */
  39
  40 typedef struct _GRealTimer GRealTimer;
  41
  42 struct _GRealTimer
  43 {
  44 #ifdef NATIVE_WIN32
  45   DWORD start;
  46   DWORD end;
  47 #else /* !NATIVE_WIN32 */
  48   struct timeval start;
  49   struct timeval end;
  50 #endif /* !NATIVE_WIN32 */
  51
  52   guint active : 1;
  53 };
  54
  55 GTimer*
  56 g_timer_new (void)
  57 {
  58   GRealTimer *timer;
  59
  60   timer = g_new (GRealTimer, 1);
  61   timer->active = TRUE;
  62
  63 #ifdef NATIVE_WIN32
  64   timer->start = GetTickCount ();
  65 #else /* !NATIVE_WIN32 */
  66   gettimeofday (&timer->start, NULL);
  67 #endif /* !NATIVE_WIN32 */
  68
  69   return ((GTimer*) timer);
  70 }
  71
  72 void
  73 g_timer_destroy (GTimer *timer)
  74 {
  75   g_assert (timer != NULL);
  76
  77   g_free (timer);
  78 }
  79
  80 void
  81 g_timer_start (GTimer *timer)
  82 {
  83   GRealTimer *rtimer;
  84
  85   g_assert (timer != NULL);
  86
  87   rtimer = (GRealTimer*) timer;
  88   rtimer->active = TRUE;
  89
  90 #ifdef NATIVE_WIN32
  91   rtimer->start = GetTickCount ();
  92 #else /* !NATIVE_WIN32 */
  93   gettimeofday (&rtimer->start, NULL);
  94 #endif /* !NATIVE_WIN32 */
  95 }
  96
  97 void
  98 g_timer_stop (GTimer *timer)
  99 {
 100   GRealTimer *rtimer;
 101
 102   g_assert (timer != NULL);
 103
 104   rtimer = (GRealTimer*) timer;
 105   rtimer->active = FALSE;
 106
 107 #ifdef NATIVE_WIN32
 108   rtimer->end = GetTickCount ();
 109 #else /* !NATIVE_WIN32 */
 110   gettimeofday (&rtimer->end, NULL);
 111 #endif /* !NATIVE_WIN32 */
 112 }
 113
 114 void
 115 g_timer_reset (GTimer *timer)
 116 {
 117   GRealTimer *rtimer;
 118
 119   g_assert (timer != NULL);
 120
 121   rtimer = (GRealTimer*) timer;
 122
 123 #ifdef NATIVE_WIN32
 124    rtimer->start = GetTickCount ();
 125 #else /* !NATIVE_WIN32 */
 126   gettimeofday (&rtimer->start, NULL);
 127 #endif /* !NATIVE_WIN32 */
 128 }
 129
 130 gdouble
 131 g_timer_elapsed (GTimer *timer,
 132                  gulong *microseconds)
 133 {
 134   GRealTimer *rtimer;
 135   gdouble total;
 136 #ifndef NATIVE_WIN32
 137   struct timeval elapsed;
 138 #endif /* NATIVE_WIN32 */
 139
 140   g_return_val_if_fail (timer != NULL, 0);
 141
 142   rtimer = (GRealTimer*) timer;
 143
 144 #ifdef NATIVE_WIN32
 145   if (rtimer->active)
 146     rtimer->end = GetTickCount ();
 147
 148   /* Check for wraparound, which happens every 49.7 days.
 149    * No, Win95 machines probably are never running for that long,
 150    * but NT machines are.
 151    */
 152   if (rtimer->end < rtimer->start)
 153     total = (UINT_MAX - (rtimer->start - rtimer->end)) / 1000.0;
 154   else
 155     total = (rtimer->end - rtimer->start) / 1000.0;
 156
 157   if (microseconds)
 158     {
 159       if (rtimer->end < rtimer->start)
 160         *microseconds =
 161           ((UINT_MAX - (rtimer->start - rtimer->end)) % 1000) * 1000;
 162       else
 163         *microseconds =
 164           ((rtimer->end - rtimer->start) % 1000) * 1000;
 165     }
 166 #else /* !NATIVE_WIN32 */
 167   if (rtimer->active)
 168     gettimeofday (&rtimer->end, NULL);
 169
 170   if (rtimer->start.tv_usec > rtimer->end.tv_usec)
 171     {
 172       rtimer->end.tv_usec += 1000000;
 173       rtimer->end.tv_sec--;
 174     }
 175
 176   elapsed.tv_usec = rtimer->end.tv_usec - rtimer->start.tv_usec;
 177   elapsed.tv_sec = rtimer->end.tv_sec - rtimer->start.tv_sec;
 178
 179   total = elapsed.tv_sec + ((gdouble) elapsed.tv_usec / 1e6);
 180
 181   if (microseconds)
 182     *microseconds = elapsed.tv_usec;
 183 #endif /* !NATIVE_WIN32 */
 184
 185   return total;
 186 }