mono/eglib/gtimer-win32.c

   1 /*
   2  * Timer
   3  *
   4  * Author:
   5  *   Gonzalo Paniagua Javier (gonzalo@novell.com
   6  *
   7  * (C) 2006 Novell, Inc.
   8  *
   9  * Permission is hereby granted, free of charge, to any person obtaining
  10  * a copy of this software and associated documentation files (the
  11  * "Software"), to deal in the Software without restriction, including
  12  * without limitation the rights to use, copy, modify, merge, publish,
  13  * distribute, sublicense, and/or sell copies of the Software, and to
  14  * permit persons to whom the Software is furnished to do so, subject to
  15  * the following conditions:
  16  *
  17  * The above copyright notice and this permission notice shall be
  18  * included in all copies or substantial portions of the Software.
  19  *
  20  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  21  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  22  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  23  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  24  * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  25  * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  26  * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  27  */
  28 #include "config.h"
  29 #include <glib.h>
  30 #include <windows.h>
  31
  32 struct _GTimer {
  33         guint64 start;
  34         guint64 stop;
  35 };
  36
  37 GTimer *g_timer_new (void)
  38 {
  39         GTimer *timer;
  40
  41         timer = g_new0 (GTimer, 1);
  42         g_timer_start (timer);
  43         return timer;
  44 }
  45
  46 void
  47 g_timer_destroy (GTimer *timer)
  48 {
  49         g_return_if_fail (timer != NULL);
  50         g_free (timer);
  51 }
  52
  53 void
  54 g_timer_start (GTimer *timer)
  55 {
  56         g_return_if_fail (timer != NULL);
  57
  58         QueryPerformanceCounter ((LARGE_INTEGER*)&timer->start);
  59 }
  60
  61 void
  62 g_timer_stop (GTimer *timer)
  63 {
  64         g_return_if_fail (timer != NULL);
  65
  66         QueryPerformanceCounter ((LARGE_INTEGER*)&timer->stop);
  67 }
  68
  69 gdouble
  70 g_timer_elapsed (GTimer *timer, gulong *microseconds)
  71 {
  72         static guint64 freq = 0;
  73         guint64 delta, stop;
  74
  75         if (freq == 0) {
  76                 if (!QueryPerformanceFrequency ((LARGE_INTEGER *)&freq))
  77                         freq = 1;
  78         }
  79
  80         if (timer->stop == 0) {
  81                 QueryPerformanceCounter ((LARGE_INTEGER*)&stop);
  82         }
  83         else {
  84                 stop = timer->stop;
  85         }
  86
  87         delta = stop - timer->start;
  88
  89         if (microseconds)
  90                 *microseconds = (gulong) (delta * (1000000.0 / freq));
  91
  92         return (gdouble) delta / (gdouble) freq;
  93 }
  94
  95