osdep/timer-linux.c

   1 // Precise timer routines for LINUX  (C) LGB & A'rpi/ASTRAL
   2
   3 #include <unistd.h>
   4 #ifdef __BEOS__
   5 #define usleep(t) snooze(t)
   6 #endif
   7 #include <stdlib.h>
   8 #include <time.h>
   9 #include <sys/time.h>
  10 #include "config.h"
  11
  12 const char *timer_name =
  13 #ifdef HAVE_NANOSLEEP
  14   "nanosleep()";
  15 #else
  16   "usleep()";
  17 #endif
  18
  19 int usec_sleep(int usec_delay)
  20 {
  21 #ifdef HAVE_NANOSLEEP
  22     struct timespec ts;
  23     ts.tv_sec  =  usec_delay / 1000000;
  24     ts.tv_nsec = (usec_delay % 1000000) * 1000;
  25     return nanosleep(&ts, NULL);
  26 #else
  27     return usleep(usec_delay);
  28 #endif
  29 }
  30
  31 // Returns current time in microseconds
  32 unsigned int GetTimer(void){
  33   struct timeval tv;
  34 //  float s;
  35   gettimeofday(&tv,NULL);
  36 //  s=tv.tv_usec;s*=0.000001;s+=tv.tv_sec;
  37   return tv.tv_sec * 1000000 + tv.tv_usec;
  38 }
  39
  40 // Returns current time in milliseconds
  41 unsigned int GetTimerMS(void){
  42   struct timeval tv;
  43 //  float s;
  44   gettimeofday(&tv,NULL);
  45 //  s=tv.tv_usec;s*=0.000001;s+=tv.tv_sec;
  46   return tv.tv_sec * 1000 + tv.tv_usec / 1000;
  47 }
  48
  49 static unsigned int RelativeTime=0;
  50
  51 // Returns time spent between now and last call in seconds
  52 float GetRelativeTime(void){
  53 unsigned int t,r;
  54   t=GetTimer();
  55 //  t*=16;printf("time=%ud\n",t);
  56   r=t-RelativeTime;
  57   RelativeTime=t;
  58   return (float)r * 0.000001F;
  59 }
  60
  61 // Initialize timer, must be called at least once at start
  62 void InitTimer(void){
  63   GetRelativeTime();
  64 }
  65
  66
  67 #if 0
  68 #include <stdio.h>
  69 int main(void){
  70   float t=0;
  71   InitTimer();
  72   while(1){ t+=GetRelativeTime();printf("time= %10.6f\r",t);fflush(stdout); }
  73 }
  74 #endif
  75