1.1 --- a/src/timer/linux/SDL_systimer.c	Tue Oct 11 17:33:03 2005 +0000
     1.2 +++ b/src/timer/linux/SDL_systimer.c	Tue Oct 11 18:16:12 2005 +0000
     1.3 @@ -34,6 +34,16 @@
     1.4  #include <string.h>
     1.5  #include <errno.h>
     1.6  
     1.7 +/* The clock_gettime provides monotonous time, so we should use it if
     1.8 +   it's available. The clock_gettime function is behind ifdef
     1.9 +   for __USE_POSIX199309
    1.10 +   Tommi Kyntola (tommi.kyntola@ray.fi) 27/09/2005
    1.11 +*/
    1.12 +#if (defined _POSIX_TIMERS && _POSIX_TIMERS > 0)
    1.13 +#include <time.h>
    1.14 +#define USE_CLOCK_GETTIME
    1.15 +#endif
    1.16 +
    1.17  #include "SDL_error.h"
    1.18  #include "SDL_timer.h"
    1.19  #include "SDL_timer_c.h"
    1.20 @@ -86,6 +96,19 @@
    1.21  	float cpu_mhz;
    1.22  	unsigned long long tsc_start;
    1.23  	unsigned long long tsc_end;
    1.24 +/* Slight code doubling here for the sake of readability */
    1.25 +#ifdef USE_CLOCK_GETTIME
    1.26 +	struct timespec tv_start, tv_end;
    1.27 +	long usec_delay;
    1.28 +
    1.29 +	rdtsc(tsc_start);
    1.30 +	clock_gettime(CLOCK_MONOTONIC,&tv_start);
    1.31 +	sleep(1);
    1.32 +	rdtsc(tsc_end);
    1.33 +	clock_gettime(CLOCK_MONOTONIC,&tv_end);
    1.34 +	usec_delay = (1000000000L * (tv_end.tv_sec - tv_start.tv_sec) +
    1.35 +	                            (tv_end.tv_nsec - tv_start.tv_nsec)) / 1000;
    1.36 +#else
    1.37  	struct timeval tv_start, tv_end;
    1.38  	long usec_delay;
    1.39  
    1.40 @@ -96,6 +119,7 @@
    1.41  	gettimeofday(&tv_end, NULL);
    1.42  	usec_delay = 1000000L * (tv_end.tv_sec - tv_start.tv_sec) +
    1.43  	                        (tv_end.tv_usec - tv_start.tv_usec);
    1.44 +#endif /* USE_CLOCK_GETTIME */
    1.45  	cpu_mhz = (float)(tsc_end-tsc_start) / usec_delay;
    1.46  #if 0
    1.47  	printf("cpu MHz\t\t: %.3f\n", cpu_mhz);
    1.48 @@ -106,7 +130,11 @@
    1.49  #else
    1.50  
    1.51  /* The first ticks value of the application */
    1.52 +#ifdef USE_CLOCK_GETTIME
    1.53 +static struct timespec start;
    1.54 +#else
    1.55  static struct timeval start;
    1.56 +#endif /* USE_CLOCK_GETTIME */
    1.57  
    1.58  #endif  /* USE_RDTSC */
    1.59  
    1.60 @@ -119,9 +147,11 @@
    1.61  		cpu_mhz1000 = calc_cpu_mhz() * 1000.0f;
    1.62  	}
    1.63  	rdtsc(start);
    1.64 +#elif defined(USE_CLOCK_GETTIME)
    1.65 +	clock_gettime(CLOCK_MONOTONIC,&start);
    1.66  #else
    1.67  	gettimeofday(&start, NULL);
    1.68 -#endif /* USE_RDTSC */
    1.69 +#endif
    1.70  }
    1.71  
    1.72  Uint32 SDL_GetTicks (void)
    1.73 @@ -133,14 +163,19 @@
    1.74  	}
    1.75  	rdtsc(now);
    1.76  	return (Uint32)((now-start)/cpu_mhz1000);
    1.77 +#elif defined(USE_CLOCK_GETTIME)
    1.78 +	Uint32 ticks;
    1.79 +	struct timespec now;
    1.80 +	clock_gettime(CLOCK_MONOTONIC,&now);
    1.81 +	ticks=(now.tv_sec-start.tv_sec)*1000+(now.tv_nsec-start.tv_nsec)/1000000;
    1.82 +	return(ticks);
    1.83  #else
    1.84 +	Uint32 ticks;
    1.85  	struct timeval now;
    1.86 -	Uint32 ticks;
    1.87 -
    1.88  	gettimeofday(&now, NULL);
    1.89  	ticks=(now.tv_sec-start.tv_sec)*1000+(now.tv_usec-start.tv_usec)/1000;
    1.90  	return(ticks);
    1.91 -#endif /* USE_RDTSC */
    1.92 +#endif
    1.93  }
    1.94  
    1.95  void SDL_Delay (Uint32 ms)