cds/os/free_bsd/timer.h

   1 //$$CDS-header$$
   2
   3 #ifndef __CDS_OS_FREE_BSD_TIMER_H
   4 #define __CDS_OS_FREE_BSD_TIMER_H
   5
   6 #ifndef __CDS_OS_TIMER_H
   7 #   error "<cds/os/timer.h> must be included"
   8 #endif
   9
  10 #include <time.h>
  11 #include <sys/timespec.h>
  12
  13 //@cond none
  14 namespace cds { namespace OS {
  15
  16     CDS_CXX11_INLINE_NAMESPACE namespace Free_BSD {
  17
  18         // High resolution timer
  19         class Timer {
  20         public:
  21             typedef struct timespec native_timer_type;
  22             typedef long long       native_duration_type;
  23
  24         private:
  25             native_timer_type    m_tmStart;
  26
  27         public:
  28
  29             Timer() { current( m_tmStart ) ; }
  30
  31             static void current( native_timer_type& tmr )
  32             {
  33                 // faster than gettimeofday() and posix
  34 #           ifdef CLOCK_REALTIME_FAST
  35                 ::clock_gettime( CLOCK_REALTIME_FAST, &tmr );
  36 #           else
  37                 ::clock_gettime( CLOCK_REALTIME_FAST, &tmr );
  38 #           endif
  39             }
  40
  41             static native_timer_type    current()
  42             {
  43                 native_timer_type    tmr;
  44                 current(tmr);
  45                 return tmr;
  46             }
  47
  48             double reset()
  49             {
  50                 native_timer_type ts;
  51                 current( ts );
  52                 double dblRet = ( ts.tv_sec - m_tmStart.tv_sec ) + ( ts.tv_nsec - m_tmStart.tv_nsec ) / 1.0E9;
  53                 m_tmStart = ts;
  54                 return dblRet;
  55             }
  56
  57             double duration( native_duration_type dur )
  58             {
  59                 return double( dur ) / 1.0E9;
  60             }
  61
  62             double duration()
  63             {
  64                 return duration( native_duration() );
  65             }
  66
  67             native_duration_type    native_duration()
  68             {
  69                 native_timer_type ts;
  70                 current( ts );
  71                 return native_duration( m_tmStart, ts );
  72             }
  73
  74             static native_duration_type    native_duration( const native_timer_type& nStart, const native_timer_type& nEnd )
  75             {
  76                 return native_duration_type( nEnd.tv_sec - nStart.tv_sec ) * 1000000000 + ( nEnd.tv_nsec - nStart.tv_nsec);
  77             }
  78
  79             static unsigned long long random_seed()
  80             {
  81                 native_timer_type tmr;
  82                 current( tmr );
  83                 return ( ((unsigned long long)(tmr.tv_sec)) << 32 ) + tmr.tv_nsec;
  84             }
  85
  86         };
  87     }   // namespace Free_BSD
  88
  89 #ifndef CDS_CXX11_INLINE_NAMESPACE_SUPPORT
  90     typedef Free_BSD::Timer    Timer;
  91 #endif
  92
  93 }}   // namespace cds::OS
  94 //@endcond
  95
  96 #endif // #ifndef __CDS_OS_FREE_BSD_TIMER_H