src/common/stopwatch.cpp

   1 ///////////////////////////////////////////////////////////////////////////////
   2 // Name:        src/common/stopwatch.cpp
   3 // Purpose:     wxStopWatch and other non-GUI stuff from wx/timer.h
   4 // Author:
   5 //    Original version by Julian Smart
   6 //    Vadim Zeitlin got rid of all ifdefs (11.12.99)
   7 //    Sylvain Bougnoux added wxStopWatch class
   8 //    Guillermo Rodriguez <guille@iies.es> rewrote from scratch (Dic/99)
   9 // Modified by:
  10 // Created:     20.06.2003 (extracted from common/timercmn.cpp)
  11 // RCS-ID:      $Id$
  12 // Copyright:   (c) 1998-2003 wxWidgets Team
  13 // Licence:     wxWindows licence
  14 ///////////////////////////////////////////////////////////////////////////////
  15
  16 // ============================================================================
  17 // declarations
  18 // ============================================================================
  19
  20 // ----------------------------------------------------------------------------
  21 // headers
  22 // ----------------------------------------------------------------------------
  23
  24 // for compilers that support precompilation, includes "wx.h".
  25 #include "wx/wxprec.h"
  26
  27 #ifdef __BORLANDC__
  28     #pragma hdrstop
  29 #endif
  30
  31 #include "wx/stopwatch.h"
  32
  33 #if wxUSE_STOPWATCH
  34
  35 #ifndef WX_PRECOMP
  36     #ifdef __WXMSW__
  37         #include "wx/msw/wrapwin.h"
  38     #endif
  39     #include "wx/log.h"
  40 #endif //WX_PRECOMP
  41
  42 // ============================================================================
  43 // implementation
  44 // ============================================================================
  45
  46 // ----------------------------------------------------------------------------
  47 // wxStopWatch
  48 // ----------------------------------------------------------------------------
  49
  50 namespace
  51 {
  52
  53 #ifdef __WXMSW__
  54
  55 struct PerfCounter
  56 {
  57     PerfCounter()
  58     {
  59         init = false;
  60     }
  61
  62     bool CanBeUsed() const
  63     {
  64         return freq.QuadPart != 0;
  65     }
  66
  67     wxCriticalSection cs;
  68     LARGE_INTEGER freq;
  69     bool init;
  70 } gs_perfCounter;
  71
  72 #endif // __WXMSW__
  73
  74 const int MILLISECONDS_PER_SECOND = 1000;
  75 const int MICROSECONDS_PER_MILLISECOND = 1000;
  76 const int MICROSECONDS_PER_SECOND = 1000*1000;
  77
  78 } // anonymous namespace
  79
  80 void wxStopWatch::DoStart()
  81 {
  82 #ifdef __WXMSW__
  83     if ( !gs_perfCounter.init )
  84     {
  85         wxCriticalSectionLocker lock(gs_perfCounter.cs);
  86         ::QueryPerformanceFrequency(&gs_perfCounter.freq);
  87
  88         // Just a sanity check: it's not supposed to happen but verify that
  89         // ::QueryPerformanceCounter() succeeds so that we can really use it.
  90         LARGE_INTEGER counter;
  91         if ( !::QueryPerformanceCounter(&counter) )
  92         {
  93             wxLogDebug("QueryPerformanceCounter() unexpected failed (%s), "
  94                        "will not use it.", wxSysErrorMsg());
  95
  96             gs_perfCounter.freq.QuadPart = 0;
  97         }
  98
  99         gs_perfCounter.init = true;
 100     }
 101 #endif // __WXMSW__
 102
 103     m_t0 = GetCurrentClockValue();
 104 }
 105
 106 wxLongLong wxStopWatch::GetClockFreq() const
 107 {
 108 #ifdef __WXMSW__
 109     // Under MSW we use the high resolution performance counter timer which has
 110     // its own frequency (usually related to the CPU clock speed).
 111     if ( gs_perfCounter.CanBeUsed() )
 112         return gs_perfCounter.freq.QuadPart;
 113 #endif // __WXMSW__
 114
 115 #ifdef HAVE_GETTIMEOFDAY
 116     // With gettimeofday() we can have nominally microsecond precision and
 117     // while this is not the case in practice, it's still better than
 118     // millisecond.
 119     return MICROSECONDS_PER_SECOND;
 120 #else // !HAVE_GETTIMEOFDAY
 121     // Currently milliseconds are used everywhere else.
 122     return MILLISECONDS_PER_SECOND;
 123 #endif // HAVE_GETTIMEOFDAY/!HAVE_GETTIMEOFDAY
 124 }
 125
 126 void wxStopWatch::Start(long t0)
 127 {
 128     DoStart();
 129
 130     m_t0 -= (wxLongLong(t0)*GetClockFreq())/MILLISECONDS_PER_SECOND;
 131 }
 132
 133 wxLongLong wxStopWatch::GetCurrentClockValue() const
 134 {
 135 #ifdef __WXMSW__
 136     if ( gs_perfCounter.CanBeUsed() )
 137     {
 138         LARGE_INTEGER counter;
 139         ::QueryPerformanceCounter(&counter);
 140         return counter.QuadPart;
 141     }
 142 #endif // __WXMSW__
 143
 144 #ifdef HAVE_GETTIMEOFDAY
 145     return wxGetUTCTimeUSec();
 146 #else // !HAVE_GETTIMEOFDAY
 147     return wxGetUTCTimeMillis();
 148 #endif // HAVE_GETTIMEOFDAY/!HAVE_GETTIMEOFDAY
 149 }
 150
 151 wxLongLong wxStopWatch::TimeInMicro() const
 152 {
 153     const wxLongLong elapsed(m_pauseCount ? m_elapsedBeforePause
 154                                           : GetCurrentClockValue() - m_t0);
 155
 156     return (elapsed*MICROSECONDS_PER_SECOND)/GetClockFreq();
 157 }
 158
 159 #endif // wxUSE_STOPWATCH
 160
 161 // ----------------------------------------------------------------------------
 162 // old timer functions superceded by wxStopWatch
 163 // ----------------------------------------------------------------------------
 164
 165 #if wxUSE_LONGLONG
 166
 167 static wxLongLong wxStartTime = 0l;
 168
 169 // starts the global timer
 170 void wxStartTimer()
 171 {
 172     wxStartTime = wxGetUTCTimeMillis();
 173 }
 174
 175 // Returns elapsed time in milliseconds
 176 long wxGetElapsedTime(bool resetTimer)
 177 {
 178     wxLongLong oldTime = wxStartTime;
 179     wxLongLong newTime = wxGetUTCTimeMillis();
 180
 181     if ( resetTimer )
 182         wxStartTime = newTime;
 183
 184     return (newTime - oldTime).GetLo();
 185 }
 186
 187 #endif // wxUSE_LONGLONG