Use wxGetUTCTimeUSec() in wxStopWatch under Unix for higher precision.

If gettimeofday() is available we can achieve better than millisecond
precision (even if it usually isn't as high as microsecond), so use it as
clock source in wxStopWatch.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@69841 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

diff --git a/docs/changes.txt b/docs/changes.txt
index 68cf93d967e0d54eba5adaf8f5f3109d89ee8d78..fc1a6a4837d6df682d773f4591370e1fd95c7ead 100644 (file)
--- a/docs/changes.txt
+++ b/docs/changes.txt
@@ -459,7 +459,8 @@ All:
 - Fix crash in wxArray::insert() overload taking iterator range (wsu).
 - Added wxEventFilter class and wxEvtHandler::{Add,Remove}Filter().
 - Added convenient wxCmdLineParser::AddLong{Option,Switch}() wrappers.
-- Added wxStopWatch::TimeInMicro() and wxGetUTCTimeUSec().
+- Added wxStopWatch::TimeInMicro() and wxGetUTCTimeUSec() and improved
+  wxStopWatch precision.
 - Made wxGetLocalTimeMillis() really return local time, added
   wxGetUTCTimeMillis() returning what this function used to return.
 

diff --git a/src/common/stopwatch.cpp b/src/common/stopwatch.cpp
index b0e6ddde4085cdb0fec25f6363485044e9735baf..f077378b3abaf5762e031d960d58e4a75a3000a3 100644 (file)
--- a/src/common/stopwatch.cpp
+++ b/src/common/stopwatch.cpp
@@ -112,8 +112,15 @@ wxLongLong wxStopWatch::GetClockFreq() const
         return gs_perfCounter.freq.QuadPart;
 #endif // __WXMSW__
 
+#ifdef HAVE_GETTIMEOFDAY
+    // With gettimeofday() we can have nominally microsecond precision and
+    // while this is not the case in practice, it's still better than
+    // millisecond.
+    return MICROSECONDS_PER_SECOND;
+#else // !HAVE_GETTIMEOFDAY
     // Currently milliseconds are used everywhere else.
     return MILLISECONDS_PER_SECOND;
+#endif // HAVE_GETTIMEOFDAY/!HAVE_GETTIMEOFDAY
 }
 
 void wxStopWatch::Start(long t0)
@@ -134,7 +141,11 @@ wxLongLong wxStopWatch::GetCurrentClockValue() const
     }
 #endif // __WXMSW__
 
+#ifdef HAVE_GETTIMEOFDAY
+    return wxGetUTCTimeUSec();
+#else // !HAVE_GETTIMEOFDAY
     return wxGetUTCTimeMillis();
+#endif // HAVE_GETTIMEOFDAY/!HAVE_GETTIMEOFDAY
 }
 
 wxLongLong wxStopWatch::TimeInMicro() const