traefik/vendor/gopkg.in/DataDog/dd-trace-go.v1/ddtrace/tracer/time_windows.go

36 lines
889 B
Go
Raw Normal View History

package tracer
import (
"time"
"golang.org/x/sys/windows"
2019-07-18 19:36:05 +00:00
"gopkg.in/DataDog/dd-trace-go.v1/internal/log"
)
// This method is more precise than the go1.8 time.Now on Windows
// See https://msdn.microsoft.com/en-us/library/windows/desktop/hh706895(v=vs.85).aspx
// It is however ~10x slower and requires Windows 8+.
func highPrecisionNow() int64 {
var ft windows.Filetime
windows.GetSystemTimePreciseAsFileTime(&ft)
return ft.Nanoseconds()
}
func lowPrecisionNow() int64 {
return time.Now().UTC().UnixNano()
}
var now func() int64
// If GetSystemTimePreciseAsFileTime is not available we default to the less
// precise implementation based on time.Now()
func init() {
if err := windows.LoadGetSystemTimePreciseAsFileTime(); err != nil {
2019-07-18 19:36:05 +00:00
log.Warn("Unable to load high precison timer, defaulting to time.Now()")
now = lowPrecisionNow
} else {
now = highPrecisionNow
}
}