improved windows Get() performance (x100) by not returning ChangeTime

in order to obtain the ChangeTime is was necessary to open the file, however Get() should only inspect the contents of the passed os.FileInfo. Stat() on the other hand does still open the file and can still obtain ChangeTime.

ctime_windows.go

@@ -29,13 +29,13 @@ func StatFile(file *os.File) (Timespec, error) {
 	return t, nil
 }
 
-func statEx(file string) (Timespec, error) {
+func Stat(name string) (Timespec, error) {
 	if findProcErr != nil {
 		// fail fast, don't bother opening the file
 		return nil, findProcErr
 	}
 
-	f, err := os.Open(file)
+	f, err := os.Open(name)
 	if err != nil {
 		return nil, err
 	}

stat_generic.go

@@ -0,0 +1,13 @@
+// +build !windows
+
+package times
+
+import "os"
+
+func Stat(name string) (Timespec, error) {
+	fi, err := os.Stat(name)
+	if err != nil {
+		return nil, err
+	}
+	return getTimespec(fi), nil
+}

stat.go → times.go

@@ -11,15 +11,6 @@ func Get(fi os.FileInfo) Timespec {
 	return getTimespec(fi)
 }
 
-// Stat returns the Timespec for the given filename
-func Stat(name string) (Timespec, error) {
-	fi, err := os.Stat(name)
-	if err != nil {
-		return nil, err
-	}
-	return getTimespec(fi), nil
-}
-
 // Timespec provides access to file times.
 // ChangeTime() panics unless HasChangeTime() is true and
 // BirthTime() panics unless HasBirthTime() is true.

times_windows.go

@@ -27,10 +27,6 @@ type timespec struct {
 }
 
 func getTimespec(fi os.FileInfo) Timespec {
-	if ts, err := statEx(fi.Name()); err == nil {
-		return ts
-	}
-
 	var t timespec
 	stat := fi.Sys().(*syscall.Win32FileAttributeData)
 	t.atime.v = time.Unix(0, stat.LastAccessTime.Nanoseconds())