os, syscall: permit setting mtime to Unix 0 on Windows

This edge case was accidentally broken by CL 219638.

Change-Id: I673b3b580fbe379a04f8650cf5969fe9bce83691
Reviewed-on: https://go-review.googlesource.com/c/go/+/495036
Reviewed-by: Cherry Mui <cherryyz@google.com>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@google.com>
Run-TryBot: Ian Lance Taylor <iant@google.com>
Auto-Submit: Ian Lance Taylor <iant@google.com>

diff --git a/src/os/file_windows.go b/src/os/file_windows.go
index 37db3f931c69c04a2934f70bba2c196b5bad1e4c..c77d182faefcbbfd09bf1e8b6c4035e397768ad0 100644 (file)
--- a/src/os/file_windows.go
+++ b/src/os/file_windows.go
@@ -14,7 +14,8 @@ import (
        "unsafe"
 )
 
-const _UTIME_OMIT = 0
+// This matches the value in syscall/syscall_windows.go.
+const _UTIME_OMIT = -1
 
 // file is the real representation of *File.
 // The extra level of indirection ensures that no clients of os

diff --git a/src/os/os_test.go b/src/os/os_test.go
index 3f4fbabb2d35b2f68e36841fb3755ec2a488da42..09d923a33834d10912ef7e4cc6fb3fb35b8c82e7 100644 (file)
--- a/src/os/os_test.go
+++ b/src/os/os_test.go
@@ -1568,6 +1568,32 @@ func testChtimes(t *testing.T, name string) {
        }
 }
 
+func TestChtimesToUnixZero(t *testing.T) {
+       file := newFile("chtimes-to-unix-zero", t)
+       fn := file.Name()
+       defer Remove(fn)
+       if _, err := file.Write([]byte("hi")); err != nil {
+               t.Fatal(err)
+       }
+       if err := file.Close(); err != nil {
+               t.Fatal(err)
+       }
+
+       unixZero := time.Unix(0, 0)
+       if err := Chtimes(fn, unixZero, unixZero); err != nil {
+               t.Fatalf("Chtimes failed: %v", err)
+       }
+
+       st, err := Stat(fn)
+       if err != nil {
+               t.Fatal(err)
+       }
+
+       if mt := st.ModTime(); mt != unixZero {
+               t.Errorf("mtime is %v, want %v", mt, unixZero)
+       }
+}
+
 func TestFileChdir(t *testing.T) {
        wd, err := Getwd()
        if err != nil {

diff --git a/src/syscall/syscall_windows.go b/src/syscall/syscall_windows.go
index c3fa415832ed835ffe33d326b938ef7f91502513..d721309781d2dbfa0627a1540a838c36eeca30b6 100644 (file)
--- a/src/syscall/syscall_windows.go
+++ b/src/syscall/syscall_windows.go
@@ -658,6 +658,9 @@ func Utimes(path string, tv []Timeval) (err error) {
        return SetFileTime(h, nil, &a, &w)
 }
 
+// This matches the value in os/file_windows.go.
+const _UTIME_OMIT = -1
+
 func UtimesNano(path string, ts []Timespec) (err error) {
        if len(ts) != 2 {
                return EINVAL
@@ -675,10 +678,10 @@ func UtimesNano(path string, ts []Timespec) (err error) {
        defer Close(h)
        a := Filetime{}
        w := Filetime{}
-       if TimespecToNsec(ts[0]) != 0 {
+       if ts[0].Nsec != _UTIME_OMIT {
                a = NsecToFiletime(TimespecToNsec(ts[0]))
        }
-       if TimespecToNsec(ts[1]) != 0 {
+       if ts[1].Nsec != _UTIME_OMIT {
                w = NsecToFiletime(TimespecToNsec(ts[1]))
        }
        return SetFileTime(h, nil, &a, &w)