1 files changed, 44 insertions, 16 deletions

diff --git a/libgo/go/os/file_posix.go b/libgo/go/os/file_posix.go
index 6634112..51cae9d 100644
--- a/libgo/go/os/file_posix.go
+++ b/libgo/go/os/file_posix.go
@@ -48,24 +48,21 @@ func syscallMode(i FileMode) (o uint32) {
 	return
 }
 
-// Chmod changes the mode of the named file to mode.
-// If the file is a symbolic link, it changes the mode of the link's target.
-// If there is an error, it will be of type *PathError.
-func Chmod(name string, mode FileMode) error {
-	if e := syscall.Chmod(name, syscallMode(mode)); e != nil {
+// See docs in file.go:Chmod.
+func chmod(name string, mode FileMode) error {
+	if e := syscall.Chmod(fixLongPath(name), syscallMode(mode)); e != nil {
 		return &PathError{"chmod", name, e}
 	}
 	return nil
 }
 
-// Chmod changes the mode of the file to mode.
-// If there is an error, it will be of type *PathError.
-func (f *File) Chmod(mode FileMode) error {
+// See docs in file.go:(*File).Chmod.
+func (f *File) chmod(mode FileMode) error {
 	if err := f.checkValid("chmod"); err != nil {
 		return err
 	}
-	if e := syscall.Fchmod(f.fd, syscallMode(mode)); e != nil {
-		return &PathError{"chmod", f.name, e}
+	if e := f.pfd.Fchmod(syscallMode(mode)); e != nil {
+		return f.wrapErr("chmod", e)
 	}
 	return nil
 }
@@ -73,6 +70,9 @@ func (f *File) Chmod(mode FileMode) error {
 // Chown changes the numeric uid and gid of the named file.
 // If the file is a symbolic link, it changes the uid and gid of the link's target.
 // If there is an error, it will be of type *PathError.
+//
+// On Windows, it always returns the syscall.EWINDOWS error, wrapped
+// in *PathError.
 func Chown(name string, uid, gid int) error {
 	if e := syscall.Chown(name, uid, gid); e != nil {
 		return &PathError{"chown", name, e}
@@ -83,6 +83,9 @@ func Chown(name string, uid, gid int) error {
 // Lchown changes the numeric uid and gid of the named file.
 // If the file is a symbolic link, it changes the uid and gid of the link itself.
 // If there is an error, it will be of type *PathError.
+//
+// On Windows, it always returns the syscall.EWINDOWS error, wrapped
+// in *PathError.
 func Lchown(name string, uid, gid int) error {
 	if e := syscall.Lchown(name, uid, gid); e != nil {
 		return &PathError{"lchown", name, e}
@@ -92,12 +95,15 @@ func Lchown(name string, uid, gid int) error {
 
 // Chown changes the numeric uid and gid of the named file.
 // If there is an error, it will be of type *PathError.
+//
+// On Windows, it always returns the syscall.EWINDOWS error, wrapped
+// in *PathError.
 func (f *File) Chown(uid, gid int) error {
 	if err := f.checkValid("chown"); err != nil {
 		return err
 	}
-	if e := syscall.Fchown(f.fd, uid, gid); e != nil {
-		return &PathError{"chown", f.name, e}
+	if e := f.pfd.Fchown(uid, gid); e != nil {
+		return f.wrapErr("chown", e)
 	}
 	return nil
 }
@@ -109,8 +115,8 @@ func (f *File) Truncate(size int64) error {
 	if err := f.checkValid("truncate"); err != nil {
 		return err
 	}
-	if e := syscall.Ftruncate(f.fd, size); e != nil {
-		return &PathError{"truncate", f.name, e}
+	if e := f.pfd.Ftruncate(size); e != nil {
+		return f.wrapErr("truncate", e)
 	}
 	return nil
 }
@@ -122,8 +128,8 @@ func (f *File) Sync() error {
 	if err := f.checkValid("sync"); err != nil {
 		return err
 	}
-	if e := syscall.Fsync(f.fd); e != nil {
-		return &PathError{"sync", f.name, e}
+	if e := f.pfd.Fsync(); e != nil {
+		return f.wrapErr("sync", e)
 	}
 	return nil
 }
@@ -143,3 +149,25 @@ func Chtimes(name string, atime time.Time, mtime time.Time) error {
 	}
 	return nil
 }
+
+// Chdir changes the current working directory to the file,
+// which must be a directory.
+// If there is an error, it will be of type *PathError.
+func (f *File) Chdir() error {
+	if err := f.checkValid("chdir"); err != nil {
+		return err
+	}
+	if e := f.pfd.Fchdir(); e != nil {
+		return f.wrapErr("chdir", e)
+	}
+	return nil
+}
+
+// checkValid checks whether f is valid for use.
+// If not, it returns an appropriate error, perhaps incorporating the operation name op.
+func (f *File) checkValid(op string) error {
+	if f == nil {
+		return ErrInvalid
+	}
+	return nil
+}