os: don't use test logger for Getwd

Otherwise, on systems for which syscall does not implement Getwd,
a lot of unnecessary files and directories get added to the testlog,
right up the root directory. This was causing tests on such systems
to fail to cache in practice.

Updates #22593

Change-Id: Ic8cb3450ea62aa0ca8eeb15754349f151cd76f85
Reviewed-on: https://go-review.googlesource.com/83455
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

src/os/file.go

@@ -258,6 +258,16 @@ func Create(name string) (*File, error) {
 	return OpenFile(name, O_RDWR|O_CREATE|O_TRUNC, 0666)
 }
 
+// OpenFile is the generalized open call; most users will use Open
+// or Create instead. It opens the named file with specified flag
+// (O_RDONLY etc.) and perm, (0666 etc.) if applicable. If successful,
+// methods on the returned File can be used for I/O.
+// If there is an error, it will be of type *PathError.
+func OpenFile(name string, flag int, perm FileMode) (*File, error) {
+	testlog.Open(name)
+	return openFileNolog(name, flag, perm)
+}
+
 // lstat is overridden in tests.
 var lstat = Lstat
 

src/os/file_plan9.go

@@ -6,7 +6,6 @@ package os
 
 import (
 	"internal/poll"
-	"internal/testlog"
 	"io"
 	"runtime"
 	"syscall"
@@ -80,14 +79,8 @@ func syscallMode(i FileMode) (o uint32) {
 	return
 }
 
-// OpenFile is the generalized open call; most users will use Open
-// or Create instead. It opens the named file with specified flag
-// (O_RDONLY etc.) and perm, (0666 etc.) if applicable. If successful,
-// methods on the returned File can be used for I/O.
-// If there is an error, it will be of type *PathError.
-func OpenFile(name string, flag int, perm FileMode) (*File, error) {
-	testlog.Open(name)
-
+// openFileNolog is the Plan 9 implementation of OpenFile.
+func openFileNolog(name string, flag int, perm FileMode) (*File, error) {
 	var (
 		fd     int
 		e      error

src/os/file_unix.go

@@ -8,7 +8,6 @@ package os
 
 import (
 	"internal/poll"
-	"internal/testlog"
 	"runtime"
 	"syscall"
 )
@@ -154,14 +153,8 @@ func epipecheck(file *File, e error) {
 // On Unix-like systems, it is "/dev/null"; on Windows, "NUL".
 const DevNull = "/dev/null"
 
-// OpenFile is the generalized open call; most users will use Open
-// or Create instead. It opens the named file with specified flag
-// (O_RDONLY etc.) and perm, (0666 etc.) if applicable. If successful,
-// methods on the returned File can be used for I/O.
-// If there is an error, it will be of type *PathError.
-func OpenFile(name string, flag int, perm FileMode) (*File, error) {
-	testlog.Open(name)
-
+// openFileNolog is the Unix implementation of OpenFile.
+func openFileNolog(name string, flag int, perm FileMode) (*File, error) {
 	chmod := false
 	if !supportsCreateWithStickyBit && flag&O_CREATE != 0 && perm&ModeSticky != 0 {
 		if _, err := Stat(name); IsNotExist(err) {

src/os/file_windows.go

@@ -7,7 +7,6 @@ package os
 import (
 	"internal/poll"
 	"internal/syscall/windows"
-	"internal/testlog"
 	"runtime"
 	"syscall"
 	"unicode/utf16"
@@ -149,14 +148,8 @@ func openDir(name string) (file *File, err error) {
 	return f, nil
 }
 
-// OpenFile is the generalized open call; most users will use Open
-// or Create instead. It opens the named file with specified flag
-// (O_RDONLY etc.) and perm, (0666 etc.) if applicable. If successful,
-// methods on the returned File can be used for I/O.
-// If there is an error, it will be of type *PathError.
-func OpenFile(name string, flag int, perm FileMode) (*File, error) {
-	testlog.Open(name)
-
+// openFileNolog is the Windows implementation of OpenFile.
+func openFileNolog(name string, flag int, perm FileMode) (*File, error) {
 	if name == "" {
 		return nil, &PathError{"open", name, syscall.ENOENT}
 	}

src/os/getwd.go

@@ -30,13 +30,13 @@ func Getwd() (dir string, err error) {
 
 	// Clumsy but widespread kludge:
 	// if $PWD is set and matches ".", use it.
-	dot, err := Stat(".")
+	dot, err := statNolog(".")
 	if err != nil {
 		return "", err
 	}
 	dir = Getenv("PWD")
 	if len(dir) > 0 && dir[0] == '/' {
-		d, err := Stat(dir)
+		d, err := statNolog(dir)
 		if err == nil && SameFile(dot, d) {
 			return dir, nil
 		}
@@ -56,15 +56,15 @@ func Getwd() (dir string, err error) {
 	dir = getwdCache.dir
 	getwdCache.Unlock()
 	if len(dir) > 0 {
-		d, err := Stat(dir)
+		d, err := statNolog(dir)
 		if err == nil && SameFile(dot, d) {
 			return dir, nil
 		}
 	}
 
 	// Root is a special case because it has no parent
 	// and ends in a slash.
-	root, err := Stat("/")
+	root, err := statNolog("/")
 	if err != nil {
 		// Can't stat root - no hope.
 		return "", err
@@ -81,7 +81,7 @@ func Getwd() (dir string, err error) {
 		if len(parent) >= 1024 { // Sanity check
 			return "", syscall.ENAMETOOLONG
 		}
-		fd, err := Open(parent)
+		fd, err := openFileNolog(parent, O_RDONLY, 0)
 		if err != nil {
 			return "", err
 		}
@@ -93,7 +93,7 @@ func Getwd() (dir string, err error) {
 				return "", err
 			}
 			for _, name := range names {
-				d, _ := Lstat(parent + "/" + name)
+				d, _ := lstatNolog(parent + "/" + name)
 				if SameFile(d, dot) {
 					dir = "/" + name + dir
 					goto Found

src/os/stat.go

@@ -0,0 +1,23 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package os
+
+import "internal/testlog"
+
+// Stat returns a FileInfo describing the named file.
+// If there is an error, it will be of type *PathError.
+func Stat(name string) (FileInfo, error) {
+	testlog.Stat(name)
+	return statNolog(name)
+}
+
+// Lstat returns a FileInfo describing the named file.
+// If the file is a symbolic link, the returned FileInfo
+// describes the symbolic link. Lstat makes no attempt to follow the link.
+// If there is an error, it will be of type *PathError.
+func Lstat(name string) (FileInfo, error) {
+	testlog.Stat(name)
+	return lstatNolog(name)
+}

src/os/stat_plan9.go

@@ -5,7 +5,6 @@
 package os
 
 import (
-	"internal/testlog"
 	"syscall"
 	"time"
 )
@@ -87,23 +86,18 @@ func dirstat(arg interface{}) (*syscall.Dir, error) {
 	return nil, &PathError{"stat", name, err}
 }
 
-// Stat returns a FileInfo describing the named file.
-// If there is an error, it will be of type *PathError.
-func Stat(name string) (FileInfo, error) {
-	testlog.Stat(name)
+// statNolog implements Stat for Plan 9.
+func statNolog(name string) (FileInfo, error) {
 	d, err := dirstat(name)
 	if err != nil {
 		return nil, err
 	}
 	return fileInfoFromStat(d), nil
 }
 
-// Lstat returns a FileInfo describing the named file.
-// If the file is a symbolic link, the returned FileInfo
-// describes the symbolic link. Lstat makes no attempt to follow the link.
-// If there is an error, it will be of type *PathError.
-func Lstat(name string) (FileInfo, error) {
-	return Stat(name)
+// lstatNolog implements Lstat for Plan 9.
+func lstatNolog(name string) (FileInfo, error) {
+	return statNolog(name)
 }
 
 // For testing.

src/os/stat_unix.go

@@ -7,7 +7,6 @@
 package os
 
 import (
-	"internal/testlog"
 	"syscall"
 )
 
@@ -26,10 +25,8 @@ func (f *File) Stat() (FileInfo, error) {
 	return &fs, nil
 }
 
-// Stat returns a FileInfo describing the named file.
-// If there is an error, it will be of type *PathError.
-func Stat(name string) (FileInfo, error) {
-	testlog.Stat(name)
+// statNolog stats a file with no test logging.
+func statNolog(name string) (FileInfo, error) {
 	var fs fileStat
 	err := syscall.Stat(name, &fs.sys)
 	if err != nil {
@@ -39,12 +36,8 @@ func Stat(name string) (FileInfo, error) {
 	return &fs, nil
 }
 
-// Lstat returns a FileInfo describing the named file.
-// If the file is a symbolic link, the returned FileInfo
-// describes the symbolic link. Lstat makes no attempt to follow the link.
-// If there is an error, it will be of type *PathError.
-func Lstat(name string) (FileInfo, error) {
-	testlog.Stat(name)
+// lstatNolog lstats a file with no test logging.
+func lstatNolog(name string) (FileInfo, error) {
 	var fs fileStat
 	err := syscall.Lstat(name, &fs.sys)
 	if err != nil {

src/os/stat_windows.go

@@ -6,7 +6,6 @@ package os
 
 import (
 	"internal/syscall/windows"
-	"internal/testlog"
 	"syscall"
 	"unsafe"
 )
@@ -57,10 +56,8 @@ func (file *File) Stat() (FileInfo, error) {
 	}, nil
 }
 
-// Stat returns a FileInfo structure describing the named file.
-// If there is an error, it will be of type *PathError.
-func Stat(name string) (FileInfo, error) {
-	testlog.Stat(name)
+// statNolog implements Stat for Windows.
+func statNolog(name string) (FileInfo, error) {
 	if len(name) == 0 {
 		return nil, &PathError{"Stat", name, syscall.Errno(syscall.ERROR_PATH_NOT_FOUND)}
 	}
@@ -158,12 +155,8 @@ func statWithFindFirstFile(name string, namep *uint16) (FileInfo, error) {
 	}, nil
 }
 
-// Lstat returns the FileInfo structure describing the named file.
-// If the file is a symbolic link, the returned FileInfo
-// describes the symbolic link. Lstat makes no attempt to follow the link.
-// If there is an error, it will be of type *PathError.
-func Lstat(name string) (FileInfo, error) {
-	testlog.Stat(name)
+// lstatNolog implements Lstat for Windows.
+func lstatNolog(name string) (FileInfo, error) {
 	if len(name) == 0 {
 		return nil, &PathError{"Lstat", name, syscall.Errno(syscall.ERROR_PATH_NOT_FOUND)}
 	}