syscall: correct Win32finddata definition

Fixes #3685.

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/6261053

api/next.txt

@@ -422,12 +422,38 @@ pkg syscall (darwin-amd64-cgo), type Termios struct, Pad_cgo_0 [4]byte
 pkg syscall (windows-386), const CREATE_NEW_PROCESS_GROUP ideal-int
 pkg syscall (windows-386), const CTRL_BREAK_EVENT ideal-int
 pkg syscall (windows-386), const CTRL_C_EVENT ideal-int
+pkg syscall (windows-386), func FindFirstFile1(*uint16, *Win32finddata1) (Handle, error)
+pkg syscall (windows-386), func FindNextFile1(Handle, *Win32finddata1) error
 pkg syscall (windows-386), func GetCurrentProcessId() uint32
 pkg syscall (windows-386), func Getsockopt(Handle, int32, int32, *byte, *int32) error
 pkg syscall (windows-386), type SysProcAttr struct, CreationFlags uint32
+pkg syscall (windows-386), type Win32finddata1 struct
+pkg syscall (windows-386), type Win32finddata1 struct, AlternateFileName [14]uint16
+pkg syscall (windows-386), type Win32finddata1 struct, CreationTime Filetime
+pkg syscall (windows-386), type Win32finddata1 struct, FileAttributes uint32
+pkg syscall (windows-386), type Win32finddata1 struct, FileName [MAX_PATH]uint16
+pkg syscall (windows-386), type Win32finddata1 struct, FileSizeHigh uint32
+pkg syscall (windows-386), type Win32finddata1 struct, FileSizeLow uint32
+pkg syscall (windows-386), type Win32finddata1 struct, LastAccessTime Filetime
+pkg syscall (windows-386), type Win32finddata1 struct, LastWriteTime Filetime
+pkg syscall (windows-386), type Win32finddata1 struct, Reserved0 uint32
+pkg syscall (windows-386), type Win32finddata1 struct, Reserved1 uint32
 pkg syscall (windows-amd64), const CREATE_NEW_PROCESS_GROUP ideal-int
 pkg syscall (windows-amd64), const CTRL_BREAK_EVENT ideal-int
 pkg syscall (windows-amd64), const CTRL_C_EVENT ideal-int
+pkg syscall (windows-amd64), func FindFirstFile1(*uint16, *Win32finddata1) (Handle, error)
+pkg syscall (windows-amd64), func FindNextFile1(Handle, *Win32finddata1) error
 pkg syscall (windows-amd64), func GetCurrentProcessId() uint32
 pkg syscall (windows-amd64), func Getsockopt(Handle, int32, int32, *byte, *int32) error
 pkg syscall (windows-amd64), type SysProcAttr struct, CreationFlags uint32
+pkg syscall (windows-amd64), type Win32finddata1 struct
+pkg syscall (windows-amd64), type Win32finddata1 struct, AlternateFileName [14]uint16
+pkg syscall (windows-amd64), type Win32finddata1 struct, CreationTime Filetime
+pkg syscall (windows-amd64), type Win32finddata1 struct, FileAttributes uint32
+pkg syscall (windows-amd64), type Win32finddata1 struct, FileName [MAX_PATH]uint16
+pkg syscall (windows-amd64), type Win32finddata1 struct, FileSizeHigh uint32
+pkg syscall (windows-amd64), type Win32finddata1 struct, FileSizeLow uint32
+pkg syscall (windows-amd64), type Win32finddata1 struct, LastAccessTime Filetime
+pkg syscall (windows-amd64), type Win32finddata1 struct, LastWriteTime Filetime
+pkg syscall (windows-amd64), type Win32finddata1 struct, Reserved0 uint32
+pkg syscall (windows-amd64), type Win32finddata1 struct, Reserved1 uint32

src/pkg/os/file_windows.go

@@ -50,7 +50,7 @@ func NewFile(fd uintptr, name string) *File {
 
 // Auxiliary information if the File describes a directory
 type dirInfo struct {
-	data     syscall.Win32finddata
+	data     syscall.Win32finddata1
 	needdata bool
 	path     string
 }
@@ -76,7 +76,7 @@ func openFile(name string, flag int, perm FileMode) (file *File, err error) {
 
 func openDir(name string) (file *File, err error) {
 	d := new(dirInfo)
-	r, e := syscall.FindFirstFile(syscall.StringToUTF16Ptr(name+`\*`), &d.data)
+	r, e := syscall.FindFirstFile1(syscall.StringToUTF16Ptr(name+`\*`), &d.data)
 	if e != nil {
 		return nil, &PathError{"open", name, e}
 	}
@@ -159,7 +159,7 @@ func (file *File) readdir(n int) (fi []FileInfo, err error) {
 	d := &file.dirinfo.data
 	for n != 0 {
 		if file.dirinfo.needdata {
-			e := syscall.FindNextFile(syscall.Handle(file.fd), d)
+			e := syscall.FindNextFile1(syscall.Handle(file.fd), d)
 			if e != nil {
 				if e == syscall.ERROR_NO_MORE_FILES {
 					break

src/pkg/syscall/syscall_windows.go

@@ -7,6 +7,7 @@
 package syscall
 
 import (
+	errorspkg "errors"
 	"unicode/utf16"
 	"unsafe"
 )
@@ -129,8 +130,8 @@ func NewCallback(fn interface{}) uintptr
 //sys	SetFilePointer(handle Handle, lowoffset int32, highoffsetptr *int32, whence uint32) (newlowoffset uint32, err error) [failretval==0xffffffff]
 //sys	CloseHandle(handle Handle) (err error)
 //sys	GetStdHandle(stdhandle int) (handle Handle, err error) [failretval==InvalidHandle]
-//sys	FindFirstFile(name *uint16, data *Win32finddata) (handle Handle, err error) [failretval==InvalidHandle] = FindFirstFileW
-//sys	FindNextFile(handle Handle, data *Win32finddata) (err error) = FindNextFileW
+//sys	FindFirstFile1(name *uint16, data *Win32finddata1) (handle Handle, err error) [failretval==InvalidHandle] = FindFirstFileW
+//sys	FindNextFile1(handle Handle, data *Win32finddata1) (err error) = FindNextFileW
 //sys	FindClose(handle Handle) (err error)
 //sys	GetFileInformationByHandle(handle Handle, data *ByHandleFileInformation) (err error)
 //sys	GetCurrentDirectory(buflen uint32, buf *uint16) (n uint32, err error) = GetCurrentDirectoryW
@@ -704,6 +705,14 @@ func SetsockoptIPv6Mreq(fd Handle, level, opt int, mreq *IPv6Mreq) (err error) {
 
 func Getpid() (pid int) { return int(GetCurrentProcessId()) }
 
+func FindFirstFile(name *uint16, data *Win32finddata) (handle Handle, err error) {
+	return InvalidHandle, errorspkg.New("FindFirstFile is broken, use FindFirstFile1 instead")
+}
+
+func FindNextFile(handle Handle, data *Win32finddata) (err error) {
+	return errorspkg.New("FindNextFile is broken, use FindNextFile1 instead")
+}
+
 // TODO(brainman): fix all needed for os
 func Getppid() (ppid int) { return -1 }
 

src/pkg/syscall/syscall_windows_test.go

+// Copyright 2012 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 syscall_test
+
+import (
+	"io/ioutil"
+	"os"
+	"path/filepath"
+	"syscall"
+	"testing"
+)
+
+func TestWin32finddata(t *testing.T) {
+	dir, err := ioutil.TempDir("", "go-build")
+	if err != nil {
+		t.Fatalf("failed to create temp directory: %v", err)
+	}
+	defer os.RemoveAll(dir)
+
+	path := filepath.Join(dir, "long_name.and_extension")
+	f, err := os.Create(path)
+	if err != nil {
+		t.Fatalf("failed to create %v: %v", path, err)
+	}
+	f.Close()
+
+	type X struct {
+		fd  syscall.Win32finddata1
+		got byte
+		pad [10]byte // to protect ourselves
+
+	}
+	var want byte = 2 // it is unlikely to have this character in the filename
+	x := X{got: want}
+
+	h, err := syscall.FindFirstFile1(syscall.StringToUTF16Ptr(path), &(x.fd))
+	if err != nil {
+		t.Fatalf("FindFirstFile failed: %v", err)
+	}
+	err = syscall.FindClose(h)
+	if err != nil {
+		t.Fatalf("FindClose failed: %v", err)
+	}
+
+	if x.got != want {
+		t.Fatalf("memory corruption: want=%d got=%d", want, x.got)
+	}
+}

src/pkg/syscall/zsyscall_windows_386.go

@@ -310,7 +310,7 @@ func GetStdHandle(stdhandle int) (handle Handle, err error) {
 	return
 }
 
-func FindFirstFile(name *uint16, data *Win32finddata) (handle Handle, err error) {
+func FindFirstFile1(name *uint16, data *Win32finddata1) (handle Handle, err error) {
 	r0, _, e1 := Syscall(procFindFirstFileW.Addr(), 2, uintptr(unsafe.Pointer(name)), uintptr(unsafe.Pointer(data)), 0)
 	handle = Handle(r0)
 	if handle == InvalidHandle {
@@ -323,7 +323,7 @@ func FindFirstFile(name *uint16, data *Win32finddata) (handle Handle, err error)
 	return
 }
 
-func FindNextFile(handle Handle, data *Win32finddata) (err error) {
+func FindNextFile1(handle Handle, data *Win32finddata1) (err error) {
 	r1, _, e1 := Syscall(procFindNextFileW.Addr(), 2, uintptr(handle), uintptr(unsafe.Pointer(data)), 0)
 	if int(r1) == 0 {
 		if e1 != 0 {

src/pkg/syscall/zsyscall_windows_amd64.go

@@ -310,7 +310,7 @@ func GetStdHandle(stdhandle int) (handle Handle, err error) {
 	return
 }
 
-func FindFirstFile(name *uint16, data *Win32finddata) (handle Handle, err error) {
+func FindFirstFile1(name *uint16, data *Win32finddata1) (handle Handle, err error) {
 	r0, _, e1 := Syscall(procFindFirstFileW.Addr(), 2, uintptr(unsafe.Pointer(name)), uintptr(unsafe.Pointer(data)), 0)
 	handle = Handle(r0)
 	if handle == InvalidHandle {
@@ -323,7 +323,7 @@ func FindFirstFile(name *uint16, data *Win32finddata) (handle Handle, err error)
 	return
 }
 
-func FindNextFile(handle Handle, data *Win32finddata) (err error) {
+func FindNextFile1(handle Handle, data *Win32finddata1) (err error) {
 	r1, _, e1 := Syscall(procFindNextFileW.Addr(), 2, uintptr(handle), uintptr(unsafe.Pointer(data)), 0)
 	if int(r1) == 0 {
 		if e1 != 0 {

src/pkg/syscall/ztypes_windows.go

@@ -338,6 +338,9 @@ func NsecToFiletime(nsec int64) (ft Filetime) {
 	return ft
 }
 
+// Win32finddata is an incorrect struct definition, preserved for
+// backwards compatibility. Use Win32finddata1 and the
+// FindFirstFile1 and FindNextFile1 functions instead.
 type Win32finddata struct {
 	FileAttributes    uint32
 	CreationTime      Filetime
@@ -351,6 +354,19 @@ type Win32finddata struct {
 	AlternateFileName [13]uint16
 }
 
+type Win32finddata1 struct {
+	FileAttributes    uint32
+	CreationTime      Filetime
+	LastAccessTime    Filetime
+	LastWriteTime     Filetime
+	FileSizeHigh      uint32
+	FileSizeLow       uint32
+	Reserved0         uint32
+	Reserved1         uint32
+	FileName          [MAX_PATH]uint16
+	AlternateFileName [14]uint16
+}
+
 type ByHandleFileInformation struct {
 	FileAttributes     uint32
 	CreationTime       Filetime