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-rw-r--r--src/os/file_windows.go499
1 files changed, 499 insertions, 0 deletions
diff --git a/src/os/file_windows.go b/src/os/file_windows.go
new file mode 100644
index 0000000..dfc5fc6
--- /dev/null
+++ b/src/os/file_windows.go
@@ -0,0 +1,499 @@
+// Copyright 2009 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 (
+ "errors"
+ "internal/poll"
+ "internal/syscall/windows"
+ "runtime"
+ "syscall"
+ "unicode/utf16"
+ "unsafe"
+)
+
+// file is the real representation of *File.
+// The extra level of indirection ensures that no clients of os
+// can overwrite this data, which could cause the finalizer
+// to close the wrong file descriptor.
+type file struct {
+ pfd poll.FD
+ name string
+ dirinfo *dirInfo // nil unless directory being read
+ appendMode bool // whether file is opened for appending
+}
+
+// Fd returns the Windows handle referencing the open file.
+// If f is closed, the file descriptor becomes invalid.
+// If f is garbage collected, a finalizer may close the file descriptor,
+// making it invalid; see runtime.SetFinalizer for more information on when
+// a finalizer might be run. On Unix systems this will cause the SetDeadline
+// methods to stop working.
+func (file *File) Fd() uintptr {
+ if file == nil {
+ return uintptr(syscall.InvalidHandle)
+ }
+ return uintptr(file.pfd.Sysfd)
+}
+
+// newFile returns a new File with the given file handle and name.
+// Unlike NewFile, it does not check that h is syscall.InvalidHandle.
+func newFile(h syscall.Handle, name string, kind string) *File {
+ if kind == "file" {
+ var m uint32
+ if syscall.GetConsoleMode(h, &m) == nil {
+ kind = "console"
+ }
+ if t, err := syscall.GetFileType(h); err == nil && t == syscall.FILE_TYPE_PIPE {
+ kind = "pipe"
+ }
+ }
+
+ f := &File{&file{
+ pfd: poll.FD{
+ Sysfd: h,
+ IsStream: true,
+ ZeroReadIsEOF: true,
+ },
+ name: name,
+ }}
+ runtime.SetFinalizer(f.file, (*file).close)
+
+ // Ignore initialization errors.
+ // Assume any problems will show up in later I/O.
+ f.pfd.Init(kind, false)
+
+ return f
+}
+
+// newConsoleFile creates new File that will be used as console.
+func newConsoleFile(h syscall.Handle, name string) *File {
+ return newFile(h, name, "console")
+}
+
+// NewFile returns a new File with the given file descriptor and
+// name. The returned value will be nil if fd is not a valid file
+// descriptor.
+func NewFile(fd uintptr, name string) *File {
+ h := syscall.Handle(fd)
+ if h == syscall.InvalidHandle {
+ return nil
+ }
+ return newFile(h, name, "file")
+}
+
+// Auxiliary information if the File describes a directory
+type dirInfo struct {
+ data syscall.Win32finddata
+ needdata bool
+ path string
+ isempty bool // set if FindFirstFile returns ERROR_FILE_NOT_FOUND
+}
+
+func epipecheck(file *File, e error) {
+}
+
+// DevNull is the name of the operating system's ``null device.''
+// On Unix-like systems, it is "/dev/null"; on Windows, "NUL".
+const DevNull = "NUL"
+
+func (f *file) isdir() bool { return f != nil && f.dirinfo != nil }
+
+func openFile(name string, flag int, perm FileMode) (file *File, err error) {
+ r, e := syscall.Open(fixLongPath(name), flag|syscall.O_CLOEXEC, syscallMode(perm))
+ if e != nil {
+ return nil, e
+ }
+ return newFile(r, name, "file"), nil
+}
+
+func openDir(name string) (file *File, err error) {
+ var mask string
+
+ path := fixLongPath(name)
+
+ if len(path) == 2 && path[1] == ':' { // it is a drive letter, like C:
+ mask = path + `*`
+ } else if len(path) > 0 {
+ lc := path[len(path)-1]
+ if lc == '/' || lc == '\\' {
+ mask = path + `*`
+ } else {
+ mask = path + `\*`
+ }
+ } else {
+ mask = `\*`
+ }
+ maskp, e := syscall.UTF16PtrFromString(mask)
+ if e != nil {
+ return nil, e
+ }
+ d := new(dirInfo)
+ r, e := syscall.FindFirstFile(maskp, &d.data)
+ if e != nil {
+ // FindFirstFile returns ERROR_FILE_NOT_FOUND when
+ // no matching files can be found. Then, if directory
+ // exists, we should proceed.
+ if e != syscall.ERROR_FILE_NOT_FOUND {
+ return nil, e
+ }
+ var fa syscall.Win32FileAttributeData
+ pathp, e := syscall.UTF16PtrFromString(path)
+ if e != nil {
+ return nil, e
+ }
+ e = syscall.GetFileAttributesEx(pathp, syscall.GetFileExInfoStandard, (*byte)(unsafe.Pointer(&fa)))
+ if e != nil {
+ return nil, e
+ }
+ if fa.FileAttributes&syscall.FILE_ATTRIBUTE_DIRECTORY == 0 {
+ return nil, e
+ }
+ d.isempty = true
+ }
+ d.path = path
+ if !isAbs(d.path) {
+ d.path, e = syscall.FullPath(d.path)
+ if e != nil {
+ return nil, e
+ }
+ }
+ f := newFile(r, name, "dir")
+ f.dirinfo = d
+ return f, nil
+}
+
+// openFileNolog is the Windows implementation of OpenFile.
+func openFileNolog(name string, flag int, perm FileMode) (*File, error) {
+ if name == "" {
+ return nil, &PathError{Op: "open", Path: name, Err: syscall.ENOENT}
+ }
+ r, errf := openFile(name, flag, perm)
+ if errf == nil {
+ return r, nil
+ }
+ r, errd := openDir(name)
+ if errd == nil {
+ if flag&O_WRONLY != 0 || flag&O_RDWR != 0 {
+ r.Close()
+ return nil, &PathError{Op: "open", Path: name, Err: syscall.EISDIR}
+ }
+ return r, nil
+ }
+ return nil, &PathError{Op: "open", Path: name, Err: errf}
+}
+
+func (file *file) close() error {
+ if file == nil {
+ return syscall.EINVAL
+ }
+ if file.isdir() && file.dirinfo.isempty {
+ // "special" empty directories
+ return nil
+ }
+ var err error
+ if e := file.pfd.Close(); e != nil {
+ if e == poll.ErrFileClosing {
+ e = ErrClosed
+ }
+ err = &PathError{Op: "close", Path: file.name, Err: e}
+ }
+
+ // no need for a finalizer anymore
+ runtime.SetFinalizer(file, nil)
+ return err
+}
+
+// seek sets the offset for the next Read or Write on file to offset, interpreted
+// according to whence: 0 means relative to the origin of the file, 1 means
+// relative to the current offset, and 2 means relative to the end.
+// It returns the new offset and an error, if any.
+func (f *File) seek(offset int64, whence int) (ret int64, err error) {
+ ret, err = f.pfd.Seek(offset, whence)
+ runtime.KeepAlive(f)
+ return ret, err
+}
+
+// Truncate changes the size of the named file.
+// If the file is a symbolic link, it changes the size of the link's target.
+func Truncate(name string, size int64) error {
+ f, e := OpenFile(name, O_WRONLY|O_CREATE, 0666)
+ if e != nil {
+ return e
+ }
+ defer f.Close()
+ e1 := f.Truncate(size)
+ if e1 != nil {
+ return e1
+ }
+ return nil
+}
+
+// Remove removes the named file or directory.
+// If there is an error, it will be of type *PathError.
+func Remove(name string) error {
+ p, e := syscall.UTF16PtrFromString(fixLongPath(name))
+ if e != nil {
+ return &PathError{Op: "remove", Path: name, Err: e}
+ }
+
+ // Go file interface forces us to know whether
+ // name is a file or directory. Try both.
+ e = syscall.DeleteFile(p)
+ if e == nil {
+ return nil
+ }
+ e1 := syscall.RemoveDirectory(p)
+ if e1 == nil {
+ return nil
+ }
+
+ // Both failed: figure out which error to return.
+ if e1 != e {
+ a, e2 := syscall.GetFileAttributes(p)
+ if e2 != nil {
+ e = e2
+ } else {
+ if a&syscall.FILE_ATTRIBUTE_DIRECTORY != 0 {
+ e = e1
+ } else if a&syscall.FILE_ATTRIBUTE_READONLY != 0 {
+ if e1 = syscall.SetFileAttributes(p, a&^syscall.FILE_ATTRIBUTE_READONLY); e1 == nil {
+ if e = syscall.DeleteFile(p); e == nil {
+ return nil
+ }
+ }
+ }
+ }
+ }
+ return &PathError{Op: "remove", Path: name, Err: e}
+}
+
+func rename(oldname, newname string) error {
+ e := windows.Rename(fixLongPath(oldname), fixLongPath(newname))
+ if e != nil {
+ return &LinkError{"rename", oldname, newname, e}
+ }
+ return nil
+}
+
+// Pipe returns a connected pair of Files; reads from r return bytes written to w.
+// It returns the files and an error, if any.
+func Pipe() (r *File, w *File, err error) {
+ var p [2]syscall.Handle
+ e := syscall.CreatePipe(&p[0], &p[1], nil, 0)
+ if e != nil {
+ return nil, nil, NewSyscallError("pipe", e)
+ }
+ return newFile(p[0], "|0", "pipe"), newFile(p[1], "|1", "pipe"), nil
+}
+
+func tempDir() string {
+ n := uint32(syscall.MAX_PATH)
+ for {
+ b := make([]uint16, n)
+ n, _ = syscall.GetTempPath(uint32(len(b)), &b[0])
+ if n > uint32(len(b)) {
+ continue
+ }
+ if n == 3 && b[1] == ':' && b[2] == '\\' {
+ // Do nothing for path, like C:\.
+ } else if n > 0 && b[n-1] == '\\' {
+ // Otherwise remove terminating \.
+ n--
+ }
+ return string(utf16.Decode(b[:n]))
+ }
+}
+
+// Link creates newname as a hard link to the oldname file.
+// If there is an error, it will be of type *LinkError.
+func Link(oldname, newname string) error {
+ n, err := syscall.UTF16PtrFromString(fixLongPath(newname))
+ if err != nil {
+ return &LinkError{"link", oldname, newname, err}
+ }
+ o, err := syscall.UTF16PtrFromString(fixLongPath(oldname))
+ if err != nil {
+ return &LinkError{"link", oldname, newname, err}
+ }
+ err = syscall.CreateHardLink(n, o, 0)
+ if err != nil {
+ return &LinkError{"link", oldname, newname, err}
+ }
+ return nil
+}
+
+// Symlink creates newname as a symbolic link to oldname.
+// If there is an error, it will be of type *LinkError.
+func Symlink(oldname, newname string) error {
+ // '/' does not work in link's content
+ oldname = fromSlash(oldname)
+
+ // need the exact location of the oldname when it's relative to determine if it's a directory
+ destpath := oldname
+ if v := volumeName(oldname); v == "" {
+ if len(oldname) > 0 && IsPathSeparator(oldname[0]) {
+ // oldname is relative to the volume containing newname.
+ if v = volumeName(newname); v != "" {
+ // Prepend the volume explicitly, because it may be different from the
+ // volume of the current working directory.
+ destpath = v + oldname
+ }
+ } else {
+ // oldname is relative to newname.
+ destpath = dirname(newname) + `\` + oldname
+ }
+ }
+
+ fi, err := Stat(destpath)
+ isdir := err == nil && fi.IsDir()
+
+ n, err := syscall.UTF16PtrFromString(fixLongPath(newname))
+ if err != nil {
+ return &LinkError{"symlink", oldname, newname, err}
+ }
+ o, err := syscall.UTF16PtrFromString(fixLongPath(oldname))
+ if err != nil {
+ return &LinkError{"symlink", oldname, newname, err}
+ }
+
+ var flags uint32 = windows.SYMBOLIC_LINK_FLAG_ALLOW_UNPRIVILEGED_CREATE
+ if isdir {
+ flags |= syscall.SYMBOLIC_LINK_FLAG_DIRECTORY
+ }
+ err = syscall.CreateSymbolicLink(n, o, flags)
+
+ if err != nil {
+ // the unprivileged create flag is unsupported
+ // below Windows 10 (1703, v10.0.14972). retry without it.
+ flags &^= windows.SYMBOLIC_LINK_FLAG_ALLOW_UNPRIVILEGED_CREATE
+
+ err = syscall.CreateSymbolicLink(n, o, flags)
+ }
+
+ if err != nil {
+ return &LinkError{"symlink", oldname, newname, err}
+ }
+ return nil
+}
+
+// openSymlink calls CreateFile Windows API with FILE_FLAG_OPEN_REPARSE_POINT
+// parameter, so that Windows does not follow symlink, if path is a symlink.
+// openSymlink returns opened file handle.
+func openSymlink(path string) (syscall.Handle, error) {
+ p, err := syscall.UTF16PtrFromString(path)
+ if err != nil {
+ return 0, err
+ }
+ attrs := uint32(syscall.FILE_FLAG_BACKUP_SEMANTICS)
+ // Use FILE_FLAG_OPEN_REPARSE_POINT, otherwise CreateFile will follow symlink.
+ // See https://docs.microsoft.com/en-us/windows/desktop/FileIO/symbolic-link-effects-on-file-systems-functions#createfile-and-createfiletransacted
+ attrs |= syscall.FILE_FLAG_OPEN_REPARSE_POINT
+ h, err := syscall.CreateFile(p, 0, 0, nil, syscall.OPEN_EXISTING, attrs, 0)
+ if err != nil {
+ return 0, err
+ }
+ return h, nil
+}
+
+// normaliseLinkPath converts absolute paths returned by
+// DeviceIoControl(h, FSCTL_GET_REPARSE_POINT, ...)
+// into paths acceptable by all Windows APIs.
+// For example, it coverts
+// \??\C:\foo\bar into C:\foo\bar
+// \??\UNC\foo\bar into \\foo\bar
+// \??\Volume{abc}\ into C:\
+func normaliseLinkPath(path string) (string, error) {
+ if len(path) < 4 || path[:4] != `\??\` {
+ // unexpected path, return it as is
+ return path, nil
+ }
+ // we have path that start with \??\
+ s := path[4:]
+ switch {
+ case len(s) >= 2 && s[1] == ':': // \??\C:\foo\bar
+ return s, nil
+ case len(s) >= 4 && s[:4] == `UNC\`: // \??\UNC\foo\bar
+ return `\\` + s[4:], nil
+ }
+
+ // handle paths, like \??\Volume{abc}\...
+
+ err := windows.LoadGetFinalPathNameByHandle()
+ if err != nil {
+ // we must be using old version of Windows
+ return "", err
+ }
+
+ h, err := openSymlink(path)
+ if err != nil {
+ return "", err
+ }
+ defer syscall.CloseHandle(h)
+
+ buf := make([]uint16, 100)
+ for {
+ n, err := windows.GetFinalPathNameByHandle(h, &buf[0], uint32(len(buf)), windows.VOLUME_NAME_DOS)
+ if err != nil {
+ return "", err
+ }
+ if n < uint32(len(buf)) {
+ break
+ }
+ buf = make([]uint16, n)
+ }
+ s = syscall.UTF16ToString(buf)
+ if len(s) > 4 && s[:4] == `\\?\` {
+ s = s[4:]
+ if len(s) > 3 && s[:3] == `UNC` {
+ // return path like \\server\share\...
+ return `\` + s[3:], nil
+ }
+ return s, nil
+ }
+ return "", errors.New("GetFinalPathNameByHandle returned unexpected path: " + s)
+}
+
+func readlink(path string) (string, error) {
+ h, err := openSymlink(path)
+ if err != nil {
+ return "", err
+ }
+ defer syscall.CloseHandle(h)
+
+ rdbbuf := make([]byte, syscall.MAXIMUM_REPARSE_DATA_BUFFER_SIZE)
+ var bytesReturned uint32
+ err = syscall.DeviceIoControl(h, syscall.FSCTL_GET_REPARSE_POINT, nil, 0, &rdbbuf[0], uint32(len(rdbbuf)), &bytesReturned, nil)
+ if err != nil {
+ return "", err
+ }
+
+ rdb := (*windows.REPARSE_DATA_BUFFER)(unsafe.Pointer(&rdbbuf[0]))
+ switch rdb.ReparseTag {
+ case syscall.IO_REPARSE_TAG_SYMLINK:
+ rb := (*windows.SymbolicLinkReparseBuffer)(unsafe.Pointer(&rdb.DUMMYUNIONNAME))
+ s := rb.Path()
+ if rb.Flags&windows.SYMLINK_FLAG_RELATIVE != 0 {
+ return s, nil
+ }
+ return normaliseLinkPath(s)
+ case windows.IO_REPARSE_TAG_MOUNT_POINT:
+ return normaliseLinkPath((*windows.MountPointReparseBuffer)(unsafe.Pointer(&rdb.DUMMYUNIONNAME)).Path())
+ default:
+ // the path is not a symlink or junction but another type of reparse
+ // point
+ return "", syscall.ENOENT
+ }
+}
+
+// Readlink returns the destination of the named symbolic link.
+// If there is an error, it will be of type *PathError.
+func Readlink(name string) (string, error) {
+ s, err := readlink(fixLongPath(name))
+ if err != nil {
+ return "", &PathError{Op: "readlink", Path: name, Err: err}
+ }
+ return s, nil
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-15 11:05:04 +0000