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-rw-r--r--src/os/file_windows.go596
1 files changed, 596 insertions, 0 deletions
diff --git a/src/os/file_windows.go b/src/os/file_windows.go
new file mode 100644
index 000000000..2a90a5055
--- /dev/null
+++ b/src/os/file_windows.go
@@ -0,0 +1,596 @@
+// 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 (
+ "io"
+ "runtime"
+ "sync"
+ "syscall"
+ "unicode/utf16"
+ "unicode/utf8"
+ "unsafe"
+)
+
+// File represents an open file descriptor.
+type File struct {
+ *file
+}
+
+// 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 {
+ fd syscall.Handle
+ name string
+ dirinfo *dirInfo // nil unless directory being read
+ l sync.Mutex // used to implement windows pread/pwrite
+
+ // only for console io
+ isConsole bool
+ lastbits []byte // first few bytes of the last incomplete rune in last write
+ readbuf []rune // input console buffer
+}
+
+// Fd returns the Windows handle referencing the open file.
+// The handle is valid only until f.Close is called or f is garbage collected.
+func (file *File) Fd() uintptr {
+ if file == nil {
+ return uintptr(syscall.InvalidHandle)
+ }
+ return uintptr(file.fd)
+}
+
+// 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) *File {
+ f := &File{&file{fd: h, name: name}}
+ var m uint32
+ if syscall.GetConsoleMode(f.fd, &m) == nil {
+ f.isConsole = true
+ }
+ runtime.SetFinalizer(f.file, (*file).close)
+ return f
+}
+
+// NewFile returns a new File with the given file descriptor and name.
+func NewFile(fd uintptr, name string) *File {
+ h := syscall.Handle(fd)
+ if h == syscall.InvalidHandle {
+ return nil
+ }
+ return newFile(h, name)
+}
+
+// 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) {
+}
+
+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(name, flag|syscall.O_CLOEXEC, syscallMode(perm))
+ if e != nil {
+ return nil, e
+ }
+ return NewFile(uintptr(r), name), nil
+}
+
+func openDir(name string) (file *File, err error) {
+ maskp, e := syscall.UTF16PtrFromString(name + `\*`)
+ 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
+ namep, e := syscall.UTF16PtrFromString(name)
+ if e != nil {
+ return nil, e
+ }
+ e = syscall.GetFileAttributesEx(namep, 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 = name
+ if !isAbs(d.path) {
+ d.path, e = syscall.FullPath(d.path)
+ if e != nil {
+ return nil, e
+ }
+ }
+ f := newFile(r, name)
+ f.dirinfo = d
+ 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 *File, err error) {
+ if name == "" {
+ return nil, &PathError{"open", name, 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{"open", name, syscall.EISDIR}
+ }
+ return r, nil
+ }
+ return nil, &PathError{"open", name, errf}
+}
+
+// Close closes the File, rendering it unusable for I/O.
+// It returns an error, if any.
+func (file *File) Close() error {
+ if file == nil {
+ return ErrInvalid
+ }
+ return file.file.close()
+}
+
+func (file *file) close() error {
+ if file == nil {
+ return syscall.EINVAL
+ }
+ if file.isdir() && file.dirinfo.isempty {
+ // "special" empty directories
+ return nil
+ }
+ if file.fd == syscall.InvalidHandle {
+ return syscall.EINVAL
+ }
+ var e error
+ if file.isdir() {
+ e = syscall.FindClose(syscall.Handle(file.fd))
+ } else {
+ e = syscall.CloseHandle(syscall.Handle(file.fd))
+ }
+ var err error
+ if e != nil {
+ err = &PathError{"close", file.name, e}
+ }
+ file.fd = syscall.InvalidHandle // so it can't be closed again
+
+ // no need for a finalizer anymore
+ runtime.SetFinalizer(file, nil)
+ return err
+}
+
+func (file *File) readdir(n int) (fi []FileInfo, err error) {
+ if file == nil {
+ return nil, syscall.EINVAL
+ }
+ if !file.isdir() {
+ return nil, &PathError{"Readdir", file.name, syscall.ENOTDIR}
+ }
+ if !file.dirinfo.isempty && file.fd == syscall.InvalidHandle {
+ return nil, syscall.EINVAL
+ }
+ wantAll := n <= 0
+ size := n
+ if wantAll {
+ n = -1
+ size = 100
+ }
+ fi = make([]FileInfo, 0, size) // Empty with room to grow.
+ d := &file.dirinfo.data
+ for n != 0 && !file.dirinfo.isempty {
+ if file.dirinfo.needdata {
+ e := syscall.FindNextFile(syscall.Handle(file.fd), d)
+ if e != nil {
+ if e == syscall.ERROR_NO_MORE_FILES {
+ break
+ } else {
+ err = &PathError{"FindNextFile", file.name, e}
+ if !wantAll {
+ fi = nil
+ }
+ return
+ }
+ }
+ }
+ file.dirinfo.needdata = true
+ name := string(syscall.UTF16ToString(d.FileName[0:]))
+ if name == "." || name == ".." { // Useless names
+ continue
+ }
+ f := &fileStat{
+ name: name,
+ sys: syscall.Win32FileAttributeData{
+ FileAttributes: d.FileAttributes,
+ CreationTime: d.CreationTime,
+ LastAccessTime: d.LastAccessTime,
+ LastWriteTime: d.LastWriteTime,
+ FileSizeHigh: d.FileSizeHigh,
+ FileSizeLow: d.FileSizeLow,
+ },
+ path: file.dirinfo.path + `\` + name,
+ }
+ n--
+ fi = append(fi, f)
+ }
+ if !wantAll && len(fi) == 0 {
+ return fi, io.EOF
+ }
+ return fi, nil
+}
+
+// readConsole reads utf16 characters from console File,
+// encodes them into utf8 and stores them in buffer b.
+// It returns the number of utf8 bytes read and an error, if any.
+func (f *File) readConsole(b []byte) (n int, err error) {
+ if len(b) == 0 {
+ return 0, nil
+ }
+ if len(f.readbuf) == 0 {
+ // syscall.ReadConsole seems to fail, if given large buffer.
+ // So limit the buffer to 16000 characters.
+ numBytes := len(b)
+ if numBytes > 16000 {
+ numBytes = 16000
+ }
+ // get more input data from os
+ wchars := make([]uint16, numBytes)
+ var p *uint16
+ if len(b) > 0 {
+ p = &wchars[0]
+ }
+ var nw uint32
+ err := syscall.ReadConsole(f.fd, p, uint32(len(wchars)), &nw, nil)
+ if err != nil {
+ return 0, err
+ }
+ f.readbuf = utf16.Decode(wchars[:nw])
+ }
+ for i, r := range f.readbuf {
+ if utf8.RuneLen(r) > len(b) {
+ f.readbuf = f.readbuf[i:]
+ return n, nil
+ }
+ nr := utf8.EncodeRune(b, r)
+ b = b[nr:]
+ n += nr
+ }
+ f.readbuf = nil
+ return n, nil
+}
+
+// read reads up to len(b) bytes from the File.
+// It returns the number of bytes read and an error, if any.
+func (f *File) read(b []byte) (n int, err error) {
+ f.l.Lock()
+ defer f.l.Unlock()
+ if f.isConsole {
+ return f.readConsole(b)
+ }
+ return fixCount(syscall.Read(f.fd, b))
+}
+
+// pread reads len(b) bytes from the File starting at byte offset off.
+// It returns the number of bytes read and the error, if any.
+// EOF is signaled by a zero count with err set to 0.
+func (f *File) pread(b []byte, off int64) (n int, err error) {
+ f.l.Lock()
+ defer f.l.Unlock()
+ curoffset, e := syscall.Seek(f.fd, 0, 1)
+ if e != nil {
+ return 0, e
+ }
+ defer syscall.Seek(f.fd, curoffset, 0)
+ o := syscall.Overlapped{
+ OffsetHigh: uint32(off >> 32),
+ Offset: uint32(off),
+ }
+ var done uint32
+ e = syscall.ReadFile(syscall.Handle(f.fd), b, &done, &o)
+ if e != nil {
+ if e == syscall.ERROR_HANDLE_EOF {
+ // end of file
+ return 0, nil
+ }
+ return 0, e
+ }
+ return int(done), nil
+}
+
+// writeConsole writes len(b) bytes to the console File.
+// It returns the number of bytes written and an error, if any.
+func (f *File) writeConsole(b []byte) (n int, err error) {
+ n = len(b)
+ runes := make([]rune, 0, 256)
+ if len(f.lastbits) > 0 {
+ b = append(f.lastbits, b...)
+ f.lastbits = nil
+
+ }
+ for len(b) >= utf8.UTFMax || utf8.FullRune(b) {
+ r, l := utf8.DecodeRune(b)
+ runes = append(runes, r)
+ b = b[l:]
+ }
+ if len(b) > 0 {
+ f.lastbits = make([]byte, len(b))
+ copy(f.lastbits, b)
+ }
+ // syscall.WriteConsole seems to fail, if given large buffer.
+ // So limit the buffer to 16000 characters. This number was
+ // discovered by experimenting with syscall.WriteConsole.
+ const maxWrite = 16000
+ for len(runes) > 0 {
+ m := len(runes)
+ if m > maxWrite {
+ m = maxWrite
+ }
+ chunk := runes[:m]
+ runes = runes[m:]
+ uint16s := utf16.Encode(chunk)
+ for len(uint16s) > 0 {
+ var written uint32
+ err = syscall.WriteConsole(f.fd, &uint16s[0], uint32(len(uint16s)), &written, nil)
+ if err != nil {
+ return 0, nil
+ }
+ uint16s = uint16s[written:]
+ }
+ }
+ return n, nil
+}
+
+// write writes len(b) bytes to the File.
+// It returns the number of bytes written and an error, if any.
+func (f *File) write(b []byte) (n int, err error) {
+ f.l.Lock()
+ defer f.l.Unlock()
+ if f.isConsole {
+ return f.writeConsole(b)
+ }
+ return fixCount(syscall.Write(f.fd, b))
+}
+
+// pwrite writes len(b) bytes to the File starting at byte offset off.
+// It returns the number of bytes written and an error, if any.
+func (f *File) pwrite(b []byte, off int64) (n int, err error) {
+ f.l.Lock()
+ defer f.l.Unlock()
+ curoffset, e := syscall.Seek(f.fd, 0, 1)
+ if e != nil {
+ return 0, e
+ }
+ defer syscall.Seek(f.fd, curoffset, 0)
+ o := syscall.Overlapped{
+ OffsetHigh: uint32(off >> 32),
+ Offset: uint32(off),
+ }
+ var done uint32
+ e = syscall.WriteFile(syscall.Handle(f.fd), b, &done, &o)
+ if e != nil {
+ return 0, e
+ }
+ return int(done), nil
+}
+
+// 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) {
+ f.l.Lock()
+ defer f.l.Unlock()
+ return syscall.Seek(f.fd, offset, whence)
+}
+
+// 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(name)
+ if e != nil {
+ return &PathError{"remove", name, 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
+ }
+ }
+ }
+ return &PathError{"remove", name, e}
+}
+
+// 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
+
+ // See ../syscall/exec.go for description of lock.
+ syscall.ForkLock.RLock()
+ e := syscall.Pipe(p[0:])
+ if e != nil {
+ syscall.ForkLock.RUnlock()
+ return nil, nil, NewSyscallError("pipe", e)
+ }
+ syscall.CloseOnExec(p[0])
+ syscall.CloseOnExec(p[1])
+ syscall.ForkLock.RUnlock()
+
+ return NewFile(uintptr(p[0]), "|0"), NewFile(uintptr(p[1]), "|1"), nil
+}
+
+// TempDir returns the default directory to use for temporary files.
+func TempDir() string {
+ const pathSep = '\\'
+ dirw := make([]uint16, syscall.MAX_PATH)
+ n, _ := syscall.GetTempPath(uint32(len(dirw)), &dirw[0])
+ if n > uint32(len(dirw)) {
+ dirw = make([]uint16, n)
+ n, _ = syscall.GetTempPath(uint32(len(dirw)), &dirw[0])
+ if n > uint32(len(dirw)) {
+ n = 0
+ }
+ }
+ if n > 0 && dirw[n-1] == pathSep {
+ n--
+ }
+ return string(utf16.Decode(dirw[0: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(newname)
+ if err != nil {
+ return &LinkError{"link", oldname, newname, err}
+ }
+ o, err := syscall.UTF16PtrFromString(oldname)
+ if err != nil {
+ return &LinkError{"link", oldname, newname, err}
+ }
+
+ e := syscall.CreateHardLink(n, o, 0)
+ if e != 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 {
+ // CreateSymbolicLink is not supported before Windows Vista
+ if syscall.LoadCreateSymbolicLink() != nil {
+ return &LinkError{"symlink", oldname, newname, syscall.EWINDOWS}
+ }
+
+ // '/' does not work in link's content
+ oldname = fromSlash(oldname)
+
+ // need the exact location of the oldname when its relative to determine if its a directory
+ destpath := oldname
+ if !isAbs(oldname) {
+ destpath = dirname(newname) + `\` + oldname
+ }
+
+ fi, err := Lstat(destpath)
+ isdir := err == nil && fi.IsDir()
+
+ n, err := syscall.UTF16PtrFromString(newname)
+ if err != nil {
+ return &LinkError{"symlink", oldname, newname, err}
+ }
+ o, err := syscall.UTF16PtrFromString(oldname)
+ if err != nil {
+ return &LinkError{"symlink", oldname, newname, err}
+ }
+
+ var flags uint32
+ if isdir {
+ flags |= syscall.SYMBOLIC_LINK_FLAG_DIRECTORY
+ }
+ err = syscall.CreateSymbolicLink(n, o, flags)
+ if err != nil {
+ return &LinkError{"symlink", oldname, newname, err}
+ }
+ return nil
+}
+
+func fromSlash(path string) string {
+ // Replace each '/' with '\\' if present
+ var pathbuf []byte
+ var lastSlash int
+ for i, b := range path {
+ if b == '/' {
+ if pathbuf == nil {
+ pathbuf = make([]byte, len(path))
+ }
+ copy(pathbuf[lastSlash:], path[lastSlash:i])
+ pathbuf[i] = '\\'
+ lastSlash = i + 1
+ }
+ }
+ if pathbuf == nil {
+ return path
+ }
+
+ copy(pathbuf[lastSlash:], path[lastSlash:])
+ return string(pathbuf)
+}
+
+func dirname(path string) string {
+ vol := volumeName(path)
+ i := len(path) - 1
+ for i >= len(vol) && !IsPathSeparator(path[i]) {
+ i--
+ }
+ dir := path[len(vol) : i+1]
+ last := len(dir) - 1
+ if last > 0 && IsPathSeparator(dir[last]) {
+ dir = dir[:last]
+ }
+ if dir == "" {
+ dir = "."
+ }
+ return vol + dir
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-06-03 07:50:07 +0000