tinygo/src/os/file_windows.go
ZauberNerd 3f69c32a55 src/os: export correct values for os.DevNull for each OS
This commit introduces `os.DevNull` exports for all supported OS
targets.
2022-03-08 14:49:14 +01:00

106 строки
2,5 КиБ
Go

//go:build windows
// +build windows
// Portions 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 (
"internal/syscall/windows"
"syscall"
"unicode/utf16"
)
const DevNull = "NUL"
type syscallFd = syscall.Handle
// Symlink is a stub, it is not implemented.
func Symlink(oldname, newname string) error {
return ErrNotImplemented
}
// Readlink is a stub (for now), always returning the string it was given
func Readlink(name string) (string, error) {
return name, nil
}
func rename(oldname, newname string) error {
e := windows.Rename(fixLongPath(oldname), fixLongPath(newname))
if e != nil {
return &LinkError{"rename", oldname, newname, e}
}
return nil
}
type file struct {
handle FileHandle
name string
}
func NewFile(fd uintptr, name string) *File {
return &File{&file{unixFileHandle(fd), name}}
}
func Pipe() (r *File, w *File, err error) {
var p [2]syscall.Handle
e := handleSyscallError(syscall.Pipe(p[:]))
if e != nil {
return nil, nil, err
}
r = NewFile(uintptr(p[0]), "|0")
w = NewFile(uintptr(p[1]), "|1")
return
}
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]))
}
}
// ReadAt reads up to len(b) bytes from the File starting at the given absolute offset.
// It returns the number of bytes read and any error encountered, possibly io.EOF.
// At end of file, Pread returns 0, io.EOF.
// TODO: move to file_anyos once ReadAt is implemented for windows
func (f unixFileHandle) ReadAt(b []byte, offset int64) (n int, err error) {
return -1, ErrNotImplemented
}
// Seek wraps syscall.Seek.
func (f unixFileHandle) Seek(offset int64, whence int) (int64, error) {
newoffset, err := syscall.Seek(syscallFd(f), offset, whence)
return newoffset, handleSyscallError(err)
}
// isWindowsNulName reports whether name is os.DevNull ('NUL') on Windows.
// True is returned if name is 'NUL' whatever the case.
func isWindowsNulName(name string) bool {
if len(name) != 3 {
return false
}
if name[0] != 'n' && name[0] != 'N' {
return false
}
if name[1] != 'u' && name[1] != 'U' {
return false
}
if name[2] != 'l' && name[2] != 'L' {
return false
}
return true
}