1 files changed, 317 insertions, 0 deletions
diff --git a/src/pkg/os/file_windows.go b/src/pkg/os/file_windows.go
new file mode 100644
index 000000000..70dd6e241
--- /dev/null
+++ b/src/pkg/os/file_windows.go
@@ -0,0 +1,317 @@
+// 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 (
+	"runtime"
+	"sync"
+	"syscall"
+)
+
+// File represents an open file descriptor.
+type File struct {
+	fd      syscall.Handle
+	name    string
+	dirinfo *dirInfo   // nil unless directory being read
+	nepipe  int        // number of consecutive EPIPE in Write
+	l       sync.Mutex // used to implement windows pread/pwrite
+}
+
+// Fd returns the Windows handle referencing the open file.
+func (file *File) Fd() syscall.Handle {
+	if file == nil {
+		return syscall.InvalidHandle
+	}
+	return file.fd
+}
+
+// NewFile returns a new File with the given file descriptor and name.
+func NewFile(fd syscall.Handle, name string) *File {
+	if fd < 0 {
+		return nil
+	}
+	f := &File{fd: fd, name: name}
+	runtime.SetFinalizer(f, (*File).Close)
+	return f
+}
+
+// Auxiliary information if the File describes a directory
+type dirInfo struct {
+	stat         syscall.Stat_t
+	usefirststat bool
+}
+
+const DevNull = "NUL"
+
+func (file *File) isdir() bool { return file != nil && file.dirinfo != nil }
+
+func openFile(name string, flag int, perm uint32) (file *File, err Error) {
+	r, e := syscall.Open(name, flag|syscall.O_CLOEXEC, perm)
+	if e != 0 {
+		return nil, &PathError{"open", name, Errno(e)}
+	}
+
+	// There's a race here with fork/exec, which we are
+	// content to live with.  See ../syscall/exec.go
+	if syscall.O_CLOEXEC == 0 { // O_CLOEXEC not supported
+		syscall.CloseOnExec(r)
+	}
+
+	return NewFile(r, name), nil
+}
+
+func openDir(name string) (file *File, err Error) {
+	d := new(dirInfo)
+	r, e := syscall.FindFirstFile(syscall.StringToUTF16Ptr(name+"\\*"), &d.stat.Windata)
+	if e != 0 {
+		return nil, &PathError{"open", name, Errno(e)}
+	}
+	f := NewFile(r, name)
+	d.usefirststat = true
+	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.
+// It returns the File and an Error, if any.
+func OpenFile(name string, flag int, perm uint32) (file *File, err Error) {
+	// TODO(brainman): not sure about my logic of assuming it is dir first, then fall back to file
+	r, e := openDir(name)
+	if e == nil {
+		if flag&O_WRONLY != 0 || flag&O_RDWR != 0 {
+			r.Close()
+			return nil, &PathError{"open", name, EISDIR}
+		}
+		return r, nil
+	}
+	r, e = openFile(name, flag, perm)
+	if e == nil {
+		return r, nil
+	}
+	// Imitating Unix behavior by replacing syscall.ERROR_PATH_NOT_FOUND with
+	// os.ENOTDIR. Not sure if we should go into that.
+	if e2, ok := e.(*PathError); ok {
+		if e3, ok := e2.Error.(Errno); ok {
+			if e3 == Errno(syscall.ERROR_PATH_NOT_FOUND) {
+				return nil, &PathError{"open", name, ENOTDIR}
+			}
+		}
+	}
+	return nil, e
+}
+
+// Close closes the File, rendering it unusable for I/O.
+// It returns an Error, if any.
+func (file *File) Close() Error {
+	if file == nil || file.fd < 0 {
+		return EINVAL
+	}
+	var e int
+	if file.isdir() {
+		e = syscall.FindClose(syscall.Handle(file.fd))
+	} else {
+		e = syscall.CloseHandle(syscall.Handle(file.fd))
+	}
+	var err Error
+	if e != 0 {
+		err = &PathError{"close", file.name, Errno(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) statFile(name string) (fi *FileInfo, err Error) {
+	var stat syscall.ByHandleFileInformation
+	e := syscall.GetFileInformationByHandle(syscall.Handle(file.fd), &stat)
+	if e != 0 {
+		return nil, &PathError{"stat", file.name, Errno(e)}
+	}
+	return fileInfoFromByHandleInfo(new(FileInfo), file.name, &stat), nil
+}
+
+// Stat returns the FileInfo structure describing file.
+// It returns the FileInfo and an error, if any.
+func (file *File) Stat() (fi *FileInfo, err Error) {
+	if file == nil || file.fd < 0 {
+		return nil, EINVAL
+	}
+	if file.isdir() {
+		// I don't know any better way to do that for directory
+		return Stat(file.name)
+	}
+	return file.statFile(file.name)
+}
+
+// Readdir reads the contents of the directory associated with file and
+// returns an array of up to n FileInfo structures, as would be returned
+// by Lstat, in directory order. Subsequent calls on the same file will yield
+// further FileInfos.
+//
+// If n > 0, Readdir returns at most n FileInfo structures. In this case, if
+// Readdir returns an empty slice, it will return a non-nil error
+// explaining why. At the end of a directory, the error is os.EOF.
+//
+// If n <= 0, Readdir returns all the FileInfo from the directory in
+// a single slice. In this case, if Readdir succeeds (reads all
+// the way to the end of the directory), it returns the slice and a
+// nil os.Error. If it encounters an error before the end of the
+// directory, Readdir returns the FileInfo read until that point
+// and a non-nil error.
+func (file *File) Readdir(n int) (fi []FileInfo, err Error) {
+	if file == nil || file.fd < 0 {
+		return nil, EINVAL
+	}
+	if !file.isdir() {
+		return nil, &PathError{"Readdir", file.name, ENOTDIR}
+	}
+	di := file.dirinfo
+	wantAll := n <= 0
+	size := n
+	if wantAll {
+		n = -1
+		size = 100
+	}
+	fi = make([]FileInfo, 0, size) // Empty with room to grow.
+	for n != 0 {
+		if di.usefirststat {
+			di.usefirststat = false
+		} else {
+			e := syscall.FindNextFile(syscall.Handle(file.fd), &di.stat.Windata)
+			if e != 0 {
+				if e == syscall.ERROR_NO_MORE_FILES {
+					break
+				} else {
+					err = &PathError{"FindNextFile", file.name, Errno(e)}
+					if !wantAll {
+						fi = nil
+					}
+					return
+				}
+			}
+		}
+		var f FileInfo
+		fileInfoFromWin32finddata(&f, &di.stat.Windata)
+		if f.Name == "." || f.Name == ".." { // Useless names
+			continue
+		}
+		n--
+		fi = append(fi, f)
+	}
+	if !wantAll && len(fi) == 0 {
+		return fi, EOF
+	}
+	return fi, 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 int) {
+	f.l.Lock()
+	defer f.l.Unlock()
+	return 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 int) {
+	f.l.Lock()
+	defer f.l.Unlock()
+	curoffset, e := syscall.Seek(f.fd, 0, 1)
+	if e != 0 {
+		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 != 0 {
+		return 0, e
+	}
+	return int(done), 0
+}
+
+// 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 int) {
+	f.l.Lock()
+	defer f.l.Unlock()
+	return 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 int) {
+	f.l.Lock()
+	defer f.l.Unlock()
+	curoffset, e := syscall.Seek(f.fd, 0, 1)
+	if e != 0 {
+		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 != 0 {
+		return 0, e
+	}
+	return int(done), 0
+}
+
+// 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 int) {
+	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
+}
+
+// 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 iserror(e) {
+		syscall.ForkLock.RUnlock()
+		return nil, nil, NewSyscallError("pipe", e)
+	}
+	syscall.CloseOnExec(p[0])
+	syscall.CloseOnExec(p[1])
+	syscall.ForkLock.RUnlock()
+
+	return NewFile(p[0], "|0"), NewFile(p[1], "|1"), nil
+}