libgo/go/os/types_windows.go

   1 // Copyright 2009 The Go Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style
   3 // license that can be found in the LICENSE file.
   4
   5 package os
   6
   7 import (
   8         "sync"
   9         "syscall"
  10         "time"
  11 )
  12
  13 // A fileStat is the implementation of FileInfo returned by Stat and Lstat.
  14 type fileStat struct {
  15         name string
  16         sys  syscall.Win32FileAttributeData
  17         pipe bool
  18
  19         // used to implement SameFile
  20         sync.Mutex
  21         path  string
  22         vol   uint32
  23         idxhi uint32
  24         idxlo uint32
  25 }
  26
  27 func (fs *fileStat) Size() int64 {
  28         return int64(fs.sys.FileSizeHigh)<<32 + int64(fs.sys.FileSizeLow)
  29 }
  30
  31 func (fs *fileStat) Mode() (m FileMode) {
  32         if fs == &devNullStat {
  33                 return ModeDevice | ModeCharDevice | 0666
  34         }
  35         if fs.sys.FileAttributes&syscall.FILE_ATTRIBUTE_DIRECTORY != 0 {
  36                 m |= ModeDir | 0111
  37         }
  38         if fs.sys.FileAttributes&syscall.FILE_ATTRIBUTE_READONLY != 0 {
  39                 m |= 0444
  40         } else {
  41                 m |= 0666
  42         }
  43         if fs.sys.FileAttributes&syscall.FILE_ATTRIBUTE_REPARSE_POINT != 0 {
  44                 m |= ModeSymlink
  45         }
  46         if fs.pipe {
  47                 m |= ModeNamedPipe
  48         }
  49         return m
  50 }
  51
  52 func (fs *fileStat) ModTime() time.Time {
  53         return time.Unix(0, fs.sys.LastWriteTime.Nanoseconds())
  54 }
  55
  56 // Sys returns syscall.Win32FileAttributeData for file fs.
  57 func (fs *fileStat) Sys() interface{} { return &fs.sys }
  58
  59 func (fs *fileStat) loadFileId() error {
  60         fs.Lock()
  61         defer fs.Unlock()
  62         if fs.path == "" {
  63                 // already done
  64                 return nil
  65         }
  66         pathp, err := syscall.UTF16PtrFromString(fs.path)
  67         if err != nil {
  68                 return err
  69         }
  70         h, err := syscall.CreateFile(pathp, 0, 0, nil, syscall.OPEN_EXISTING, syscall.FILE_FLAG_BACKUP_SEMANTICS, 0)
  71         if err != nil {
  72                 return err
  73         }
  74         defer syscall.CloseHandle(h)
  75         var i syscall.ByHandleFileInformation
  76         err = syscall.GetFileInformationByHandle(h, &i)
  77         if err != nil {
  78                 return err
  79         }
  80         fs.path = ""
  81         fs.vol = i.VolumeSerialNumber
  82         fs.idxhi = i.FileIndexHigh
  83         fs.idxlo = i.FileIndexLow
  84         return nil
  85 }
  86
  87 // devNullStat is fileStat structure describing DevNull file ("NUL").
  88 var devNullStat = fileStat{
  89         name: DevNull,
  90         // hopefully this will work for SameFile
  91         vol:   0,
  92         idxhi: 0,
  93         idxlo: 0,
  94 }
  95
  96 func sameFile(fs1, fs2 *fileStat) bool {
  97         e := fs1.loadFileId()
  98         if e != nil {
  99                 return false
 100         }
 101         e = fs2.loadFileId()
 102         if e != nil {
 103                 return false
 104         }
 105         return fs1.vol == fs2.vol && fs1.idxhi == fs2.idxhi && fs1.idxlo == fs2.idxlo
 106 }
 107
 108 // For testing.
 109 func atime(fi FileInfo) time.Time {
 110         return time.Unix(0, fi.Sys().(*syscall.Win32FileAttributeData).LastAccessTime.Nanoseconds())
 111 }