github.com/goproxy0/go@v0.0.0-20171111080102-49cc0c489d2c/src/os/types_windows.go (about)

     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  	filetype uint32 // what syscall.GetFileType returns
    18  
    19  	// used to implement SameFile
    20  	sync.Mutex
    21  	path             string
    22  	vol              uint32
    23  	idxhi            uint32
    24  	idxlo            uint32
    25  	appendNameToPath bool
    26  }
    27  
    28  func (fs *fileStat) Size() int64 {
    29  	return int64(fs.sys.FileSizeHigh)<<32 + int64(fs.sys.FileSizeLow)
    30  }
    31  
    32  func (fs *fileStat) Mode() (m FileMode) {
    33  	if fs == &devNullStat {
    34  		return ModeDevice | ModeCharDevice | 0666
    35  	}
    36  	if fs.sys.FileAttributes&syscall.FILE_ATTRIBUTE_READONLY != 0 {
    37  		m |= 0444
    38  	} else {
    39  		m |= 0666
    40  	}
    41  	if fs.sys.FileAttributes&syscall.FILE_ATTRIBUTE_REPARSE_POINT != 0 {
    42  		return m | ModeSymlink
    43  	}
    44  	if fs.sys.FileAttributes&syscall.FILE_ATTRIBUTE_DIRECTORY != 0 {
    45  		m |= ModeDir | 0111
    46  	}
    47  	switch fs.filetype {
    48  	case syscall.FILE_TYPE_PIPE:
    49  		m |= ModeNamedPipe
    50  	case syscall.FILE_TYPE_CHAR:
    51  		m |= ModeCharDevice
    52  	}
    53  	return m
    54  }
    55  
    56  func (fs *fileStat) ModTime() time.Time {
    57  	return time.Unix(0, fs.sys.LastWriteTime.Nanoseconds())
    58  }
    59  
    60  // Sys returns syscall.Win32FileAttributeData for file fs.
    61  func (fs *fileStat) Sys() interface{} { return &fs.sys }
    62  
    63  func (fs *fileStat) loadFileId() error {
    64  	fs.Lock()
    65  	defer fs.Unlock()
    66  	if fs.path == "" {
    67  		// already done
    68  		return nil
    69  	}
    70  	var path string
    71  	if fs.appendNameToPath {
    72  		path = fs.path + `\` + fs.name
    73  	} else {
    74  		path = fs.path
    75  	}
    76  	pathp, err := syscall.UTF16PtrFromString(path)
    77  	if err != nil {
    78  		return err
    79  	}
    80  	h, err := syscall.CreateFile(pathp, 0, 0, nil, syscall.OPEN_EXISTING, syscall.FILE_FLAG_BACKUP_SEMANTICS, 0)
    81  	if err != nil {
    82  		return err
    83  	}
    84  	defer syscall.CloseHandle(h)
    85  	var i syscall.ByHandleFileInformation
    86  	err = syscall.GetFileInformationByHandle(h, &i)
    87  	if err != nil {
    88  		return err
    89  	}
    90  	fs.path = ""
    91  	fs.vol = i.VolumeSerialNumber
    92  	fs.idxhi = i.FileIndexHigh
    93  	fs.idxlo = i.FileIndexLow
    94  	return nil
    95  }
    96  
    97  // devNullStat is fileStat structure describing DevNull file ("NUL").
    98  var devNullStat = fileStat{
    99  	name: DevNull,
   100  	// hopefully this will work for SameFile
   101  	vol:   0,
   102  	idxhi: 0,
   103  	idxlo: 0,
   104  }
   105  
   106  func sameFile(fs1, fs2 *fileStat) bool {
   107  	e := fs1.loadFileId()
   108  	if e != nil {
   109  		return false
   110  	}
   111  	e = fs2.loadFileId()
   112  	if e != nil {
   113  		return false
   114  	}
   115  	return fs1.vol == fs2.vol && fs1.idxhi == fs2.idxhi && fs1.idxlo == fs2.idxlo
   116  }
   117  
   118  // For testing.
   119  func atime(fi FileInfo) time.Time {
   120  	return time.Unix(0, fi.Sys().(*syscall.Win32FileAttributeData).LastAccessTime.Nanoseconds())
   121  }