1 // Copyright 2011 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 "syscall" 9 "time" 10 ) 11 12 const _BIT16SZ = 2 13 14 func fileInfoFromStat(d *syscall.Dir) FileInfo { 15 fs := &fileStat{ 16 name: d.Name, 17 size: d.Length, 18 modTime: time.Unix(int64(d.Mtime), 0), 19 sys: d, 20 } 21 fs.mode = FileMode(d.Mode & 0777) 22 if d.Mode&syscall.DMDIR != 0 { 23 fs.mode |= ModeDir 24 } 25 if d.Mode&syscall.DMAPPEND != 0 { 26 fs.mode |= ModeAppend 27 } 28 if d.Mode&syscall.DMEXCL != 0 { 29 fs.mode |= ModeExclusive 30 } 31 if d.Mode&syscall.DMTMP != 0 { 32 fs.mode |= ModeTemporary 33 } 34 // Consider all files not served by #M as device files. 35 if d.Type != 'M' { 36 fs.mode |= ModeDevice 37 } 38 return fs 39 } 40 41 // arg is an open *File or a path string. 42 func dirstat(arg interface{}) (*syscall.Dir, error) { 43 var name string 44 var err error 45 46 size := syscall.STATFIXLEN + 16*4 47 48 for i := 0; i < 2; i++ { 49 buf := make([]byte, _BIT16SZ+size) 50 51 var n int 52 switch a := arg.(type) { 53 case *File: 54 name = a.name 55 n, err = syscall.Fstat(a.fd, buf) 56 case string: 57 name = a 58 n, err = syscall.Stat(a, buf) 59 default: 60 panic("phase error in dirstat") 61 } 62 63 if n < _BIT16SZ { 64 return nil, &PathError{"stat", name, err} 65 } 66 67 // Pull the real size out of the stat message. 68 size = int(uint16(buf[0]) | uint16(buf[1])<<8) 69 70 // If the stat message is larger than our buffer we will 71 // go around the loop and allocate one that is big enough. 72 if size <= n { 73 d, err := syscall.UnmarshalDir(buf[:n]) 74 if err != nil { 75 return nil, &PathError{"stat", name, err} 76 } 77 return d, nil 78 } 79 80 } 81 82 if err == nil { 83 err = syscall.ErrBadStat 84 } 85 86 return nil, &PathError{"stat", name, err} 87 } 88 89 // statNolog implements Stat for Plan 9. 90 func statNolog(name string) (FileInfo, error) { 91 d, err := dirstat(name) 92 if err != nil { 93 return nil, err 94 } 95 return fileInfoFromStat(d), nil 96 } 97 98 // lstatNolog implements Lstat for Plan 9. 99 func lstatNolog(name string) (FileInfo, error) { 100 return statNolog(name) 101 } 102 103 // For testing. 104 func atime(fi FileInfo) time.Time { 105 return time.Unix(int64(fi.Sys().(*syscall.Dir).Atime), 0) 106 } 107
