libgo/go/os/dir_plan9.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         "io"
   9         "syscall"
  10 )
  11
  12 func (file *File) readdir(n int) ([]FileInfo, error) {
  13         // If this file has no dirinfo, create one.
  14         if file.dirinfo == nil {
  15                 file.dirinfo = new(dirInfo)
  16         }
  17         d := file.dirinfo
  18         size := n
  19         if size <= 0 {
  20                 size = 100
  21                 n = -1
  22         }
  23         fi := make([]FileInfo, 0, size) // Empty with room to grow.
  24         for n != 0 {
  25                 // Refill the buffer if necessary.
  26                 if d.bufp >= d.nbuf {
  27                         nb, err := file.Read(d.buf[:])
  28
  29                         // Update the buffer state before checking for errors.
  30                         d.bufp, d.nbuf = 0, nb
  31
  32                         if err != nil {
  33                                 if err == io.EOF {
  34                                         break
  35                                 }
  36                                 return fi, &PathError{"readdir", file.name, err}
  37                         }
  38                         if nb < syscall.STATFIXLEN {
  39                                 return fi, &PathError{"readdir", file.name, syscall.ErrShortStat}
  40                         }
  41                 }
  42
  43                 // Get a record from the buffer.
  44                 b := d.buf[d.bufp:]
  45                 m := int(uint16(b[0])|uint16(b[1])<<8) + 2
  46                 if m < syscall.STATFIXLEN {
  47                         return fi, &PathError{"readdir", file.name, syscall.ErrShortStat}
  48                 }
  49
  50                 dir, err := syscall.UnmarshalDir(b[:m])
  51                 if err != nil {
  52                         return fi, &PathError{"readdir", file.name, err}
  53                 }
  54                 fi = append(fi, fileInfoFromStat(dir))
  55
  56                 d.bufp += m
  57                 n--
  58         }
  59
  60         if n >= 0 && len(fi) == 0 {
  61                 return fi, io.EOF
  62         }
  63         return fi, nil
  64 }
  65
  66 func (file *File) readdirnames(n int) (names []string, err error) {
  67         fi, err := file.Readdir(n)
  68         names = make([]string, len(fi))
  69         for i := range fi {
  70                 names[i] = fi[i].Name()
  71         }
  72         return
  73 }