1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
|
// 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 (
"io"
"sync/atomic"
"syscall"
"unsafe"
)
//extern opendir
func libc_opendir(*byte) *syscall.DIR
//extern closedir
func libc_closedir(*syscall.DIR) int
// FIXME: pathconf returns long, not int.
//extern pathconf
func libc_pathconf(*byte, int) int
func clen(n []byte) int {
for i := 0; i < len(n); i++ {
if n[i] == 0 {
return i
}
}
return len(n)
}
var nameMax int32
func (file *File) readdirnames(n int) (names []string, err error) {
if file.dirinfo == nil {
p, err := syscall.BytePtrFromString(file.name)
if err != nil {
return nil, err
}
elen := int(atomic.LoadInt32(&nameMax))
if elen == 0 {
syscall.Entersyscall()
plen := libc_pathconf(p, syscall.PC_NAME_MAX)
syscall.Exitsyscall()
if plen < 1024 {
plen = 1024
}
var dummy syscall.Dirent
elen = int(unsafe.Offsetof(dummy.Name)) + plen + 1
atomic.StoreInt32(&nameMax, int32(elen))
}
syscall.Entersyscall()
r := libc_opendir(p)
errno := syscall.GetErrno()
syscall.Exitsyscall()
if r == nil {
return nil, &PathError{"opendir", file.name, errno}
}
file.dirinfo = new(dirInfo)
file.dirinfo.buf = make([]byte, elen)
file.dirinfo.dir = r
}
entryDirent := (*syscall.Dirent)(unsafe.Pointer(&file.dirinfo.buf[0]))
size := n
if size <= 0 {
size = 100
n = -1
}
names = make([]string, 0, size) // Empty with room to grow.
for n != 0 {
var dirent *syscall.Dirent
pr := &dirent
syscall.Entersyscall()
i := libc_readdir_r(file.dirinfo.dir, entryDirent, pr)
syscall.Exitsyscall()
if i != 0 {
return names, NewSyscallError("readdir_r", i)
}
if dirent == nil {
break // EOF
}
bytes := (*[10000]byte)(unsafe.Pointer(&dirent.Name[0]))
var name = string(bytes[0:clen(bytes[:])])
if name == "." || name == ".." { // Useless names
continue
}
names = append(names, name)
n--
}
if n >= 0 && len(names) == 0 {
return names, io.EOF
}
return names, nil
}
|
