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
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
|
/* Copyright (C) 1991-2019 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
#include <errno.h>
#include <limits.h>
#include <stddef.h>
#include <string.h>
#include <dirent.h>
#include <unistd.h>
#include <sys/types.h>
#include <assert.h>
#include <dirstream.h>
#ifndef __READDIR_R
# define __READDIR_R __readdir_r
# define __GETDENTS __getdents
# define DIRENT_TYPE struct dirent
# define __READDIR_R_ALIAS
#endif
/* Read a directory entry from DIRP. */
int
__READDIR_R (DIR *dirp, DIRENT_TYPE *entry, DIRENT_TYPE **result)
{
DIRENT_TYPE *dp;
size_t reclen;
const int saved_errno = errno;
int ret;
__libc_lock_lock (dirp->lock);
do
{
if (dirp->offset >= dirp->size)
{
/* We've emptied out our buffer. Refill it. */
size_t maxread;
ssize_t bytes;
#ifndef _DIRENT_HAVE_D_RECLEN
/* Fixed-size struct; must read one at a time (see below). */
maxread = sizeof *dp;
#else
maxread = dirp->allocation;
#endif
bytes = __GETDENTS (dirp->fd, dirp->data, maxread);
if (bytes <= 0)
{
/* On some systems getdents fails with ENOENT when the
open directory has been rmdir'd already. POSIX.1
requires that we treat this condition like normal EOF. */
if (bytes < 0 && errno == ENOENT)
{
bytes = 0;
__set_errno (saved_errno);
}
if (bytes < 0)
dirp->errcode = errno;
dp = NULL;
break;
}
dirp->size = (size_t) bytes;
/* Reset the offset into the buffer. */
dirp->offset = 0;
}
dp = (DIRENT_TYPE *) &dirp->data[dirp->offset];
#ifdef _DIRENT_HAVE_D_RECLEN
reclen = dp->d_reclen;
#else
/* The only version of `struct dirent*' that lacks `d_reclen'
is fixed-size. */
assert (sizeof dp->d_name > 1);
reclen = sizeof *dp;
/* The name is not terminated if it is the largest possible size.
Clobber the following byte to ensure proper null termination. We
read just one entry at a time above so we know that byte will not
be used later. */
dp->d_name[sizeof dp->d_name] = '\0';
#endif
dirp->offset += reclen;
#ifdef _DIRENT_HAVE_D_OFF
dirp->filepos = dp->d_off;
#else
dirp->filepos += reclen;
#endif
#ifdef NAME_MAX
if (reclen > offsetof (DIRENT_TYPE, d_name) + NAME_MAX + 1)
{
/* The record is very long. It could still fit into the
caller-supplied buffer if we can skip padding at the
end. */
size_t namelen = _D_EXACT_NAMLEN (dp);
if (namelen <= NAME_MAX)
reclen = offsetof (DIRENT_TYPE, d_name) + namelen + 1;
else
{
/* The name is too long. Ignore this file. */
dirp->errcode = ENAMETOOLONG;
dp->d_ino = 0;
continue;
}
}
#endif
/* Skip deleted and ignored files. */
}
while (dp->d_ino == 0);
if (dp != NULL)
{
*result = memcpy (entry, dp, reclen);
#ifdef _DIRENT_HAVE_D_RECLEN
entry->d_reclen = reclen;
#endif
ret = 0;
}
else
{
*result = NULL;
ret = dirp->errcode;
}
__libc_lock_unlock (dirp->lock);
return ret;
}
#ifdef __READDIR_R_ALIAS
weak_alias (__readdir_r, readdir_r)
#endif
#undef __READDIR_R
#undef __GETDENTS
#undef DIRENT_TYPE
#undef __READDIR_R_ALIAS
|
