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
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
|
/* savedir.c -- save the list of files in a directory in a string
Copyright (C) 1990, 1997-2001, 2003-2006, 2009-2015 Free Software
Foundation, Inc.
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program 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 General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>. */
/* Written by David MacKenzie <djm@gnu.ai.mit.edu>. */
#include <config.h>
#include "savedir.h"
#include <sys/types.h>
#include <errno.h>
#include "dirent--.h"
#ifndef _D_EXACT_NAMLEN
# define _D_EXACT_NAMLEN(dp) strlen ((dp)->d_name)
#endif
#include <stddef.h>
#include <stdlib.h>
#include <string.h>
#include "xalloc.h"
typedef struct
{
char *name;
#if D_INO_IN_DIRENT
ino_t ino;
#endif
} direntry_t;
/* Compare the names of two directory entries */
static int
direntry_cmp_name (void const *a, void const *b)
{
direntry_t const *dea = a;
direntry_t const *deb = b;
return strcmp (dea->name, deb->name);
}
#if D_INO_IN_DIRENT
/* Compare the inode numbers of two directory entries */
static int
direntry_cmp_inode (void const *a, void const *b)
{
direntry_t const *dea = a;
direntry_t const *deb = b;
return dea->ino < deb->ino ? -1 : dea->ino > deb->ino;
}
#endif
typedef int (*comparison_function) (void const *, void const *);
static comparison_function const comparison_function_table[] =
{
0,
direntry_cmp_name
#if D_INO_IN_DIRENT
, direntry_cmp_inode
#endif
};
/* Return a freshly allocated string containing the file names
in directory DIRP, separated by '\0' characters;
the end is marked by two '\0' characters in a row.
Returned values are sorted according to OPTION.
Return NULL (setting errno) if DIRP cannot be read.
If DIRP is NULL, return NULL without affecting errno. */
char *
streamsavedir (DIR *dirp, enum savedir_option option)
{
char *name_space = NULL;
size_t allocated = 0;
direntry_t *entries = NULL;
size_t entries_allocated = 0;
size_t entries_used = 0;
size_t used = 0;
int readdir_errno;
comparison_function cmp = comparison_function_table[option];
if (dirp == NULL)
return NULL;
for (;;)
{
struct dirent const *dp;
char const *entry;
errno = 0;
dp = readdir (dirp);
if (! dp)
break;
/* Skip "", ".", and "..". "" is returned by at least one buggy
implementation: Solaris 2.4 readdir on NFS file systems. */
entry = dp->d_name;
if (entry[entry[0] != '.' ? 0 : entry[1] != '.' ? 1 : 2] != '\0')
{
size_t entry_size = _D_EXACT_NAMLEN (dp) + 1;
if (cmp)
{
if (entries_allocated == entries_used)
{
size_t n = entries_allocated;
entries = x2nrealloc (entries, &n, sizeof *entries);
entries_allocated = n;
}
entries[entries_used].name = xstrdup (entry);
#if D_INO_IN_DIRENT
entries[entries_used].ino = dp->d_ino;
#endif
entries_used++;
}
else
{
if (allocated - used <= entry_size)
{
size_t n = used + entry_size;
if (n < used)
xalloc_die ();
name_space = x2nrealloc (name_space, &n, 1);
allocated = n;
}
memcpy (name_space + used, entry, entry_size);
}
used += entry_size;
}
}
readdir_errno = errno;
if (readdir_errno != 0)
{
free (entries);
free (name_space);
errno = readdir_errno;
return NULL;
}
if (cmp)
{
size_t i;
if (entries_used)
qsort (entries, entries_used, sizeof *entries, cmp);
name_space = xmalloc (used + 1);
used = 0;
for (i = 0; i < entries_used; i++)
{
char *dest = name_space + used;
used += stpcpy (dest, entries[i].name) - dest + 1;
free (entries[i].name);
}
free (entries);
}
else if (used == allocated)
name_space = xrealloc (name_space, used + 1);
name_space[used] = '\0';
return name_space;
}
/* Return a freshly allocated string containing the file names
in directory DIR, separated by '\0' characters;
the end is marked by two '\0' characters in a row.
Return NULL (setting errno) if DIR cannot be opened, read, or closed. */
char *
savedir (char const *dir, enum savedir_option option)
{
DIR *dirp = opendir (dir);
if (! dirp)
return NULL;
else
{
char *name_space = streamsavedir (dirp, option);
if (closedir (dirp) != 0)
{
int closedir_errno = errno;
free (name_space);
errno = closedir_errno;
return NULL;
}
return name_space;
}
}
|
