1 | /* Logic guts of scandir*. |
2 | Copyright (C) 1992-2017 Free Software Foundation, Inc. |
3 | This file is part of the GNU C Library. |
4 | |
5 | The GNU C Library is free software; you can redistribute it and/or |
6 | modify it under the terms of the GNU Lesser General Public |
7 | License as published by the Free Software Foundation; either |
8 | version 2.1 of the License, or (at your option) any later version. |
9 | |
10 | The GNU C Library is distributed in the hope that it will be useful, |
11 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
13 | Lesser General Public License for more details. |
14 | |
15 | You should have received a copy of the GNU Lesser General Public |
16 | License along with the GNU C Library; if not, see |
17 | <http://www.gnu.org/licenses/>. */ |
18 | |
19 | #include <dirent.h> |
20 | #include <errno.h> |
21 | #include <stdlib.h> |
22 | #include <string.h> |
23 | #include <libc-lock.h> |
24 | |
25 | #ifndef SCANDIR_TAIL |
26 | # define SCANDIR_TAIL __scandir_tail |
27 | # define READDIR __readdir |
28 | # define DIRENT_TYPE struct dirent |
29 | #endif |
30 | |
31 | internal_function |
32 | int |
33 | SCANDIR_TAIL (DIR *dp, |
34 | DIRENT_TYPE ***namelist, |
35 | int (*select) (const DIRENT_TYPE *), |
36 | int (*cmp) (const DIRENT_TYPE **, const DIRENT_TYPE **)) |
37 | { |
38 | if (dp == NULL) |
39 | return -1; |
40 | |
41 | int save = errno; |
42 | __set_errno (0); |
43 | |
44 | int result; |
45 | struct scandir_cancel_struct c = { .dp = dp }; |
46 | __libc_cleanup_push (&__scandir_cancel_handler, &c); |
47 | |
48 | DIRENT_TYPE **v = NULL; |
49 | size_t vsize = 0; |
50 | DIRENT_TYPE *d; |
51 | while ((d = READDIR (dp)) != NULL) |
52 | { |
53 | if (select != NULL) |
54 | { |
55 | int selected = (*select) (d); |
56 | |
57 | /* The SELECT function might have changed errno. It was |
58 | zero before and it need to be again to make the later |
59 | tests work. */ |
60 | __set_errno (0); |
61 | |
62 | if (!selected) |
63 | continue; |
64 | } |
65 | else |
66 | __set_errno (0); |
67 | |
68 | if (__glibc_unlikely (c.cnt == vsize)) |
69 | { |
70 | if (vsize == 0) |
71 | vsize = 10; |
72 | else |
73 | vsize *= 2; |
74 | DIRENT_TYPE **new = realloc (v, vsize * sizeof *v); |
75 | if (new == NULL) |
76 | break; |
77 | c.v = v = new; |
78 | } |
79 | |
80 | size_t dsize = &d->d_name[_D_ALLOC_NAMLEN (d)] - (char *) d; |
81 | DIRENT_TYPE *vnew = malloc (dsize); |
82 | if (vnew == NULL) |
83 | break; |
84 | v[c.cnt++] = (DIRENT_TYPE *) memcpy (vnew, d, dsize); |
85 | } |
86 | |
87 | if (__glibc_likely (errno == 0)) |
88 | { |
89 | __closedir (dp); |
90 | |
91 | /* Sort the list if we have a comparison function to sort with. */ |
92 | if (cmp != NULL) |
93 | qsort (v, c.cnt, sizeof *v, (__compar_fn_t) cmp); |
94 | |
95 | *namelist = v; |
96 | result = c.cnt; |
97 | } |
98 | else |
99 | { |
100 | /* This frees everything and calls closedir. */ |
101 | __scandir_cancel_handler (&c); |
102 | result = -1; |
103 | } |
104 | |
105 | __libc_cleanup_pop (0); |
106 | |
107 | if (result >= 0) |
108 | __set_errno (save); |
109 | return result; |
110 | } |
111 | |