1 | /* Copyright (C) 2005-2024 Free Software Foundation, Inc. |
2 | This file is part of the GNU C Library. |
3 | |
4 | The GNU C Library is free software; you can redistribute it and/or |
5 | modify it under the terms of the GNU Lesser General Public |
6 | License as published by the Free Software Foundation; either |
7 | version 2.1 of the License, or (at your option) any later version. |
8 | |
9 | The GNU C Library is distributed in the hope that it will be useful, |
10 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
11 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
12 | Lesser General Public License for more details. |
13 | |
14 | You should have received a copy of the GNU Lesser General Public |
15 | License along with the GNU C Library; if not, see |
16 | <https://www.gnu.org/licenses/>. */ |
17 | |
18 | #include <limits.h> |
19 | #include <stdlib.h> |
20 | #include <string.h> |
21 | #include <unistd.h> |
22 | #include <errno.h> |
23 | |
24 | |
25 | char * |
26 | __realpath_chk (const char *buf, char *resolved, size_t resolvedlen) |
27 | { |
28 | #ifdef PATH_MAX |
29 | if (resolvedlen < PATH_MAX) |
30 | __chk_fail (); |
31 | |
32 | return __realpath (buf, resolved); |
33 | #else |
34 | long int pathmax; |
35 | |
36 | if (buf == NULL) |
37 | { |
38 | __set_errno (EINVAL); |
39 | return NULL; |
40 | } |
41 | |
42 | pathmax = __pathconf (buf, _PC_PATH_MAX); |
43 | if (pathmax != -1) |
44 | { |
45 | /* We do have a fixed limit. */ |
46 | if (resolvedlen < pathmax) |
47 | __chk_fail (); |
48 | |
49 | return __realpath (buf, resolved); |
50 | } |
51 | |
52 | /* Since there is no fixed limit we check whether the size is large |
53 | enough. */ |
54 | char *res = __realpath (buf, NULL); |
55 | if (res != NULL) |
56 | { |
57 | size_t actlen = strlen (res) + 1; |
58 | if (actlen > resolvedlen) |
59 | __chk_fail (); |
60 | |
61 | memcpy (resolved, res, actlen); |
62 | free (res); |
63 | res = resolved; |
64 | } |
65 | |
66 | return res; |
67 | #endif |
68 | } |
69 | |