1 /* Define PATH_MAX somehow. Requires sys/types.h.
2 Copyright (C) 1992, 1999, 2001, 2003, 2005, 2009-2023 Free Software
3 Foundation, Inc.
4
5 This file is free software: you can redistribute it and/or modify
6 it under the terms of the GNU Lesser General Public License as
7 published by the Free Software Foundation; either version 2.1 of the
8 License, or (at your option) any later version.
9
10 This file 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
13 GNU Lesser General Public License for more details.
14
15 You should have received a copy of the GNU Lesser General Public License
16 along with this program. If not, see <https://www.gnu.org/licenses/>. */
17
18 #ifndef _PATHMAX_H
19 # define _PATHMAX_H
20
21 /* POSIX:2008 defines PATH_MAX to be the maximum number of bytes in a filename,
22 including the terminating NUL byte.
23 <https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/limits.h.html>
24 PATH_MAX is not defined on systems which have no limit on filename length,
25 such as GNU/Hurd.
26
27 This file does *not* define PATH_MAX always. Programs that use this file
28 can handle the GNU/Hurd case in several ways:
29 - Either with a package-wide handling, or with a per-file handling,
30 - Either through a
31 #ifdef PATH_MAX
32 or through a fallback like
33 #ifndef PATH_MAX
34 # define PATH_MAX 8192
35 #endif
36 or through a fallback like
37 #ifndef PATH_MAX
38 # define PATH_MAX pathconf ("/", _PC_PATH_MAX)
39 #endif
40 */
41
42 # include <unistd.h>
43
44 # include <limits.h>
45
46 # ifndef _POSIX_PATH_MAX
47 # define _POSIX_PATH_MAX 256
48 # endif
49
50 /* Don't include sys/param.h if it already has been. */
51 # if defined HAVE_SYS_PARAM_H && !defined PATH_MAX && !defined MAXPATHLEN
52 # include <sys/param.h>
53 # endif
54
55 # if !defined PATH_MAX && defined MAXPATHLEN
56 # define PATH_MAX MAXPATHLEN
57 # endif
58
59 # ifdef __hpux
60 /* On HP-UX, PATH_MAX designates the maximum number of bytes in a filename,
61 *not* including the terminating NUL byte, and is set to 1023.
62 Additionally, when _XOPEN_SOURCE is defined to 500 or more, PATH_MAX is
63 not defined at all any more. */
64 # undef PATH_MAX
65 # define PATH_MAX 1024
66 # endif
67
68 # if defined _WIN32 && ! defined __CYGWIN__
69 /* The page "Naming Files, Paths, and Namespaces" on msdn.microsoft.com,
70 section "Maximum Path Length Limitation",
71 <https://docs.microsoft.com/en-us/windows/desktop/FileIO/naming-a-file#maximum-path-length-limitation>
72 explains that the maximum size of a filename, including the terminating
73 NUL byte, is 260 = 3 + 256 + 1.
74 This is the same value as
75 - FILENAME_MAX in <stdio.h>,
76 - _MAX_PATH in <stdlib.h>,
77 - MAX_PATH in <windef.h>.
78 Undefine the original value, because mingw's <limits.h> gets it wrong. */
79 # undef PATH_MAX
80 # define PATH_MAX 260
81 # endif
82
83 #endif /* _PATHMAX_H */