1 /* Open a descriptor to a file.
2 Copyright (C) 2007-2009 Free Software Foundation, Inc.
4 This program is free software: you can redistribute it and/or modify
5 it under the terms of the GNU General Public License as published by
6 the Free Software Foundation; either version 3 of the License, or
7 (at your option) any later version.
9 This program 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
12 GNU General Public License for more details.
14 You should have received a copy of the GNU General Public License
15 along with this program. If not, see <http://www.gnu.org/licenses/>. */
17 /* Written by Bruno Haible <bruno@clisp.org>, 2007. */
21 /* Get the original definition of open. It might be defined as a macro. */
22 #define __need_system_fcntl_h
24 #undef __need_system_fcntl_h
25 #include <sys/types.h>
28 orig_open (const char *filename, int flags, mode_t mode)
30 return open (filename, flags, mode);
39 #include <sys/types.h>
43 open (const char *filename, int flags, ...)
52 va_start (arg, flags);
54 /* We have to use PROMOTED_MODE_T instead of mode_t, otherwise GCC 4
55 creates crashing code when 'mode_t' is smaller than 'int'. */
56 mode = va_arg (arg, PROMOTED_MODE_T);
61 #if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
62 if (strcmp (filename, "/dev/null") == 0)
66 #if OPEN_TRAILING_SLASH_BUG
67 /* If the filename ends in a slash and one of O_CREAT, O_WRONLY, O_RDWR
68 is specified, then fail.
69 Rationale: POSIX <http://www.opengroup.org/susv3/basedefs/xbd_chap04.html>
71 "A pathname that contains at least one non-slash character and that
72 ends with one or more trailing slashes shall be resolved as if a
73 single dot character ( '.' ) were appended to the pathname."
75 "The special filename dot shall refer to the directory specified by
77 If the named file already exists as a directory, then
78 - if O_CREAT is specified, open() must fail because of the semantics
80 - if O_WRONLY or O_RDWR is specified, open() must fail because POSIX
81 <http://www.opengroup.org/susv3/functions/open.html> says that it
82 fails with errno = EISDIR in this case.
83 If the named file does not exist or does not name a directory, then
84 - if O_CREAT is specified, open() must fail since open() cannot create
86 - if O_WRONLY or O_RDWR is specified, open() must fail because the
87 file does not contain a '.' directory. */
88 if (flags & (O_CREAT | O_WRONLY | O_RDWR))
90 size_t len = strlen (filename);
91 if (len > 0 && filename[len - 1] == '/')
99 fd = orig_open (filename, flags, mode);
101 #if OPEN_TRAILING_SLASH_BUG
102 /* If the filename ends in a slash and fd does not refer to a directory,
104 Rationale: POSIX <http://www.opengroup.org/susv3/basedefs/xbd_chap04.html>
106 "A pathname that contains at least one non-slash character and that
107 ends with one or more trailing slashes shall be resolved as if a
108 single dot character ( '.' ) were appended to the pathname."
110 "The special filename dot shall refer to the directory specified by
112 If the named file without the slash is not a directory, open() must fail
116 size_t len = strlen (filename);
117 if (len > 0 && filename[len - 1] == '/')
121 if (fstat (fd, &statbuf) >= 0 && !S_ISDIR (statbuf.st_mode))
131 #ifdef FCHDIR_REPLACEMENT
133 _gl_register_fd (fd, filename);