1 /* Create a file.
2 Copyright (C) 2007-2020 Free Software Foundation, Inc.
3
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.
8
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.
13
14 You should have received a copy of the GNU General Public License
15 along with this program. If not, see <https://www.gnu.org/licenses/>. */
16
17 /* If the user's config.h happens to include <fcntl.h>, let it include only
18 the system's <fcntl.h> here, so that orig_creat doesn't recurse to
19 rpl_creat. */
20 #define __need_system_fcntl_h
21 #include <config.h>
22
23 /* Get the original definition of creat. It might be defined as a macro. */
24 #include <fcntl.h>
25 #include <sys/types.h>
26 #undef __need_system_fcntl_h
27
28 static int
orig_creat(const char * filename,mode_t mode)29 orig_creat (const char *filename, mode_t mode)
30 {
31 return creat (filename, mode);
32 }
33
34 /* Specification. */
35 /* Write "fcntl.h" here, not <fcntl.h>, otherwise OSF/1 5.1 DTK cc eliminates
36 this include because of the preliminary #include <fcntl.h> above. */
37 #include "fcntl.h"
38
39 #include <errno.h>
40 #include <string.h>
41 #include <sys/types.h>
42
43 int
creat(const char * filename,mode_t mode)44 creat (const char *filename, mode_t mode)
45 {
46 #if OPEN_TRAILING_SLASH_BUG
47 /* Fail if the filename ends in a slash,
48 as POSIX says such a filename must name a directory
49 <https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap04.html#tag_04_13>:
50 "A pathname that contains at least one non-<slash> character and that
51 ends with one or more trailing <slash> characters shall not be resolved
52 successfully unless the last pathname component before the trailing
53 <slash> characters names an existing directory"
54 creat() is defined as being equivalent to open() with flags
55 O_CREAT | O_TRUNC | O_WRONLY. Therefore:
56 If the named file already exists as a directory, then creat() must fail
57 with errno = EISDIR.
58 If the named file does not exist or does not name a directory, then
59 creat() must fail since creat() cannot create directories. */
60 {
61 size_t len = strlen (filename);
62 if (len > 0 && filename[len - 1] == '/')
63 {
64 errno = EISDIR;
65 return -1;
66 }
67 }
68 #endif
69
70 #if defined _WIN32 && !defined __CYGWIN__
71 /* Remap the 'x' bits to the 'r' bits. */
72 mode = (mode & ~0111) | ((mode & 0111) << 2);
73 #endif
74
75 return orig_creat (filename, mode);
76 }
77