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-rw-r--r--gl/open.c166
1 files changed, 0 insertions, 166 deletions
diff --git a/gl/open.c b/gl/open.c
deleted file mode 100644
index f612b802..00000000
--- a/gl/open.c
+++ /dev/null
@@ -1,166 +0,0 @@
1/* Open a descriptor to a file.
2 Copyright (C) 2007-2010 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 <http://www.gnu.org/licenses/>. */
16
17/* Written by Bruno Haible <bruno@clisp.org>, 2007. */
18
19#include <config.h>
20
21/* Get the original definition of open. It might be defined as a macro. */
22#define __need_system_fcntl_h
23#include <fcntl.h>
24#undef __need_system_fcntl_h
25#include <sys/types.h>
26
27static inline int
28orig_open (const char *filename, int flags, mode_t mode)
29{
30 return open (filename, flags, mode);
31}
32
33/* Specification. */
34#include <fcntl.h>
35
36#include <errno.h>
37#include <stdarg.h>
38#include <string.h>
39#include <sys/types.h>
40#include <sys/stat.h>
41#include <unistd.h>
42
43#ifndef REPLACE_OPEN_DIRECTORY
44# define REPLACE_OPEN_DIRECTORY 0
45#endif
46
47int
48open (const char *filename, int flags, ...)
49{
50 mode_t mode;
51 int fd;
52
53 mode = 0;
54 if (flags & O_CREAT)
55 {
56 va_list arg;
57 va_start (arg, flags);
58
59 /* We have to use PROMOTED_MODE_T instead of mode_t, otherwise GCC 4
60 creates crashing code when 'mode_t' is smaller than 'int'. */
61 mode = va_arg (arg, PROMOTED_MODE_T);
62
63 va_end (arg);
64 }
65
66#if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
67 if (strcmp (filename, "/dev/null") == 0)
68 filename = "NUL";
69#endif
70
71#if OPEN_TRAILING_SLASH_BUG
72 /* If the filename ends in a slash and one of O_CREAT, O_WRONLY, O_RDWR
73 is specified, then fail.
74 Rationale: POSIX <http://www.opengroup.org/susv3/basedefs/xbd_chap04.html>
75 says that
76 "A pathname that contains at least one non-slash character and that
77 ends with one or more trailing slashes shall be resolved as if a
78 single dot character ( '.' ) were appended to the pathname."
79 and
80 "The special filename dot shall refer to the directory specified by
81 its predecessor."
82 If the named file already exists as a directory, then
83 - if O_CREAT is specified, open() must fail because of the semantics
84 of O_CREAT,
85 - if O_WRONLY or O_RDWR is specified, open() must fail because POSIX
86 <http://www.opengroup.org/susv3/functions/open.html> says that it
87 fails with errno = EISDIR in this case.
88 If the named file does not exist or does not name a directory, then
89 - if O_CREAT is specified, open() must fail since open() cannot create
90 directories,
91 - if O_WRONLY or O_RDWR is specified, open() must fail because the
92 file does not contain a '.' directory. */
93 if (flags & (O_CREAT | O_WRONLY | O_RDWR))
94 {
95 size_t len = strlen (filename);
96 if (len > 0 && filename[len - 1] == '/')
97 {
98 errno = EISDIR;
99 return -1;
100 }
101 }
102#endif
103
104 fd = orig_open (filename, flags, mode);
105
106#if REPLACE_FCHDIR
107 /* Implementing fchdir and fdopendir requires the ability to open a
108 directory file descriptor. If open doesn't support that (as on
109 mingw), we use a dummy file that behaves the same as directories
110 on Linux (ie. always reports EOF on attempts to read()), and
111 override fstat() in fchdir.c to hide the fact that we have a
112 dummy. */
113 if (REPLACE_OPEN_DIRECTORY && fd < 0 && errno == EACCES
114 && (flags & O_ACCMODE) == O_RDONLY)
115 {
116 struct stat statbuf;
117 if (stat (filename, &statbuf) == 0 && S_ISDIR (statbuf.st_mode))
118 {
119 /* Maximum recursion depth of 1. */
120 fd = open ("/dev/null", flags, mode);
121 if (0 <= fd)
122 fd = _gl_register_fd (fd, filename);
123 }
124 else
125 errno = EACCES;
126 }
127#endif
128
129#if OPEN_TRAILING_SLASH_BUG
130 /* If the filename ends in a slash and fd does not refer to a directory,
131 then fail.
132 Rationale: POSIX <http://www.opengroup.org/susv3/basedefs/xbd_chap04.html>
133 says that
134 "A pathname that contains at least one non-slash character and that
135 ends with one or more trailing slashes shall be resolved as if a
136 single dot character ( '.' ) were appended to the pathname."
137 and
138 "The special filename dot shall refer to the directory specified by
139 its predecessor."
140 If the named file without the slash is not a directory, open() must fail
141 with ENOTDIR. */
142 if (fd >= 0)
143 {
144 /* We know len is positive, since open did not fail with ENOENT. */
145 size_t len = strlen (filename);
146 if (filename[len - 1] == '/')
147 {
148 struct stat statbuf;
149
150 if (fstat (fd, &statbuf) >= 0 && !S_ISDIR (statbuf.st_mode))
151 {
152 close (fd);
153 errno = ENOTDIR;
154 return -1;
155 }
156 }
157 }
158#endif
159
160#if REPLACE_FCHDIR
161 if (!REPLACE_OPEN_DIRECTORY && 0 <= fd)
162 fd = _gl_register_fd (fd, filename);
163#endif
164
165 return fd;
166}