1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
|
/* Duplicate an open file descriptor to a specified file descriptor.
Copyright (C) 1999, 2004-2007, 2009-2016 Free Software Foundation, Inc.
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>. */
/* written by Paul Eggert */
#include <config.h>
/* Specification. */
#include <unistd.h>
#include <errno.h>
#include <fcntl.h>
#if HAVE_DUP2
# undef dup2
# if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
/* Get declarations of the native Windows API functions. */
# define WIN32_LEAN_AND_MEAN
# include <windows.h>
# include "msvc-inval.h"
/* Get _get_osfhandle. */
# include "msvc-nothrow.h"
static int
ms_windows_dup2 (int fd, int desired_fd)
{
int result;
/* If fd is closed, mingw hangs on dup2 (fd, fd). If fd is open,
dup2 (fd, fd) returns 0, but all further attempts to use fd in
future dup2 calls will hang. */
if (fd == desired_fd)
{
if ((HANDLE) _get_osfhandle (fd) == INVALID_HANDLE_VALUE)
{
errno = EBADF;
return -1;
}
return fd;
}
/* Wine 1.0.1 return 0 when desired_fd is negative but not -1:
http://bugs.winehq.org/show_bug.cgi?id=21289 */
if (desired_fd < 0)
{
errno = EBADF;
return -1;
}
TRY_MSVC_INVAL
{
result = dup2 (fd, desired_fd);
}
CATCH_MSVC_INVAL
{
errno = EBADF;
result = -1;
}
DONE_MSVC_INVAL;
if (result == 0)
result = desired_fd;
return result;
}
# define dup2 ms_windows_dup2
# elif defined __KLIBC__
# include <InnoTekLIBC/backend.h>
static int
klibc_dup2dirfd (int fd, int desired_fd)
{
int tempfd;
int dupfd;
tempfd = open ("NUL", O_RDONLY);
if (tempfd == -1)
return -1;
if (tempfd == desired_fd)
{
close (tempfd);
char path[_MAX_PATH];
if (__libc_Back_ioFHToPath (fd, path, sizeof (path)))
return -1;
return open(path, O_RDONLY);
}
dupfd = klibc_dup2dirfd (fd, desired_fd);
close (tempfd);
return dupfd;
}
static int
klibc_dup2 (int fd, int desired_fd)
{
int dupfd;
struct stat sbuf;
dupfd = dup2 (fd, desired_fd);
if (dupfd == -1 && errno == ENOTSUP \
&& !fstat (fd, &sbuf) && S_ISDIR (sbuf.st_mode))
{
close (desired_fd);
return klibc_dup2dirfd (fd, desired_fd);
}
return dupfd;
}
# define dup2 klibc_dup2
# endif
int
rpl_dup2 (int fd, int desired_fd)
{
int result;
# ifdef F_GETFL
/* On Linux kernels 2.6.26-2.6.29, dup2 (fd, fd) returns -EBADF.
On Cygwin 1.5.x, dup2 (1, 1) returns 0.
On Cygwin 1.7.17, dup2 (1, -1) dumps core.
On Cygwin 1.7.25, dup2 (1, 256) can dump core.
On Haiku, dup2 (fd, fd) mistakenly clears FD_CLOEXEC. */
# if HAVE_SETDTABLESIZE
setdtablesize (desired_fd + 1);
# endif
if (desired_fd < 0)
fd = desired_fd;
if (fd == desired_fd)
return fcntl (fd, F_GETFL) == -1 ? -1 : fd;
# endif
result = dup2 (fd, desired_fd);
/* Correct an errno value on FreeBSD 6.1 and Cygwin 1.5.x. */
if (result == -1 && errno == EMFILE)
errno = EBADF;
# if REPLACE_FCHDIR
if (fd != desired_fd && result != -1)
result = _gl_register_dup (fd, result);
# endif
return result;
}
#else /* !HAVE_DUP2 */
/* On older platforms, dup2 did not exist. */
# ifndef F_DUPFD
static int
dupfd (int fd, int desired_fd)
{
int duplicated_fd = dup (fd);
if (duplicated_fd < 0 || duplicated_fd == desired_fd)
return duplicated_fd;
else
{
int r = dupfd (fd, desired_fd);
int e = errno;
close (duplicated_fd);
errno = e;
return r;
}
}
# endif
int
dup2 (int fd, int desired_fd)
{
int result = fcntl (fd, F_GETFL) < 0 ? -1 : fd;
if (result == -1 || fd == desired_fd)
return result;
close (desired_fd);
# ifdef F_DUPFD
result = fcntl (fd, F_DUPFD, desired_fd);
# if REPLACE_FCHDIR
if (0 <= result)
result = _gl_register_dup (fd, result);
# endif
# else
result = dupfd (fd, desired_fd);
# endif
if (result == -1 && (errno == EMFILE || errno == EINVAL))
errno = EBADF;
return result;
}
#endif /* !HAVE_DUP2 */
|
