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authorThomas Guyot-Sionnest <dermoth@aei.ca>2010-04-08 01:11:46 (GMT)
committerThomas Guyot-Sionnest <dermoth@aei.ca>2010-04-13 01:26:35 (GMT)
commit74da141e618ef99959d509cb2e7be35a348a39db (patch)
tree88ebc38b381a1021fc2d74864a71e230ae591c3d /gl/dup2.c
parentc63a4f726a0b6ad8cf6040f947754a81fd4683bb (diff)
downloadmonitoring-plugins-74da141e618ef99959d509cb2e7be35a348a39db.tar.gz
Sync with the latest Gnulib code (177f525)
Signed-off-by: Thomas Guyot-Sionnest <dermoth@aei.ca>
Diffstat (limited to 'gl/dup2.c')
-rw-r--r--gl/dup2.c128
1 files changed, 128 insertions, 0 deletions
diff --git a/gl/dup2.c b/gl/dup2.c
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1/* Duplicate an open file descriptor to a specified file descriptor.
2
3 Copyright (C) 1999, 2004-2007, 2009-2010 Free Software Foundation, Inc.
4
5 This program is free software: you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published by
7 the Free Software Foundation; either version 3 of the License, or
8 (at your option) any later version.
9
10 This program 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 General Public License for more details.
14
15 You should have received a copy of the GNU General Public License
16 along with this program. If not, see <http://www.gnu.org/licenses/>. */
17
18/* written by Paul Eggert */
19
20#include <config.h>
21
22/* Specification. */
23#include <unistd.h>
24
25#include <errno.h>
26#include <fcntl.h>
27
28#if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
29/* Get declarations of the Win32 API functions. */
30# define WIN32_LEAN_AND_MEAN
31# include <windows.h>
32#endif
33
34#if HAVE_DUP2
35
36# undef dup2
37
38int
39rpl_dup2 (int fd, int desired_fd)
40{
41 int result;
42# if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
43 /* If fd is closed, mingw hangs on dup2 (fd, fd). If fd is open,
44 dup2 (fd, fd) returns 0, but all further attempts to use fd in
45 future dup2 calls will hang. */
46 if (fd == desired_fd)
47 {
48 if ((HANDLE) _get_osfhandle (fd) == INVALID_HANDLE_VALUE)
49 {
50 errno = EBADF;
51 return -1;
52 }
53 return fd;
54 }
55 /* Wine 1.0.1 return 0 when desired_fd is negative but not -1:
56 http://bugs.winehq.org/show_bug.cgi?id=21289 */
57 if (desired_fd < 0)
58 {
59 errno = EBADF;
60 return -1;
61 }
62# endif
63 result = dup2 (fd, desired_fd);
64# ifdef __linux__
65 /* Correct a Linux return value.
66 <http://git.kernel.org/?p=linux/kernel/git/stable/linux-2.6.30.y.git;a=commitdiff;h=2b79bc4f7ebbd5af3c8b867968f9f15602d5f802>
67 */
68 if (fd == desired_fd && result == (unsigned int) -EBADF)
69 {
70 errno = EBADF;
71 result = -1;
72 }
73# endif
74 if (result == 0)
75 result = desired_fd;
76 /* Correct a cygwin 1.5.x errno value. */
77 else if (result == -1 && errno == EMFILE)
78 errno = EBADF;
79# if REPLACE_FCHDIR
80 if (fd != desired_fd && result != -1)
81 result = _gl_register_dup (fd, result);
82# endif
83 return result;
84}
85
86#else /* !HAVE_DUP2 */
87
88/* On older platforms, dup2 did not exist. */
89
90# ifndef F_DUPFD
91static int
92dupfd (int fd, int desired_fd)
93{
94 int duplicated_fd = dup (fd);
95 if (duplicated_fd < 0 || duplicated_fd == desired_fd)
96 return duplicated_fd;
97 else
98 {
99 int r = dupfd (fd, desired_fd);
100 int e = errno;
101 close (duplicated_fd);
102 errno = e;
103 return r;
104 }
105}
106# endif
107
108int
109dup2 (int fd, int desired_fd)
110{
111 int result = fcntl (fd, F_GETFL) < 0 ? -1 : fd;
112 if (result == -1 || fd == desired_fd)
113 return result;
114 close (desired_fd);
115# ifdef F_DUPFD
116 result = fcntl (fd, F_DUPFD, desired_fd);
117# if REPLACE_FCHDIR
118 if (0 <= result)
119 result = _gl_register_dup (fd, result);
120# endif
121# else
122 result = dupfd (fd, desired_fd);
123# endif
124 if (result == -1 && (errno == EMFILE || errno == EINVAL))
125 errno = EBADF;
126 return result;
127}
128#endif /* !HAVE_DUP2 */