1 /* -*- buffer-read-only: t -*- vi: set ro: */
2 /* DO NOT EDIT! GENERATED AUTOMATICALLY! */
3 /* Provide file descriptor control.
5 Copyright (C) 2009, 2010 Free Software Foundation, Inc.
7 This program is free software: you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 3 of the License, or
10 (at your option) any later version.
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with this program. If not, see <http://www.gnu.org/licenses/>. */
20 /* Written by Eric Blake <ebb9@byu.net>. */
33 # define rpl_fcntl fcntl
37 #if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
38 /* Get declarations of the Win32 API functions. */
39 # define WIN32_LEAN_AND_MEAN
42 /* Upper bound on getdtablesize(). See lib/getdtablesize.c. */
43 # define OPEN_MAX_MAX 0x10000
45 /* Duplicate OLDFD into the first available slot of at least NEWFD,
46 which must be positive, with FLAGS determining whether the duplicate
47 will be inheritable. */
49 dupfd (int oldfd, int newfd, int flags)
51 /* Mingw has no way to create an arbitrary fd. Iterate until all
52 file descriptors less than newfd are filled up. */
53 HANDLE curr_process = GetCurrentProcess ();
54 HANDLE old_handle = (HANDLE) _get_osfhandle (oldfd);
55 unsigned char fds_to_close[OPEN_MAX_MAX / CHAR_BIT];
56 unsigned int fds_to_close_bound = 0;
58 BOOL inherit = flags & O_CLOEXEC ? FALSE : TRUE;
61 if (newfd < 0 || getdtablesize () <= newfd)
66 if (old_handle == INVALID_HANDLE_VALUE
67 || (mode = setmode (oldfd, O_BINARY)) == -1)
69 /* oldfd is not open, or is an unassigned standard file
74 setmode (oldfd, mode);
83 if (!DuplicateHandle (curr_process, /* SourceProcessHandle */
84 old_handle, /* SourceHandle */
85 curr_process, /* TargetProcessHandle */
86 (PHANDLE) &new_handle, /* TargetHandle */
87 (DWORD) 0, /* DesiredAccess */
88 inherit, /* InheritHandle */
89 DUPLICATE_SAME_ACCESS)) /* Options */
91 /* TODO: Translate GetLastError () into errno. */
96 duplicated_fd = _open_osfhandle ((long) new_handle, flags);
97 if (duplicated_fd < 0)
99 CloseHandle (new_handle);
104 if (newfd <= duplicated_fd)
106 result = duplicated_fd;
110 /* Set the bit duplicated_fd in fds_to_close[]. */
111 index = (unsigned int) duplicated_fd / CHAR_BIT;
112 if (fds_to_close_bound <= index)
114 if (sizeof fds_to_close <= index)
115 /* Need to increase OPEN_MAX_MAX. */
117 memset (fds_to_close + fds_to_close_bound, '\0',
118 index + 1 - fds_to_close_bound);
119 fds_to_close_bound = index + 1;
121 fds_to_close[index] |= 1 << ((unsigned int) duplicated_fd % CHAR_BIT);
124 /* Close the previous fds that turned out to be too small. */
126 int saved_errno = errno;
127 unsigned int duplicated_fd;
129 for (duplicated_fd = 0;
130 duplicated_fd < fds_to_close_bound * CHAR_BIT;
132 if ((fds_to_close[duplicated_fd / CHAR_BIT]
133 >> (duplicated_fd % CHAR_BIT))
135 close (duplicated_fd);
142 result = _gl_register_dup (oldfd, result);
148 /* Perform the specified ACTION on the file descriptor FD, possibly
149 using the argument ARG further described below. This replacement
150 handles the following actions, and forwards all others on to the
151 native fcntl. An unrecognized ACTION returns -1 with errno set to
154 F_DUPFD - duplicate FD, with int ARG being the minimum target fd.
155 If successful, return the duplicate, which will be inheritable;
156 otherwise return -1 and set errno.
158 F_DUPFD_CLOEXEC - duplicate FD, with int ARG being the minimum
159 target fd. If successful, return the duplicate, which will not be
160 inheritable; otherwise return -1 and set errno.
162 F_GETFD - ARG need not be present. If successful, return a
163 non-negative value containing the descriptor flags of FD (only
164 FD_CLOEXEC is portable, but other flags may be present); otherwise
165 return -1 and set errno. */
168 rpl_fcntl (int fd, int action, /* arg */...)
172 va_start (arg, action);
179 int target = va_arg (arg, int);
180 result = dupfd (fd, target, 0);
183 #elif FCNTL_DUPFD_BUGGY || REPLACE_FCHDIR
186 int target = va_arg (arg, int);
187 /* Detect invalid target; needed for cygwin 1.5.x. */
188 if (target < 0 || getdtablesize () <= target)
192 result = fcntl (fd, action, target);
195 result = _gl_register_dup (fd, result);
200 #endif /* FCNTL_DUPFD_BUGGY || REPLACE_FCHDIR */
202 case F_DUPFD_CLOEXEC:
204 int target = va_arg (arg, int);
207 result = dupfd (fd, target, O_CLOEXEC);
209 #else /* HAVE_FCNTL */
210 /* Try the system call first, if the headers claim it exists
211 (that is, if GNULIB_defined_F_DUPFD_CLOEXEC is 0), since we
212 may be running with a glibc that has the macro but with an
213 older kernel that does not support it. Cache the
214 information on whether the system call really works, but
215 avoid caching failure if the corresponding F_DUPFD fails
216 for any reason. 0 = unknown, 1 = yes, -1 = no. */
217 static int have_dupfd_cloexec = GNULIB_defined_F_DUPFD_CLOEXEC ? -1 : 0;
218 if (0 <= have_dupfd_cloexec)
220 result = fcntl (fd, action, target);
221 if (0 <= result || errno != EINVAL)
223 have_dupfd_cloexec = 1;
226 result = _gl_register_dup (fd, result);
231 result = rpl_fcntl (fd, F_DUPFD, target);
234 have_dupfd_cloexec = -1;
238 result = rpl_fcntl (fd, F_DUPFD, target);
239 if (0 <= result && have_dupfd_cloexec == -1)
241 int flags = fcntl (result, F_GETFD);
242 if (flags < 0 || fcntl (result, F_SETFD, flags | FD_CLOEXEC) == -1)
244 int saved_errno = errno;
251 #endif /* HAVE_FCNTL */
252 } /* F_DUPFD_CLOEXEC */
257 # if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
258 HANDLE handle = (HANDLE) _get_osfhandle (fd);
260 if (handle == INVALID_HANDLE_VALUE
261 || GetHandleInformation (handle, &flags) == 0)
264 result = (flags & HANDLE_FLAG_INHERIT) ? 0 : FD_CLOEXEC;
266 /* Use dup2 to reject invalid file descriptors. No way to
267 access this information, so punt. */
268 if (0 <= dup2 (fd, fd))
273 #endif /* !HAVE_FCNTL */
275 /* Implementing F_SETFD on mingw is not trivial - there is no
276 API for changing the O_NOINHERIT bit on an fd, and merely
277 changing the HANDLE_FLAG_INHERIT bit on the underlying handle
278 can lead to odd state. It may be possible by duplicating the
279 handle, using _open_osfhandle with the right flags, then
280 using dup2 to move the duplicate onto the original, but that
281 is not supported for now. */
286 void *p = va_arg (arg, void *);
287 result = fcntl (fd, action, p);