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-rw-r--r--gl/fcntl.c294
1 files changed, 0 insertions, 294 deletions
diff --git a/gl/fcntl.c b/gl/fcntl.c
deleted file mode 100644
index c51e8ded..00000000
--- a/gl/fcntl.c
+++ /dev/null
@@ -1,294 +0,0 @@
-/* Provide file descriptor control.
-
- Copyright (C) 2009, 2010 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 Eric Blake <ebb9@byu.net>. */
-
-#include <config.h>
-
-/* Specification. */
-#include <fcntl.h>
-
-#include <errno.h>
-#include <limits.h>
-#include <stdarg.h>
-#include <unistd.h>
-
-#if !HAVE_FCNTL
-# define rpl_fcntl fcntl
-#endif
-#undef fcntl
-
-#if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
-/* Get declarations of the Win32 API functions. */
-# define WIN32_LEAN_AND_MEAN
-# include <windows.h>
-
-/* Upper bound on getdtablesize(). See lib/getdtablesize.c. */
-# define OPEN_MAX_MAX 0x10000
-
-/* Duplicate OLDFD into the first available slot of at least NEWFD,
- which must be positive, with FLAGS determining whether the duplicate
- will be inheritable. */
-static int
-dupfd (int oldfd, int newfd, int flags)
-{
- /* Mingw has no way to create an arbitrary fd. Iterate until all
- file descriptors less than newfd are filled up. */
- HANDLE curr_process = GetCurrentProcess ();
- HANDLE old_handle = (HANDLE) _get_osfhandle (oldfd);
- unsigned char fds_to_close[OPEN_MAX_MAX / CHAR_BIT];
- unsigned int fds_to_close_bound = 0;
- int result;
- BOOL inherit = flags & O_CLOEXEC ? FALSE : TRUE;
- int mode;
-
- if (newfd < 0 || getdtablesize () <= newfd)
- {
- errno = EINVAL;
- return -1;
- }
- if (old_handle == INVALID_HANDLE_VALUE
- || (mode = setmode (oldfd, O_BINARY)) == -1)
- {
- /* oldfd is not open, or is an unassigned standard file
- descriptor. */
- errno = EBADF;
- return -1;
- }
- setmode (oldfd, mode);
- flags |= mode;
-
- for (;;)
- {
- HANDLE new_handle;
- int duplicated_fd;
- unsigned int index;
-
- if (!DuplicateHandle (curr_process, /* SourceProcessHandle */
- old_handle, /* SourceHandle */
- curr_process, /* TargetProcessHandle */
- (PHANDLE) &new_handle, /* TargetHandle */
- (DWORD) 0, /* DesiredAccess */
- inherit, /* InheritHandle */
- DUPLICATE_SAME_ACCESS)) /* Options */
- {
- /* TODO: Translate GetLastError () into errno. */
- errno = EMFILE;
- result = -1;
- break;
- }
- duplicated_fd = _open_osfhandle ((long) new_handle, flags);
- if (duplicated_fd < 0)
- {
- CloseHandle (new_handle);
- errno = EMFILE;
- result = -1;
- break;
- }
- if (newfd <= duplicated_fd)
- {
- result = duplicated_fd;
- break;
- }
-
- /* Set the bit duplicated_fd in fds_to_close[]. */
- index = (unsigned int) duplicated_fd / CHAR_BIT;
- if (fds_to_close_bound <= index)
- {
- if (sizeof fds_to_close <= index)
- /* Need to increase OPEN_MAX_MAX. */
- abort ();
- memset (fds_to_close + fds_to_close_bound, '\0',
- index + 1 - fds_to_close_bound);
- fds_to_close_bound = index + 1;
- }
- fds_to_close[index] |= 1 << ((unsigned int) duplicated_fd % CHAR_BIT);
- }
-
- /* Close the previous fds that turned out to be too small. */
- {
- int saved_errno = errno;
- unsigned int duplicated_fd;
-
- for (duplicated_fd = 0;
- duplicated_fd < fds_to_close_bound * CHAR_BIT;
- duplicated_fd++)
- if ((fds_to_close[duplicated_fd / CHAR_BIT]
- >> (duplicated_fd % CHAR_BIT))
- & 1)
- close (duplicated_fd);
-
- errno = saved_errno;
- }
-
-# if REPLACE_FCHDIR
- if (0 <= result)
- result = _gl_register_dup (oldfd, result);
-# endif
- return result;
-}
-#endif /* W32 */
-
-/* Perform the specified ACTION on the file descriptor FD, possibly
- using the argument ARG further described below. This replacement
- handles the following actions, and forwards all others on to the
- native fcntl. An unrecognized ACTION returns -1 with errno set to
- EINVAL.
-
- F_DUPFD - duplicate FD, with int ARG being the minimum target fd.
- If successful, return the duplicate, which will be inheritable;
- otherwise return -1 and set errno.
-
- F_DUPFD_CLOEXEC - duplicate FD, with int ARG being the minimum
- target fd. If successful, return the duplicate, which will not be
- inheritable; otherwise return -1 and set errno.
-
- F_GETFD - ARG need not be present. If successful, return a
- non-negative value containing the descriptor flags of FD (only
- FD_CLOEXEC is portable, but other flags may be present); otherwise
- return -1 and set errno. */
-
-int
-rpl_fcntl (int fd, int action, /* arg */...)
-{
- va_list arg;
- int result = -1;
- va_start (arg, action);
- switch (action)
- {
-
-#if !HAVE_FCNTL
- case F_DUPFD:
- {
- int target = va_arg (arg, int);
- result = dupfd (fd, target, 0);
- break;
- }
-#elif FCNTL_DUPFD_BUGGY || REPLACE_FCHDIR
- case F_DUPFD:
- {
- int target = va_arg (arg, int);
- /* Detect invalid target; needed for cygwin 1.5.x. */
- if (target < 0 || getdtablesize () <= target)
- errno = EINVAL;
- else
- {
- result = fcntl (fd, action, target);
-# if REPLACE_FCHDIR
- if (0 <= result)
- result = _gl_register_dup (fd, result);
-# endif
- }
- break;
- } /* F_DUPFD */
-#endif /* FCNTL_DUPFD_BUGGY || REPLACE_FCHDIR */
-
- case F_DUPFD_CLOEXEC:
- {
- int target = va_arg (arg, int);
-
-#if !HAVE_FCNTL
- result = dupfd (fd, target, O_CLOEXEC);
- break;
-#else /* HAVE_FCNTL */
- /* Try the system call first, if the headers claim it exists
- (that is, if GNULIB_defined_F_DUPFD_CLOEXEC is 0), since we
- may be running with a glibc that has the macro but with an
- older kernel that does not support it. Cache the
- information on whether the system call really works, but
- avoid caching failure if the corresponding F_DUPFD fails
- for any reason. 0 = unknown, 1 = yes, -1 = no. */
- static int have_dupfd_cloexec = GNULIB_defined_F_DUPFD_CLOEXEC ? -1 : 0;
- if (0 <= have_dupfd_cloexec)
- {
- result = fcntl (fd, action, target);
- if (0 <= result || errno != EINVAL)
- {
- have_dupfd_cloexec = 1;
-# if REPLACE_FCHDIR
- if (0 <= result)
- result = _gl_register_dup (fd, result);
-# endif
- }
- else
- {
- result = rpl_fcntl (fd, F_DUPFD, target);
- if (result < 0)
- break;
- have_dupfd_cloexec = -1;
- }
- }
- else
- result = rpl_fcntl (fd, F_DUPFD, target);
- if (0 <= result && have_dupfd_cloexec == -1)
- {
- int flags = fcntl (result, F_GETFD);
- if (flags < 0 || fcntl (result, F_SETFD, flags | FD_CLOEXEC) == -1)
- {
- int saved_errno = errno;
- close (result);
- errno = saved_errno;
- result = -1;
- }
- }
- break;
-#endif /* HAVE_FCNTL */
- } /* F_DUPFD_CLOEXEC */
-
-#if !HAVE_FCNTL
- case F_GETFD:
- {
-# if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
- HANDLE handle = (HANDLE) _get_osfhandle (fd);
- DWORD flags;
- if (handle == INVALID_HANDLE_VALUE
- || GetHandleInformation (handle, &flags) == 0)
- errno = EBADF;
- else
- result = (flags & HANDLE_FLAG_INHERIT) ? 0 : FD_CLOEXEC;
-# else /* !W32 */
- /* Use dup2 to reject invalid file descriptors. No way to
- access this information, so punt. */
- if (0 <= dup2 (fd, fd))
- result = 0;
-# endif /* !W32 */
- break;
- } /* F_GETFD */
-#endif /* !HAVE_FCNTL */
-
- /* Implementing F_SETFD on mingw is not trivial - there is no
- API for changing the O_NOINHERIT bit on an fd, and merely
- changing the HANDLE_FLAG_INHERIT bit on the underlying handle
- can lead to odd state. It may be possible by duplicating the
- handle, using _open_osfhandle with the right flags, then
- using dup2 to move the duplicate onto the original, but that
- is not supported for now. */
-
- default:
- {
-#if HAVE_FCNTL
- void *p = va_arg (arg, void *);
- result = fcntl (fd, action, p);
-#else
- errno = EINVAL;
-#endif
- break;
- }
- }
- va_end (arg);
- return result;
-}
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