/* Copy a file descriptor, applying specific flags.
- Copyright (C) 2009 Free Software Foundation, Inc.
+ Copyright (C) 2009-2013 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
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, write to the Free Software Foundation,
- Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
+ with this program; if not, see <http://www.gnu.org/licenses/>. */
#include <config.h>
#include "binary-io.h"
-#if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
-/* Native Woe32 API. */
-
-/* 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
-
-#else
-/* Unix API. */
-
-# ifndef O_CLOEXEC
-# define O_CLOEXEC 0
-# endif
-
-#endif
-
int
dup3 (int oldfd, int newfd, int flags)
{
#if HAVE_DUP3
# undef dup3
+# if HAVE_SETDTABLESIZE
+ /* Avoid a cygwin crasher. */
+ setdtablesize (newfd + 1);
+# endif
/* Try the system call first, if it exists. (We may be running with a glibc
that has the function but with an older kernel that lacks it.) */
{
- int result = dup3 (oldfd, newfd, flags);
- if (!(result < 0 && errno == ENOSYS))
- return result;
+ /* Cache the information whether the system call really exists. */
+ static int have_dup3_really; /* 0 = unknown, 1 = yes, -1 = no */
+ if (have_dup3_really >= 0)
+ {
+ int result = dup3 (oldfd, newfd, flags);
+ if (!(result < 0 && errno == ENOSYS))
+ {
+ have_dup3_really = 1;
+# if REPLACE_FCHDIR
+ if (0 <= result)
+ result = _gl_register_dup (oldfd, newfd);
+# endif
+ return result;
+ }
+ have_dup3_really = -1;
+ }
}
#endif
- if (oldfd < 0 || newfd < 0 || newfd >= getdtablesize ())
+ if (newfd < 0 || newfd >= getdtablesize () || fcntl (oldfd, F_GETFD) == -1)
{
errno = EBADF;
return -1;
return -1;
}
-#if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
-/* Native Woe32 API. */
-
if (flags & O_CLOEXEC)
{
- /* Neither dup() nor dup2() can create a file descriptor with
- O_CLOEXEC = O_NOINHERIT set. We need to use the low-level function
- _open_osfhandle for this. 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;
-
- if (old_handle == INVALID_HANDLE_VALUE)
- {
- /* oldfd is not open, or is an unassigned standard file
- descriptor. */
- errno = EBADF;
- return -1;
- }
-
close (newfd);
-
- 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 */
- FALSE, /* InheritHandle */
- DUPLICATE_SAME_ACCESS)) /* Options */
- {
- errno = EBADF; /* arbitrary */
- result = -1;
- break;
- }
- duplicated_fd = _open_osfhandle ((long) new_handle, flags);
- if (duplicated_fd < 0)
- {
- CloseHandle (new_handle);
- result = -1;
- break;
- }
- if (duplicated_fd > newfd)
- /* Shouldn't happen, since newfd is still closed. */
- abort ();
- if (duplicated_fd == newfd)
- {
- result = newfd;
- break;
- }
-
- /* Set the bit duplicated_fd in fds_to_close[]. */
- index = (unsigned int) duplicated_fd / CHAR_BIT;
- if (index >= fds_to_close_bound)
- {
- if (index >= sizeof (fds_to_close))
- /* 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;
- }
-
- return result;
+ result = fcntl (oldfd, F_DUPFD_CLOEXEC, newfd);
+ if (newfd < result)
+ {
+ close (result);
+ errno = EIO;
+ result = -1;
+ }
+ if (result < 0)
+ return -1;
}
-
- if (dup2 (oldfd, newfd) < 0)
- return -1;
-
-#else
-/* Unix API. */
-
- if (dup2 (oldfd, newfd) < 0)
+ else if (dup2 (oldfd, newfd) < 0)
return -1;
- /* POSIX <http://www.opengroup.org/onlinepubs/9699919799/functions/dup.html>
- says that initially, the FD_CLOEXEC flag is cleared on newfd. */
-
- if (flags & O_CLOEXEC)
- {
- int fcntl_flags;
-
- if ((fcntl_flags = fcntl (newfd, F_GETFD, 0)) < 0
- || fcntl (newfd, F_SETFD, fcntl_flags | FD_CLOEXEC) == -1)
- {
- int saved_errno = errno;
- close (newfd);
- errno = saved_errno;
- return -1;
- }
- }
-
-#endif
-
#if O_BINARY
if (flags & O_BINARY)
- setmode (newfd, O_BINARY);
+ set_binary_mode (newfd, O_BINARY);
else if (flags & O_TEXT)
- setmode (newfd, O_TEXT);
+ set_binary_mode (newfd, O_TEXT);
#endif
return newfd;