--- /dev/null
+/* -*- buffer-read-only: t -*- vi: set ro: */
+/* DO NOT EDIT! GENERATED AUTOMATICALLY! */
+/* provide a replacement openat function
+ Copyright (C) 2004-2010 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 Jim Meyering */
+
+#include <config.h>
+
+#include "openat.h"
+
+#include <stdarg.h>
+#include <stddef.h>
+#include <string.h>
+#include <sys/stat.h>
+
+#include "dirname.h" /* solely for definition of IS_ABSOLUTE_FILE_NAME */
+#include "openat-priv.h"
+#include "save-cwd.h"
+
+#if HAVE_OPENAT
+
+# undef openat
+
+/* Like openat, but work around Solaris 9 bugs with trailing slash. */
+int
+rpl_openat (int dfd, char const *filename, int flags, ...)
+{
+ mode_t mode;
+ int fd;
+
+ mode = 0;
+ if (flags & O_CREAT)
+ {
+ va_list arg;
+ va_start (arg, flags);
+
+ /* We have to use PROMOTED_MODE_T instead of mode_t, otherwise GCC 4
+ creates crashing code when 'mode_t' is smaller than 'int'. */
+ mode = va_arg (arg, PROMOTED_MODE_T);
+
+ va_end (arg);
+ }
+
+#if OPEN_TRAILING_SLASH_BUG
+ /* If the filename ends in a slash and one of O_CREAT, O_WRONLY, O_RDWR
+ is specified, then fail.
+ Rationale: POSIX <http://www.opengroup.org/susv3/basedefs/xbd_chap04.html>
+ says that
+ "A pathname that contains at least one non-slash character and that
+ ends with one or more trailing slashes shall be resolved as if a
+ single dot character ( '.' ) were appended to the pathname."
+ and
+ "The special filename dot shall refer to the directory specified by
+ its predecessor."
+ If the named file already exists as a directory, then
+ - if O_CREAT is specified, open() must fail because of the semantics
+ of O_CREAT,
+ - if O_WRONLY or O_RDWR is specified, open() must fail because POSIX
+ <http://www.opengroup.org/susv3/functions/open.html> says that it
+ fails with errno = EISDIR in this case.
+ If the named file does not exist or does not name a directory, then
+ - if O_CREAT is specified, open() must fail since open() cannot create
+ directories,
+ - if O_WRONLY or O_RDWR is specified, open() must fail because the
+ file does not contain a '.' directory. */
+ if (flags & (O_CREAT | O_WRONLY | O_RDWR))
+ {
+ size_t len = strlen (filename);
+ if (len > 0 && filename[len - 1] == '/')
+ {
+ errno = EISDIR;
+ return -1;
+ }
+ }
+#endif
+
+ fd = openat (dfd, filename, flags, mode);
+
+#if OPEN_TRAILING_SLASH_BUG
+ /* If the filename ends in a slash and fd does not refer to a directory,
+ then fail.
+ Rationale: POSIX <http://www.opengroup.org/susv3/basedefs/xbd_chap04.html>
+ says that
+ "A pathname that contains at least one non-slash character and that
+ ends with one or more trailing slashes shall be resolved as if a
+ single dot character ( '.' ) were appended to the pathname."
+ and
+ "The special filename dot shall refer to the directory specified by
+ its predecessor."
+ If the named file without the slash is not a directory, open() must fail
+ with ENOTDIR. */
+ if (fd >= 0)
+ {
+ /* We know len is positive, since open did not fail with ENOENT. */
+ size_t len = strlen (filename);
+ if (filename[len - 1] == '/')
+ {
+ struct stat statbuf;
+
+ if (fstat (fd, &statbuf) >= 0 && !S_ISDIR (statbuf.st_mode))
+ {
+ close (fd);
+ errno = ENOTDIR;
+ return -1;
+ }
+ }
+ }
+#endif
+
+ return fd;
+}
+
+#else /* !HAVE_OPENAT */
+
+/* Replacement for Solaris' openat function.
+ <http://www.google.com/search?q=openat+site:docs.sun.com>
+ First, try to simulate it via open ("/proc/self/fd/FD/FILE").
+ Failing that, simulate it by doing save_cwd/fchdir/open/restore_cwd.
+ If either the save_cwd or the restore_cwd fails (relatively unlikely),
+ then give a diagnostic and exit nonzero.
+ Otherwise, upon failure, set errno and return -1, as openat does.
+ Upon successful completion, return a file descriptor. */
+int
+openat (int fd, char const *file, int flags, ...)
+{
+ mode_t mode = 0;
+
+ if (flags & O_CREAT)
+ {
+ va_list arg;
+ va_start (arg, flags);
+
+ /* We have to use PROMOTED_MODE_T instead of mode_t, otherwise GCC 4
+ creates crashing code when 'mode_t' is smaller than 'int'. */
+ mode = va_arg (arg, PROMOTED_MODE_T);
+
+ va_end (arg);
+ }
+
+ return openat_permissive (fd, file, flags, mode, NULL);
+}
+
+/* Like openat (FD, FILE, FLAGS, MODE), but if CWD_ERRNO is
+ nonnull, set *CWD_ERRNO to an errno value if unable to save
+ or restore the initial working directory. This is needed only
+ the first time remove.c's remove_dir opens a command-line
+ directory argument.
+
+ If a previous attempt to restore the current working directory
+ failed, then we must not even try to access a `.'-relative name.
+ It is the caller's responsibility not to call this function
+ in that case. */
+
+int
+openat_permissive (int fd, char const *file, int flags, mode_t mode,
+ int *cwd_errno)
+{
+ struct saved_cwd saved_cwd;
+ int saved_errno;
+ int err;
+ bool save_ok;
+
+ if (fd == AT_FDCWD || IS_ABSOLUTE_FILE_NAME (file))
+ return open (file, flags, mode);
+
+ {
+ char buf[OPENAT_BUFFER_SIZE];
+ char *proc_file = openat_proc_name (buf, fd, file);
+ if (proc_file)
+ {
+ int open_result = open (proc_file, flags, mode);
+ int open_errno = errno;
+ if (proc_file != buf)
+ free (proc_file);
+ /* If the syscall succeeds, or if it fails with an unexpected
+ errno value, then return right away. Otherwise, fall through
+ and resort to using save_cwd/restore_cwd. */
+ if (0 <= open_result || ! EXPECTED_ERRNO (open_errno))
+ {
+ errno = open_errno;
+ return open_result;
+ }
+ }
+ }
+
+ save_ok = (save_cwd (&saved_cwd) == 0);
+ if (! save_ok)
+ {
+ if (! cwd_errno)
+ openat_save_fail (errno);
+ *cwd_errno = errno;
+ }
+ if (0 <= fd && fd == saved_cwd.desc)
+ {
+ /* If saving the working directory collides with the user's
+ requested fd, then the user's fd must have been closed to
+ begin with. */
+ free_cwd (&saved_cwd);
+ errno = EBADF;
+ return -1;
+ }
+
+ err = fchdir (fd);
+ saved_errno = errno;
+
+ if (! err)
+ {
+ err = open (file, flags, mode);
+ saved_errno = errno;
+ if (save_ok && restore_cwd (&saved_cwd) != 0)
+ {
+ if (! cwd_errno)
+ {
+ /* Don't write a message to just-created fd 2. */
+ saved_errno = errno;
+ if (err == STDERR_FILENO)
+ close (err);
+ openat_restore_fail (saved_errno);
+ }
+ *cwd_errno = errno;
+ }
+ }
+
+ free_cwd (&saved_cwd);
+ errno = saved_errno;
+ return err;
+}
+
+/* Return true if our openat implementation must resort to
+ using save_cwd and restore_cwd. */
+bool
+openat_needs_fchdir (void)
+{
+ bool needs_fchdir = true;
+ int fd = open ("/", O_RDONLY);
+
+ if (0 <= fd)
+ {
+ char buf[OPENAT_BUFFER_SIZE];
+ char *proc_file = openat_proc_name (buf, fd, ".");
+ if (proc_file)
+ {
+ needs_fchdir = false;
+ if (proc_file != buf)
+ free (proc_file);
+ }
+ close (fd);
+ }
+
+ return needs_fchdir;
+}
+
+#endif /* !HAVE_OPENAT */
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