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-rw-r--r--gnu/fchdir.c289
1 files changed, 0 insertions, 289 deletions
diff --git a/gnu/fchdir.c b/gnu/fchdir.c
deleted file mode 100644
index 83d3c33..0000000
--- a/gnu/fchdir.c
+++ /dev/null
@@ -1,289 +0,0 @@
-/* -*- buffer-read-only: t -*- vi: set ro: */
-/* DO NOT EDIT! GENERATED AUTOMATICALLY! */
-/* fchdir replacement.
- Copyright (C) 2006-2010 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/>. */
-
-#include <config.h>
-
-/* Specification. */
-#include <unistd.h>
-
-#include <assert.h>
-#include <dirent.h>
-#include <errno.h>
-#include <fcntl.h>
-#include <stdbool.h>
-#include <stdlib.h>
-#include <string.h>
-#include <sys/types.h>
-#include <sys/stat.h>
-
-#ifndef REPLACE_OPEN_DIRECTORY
-# define REPLACE_OPEN_DIRECTORY 0
-#endif
-
-#ifndef HAVE_CANONICALIZE_FILE_NAME
-# if GNULIB_CANONICALIZE || GNULIB_CANONICALIZE_LGPL
-# define HAVE_CANONICALIZE_FILE_NAME 1
-# else
-# define HAVE_CANONICALIZE_FILE_NAME 0
-# define canonicalize_file_name(name) NULL
-# endif
-#endif
-
-/* This replacement assumes that a directory is not renamed while opened
- through a file descriptor.
-
- FIXME: On mingw, this would be possible to enforce if we were to
- also open a HANDLE to each directory currently visited by a file
- descriptor, since mingw refuses to rename any in-use file system
- object. */
-
-/* Array of file descriptors opened. If REPLACE_OPEN_DIRECTORY or if it points
- to a directory, it stores info about this directory. */
-typedef struct
-{
- char *name; /* Absolute name of the directory, or NULL. */
- /* FIXME - add a DIR* member to make dirfd possible on mingw? */
-} dir_info_t;
-static dir_info_t *dirs;
-static size_t dirs_allocated;
-
-/* Try to ensure dirs has enough room for a slot at index fd; free any
- contents already in that slot. Return false and set errno to
- ENOMEM on allocation failure. */
-static bool
-ensure_dirs_slot (size_t fd)
-{
- if (fd < dirs_allocated)
- free (dirs[fd].name);
- else
- {
- size_t new_allocated;
- dir_info_t *new_dirs;
-
- new_allocated = 2 * dirs_allocated + 1;
- if (new_allocated <= fd)
- new_allocated = fd + 1;
- new_dirs =
- (dirs != NULL
- ? (dir_info_t *) realloc (dirs, new_allocated * sizeof *dirs)
- : (dir_info_t *) malloc (new_allocated * sizeof *dirs));
- if (new_dirs == NULL)
- return false;
- memset (new_dirs + dirs_allocated, 0,
- (new_allocated - dirs_allocated) * sizeof *dirs);
- dirs = new_dirs;
- dirs_allocated = new_allocated;
- }
- return true;
-}
-
-/* Return the canonical name of DIR in malloc'd storage. */
-static char *
-get_name (char const *dir)
-{
- char *result;
- if (REPLACE_OPEN_DIRECTORY || !HAVE_CANONICALIZE_FILE_NAME)
- {
- /* The function canonicalize_file_name has not yet been ported
- to mingw, with all its drive letter and backslash quirks.
- Fortunately, getcwd is reliable in this case, but we ensure
- we can get back to where we started before using it. Treat
- "." as a special case, as it is frequently encountered. */
- char *cwd = getcwd (NULL, 0);
- int saved_errno;
- if (dir[0] == '.' && dir[1] == '\0')
- return cwd;
- if (chdir (cwd))
- return NULL;
- result = chdir (dir) ? NULL : getcwd (NULL, 0);
- saved_errno = errno;
- if (chdir (cwd))
- abort ();
- free (cwd);
- errno = saved_errno;
- }
- else
- {
- /* Avoid changing the directory. */
- result = canonicalize_file_name (dir);
- }
- return result;
-}
-
-/* Hook into the gnulib replacements for open() and close() to keep track
- of the open file descriptors. */
-
-/* Close FD, cleaning up any fd to name mapping if fd was visiting a
- directory. */
-void
-_gl_unregister_fd (int fd)
-{
- if (fd >= 0 && fd < dirs_allocated)
- {
- free (dirs[fd].name);
- dirs[fd].name = NULL;
- }
-}
-
-/* Mark FD as visiting FILENAME. FD must be non-negative, and refer
- to an open file descriptor. If REPLACE_OPEN_DIRECTORY is non-zero,
- this should only be called if FD is visiting a directory. Close FD
- and return -1 if there is insufficient memory to track the
- directory name; otherwise return FD. */
-int
-_gl_register_fd (int fd, const char *filename)
-{
- struct stat statbuf;
-
- assert (0 <= fd);
- if (REPLACE_OPEN_DIRECTORY
- || (fstat (fd, &statbuf) == 0 && S_ISDIR (statbuf.st_mode)))
- {
- if (!ensure_dirs_slot (fd)
- || (dirs[fd].name = get_name (filename)) == NULL)
- {
- int saved_errno = errno;
- close (fd);
- errno = saved_errno;
- return -1;
- }
- }
- return fd;
-}
-
-/* Mark NEWFD as a duplicate of OLDFD; useful from dup, dup2, dup3,
- and fcntl. Both arguments must be valid and distinct file
- descriptors. Close NEWFD and return -1 if OLDFD is tracking a
- directory, but there is insufficient memory to track the same
- directory in NEWFD; otherwise return NEWFD. */
-int
-_gl_register_dup (int oldfd, int newfd)
-{
- assert (0 <= oldfd && 0 <= newfd && oldfd != newfd);
- if (oldfd < dirs_allocated && dirs[oldfd].name)
- {
- /* Duplicated a directory; must ensure newfd is allocated. */
- if (!ensure_dirs_slot (newfd)
- || (dirs[newfd].name = strdup (dirs[oldfd].name)) == NULL)
- {
- int saved_errno = errno;
- close (newfd);
- errno = saved_errno;
- newfd = -1;
- }
- }
- else if (newfd < dirs_allocated)
- {
- /* Duplicated a non-directory; ensure newfd is cleared. */
- free (dirs[newfd].name);
- dirs[newfd].name = NULL;
- }
- return newfd;
-}
-
-/* If FD is currently visiting a directory, then return the name of
- that directory. Otherwise, return NULL and set errno. */
-const char *
-_gl_directory_name (int fd)
-{
- if (0 <= fd && fd < dirs_allocated && dirs[fd].name != NULL)
- return dirs[fd].name;
- /* At this point, fd is either invalid, or open but not a directory.
- If dup2 fails, errno is correctly EBADF. */
- if (0 <= fd)
- {
- if (dup2 (fd, fd) == fd)
- errno = ENOTDIR;
- }
- else
- errno = EBADF;
- return NULL;
-}
-
-#if REPLACE_OPEN_DIRECTORY
-/* Return stat information about FD in STATBUF. Needed when
- rpl_open() used a dummy file to work around an open() that can't
- normally visit directories. */
-# undef fstat
-int
-rpl_fstat (int fd, struct stat *statbuf)
-{
- if (0 <= fd && fd < dirs_allocated && dirs[fd].name != NULL)
- return stat (dirs[fd].name, statbuf);
- return fstat (fd, statbuf);
-}
-#endif
-
-/* Override opendir() and closedir(), to keep track of the open file
- descriptors. Needed because there is a function dirfd(). */
-
-int
-rpl_closedir (DIR *dp)
-#undef closedir
-{
- int fd = dirfd (dp);
- int retval = closedir (dp);
-
- if (retval >= 0)
- _gl_unregister_fd (fd);
- return retval;
-}
-
-DIR *
-rpl_opendir (const char *filename)
-#undef opendir
-{
- DIR *dp;
-
- dp = opendir (filename);
- if (dp != NULL)
- {
- int fd = dirfd (dp);
- if (0 <= fd && _gl_register_fd (fd, filename) != fd)
- {
- int saved_errno = errno;
- closedir (dp);
- errno = saved_errno;
- return NULL;
- }
- }
- return dp;
-}
-
-/* Override dup(), to keep track of open file descriptors. */
-
-int
-rpl_dup (int oldfd)
-#undef dup
-{
- int newfd = dup (oldfd);
-
- if (0 <= newfd)
- newfd = _gl_register_dup (oldfd, newfd);
- return newfd;
-}
-
-
-/* Implement fchdir() in terms of chdir(). */
-
-int
-fchdir (int fd)
-{
- const char *name = _gl_directory_name (fd);
- return name ? chdir (name) : -1;
-}
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-27 22:38:51 +0000