95 lines
2.8 KiB
C
95 lines
2.8 KiB
C
|
/* Check the access rights of a file relative to an open directory.
|
||
|
|
Copyright (C) 2009-2020 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 <https://www.gnu.org/licenses/>. */
|
||
|
|
|
||
|
|
/* written by Eric Blake */
|
||
|
|
|
||
|
|
/* If the user's config.h happens to include <unistd.h>, let it include only
|
||
|
|
the system's <unistd.h> here, so that orig_faccessat doesn't recurse to
|
||
|
|
rpl_faccessat. */
|
||
|
|
#define _GL_INCLUDING_UNISTD_H
|
||
|
|
#include <config.h>
|
||
|
|
|
||
|
|
/* Specification. */
|
||
|
|
#include <unistd.h>
|
||
|
|
|
||
|
|
#include <errno.h>
|
||
|
|
#include <fcntl.h>
|
||
|
|
#include <stdlib.h>
|
||
|
|
#include <string.h>
|
||
|
|
#include <sys/stat.h>
|
||
|
|
#undef _GL_INCLUDING_UNISTD_H
|
||
|
|
|
||
|
|
#if HAVE_FACCESSAT
|
||
|
|
static int
|
||
|
|
orig_faccessat (int fd, char const *name, int mode, int flag)
|
||
|
|
{
|
||
|
|
return faccessat (fd, name, mode, flag);
|
||
|
|
}
|
||
|
|
#endif
|
||
|
|
|
||
|
|
/* Write "unistd.h" here, not <unistd.h>, otherwise OSF/1 5.1 DTK cc
|
||
|
|
eliminates this include because of the preliminary #include <unistd.h>
|
||
|
|
above. */
|
||
|
|
#include "unistd.h"
|
||
|
|
|
||
|
|
#ifndef HAVE_ACCESS
|
||
|
|
/* Mingw lacks access, but it also lacks real vs. effective ids, so
|
||
|
|
the gnulib euidaccess module is good enough. */
|
||
|
|
# undef access
|
||
|
|
# define access euidaccess
|
||
|
|
#endif
|
||
|
|
|
||
|
|
#if HAVE_FACCESSAT
|
||
|
|
|
||
|
|
int
|
||
|
|
rpl_faccessat (int fd, char const *file, int mode, int flag)
|
||
|
|
{
|
||
|
|
int result = orig_faccessat (fd, file, mode, flag);
|
||
|
|
|
||
|
|
if (result == 0 && file[strlen (file) - 1] == '/')
|
||
|
|
{
|
||
|
|
struct stat st;
|
||
|
|
result = fstatat (fd, file, &st, 0);
|
||
|
|
if (result == 0 && !S_ISDIR (st.st_mode))
|
||
|
|
{
|
||
|
|
errno = ENOTDIR;
|
||
|
|
return -1;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
return result;
|
||
|
|
}
|
||
|
|
|
||
|
|
#else /* !HAVE_FACCESSAT */
|
||
|
|
|
||
|
|
/* Invoke access or euidaccess on file, FILE, using mode MODE, in the directory
|
||
|
|
open on descriptor FD. If possible, do it without changing the
|
||
|
|
working directory. Otherwise, resort to using save_cwd/fchdir, then
|
||
|
|
(access|euidaccess)/restore_cwd. If either the save_cwd or the
|
||
|
|
restore_cwd fails, then give a diagnostic and exit nonzero.
|
||
|
|
Note that this implementation only supports AT_EACCESS, although some
|
||
|
|
native versions also support AT_SYMLINK_NOFOLLOW. */
|
||
|
|
|
||
|
|
# define AT_FUNC_NAME faccessat
|
||
|
|
# define AT_FUNC_F1 euidaccess
|
||
|
|
# define AT_FUNC_F2 access
|
||
|
|
# define AT_FUNC_USE_F1_COND AT_EACCESS
|
||
|
|
# define AT_FUNC_POST_FILE_PARAM_DECLS , int mode, int flag
|
||
|
|
# define AT_FUNC_POST_FILE_ARGS , mode
|
||
|
|
# include "at-func.c"
|
||
|
|
|
||
|
|
#endif
|