mirror of
https://git.savannah.gnu.org/git/emacs.git
synced 2024-11-26 07:33:47 +00:00
98 lines
3.4 KiB
C
98 lines
3.4 KiB
C
/* Work around a bug of lstat on some systems
|
|
|
|
Copyright (C) 1997-2006, 2008-2017 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 */
|
|
|
|
/* If the user's config.h happens to include <sys/stat.h>, let it include only
|
|
the system's <sys/stat.h> here, so that orig_lstat doesn't recurse to
|
|
rpl_lstat. */
|
|
#define __need_system_sys_stat_h
|
|
#include <config.h>
|
|
|
|
#if !HAVE_LSTAT
|
|
/* On systems that lack symlinks, our replacement <sys/stat.h> already
|
|
defined lstat as stat, so there is nothing further to do other than
|
|
avoid an empty file. */
|
|
typedef int dummy;
|
|
#else /* HAVE_LSTAT */
|
|
|
|
/* Get the original definition of lstat. It might be defined as a macro. */
|
|
# include <sys/types.h>
|
|
# include <sys/stat.h>
|
|
# undef __need_system_sys_stat_h
|
|
|
|
static int
|
|
orig_lstat (const char *filename, struct stat *buf)
|
|
{
|
|
return lstat (filename, buf);
|
|
}
|
|
|
|
/* Specification. */
|
|
/* Write "sys/stat.h" here, not <sys/stat.h>, otherwise OSF/1 5.1 DTK cc
|
|
eliminates this include because of the preliminary #include <sys/stat.h>
|
|
above. */
|
|
# include "sys/stat.h"
|
|
|
|
# include <string.h>
|
|
# include <errno.h>
|
|
|
|
/* lstat works differently on Linux and Solaris systems. POSIX (see
|
|
"pathname resolution" in the glossary) requires that programs like
|
|
'ls' take into consideration the fact that FILE has a trailing slash
|
|
when FILE is a symbolic link. On Linux and Solaris 10 systems, the
|
|
lstat function already has the desired semantics (in treating
|
|
'lstat ("symlink/", sbuf)' just like 'lstat ("symlink/.", sbuf)',
|
|
but on Solaris 9 and earlier it does not.
|
|
|
|
If FILE has a trailing slash and specifies a symbolic link,
|
|
then use stat() to get more info on the referent of FILE.
|
|
If the referent is a non-directory, then set errno to ENOTDIR
|
|
and return -1. Otherwise, return stat's result. */
|
|
|
|
int
|
|
rpl_lstat (const char *file, struct stat *sbuf)
|
|
{
|
|
size_t len;
|
|
int lstat_result = orig_lstat (file, sbuf);
|
|
|
|
if (lstat_result != 0)
|
|
return lstat_result;
|
|
|
|
/* This replacement file can blindly check against '/' rather than
|
|
using the ISSLASH macro, because all platforms with '\\' either
|
|
lack symlinks (mingw) or have working lstat (cygwin) and thus do
|
|
not compile this file. 0 len should have already been filtered
|
|
out above, with a failure return of ENOENT. */
|
|
len = strlen (file);
|
|
if (file[len - 1] != '/' || S_ISDIR (sbuf->st_mode))
|
|
return 0;
|
|
|
|
/* At this point, a trailing slash is only permitted on
|
|
symlink-to-dir; but it should have found information on the
|
|
directory, not the symlink. Call stat() to get info about the
|
|
link's referent. Our replacement stat guarantees valid results,
|
|
even if the symlink is not pointing to a directory. */
|
|
if (!S_ISLNK (sbuf->st_mode))
|
|
{
|
|
errno = ENOTDIR;
|
|
return -1;
|
|
}
|
|
return stat (file, sbuf);
|
|
}
|
|
|
|
#endif /* HAVE_LSTAT */
|