coreutils/lib/xstat.in
2000-10-29 11:03:01 +00:00

126 lines
3.6 KiB
C

/* @IGNORE@ -*- c -*- */
/* @IGNORE@ This file is a template from which both stat.c and lstat.c
@IGNORE@ are generated. */
/* Work around the bug in some systems whereby @xstat@ succeeds when
given the zero-length file name argument. The @xstat@ from SunOS4.1.4
has this bug.
Copyright (C) 1997-2000 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 2, 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, write to the Free Software Foundation,
Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
/* written by Jim Meyering */
#include <config.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <errno.h>
#ifndef errno
extern int errno;
#endif
@BEGIN_LSTAT_ONLY@
#if HAVE_STDLIB_H
# include <stdlib.h>
#endif
#ifdef STAT_MACROS_BROKEN
# undef S_ISLNK
#endif
#if !defined(S_ISLNK) && defined(S_IFLNK)
# define S_ISLNK(m) (((m) & S_IFMT) == S_IFLNK)
#endif
#ifndef HAVE_DECL_FREE
"this configure-time declaration test was not run"
#endif
#if !HAVE_DECL_FREE
void free ();
#endif
char *xmalloc ();
/* 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 systems, the lstat function already
has the desired semantics (in treating `lstat("symlink/",sbuf)' just like
`lstat("symlink/.",sbuf)', but on Solaris it does not.
If FILE has a trailing slash and specifies a symbolic link,
then append a `.' to FILE and call lstat a second time. */
static int
slash_aware_lstat (const char *file, struct stat *sbuf)
{
size_t len;
char *new_file;
int lstat_result = lstat (file, sbuf);
if (lstat_result != 0 || !S_ISLNK (sbuf->st_mode))
return lstat_result;
len = strlen (file);
if (file[len - 1] != '/')
return lstat_result;
/* FILE refers to a symbolic link and the name ends with a slash.
Append a `.' to FILE and repeat the lstat call. */
/* Add one for the `.' we might have to append, and one more
for the trailing NUL. */
new_file = xmalloc (len + 1 + 1);
memcpy (new_file, file, len);
new_file[len] = '.';
new_file[len + 1] = 0;
lstat_result = lstat (new_file, sbuf);
free (new_file);
return lstat_result;
}
@END_LSTAT_ONLY@
/* This is a wrapper for @xstat@(2).
If FILE is the empty string, fail with errno == ENOENT.
Otherwise, return the result of calling the real @xstat@.
This works around the bug in some systems whereby @xstat@ succeeds when
given the zero-length file name argument. The @xstat@ from SunOS4.1.4
has this bug. */
@BEGIN_LSTAT_ONLY@
/* This function also provides a version of lstat with consistent semantics
when FILE specifies a symbolic link and has a trailing slash. */
@END_LSTAT_ONLY@
int
rpl_@xstat@ (const char *file, struct stat *sbuf)
{
if (file && *file == 0)
{
errno = ENOENT;
return -1;
}
@BEGIN_LSTAT_ONLY@
return slash_aware_lstat (file, sbuf);
@END_LSTAT_ONLY@
@BEGIN_STAT_ONLY@
return stat (file, sbuf);
@END_STAT_ONLY@
}