rm_/lib/xfts.c
2022-07-28 14:16:50 +08:00

66 lines
2.3 KiB
C

/* xfts.c -- a wrapper for fts_open
Copyright (C) 2003-2022 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 Jim Meyering. */
#include <config.h>
#include <stdbool.h>
#include <stdlib.h>
#include <errno.h>
#include <assert.h>
#include "xalloc.h"
#include "xfts.h"
/* Fail with a proper diagnostic if fts_open fails. */
FTS *
xfts_open (char * const *argv, int options,
int (*compar) (const FTSENT **, const FTSENT **))
{
FTS *fts = fts_open (argv, options | FTS_CWDFD, compar);
if (fts == NULL)
{
/* This can fail in two ways: out of memory or with errno==EINVAL,
which indicates it was called with invalid bit_flags. */
assert (errno != EINVAL);
xalloc_die ();
}
return fts;
}
/* When fts_read returns FTS_DC to indicate a directory cycle,
it may or may not indicate a real problem. When a program like
chgrp performs a recursive traversal that requires traversing
symbolic links, it is *not* a problem. However, when invoked
with "-P -R", it deserves a warning. The fts_options member
records the options that control this aspect of fts's behavior,
so test that. */
bool
cycle_warning_required (FTS const *fts, FTSENT const *ent)
{
#define ISSET(Fts,Opt) ((Fts)->fts_options & (Opt))
/* When dereferencing no symlinks, or when dereferencing only
those listed on the command line and we're not processing
a command-line argument, then a cycle is a serious problem. */
return ((ISSET (fts, FTS_PHYSICAL) && !ISSET (fts, FTS_COMFOLLOW))
|| (ISSET (fts, FTS_PHYSICAL) && ISSET (fts, FTS_COMFOLLOW)
&& ent->fts_level != FTS_ROOTLEVEL));
}