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/* Determine whether we can write any file.
Copyright (C) 2007 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 Paul Eggert. */
#include <config.h>
#include "write-any-file.h"
#if HAVE_PRIV_H
# include <priv.h>
#endif
#include <unistd.h>
/* Return true if we know that we can write any file, including
writing directories. */
bool
can_write_any_file (void)
{
static bool initialized;
static bool can_write;
if (! initialized)
{
bool can = false;
#if defined PRIV_EFFECTIVE && defined PRIV_FILE_DAC_WRITE
priv_set_t *pset = priv_allocset ();
if (pset)
{
can =
(getppriv (PRIV_EFFECTIVE, pset) == 0
&& priv_ismember (pset, PRIV_FILE_DAC_WRITE));
priv_freeset (pset);
}
#else
/* In traditional Unix, only root can unlink directories. */
can = (geteuid () == 0);
#endif
can_write = can;
initialized = true;
}
return can_write;
}
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