NetBSD/lib/libc/gen/confstr.c

99 lines
2.9 KiB
C

/* $NetBSD: confstr.c,v 1.12 2006/12/03 00:39:19 christos Exp $ */
/*-
* Copyright (c) 1993
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
#if defined(LIBC_SCCS) && !defined(lint)
#if 0
static char sccsid[] = "@(#)confstr.c 8.1 (Berkeley) 6/4/93";
#else
__RCSID("$NetBSD: confstr.c,v 1.12 2006/12/03 00:39:19 christos Exp $");
#endif
#endif /* LIBC_SCCS and not lint */
#include "namespace.h"
#include <sys/param.h>
#include <sys/sysctl.h>
#include <errno.h>
#include <paths.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#ifdef __weak_alias
__weak_alias(confstr,_confstr)
#endif
size_t
confstr(name, buf, len)
int name;
char *buf;
size_t len;
{
size_t tlen;
int mib[2], sverrno;
char *p;
/*
* POSIX 1003.2 requires errors to return 0 --
* that is *really* useful.
*/
switch (name) {
case _CS_PATH:
mib[0] = CTL_USER;
mib[1] = USER_CS_PATH;
if (sysctl(mib, 2, NULL, &tlen, NULL, 0) == -1)
return 0;
if (len != 0 && buf != NULL) {
if ((p = malloc(tlen)) == NULL)
return 0;
if (sysctl(mib, 2, p, &tlen, NULL, 0) == -1) {
sverrno = errno;
free(p);
errno = sverrno;
return 0;
}
/*
* POSIX 1003.2 requires partial return of
* the string -- that is even more useful.
*/
(void)strncpy(buf, p, len - 1);
buf[len - 1] = '\0';
free(p);
}
return tlen + 1;
default:
errno = EINVAL;
return 0;
}
/* NOTREACHED */
}