NetBSD/lib/libc/gen/sysconf.c
jtc 43fa6fe319 If port provides __weak_alias(), provide an Standard C and POSIX pure
identifier namespace by renaming non standard functions and variables
such that they have a leading underscore.  The library will use those
names internally.  Weak aliases are used to provide the original names
to the API.

This is only the first part of this change.  It is most of the functions
which are implemented in C for all NetBSD ports.  Subsequent changes are
to add the same support to the remaining C files, to assembly files, and
to the automagically generated assembly source used for system calls.
When all of the above is done, ports with weak alias support should add
a definition for __weak_alias to <sys/cdefs.h>.
1997-07-21 14:06:24 +00:00

200 lines
5.4 KiB
C

/* $NetBSD: sysconf.c,v 1.5 1997/07/21 14:07:35 jtc Exp $ */
/*-
* Copyright (c) 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Sean Eric Fagan of Cygnus Support.
*
* 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. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. 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[] = "@(#)sysconf.c 8.2 (Berkeley) 3/20/94";
#else
__RCSID("$NetBSD: sysconf.c,v 1.5 1997/07/21 14:07:35 jtc Exp $");
#endif
#endif /* LIBC_SCCS and not lint */
#include "namespace.h"
#include <sys/param.h>
#include <sys/sysctl.h>
#include <sys/time.h>
#include <sys/resource.h>
#include <errno.h>
#include <unistd.h>
#ifdef __weak_alias
__weak_alias(sysconf,_sysconf);
#endif
/*
* sysconf --
* get configurable system variables.
*
* XXX
* POSIX 1003.1 (ISO/IEC 9945-1, 4.8.1.3) states that the variable values
* not change during the lifetime of the calling process. This would seem
* to require that any change to system limits kill all running processes.
* A workaround might be to cache the values when they are first retrieved
* and then simply return the cached value on subsequent calls. This is
* less useful than returning up-to-date values, however.
*/
long
sysconf(name)
int name;
{
struct rlimit rl;
size_t len;
int mib[2], value;
len = sizeof(value);
switch (name) {
/* 1003.1 */
case _SC_ARG_MAX:
mib[0] = CTL_KERN;
mib[1] = KERN_ARGMAX;
break;
case _SC_CHILD_MAX:
return (getrlimit(RLIMIT_NPROC, &rl) ? -1 : rl.rlim_cur);
case _SC_CLK_TCK:
return (CLK_TCK);
case _SC_JOB_CONTROL:
mib[0] = CTL_KERN;
mib[1] = KERN_JOB_CONTROL;
goto yesno;
case _SC_NGROUPS_MAX:
mib[0] = CTL_KERN;
mib[1] = KERN_NGROUPS;
break;
case _SC_OPEN_MAX:
return (getrlimit(RLIMIT_NOFILE, &rl) ? -1 : rl.rlim_cur);
case _SC_STREAM_MAX:
mib[0] = CTL_USER;
mib[1] = USER_STREAM_MAX;
break;
case _SC_TZNAME_MAX:
mib[0] = CTL_USER;
mib[1] = USER_TZNAME_MAX;
break;
case _SC_SAVED_IDS:
mib[0] = CTL_KERN;
mib[1] = KERN_SAVED_IDS;
goto yesno;
case _SC_VERSION:
mib[0] = CTL_KERN;
mib[1] = KERN_POSIX1;
break;
/* 1003.2 */
case _SC_BC_BASE_MAX:
mib[0] = CTL_USER;
mib[1] = USER_BC_BASE_MAX;
break;
case _SC_BC_DIM_MAX:
mib[0] = CTL_USER;
mib[1] = USER_BC_DIM_MAX;
break;
case _SC_BC_SCALE_MAX:
mib[0] = CTL_USER;
mib[1] = USER_BC_SCALE_MAX;
break;
case _SC_BC_STRING_MAX:
mib[0] = CTL_USER;
mib[1] = USER_BC_STRING_MAX;
break;
case _SC_COLL_WEIGHTS_MAX:
mib[0] = CTL_USER;
mib[1] = USER_COLL_WEIGHTS_MAX;
break;
case _SC_EXPR_NEST_MAX:
mib[0] = CTL_USER;
mib[1] = USER_EXPR_NEST_MAX;
break;
case _SC_LINE_MAX:
mib[0] = CTL_USER;
mib[1] = USER_LINE_MAX;
break;
case _SC_RE_DUP_MAX:
mib[0] = CTL_USER;
mib[1] = USER_RE_DUP_MAX;
break;
case _SC_2_VERSION:
mib[0] = CTL_USER;
mib[1] = USER_POSIX2_VERSION;
break;
case _SC_2_C_BIND:
mib[0] = CTL_USER;
mib[1] = USER_POSIX2_C_BIND;
goto yesno;
case _SC_2_C_DEV:
mib[0] = CTL_USER;
mib[1] = USER_POSIX2_C_DEV;
goto yesno;
case _SC_2_CHAR_TERM:
mib[0] = CTL_USER;
mib[1] = USER_POSIX2_CHAR_TERM;
goto yesno;
case _SC_2_FORT_DEV:
mib[0] = CTL_USER;
mib[1] = USER_POSIX2_FORT_DEV;
goto yesno;
case _SC_2_FORT_RUN:
mib[0] = CTL_USER;
mib[1] = USER_POSIX2_FORT_RUN;
goto yesno;
case _SC_2_LOCALEDEF:
mib[0] = CTL_USER;
mib[1] = USER_POSIX2_LOCALEDEF;
goto yesno;
case _SC_2_SW_DEV:
mib[0] = CTL_USER;
mib[1] = USER_POSIX2_SW_DEV;
goto yesno;
case _SC_2_UPE:
mib[0] = CTL_USER;
mib[1] = USER_POSIX2_UPE;
yesno: if (sysctl(mib, 2, &value, &len, NULL, 0) == -1)
return (-1);
if (value == 0)
return (-1);
return (value);
break;
default:
errno = EINVAL;
return (-1);
}
return (sysctl(mib, 2, &value, &len, NULL, 0) == -1 ? -1 : value);
}