freebsd-nq/lib/libc/gen/sysconf.c
Pedro F. Giffuni 8a16b7a18f General further adoption of SPDX licensing ID tags.
Mainly focus on files that use BSD 3-Clause license.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.

Special thanks to Wind River for providing access to "The Duke of
Highlander" tool: an older (2014) run over FreeBSD tree was useful as a
starting point.
2017-11-20 19:49:47 +00:00

624 lines
16 KiB
C

/*-
* SPDX-License-Identifier: BSD-3-Clause
*
* 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. 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.
*/
#if defined(LIBC_SCCS) && !defined(lint)
static char sccsid[] = "@(#)sysconf.c 8.2 (Berkeley) 3/20/94";
#endif /* LIBC_SCCS and not lint */
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "namespace.h"
#include <sys/param.h>
#include <sys/time.h>
#include <sys/sysctl.h>
#include <sys/resource.h>
#include <sys/socket.h>
#include <elf.h>
#include <errno.h>
#include <limits.h>
#include <paths.h>
#include <pthread.h> /* we just need the limits */
#include <semaphore.h>
#include <time.h>
#include <unistd.h>
#include "un-namespace.h"
#include "../stdlib/atexit.h"
#include "tzfile.h" /* from ../../../contrib/tzcode/stdtime */
#include "libc_private.h"
#define _PATH_ZONEINFO TZDIR /* from tzfile.h */
/*
* 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(int name)
{
struct rlimit rl;
size_t len;
int mib[2], sverrno, value;
long lvalue, defaultresult;
const char *path;
defaultresult = -1;
switch (name) {
case _SC_ARG_MAX:
mib[0] = CTL_KERN;
mib[1] = KERN_ARGMAX;
break;
case _SC_CHILD_MAX:
if (getrlimit(RLIMIT_NPROC, &rl) != 0)
return (-1);
if (rl.rlim_cur == RLIM_INFINITY)
return (-1);
if (rl.rlim_cur > LONG_MAX) {
errno = EOVERFLOW;
return (-1);
}
return ((long)rl.rlim_cur);
case _SC_CLK_TCK:
return (CLK_TCK);
case _SC_NGROUPS_MAX:
mib[0] = CTL_KERN;
mib[1] = KERN_NGROUPS;
break;
case _SC_OPEN_MAX:
if (getrlimit(RLIMIT_NOFILE, &rl) != 0)
return (-1);
if (rl.rlim_cur == RLIM_INFINITY)
return (-1);
if (rl.rlim_cur > LONG_MAX) {
errno = EOVERFLOW;
return (-1);
}
return ((long)rl.rlim_cur);
case _SC_STREAM_MAX:
if (getrlimit(RLIMIT_NOFILE, &rl) != 0)
return (-1);
if (rl.rlim_cur == RLIM_INFINITY)
return (-1);
if (rl.rlim_cur > LONG_MAX) {
errno = EOVERFLOW;
return (-1);
}
/*
* struct __sFILE currently has a limitation that
* file descriptors must fit in a signed short.
* This doesn't precisely capture the letter of POSIX
* but approximates the spirit.
*/
if (rl.rlim_cur > SHRT_MAX)
return (SHRT_MAX);
return ((long)rl.rlim_cur);
case _SC_JOB_CONTROL:
return (_POSIX_JOB_CONTROL);
case _SC_SAVED_IDS:
/* XXX - must be 1 */
mib[0] = CTL_KERN;
mib[1] = KERN_SAVED_IDS;
goto yesno;
case _SC_VERSION:
mib[0] = CTL_KERN;
mib[1] = KERN_POSIX1;
break;
case _SC_BC_BASE_MAX:
return (BC_BASE_MAX);
case _SC_BC_DIM_MAX:
return (BC_DIM_MAX);
case _SC_BC_SCALE_MAX:
return (BC_SCALE_MAX);
case _SC_BC_STRING_MAX:
return (BC_STRING_MAX);
case _SC_COLL_WEIGHTS_MAX:
return (COLL_WEIGHTS_MAX);
case _SC_EXPR_NEST_MAX:
return (EXPR_NEST_MAX);
case _SC_LINE_MAX:
return (LINE_MAX);
case _SC_RE_DUP_MAX:
return (RE_DUP_MAX);
case _SC_2_VERSION:
/*
* This is something of a lie, but it would be silly at
* this point to try to deduce this from the contents
* of the filesystem.
*/
return (_POSIX2_VERSION);
case _SC_2_C_BIND:
return (_POSIX2_C_BIND);
case _SC_2_C_DEV:
return (_POSIX2_C_DEV);
case _SC_2_CHAR_TERM:
return (_POSIX2_CHAR_TERM);
case _SC_2_FORT_DEV:
return (_POSIX2_FORT_DEV);
case _SC_2_FORT_RUN:
return (_POSIX2_FORT_RUN);
case _SC_2_LOCALEDEF:
return (_POSIX2_LOCALEDEF);
case _SC_2_SW_DEV:
return (_POSIX2_SW_DEV);
case _SC_2_UPE:
return (_POSIX2_UPE);
case _SC_TZNAME_MAX:
path = _PATH_ZONEINFO;
do_NAME_MAX:
sverrno = errno;
errno = 0;
lvalue = pathconf(path, _PC_NAME_MAX);
if (lvalue == -1 && errno != 0)
return (-1);
errno = sverrno;
return (lvalue);
case _SC_ASYNCHRONOUS_IO:
#if _POSIX_ASYNCHRONOUS_IO == 0
mib[0] = CTL_P1003_1B;
mib[1] = CTL_P1003_1B_ASYNCHRONOUS_IO;
break;
#else
return (_POSIX_ASYNCHRONOUS_IO);
#endif
case _SC_MAPPED_FILES:
return (_POSIX_MAPPED_FILES);
case _SC_MEMLOCK:
return (_POSIX_MEMLOCK);
case _SC_MEMLOCK_RANGE:
return (_POSIX_MEMLOCK_RANGE);
case _SC_MEMORY_PROTECTION:
return (_POSIX_MEMORY_PROTECTION);
case _SC_MESSAGE_PASSING:
#if _POSIX_MESSAGE_PASSING == 0
mib[0] = CTL_P1003_1B;
mib[1] = CTL_P1003_1B_MESSAGE_PASSING;
goto yesno;
#else
return (_POSIX_MESSAGE_PASSING);
#endif
case _SC_PRIORITIZED_IO:
#if _POSIX_PRIORITIZED_IO == 0
mib[0] = CTL_P1003_1B;
mib[1] = CTL_P1003_1B_PRIORITIZED_IO;
goto yesno;
#else
return (_POSIX_PRIORITIZED_IO);
#endif
case _SC_PRIORITY_SCHEDULING:
#if _POSIX_PRIORITY_SCHEDULING == 0
mib[0] = CTL_P1003_1B;
mib[1] = CTL_P1003_1B_PRIORITY_SCHEDULING;
goto yesno;
#else
return (_POSIX_PRIORITY_SCHEDULING);
#endif
case _SC_REALTIME_SIGNALS:
#if _POSIX_REALTIME_SIGNALS == 0
mib[0] = CTL_P1003_1B;
mib[1] = CTL_P1003_1B_REALTIME_SIGNALS;
goto yesno;
#else
return (_POSIX_REALTIME_SIGNALS);
#endif
case _SC_SEMAPHORES:
#if _POSIX_SEMAPHORES == 0
mib[0] = CTL_P1003_1B;
mib[1] = CTL_P1003_1B_SEMAPHORES;
goto yesno;
#else
return (_POSIX_SEMAPHORES);
#endif
case _SC_FSYNC:
return (_POSIX_FSYNC);
case _SC_SHARED_MEMORY_OBJECTS:
return (_POSIX_SHARED_MEMORY_OBJECTS);
case _SC_SYNCHRONIZED_IO:
#if _POSIX_SYNCHRONIZED_IO == 0
mib[0] = CTL_P1003_1B;
mib[1] = CTL_P1003_1B_SYNCHRONIZED_IO;
goto yesno;
#else
return (_POSIX_SYNCHRONIZED_IO);
#endif
case _SC_TIMERS:
#if _POSIX_TIMERS == 0
mib[0] = CTL_P1003_1B;
mib[1] = CTL_P1003_1B_TIMERS;
goto yesno;
#else
return (_POSIX_TIMERS);
#endif
case _SC_AIO_LISTIO_MAX:
mib[0] = CTL_P1003_1B;
mib[1] = CTL_P1003_1B_AIO_LISTIO_MAX;
break;
case _SC_AIO_MAX:
mib[0] = CTL_P1003_1B;
mib[1] = CTL_P1003_1B_AIO_MAX;
break;
case _SC_AIO_PRIO_DELTA_MAX:
mib[0] = CTL_P1003_1B;
mib[1] = CTL_P1003_1B_AIO_PRIO_DELTA_MAX;
break;
case _SC_DELAYTIMER_MAX:
mib[0] = CTL_P1003_1B;
mib[1] = CTL_P1003_1B_DELAYTIMER_MAX;
goto yesno;
case _SC_MQ_OPEN_MAX:
mib[0] = CTL_P1003_1B;
mib[1] = CTL_P1003_1B_MQ_OPEN_MAX;
goto yesno;
case _SC_PAGESIZE:
defaultresult = getpagesize();
mib[0] = CTL_P1003_1B;
mib[1] = CTL_P1003_1B_PAGESIZE;
goto yesno;
case _SC_RTSIG_MAX:
mib[0] = CTL_P1003_1B;
mib[1] = CTL_P1003_1B_RTSIG_MAX;
goto yesno;
case _SC_SEM_NSEMS_MAX:
return (-1);
case _SC_SEM_VALUE_MAX:
return (SEM_VALUE_MAX);
case _SC_SIGQUEUE_MAX:
mib[0] = CTL_P1003_1B;
mib[1] = CTL_P1003_1B_SIGQUEUE_MAX;
goto yesno;
case _SC_TIMER_MAX:
mib[0] = CTL_P1003_1B;
mib[1] = CTL_P1003_1B_TIMER_MAX;
yesno:
len = sizeof(value);
if (sysctl(mib, 2, &value, &len, NULL, 0) == -1)
return (-1);
if (value == 0)
return (defaultresult);
return ((long)value);
case _SC_2_PBS:
case _SC_2_PBS_ACCOUNTING:
case _SC_2_PBS_CHECKPOINT:
case _SC_2_PBS_LOCATE:
case _SC_2_PBS_MESSAGE:
case _SC_2_PBS_TRACK:
#if _POSIX2_PBS == 0
#error "don't know how to determine _SC_2_PBS"
/*
* This probably requires digging through the filesystem
* to see if the appropriate package has been installed.
* Since we don't currently support this option at all,
* it's not worth the effort to write the code now.
* Figuring out which of the sub-options are supported
* would be even more difficult, so it's probably easier
* to always say ``no''.
*/
#else
return (_POSIX2_PBS);
#endif
case _SC_ADVISORY_INFO:
#if _POSIX_ADVISORY_INFO == 0
#error "_POSIX_ADVISORY_INFO"
#else
return (_POSIX_ADVISORY_INFO);
#endif
case _SC_BARRIERS:
#if _POSIX_BARRIERS == 0
#error "_POSIX_BARRIERS"
#else
return (_POSIX_BARRIERS);
#endif
case _SC_CLOCK_SELECTION:
#if _POSIX_CLOCK_SELECTION == 0
#error "_POSIX_CLOCK_SELECTION"
#else
return (_POSIX_CLOCK_SELECTION);
#endif
case _SC_CPUTIME:
return (_POSIX_CPUTIME);
#ifdef notdef
case _SC_FILE_LOCKING:
/*
* XXX - The standard doesn't tell us how to define
* _POSIX_FILE_LOCKING, so we can't answer this one.
*/
#endif
/*
* SUSv4tc1 says the following about _SC_GETGR_R_SIZE_MAX and
* _SC_GETPW_R_SIZE_MAX:
* Note that sysconf(_SC_GETGR_R_SIZE_MAX) may return -1 if
* there is no hard limit on the size of the buffer needed to
* store all the groups returned.
*/
case _SC_GETGR_R_SIZE_MAX:
case _SC_GETPW_R_SIZE_MAX:
return (-1);
case _SC_HOST_NAME_MAX:
return (MAXHOSTNAMELEN - 1); /* does not include \0 */
case _SC_LOGIN_NAME_MAX:
return (MAXLOGNAME);
case _SC_MONOTONIC_CLOCK:
#if _POSIX_MONOTONIC_CLOCK == 0
#error "_POSIX_MONOTONIC_CLOCK"
#else
return (_POSIX_MONOTONIC_CLOCK);
#endif
#if _POSIX_MESSAGE_PASSING > -1
case _SC_MQ_PRIO_MAX:
return (MQ_PRIO_MAX);
#endif
case _SC_READER_WRITER_LOCKS:
return (_POSIX_READER_WRITER_LOCKS);
case _SC_REGEXP:
return (_POSIX_REGEXP);
case _SC_SHELL:
return (_POSIX_SHELL);
case _SC_SPAWN:
return (_POSIX_SPAWN);
case _SC_SPIN_LOCKS:
return (_POSIX_SPIN_LOCKS);
case _SC_SPORADIC_SERVER:
#if _POSIX_SPORADIC_SERVER == 0
#error "_POSIX_SPORADIC_SERVER"
#else
return (_POSIX_SPORADIC_SERVER);
#endif
case _SC_THREAD_ATTR_STACKADDR:
return (_POSIX_THREAD_ATTR_STACKADDR);
case _SC_THREAD_ATTR_STACKSIZE:
return (_POSIX_THREAD_ATTR_STACKSIZE);
case _SC_THREAD_CPUTIME:
return (_POSIX_THREAD_CPUTIME);
case _SC_THREAD_DESTRUCTOR_ITERATIONS:
return (PTHREAD_DESTRUCTOR_ITERATIONS);
case _SC_THREAD_KEYS_MAX:
return (PTHREAD_KEYS_MAX);
case _SC_THREAD_PRIO_INHERIT:
return (_POSIX_THREAD_PRIO_INHERIT);
case _SC_THREAD_PRIO_PROTECT:
return (_POSIX_THREAD_PRIO_PROTECT);
case _SC_THREAD_PRIORITY_SCHEDULING:
return (_POSIX_THREAD_PRIORITY_SCHEDULING);
case _SC_THREAD_PROCESS_SHARED:
return (_POSIX_THREAD_PROCESS_SHARED);
case _SC_THREAD_SAFE_FUNCTIONS:
return (_POSIX_THREAD_SAFE_FUNCTIONS);
case _SC_THREAD_STACK_MIN:
return (PTHREAD_STACK_MIN);
case _SC_THREAD_THREADS_MAX:
return (PTHREAD_THREADS_MAX); /* XXX wrong type! */
case _SC_TIMEOUTS:
return (_POSIX_TIMEOUTS);
case _SC_THREADS:
return (_POSIX_THREADS);
case _SC_TRACE:
#if _POSIX_TRACE == 0
#error "_POSIX_TRACE"
/* While you're implementing this, also do the ones below. */
#else
return (_POSIX_TRACE);
#endif
#if _POSIX_TRACE > -1
case _SC_TRACE_EVENT_FILTER:
return (_POSIX_TRACE_EVENT_FILTER);
case _SC_TRACE_INHERIT:
return (_POSIX_TRACE_INHERIT);
case _SC_TRACE_LOG:
return (_POSIX_TRACE_LOG);
#endif
case _SC_TTY_NAME_MAX:
path = _PATH_DEV;
goto do_NAME_MAX;
case _SC_TYPED_MEMORY_OBJECTS:
#if _POSIX_TYPED_MEMORY_OBJECTS == 0
#error "_POSIX_TYPED_MEMORY_OBJECTS"
#else
return (_POSIX_TYPED_MEMORY_OBJECTS);
#endif
case _SC_V6_ILP32_OFF32:
#if _V6_ILP32_OFF32 == 0
if (sizeof(int) * CHAR_BIT == 32 &&
sizeof(int) == sizeof(long) &&
sizeof(long) == sizeof(void *) &&
sizeof(void *) == sizeof(off_t))
return 1;
else
return -1;
#else
return (_V6_ILP32_OFF32);
#endif
case _SC_V6_ILP32_OFFBIG:
#if _V6_ILP32_OFFBIG == 0
if (sizeof(int) * CHAR_BIT == 32 &&
sizeof(int) == sizeof(long) &&
sizeof(long) == sizeof(void *) &&
sizeof(off_t) * CHAR_BIT >= 64)
return 1;
else
return -1;
#else
return (_V6_ILP32_OFFBIG);
#endif
case _SC_V6_LP64_OFF64:
#if _V6_LP64_OFF64 == 0
if (sizeof(int) * CHAR_BIT == 32 &&
sizeof(long) * CHAR_BIT == 64 &&
sizeof(long) == sizeof(void *) &&
sizeof(void *) == sizeof(off_t))
return 1;
else
return -1;
#else
return (_V6_LP64_OFF64);
#endif
case _SC_V6_LPBIG_OFFBIG:
#if _V6_LPBIG_OFFBIG == 0
if (sizeof(int) * CHAR_BIT >= 32 &&
sizeof(long) * CHAR_BIT >= 64 &&
sizeof(void *) * CHAR_BIT >= 64 &&
sizeof(off_t) * CHAR_BIT >= 64)
return 1;
else
return -1;
#else
return (_V6_LPBIG_OFFBIG);
#endif
case _SC_ATEXIT_MAX:
return (ATEXIT_SIZE);
case _SC_IOV_MAX:
mib[0] = CTL_KERN;
mib[1] = KERN_IOV_MAX;
break;
case _SC_XOPEN_CRYPT:
return (_XOPEN_CRYPT);
case _SC_XOPEN_ENH_I18N:
return (_XOPEN_ENH_I18N);
case _SC_XOPEN_LEGACY:
return (_XOPEN_LEGACY);
case _SC_XOPEN_REALTIME:
#if _XOPEN_REALTIME == 0
sverrno = errno;
value = sysconf(_SC_ASYNCHRONOUS_IO) > 0 &&
sysconf(_SC_MEMLOCK) > 0 &&
sysconf(_SC_MEMLOCK_RANGE) > 0 &&
sysconf(_SC_MESSAGE_PASSING) > 0 &&
sysconf(_SC_PRIORITY_SCHEDULING) > 0 &&
sysconf(_SC_REALTIME_SIGNALS) > 0 &&
sysconf(_SC_SEMAPHORES) > 0 &&
sysconf(_SC_SHARED_MEMORY_OBJECTS) > 0 &&
sysconf(_SC_SYNCHRONIZED_IO) > 0 &&
sysconf(_SC_TIMERS) > 0;
errno = sverrno;
if (value)
return (200112L);
else
return (-1);
#else
return (_XOPEN_REALTIME);
#endif
case _SC_XOPEN_REALTIME_THREADS:
#if _XOPEN_REALTIME_THREADS == 0
#error "_XOPEN_REALTIME_THREADS"
#else
return (_XOPEN_REALTIME_THREADS);
#endif
case _SC_XOPEN_SHM:
len = sizeof(lvalue);
sverrno = errno;
if (sysctlbyname("kern.ipc.shmmin", &lvalue, &len, NULL,
0) == -1) {
errno = sverrno;
return (-1);
}
errno = sverrno;
return (1);
case _SC_XOPEN_STREAMS:
return (_XOPEN_STREAMS);
case _SC_XOPEN_UNIX:
return (_XOPEN_UNIX);
#ifdef _XOPEN_VERSION
case _SC_XOPEN_VERSION:
return (_XOPEN_VERSION);
#endif
#ifdef _XOPEN_XCU_VERSION
case _SC_XOPEN_XCU_VERSION:
return (_XOPEN_XCU_VERSION);
#endif
case _SC_SYMLOOP_MAX:
return (MAXSYMLINKS);
case _SC_RAW_SOCKETS:
return (_POSIX_RAW_SOCKETS);
case _SC_IPV6:
#if _POSIX_IPV6 == 0
sverrno = errno;
value = _socket(PF_INET6, SOCK_DGRAM, 0);
errno = sverrno;
if (value >= 0) {
_close(value);
return (200112L);
} else
return (0);
#else
return (_POSIX_IPV6);
#endif
case _SC_NPROCESSORS_CONF:
case _SC_NPROCESSORS_ONLN:
if (_elf_aux_info(AT_NCPUS, &value, sizeof(value)) == 0)
return ((long)value);
mib[0] = CTL_HW;
mib[1] = HW_NCPU;
break;
#ifdef _SC_PHYS_PAGES
case _SC_PHYS_PAGES:
len = sizeof(lvalue);
if (sysctlbyname("hw.availpages", &lvalue, &len, NULL, 0) == -1)
return (-1);
return (lvalue);
#endif
#ifdef _SC_CPUSET_SIZE
case _SC_CPUSET_SIZE:
len = sizeof(value);
if (sysctlbyname("kern.sched.cpusetsize", &value, &len, NULL,
0) == -1)
return (-1);
return ((long)value);
#endif
default:
errno = EINVAL;
return (-1);
}
len = sizeof(value);
if (sysctl(mib, 2, &value, &len, NULL, 0) == -1)
value = -1;
return ((long)value);
}