f1ed349dd9
here is the reason: 1.clock_systime_timespec(core function) always exist regardless the setting 2.CLOCK_MONOTONIC is a foundamental clock type required by many places Signed-off-by: Xiang Xiao <xiaoxiang@xiaomi.com>
249 lines
12 KiB
C
249 lines
12 KiB
C
/****************************************************************************
|
|
* libs/libc/unistd/lib_sysconf.c
|
|
*
|
|
* Licensed to the Apache Software Foundation (ASF) under one or more
|
|
* contributor license agreements. See the NOTICE file distributed with
|
|
* this work for additional information regarding copyright ownership. The
|
|
* ASF licenses this file to you under the Apache License, Version 2.0 (the
|
|
* "License"); you may not use this file except in compliance with the
|
|
* License. You may obtain a copy of the License at
|
|
*
|
|
* http://www.apache.org/licenses/LICENSE-2.0
|
|
*
|
|
* Unless required by applicable law or agreed to in writing, software
|
|
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
|
|
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
|
|
* License for the specific language governing permissions and limitations
|
|
* under the License.
|
|
*
|
|
****************************************************************************/
|
|
|
|
/****************************************************************************
|
|
* Included Files
|
|
****************************************************************************/
|
|
|
|
#include <nuttx/config.h>
|
|
|
|
#include <unistd.h>
|
|
#include <sched.h>
|
|
#include <errno.h>
|
|
|
|
/****************************************************************************
|
|
* Public Functions
|
|
****************************************************************************/
|
|
|
|
/****************************************************************************
|
|
* Name: sysconf
|
|
*
|
|
* Description:
|
|
* The sysconf() function provides a method for the application to
|
|
* determine the current value of a configurable system limit or option
|
|
* (variable). The implementation will support all of the variables
|
|
* listed in the following table and may support others.
|
|
*
|
|
* The 'name' argument represents the system variable to be queried. The
|
|
* following table lists the minimal set of system variables from
|
|
* <limits.h> or <unistd.h> that can be returned by sysconf(), and the
|
|
* symbolic constants defined in <unistd.h> that are the corresponding
|
|
* values used for name.
|
|
*
|
|
* Variable Value of Name
|
|
*
|
|
* {AIO_LISTIO_MAX} _SC_AIO_LISTIO_MAX
|
|
* {AIO_MAX} _SC_AIO_MAX
|
|
* {AIO_PRIO_DELTA_MAX} _SC_AIO_PRIO_DELTA_MAX
|
|
* {ARG_MAX} _SC_ARG_MAX
|
|
* {ATEXIT_MAX} _SC_ATEXIT_MAX
|
|
* {BC_BASE_MAX} _SC_BC_BASE_MAX
|
|
* {BC_DIM_MAX} _SC_BC_DIM_MAX
|
|
* {BC_SCALE_MAX} _SC_BC_SCALE_MAX
|
|
* {BC_STRING_MAX} _SC_BC_STRING_MAX
|
|
* {CHILD_MAX} _SC_CHILD_MAX
|
|
* Clock ticks/second _SC_CLK_TCK
|
|
* {COLL_WEIGHTS_MAX} _SC_COLL_WEIGHTS_MAX
|
|
* {DELAYTIMER_MAX} _SC_DELAYTIMER_MAX
|
|
* {EXPR_NEST_MAX} _SC_EXPR_NEST_MAX
|
|
* {HOST_NAME_MAX} _SC_HOST_NAME_MAX
|
|
* {IOV_MAX} _SC_IOV_MAX
|
|
* {LINE_MAX} _SC_LINE_MAX
|
|
* {LOGIN_NAME_MAX} _SC_LOGIN_NAME_MAX
|
|
* {NGROUPS_MAX} _SC_NGROUPS_MAX
|
|
* Maximum size of getgrgid_r() and _SC_GETGR_R_SIZE_MAX
|
|
* getgrnam_r() data buffers
|
|
* Maximum size of getpwuid_r() and _SC_GETPW_R_SIZE_MAX
|
|
* getpwnam_r() data buffers
|
|
* {MQ_OPEN_MAX} _SC_MQ_OPEN_MAX
|
|
* {MQ_PRIO_MAX} _SC_MQ_PRIO_MAX
|
|
* {OPEN_MAX} _SC_OPEN_MAX
|
|
* _POSIX_ADVISORY_INFO _SC_ADVISORY_INFO
|
|
* _POSIX_BARRIERS _SC_BARRIERS
|
|
* _POSIX_ASYNCHRONOUS_IO _SC_ASYNCHRONOUS_IO
|
|
* _POSIX_CLOCK_SELECTION _SC_CLOCK_SELECTION
|
|
* _POSIX_CPUTIME _SC_CPUTIME
|
|
* _POSIX_FSYNC _SC_FSYNC
|
|
* _POSIX_IPV6 _SC_IPV6
|
|
* _POSIX_JOB_CONTROL _SC_JOB_CONTROL
|
|
* _POSIX_MAPPED_FILES _SC_MAPPED_FILES
|
|
* _POSIX_MEMLOCK _SC_MEMLOCK
|
|
* _POSIX_MEMLOCK_RANGE _SC_MEMLOCK_RANGE
|
|
* _POSIX_MEMORY_PROTECTION _SC_MEMORY_PROTECTION
|
|
* _POSIX_MESSAGE_PASSING _SC_MESSAGE_PASSING
|
|
* _POSIX_MONOTONIC_CLOCK _SC_MONOTONIC_CLOCK
|
|
* _POSIX_PRIORITIZED_IO _SC_PRIORITIZED_IO
|
|
* _POSIX_PRIORITY_SCHEDULING _SC_PRIORITY_SCHEDULING
|
|
* _POSIX_RAW_SOCKETS _SC_RAW_SOCKETS
|
|
* _POSIX_READER_WRITER_LOCKS _SC_READER_WRITER_LOCKS
|
|
* _POSIX_REALTIME_SIGNALS _SC_REALTIME_SIGNALS
|
|
* _POSIX_REGEXP _SC_REGEXP
|
|
* _POSIX_SAVED_IDS _SC_SAVED_IDS
|
|
* _POSIX_SEMAPHORES _SC_SEMAPHORES
|
|
* _POSIX_SHARED_MEMORY_OBJECTS _SC_SHARED_MEMORY_OBJECTS
|
|
* _POSIX_SHELL _SC_SHELL
|
|
* _POSIX_SPAWN _SC_SPAWN
|
|
* _POSIX_SPIN_LOCKS _SC_SPIN_LOCKS
|
|
* _POSIX_SPORADIC_SERVER _SC_SPORADIC_SERVER
|
|
* _POSIX_SS_REPL_MAX _SC_SS_REPL_MAX
|
|
* _POSIX_SYNCHRONIZED_IO _SC_SYNCHRONIZED_IO
|
|
* _POSIX_THREAD_ATTR_STACKADDR _SC_THREAD_ATTR_STACKADDR
|
|
* _POSIX_THREAD_ATTR_STACKSIZE _SC_THREAD_ATTR_STACKSIZE
|
|
* _POSIX_THREAD_CPUTIME _SC_THREAD_CPUTIME
|
|
* _POSIX_THREAD_PRIO_INHERIT _SC_THREAD_PRIO_INHERIT
|
|
* _POSIX_THREAD_PRIO_PROTECT _SC_THREAD_PRIO_PROTECT
|
|
* _POSIX_THREAD_PRIORITY_SCHEDULING _SC_THREAD_PRIORITY_SCHEDULING
|
|
* _POSIX_THREAD_PROCESS_SHARED _SC_THREAD_PROCESS_SHARED
|
|
* _POSIX_THREAD_SAFE_FUNCTIONS _SC_THREAD_SAFE_FUNCTIONS
|
|
* _POSIX_THREAD_SPORADIC_SERVER _SC_THREAD_SPORADIC_SERVER
|
|
* _POSIX_THREADS _SC_THREADS
|
|
* _POSIX_TIMEOUTS _SC_TIMEOUTS
|
|
* _POSIX_TIMERS _SC_TIMERS
|
|
* _POSIX_TRACE _SC_TRACE
|
|
* _POSIX_TRACE_EVENT_FILTER _SC_TRACE_EVENT_FILTER
|
|
* _POSIX_TRACE_EVENT_NAME_MAX _SC_TRACE_EVENT_NAME_MAX
|
|
* _POSIX_TRACE_INHERIT _SC_TRACE_INHERIT
|
|
* _POSIX_TRACE_LOG _SC_TRACE_LOG
|
|
* _POSIX_TRACE_NAME_MAX _SC_TRACE_NAME_MAX
|
|
* _POSIX_TRACE_SYS_MAX _SC_TRACE_SYS_MAX
|
|
* _POSIX_TRACE_USER_EVENT_MAX _SC_TRACE_USER_EVENT_MAX
|
|
* _POSIX_TYPED_MEMORY_OBJECTS _SC_TYPED_MEMORY_OBJECTS
|
|
* _POSIX_VERSION _SC_VERSION
|
|
* _POSIX_V6_ILP32_OFF32 _SC_V6_ILP32_OFF32
|
|
* _POSIX_V6_ILP32_OFFBIG _SC_V6_ILP32_OFFBIG
|
|
* _POSIX_V6_LP64_OFF64 _SC_V6_LP64_OFF64
|
|
* _POSIX_V6_LPBIG_OFFBIG _SC_V6_LPBIG_OFFBIG
|
|
* _POSIX2_C_BIND _SC_2_C_BIND
|
|
* _POSIX2_C_DEV _SC_2_C_DEV
|
|
* _POSIX2_CHAR_TERM _SC_2_CHAR_TERM
|
|
* _POSIX2_FORT_DEV _SC_2_FORT_DEV
|
|
* _POSIX2_FORT_RUN _SC_2_FORT_RUN
|
|
* _POSIX2_LOCALEDEF _SC_2_LOCALEDEF
|
|
* _POSIX2_PBS _SC_2_PBS
|
|
* _POSIX2_PBS_ACCOUNTING _SC_2_PBS_ACCOUNTING
|
|
* _POSIX2_PBS_CHECKPOINT _SC_2_PBS_CHECKPOINT
|
|
* _POSIX2_PBS_LOCATE _SC_2_PBS_LOCATE
|
|
* _POSIX2_PBS_MESSAGE _SC_2_PBS_MESSAGE
|
|
* _POSIX2_PBS_TRACK _SC_2_PBS_TRACK
|
|
* _POSIX2_SW_DEV _SC_2_SW_DEV
|
|
* _POSIX2_UPE _SC_2_UPE
|
|
* _POSIX2_VERSION _SC_2_VERSION
|
|
* {PAGE_SIZE} _SC_PAGE_SIZE
|
|
* {PAGESIZE} _SC_PAGESIZE
|
|
* {PTHREAD_DESTRUCTOR_ITERATIONS} _SC_THREAD_DESTRUCTOR_ITERATIONS
|
|
* {PTHREAD_KEYS_MAX} _SC_THREAD_KEYS_MAX
|
|
* {PTHREAD_STACK_MIN} _SC_THREAD_STACK_MIN
|
|
* {PTHREAD_THREADS_MAX} _SC_THREAD_THREADS_MAX
|
|
* {RE_DUP_MAX} _SC_RE_DUP_MAX
|
|
* {RTSIG_MAX} _SC_RTSIG_MAX
|
|
* {SEM_NSEMS_MAX} _SC_SEM_NSEMS_MAX
|
|
* {SEM_VALUE_MAX} _SC_SEM_VALUE_MAX
|
|
* {SIGQUEUE_MAX} _SC_SIGQUEUE_MAX
|
|
* {STREAM_MAX} _SC_STREAM_MAX
|
|
* {SYMLOOP_MAX} _SC_SYMLOOP_MAX
|
|
* {TIMER_MAX} _SC_TIMER_MAX
|
|
* {TTY_NAME_MAX} _SC_TTY_NAME_MAX
|
|
* {TZNAME_MAX} _SC_TZNAME_MAX
|
|
* _XBS5_ILP32_OFF32 (LEGACY) _SC_XBS5_ILP32_OFF32 (LEGACY)
|
|
* _XBS5_ILP32_OFFBIG (LEGACY) _SC_XBS5_ILP32_OFFBIG (LEGACY)
|
|
* _XBS5_LP64_OFF64 (LEGACY) _SC_XBS5_LP64_OFF64 (LEGACY)
|
|
* _XBS5_LPBIG_OFFBIG (LEGACY) _SC_XBS5_LPBIG_OFFBIG (LEGACY)
|
|
* _XOPEN_CRYPT _SC_XOPEN_CRYPT
|
|
* _XOPEN_ENH_I18N _SC_XOPEN_ENH_I18N
|
|
* _XOPEN_LEGACY _SC_XOPEN_LEGACY
|
|
* _XOPEN_REALTIME _SC_XOPEN_REALTIME
|
|
* _XOPEN_REALTIME_THREADS _SC_XOPEN_REALTIME_THREADS
|
|
* _XOPEN_SHM _SC_XOPEN_SHM
|
|
* _XOPEN_STREAMS _SC_XOPEN_STREAMS
|
|
* _XOPEN_UNIX _SC_XOPEN_UNIX
|
|
* _XOPEN_VERSION _SC_XOPEN_VERSION
|
|
*
|
|
* Returned Value:
|
|
* If name is an invalid value, sysconf() will return -1 and set errno to
|
|
* EINVAL to indicate the error. If the variable corresponding to name has
|
|
* no limit, sysconf() will return -1 without changing the value of errno.
|
|
* Note that indefinite limits do not imply infinite limits; see
|
|
* <limits.h>.
|
|
*
|
|
* Otherwise, sysconf() will return the current variable value on the
|
|
* system. The value returned will not be more restrictive than the
|
|
* corresponding value described to the application when it was compiled
|
|
* with the implementation's <limits.h> or <unistd.h>. The value will not
|
|
* change during the lifetime of the calling process, except that
|
|
* sysconf(_SC_OPEN_MAX) may return different values before and after a
|
|
* call to setrlimit() which changes the RLIMIT_NOFILE soft limit.
|
|
*
|
|
* If the variable corresponding to name is dependent on an unsupported
|
|
* option, the results are unspecified.
|
|
*
|
|
****************************************************************************/
|
|
|
|
long sysconf(int name)
|
|
{
|
|
int errcode;
|
|
|
|
/* NOTE: The initialize implementation of this interface is very sparse.
|
|
* It was originally created to support only the functionality of
|
|
* getdtablesize() but can be extended to support as much of the standard
|
|
* POSIX sysconf() as is necessary.
|
|
*/
|
|
|
|
switch (name)
|
|
{
|
|
case _SC_CLK_TCK:
|
|
return CLOCKS_PER_SEC;
|
|
|
|
case _SC_OPEN_MAX:
|
|
return _POSIX_OPEN_MAX;
|
|
|
|
case _SC_ATEXIT_MAX:
|
|
#ifdef CONFIG_SCHED_EXIT_MAX
|
|
return CONFIG_SCHED_EXIT_MAX;
|
|
#else
|
|
return 0;
|
|
#endif
|
|
|
|
case _SC_NPROCESSORS_CONF:
|
|
case _SC_NPROCESSORS_ONLN:
|
|
return CONFIG_SMP_NCPUS;
|
|
|
|
case _SC_MONOTONIC_CLOCK:
|
|
return 1;
|
|
|
|
case _SC_PAGESIZE:
|
|
#ifdef CONFIG_MM_PGSIZE
|
|
return CONFIG_MM_PGSIZE;
|
|
#else
|
|
return 1;
|
|
#endif
|
|
|
|
default:
|
|
#if 0 /* Assume valid but not implemented for the time being */
|
|
errcode = EINVAL;
|
|
#else
|
|
errcode = ENOSYS;
|
|
#endif
|
|
break;
|
|
}
|
|
|
|
set_errno(errcode);
|
|
return ERROR;
|
|
}
|