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android / platform / bionic / 61ff834 / . / libc / unistd / sysconf.c
blob: 9377802bd90b06c9e3bd853d3667e4c35197e2f2 [file] [log] [blame]
/*
* Copyright (C) 2008 The Android Open Source Project
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * 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.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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
* COPYRIGHT OWNER 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 <unistd.h>
#include <sys/sysconf.h>
#include <limits.h>
#include <bionic_tls.h>
#include <asm/page.h>
#include <stdio.h> /* for FOPEN_MAX */
#include <errno.h>
#include <fcntl.h>
#include <string.h>
#include <ctype.h>
/* seems to be the default on Linux, per the GLibc sources and my own digging */
#define SYSTEM_CLK_TCK 100
#define SYSTEM_IOV_MAX 1024
#define SYSTEM_DELAYTIMER_MAX 2147483647
#define SYSTEM_MQ_OPEN_MAX 8
#define SYSTEM_MQ_PRIO_MAX 32768
#define SYSTEM_SEM_NSEMS_MAX 256
#define SYSTEM_SEM_VALUE_MAX 0x3fffffff /* see bionic/semaphore.c */
#define SYSTEM_SIGQUEUE_MAX 32
#define SYSTEM_TIMER_MAX 32
#define SYSTEM_LOGIN_NAME_MAX 256
#define SYSTEM_TTY_NAME_MAX 32
/* the following depends on our implementation */
#define SYSTEM_ATEXIT_MAX 65536 /* our implementation is unlimited */
#define SYSTEM_THREAD_KEYS_MAX BIONIC_TLS_SLOTS
#define SYSTEM_THREAD_STACK_MIN 32768 /* lower values may be possible, but be conservative */
#define SYSTEM_THREAD_THREADS_MAX 2048 /* really unlimited */
#define SYSTEM_2_C_BIND _POSIX_VERSION /* Posix C binding version */
#define SYSTEM_2_C_VER _POSIX2_C_VERSION
#define SYSTEM_2_C_DEV -1 /* Posix C development tools unsupported on the device */
#define SYSTEM_2_FORT_DEV -1 /* Fortran development unsupported */
#define SYSTEM_2_FORT_RUN -1 /* Fortran runtime unsupported */
#define SYSTEM_2_SW_DEV -1 /* posix software dev utilities unsupported */
#define SYSTEM_2_LOCALEDEF -1 /* localdef() unimplemented */
#define SYSTEM_2_UPE -1 /* No UPE for you ! (User Portability Utilities) */
#define SYSTEM_2_VERSION -1 /* No posix command-line tools */
static int __get_nproc_conf(void);
static int __get_nproc_onln(void);
static int __get_phys_pages(void);
static int __get_avphys_pages(void);
int
sysconf( int name )
{
switch (name) {
#ifdef _POSIX_ARG_MAX
case _SC_ARG_MAX: return _POSIX_ARG_MAX;
#endif
#ifdef _POSIX2_BC_BASE_MAX
case _SC_BC_BASE_MAX: return _POSIX2_BC_BASE_MAX;
#endif
#ifdef _POSIX2_BC_DIM_MAX
case _SC_BC_DIM_MAX: return _POSIX2_BC_DIM_MAX;
#endif
#ifdef _POSIX2_BC_SCALE_MAX
case _SC_BC_SCALE_MAX: return _POSIX2_BC_SCALE_MAX;
#endif
#ifdef _POSIX2_BC_STRING_MAX
case _SC_BC_STRING_MAX: return _POSIX2_BC_STRING_MAX;
#endif
case _SC_CHILD_MAX: return CHILD_MAX;
case _SC_CLK_TCK: return SYSTEM_CLK_TCK;
#ifdef _POSIX2_COLL_WEIGHTS_MASK
case _SC_COLL_WEIGHTS_MAX: return _POSIX2_COLL_WEIGHTS_MASK;
#endif
#ifdef _POSIX2_EXPR_NEST_MAX
case _SC_EXPR_NEST_MAX: return _POSIX2_EXPR_NEST_MAX;
#endif
#ifdef _POSIX2_LINE_MAX
case _SC_LINE_MAX: return _POSIX2_LINE_MAX;
#endif
case _SC_NGROUPS_MAX: return NGROUPS_MAX;
case _SC_OPEN_MAX: return OPEN_MAX;
//case _SC_PASS_MAX: return PASS_MAX;
case _SC_2_C_BIND: return SYSTEM_2_C_BIND;
case _SC_2_C_DEV: return SYSTEM_2_C_DEV;
case _SC_2_C_VERSION: return SYSTEM_2_C_VER;
//case _SC_2_CHAR_TERM: return ;
case _SC_2_FORT_DEV: return SYSTEM_2_FORT_DEV;
case _SC_2_FORT_RUN: return SYSTEM_2_FORT_RUN;
case _SC_2_LOCALEDEF: return SYSTEM_2_LOCALEDEF;
case _SC_2_SW_DEV: return SYSTEM_2_SW_DEV;
case _SC_2_UPE: return SYSTEM_2_UPE;
case _SC_2_VERSION: return SYSTEM_2_VERSION;
#ifdef _POSIX_JOB_CONTROL
case _SC_JOB_CONTROL: return _POSIX_JOB_CONTROL;
#endif
#ifdef _POSIX_SAVED_IDS
case _SC_SAVED_IDS: return _POSIX_SAVED_IDS;
#endif
#ifdef _POSIX_VERSION
case _SC_VERSION: return _POSIX_VERSION;
#endif
//case _SC_RE_DUP_<AX: return ;
case _SC_STREAM_MAX: return FOPEN_MAX;
//case _SC_TZNAME_MAX: return ;
#if _XOPEN_CRYPT
case _SC_XOPEN_CRYPT: return _XOPEN_CRYPT;
#endif
#ifdef _XOPEN_ENH_I18N
case _SC_XOPEN_ENH_I18N: return _XOPEN_ENH_I18N;
#endif
#ifdef _XOPEN_SHM
case _SC_XOPEN_SHM: return _XOPEN_SHM;
#endif
#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
#ifdef _XOPEN_REALTIME
case _SC_XOPEN_REALTIME: return _XOPEN_REALTIME;
#endif
#ifdef _XOPEN_REALTIME_THREADS
case _SC_XOPEN_REALTIME_THREADS: return _XOPEN_REALTIME_THREADS;
#endif
#ifdef _XOPEN_LEGACY
case _SC_XOPEN_LEGACY: return _XOPEN_LEGACY;
#endif
case _SC_ATEXIT_MAX: return SYSTEM_ATEXIT_MAX;
case _SC_IOV_MAX: return SYSTEM_IOV_MAX;
case _SC_PAGESIZE: return PAGE_SIZE;
case _SC_PAGE_SIZE: return PAGE_SIZE;
#ifdef _XOPEN_UNIX
case _SC_XOPEN_UNIX: return _XOPEN_UNIX;
#endif
// XXX: TODO: XBS5 nonsense
#ifdef AIO_LISTIO_MAX
case _SC_AIO_LISTIO_MAX: return AIO_LISTIO_MAX;
#endif
#ifdef AIO_MAX
case _SC_AIO_MAX: return AIO_MAX;
#endif
#ifdef AIO_PRIO_DELTA_MAX
case _SC_AIO_PRIO_DELTA_MAX: return AIO_PRIO_DELTA_MAX;
#endif
case _SC_DELAYTIMER_MAX: return SYSTEM_DELAYTIMER_MAX;
case _SC_MQ_OPEN_MAX: return SYSTEM_MQ_OPEN_MAX;
case _SC_MQ_PRIO_MAX: return SYSTEM_MQ_PRIO_MAX;
case _SC_RTSIG_MAX: return RTSIG_MAX;
case _SC_SEM_NSEMS_MAX: return SYSTEM_SEM_NSEMS_MAX;
case _SC_SEM_VALUE_MAX: return SYSTEM_SEM_VALUE_MAX;
case _SC_SIGQUEUE_MAX: return SYSTEM_SIGQUEUE_MAX;
case _SC_TIMER_MAX: return SYSTEM_TIMER_MAX;
#ifdef _POSIX_ASYNCHRONOUS_IO
case _SC_ASYNCHRONOUS_IO: return _POSIX_ASYNCHRONOUS_IO;
#endif
#ifdef _POSIX_FSYNC
case _SC_FSYNC: return _POSIX_FSYNC;
#endif
#ifdef _POSIX_MAPPED_FILES
case _SC_MAPPED_FILES: return _POSIX_MAPPED_FILES;
#endif
#ifdef _POSIX_MEMLOCK
case _SC_MEMLOCK: return _POSIX_MEMLOCK;
#endif
#ifdef _POSIX_MEMLOCK_RANGE
case _SC_MEMLOCK_RANGE: return _POSIX_MEMLOCK_RANGE
#endif
#ifdef _POSIX_MEMORY_PROTECTION
case _SC_MEMORY_PROTECTION: return _POSIX_MEMORY_PROTECTION;
#endif
#ifdef _POSIX_MESSAGE_PASSING
case _SC_MESSAGE_PASSING: return _POSIX_MESSAGE_PASSING;
#endif
#ifdef _POSIX_PRIORITIZED_IO
case _SC_PRIORITIZED_IO: return _POSIX_PRIORITIZED_IO;
#endif
#ifdef _POSIX_PRIORITY_SCHEDULING
case _SC_PRIORITY_SCHEDULING: return _POSIX_PRIORITY_SCHEDULING;
#endif
#ifdef _POSIX_REALTIME_SIGNALS
case _SC_REALTIME_SIGNALS: return _POSIX_REALTIME_SIGNALS;
#endif
#ifdef _POSIX_SEMAPHORES
case _SC_SEMAPHORES: return _POSIX_SEMAPHORES;
#endif
#ifdef _POSIX_SHARED_MEMORY_OBJECTS
case _SC_SHARED_MEMORY_OBJECTS: return _POSIX_SHARED_MEMORY_OBJECTS;
#endif
#ifdef _POSIX_SYNCHRONIZED_IO
case _SC_SYNCHRONIZED_IO: return _POSIX_SYNCHRONIZED_IO;
#endif
#ifdef _POSIX_TIMERS
case _SC_TIMERS: return _POSIX_TIMERS;
#endif
// GETGR_R_SIZE_MAX ?
// GETPW_R_SIZE_MAX ?
case _SC_LOGIN_NAME_MAX: return SYSTEM_LOGIN_NAME_MAX;
#ifdef _POSIX_THREAD_DESTRUCTOR_ITERATIONS
case _SC_THREAD_DESTRUCTOR_ITERATIONS: return _POSIX_THREAD_DESTRUCTOR_ITERATIONS;
#endif
case _SC_THREAD_KEYS_MAX: return SYSTEM_THREAD_KEYS_MAX;
case _SC_THREAD_STACK_MIN: return SYSTEM_THREAD_STACK_MIN;
case _SC_THREAD_THREADS_MAX: return SYSTEM_THREAD_THREADS_MAX;
case _SC_TTY_NAME_MAX: return SYSTEM_TTY_NAME_MAX;
#ifdef _POSIX_THREADS
case _SC_THREADS: return _POSIX_THREADS;
#endif
#ifdef _POSIX_THREAD_ATTR_STACKADDR
case _SC_THREAD_ATTR_STACKADDR: return _POSIX_THREAD_ATTR_STACKADDR;
#endif
#ifdef _POSIX_THREAD_ATTR_STACKSIZE
case _SC_THREAD_ATTR_STACKSIZE: return _POSIX_THREAD_ATTR_STACKSIZE;
#endif
#ifdef _POSIX_THREAD_PRIORITY_SCHEDULING
case _SC_THREAD_PRIORITY_SCHEDULING: return _POSIX_THREAD_PRIORITY_SCHEDULING;
#endif
#ifdef _POSIX_THREAD_PRIO_INHERIT
case _SC_THREAD_PRIO_INHERIT: return _POSIX_THREAD_PRIO_INHERIT;
#endif
#ifdef _POSIX_THREAD_PRIO_PROTECT
case _SC_THREAD_PRIO_PROTECT: return _POSIX_THREAD_PRIO_PROTECT;
#endif
#ifdef _POSIX_THREAD_SAFE_FUNCTIONS
case _SC_THREAD_SAFE_FUNCTIONS: return _POSIX_THREAD_SAFE_FUNCTIONS
#endif
case _SC_NPROCESSORS_CONF: return __get_nproc_conf();
case _SC_NPROCESSORS_ONLN: return __get_nproc_onln();
case _SC_PHYS_PAGES: return __get_phys_pages();
case _SC_AVPHYS_PAGES: return __get_avphys_pages();
default:
/* Posix says EINVAL is the only error that shall be returned,
* but GLibc uses ENOSYS */
errno = ENOSYS;
return -1;
}
}
typedef struct {
int rpos;
int len;
int overflow;
int fd;
int in_len;
int in_pos;
char buff[128];
char input[128];
} LineParser;
static int
line_parser_init( LineParser* p, const char* path )
{
p->rpos = 0;
p->len = (int)sizeof(p->buff);
p->overflow = 0;
p->in_len = 0;
p->in_pos = 0;
p->fd = open( path, O_RDONLY );
return p->fd;
}
static int
line_parser_addc( LineParser* p, int c )
{
if (p->overflow) {
p->overflow = (c == '\n');
return 0;
}
if (p->rpos >= p->len) {
p->overflow = 1;
return 0;
}
if (c == '\n') {
p->buff[p->rpos] = 0;
p->rpos = 0;
return 1;
}
p->buff[p->rpos++] = (char) c;
return 0;
}
static int
line_parser_getc( LineParser* p )
{
if (p->in_pos >= p->in_len) {
int ret;
p->in_len = p->in_pos = 0;
do {
ret = read(p->fd, p->input, sizeof(p->input));
} while (ret < 0 && errno == EINTR);
if (ret <= 0)
return -1;
p->in_len = ret;
}
return p->input[ p->in_pos++ ];
}
static const char*
line_parser_gets( LineParser* p )
{
for (;;) {
for (;;) {
int c = line_parser_getc(p);
if (c < 0) {
close(p->fd);
p->fd = -1;
return NULL;
}
if (line_parser_addc(p, c))
return p->buff;
}
}
}
static void
line_parser_done( LineParser* p )
{
if (p->fd >= 0) {
close(p->fd);
p->fd = -1;
}
}
static int
__get_nproc_conf(void)
{
LineParser parser[1];
const char* p;
int count = 0;
if (line_parser_init(parser, "/proc/cpuinfo") < 0)
return 1;
while ((p = line_parser_gets(parser))) {
if ( !memcmp(p, "processor", 9) )
count += 1;
}
return (count < 1) ? 1 : count;
}
static int
__get_nproc_onln(void)
{
LineParser parser[1];
const char* p;
int count = 0;
if (line_parser_init(parser, "/proc/stat") < 0)
return 1;
while ((p = line_parser_gets(parser))) {
if ( !memcmp(p, "cpu", 3) && isdigit(p[3]) )
count += 1;
}
return (count < 1) ? 1 : count;
}
static int
__get_phys_pages(void)
{
LineParser parser[1];
const char* p;
if (line_parser_init(parser, "/proc/meminfo") < 0)
return -2; /* what ? */
while ((p = line_parser_gets(parser))) {
long total;
if ( sscanf(p, "MemTotal: %ld kB", &total) == 1 ) {
line_parser_done(parser);
return (int) (total / (PAGE_SIZE/1024));
}
}
return -3;
}
static int
__get_avphys_pages(void)
{
LineParser parser[1];
const char* p;
if (line_parser_init(parser, "/proc/meminfo") < 0)
return -1; /* what ? */
while ((p = line_parser_gets(parser))) {
long total;
if ( sscanf(p, "MemFree: %ld kB", &total) == 1 ) {
line_parser_done(parser);
return (int) (total / (PAGE_SIZE/1024));
}
}
return -1;
}