|  | /* | 
|  | * 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 <asm/page.h> | 
|  | #include <bionic_tls.h> | 
|  | #include <ctype.h> | 
|  | #include <dirent.h> | 
|  | #include <errno.h> | 
|  | #include <fcntl.h> | 
|  | #include <limits.h> | 
|  | #include <pthread.h> | 
|  | #include <stdio.h>  // For FOPEN_MAX. | 
|  | #include <string.h> | 
|  | #include <sys/sysconf.h> | 
|  | #include <time.h> | 
|  | #include <unistd.h> | 
|  |  | 
|  | #include "private/ScopedReaddir.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_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       /* localedef() unimplemented */ | 
|  | #define  SYSTEM_2_UPE        -1       /* No UPE for you ! (User Portability Utilities) */ | 
|  | #define  SYSTEM_2_VERSION    -1       /* No posix command-line tools */ | 
|  |  | 
|  | static bool __matches_cpuN(const char* s) { | 
|  | // The %c trick is to ensure that we have the anchored match "^cpu[0-9]+$". | 
|  | unsigned cpu; | 
|  | char dummy; | 
|  | return (sscanf(s, "cpu%u%c", &cpu, &dummy) == 1); | 
|  | } | 
|  |  | 
|  | static int __sysconf_nprocessors_conf() { | 
|  | // On x86 kernels you can use /proc/cpuinfo for this, but on ARM kernels offline CPUs disappear | 
|  | // from there. This method works on both. | 
|  | ScopedReaddir reader("/sys/devices/system/cpu"); | 
|  | if (reader.IsBad()) { | 
|  | return 1; | 
|  | } | 
|  |  | 
|  | int result = 0; | 
|  | dirent* entry; | 
|  | while ((entry = reader.ReadEntry()) != NULL) { | 
|  | if (entry->d_type == DT_DIR && __matches_cpuN(entry->d_name)) { | 
|  | ++result; | 
|  | } | 
|  | } | 
|  | return result; | 
|  | } | 
|  |  | 
|  | static int __sysconf_nprocessors_onln() { | 
|  | FILE* fp = fopen("/proc/stat", "r"); | 
|  | if (fp == NULL) { | 
|  | return 1; | 
|  | } | 
|  |  | 
|  | int result = 0; | 
|  | char buf[256]; | 
|  | while (fgets(buf, sizeof(buf), fp) != NULL) { | 
|  | // Extract just the first word from the line. | 
|  | // 'cpu0 7976751 1364388 3116842 469770388 8629405 0 49047 0 0 0' | 
|  | char* p = strchr(buf, ' '); | 
|  | if (p != NULL) { | 
|  | *p = 0; | 
|  | } | 
|  | if (__matches_cpuN(buf)) { | 
|  | ++result; | 
|  | } | 
|  | } | 
|  | fclose(fp); | 
|  | return result; | 
|  | } | 
|  |  | 
|  | static int __get_meminfo(const char* pattern) { | 
|  | FILE* fp = fopen("/proc/meminfo", "r"); | 
|  | if (fp == NULL) { | 
|  | return -1; | 
|  | } | 
|  |  | 
|  | int result = -1; | 
|  | char buf[256]; | 
|  | while (fgets(buf, sizeof(buf), fp) != NULL) { | 
|  | long total; | 
|  | if (sscanf(buf, pattern, &total) == 1) { | 
|  | result = (int) (total / (PAGE_SIZE/1024)); | 
|  | break; | 
|  | } | 
|  | } | 
|  | fclose(fp); | 
|  | return result; | 
|  | } | 
|  |  | 
|  | static int __sysconf_phys_pages() { | 
|  | return __get_meminfo("MemTotal: %ld kB"); | 
|  | } | 
|  |  | 
|  | static int __sysconf_avphys_pages() { | 
|  | return __get_meminfo("MemFree: %ld kB"); | 
|  | } | 
|  |  | 
|  | static int __sysconf_monotonic_clock() { | 
|  | timespec t; | 
|  | int rc = clock_getres(CLOCK_MONOTONIC, &t); | 
|  | return (rc == -1) ? -1 : _POSIX_VERSION; | 
|  | } | 
|  |  | 
|  | 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 | 
|  |  | 
|  | case _SC_GETGR_R_SIZE_MAX: return 1024; | 
|  | case _SC_GETPW_R_SIZE_MAX: return 1024; | 
|  |  | 
|  | case _SC_LOGIN_NAME_MAX:    return SYSTEM_LOGIN_NAME_MAX; | 
|  |  | 
|  | case _SC_THREAD_DESTRUCTOR_ITERATIONS: | 
|  | return _POSIX_THREAD_DESTRUCTOR_ITERATIONS; | 
|  |  | 
|  | case _SC_THREAD_KEYS_MAX: | 
|  | return (BIONIC_TLS_SLOTS - TLS_SLOT_FIRST_USER_SLOT - GLOBAL_INIT_THREAD_LOCAL_BUFFER_COUNT); | 
|  |  | 
|  | case _SC_THREAD_STACK_MIN:    return PTHREAD_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_MONOTONIC_CLOCK:   return __sysconf_monotonic_clock(); | 
|  | case _SC_NPROCESSORS_CONF:  return __sysconf_nprocessors_conf(); | 
|  | case _SC_NPROCESSORS_ONLN:  return __sysconf_nprocessors_onln(); | 
|  | case _SC_PHYS_PAGES:        return __sysconf_phys_pages(); | 
|  | case _SC_AVPHYS_PAGES:      return __sysconf_avphys_pages(); | 
|  |  | 
|  | default: | 
|  | /* Posix says EINVAL is the only error that shall be returned, | 
|  | * but GLibc uses ENOSYS */ | 
|  | errno = ENOSYS; | 
|  | return -1; | 
|  | } | 
|  | } |