1 /* 2 * Copyright (C) 2008 The Android Open Source Project 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * * Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * * Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in 12 * the documentation and/or other materials provided with the 13 * distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 16 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 17 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 18 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 19 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 21 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS 22 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 23 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 24 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 25 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28 29 #include <asm/page.h> 30 #include <bionic_tls.h> 31 #include <ctype.h> 32 #include <dirent.h> 33 #include <errno.h> 34 #include <fcntl.h> 35 #include <limits.h> 36 #include <pthread.h> 37 #include <stdio.h> // For FOPEN_MAX. 38 #include <string.h> 39 #include <sys/sysconf.h> 40 #include <time.h> 41 #include <unistd.h> 42 43 #include "private/ScopedReaddir.h" 44 45 /* seems to be the default on Linux, per the GLibc sources and my own digging */ 46 47 #define SYSTEM_CLK_TCK 100 48 #define SYSTEM_IOV_MAX 1024 49 #define SYSTEM_DELAYTIMER_MAX 2147483647 50 #define SYSTEM_MQ_OPEN_MAX 8 51 #define SYSTEM_MQ_PRIO_MAX 32768 52 #define SYSTEM_SEM_NSEMS_MAX 256 53 #define SYSTEM_SEM_VALUE_MAX 0x3fffffff /* see bionic/semaphore.c */ 54 #define SYSTEM_SIGQUEUE_MAX 32 55 #define SYSTEM_TIMER_MAX 32 56 #define SYSTEM_LOGIN_NAME_MAX 256 57 #define SYSTEM_TTY_NAME_MAX 32 58 59 /* the following depends on our implementation */ 60 #define SYSTEM_ATEXIT_MAX 65536 /* our implementation is unlimited */ 61 #define SYSTEM_THREAD_THREADS_MAX 2048 /* really unlimited */ 62 63 #define SYSTEM_2_C_BIND _POSIX_VERSION /* Posix C binding version */ 64 #define SYSTEM_2_C_VER _POSIX2_C_VERSION 65 #define SYSTEM_2_C_DEV -1 /* Posix C development tools unsupported on the device */ 66 #define SYSTEM_2_FORT_DEV -1 /* Fortran development unsupported */ 67 #define SYSTEM_2_FORT_RUN -1 /* Fortran runtime unsupported */ 68 #define SYSTEM_2_SW_DEV -1 /* posix software dev utilities unsupported */ 69 #define SYSTEM_2_LOCALEDEF -1 /* localedef() unimplemented */ 70 #define SYSTEM_2_UPE -1 /* No UPE for you ! (User Portability Utilities) */ 71 #define SYSTEM_2_VERSION -1 /* No posix command-line tools */ 72 73 static bool __matches_cpuN(const char* s) { 74 // The %c trick is to ensure that we have the anchored match "^cpu[0-9]+$". 75 unsigned cpu; 76 char dummy; 77 return (sscanf(s, "cpu%u%c", &cpu, &dummy) == 1); 78 } 79 80 static int __sysconf_nprocessors_conf() { 81 // On x86 kernels you can use /proc/cpuinfo for this, but on ARM kernels offline CPUs disappear 82 // from there. This method works on both. 83 ScopedReaddir reader("/sys/devices/system/cpu"); 84 if (reader.IsBad()) { 85 return 1; 86 } 87 88 int result = 0; 89 dirent* entry; 90 while ((entry = reader.ReadEntry()) != NULL) { 91 if (entry->d_type == DT_DIR && __matches_cpuN(entry->d_name)) { 92 ++result; 93 } 94 } 95 return result; 96 } 97 98 static int __sysconf_nprocessors_onln() { 99 FILE* fp = fopen("/proc/stat", "r"); 100 if (fp == NULL) { 101 return 1; 102 } 103 104 int result = 0; 105 char buf[256]; 106 while (fgets(buf, sizeof(buf), fp) != NULL) { 107 // Extract just the first word from the line. 108 // 'cpu0 7976751 1364388 3116842 469770388 8629405 0 49047 0 0 0' 109 char* p = strchr(buf, ' '); 110 if (p != NULL) { 111 *p = 0; 112 } 113 if (__matches_cpuN(buf)) { 114 ++result; 115 } 116 } 117 fclose(fp); 118 return result; 119 } 120 121 static int __get_meminfo(const char* pattern) { 122 FILE* fp = fopen("/proc/meminfo", "r"); 123 if (fp == NULL) { 124 return -1; 125 } 126 127 int result = -1; 128 char buf[256]; 129 while (fgets(buf, sizeof(buf), fp) != NULL) { 130 long total; 131 if (sscanf(buf, pattern, &total) == 1) { 132 result = (int) (total / (PAGE_SIZE/1024)); 133 break; 134 } 135 } 136 fclose(fp); 137 return result; 138 } 139 140 static int __sysconf_phys_pages() { 141 return __get_meminfo("MemTotal: %ld kB"); 142 } 143 144 static int __sysconf_avphys_pages() { 145 return __get_meminfo("MemFree: %ld kB"); 146 } 147 148 static int __sysconf_monotonic_clock() { 149 timespec t; 150 int rc = clock_getres(CLOCK_MONOTONIC, &t); 151 return (rc == -1) ? -1 : _POSIX_VERSION; 152 } 153 154 int sysconf(int name) { 155 switch (name) { 156 #ifdef _POSIX_ARG_MAX 157 case _SC_ARG_MAX: return _POSIX_ARG_MAX; 158 #endif 159 #ifdef _POSIX2_BC_BASE_MAX 160 case _SC_BC_BASE_MAX: return _POSIX2_BC_BASE_MAX; 161 #endif 162 #ifdef _POSIX2_BC_DIM_MAX 163 case _SC_BC_DIM_MAX: return _POSIX2_BC_DIM_MAX; 164 #endif 165 #ifdef _POSIX2_BC_SCALE_MAX 166 case _SC_BC_SCALE_MAX: return _POSIX2_BC_SCALE_MAX; 167 #endif 168 #ifdef _POSIX2_BC_STRING_MAX 169 case _SC_BC_STRING_MAX: return _POSIX2_BC_STRING_MAX; 170 #endif 171 case _SC_CHILD_MAX: return CHILD_MAX; 172 case _SC_CLK_TCK: return SYSTEM_CLK_TCK; 173 #ifdef _POSIX2_COLL_WEIGHTS_MASK 174 case _SC_COLL_WEIGHTS_MAX: return _POSIX2_COLL_WEIGHTS_MASK; 175 #endif 176 #ifdef _POSIX2_EXPR_NEST_MAX 177 case _SC_EXPR_NEST_MAX: return _POSIX2_EXPR_NEST_MAX; 178 #endif 179 #ifdef _POSIX2_LINE_MAX 180 case _SC_LINE_MAX: return _POSIX2_LINE_MAX; 181 #endif 182 case _SC_NGROUPS_MAX: return NGROUPS_MAX; 183 case _SC_OPEN_MAX: return OPEN_MAX; 184 //case _SC_PASS_MAX: return PASS_MAX; 185 case _SC_2_C_BIND: return SYSTEM_2_C_BIND; 186 case _SC_2_C_DEV: return SYSTEM_2_C_DEV; 187 case _SC_2_C_VERSION: return SYSTEM_2_C_VER; 188 //case _SC_2_CHAR_TERM: return ; 189 case _SC_2_FORT_DEV: return SYSTEM_2_FORT_DEV; 190 case _SC_2_FORT_RUN: return SYSTEM_2_FORT_RUN; 191 case _SC_2_LOCALEDEF: return SYSTEM_2_LOCALEDEF; 192 case _SC_2_SW_DEV: return SYSTEM_2_SW_DEV; 193 case _SC_2_UPE: return SYSTEM_2_UPE; 194 case _SC_2_VERSION: return SYSTEM_2_VERSION; 195 #ifdef _POSIX_JOB_CONTROL 196 case _SC_JOB_CONTROL: return _POSIX_JOB_CONTROL; 197 #endif 198 #ifdef _POSIX_SAVED_IDS 199 case _SC_SAVED_IDS: return _POSIX_SAVED_IDS; 200 #endif 201 #ifdef _POSIX_VERSION 202 case _SC_VERSION: return _POSIX_VERSION; 203 #endif 204 //case _SC_RE_DUP_<AX: return ; 205 case _SC_STREAM_MAX: return FOPEN_MAX; 206 //case _SC_TZNAME_MAX: return ; 207 #if _XOPEN_CRYPT 208 case _SC_XOPEN_CRYPT: return _XOPEN_CRYPT; 209 #endif 210 #ifdef _XOPEN_ENH_I18N 211 case _SC_XOPEN_ENH_I18N: return _XOPEN_ENH_I18N; 212 #endif 213 #ifdef _XOPEN_SHM 214 case _SC_XOPEN_SHM: return _XOPEN_SHM; 215 #endif 216 #ifdef _XOPEN_VERSION 217 case _SC_XOPEN_VERSION: return _XOPEN_VERSION; 218 #endif 219 #ifdef _XOPEN_XCU_VERSION 220 case _SC_XOPEN_XCU_VERSION: return _XOPEN_XCU_VERSION; 221 #endif 222 #ifdef _XOPEN_REALTIME 223 case _SC_XOPEN_REALTIME: return _XOPEN_REALTIME; 224 #endif 225 #ifdef _XOPEN_REALTIME_THREADS 226 case _SC_XOPEN_REALTIME_THREADS: return _XOPEN_REALTIME_THREADS; 227 #endif 228 #ifdef _XOPEN_LEGACY 229 case _SC_XOPEN_LEGACY: return _XOPEN_LEGACY; 230 #endif 231 case _SC_ATEXIT_MAX: return SYSTEM_ATEXIT_MAX; 232 case _SC_IOV_MAX: return SYSTEM_IOV_MAX; 233 case _SC_PAGESIZE: return PAGE_SIZE; 234 case _SC_PAGE_SIZE: return PAGE_SIZE; 235 #ifdef _XOPEN_UNIX 236 case _SC_XOPEN_UNIX: return _XOPEN_UNIX; 237 #endif 238 239 // XXX: TODO: XBS5 nonsense 240 241 #ifdef AIO_LISTIO_MAX 242 case _SC_AIO_LISTIO_MAX: return AIO_LISTIO_MAX; 243 #endif 244 #ifdef AIO_MAX 245 case _SC_AIO_MAX: return AIO_MAX; 246 #endif 247 #ifdef AIO_PRIO_DELTA_MAX 248 case _SC_AIO_PRIO_DELTA_MAX: return AIO_PRIO_DELTA_MAX; 249 #endif 250 case _SC_DELAYTIMER_MAX: return SYSTEM_DELAYTIMER_MAX; 251 case _SC_MQ_OPEN_MAX: return SYSTEM_MQ_OPEN_MAX; 252 case _SC_MQ_PRIO_MAX: return SYSTEM_MQ_PRIO_MAX; 253 case _SC_RTSIG_MAX: return RTSIG_MAX; 254 case _SC_SEM_NSEMS_MAX: return SYSTEM_SEM_NSEMS_MAX; 255 case _SC_SEM_VALUE_MAX: return SYSTEM_SEM_VALUE_MAX; 256 case _SC_SIGQUEUE_MAX: return SYSTEM_SIGQUEUE_MAX; 257 case _SC_TIMER_MAX: return SYSTEM_TIMER_MAX; 258 #ifdef _POSIX_ASYNCHRONOUS_IO 259 case _SC_ASYNCHRONOUS_IO: return _POSIX_ASYNCHRONOUS_IO; 260 #endif 261 #ifdef _POSIX_FSYNC 262 case _SC_FSYNC: return _POSIX_FSYNC; 263 #endif 264 #ifdef _POSIX_MAPPED_FILES 265 case _SC_MAPPED_FILES: return _POSIX_MAPPED_FILES; 266 #endif 267 #ifdef _POSIX_MEMLOCK 268 case _SC_MEMLOCK: return _POSIX_MEMLOCK; 269 #endif 270 #ifdef _POSIX_MEMLOCK_RANGE 271 case _SC_MEMLOCK_RANGE: return _POSIX_MEMLOCK_RANGE 272 #endif 273 #ifdef _POSIX_MEMORY_PROTECTION 274 case _SC_MEMORY_PROTECTION: return _POSIX_MEMORY_PROTECTION; 275 #endif 276 #ifdef _POSIX_MESSAGE_PASSING 277 case _SC_MESSAGE_PASSING: return _POSIX_MESSAGE_PASSING; 278 #endif 279 #ifdef _POSIX_PRIORITIZED_IO 280 case _SC_PRIORITIZED_IO: return _POSIX_PRIORITIZED_IO; 281 #endif 282 #ifdef _POSIX_PRIORITY_SCHEDULING 283 case _SC_PRIORITY_SCHEDULING: return _POSIX_PRIORITY_SCHEDULING; 284 #endif 285 #ifdef _POSIX_REALTIME_SIGNALS 286 case _SC_REALTIME_SIGNALS: return _POSIX_REALTIME_SIGNALS; 287 #endif 288 #ifdef _POSIX_SEMAPHORES 289 case _SC_SEMAPHORES: return _POSIX_SEMAPHORES; 290 #endif 291 #ifdef _POSIX_SHARED_MEMORY_OBJECTS 292 case _SC_SHARED_MEMORY_OBJECTS: return _POSIX_SHARED_MEMORY_OBJECTS; 293 #endif 294 #ifdef _POSIX_SYNCHRONIZED_IO 295 case _SC_SYNCHRONIZED_IO: return _POSIX_SYNCHRONIZED_IO; 296 #endif 297 #ifdef _POSIX_TIMERS 298 case _SC_TIMERS: return _POSIX_TIMERS; 299 #endif 300 301 case _SC_GETGR_R_SIZE_MAX: return 1024; 302 case _SC_GETPW_R_SIZE_MAX: return 1024; 303 304 case _SC_LOGIN_NAME_MAX: return SYSTEM_LOGIN_NAME_MAX; 305 306 case _SC_THREAD_DESTRUCTOR_ITERATIONS: 307 return _POSIX_THREAD_DESTRUCTOR_ITERATIONS; 308 309 case _SC_THREAD_KEYS_MAX: 310 return (BIONIC_TLS_SLOTS - TLS_SLOT_FIRST_USER_SLOT - GLOBAL_INIT_THREAD_LOCAL_BUFFER_COUNT); 311 312 case _SC_THREAD_STACK_MIN: return PTHREAD_STACK_MIN; 313 case _SC_THREAD_THREADS_MAX: return SYSTEM_THREAD_THREADS_MAX; 314 case _SC_TTY_NAME_MAX: return SYSTEM_TTY_NAME_MAX; 315 #ifdef _POSIX_THREADS 316 case _SC_THREADS: return _POSIX_THREADS; 317 #endif 318 #ifdef _POSIX_THREAD_ATTR_STACKADDR 319 case _SC_THREAD_ATTR_STACKADDR: return _POSIX_THREAD_ATTR_STACKADDR; 320 #endif 321 #ifdef _POSIX_THREAD_ATTR_STACKSIZE 322 case _SC_THREAD_ATTR_STACKSIZE: return _POSIX_THREAD_ATTR_STACKSIZE; 323 #endif 324 #ifdef _POSIX_THREAD_PRIORITY_SCHEDULING 325 case _SC_THREAD_PRIORITY_SCHEDULING: return _POSIX_THREAD_PRIORITY_SCHEDULING; 326 #endif 327 #ifdef _POSIX_THREAD_PRIO_INHERIT 328 case _SC_THREAD_PRIO_INHERIT: return _POSIX_THREAD_PRIO_INHERIT; 329 #endif 330 #ifdef _POSIX_THREAD_PRIO_PROTECT 331 case _SC_THREAD_PRIO_PROTECT: return _POSIX_THREAD_PRIO_PROTECT; 332 #endif 333 #ifdef _POSIX_THREAD_SAFE_FUNCTIONS 334 case _SC_THREAD_SAFE_FUNCTIONS: return _POSIX_THREAD_SAFE_FUNCTIONS 335 #endif 336 337 case _SC_MONOTONIC_CLOCK: return __sysconf_monotonic_clock(); 338 case _SC_NPROCESSORS_CONF: return __sysconf_nprocessors_conf(); 339 case _SC_NPROCESSORS_ONLN: return __sysconf_nprocessors_onln(); 340 case _SC_PHYS_PAGES: return __sysconf_phys_pages(); 341 case _SC_AVPHYS_PAGES: return __sysconf_avphys_pages(); 342 343 default: 344 /* Posix says EINVAL is the only error that shall be returned, 345 * but GLibc uses ENOSYS */ 346 errno = ENOSYS; 347 return -1; 348 } 349 } 350
