diff --git a/libc/Android.mk b/libc/Android.mk index e58d4fb20..edf834b70 100644 --- a/libc/Android.mk +++ b/libc/Android.mk @@ -358,7 +358,7 @@ libc_upstream_netbsd_src_files := \ # libc_static_common_src_files := \ bionic/__errno.c \ - bionic/sysconf.c \ + bionic/sysconf.cpp \ # Architecture specific source files go here # ========================================================= diff --git a/libc/bionic/sysconf.cpp b/libc/bionic/sysconf.cpp new file mode 100644 index 000000000..6555a66fa --- /dev/null +++ b/libc/bionic/sysconf.cpp @@ -0,0 +1,346 @@ +/* + * 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 +#include +#include +#include +#include +#include +#include +#include // For FOPEN_MAX. +#include +#include +#include +#include + +/* 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 /* 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. + DIR* d = opendir("/sys/devices/system/cpu"); + if (!d) { + return 1; + } + + int result = 0; + struct dirent* e; + while ((e = readdir(d)) != NULL) { + if (e->d_type == DT_DIR && __matches_cpuN(e->d_name)) { + ++result; + } + } + closedir(d); + 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_ + +#include + +TEST(unistd, sysconf_SC_MONOTONIC_CLOCK) { + ASSERT_GT(sysconf(_SC_MONOTONIC_CLOCK), 0); +}