/* * Copyright (C) 2014 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 "private/ScopedReaddir.h" 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); } int get_nprocs_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; } int get_nprocs() { FILE* fp = fopen("/proc/stat", "re"); 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_page_count(const char* pattern) { FILE* fp = fopen("/proc/meminfo", "re"); if (fp == NULL) { return -1; } int page_count = -1; char buf[256]; while (fgets(buf, sizeof(buf), fp) != NULL) { long total; if (sscanf(buf, pattern, &total) == 1) { page_count = static_cast(total / (PAGE_SIZE / 1024)); break; } } fclose(fp); return page_count; } long get_phys_pages() { return __get_meminfo_page_count("MemTotal: %ld kB"); } long get_avphys_pages() { return __get_meminfo_page_count("MemFree: %ld kB"); }