| /* |
| * Copyright (C) 2015 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| #include "environment.h" |
| |
| #include <stdlib.h> |
| #include <vector> |
| |
| #include <base/logging.h> |
| |
| #include "utils.h" |
| |
| std::vector<int> GetOnlineCpus() { |
| std::vector<int> result; |
| FILE* fp = fopen("/sys/devices/system/cpu/online", "re"); |
| if (fp == nullptr) { |
| PLOG(ERROR) << "can't open online cpu information"; |
| return result; |
| } |
| |
| LineReader reader(fp); |
| char* line; |
| if ((line = reader.ReadLine()) != nullptr) { |
| result = GetOnlineCpusFromString(line); |
| } |
| CHECK(!result.empty()) << "can't get online cpu information"; |
| return result; |
| } |
| |
| std::vector<int> GetOnlineCpusFromString(const std::string& s) { |
| std::vector<int> result; |
| bool have_dash = false; |
| const char* p = s.c_str(); |
| char* endp; |
| long cpu; |
| // Parse line like: 0,1-3, 5, 7-8 |
| while ((cpu = strtol(p, &endp, 10)) != 0 || endp != p) { |
| if (have_dash && result.size() > 0) { |
| for (int t = result.back() + 1; t < cpu; ++t) { |
| result.push_back(t); |
| } |
| } |
| have_dash = false; |
| result.push_back(cpu); |
| p = endp; |
| while (!isdigit(*p) && *p != '\0') { |
| if (*p == '-') { |
| have_dash = true; |
| } |
| ++p; |
| } |
| } |
| return result; |
| } |