1 /* 2 * Copyright (C) 2019 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #pragma once 18 19 #include <sys/types.h> 20 21 #include <string> 22 23 #include <android/cgrouprc.h> 24 25 // Convenient wrapper of an ACgroupController pointer. 26 class CgroupController { 27 public: 28 // Does not own controller CgroupController(const ACgroupController * controller)29 explicit CgroupController(const ACgroupController* controller) 30 : controller_(controller) {} 31 32 uint32_t version() const; 33 const char* name() const; 34 const char* path() const; 35 36 bool HasValue() const; 37 bool IsUsable(); 38 39 std::string GetTasksFilePath(const std::string& path) const; 40 std::string GetProcsFilePath(const std::string& path, uid_t uid, pid_t pid) const; 41 bool GetTaskGroup(pid_t tid, std::string* group) const; 42 43 private: 44 enum ControllerState { 45 UNKNOWN = 0, 46 USABLE = 1, 47 MISSING = 2, 48 }; 49 50 const ACgroupController* controller_ = nullptr; 51 ControllerState state_ = ControllerState::UNKNOWN; 52 }; 53 54 class CgroupMap { 55 public: 56 // Selinux policy ensures only init process can successfully use this function 57 static bool SetupCgroups(); 58 59 static CgroupMap& GetInstance(); 60 CgroupController FindController(const std::string& name) const; 61 CgroupController FindControllerByPath(const std::string& path) const; 62 int ActivateControllers(const std::string& path) const; 63 64 private: 65 bool loaded_ = false; 66 CgroupMap(); 67 bool LoadRcFile(); 68 void Print() const; 69 }; 70