1 // 2 // Copyright (C) 2015 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 #ifndef UPDATE_ENGINE_BOOT_CONTROL_CHROMEOS_H_ 18 #define UPDATE_ENGINE_BOOT_CONTROL_CHROMEOS_H_ 19 20 #include <string> 21 22 #include <base/callback.h> 23 #include <gtest/gtest_prod.h> // for FRIEND_TEST 24 25 #include "update_engine/common/boot_control_interface.h" 26 27 namespace chromeos_update_engine { 28 29 // The Chrome OS implementation of the BootControlInterface. This interface 30 // assumes the partition names and numbers used in Chrome OS devices. 31 class BootControlChromeOS : public BootControlInterface { 32 public: 33 BootControlChromeOS() = default; 34 ~BootControlChromeOS() = default; 35 36 // Initialize the BootControl instance loading the constant values. Returns 37 // whether the operation succeeded. In case of failure, normally meaning 38 // some critical failure such as we couldn't determine the slot that we 39 // booted from, the implementation will pretend that there's only one slot and 40 // therefore A/B updates are disabled. 41 bool Init(); 42 43 // BootControlInterface overrides. 44 unsigned int GetNumSlots() const override; 45 BootControlInterface::Slot GetCurrentSlot() const override; 46 bool GetPartitionDevice(const std::string& partition_name, 47 BootControlInterface::Slot slot, 48 std::string* device) const override; 49 bool IsSlotBootable(BootControlInterface::Slot slot) const override; 50 bool MarkSlotUnbootable(BootControlInterface::Slot slot) override; 51 bool SetActiveBootSlot(BootControlInterface::Slot slot) override; 52 bool MarkBootSuccessfulAsync(base::Callback<void(bool)> callback) override; 53 54 private: 55 friend class BootControlChromeOSTest; 56 FRIEND_TEST(BootControlChromeOSTest, SysfsBlockDeviceTest); 57 FRIEND_TEST(BootControlChromeOSTest, GetPartitionNumberTest); 58 59 // Returns the sysfs block device for a root block device. For example, 60 // SysfsBlockDevice("/dev/sda") returns "/sys/block/sda". Returns an empty 61 // string if the input device is not of the "/dev/xyz" form. 62 static std::string SysfsBlockDevice(const std::string& device); 63 64 // Returns true if the root |device| (e.g., "/dev/sdb") is known to be 65 // removable, false otherwise. 66 static bool IsRemovableDevice(const std::string& device); 67 68 // Return the hard-coded partition number used in Chrome OS for the passed 69 // |partition_name| and |slot|. In case of invalid data, returns -1. 70 int GetPartitionNumber(const std::string partition_name, 71 BootControlInterface::Slot slot) const; 72 73 // Cached values for GetNumSlots() and GetCurrentSlot(). 74 BootControlInterface::Slot num_slots_{1}; 75 BootControlInterface::Slot current_slot_{BootControlInterface::kInvalidSlot}; 76 77 // The block device of the disk we booted from, without the partition number. 78 std::string boot_disk_name_; 79 80 DISALLOW_COPY_AND_ASSIGN(BootControlChromeOS); 81 }; 82 83 } // namespace chromeos_update_engine 84 85 #endif // UPDATE_ENGINE_BOOT_CONTROL_CHROMEOS_H_ 86
