aosp12/system/gsid/include/libgsi/libgsi.h

123 lines
3.9 KiB
C++

//
// Copyright (C) 2019 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.
//
#pragma once
#include <string>
#include <android-base/file.h>
#include <android-base/strings.h>
namespace android {
namespace gsi {
static constexpr char kGsiServiceName[] = "gsiservice";
#define DSU_METADATA_PREFIX "/metadata/gsi/dsu/"
// These files need to be globally readable so that fs_mgr_fstab, which is
// statically linked into processes, can return consistent result for non-root
// processes:
// * kDsuActiveFile
// * kGsiBootedIndicatorFile
// * kGsiLpNamesFile
// * DsuMetadataKeyDirFile(slot)
static constexpr char kGsiBootedIndicatorFile[] = DSU_METADATA_PREFIX "booted";
static constexpr char kGsiLpNamesFile[] = DSU_METADATA_PREFIX "lp_names";
static constexpr char kDsuActiveFile[] = DSU_METADATA_PREFIX "active";
static constexpr char kDsuAvbKeyDir[] = DSU_METADATA_PREFIX "avb/";
static constexpr char kDsuMetadataKeyDirPrefix[] = "/metadata/vold/metadata_encryption/dsu/";
static constexpr char kDsuSDPrefix[] = "/mnt/media_rw/";
static inline std::string DsuLpMetadataFile(const std::string& dsu_slot) {
return DSU_METADATA_PREFIX + dsu_slot + "/lp_metadata";
}
static inline std::string DsuInstallDirFile(const std::string& dsu_slot) {
return DSU_METADATA_PREFIX + dsu_slot + "/install_dir";
}
static inline std::string DsuMetadataKeyDirFile(const std::string& dsu_slot) {
return DSU_METADATA_PREFIX + dsu_slot + "/metadata_encryption_dir";
}
static inline std::string DefaultDsuMetadataKeyDir(const std::string& dsu_slot) {
return kDsuMetadataKeyDirPrefix + dsu_slot;
}
static inline std::string GetDsuMetadataKeyDir(const std::string& dsu_slot) {
auto key_dir_file = DsuMetadataKeyDirFile(dsu_slot);
std::string key_dir;
if (android::base::ReadFileToString(key_dir_file, &key_dir) &&
android::base::StartsWith(key_dir, kDsuMetadataKeyDirPrefix)) {
return key_dir;
}
return DefaultDsuMetadataKeyDir(dsu_slot);
}
// install_dir "/data/gsi/dsu/dsu" has a slot name "dsu"
// install_dir "/data/gsi/dsu/dsu2" has a slot name "dsu2"
std::string GetDsuSlot(const std::string& install_dir);
static constexpr char kGsiBootedProp[] = "ro.gsid.image_running";
static constexpr char kGsiInstalledProp[] = "gsid.image_installed";
static constexpr char kDsuPostfix[] = "_gsi";
inline constexpr char kDsuScratch[] = "scratch_gsi";
inline constexpr char kDsuUserdata[] = "userdata_gsi";
static constexpr int kMaxBootAttempts = 1;
// Get the currently active dsu slot
// Return true on success
static inline bool GetActiveDsu(std::string* active_dsu) {
return android::base::ReadFileToString(kDsuActiveFile, active_dsu);
}
// Returns true if the currently running system image is a live GSI.
bool IsGsiRunning();
// Return true if a GSI is installed (but not necessarily running).
bool IsGsiInstalled();
// Set the GSI as no longer bootable. This effectively removes the GSI. If no
// GSI was bootable, false is returned.
bool UninstallGsi();
// Set the GSI as no longer bootable, without removing its installed files.
bool DisableGsi();
// Returns true if init should attempt to boot into a live GSI image, false
// otherwise. If false, an error message is set.
//
// This is only called by first-stage init.
bool CanBootIntoGsi(std::string* error);
// Called by first-stage init to indicate that we're about to boot into a
// GSI.
bool MarkSystemAsGsi();
} // namespace gsi
} // namespace android