artd/artd.cc

/*
 * Copyright (C) 2021 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 "artd.h"

#include <fcntl.h>
#include <stdlib.h>
#include <sys/mount.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>

#include <climits>
#include <csignal>
#include <cstdint>
#include <cstring>
#include <filesystem>
#include <functional>
#include <map>
#include <memory>
#include <mutex>
#include <optional>
#include <ostream>
#include <string>
#include <string_view>
#include <system_error>
#include <type_traits>
#include <unordered_set>
#include <utility>
#include <vector>

#include "aidl/com/android/server/art/BnArtd.h"
#include "aidl/com/android/server/art/DexoptTrigger.h"
#include "aidl/com/android/server/art/IArtdCancellationSignal.h"
#include "android-base/errors.h"
#include "android-base/file.h"
#include "android-base/logging.h"
#include "android-base/result.h"
#include "android-base/scopeguard.h"
#include "android-base/strings.h"
#include "android/binder_auto_utils.h"
#include "android/binder_interface_utils.h"
#include "android/binder_manager.h"
#include "android/binder_process.h"
#include "base/compiler_filter.h"
#include "base/file_utils.h"
#include "base/globals.h"
#include "base/logging.h"
#include "base/macros.h"
#include "base/os.h"
#include "cmdline_types.h"
#include "exec_utils.h"
#include "file_utils.h"
#include "fstab/fstab.h"
#include "oat_file_assistant.h"
#include "oat_file_assistant_context.h"
#include "path_utils.h"
#include "profman/profman_result.h"
#include "selinux/android.h"
#include "tools/cmdline_builder.h"
#include "tools/tools.h"

namespace art {
namespace artd {

namespace {

using ::aidl::com::android::server::art::ArtdDexoptResult;
using ::aidl::com::android::server::art::ArtifactsPath;
using ::aidl::com::android::server::art::DexMetadataPath;
using ::aidl::com::android::server::art::DexoptOptions;
using ::aidl::com::android::server::art::DexoptTrigger;
using ::aidl::com::android::server::art::FileVisibility;
using ::aidl::com::android::server::art::FsPermission;
using ::aidl::com::android::server::art::GetDexoptNeededResult;
using ::aidl::com::android::server::art::GetDexoptStatusResult;
using ::aidl::com::android::server::art::IArtdCancellationSignal;
using ::aidl::com::android::server::art::MergeProfileOptions;
using ::aidl::com::android::server::art::OutputArtifacts;
using ::aidl::com::android::server::art::OutputProfile;
using ::aidl::com::android::server::art::PriorityClass;
using ::aidl::com::android::server::art::ProfilePath;
using ::aidl::com::android::server::art::VdexPath;
using ::android::base::Dirname;
using ::android::base::Error;
using ::android::base::Join;
using ::android::base::make_scope_guard;
using ::android::base::ReadFileToString;
using ::android::base::Result;
using ::android::base::Split;
using ::android::base::StringReplace;
using ::android::base::WriteStringToFd;
using ::android::fs_mgr::FstabEntry;
using ::art::tools::CmdlineBuilder;
using ::ndk::ScopedAStatus;

using ArtifactsLocation = GetDexoptNeededResult::ArtifactsLocation;
using TmpProfilePath = ProfilePath::TmpProfilePath;

constexpr const char* kServiceName = "artd";
constexpr const char* kArtdCancellationSignalType = "ArtdCancellationSignal";

// Timeout for short operations, such as merging profiles.
constexpr int kShortTimeoutSec = 60;  // 1 minute.

// Timeout for long operations, such as compilation. We set it to be smaller than the Package
// Manager watchdog (PackageManagerService.WATCHDOG_TIMEOUT, 10 minutes), so that if the operation
// is called from the Package Manager's thread handler, it will be aborted before that watchdog
// would take down the system server.
constexpr int kLongTimeoutSec = 570;  // 9.5 minutes.

std::optional<int64_t> GetSize(std::string_view path) {
  std::error_code ec;
  int64_t size = std::filesystem::file_size(path, ec);
  if (ec) {
    // It is okay if the file does not exist. We don't have to log it.
    if (ec.value() != ENOENT) {
      LOG(ERROR) << ART_FORMAT("Failed to get the file size of '{}': {}", path, ec.message());
    }
    return std::nullopt;
  }
  return size;
}

// Deletes a file. Returns the size of the deleted file, or 0 if the deleted file is empty or an
// error occurs.
int64_t GetSizeAndDeleteFile(const std::string& path) {
  std::optional<int64_t> size = GetSize(path);
  if (!size.has_value()) {
    return 0;
  }

  std::error_code ec;
  if (!std::filesystem::remove(path, ec)) {
    LOG(ERROR) << ART_FORMAT("Failed to remove '{}': {}", path, ec.message());
    return 0;
  }

  return size.value();
}

std::string EscapeErrorMessage(const std::string& message) {
  return StringReplace(message, std::string("\0", /*n=*/1), "\\0", /*all=*/true);
}

// Indicates an error that should never happen (e.g., illegal arguments passed by service-art
// internally). System server should crash if this kind of error happens.
ScopedAStatus Fatal(const std::string& message) {
  return ScopedAStatus::fromExceptionCodeWithMessage(EX_ILLEGAL_STATE,
                                                     EscapeErrorMessage(message).c_str());
}

// Indicates an error that service-art should handle (e.g., I/O errors, sub-process crashes).
// The scope of the error depends on the function that throws it, so service-art should catch the
// error at every call site and take different actions.
// Ideally, this should be a checked exception or an additional return value that forces service-art
// to handle it, but `ServiceSpecificException` (a separate runtime exception type) is the best
// approximate we have given the limitation of Java and Binder.
ScopedAStatus NonFatal(const std::string& message) {
  constexpr int32_t kArtdNonFatalErrorCode = 1;
  return ScopedAStatus::fromServiceSpecificErrorWithMessage(kArtdNonFatalErrorCode,
                                                            EscapeErrorMessage(message).c_str());
}

Result<CompilerFilter::Filter> ParseCompilerFilter(const std::string& compiler_filter_str) {
  CompilerFilter::Filter compiler_filter;
  if (!CompilerFilter::ParseCompilerFilter(compiler_filter_str.c_str(), &compiler_filter)) {
    return Errorf("Failed to parse compiler filter '{}'", compiler_filter_str);
  }
  return compiler_filter;
}

OatFileAssistant::DexOptTrigger DexOptTriggerFromAidl(int32_t aidl_value) {
  OatFileAssistant::DexOptTrigger trigger{};
  if ((aidl_value & static_cast<int32_t>(DexoptTrigger::COMPILER_FILTER_IS_BETTER)) != 0) {
    trigger.targetFilterIsBetter = true;
  }
  if ((aidl_value & static_cast<int32_t>(DexoptTrigger::COMPILER_FILTER_IS_SAME)) != 0) {
    trigger.targetFilterIsSame = true;
  }
  if ((aidl_value & static_cast<int32_t>(DexoptTrigger::COMPILER_FILTER_IS_WORSE)) != 0) {
    trigger.targetFilterIsWorse = true;
  }
  if ((aidl_value & static_cast<int32_t>(DexoptTrigger::PRIMARY_BOOT_IMAGE_BECOMES_USABLE)) != 0) {
    trigger.primaryBootImageBecomesUsable = true;
  }
  if ((aidl_value & static_cast<int32_t>(DexoptTrigger::NEED_EXTRACTION)) != 0) {
    trigger.needExtraction = true;
  }
  return trigger;
}

ArtifactsLocation ArtifactsLocationToAidl(OatFileAssistant::Location location) {
  switch (location) {
    case OatFileAssistant::Location::kLocationNoneOrError:
      return ArtifactsLocation::NONE_OR_ERROR;
    case OatFileAssistant::Location::kLocationOat:
      return ArtifactsLocation::DALVIK_CACHE;
    case OatFileAssistant::Location::kLocationOdex:
      return ArtifactsLocation::NEXT_TO_DEX;
    case OatFileAssistant::Location::kLocationDm:
      return ArtifactsLocation::DM;
      // No default. All cases should be explicitly handled, or the compilation will fail.
  }
  // This should never happen. Just in case we get a non-enumerator value.
  LOG(FATAL) << "Unexpected Location " << location;
}

Result<void> PrepareArtifactsDir(const std::string& path, const FsPermission& fs_permission) {
  std::error_code ec;
  bool created = std::filesystem::create_directory(path, ec);
  if (ec) {
    return Errorf("Failed to create directory '{}': {}", path, ec.message());
  }

  auto cleanup = make_scope_guard([&] {
    if (created) {
      std::filesystem::remove(path, ec);
    }
  });

  if (chmod(path.c_str(), DirFsPermissionToMode(fs_permission)) != 0) {
    return ErrnoErrorf("Failed to chmod directory '{}'", path);
  }
  OR_RETURN(Chown(path, fs_permission));

  cleanup.Disable();
  return {};
}

Result<void> PrepareArtifactsDirs(const OutputArtifacts& output_artifacts,
                                  /*out*/ std::string* oat_dir_path) {
  if (output_artifacts.artifactsPath.isInDalvikCache) {
    return {};
  }

  std::filesystem::path oat_path(OR_RETURN(BuildOatPath(output_artifacts.artifactsPath)));
  std::filesystem::path isa_dir = oat_path.parent_path();
  std::filesystem::path oat_dir = isa_dir.parent_path();
  DCHECK_EQ(oat_dir.filename(), "oat");

  OR_RETURN(PrepareArtifactsDir(oat_dir, output_artifacts.permissionSettings.dirFsPermission));
  OR_RETURN(PrepareArtifactsDir(isa_dir, output_artifacts.permissionSettings.dirFsPermission));
  *oat_dir_path = oat_dir;
  return {};
}

Result<void> Restorecon(
    const std::string& path,
    const std::optional<OutputArtifacts::PermissionSettings::SeContext>& se_context) {
  if (!kIsTargetAndroid) {
    return {};
  }

  int res = 0;
  if (se_context.has_value()) {
    res = selinux_android_restorecon_pkgdir(path.c_str(),
                                            se_context->seInfo.c_str(),
                                            se_context->uid,
                                            SELINUX_ANDROID_RESTORECON_RECURSE);
  } else {
    res = selinux_android_restorecon(path.c_str(), SELINUX_ANDROID_RESTORECON_RECURSE);
  }
  if (res != 0) {
    return ErrnoErrorf("Failed to restorecon directory '{}'", path);
  }
  return {};
}

Result<FileVisibility> GetFileVisibility(const std::string& file) {
  std::error_code ec;
  std::filesystem::file_status status = std::filesystem::status(file, ec);
  if (!std::filesystem::status_known(status)) {
    return Errorf("Failed to get status of '{}': {}", file, ec.message());
  }
  if (!std::filesystem::exists(status)) {
    return FileVisibility::NOT_FOUND;
  }

  return (status.permissions() & std::filesystem::perms::others_read) !=
                 std::filesystem::perms::none ?
             FileVisibility::OTHER_READABLE :
             FileVisibility::NOT_OTHER_READABLE;
}

Result<ArtdCancellationSignal*> ToArtdCancellationSignal(IArtdCancellationSignal* input) {
  if (input == nullptr) {
    return Error() << "Cancellation signal must not be nullptr";
  }
  // We cannot use `dynamic_cast` because ART code is compiled with `-fno-rtti`, so we have to check
  // the magic number.
  int64_t type;
  if (!input->getType(&type).isOk() ||
      type != reinterpret_cast<intptr_t>(kArtdCancellationSignalType)) {
    // The cancellation signal must be created by `Artd::createCancellationSignal`.
    return Error() << "Invalid cancellation signal type";
  }
  return static_cast<ArtdCancellationSignal*>(input);
}

Result<void> CopyFile(const std::string& src_path, const NewFile& dst_file) {
  std::string content;
  if (!ReadFileToString(src_path, &content)) {
    return Errorf("Failed to read file '{}': {}", src_path, strerror(errno));
  }
  if (!WriteStringToFd(content, dst_file.Fd())) {
    return Errorf("Failed to write file '{}': {}", dst_file.TempPath(), strerror(errno));
  }
  if (fsync(dst_file.Fd()) != 0) {
    return Errorf("Failed to flush file '{}': {}", dst_file.TempPath(), strerror(errno));
  }
  if (lseek(dst_file.Fd(), /*offset=*/0, SEEK_SET) != 0) {
    return Errorf(
        "Failed to reset the offset for file '{}': {}", dst_file.TempPath(), strerror(errno));
  }
  return {};
}

Result<void> SetLogVerbosity() {
  std::string options = android::base::GetProperty("dalvik.vm.artd-verbose", /*default_value=*/"");
  if (options.empty()) {
    return {};
  }

  CmdlineType<LogVerbosity> parser;
  CmdlineParseResult<LogVerbosity> result = parser.Parse(options);
  if (!result.IsSuccess()) {
    return Error() << result.GetMessage();
  }

  gLogVerbosity = result.ReleaseValue();
  return {};
}

class FdLogger {
 public:
  void Add(const NewFile& file) { fd_mapping_.emplace_back(file.Fd(), file.TempPath()); }
  void Add(const File& file) { fd_mapping_.emplace_back(file.Fd(), file.GetPath()); }

  std::string GetFds() {
    std::vector<int> fds;
    fds.reserve(fd_mapping_.size());
    for (const auto& [fd, path] : fd_mapping_) {
      fds.push_back(fd);
    }
    return Join(fds, ':');
  }

 private:
  std::vector<std::pair<int, std::string>> fd_mapping_;

  friend std::ostream& operator<<(std::ostream& os, const FdLogger& fd_logger);
};

std::ostream& operator<<(std::ostream& os, const FdLogger& fd_logger) {
  for (const auto& [fd, path] : fd_logger.fd_mapping_) {
    os << fd << ":" << path << ' ';
  }
  return os;
}

}  // namespace

#define OR_RETURN_ERROR(func, expr)         \
  ({                                        \
    decltype(expr)&& tmp = (expr);          \
    if (!tmp.ok()) {                        \
      return (func)(tmp.error().message()); \
    }                                       \
    std::move(tmp).value();                 \
  })

#define OR_RETURN_FATAL(expr)     OR_RETURN_ERROR(Fatal, expr)
#define OR_RETURN_NON_FATAL(expr) OR_RETURN_ERROR(NonFatal, expr)

ScopedAStatus Artd::isAlive(bool* _aidl_return) {
  *_aidl_return = true;
  return ScopedAStatus::ok();
}

ScopedAStatus Artd::deleteArtifacts(const ArtifactsPath& in_artifactsPath, int64_t* _aidl_return) {
  std::string oat_path = OR_RETURN_FATAL(BuildOatPath(in_artifactsPath));

  *_aidl_return = 0;
  *_aidl_return += GetSizeAndDeleteFile(oat_path);
  *_aidl_return += GetSizeAndDeleteFile(OatPathToVdexPath(oat_path));
  *_aidl_return += GetSizeAndDeleteFile(OatPathToArtPath(oat_path));

  return ScopedAStatus::ok();
}

ScopedAStatus Artd::getDexoptStatus(const std::string& in_dexFile,
                                    const std::string& in_instructionSet,
                                    const std::optional<std::string>& in_classLoaderContext,
                                    GetDexoptStatusResult* _aidl_return) {
  Result<OatFileAssistantContext*> ofa_context = GetOatFileAssistantContext();
  if (!ofa_context.ok()) {
    return NonFatal("Failed to get runtime options: " + ofa_context.error().message());
  }

  std::unique_ptr<ClassLoaderContext> context;
  std::string error_msg;
  auto oat_file_assistant = OatFileAssistant::Create(in_dexFile,
                                                     in_instructionSet,
                                                     in_classLoaderContext,
                                                     /*load_executable=*/false,
                                                     /*only_load_trusted_executable=*/true,
                                                     ofa_context.value(),
                                                     &context,
                                                     &error_msg);
  if (oat_file_assistant == nullptr) {
    return NonFatal("Failed to create OatFileAssistant: " + error_msg);
  }

  std::string ignored_odex_status;
  oat_file_assistant->GetOptimizationStatus(&_aidl_return->locationDebugString,
                                            &_aidl_return->compilerFilter,
                                            &_aidl_return->compilationReason,
                                            &ignored_odex_status);

  // We ignore odex_status because it is not meaningful. It can only be either "up-to-date",
  // "apk-more-recent", or "io-error-no-oat", which means it doesn't give us information in addition
  // to what we can learn from compiler_filter because compiler_filter will be the actual compiler
  // filter, "run-from-apk-fallback", and "run-from-apk" in those three cases respectively.
  DCHECK(ignored_odex_status == "up-to-date" || ignored_odex_status == "apk-more-recent" ||
         ignored_odex_status == "io-error-no-oat");

  return ScopedAStatus::ok();
}

ndk::ScopedAStatus Artd::isProfileUsable(const ProfilePath& in_profile,
                                         const std::string& in_dexFile,
                                         bool* _aidl_return) {
  std::string profile_path = OR_RETURN_FATAL(BuildProfileOrDmPath(in_profile));
  OR_RETURN_FATAL(ValidateDexPath(in_dexFile));

  FdLogger fd_logger;

  CmdlineBuilder art_exec_args;
  art_exec_args.Add(OR_RETURN_FATAL(GetArtExec())).Add("--drop-capabilities");

  CmdlineBuilder args;
  args.Add(OR_RETURN_FATAL(GetProfman()));

  Result<std::unique_ptr<File>> profile = OpenFileForReading(profile_path);
  if (!profile.ok()) {
    if (profile.error().code() == ENOENT) {
      *_aidl_return = false;
      return ScopedAStatus::ok();
    }
    return NonFatal(
        ART_FORMAT("Failed to open profile '{}': {}", profile_path, profile.error().message()));
  }
  args.Add("--reference-profile-file-fd=%d", profile.value()->Fd());
  fd_logger.Add(*profile.value());

  std::unique_ptr<File> dex_file = OR_RETURN_NON_FATAL(OpenFileForReading(in_dexFile));
  args.Add("--apk-fd=%d", dex_file->Fd());
  fd_logger.Add(*dex_file);

  art_exec_args.Add("--keep-fds=%s", fd_logger.GetFds()).Add("--").Concat(std::move(args));

  LOG(INFO) << "Running profman: " << Join(art_exec_args.Get(), /*separator=*/" ")
            << "\nOpened FDs: " << fd_logger;

  Result<int> result = ExecAndReturnCode(art_exec_args.Get(), kShortTimeoutSec);
  if (!result.ok()) {
    return NonFatal("Failed to run profman: " + result.error().message());
  }

  LOG(INFO) << ART_FORMAT("profman returned code {}", result.value());

  if (result.value() != ProfmanResult::kSkipCompilationSmallDelta &&
      result.value() != ProfmanResult::kSkipCompilationEmptyProfiles) {
    return NonFatal(ART_FORMAT("profman returned an unexpected code: {}", result.value()));
  }

  *_aidl_return = result.value() == ProfmanResult::kSkipCompilationSmallDelta;
  return ScopedAStatus::ok();
}

ndk::ScopedAStatus Artd::copyAndRewriteProfile(const ProfilePath& in_src,
                                               OutputProfile* in_dst,
                                               const std::string& in_dexFile,
                                               bool* _aidl_return) {
  std::string src_path = OR_RETURN_FATAL(BuildProfileOrDmPath(in_src));
  std::string dst_path = OR_RETURN_FATAL(BuildFinalProfilePath(in_dst->profilePath));
  OR_RETURN_FATAL(ValidateDexPath(in_dexFile));

  FdLogger fd_logger;

  CmdlineBuilder art_exec_args;
  art_exec_args.Add(OR_RETURN_FATAL(GetArtExec())).Add("--drop-capabilities");

  CmdlineBuilder args;
  args.Add(OR_RETURN_FATAL(GetProfman())).Add("--copy-and-update-profile-key");

  Result<std::unique_ptr<File>> src = OpenFileForReading(src_path);
  if (!src.ok()) {
    if (src.error().code() == ENOENT) {
      *_aidl_return = false;
      return ScopedAStatus::ok();
    }
    return NonFatal(
        ART_FORMAT("Failed to open src profile '{}': {}", src_path, src.error().message()));
  }
  args.Add("--profile-file-fd=%d", src.value()->Fd());
  fd_logger.Add(*src.value());

  std::unique_ptr<File> dex_file = OR_RETURN_NON_FATAL(OpenFileForReading(in_dexFile));
  args.Add("--apk-fd=%d", dex_file->Fd());
  fd_logger.Add(*dex_file);

  std::unique_ptr<NewFile> dst =
      OR_RETURN_NON_FATAL(NewFile::Create(dst_path, in_dst->fsPermission));
  args.Add("--reference-profile-file-fd=%d", dst->Fd());
  fd_logger.Add(*dst);

  art_exec_args.Add("--keep-fds=%s", fd_logger.GetFds()).Add("--").Concat(std::move(args));

  LOG(INFO) << "Running profman: " << Join(art_exec_args.Get(), /*separator=*/" ")
            << "\nOpened FDs: " << fd_logger;

  Result<int> result = ExecAndReturnCode(art_exec_args.Get(), kShortTimeoutSec);
  if (!result.ok()) {
    return NonFatal("Failed to run profman: " + result.error().message());
  }

  LOG(INFO) << ART_FORMAT("profman returned code {}", result.value());

  if (result.value() == ProfmanResult::kCopyAndUpdateNoMatch) {
    *_aidl_return = false;
    return ScopedAStatus::ok();
  }

  if (result.value() != ProfmanResult::kCopyAndUpdateSuccess) {
    return NonFatal(ART_FORMAT("profman returned an unexpected code: {}", result.value()));
  }

  OR_RETURN_NON_FATAL(dst->Keep());
  *_aidl_return = true;
  in_dst->profilePath.id = dst->TempId();
  in_dst->profilePath.tmpPath = dst->TempPath();
  return ScopedAStatus::ok();
}

ndk::ScopedAStatus Artd::commitTmpProfile(const TmpProfilePath& in_profile) {
  std::string tmp_profile_path = OR_RETURN_FATAL(BuildTmpProfilePath(in_profile));
  std::string ref_profile_path = OR_RETURN_FATAL(BuildFinalProfilePath(in_profile));

  std::error_code ec;
  std::filesystem::rename(tmp_profile_path, ref_profile_path, ec);
  if (ec) {
    return NonFatal(ART_FORMAT(
        "Failed to move '{}' to '{}': {}", tmp_profile_path, ref_profile_path, ec.message()));
  }

  return ScopedAStatus::ok();
}

ndk::ScopedAStatus Artd::deleteProfile(const ProfilePath& in_profile) {
  std::string profile_path = OR_RETURN_FATAL(BuildProfileOrDmPath(in_profile));

  std::error_code ec;
  std::filesystem::remove(profile_path, ec);
  if (ec) {
    LOG(ERROR) << ART_FORMAT("Failed to remove '{}': {}", profile_path, ec.message());
  }

  return ScopedAStatus::ok();
}

ndk::ScopedAStatus Artd::getProfileVisibility(const ProfilePath& in_profile,
                                              FileVisibility* _aidl_return) {
  std::string profile_path = OR_RETURN_FATAL(BuildProfileOrDmPath(in_profile));
  *_aidl_return = OR_RETURN_NON_FATAL(GetFileVisibility(profile_path));
  return ScopedAStatus::ok();
}

ndk::ScopedAStatus Artd::getArtifactsVisibility(const ArtifactsPath& in_artifactsPath,
                                                FileVisibility* _aidl_return) {
  std::string oat_path = OR_RETURN_FATAL(BuildOatPath(in_artifactsPath));
  *_aidl_return = OR_RETURN_NON_FATAL(GetFileVisibility(oat_path));
  return ScopedAStatus::ok();
}

ndk::ScopedAStatus Artd::getDexFileVisibility(const std::string& in_dexFile,
                                              FileVisibility* _aidl_return) {
  OR_RETURN_FATAL(ValidateDexPath(in_dexFile));
  *_aidl_return = OR_RETURN_NON_FATAL(GetFileVisibility(in_dexFile));
  return ScopedAStatus::ok();
}

ndk::ScopedAStatus Artd::getDmFileVisibility(const DexMetadataPath& in_dmFile,
                                             FileVisibility* _aidl_return) {
  std::string dm_path = OR_RETURN_FATAL(BuildDexMetadataPath(in_dmFile));
  *_aidl_return = OR_RETURN_NON_FATAL(GetFileVisibility(dm_path));
  return ScopedAStatus::ok();
}

ndk::ScopedAStatus Artd::mergeProfiles(const std::vector<ProfilePath>& in_profiles,
                                       const std::optional<ProfilePath>& in_referenceProfile,
                                       OutputProfile* in_outputProfile,
                                       const std::vector<std::string>& in_dexFiles,
                                       const MergeProfileOptions& in_options,
                                       bool* _aidl_return) {
  std::vector<std::string> profile_paths;
  for (const ProfilePath& profile : in_profiles) {
    std::string profile_path = OR_RETURN_FATAL(BuildProfileOrDmPath(profile));
    if (profile.getTag() == ProfilePath::dexMetadataPath) {
      return Fatal(ART_FORMAT("Does not support DM file, got '{}'", profile_path));
    }
    profile_paths.push_back(std::move(profile_path));
  }
  std::string output_profile_path =
      OR_RETURN_FATAL(BuildFinalProfilePath(in_outputProfile->profilePath));
  for (const std::string& dex_file : in_dexFiles) {
    OR_RETURN_FATAL(ValidateDexPath(dex_file));
  }
  if (in_options.forceMerge + in_options.dumpOnly + in_options.dumpClassesAndMethods > 1) {
    return Fatal("Only one of 'forceMerge', 'dumpOnly', and 'dumpClassesAndMethods' can be set");
  }

  FdLogger fd_logger;

  CmdlineBuilder art_exec_args;
  art_exec_args.Add(OR_RETURN_FATAL(GetArtExec())).Add("--drop-capabilities");

  CmdlineBuilder args;
  args.Add(OR_RETURN_FATAL(GetProfman()));

  std::vector<std::unique_ptr<File>> profile_files;
  for (const std::string& profile_path : profile_paths) {
    Result<std::unique_ptr<File>> profile_file = OpenFileForReading(profile_path);
    if (!profile_file.ok()) {
      if (profile_file.error().code() == ENOENT) {
        // Skip non-existing file.
        continue;
      }
      return NonFatal(ART_FORMAT(
          "Failed to open profile '{}': {}", profile_path, profile_file.error().message()));
    }
    args.Add("--profile-file-fd=%d", profile_file.value()->Fd());
    fd_logger.Add(*profile_file.value());
    profile_files.push_back(std::move(profile_file.value()));
  }

  if (profile_files.empty()) {
    LOG(INFO) << "Merge skipped because there are no existing profiles";
    *_aidl_return = false;
    return ScopedAStatus::ok();
  }

  std::unique_ptr<NewFile> output_profile_file =
      OR_RETURN_NON_FATAL(NewFile::Create(output_profile_path, in_outputProfile->fsPermission));

  if (in_referenceProfile.has_value()) {
    if (in_options.forceMerge || in_options.dumpOnly || in_options.dumpClassesAndMethods) {
      return Fatal(
          "Reference profile must not be set when 'forceMerge', 'dumpOnly', or "
          "'dumpClassesAndMethods' is set");
    }
    std::string reference_profile_path =
        OR_RETURN_FATAL(BuildProfileOrDmPath(*in_referenceProfile));
    if (in_referenceProfile->getTag() == ProfilePath::dexMetadataPath) {
      return Fatal(ART_FORMAT("Does not support DM file, got '{}'", reference_profile_path));
    }
    OR_RETURN_NON_FATAL(CopyFile(reference_profile_path, *output_profile_file));
  }

  if (in_options.dumpOnly || in_options.dumpClassesAndMethods) {
    args.Add("--dump-output-to-fd=%d", output_profile_file->Fd());
  } else {
    // profman is ok with this being an empty file when in_referenceProfile isn't set.
    args.Add("--reference-profile-file-fd=%d", output_profile_file->Fd());
  }
  fd_logger.Add(*output_profile_file);

  std::vector<std::unique_ptr<File>> dex_files;
  for (const std::string& dex_path : in_dexFiles) {
    std::unique_ptr<File> dex_file = OR_RETURN_NON_FATAL(OpenFileForReading(dex_path));
    args.Add("--apk-fd=%d", dex_file->Fd());
    fd_logger.Add(*dex_file);
    dex_files.push_back(std::move(dex_file));
  }

  if (in_options.dumpOnly || in_options.dumpClassesAndMethods) {
    args.Add(in_options.dumpOnly ? "--dump-only" : "--dump-classes-and-methods");
  } else {
    args.AddIfNonEmpty("--min-new-classes-percent-change=%s",
                       props_->GetOrEmpty("dalvik.vm.bgdexopt.new-classes-percent"))
        .AddIfNonEmpty("--min-new-methods-percent-change=%s",
                       props_->GetOrEmpty("dalvik.vm.bgdexopt.new-methods-percent"))
        .AddIf(in_options.forceMerge, "--force-merge")
        .AddIf(in_options.forBootImage, "--boot-image-merge");
  }

  art_exec_args.Add("--keep-fds=%s", fd_logger.GetFds()).Add("--").Concat(std::move(args));

  LOG(INFO) << "Running profman: " << Join(art_exec_args.Get(), /*separator=*/" ")
            << "\nOpened FDs: " << fd_logger;

  Result<int> result = ExecAndReturnCode(art_exec_args.Get(), kShortTimeoutSec);
  if (!result.ok()) {
    return NonFatal("Failed to run profman: " + result.error().message());
  }

  LOG(INFO) << ART_FORMAT("profman returned code {}", result.value());

  if (result.value() == ProfmanResult::kSkipCompilationSmallDelta ||
      result.value() == ProfmanResult::kSkipCompilationEmptyProfiles) {
    *_aidl_return = false;
    return ScopedAStatus::ok();
  }

  ProfmanResult::ProcessingResult expected_result =
      (in_options.forceMerge || in_options.dumpOnly || in_options.dumpClassesAndMethods) ?
          ProfmanResult::kSuccess :
          ProfmanResult::kCompile;
  if (result.value() != expected_result) {
    return NonFatal(ART_FORMAT("profman returned an unexpected code: {}", result.value()));
  }

  OR_RETURN_NON_FATAL(output_profile_file->Keep());
  *_aidl_return = true;
  in_outputProfile->profilePath.id = output_profile_file->TempId();
  in_outputProfile->profilePath.tmpPath = output_profile_file->TempPath();
  return ScopedAStatus::ok();
}

ndk::ScopedAStatus Artd::getDexoptNeeded(const std::string& in_dexFile,
                                         const std::string& in_instructionSet,
                                         const std::optional<std::string>& in_classLoaderContext,
                                         const std::string& in_compilerFilter,
                                         int32_t in_dexoptTrigger,
                                         GetDexoptNeededResult* _aidl_return) {
  Result<OatFileAssistantContext*> ofa_context = GetOatFileAssistantContext();
  if (!ofa_context.ok()) {
    return NonFatal("Failed to get runtime options: " + ofa_context.error().message());
  }

  std::unique_ptr<ClassLoaderContext> context;
  std::string error_msg;
  auto oat_file_assistant = OatFileAssistant::Create(in_dexFile,
                                                     in_instructionSet,
                                                     in_classLoaderContext,
                                                     /*load_executable=*/false,
                                                     /*only_load_trusted_executable=*/true,
                                                     ofa_context.value(),
                                                     &context,
                                                     &error_msg);
  if (oat_file_assistant == nullptr) {
    return NonFatal("Failed to create OatFileAssistant: " + error_msg);
  }

  OatFileAssistant::DexOptStatus status;
  _aidl_return->isDexoptNeeded =
      oat_file_assistant->GetDexOptNeeded(OR_RETURN_FATAL(ParseCompilerFilter(in_compilerFilter)),
                                          DexOptTriggerFromAidl(in_dexoptTrigger),
                                          &status);
  _aidl_return->isVdexUsable = status.IsVdexUsable();
  _aidl_return->artifactsLocation = ArtifactsLocationToAidl(status.GetLocation());

  std::optional<bool> has_dex_files = oat_file_assistant->HasDexFiles(&error_msg);
  if (!has_dex_files.has_value()) {
    return NonFatal("Failed to open dex file: " + error_msg);
  }
  _aidl_return->hasDexCode = *has_dex_files;

  return ScopedAStatus::ok();
}

ndk::ScopedAStatus Artd::dexopt(
    const OutputArtifacts& in_outputArtifacts,
    const std::string& in_dexFile,
    const std::string& in_instructionSet,
    const std::optional<std::string>& in_classLoaderContext,
    const std::string& in_compilerFilter,
    const std::optional<ProfilePath>& in_profile,
    const std::optional<VdexPath>& in_inputVdex,
    const std::optional<DexMetadataPath>& in_dmFile,
    PriorityClass in_priorityClass,
    const DexoptOptions& in_dexoptOptions,
    const std::shared_ptr<IArtdCancellationSignal>& in_cancellationSignal,
    ArtdDexoptResult* _aidl_return) {
  _aidl_return->cancelled = false;

  std::string oat_path = OR_RETURN_FATAL(BuildOatPath(in_outputArtifacts.artifactsPath));
  std::string vdex_path = OatPathToVdexPath(oat_path);
  std::string art_path = OatPathToArtPath(oat_path);
  OR_RETURN_FATAL(ValidateDexPath(in_dexFile));
  std::optional<std::string> profile_path =
      in_profile.has_value() ?
          std::make_optional(OR_RETURN_FATAL(BuildProfileOrDmPath(in_profile.value()))) :
          std::nullopt;
  ArtdCancellationSignal* cancellation_signal =
      OR_RETURN_FATAL(ToArtdCancellationSignal(in_cancellationSignal.get()));

  std::unique_ptr<ClassLoaderContext> context = nullptr;
  if (in_classLoaderContext.has_value()) {
    context = ClassLoaderContext::Create(in_classLoaderContext.value());
    if (context == nullptr) {
      return Fatal(
          ART_FORMAT("Class loader context '{}' is invalid", in_classLoaderContext.value()));
    }
  }

  std::string oat_dir_path;  // For restorecon, can be empty if the artifacts are in dalvik-cache.
  OR_RETURN_NON_FATAL(PrepareArtifactsDirs(in_outputArtifacts, &oat_dir_path));

  // First-round restorecon. artd doesn't have the permission to create files with the
  // `apk_data_file` label, so we need to restorecon the "oat" directory first so that files will
  // inherit `dalvikcache_data_file` rather than `apk_data_file`.
  if (!in_outputArtifacts.artifactsPath.isInDalvikCache) {
    OR_RETURN_NON_FATAL(Restorecon(oat_dir_path, in_outputArtifacts.permissionSettings.seContext));
  }

  FdLogger fd_logger;

  CmdlineBuilder art_exec_args;
  art_exec_args.Add(OR_RETURN_FATAL(GetArtExec())).Add("--drop-capabilities");

  CmdlineBuilder args;
  args.Add(OR_RETURN_FATAL(GetDex2Oat()));

  const FsPermission& fs_permission = in_outputArtifacts.permissionSettings.fileFsPermission;

  std::unique_ptr<File> dex_file = OR_RETURN_NON_FATAL(OpenFileForReading(in_dexFile));
  args.Add("--zip-fd=%d", dex_file->Fd()).Add("--zip-location=%s", in_dexFile);
  fd_logger.Add(*dex_file);
  struct stat dex_st = OR_RETURN_NON_FATAL(Fstat(*dex_file));
  if ((dex_st.st_mode & S_IROTH) == 0) {
    if (fs_permission.isOtherReadable) {
      return NonFatal(ART_FORMAT(
          "Outputs cannot be other-readable because the dex file '{}' is not other-readable",
          dex_file->GetPath()));
    }
    // Negative numbers mean no `chown`. 0 means root.
    // Note: this check is more strict than it needs to be. For example, it doesn't allow the
    // outputs to belong to a group that is a subset of the dex file's group. This is for
    // simplicity, and it's okay as we don't have to handle such complicated cases in practice.
    if ((fs_permission.uid > 0 && static_cast<uid_t>(fs_permission.uid) != dex_st.st_uid) ||
        (fs_permission.gid > 0 && static_cast<gid_t>(fs_permission.gid) != dex_st.st_uid &&
         static_cast<gid_t>(fs_permission.gid) != dex_st.st_gid)) {
      return NonFatal(ART_FORMAT(
          "Outputs' owner doesn't match the dex file '{}' (outputs: {}:{}, dex file: {}:{})",
          dex_file->GetPath(),
          fs_permission.uid,
          fs_permission.gid,
          dex_st.st_uid,
          dex_st.st_gid));
    }
  }

  std::unique_ptr<NewFile> oat_file = OR_RETURN_NON_FATAL(NewFile::Create(oat_path, fs_permission));
  args.Add("--oat-fd=%d", oat_file->Fd()).Add("--oat-location=%s", oat_path);
  fd_logger.Add(*oat_file);

  std::unique_ptr<NewFile> vdex_file =
      OR_RETURN_NON_FATAL(NewFile::Create(vdex_path, fs_permission));
  args.Add("--output-vdex-fd=%d", vdex_file->Fd());
  fd_logger.Add(*vdex_file);

  std::vector<NewFile*> files_to_commit{oat_file.get(), vdex_file.get()};
  std::vector<std::string_view> files_to_delete;

  std::unique_ptr<NewFile> art_file = nullptr;
  if (in_dexoptOptions.generateAppImage) {
    art_file = OR_RETURN_NON_FATAL(NewFile::Create(art_path, fs_permission));
    args.Add("--app-image-fd=%d", art_file->Fd());
    args.AddIfNonEmpty("--image-format=%s", props_->GetOrEmpty("dalvik.vm.appimageformat"));
    fd_logger.Add(*art_file);
    files_to_commit.push_back(art_file.get());
  } else {
    files_to_delete.push_back(art_path);
  }

  std::unique_ptr<NewFile> swap_file = nullptr;
  if (ShouldCreateSwapFileForDexopt()) {
    std::string swap_file_path = ART_FORMAT("{}.swap", oat_path);
    swap_file =
        OR_RETURN_NON_FATAL(NewFile::Create(swap_file_path, FsPermission{.uid = -1, .gid = -1}));
    args.Add("--swap-fd=%d", swap_file->Fd());
    fd_logger.Add(*swap_file);
  }

  std::vector<std::unique_ptr<File>> context_files;
  if (context != nullptr) {
    std::vector<std::string> flattened_context = context->FlattenDexPaths();
    std::string dex_dir = Dirname(in_dexFile);
    std::vector<int> context_fds;
    for (const std::string& context_element : flattened_context) {
      std::string context_path = std::filesystem::path(dex_dir).append(context_element);
      OR_RETURN_FATAL(ValidateDexPath(context_path));
      std::unique_ptr<File> context_file = OR_RETURN_NON_FATAL(OpenFileForReading(context_path));
      context_fds.push_back(context_file->Fd());
      fd_logger.Add(*context_file);
      context_files.push_back(std::move(context_file));
    }
    args.AddIfNonEmpty("--class-loader-context-fds=%s", Join(context_fds, /*separator=*/':'))
        .Add("--class-loader-context=%s", in_classLoaderContext.value())
        .Add("--classpath-dir=%s", dex_dir);
  }

  std::unique_ptr<File> input_vdex_file = nullptr;
  if (in_inputVdex.has_value()) {
    std::string input_vdex_path = OR_RETURN_FATAL(BuildVdexPath(in_inputVdex.value()));
    input_vdex_file = OR_RETURN_NON_FATAL(OpenFileForReading(input_vdex_path));
    args.Add("--input-vdex-fd=%d", input_vdex_file->Fd());
    fd_logger.Add(*input_vdex_file);
  }

  std::unique_ptr<File> dm_file = nullptr;
  if (in_dmFile.has_value()) {
    std::string dm_path = OR_RETURN_FATAL(BuildDexMetadataPath(in_dmFile.value()));
    dm_file = OR_RETURN_NON_FATAL(OpenFileForReading(dm_path));
    args.Add("--dm-fd=%d", dm_file->Fd());
    fd_logger.Add(*dm_file);
  }

  std::unique_ptr<File> profile_file = nullptr;
  if (profile_path.has_value()) {
    profile_file = OR_RETURN_NON_FATAL(OpenFileForReading(profile_path.value()));
    args.Add("--profile-file-fd=%d", profile_file->Fd());
    fd_logger.Add(*profile_file);
    struct stat profile_st = OR_RETURN_NON_FATAL(Fstat(*profile_file));
    if (fs_permission.isOtherReadable && (profile_st.st_mode & S_IROTH) == 0) {
      return NonFatal(ART_FORMAT(
          "Outputs cannot be other-readable because the profile '{}' is not other-readable",
          profile_file->GetPath()));
    }
    // TODO(b/260228411): Check uid and gid.
  }

  // Second-round restorecon. Restorecon recursively after the output files are created, so that the
  // SELinux context is applied to all of them. The SELinux context of a file is mostly inherited
  // from the parent directory upon creation, but the MLS label is not inherited, so we need to
  // restorecon every file so that they have the right MLS label. If the files are in dalvik-cache,
  // there's no need to restorecon because they inherits the SELinux context of the dalvik-cache
  // directory and they don't need to have MLS labels.
  if (!in_outputArtifacts.artifactsPath.isInDalvikCache) {
    OR_RETURN_NON_FATAL(Restorecon(oat_dir_path, in_outputArtifacts.permissionSettings.seContext));
  }

  AddBootImageFlags(args);
  AddCompilerConfigFlags(
      in_instructionSet, in_compilerFilter, in_priorityClass, in_dexoptOptions, args);
  AddPerfConfigFlags(in_priorityClass, art_exec_args, args);

  // For being surfaced in crash reports on crashes.
  args.Add("--comments=%s", in_dexoptOptions.comments);

  art_exec_args.Add("--keep-fds=%s", fd_logger.GetFds()).Add("--").Concat(std::move(args));

  LOG(INFO) << "Running dex2oat: " << Join(art_exec_args.Get(), /*separator=*/" ")
            << "\nOpened FDs: " << fd_logger;

  ExecCallbacks callbacks{
      .on_start =
          [&](pid_t pid) {
            std::lock_guard<std::mutex> lock(cancellation_signal->mu_);
            cancellation_signal->pids_.insert(pid);
            // Handle cancellation signals sent before the process starts.
            if (cancellation_signal->is_cancelled_) {
              int res = kill_(pid, SIGKILL);
              DCHECK_EQ(res, 0);
            }
          },
      .on_end =
          [&](pid_t pid) {
            std::lock_guard<std::mutex> lock(cancellation_signal->mu_);
            // The pid should no longer receive kill signals sent by `cancellation_signal`.
            cancellation_signal->pids_.erase(pid);
          },
  };

  ProcessStat stat;
  Result<int> result = ExecAndReturnCode(art_exec_args.Get(), kLongTimeoutSec, callbacks, &stat);
  _aidl_return->wallTimeMs = stat.wall_time_ms;
  _aidl_return->cpuTimeMs = stat.cpu_time_ms;
  if (!result.ok()) {
    {
      std::lock_guard<std::mutex> lock(cancellation_signal->mu_);
      if (cancellation_signal->is_cancelled_) {
        _aidl_return->cancelled = true;
        return ScopedAStatus::ok();
      }
    }
    return NonFatal("Failed to run dex2oat: " + result.error().message());
  }

  LOG(INFO) << ART_FORMAT("dex2oat returned code {}", result.value());

  if (result.value() != 0) {
    return NonFatal(ART_FORMAT("dex2oat returned an unexpected code: {}", result.value()));
  }

  int64_t size_bytes = 0;
  int64_t size_before_bytes = 0;
  for (const NewFile* file : files_to_commit) {
    size_bytes += GetSize(file->TempPath()).value_or(0);
    size_before_bytes += GetSize(file->FinalPath()).value_or(0);
  }
  for (std::string_view path : files_to_delete) {
    size_before_bytes += GetSize(path).value_or(0);
  }
  OR_RETURN_NON_FATAL(NewFile::CommitAllOrAbandon(files_to_commit, files_to_delete));

  _aidl_return->sizeBytes = size_bytes;
  _aidl_return->sizeBeforeBytes = size_before_bytes;
  return ScopedAStatus::ok();
}

ScopedAStatus ArtdCancellationSignal::cancel() {
  std::lock_guard<std::mutex> lock(mu_);
  is_cancelled_ = true;
  for (pid_t pid : pids_) {
    int res = kill_(pid, SIGKILL);
    DCHECK_EQ(res, 0);
  }
  return ScopedAStatus::ok();
}

ScopedAStatus ArtdCancellationSignal::getType(int64_t* _aidl_return) {
  *_aidl_return = reinterpret_cast<intptr_t>(kArtdCancellationSignalType);
  return ScopedAStatus::ok();
}

ScopedAStatus Artd::createCancellationSignal(
    std::shared_ptr<IArtdCancellationSignal>* _aidl_return) {
  *_aidl_return = ndk::SharedRefBase::make<ArtdCancellationSignal>(kill_);
  return ScopedAStatus::ok();
}

ScopedAStatus Artd::cleanup(const std::vector<ProfilePath>& in_profilesToKeep,
                            const std::vector<ArtifactsPath>& in_artifactsToKeep,
                            const std::vector<VdexPath>& in_vdexFilesToKeep,
                            int64_t* _aidl_return) {
  std::unordered_set<std::string> files_to_keep;
  for (const ProfilePath& profile : in_profilesToKeep) {
    files_to_keep.insert(OR_RETURN_FATAL(BuildProfileOrDmPath(profile)));
  }
  for (const ArtifactsPath& artifacts : in_artifactsToKeep) {
    std::string oat_path = OR_RETURN_FATAL(BuildOatPath(artifacts));
    files_to_keep.insert(OatPathToVdexPath(oat_path));
    files_to_keep.insert(OatPathToArtPath(oat_path));
    files_to_keep.insert(std::move(oat_path));
  }
  for (const VdexPath& vdex : in_vdexFilesToKeep) {
    files_to_keep.insert(OR_RETURN_FATAL(BuildVdexPath(vdex)));
  }
  *_aidl_return = 0;
  for (const std::string& file : OR_RETURN_NON_FATAL(ListManagedFiles())) {
    if (files_to_keep.find(file) == files_to_keep.end()) {
      LOG(INFO) << ART_FORMAT("Cleaning up obsolete file '{}'", file);
      *_aidl_return += GetSizeAndDeleteFile(file);
    }
  }
  return ScopedAStatus::ok();
}

ScopedAStatus Artd::isInDalvikCache(const std::string& in_dexFile, bool* _aidl_return) {
  // The artifacts should be in the global dalvik-cache directory if:
  // (1). the dex file is on a system partition, even if the partition is remounted read-write,
  //      or
  // (2). the dex file is in any other readonly location. (At the time of writing, this only
  //      include Incremental FS.)
  //
  // We cannot rely on access(2) because:
  // - It doesn't take effective capabilities into account, from which artd gets root access
  //   to the filesystem.
  // - The `faccessat` variant with the `AT_EACCESS` flag, which takes effective capabilities
  //   into account, is not supported by bionic.

  OR_RETURN_FATAL(ValidateDexPath(in_dexFile));

  std::vector<FstabEntry> entries = OR_RETURN_NON_FATAL(GetProcMountsEntriesForPath(in_dexFile));
  // The last one controls because `/proc/mounts` reflects the sequence of `mount`.
  for (auto it = entries.rbegin(); it != entries.rend(); it++) {
    if (it->fs_type == "overlay") {
      // Ignore the overlays created by `remount`.
      continue;
    }
    // We need to special-case Incremental FS since it is tagged as read-write while it's actually
    // not.
    *_aidl_return = (it->flags & MS_RDONLY) != 0 || it->fs_type == "incremental-fs";
    return ScopedAStatus::ok();
  }

  return NonFatal(ART_FORMAT("Fstab entries not found for '{}'", in_dexFile));
}

ScopedAStatus Artd::validateDexPath(const std::string& in_dexPath,
                                    std::optional<std::string>* _aidl_return) {
  if (Result<void> result = ValidateDexPath(in_dexPath); !result.ok()) {
    *_aidl_return = result.error().message();
  } else {
    *_aidl_return = std::nullopt;
  }
  return ScopedAStatus::ok();
}

ScopedAStatus Artd::validateClassLoaderContext(const std::string& in_dexPath,
                                               const std::string& in_classLoaderContext,
                                               std::optional<std::string>* _aidl_return) {
  if (in_classLoaderContext == ClassLoaderContext::kUnsupportedClassLoaderContextEncoding) {
    *_aidl_return = std::nullopt;
    return ScopedAStatus::ok();
  }

  std::unique_ptr<ClassLoaderContext> context = ClassLoaderContext::Create(in_classLoaderContext);
  if (context == nullptr) {
    *_aidl_return = ART_FORMAT("Class loader context '{}' is invalid", in_classLoaderContext);
    return ScopedAStatus::ok();
  }

  std::vector<std::string> flattened_context = context->FlattenDexPaths();
  std::string dex_dir = Dirname(in_dexPath);
  for (const std::string& context_element : flattened_context) {
    std::string context_path = std::filesystem::path(dex_dir).append(context_element);
    if (Result<void> result = ValidateDexPath(context_path); !result.ok()) {
      *_aidl_return = result.error().message();
      return ScopedAStatus::ok();
    }
  }

  *_aidl_return = std::nullopt;
  return ScopedAStatus::ok();
}

Result<void> Artd::Start() {
  OR_RETURN(SetLogVerbosity());

  ScopedAStatus status = ScopedAStatus::fromStatus(
      AServiceManager_registerLazyService(this->asBinder().get(), kServiceName));
  if (!status.isOk()) {
    return Error() << status.getDescription();
  }

  ABinderProcess_startThreadPool();

  return {};
}

Result<OatFileAssistantContext*> Artd::GetOatFileAssistantContext() {
  std::lock_guard<std::mutex> lock(ofa_context_mu_);

  if (ofa_context_ == nullptr) {
    ofa_context_ = std::make_unique<OatFileAssistantContext>(
        std::make_unique<OatFileAssistantContext::RuntimeOptions>(
            OatFileAssistantContext::RuntimeOptions{
                .image_locations = *OR_RETURN(GetBootImageLocations()),
                .boot_class_path = *OR_RETURN(GetBootClassPath()),
                .boot_class_path_locations = *OR_RETURN(GetBootClassPath()),
                .deny_art_apex_data_files = DenyArtApexDataFiles(),
            }));
    std::string error_msg;
    if (!ofa_context_->FetchAll(&error_msg)) {
      return Error() << error_msg;
    }
  }

  return ofa_context_.get();
}

Result<const std::vector<std::string>*> Artd::GetBootImageLocations() {
  std::lock_guard<std::mutex> lock(cache_mu_);

  if (!cached_boot_image_locations_.has_value()) {
    std::string location_str;

    if (UseJitZygoteLocked()) {
      location_str = GetJitZygoteBootImageLocation();
    } else if (std::string value = GetUserDefinedBootImageLocationsLocked(); !value.empty()) {
      location_str = std::move(value);
    } else {
      std::string error_msg;
      std::string android_root = GetAndroidRootSafe(&error_msg);
      if (!error_msg.empty()) {
        return Errorf("Failed to get ANDROID_ROOT: {}", error_msg);
      }
      location_str = GetDefaultBootImageLocation(android_root, DenyArtApexDataFilesLocked());
    }

    cached_boot_image_locations_ = Split(location_str, ":");
  }

  return &cached_boot_image_locations_.value();
}

Result<const std::vector<std::string>*> Artd::GetBootClassPath() {
  std::lock_guard<std::mutex> lock(cache_mu_);

  if (!cached_boot_class_path_.has_value()) {
    const char* env_value = getenv("BOOTCLASSPATH");
    if (env_value == nullptr || strlen(env_value) == 0) {
      return Errorf("Failed to get environment variable 'BOOTCLASSPATH'");
    }
    cached_boot_class_path_ = Split(env_value, ":");
  }

  return &cached_boot_class_path_.value();
}

bool Artd::UseJitZygote() {
  std::lock_guard<std::mutex> lock(cache_mu_);
  return UseJitZygoteLocked();
}

bool Artd::UseJitZygoteLocked() {
  if (!cached_use_jit_zygote_.has_value()) {
    cached_use_jit_zygote_ =
        props_->GetBool("persist.device_config.runtime_native_boot.profilebootclasspath",
                        "dalvik.vm.profilebootclasspath",
                        /*default_value=*/false);
  }

  return cached_use_jit_zygote_.value();
}

const std::string& Artd::GetUserDefinedBootImageLocations() {
  std::lock_guard<std::mutex> lock(cache_mu_);
  return GetUserDefinedBootImageLocationsLocked();
}

const std::string& Artd::GetUserDefinedBootImageLocationsLocked() {
  if (!cached_user_defined_boot_image_locations_.has_value()) {
    cached_user_defined_boot_image_locations_ = props_->GetOrEmpty("dalvik.vm.boot-image");
  }

  return cached_user_defined_boot_image_locations_.value();
}

bool Artd::DenyArtApexDataFiles() {
  std::lock_guard<std::mutex> lock(cache_mu_);
  return DenyArtApexDataFilesLocked();
}

bool Artd::DenyArtApexDataFilesLocked() {
  if (!cached_deny_art_apex_data_files_.has_value()) {
    cached_deny_art_apex_data_files_ =
        !props_->GetBool("odsign.verification.success", /*default_value=*/false);
  }

  return cached_deny_art_apex_data_files_.value();
}

Result<std::string> Artd::GetProfman() { return BuildArtBinPath("profman"); }

Result<std::string> Artd::GetArtExec() { return BuildArtBinPath("art_exec"); }

bool Artd::ShouldUseDex2Oat64() {
  return !props_->GetOrEmpty("ro.product.cpu.abilist64").empty() &&
         props_->GetBool("dalvik.vm.dex2oat64.enabled", /*default_value=*/false);
}

Result<std::string> Artd::GetDex2Oat() {
  std::string binary_name = ShouldUseDex2Oat64() ? "dex2oat64" : "dex2oat32";
  // TODO(b/234351700): Should we use the "d" variant?
  return BuildArtBinPath(binary_name);
}

bool Artd::ShouldCreateSwapFileForDexopt() {
  // Create a swap file by default. Dex2oat will decide whether to use it or not.
  return props_->GetBool("dalvik.vm.dex2oat-swap", /*default_value=*/true);
}

void Artd::AddBootImageFlags(/*out*/ CmdlineBuilder& args) {
  if (UseJitZygote()) {
    args.Add("--force-jit-zygote");
  } else {
    args.AddIfNonEmpty("--boot-image=%s", GetUserDefinedBootImageLocations());
  }
}

void Artd::AddCompilerConfigFlags(const std::string& instruction_set,
                                  const std::string& compiler_filter,
                                  PriorityClass priority_class,
                                  const DexoptOptions& dexopt_options,
                                  /*out*/ CmdlineBuilder& args) {
  args.Add("--instruction-set=%s", instruction_set);
  std::string features_prop = ART_FORMAT("dalvik.vm.isa.{}.features", instruction_set);
  args.AddIfNonEmpty("--instruction-set-features=%s", props_->GetOrEmpty(features_prop));
  std::string variant_prop = ART_FORMAT("dalvik.vm.isa.{}.variant", instruction_set);
  args.AddIfNonEmpty("--instruction-set-variant=%s", props_->GetOrEmpty(variant_prop));

  args.Add("--compiler-filter=%s", compiler_filter)
      .Add("--compilation-reason=%s", dexopt_options.compilationReason);

  args.AddIf(priority_class >= PriorityClass::INTERACTIVE, "--compact-dex-level=none");

  args.AddIfNonEmpty("--max-image-block-size=%s",
                     props_->GetOrEmpty("dalvik.vm.dex2oat-max-image-block-size"))
      .AddIfNonEmpty("--very-large-app-threshold=%s",
                     props_->GetOrEmpty("dalvik.vm.dex2oat-very-large"))
      .AddIfNonEmpty(
          "--resolve-startup-const-strings=%s",
          props_->GetOrEmpty("persist.device_config.runtime.dex2oat_resolve_startup_strings",
                             "dalvik.vm.dex2oat-resolve-startup-strings"));

  args.AddIf(dexopt_options.debuggable, "--debuggable")
      .AddIf(props_->GetBool("debug.generate-debug-info", /*default_value=*/false),
             "--generate-debug-info")
      .AddIf(props_->GetBool("dalvik.vm.dex2oat-minidebuginfo", /*default_value=*/false),
             "--generate-mini-debug-info");

  args.AddRuntimeIf(DenyArtApexDataFiles(), "-Xdeny-art-apex-data-files")
      .AddRuntime("-Xtarget-sdk-version:%d", dexopt_options.targetSdkVersion)
      .AddRuntimeIf(dexopt_options.hiddenApiPolicyEnabled, "-Xhidden-api-policy:enabled");
}

void Artd::AddPerfConfigFlags(PriorityClass priority_class,
                              /*out*/ CmdlineBuilder& art_exec_args,
                              /*out*/ CmdlineBuilder& dex2oat_args) {
  // CPU set and number of threads.
  std::string default_cpu_set_prop = "dalvik.vm.dex2oat-cpu-set";
  std::string default_threads_prop = "dalvik.vm.dex2oat-threads";
  std::string cpu_set;
  std::string threads;
  if (priority_class >= PriorityClass::BOOT) {
    cpu_set = props_->GetOrEmpty("dalvik.vm.boot-dex2oat-cpu-set");
    threads = props_->GetOrEmpty("dalvik.vm.boot-dex2oat-threads");
  } else if (priority_class >= PriorityClass::INTERACTIVE_FAST) {
    cpu_set = props_->GetOrEmpty("dalvik.vm.restore-dex2oat-cpu-set", default_cpu_set_prop);
    threads = props_->GetOrEmpty("dalvik.vm.restore-dex2oat-threads", default_threads_prop);
  } else if (priority_class <= PriorityClass::BACKGROUND) {
    cpu_set = props_->GetOrEmpty("dalvik.vm.background-dex2oat-cpu-set", default_cpu_set_prop);
    threads = props_->GetOrEmpty("dalvik.vm.background-dex2oat-threads", default_threads_prop);
  } else {
    cpu_set = props_->GetOrEmpty(default_cpu_set_prop);
    threads = props_->GetOrEmpty(default_threads_prop);
  }
  dex2oat_args.AddIfNonEmpty("--cpu-set=%s", cpu_set).AddIfNonEmpty("-j%s", threads);

  if (priority_class < PriorityClass::BOOT) {
    art_exec_args
        .Add(priority_class <= PriorityClass::BACKGROUND ? "--set-task-profile=Dex2OatBackground" :
                                                           "--set-task-profile=Dex2OatBootComplete")
        .Add("--set-priority=background");
  }

  dex2oat_args.AddRuntimeIfNonEmpty("-Xms%s", props_->GetOrEmpty("dalvik.vm.dex2oat-Xms"))
      .AddRuntimeIfNonEmpty("-Xmx%s", props_->GetOrEmpty("dalvik.vm.dex2oat-Xmx"));

  // Enable compiling dex files in isolation on low ram devices.
  // It takes longer but reduces the memory footprint.
  dex2oat_args.AddIf(props_->GetBool("ro.config.low_ram", /*default_value=*/false),
                     "--compile-individually");
}

Result<int> Artd::ExecAndReturnCode(const std::vector<std::string>& args,
                                    int timeout_sec,
                                    const ExecCallbacks& callbacks,
                                    ProcessStat* stat) const {
  std::string error_msg;
  ExecResult result =
      exec_utils_->ExecAndReturnResult(args, timeout_sec, callbacks, stat, &error_msg);
  if (result.status != ExecResult::kExited) {
    return Error() << error_msg;
  }
  return result.exit_code;
}

Result<struct stat> Artd::Fstat(const File& file) const {
  struct stat st;
  if (fstat_(file.Fd(), &st) != 0) {
    return Errorf("Unable to fstat file '{}'", file.GetPath());
  }
  return st;
}

}  // namespace artd
}  // namespace art