介绍
PackageManagerService（简称PKMS），是Android系统中核心服务之一，管理着所有跟package相关的工作，常见的有安装应用，卸载应用,应用信息查询。PKMS服务也是通过binder进行通信，IPackageManager.aidl由工具转换后自动生成binder的服务端IPackageManager.Stub和客户端IPackageManager.Stub.Proxy
Binder服务端：PackageManagerService继承于IPackageManager.Stub Binder客服端：ApplicationPackageManager（APM）是继承于PackageManager
PKMS的职责
- 负责Android系统中Package的安装，升级，卸载
- 对外提供统一的信息查询功能，其中包括查询系统中匹配的intent的activity，BroadCastReceiver或者Service等
PKMS启动过程
PKMS服务是在systemServer进程中启动的，它属于引导服务
private void startBootstrapServices(@NonNull TimingsTraceAndSlog t) {
...
t.traceBegin("StartInstaller");
Installer installer = mSystemServiceManager.startService(Installer.class);
t.traceEnd();
// Activity manager runs the show.
t.traceBegin("StartActivityManager");
// TODO: Might need to move after migration to WM.
ActivityTaskManagerService atm = mSystemServiceManager.startService(
ActivityTaskManagerService.Lifecycle.class).getService();
mActivityManagerService = ActivityManagerService.Lifecycle.startService(
mSystemServiceManager, atm);
mActivityManagerService.setSystemServiceManager(mSystemServiceManager);
mActivityManagerService.setInstaller(installer);
mWindowManagerGlobalLock = atm.getGlobalLock();
t.traceEnd();
// Start the package manager.
if (!mRuntimeRestart) {
FrameworkStatsLog.write(FrameworkStatsLog.BOOT_TIME_EVENT_ELAPSED_TIME_REPORTED,
FrameworkStatsLog
.BOOT_TIME_EVENT_ELAPSED_TIME__EVENT__PACKAGE_MANAGER_INIT_START,
SystemClock.elapsedRealtime());
}
t.traceBegin("StartPackageManagerService");
try {
Watchdog.getInstance().pauseWatchingCurrentThread("packagemanagermain");
mPackageManagerService = PackageManagerService.main(mSystemContext, installer,
mFactoryTestMode != FactoryTest.FACTORY_TEST_OFF, mOnlyCore);
} finally {
Watchdog.getInstance().resumeWatchingCurrentThread("packagemanagermain");
}
...
}
进入PackageManagerService类中的main方法
public static PackageManagerService main(Context context, Installer installer,
boolean factoryTest, boolean onlyCore) {
...
PackageManagerService m = new PackageManagerService(injector, onlyCore, factoryTest);
...
ServiceManager.addService("package", m);
final PackageManagerNative pmn = m.new PackageManagerNative();
ServiceManager.addService("package_native", pmn);
return m;
}
main方法主要做两件事
- 创建PackageManagerService并向ServiceManager注册
- 创建PackageManagerNative并向ServiceManager注册
PackageManagerService的构造方法的代码量很大，我们大致可以把它分为几个阶段
- 开始阶段 BOOT_PROGRESS_PMS_START
- 系统扫描阶段 BOOT_PROGRESS_PMS_SYSTEM_SCAN_START
- Data扫描阶段 BOOT_PROGRESS_PMS_DATA_SCAN_START
- 扫描结束 BOOT_PROGRESS_PMS_SCAN_END
- 就绪阶段 BOOT_PROGRESS_PMS_READY
开始阶段 BOOT_PROGRESS_PMS_START
public PackageManagerService(Injector injector, boolean onlyCore, boolean factoryTest) {
PackageManager.disableApplicationInfoCache();
PackageManager.disablePackageInfoCache();
PackageManager.corkPackageInfoCache();
//开始阶段日志
final TimingsTraceAndSlog t = new TimingsTraceAndSlog(TAG + "Timing",
Trace.TRACE_TAG_PACKAGE_MANAGER);
mPendingBroadcasts = new PendingPackageBroadcasts();
mInjector = injector;
mInjector.bootstrap(this);
mLock = injector.getLock();
mInstallLock = injector.getInstallLock();
LockGuard.installLock(mLock, LockGuard.INDEX_PACKAGES);
EventLog.writeEvent(EventLogTags.BOOT_PROGRESS_PMS_START,
SystemClock.uptimeMillis());
if (mSdkVersion <= 0) {
Slog.w(TAG, "**** ro.build.version.sdk not set!");
}
mContext = injector.getContext();
mFactoryTest = factoryTest;
mOnlyCore = onlyCore;
mMetrics = new DisplayMetrics();
mInstaller = injector.getInstaller();
// 创建提供服务或数据的子组件，注意创建的顺序很重要
t.traceBegin("createSubComponents");
// 暴露私有服务供系统组件调用
mPmInternal = new PackageManagerInternalImpl();
LocalServices.addService(PackageManagerInternal.class, mPmInternal);
mUserManager = injector.getUserManagerService();
mComponentResolver = injector.getComponentResolver();
mPermissionManager = injector.getPermissionManagerServiceInternal();
//settings是主要保存设置和信息的类
mSettings = injector.getSettings();
//权限管理类
mPermissionManagerService = (IPermissionManager) ServiceManager.getService("permissionmgr");
mIncrementalManager =
(IncrementalManager) mContext.getSystemService(Context.INCREMENTAL_SERVICE);
PlatformCompat platformCompat = mInjector.getCompatibility();
mPackageParserCallback = new PackageParser2.Callback() {
@Override
public boolean isChangeEnabled(long changeId, @NonNull ApplicationInfo appInfo) {
return platformCompat.isChangeEnabled(changeId, appInfo);
}
@Override
public boolean hasFeature(String feature) {
return PackageManagerService.this.hasSystemFeature(feature, 0);
}
};
// CHECKSTYLE:ON IndentationCheck
t.traceEnd();
t.traceBegin("addSharedUsers");
mSettings.addSharedUserLPw("android.uid.system", Process.SYSTEM_UID,
ApplicationInfo.FLAG_SYSTEM, ApplicationInfo.PRIVATE_FLAG_PRIVILEGED);
...
String separateProcesses = SystemProperties.get("debug.separate_processes");
if (separateProcesses != null && separateProcesses.length() > 0) {
if ("*".equals(separateProcesses)) {
mDefParseFlags = PackageParser.PARSE_IGNORE_PROCESSES;
mSeparateProcesses = null;
Slog.w(TAG, "Running with debug.separate_processes: * (ALL)");
} else {
mDefParseFlags = 0;
mSeparateProcesses = separateProcesses.split(",");
Slog.w(TAG, "Running with debug.separate_processes: "
+ separateProcesses);
}
} else {
mDefParseFlags = 0;
mSeparateProcesses = null;
}
//Dex优化类
mPackageDexOptimizer = new PackageDexOptimizer(mInstaller, mInstallLock, mContext,
"*dexopt*");
//Dex管理类
mDexManager =
new DexManager(mContext, this, mPackageDexOptimizer, mInstaller, mInstallLock);
mArtManagerService = new ArtManagerService(mContext, this, mInstaller, mInstallLock);
mMoveCallbacks = new MoveCallbacks(FgThread.get().getLooper());
mViewCompiler = new ViewCompiler(mInstallLock, mInstaller);
...
// CHECKSTYLE:OFF IndentationCheck
synchronized (mInstallLock) {
// writer
synchronized (mLock) {
//创建后台线程和handler
mHandlerThread = new ServiceThread(TAG,
Process.THREAD_PRIORITY_BACKGROUND, true /*allowIo*/);
mHandlerThread.start();
mHandler = new PackageHandler(mHandlerThread.getLooper());
mProcessLoggingHandler = new ProcessLoggingHandler();
Watchdog.getInstance().addThread(mHandler, WATCHDOG_TIMEOUT);
mInstantAppRegistry = new InstantAppRegistry(this);
ArrayMap<String, SystemConfig.SharedLibraryEntry> libConfig
= systemConfig.getSharedLibraries();
final int builtInLibCount = libConfig.size();
for (int i = 0; i < builtInLibCount; i++) {
String name = libConfig.keyAt(i);
SystemConfig.SharedLibraryEntry entry = libConfig.valueAt(i);
addBuiltInSharedLibraryLocked(entry.filename, name);
}
long undefinedVersion = SharedLibraryInfo.VERSION_UNDEFINED;
for (int i = 0; i < builtInLibCount; i++) {
String name = libConfig.keyAt(i);
SystemConfig.SharedLibraryEntry entry = libConfig.valueAt(i);
final int dependencyCount = entry.dependencies.length;
for (int j = 0; j < dependencyCount; j++) {
final SharedLibraryInfo dependency =
getSharedLibraryInfoLPr(entry.dependencies[j], undefinedVersion);
if (dependency != null) {
getSharedLibraryInfoLPr(name, undefinedVersion).addDependency(dependency);
}
}
}
SELinuxMMAC.readInstallPolicy();
t.traceBegin("loadFallbacks");
FallbackCategoryProvider.loadFallbacks();
t.traceEnd();
t.traceBegin("read user settings");
//解析系统配置文件package.xml
mFirstBoot = !mSettings.readLPw(mInjector.getUserManagerInternal().getUsers(false));
t.traceEnd();
//清理代码路径不存在的包，由bug/32321269引起
final int packageSettingCount = mSettings.mPackages.size();
for (int i = packageSettingCount - 1; i >= 0; i--) {
PackageSetting ps = mSettings.mPackages.valueAt(i);
if (!isExternal(ps) && (ps.codePath == null || !ps.codePath.exists())
&& mSettings.getDisabledSystemPkgLPr(ps.name) != null) {
mSettings.mPackages.removeAt(i);
mSettings.enableSystemPackageLPw(ps.name);
}
}
if (!mOnlyCore && mFirstBoot) {
requestCopyPreoptedFiles();
}
//自定义mCustomResolverComponentName
String customResolverActivityName = Resources.getSystem().getString(
R.string.config_customResolverActivity);
if (!TextUtils.isEmpty(customResolverActivityName)) {
mCustomResolverComponentName = ComponentName.unflattenFromString(
customResolverActivityName);
}
...
}
主要是对一些属性和子服务进行创建或赋值，其中比较重要的有mInstaller，mSettings，mPackageDexOptimizer等。在一起的版本中有些属性是直接new出来的，现在采用的是Injector的方法获取。另外还开启啦工作线程。
mSettings.readLPw()
boolean readLPw(@NonNull List<UserInfo> users) {
FileInputStream str = null;
//判断备份文件是否存在
if (mBackupSettingsFilename.exists()) {
try {
str = new FileInputStream(mBackupSettingsFilename);
mReadMessages.append("Reading from backup settings file\n");
PackageManagerService.reportSettingsProblem(Log.INFO,
"Need to read from backup settings file");
if (mSettingsFilename.exists()) {
//如果备份文件和常规文件同时存在，则忽略常规文件（常规文件是在异常时出现，而备份文件不是）
Slog.w(PackageManagerService.TAG, "Cleaning up settings file "
+ mSettingsFilename);
mSettingsFilename.delete();
}
} catch (java.io.IOException e) {
// We'll try for the normal settings file.
}
}
//把集合清空
mPendingPackages.clear();
mPastSignatures.clear();
mKeySetRefs.clear();
mInstallerPackages.clear();
try {
if (str == null) { //备份文件不存在
if (!mSettingsFilename.exists()) {//两者都不存在
mReadMessages.append("No settings file found\n");
PackageManagerService.reportSettingsProblem(Log.INFO,
"No settings file; creating initial state");
// It's enough to just touch version details to create them
// with default values
findOrCreateVersion(StorageManager.UUID_PRIVATE_INTERNAL).forceCurrent();
findOrCreateVersion(StorageManager.UUID_PRIMARY_PHYSICAL).forceCurrent();
return false;
}
str = new FileInputStream(mSettingsFilename);
}
XmlPullParser parser = Xml.newPullParser();
parser.setInput(str, StandardCharsets.UTF_8.name());
int type;
while ((type = parser.next()) != XmlPullParser.START_TAG
&& type != XmlPullParser.END_DOCUMENT) {
;
}
//xml文件不正常
if (type != XmlPullParser.START_TAG) {
mReadMessages.append("No start tag found in settings file\n");
PackageManagerService.reportSettingsProblem(Log.WARN,
"No start tag found in package manager settings");
Slog.wtf(PackageManagerService.TAG,
"No start tag found in package manager settings");
return false;
}
int outerDepth = parser.getDepth();
//解析xml
while ((type = parser.next()) != XmlPullParser.END_DOCUMENT
&& (type != XmlPullParser.END_TAG || parser.getDepth() > outerDepth)) {
if (type == XmlPullParser.END_TAG || type == XmlPullParser.TEXT) {
continue;
}
String tagName = parser.getName();
if (tagName.equals("package")) {
readPackageLPw(parser);
} else if (tagName.equals("permissions")) {
mPermissions.readPermissions(parser);
} else if (tagName.equals("permission-trees")) {
mPermissions.readPermissionTrees(parser);
} else if (tagName.equals("shared-user")) {
readSharedUserLPw(parser);
} else if ...
}
str.close();
} catch ...
...
return true;
}
readPackageLPw 读xml的元素和属性，获取包信息
private void readPackageLPw(XmlPullParser parser) throws XmlPullParserException, IOException {
String name = null;
String realName = null;
String idStr = null;
String sharedIdStr = null;
String codePathStr = null;
String resourcePathStr = null;
String legacyCpuAbiString = null;
String legacyNativeLibraryPathStr = null;
String primaryCpuAbiString = null;
String secondaryCpuAbiString = null;
String cpuAbiOverrideString = null;
String systemStr = null;
String installerPackageName = null;
String isOrphaned = null;
String installOriginatingPackageName = null;
String installInitiatingPackageName = null;
String installInitiatorUninstalled = null;
String volumeUuid = null;
String categoryHintString = null;
String updateAvailable = null;
int categoryHint = ApplicationInfo.CATEGORY_UNDEFINED;
String uidError = null;
int pkgFlags = 0;
int pkgPrivateFlags = 0;
long timeStamp = 0;
long firstInstallTime = 0;
long lastUpdateTime = 0;
PackageSetting packageSetting = null;
String version = null;
long versionCode = 0;
String installedForceQueryable = null;
try {
name = parser.getAttributeValue(null, ATTR_NAME);
realName = parser.getAttributeValue(null, "realName");
idStr = parser.getAttributeValue(null, "userId");
uidError = parser.getAttributeValue(null, "uidError");
sharedIdStr = parser.getAttributeValue(null, "sharedUserId");
codePathStr = parser.getAttributeValue(null, "codePath");
resourcePathStr = parser.getAttributeValue(null, "resourcePath");
...
if (name == null) {
PackageManagerService.reportSettingsProblem(Log.WARN,
"Error in package manager settings: <package> has no name at "
+ parser.getPositionDescription());
} else if (codePathStr == null) {
PackageManagerService.reportSettingsProblem(Log.WARN,
"Error in package manager settings: <package> has no codePath at "
+ parser.getPositionDescription());
} else if (userId > 0) {
packageSetting = addPackageLPw(name.intern(), realName, new File(codePathStr),
new File(resourcePathStr), legacyNativeLibraryPathStr, primaryCpuAbiString,
secondaryCpuAbiString, cpuAbiOverrideString, userId, versionCode, pkgFlags,
pkgPrivateFlags, null /*usesStaticLibraries*/,
null /*usesStaticLibraryVersions*/, null /*mimeGroups*/);
if (PackageManagerService.DEBUG_SETTINGS)
Log.i(PackageManagerService.TAG, "Reading package " + name + ": userId="
+ userId + " pkg=" + packageSetting);
if (packageSetting == null) {
PackageManagerService.reportSettingsProblem(Log.ERROR, "Failure adding uid "
+ userId + " while parsing settings at "
+ parser.getPositionDescription());
} else {
packageSetting.setTimeStamp(timeStamp);
packageSetting.firstInstallTime = firstInstallTime;
packageSetting.lastUpdateTime = lastUpdateTime;
}
} else if (sharedIdStr != null) {
if (sharedUserId > 0) {
packageSetting = new PackageSetting(name.intern(), realName, new File(
codePathStr), new File(resourcePathStr), legacyNativeLibraryPathStr,
primaryCpuAbiString, secondaryCpuAbiString, cpuAbiOverrideString,
versionCode, pkgFlags, pkgPrivateFlags, sharedUserId,
null /*usesStaticLibraries*/,
null /*usesStaticLibraryVersions*/,
null /*mimeGroups*/);
packageSetting.setTimeStamp(timeStamp);
packageSetting.firstInstallTime = firstInstallTime;
packageSetting.lastUpdateTime = lastUpdateTime;
mPendingPackages.add(packageSetting);
if (PackageManagerService.DEBUG_SETTINGS)
Log.i(PackageManagerService.TAG, "Reading package " + name
+ ": sharedUserId=" + sharedUserId + " pkg=" + packageSetting);
} else {
PackageManagerService.reportSettingsProblem(Log.WARN,
"Error in package manager settings: package " + name
+ " has bad sharedId " + sharedIdStr + " at "
+ parser.getPositionDescription());
}
} else {
PackageManagerService.reportSettingsProblem(Log.WARN,
"Error in package manager settings: package " + name + " has bad userId "
+ idStr + " at " + parser.getPositionDescription());
}
} catch (NumberFormatException e) {
PackageManagerService.reportSettingsProblem(Log.WARN,
"Error in package manager settings: package " + name + " has bad userId "
+ idStr + " at " + parser.getPositionDescription());
}
if (packageSetting != null) {
packageSetting.uidError = "true".equals(uidError);
InstallSource installSource = InstallSource.create(
installInitiatingPackageName, installOriginatingPackageName,
installerPackageName, "true".equals(isOrphaned),
"true".equals(installInitiatorUninstalled));
//packageSetting赋值
packageSetting.installSource = installSource;
packageSetting.volumeUuid = volumeUuid;
packageSetting.categoryHint = categoryHint;
packageSetting.legacyNativeLibraryPathString = legacyNativeLibraryPathStr;
packageSetting.primaryCpuAbiString = primaryCpuAbiString;
packageSetting.secondaryCpuAbiString = secondaryCpuAbiString;
packageSetting.updateAvailable = "true".equals(updateAvailable);
packageSetting.forceQueryableOverride = "true".equals(installedForceQueryable);
// Handle legacy string here for single-user mode
final String enabledStr = parser.getAttributeValue(null, ATTR_ENABLED);
if (enabledStr != null) {
try {
packageSetting.setEnabled(Integer.parseInt(enabledStr), 0 /* userId */, null);
} catch (NumberFormatException e) {
if (enabledStr.equalsIgnoreCase("true")) {
packageSetting.setEnabled(COMPONENT_ENABLED_STATE_ENABLED, 0, null);
} else if (enabledStr.equalsIgnoreCase("false")) {
packageSetting.setEnabled(COMPONENT_ENABLED_STATE_DISABLED, 0, null);
} else if (enabledStr.equalsIgnoreCase("default")) {
packageSetting.setEnabled(COMPONENT_ENABLED_STATE_DEFAULT, 0, null);
} else {
PackageManagerService.reportSettingsProblem(Log.WARN,
"Error in package manager settings: package " + name
+ " has bad enabled value: " + idStr + " at "
+ parser.getPositionDescription());
}
}
} else {
packageSetting.setEnabled(COMPONENT_ENABLED_STATE_DEFAULT, 0, null);
}
addInstallerPackageNames(installSource);
int outerDepth = parser.getDepth();
int type;
while ((type = parser.next()) != XmlPullParser.END_DOCUMENT
&& (type != XmlPullParser.END_TAG || parser.getDepth() > outerDepth)) {
if (type == XmlPullParser.END_TAG || type == XmlPullParser.TEXT) {
continue;
}
String tagName = parser.getName();
// Legacy
if (tagName.equals(TAG_DISABLED_COMPONENTS)) {
readDisabledComponentsLPw(packageSetting, parser, 0);
} else if (tagName.equals(TAG_ENABLED_COMPONENTS)) {
readEnabledComponentsLPw(packageSetting, parser, 0);
} else if (tagName.equals("sigs")) {
packageSetting.signatures.readXml(parser, mPastSignatures);
} else if (tagName.equals(TAG_PERMISSIONS)) {
readInstallPermissionsLPr(parser,
packageSetting.getPermissionsState());
packageSetting.installPermissionsFixed = true;
} else if (tagName.equals("proper-signing-keyset")) {
long id = Long.parseLong(parser.getAttributeValue(null, "identifier"));
Integer refCt = mKeySetRefs.get(id);
if (refCt != null) {
mKeySetRefs.put(id, refCt + 1);
} else {
mKeySetRefs.put(id, 1);
}
packageSetting.keySetData.setProperSigningKeySet(id);
} else if (tagName.equals("signing-keyset")) {
// from v1 of keysetmanagerservice - no longer used
} else if (tagName.equals("upgrade-keyset")) {
long id = Long.parseLong(parser.getAttributeValue(null, "identifier"));
packageSetting.keySetData.addUpgradeKeySetById(id);
} else if (tagName.equals("defined-keyset")) {
long id = Long.parseLong(parser.getAttributeValue(null, "identifier"));
String alias = parser.getAttributeValue(null, "alias");
Integer refCt = mKeySetRefs.get(id);
if (refCt != null) {
mKeySetRefs.put(id, refCt + 1);
} else {
mKeySetRefs.put(id, 1);
}
packageSetting.keySetData.addDefinedKeySet(id, alias);
} else if (tagName.equals("install-initiator-sigs")) {
final PackageSignatures signatures = new PackageSignatures();
signatures.readXml(parser, mPastSignatures);
packageSetting.installSource =
packageSetting.installSource.setInitiatingPackageSignatures(signatures);
} else if (tagName.equals(TAG_DOMAIN_VERIFICATION)) {
readDomainVerificationLPw(parser, packageSetting);
} else if (tagName.equals(TAG_MIME_GROUP)) {
packageSetting.mimeGroups = readMimeGroupLPw(parser, packageSetting.mimeGroups);
} else {
PackageManagerService.reportSettingsProblem(Log.WARN,
"Unknown element under <package>: " + parser.getName());
XmlUtils.skipCurrentTag(parser);
}
}
} else {
XmlUtils.skipCurrentTag(parser);
}
}
进入addPackageLPw方法
PackageSetting addPackageLPw(String name, String realName, File codePath, File resourcePath,
String legacyNativeLibraryPathString, String primaryCpuAbiString,
String secondaryCpuAbiString, String cpuAbiOverrideString, int uid, long vc, int
pkgFlags, int pkgPrivateFlags, String[] usesStaticLibraries,
long[] usesStaticLibraryNames, Map<String, ArraySet<String>> mimeGroups) {
PackageSetting p = mPackages.get(name);
if (p != null) {
if (p.appId == uid) {
return p;
}
PackageManagerService.reportSettingsProblem(Log.ERROR,
"Adding duplicate package, keeping first: " + name);
return null;
}
p = new PackageSetting(name, realName, codePath, resourcePath,
legacyNativeLibraryPathString, primaryCpuAbiString, secondaryCpuAbiString,
cpuAbiOverrideString, vc, pkgFlags, pkgPrivateFlags,
0 /*userId*/, usesStaticLibraries, usesStaticLibraryNames,
mimeGroups);
p.appId = uid;
if (registerExistingAppIdLPw(uid, p, name)) {
mPackages.put(name, p);
return p;
}
return null;
}
至此，大致知道了开始阶段的主要工作
- 初始化PMS的各个子组件/子服务以及相关属性
- 解析package.xml,获取已经安装的app信息存储到settings的mPackage中
- 创建后台工作线程和handler
系统扫描阶段 BOOT_PROGRESS_PMS_SYSTEM_SCAN_START
public PackageManagerService(Injector injector, boolean onlyCore, boolean factoryTest) {
...
//找到扫描的路径
final List<ScanPartition> scanPartitions = new ArrayList<>();
final List<ApexManager.ActiveApexInfo> activeApexInfos = mApexManager.getActiveApexInfos();
for (int i = 0; i < activeApexInfos.size(); i++) {
final ScanPartition scanPartition = resolveApexToScanPartition(activeApexInfos.get(i));
if (scanPartition != null) {
scanPartitions.add(scanPartition);
}
}
mDirsToScanAsSystem = new ArrayList<>();
mDirsToScanAsSystem.addAll(SYSTEM_PARTITIONS);
mDirsToScanAsSystem.addAll(scanPartitions);
...
EventLog.writeEvent(EventLogTags.BOOT_PROGRESS_PMS_SYSTEM_SCAN_START,
startTime);
final String bootClassPath = System.getenv("BOOTCLASSPATH");
final String systemServerClassPath = System.getenv("SYSTEMSERVERCLASSPATH");
if (bootClassPath == null) {
Slog.w(TAG, "No BOOTCLASSPATH found!");
}
if (systemServerClassPath == null) {
Slog.w(TAG, "No SYSTEMSERVERCLASSPATH found!");
}
File frameworkDir = new File(Environment.getRootDirectory(), "framework");
final VersionInfo ver = mSettings.getInternalVersion();
mIsUpgrade = !Build.FINGERPRINT.equals(ver.fingerprint);
if (mIsUpgrade) {
logCriticalInfo(Log.INFO,
"Upgrading from " + ver.fingerprint + " to " + Build.FINGERPRINT);
}
// 从 pre-M 升级时，将系统应用程序权限从安装提升到运行时
mPromoteSystemApps =
mIsUpgrade && ver.sdkVersion <= Build.VERSION_CODES.LOLLIPOP_MR1;
// 从 pre-N 升级时，我们需要像首次启动一样处理获取包信息，因为没有可用的分析数据。
mIsPreNUpgrade = mIsUpgrade && ver.sdkVersion < Build.VERSION_CODES.N;
mIsPreNMR1Upgrade = mIsUpgrade && ver.sdkVersion < Build.VERSION_CODES.N_MR1;
mIsPreQUpgrade = mIsUpgrade && ver.sdkVersion < Build.VERSION_CODES.Q;
//在扫描之前保存预先存在的包的名称，以便我们可以确定哪些系统包是由于升级而全新的。
if (isDeviceUpgrading()) {
mExistingPackages = new ArraySet<>(mSettings.mPackages.size());
for (PackageSetting ps : mSettings.mPackages.values()) {
mExistingPackages.add(ps.name);
}
}
mCacheDir = preparePackageParserCache();
// 设置标志以在扫描安装目录时监控而不更改 apk 文件路径。
int scanFlags = SCAN_BOOTING | SCAN_INITIAL;
if (mIsUpgrade || mFirstBoot) {
scanFlags = scanFlags | SCAN_FIRST_BOOT_OR_UPGRADE;
}
final int systemParseFlags = mDefParseFlags | PackageParser.PARSE_IS_SYSTEM_DIR;
final int systemScanFlags = scanFlags | SCAN_AS_SYSTEM;
PackageParser2 packageParser = new PackageParser2(mSeparateProcesses, mOnlyCore,
mMetrics, mCacheDir, mPackageParserCallback);
ExecutorService executorService = ParallelPackageParser.makeExecutorService();
mApexManager.scanApexPackagesTraced(packageParser, executorService);
//主要扫描代码
for (int i = mDirsToScanAsSystem.size() - 1; i >= 0; i--) {
final ScanPartition partition = mDirsToScanAsSystem.get(i);
if (partition.getOverlayFolder() == null) {
continue;
}
scanDirTracedLI(partition.getOverlayFolder(), systemParseFlags,
systemScanFlags | partition.scanFlag, 0,
packageParser, executorService);
}
scanDirTracedLI(frameworkDir, systemParseFlags,
systemScanFlags | SCAN_NO_DEX | SCAN_AS_PRIVILEGED, 0,
packageParser, executorService);
if (!mPackages.containsKey("android")) {
throw new IllegalStateException(
"Failed to load frameworks package; check log for warnings");
}
for (int i = 0, size = mDirsToScanAsSystem.size(); i < size; i++) {
final ScanPartition partition = mDirsToScanAsSystem.get(i);
if (partition.getPrivAppFolder() != null) {
scanDirTracedLI(partition.getPrivAppFolder(), systemParseFlags,
systemScanFlags | SCAN_AS_PRIVILEGED | partition.scanFlag, 0,
packageParser, executorService);
}
scanDirTracedLI(partition.getAppFolder(), systemParseFlags,
systemScanFlags | partition.scanFlag, 0,
packageParser, executorService);
}
mOverlayConfig = OverlayConfig.initializeSystemInstance(
consumer -> mPmInternal.forEachPackage(
pkg -> consumer.accept(pkg, pkg.isSystem())));
//收集可能不存在的系统app
final List<String> possiblyDeletedUpdatedSystemApps = new ArrayList<>();
final List<String> stubSystemApps = new ArrayList<>();
if (!mOnlyCore) {
// do this first before mucking with mPackages for the "expecting better" case
final Iterator<AndroidPackage> pkgIterator = mPackages.values().iterator();
while (pkgIterator.hasNext()) {
final AndroidPackage pkg = pkgIterator.next();
if (pkg.isStub()) {
stubSystemApps.add(pkg.getPackageName());
}
}
final Iterator<PackageSetting> psit = mSettings.mPackages.values().iterator();
//比较mSetting，mpackages（package.xml读取的记录）和mPackgaes（实时扫描的记录），看看是否有变化，有变化的情况往往是通过OTA升级
while (psit.hasNext()) {
PackageSetting ps = psit.next();
//非系统app跳过
if ((ps.pkgFlags & ApplicationInfo.FLAG_SYSTEM) == 0) {
continue;
}
final AndroidPackage scannedPkg = mPackages.get(ps.name);
if (scannedPkg != null) {
if (mSettings.isDisabledSystemPackageLPr(ps.name)) {
logCriticalInfo(Log.WARN,
"Expecting better updated system app for " + ps.name
+ "; removing system app. Last known"
+ " codePath=" + ps.codePathString
+ ", versionCode=" + ps.versionCode
+ "; scanned versionCode=" + scannedPkg.getLongVersionCode());
removePackageLI(scannedPkg, true);
mExpectingBetter.put(ps.name, ps.codePath);
}
continue;
}
if (!mSettings.isDisabledSystemPackageLPr(ps.name)) {
psit.remove();
logCriticalInfo(Log.WARN, "System package " + ps.name
+ " no longer exists; it's data will be wiped");
mPermissionManager.updatePermissions(ps.name, null);
} else {
final PackageSetting disabledPs =
mSettings.getDisabledSystemPkgLPr(ps.name);
if (disabledPs.codePath == null || !disabledPs.codePath.exists()
|| disabledPs.pkg == null) {
possiblyDeletedUpdatedSystemApps.add(ps.name);
} else {
mExpectingBetter.put(disabledPs.name, disabledPs.codePath);
}
}
}
}
final int cachedSystemApps = PackageCacher.sCachedPackageReadCount.get();
mSettings.pruneSharedUsersLPw();
final long systemScanTime = SystemClock.uptimeMillis() - startTime;
final int systemPackagesCount = mPackages.size();
Slog.i(TAG, "Finished scanning system apps. Time: " + systemScanTime
+ " ms, packageCount: " + systemPackagesCount
+ " , timePerPackage: "
+ (systemPackagesCount == 0 ? 0 : systemScanTime / systemPackagesCount)
+ " , cached: " + cachedSystemApps);
if (mIsUpgrade && systemPackagesCount > 0) {
//CHECKSTYLE:OFF IndentationCheck
FrameworkStatsLog.write(FrameworkStatsLog.BOOT_TIME_EVENT_DURATION_REPORTED,
BOOT_TIME_EVENT_DURATION__EVENT__OTA_PACKAGE_MANAGER_SYSTEM_APP_AVG_SCAN_TIME,
systemScanTime / systemPackagesCount);
//CHECKSTYLE:ON IndentationCheck
}
...
}
这里主要是对系统区进行扫描，扫描顺序
OverlayFolder ->frameworkDir ->privAppFolder->appFolder
进入扫描的方法scanDirTracedLI
private void scanDirTracedLI(File scanDir, final int parseFlags, int scanFlags,
long currentTime, PackageParser2 packageParser, ExecutorService executorService) {
Trace.traceBegin(TRACE_TAG_PACKAGE_MANAGER, "scanDir [" + scanDir.getAbsolutePath() + "]");
try {
scanDirLI(scanDir, parseFlags, scanFlags, currentTime, packageParser, executorService);
} finally {
Trace.traceEnd(TRACE_TAG_PACKAGE_MANAGER);
}
}
进入scanDirLI方法
private void scanDirLI(File scanDir, int parseFlags, int scanFlags, long currentTime,
PackageParser2 packageParser, ExecutorService executorService) {
final File[] files = scanDir.listFiles();
if (ArrayUtils.isEmpty(files)) {//空文件夹直接返回
Log.d(TAG, "No files in app dir " + scanDir);
return;
}
if (DEBUG_PACKAGE_SCANNING) {
Log.d(TAG, "Scanning app dir " + scanDir + " scanFlags=" + scanFlags
+ " flags=0x" + Integer.toHexString(parseFlags));
}
//将传进来的PackageParser2和executorService封装成ParallelPackageParser对象
ParallelPackageParser parallelPackageParser =
new ParallelPackageParser(packageParser, executorService);
// Submit files for parsing in parallel
int fileCount = 0;
for (File file : files) {
final boolean isPackage = (isApkFile(file) || file.isDirectory())
&& !PackageInstallerService.isStageName(file.getName());
if (!isPackage) {
// Ignore entries which are not packages
continue;
}
//解析包的关键代码
parallelPackageParser.submit(file, parseFlags);
fileCount++;
}
// 解析完成之后，取出结果进行处理
for (; fileCount > 0; fileCount--) {
ParallelPackageParser.ParseResult parseResult = parallelPackageParser.take();
Throwable throwable = parseResult.throwable;
int errorCode = PackageManager.INSTALL_SUCCEEDED;
if (throwable == null) {
// TODO(toddke): move lower in the scan chain
// Static shared libraries have synthetic package names
if (parseResult.parsedPackage.isStaticSharedLibrary()) {
renameStaticSharedLibraryPackage(parseResult.parsedPackage);
}
try {
addForInitLI(parseResult.parsedPackage, parseFlags, scanFlags,
currentTime, null);
} catch (PackageManagerException e) {
errorCode = e.error;
Slog.w(TAG, "Failed to scan " + parseResult.scanFile + ": " + e.getMessage());
}
} else if (throwable instanceof PackageParserException) {
PackageParserException e = (PackageParserException)
throwable;
errorCode = e.error;
Slog.w(TAG, "Failed to parse " + parseResult.scanFile + ": " + e.getMessage());
} else {
throw new IllegalStateException("Unexpected exception occurred while parsing "
+ parseResult.scanFile, throwable);
}
if ((scanFlags & SCAN_AS_APK_IN_APEX) != 0 && errorCode != INSTALL_SUCCEEDED) {
mApexManager.reportErrorWithApkInApex(scanDir.getAbsolutePath());
}
// 删除无效的用户app
if ((scanFlags & SCAN_AS_SYSTEM) == 0
&& errorCode != PackageManager.INSTALL_SUCCEEDED) {
logCriticalInfo(Log.WARN,
"Deleting invalid package at " + parseResult.scanFile);
removeCodePathLI(parseResult.scanFile);
}
}
}
主要的操作：
- 通过ParallelPackageParser解析扫描目录下的包
- 取出解析结果，执行addForInitLI
- 删除无效的用户app
解析的结果是Parsedpackage对象，它是一个继承自AndroidPackage的接口，实现类是PackageImpl。
进入addForInitLI方法
private AndroidPackage addForInitLI(ParsedPackage parsedPackage,
@ParseFlags int parseFlags, @ScanFlags int scanFlags, long currentTime,
@Nullable UserHandle user)
throws PackageManagerException {
...
//获取一个ScanResult对象
final ScanResult scanResult = scanPackageNewLI(parsedPackage, parseFlags, scanFlags
| SCAN_UPDATE_SIGNATURE, currentTime, user, null);
if (scanResult.success) {
synchronized (mLock) {
boolean appIdCreated = false;
try {
final String pkgName = scanResult.pkgSetting.name;
final Map<String, ReconciledPackage> reconcileResult = reconcilePackagesLocked(
new ReconcileRequest(
Collections.singletonMap(pkgName, scanResult),
mSharedLibraries,
mPackages,
Collections.singletonMap(
pkgName, getSettingsVersionForPackage(parsedPackage)),
Collections.singletonMap(pkgName,
getSharedLibLatestVersionSetting(scanResult))),
mSettings.mKeySetManagerService);
appIdCreated = optimisticallyRegisterAppId(scanResult);
commitReconciledScanResultLocked(
reconcileResult.get(pkgName), mUserManager.getUserIds());
} catch (PackageManagerException e) {
if (appIdCreated) {
cleanUpAppIdCreation(scanResult);
}
throw e;
}
}
}
if (shouldHideSystemApp) {
synchronized (mLock) {
mSettings.disableSystemPackageLPw(parsedPackage.getPackageName(), true);
}
}
return scanResult.pkgSetting.pkg;
}
进入commitReconciledScanResultLocked方法
private AndroidPackage commitReconciledScanResultLocked(
@NonNull ReconciledPackage reconciledPkg, int[] allUsers) {
...
commitPackageSettings(pkg, oldPkg, pkgSetting, scanFlags,
(parseFlags & PackageParser.PARSE_CHATTY) != 0 /*chatty*/, reconciledPkg);
...
return pkg;
}
进入commitPackageSettings方法
private void commitPackageSettings(AndroidPackage pkg,
@Nullable AndroidPackage oldPkg, PackageSetting pkgSetting,
final @ScanFlags int scanFlags, boolean chatty, ReconciledPackage reconciledPkg) {
final String pkgName = pkg.getPackageName();
//判断是不是自定义的ResolverComponentName
if (mCustomResolverComponentName != null &&
mCustomResolverComponentName.getPackageName().equals(pkg.getPackageName())) {
setUpCustomResolverActivity(pkg, pkgSetting);
}
if (pkg.getPackageName().equals("android")) {
synchronized (mLock) {
mPlatformPackage = pkg;
mAndroidApplication = pkg.toAppInfoWithoutState();
mAndroidApplication.flags = PackageInfoUtils.appInfoFlags(pkg, pkgSetting);
mAndroidApplication.privateFlags =
PackageInfoUtils.appInfoPrivateFlags(pkg, pkgSetting);
mAndroidApplication.initForUser(UserHandle.USER_SYSTEM);
if (!mResolverReplaced) {
mResolveActivity.applicationInfo = mAndroidApplication;
mResolveActivity.name = ResolverActivity.class.getName();
mResolveActivity.packageName = mAndroidApplication.packageName;
mResolveActivity.processName = "system:ui";
mResolveActivity.launchMode = ActivityInfo.LAUNCH_MULTIPLE;
mResolveActivity.documentLaunchMode = ActivityInfo.DOCUMENT_LAUNCH_NEVER;
mResolveActivity.flags = ActivityInfo.FLAG_EXCLUDE_FROM_RECENTS;
mResolveActivity.theme = R.style.Theme_Material_Dialog_Alert;
mResolveActivity.exported = true;
mResolveActivity.enabled = true;
mResolveActivity.resizeMode = ActivityInfo.RESIZE_MODE_RESIZEABLE;
mResolveActivity.configChanges = ActivityInfo.CONFIG_SCREEN_SIZE
| ActivityInfo.CONFIG_SMALLEST_SCREEN_SIZE
| ActivityInfo.CONFIG_SCREEN_LAYOUT
| ActivityInfo.CONFIG_ORIENTATION
| ActivityInfo.CONFIG_KEYBOARD
| ActivityInfo.CONFIG_KEYBOARD_HIDDEN;
mResolveInfo.activityInfo = mResolveActivity;
mResolveInfo.priority = 0;
mResolveInfo.preferredOrder = 0;
mResolveInfo.match = 0;
mResolveComponentName = new ComponentName(
mAndroidApplication.packageName, mResolveActivity.name);
}
}
}
...
Trace.traceBegin(TRACE_TAG_PACKAGE_MANAGER, "updateSettings");
synchronized (mLock) {
// 更新mSettings中的相关信息（包数据）
mSettings.insertPackageSettingLPw(pkgSetting, pkg);
// 把包信息储存到mPackages中
mPackages.put(pkg.getPackageName(), pkg);
if ((scanFlags & SCAN_AS_APK_IN_APEX) != 0) {
mApexManager.registerApkInApex(pkg);
}
// 把KeySets添加到KeySetManagerService
KeySetManagerService ksms = mSettings.mKeySetManagerService;
ksms.addScannedPackageLPw(pkg);
//向mComponentResolver注册
mComponentResolver.addAllComponents(pkg, chatty);
final boolean isReplace =
reconciledPkg.prepareResult != null && reconciledPkg.prepareResult.replace;
//向mAppsFilter注册
mAppsFilter.addPackage(pkgSetting, isReplace);
// 不让临时应用程序定义新的权限
if ((scanFlags & SCAN_AS_INSTANT_APP) != 0) {
Slog.w(TAG, "Permission groups from package " + pkg.getPackageName()
+ " ignored: instant apps cannot define new permission groups.");
} else {
//权限相关处理
mPermissionManager.addAllPermissionGroups(pkg, chatty);
}
// 不允许临时应用程序定义新权限。
if ((scanFlags & SCAN_AS_INSTANT_APP) != 0) {
Slog.w(TAG, "Permissions from package " + pkg.getPackageName()
+ " ignored: instant apps cannot define new permissions.");
} else {
//权限相关处理
mPermissionManager.addAllPermissions(pkg, chatty);
}
int collectionSize = ArrayUtils.size(pkg.getInstrumentations());
StringBuilder r = null;
int i;
for (i = 0; i < collectionSize; i++) {
ParsedInstrumentation a = pkg.getInstrumentations().get(i);
a.setPackageName(pkg.getPackageName());
//向mInstrumentation注册
mInstrumentation.put(a.getComponentName(), a);
if (chatty) {
if (r == null) {
r = new StringBuilder(256);
} else {
r.append(' ');
}
r.append(a.getName());
}
}
if (r != null) {
if (DEBUG_PACKAGE_SCANNING) Log.d(TAG, " Instrumentation: " + r);
}
if (!pkg.getProtectedBroadcasts().isEmpty()) {
synchronized (mProtectedBroadcasts) {
mProtectedBroadcasts.addAll(pkg.getProtectedBroadcasts());
}
}
if (oldPkg != null) {
final ArrayList<String> allPackageNames = new ArrayList<>(mPackages.keySet());
AsyncTask.execute(() ->
mPermissionManager.revokeRuntimePermissionsIfGroupChanged(pkg, oldPkg,
allPackageNames));
}
}
Trace.traceEnd(TRACE_TAG_PACKAGE_MANAGER);
}
把解析的结果存储到PMS的各个相关变量中。
BOOT_PROGRESS_PMS_SYSTEM_SCAN_START阶段所做的事：
- 扫描各个旭通分区的app
- 解析系统app信息
- 把解析结果存储起来，存在在PMS的相关属性和Msettings里
Data扫描阶段 BOOT_PROGRESS_PMS_DATA_SCAN_START
public PackageManagerService(Injector injector, boolean onlyCore, boolean factoryTest) {
...
if (!mOnlyCore) {
EventLog.writeEvent(EventLogTags.BOOT_PROGRESS_PMS_DATA_SCAN_START,
SystemClock.uptimeMillis());
//扫描用户安装的app，/data/app目录
scanDirTracedLI(sAppInstallDir, 0, scanFlags | SCAN_REQUIRE_KNOWN, 0,
packageParser, executorService);
}
//关闭packageParser
packageParser.close();
List<Runnable> unfinishedTasks = executorService.shutdownNow();
if (!unfinishedTasks.isEmpty()) {
throw new IllegalStateException("Not all tasks finished before calling close: "
+ unfinishedTasks);
}
if (!mOnlyCore) {
//删除OTA升级中移除的系统app，如果ota对这个app的操作是删除，则完全删除app相关的东西，否则剥夺它系统app的身份
for (int i = possiblyDeletedUpdatedSystemApps.size() - 1; i >= 0; --i) {
final String packageName = possiblyDeletedUpdatedSystemApps.get(i);
final AndroidPackage pkg = mPackages.get(packageName);
final String msg;
//从disabled清单删除
mSettings.removeDisabledSystemPackageLPw(packageName);
if (pkg == null) {
msg = "Updated system package " + packageName
+ " no longer exists; removing its data";
} else {
msg = "Updated system package " + packageName
+ " no longer exists; rescanning package on data";
removePackageLI(pkg, true);
try {
final File codePath = new File(pkg.getCodePath());
scanPackageTracedLI(codePath, 0, scanFlags, 0, null);
} catch (PackageManagerException e) {
Slog.e(TAG, "Failed to parse updated, ex-system package: "
+ e.getMessage());
}
}
final PackageSetting ps = mSettings.mPackages.get(packageName);
if (ps != null && mPackages.get(packageName) == null) {
removePackageDataLIF(ps, null, null, 0, false);
}
logCriticalInfo(Log.WARN, msg);
}
for (int i = 0; i < mExpectingBetter.size(); i++) {
final String packageName = mExpectingBetter.keyAt(i);
if (!mPackages.containsKey(packageName)) {
final File scanFile = mExpectingBetter.valueAt(i);
logCriticalInfo(Log.WARN, "Expected better " + packageName
+ " but never showed up; reverting to system");
@ParseFlags int reparseFlags = 0;
@ScanFlags int rescanFlags = 0;
for (int i1 = mDirsToScanAsSystem.size() - 1; i1 >= 0; i1--) {
final ScanPartition partition = mDirsToScanAsSystem.get(i1);
if (partition.containsPrivApp(scanFile)) {
reparseFlags = systemParseFlags;
rescanFlags = systemScanFlags | SCAN_AS_PRIVILEGED
| partition.scanFlag;
break;
}
if (partition.containsApp(scanFile)) {
reparseFlags = systemParseFlags;
rescanFlags = systemScanFlags | partition.scanFlag;
break;
}
}
if (rescanFlags == 0) {
Slog.e(TAG, "Ignoring unexpected fallback path " + scanFile);
continue;
}
mSettings.enableSystemPackageLPw(packageName);
try {
scanPackageTracedLI(scanFile, reparseFlags, rescanFlags, 0, null);
} catch (PackageManagerException e) {
Slog.e(TAG, "Failed to parse original system package: "
+ e.getMessage());
}
}
}
installSystemStubPackages(stubSystemApps, scanFlags);
final int cachedNonSystemApps = PackageCacher.sCachedPackageReadCount.get()
- cachedSystemApps;
final long dataScanTime = SystemClock.uptimeMillis() - systemScanTime - startTime;
final int dataPackagesCount = mPackages.size() - systemPackagesCount;
Slog.i(TAG, "Finished scanning non-system apps. Time: " + dataScanTime
+ " ms, packageCount: " + dataPackagesCount
+ " , timePerPackage: "
+ (dataPackagesCount == 0 ? 0 : dataScanTime / dataPackagesCount)
+ " , cached: " + cachedNonSystemApps);
if (mIsUpgrade && dataPackagesCount > 0) {
//CHECKSTYLE:OFF IndentationCheck
FrameworkStatsLog.write(
FrameworkStatsLog.BOOT_TIME_EVENT_DURATION_REPORTED,
BOOT_TIME_EVENT_DURATION__EVENT__OTA_PACKAGE_MANAGER_DATA_APP_AVG_SCAN_TIME,
dataScanTime / dataPackagesCount);
//CHECKSTYLE:OFF IndentationCheck
}
}
mExpectingBetter.clear();
mStorageManagerPackage = getStorageManagerPackageName();
mSetupWizardPackage = getSetupWizardPackageNameImpl();
mComponentResolver.fixProtectedFilterPriorities();
mDefaultTextClassifierPackage = getDefaultTextClassifierPackageName();
mSystemTextClassifierPackageName = getSystemTextClassifierPackageName();
mWellbeingPackage = getWellbeingPackageName();
mDocumenterPackage = getDocumenterPackageName();
mConfiguratorPackage = getDeviceConfiguratorPackageName();
mAppPredictionServicePackage = getAppPredictionServicePackageName();
mIncidentReportApproverPackage = getIncidentReportApproverPackageName();
mRetailDemoPackage = getRetailDemoPackageName();
updateAllSharedLibrariesLocked(null, null, Collections.unmodifiableMap(mPackages));
for (SharedUserSetting setting : mSettings.getAllSharedUsersLPw()) {
final List<String> changedAbiCodePath =
applyAdjustedAbiToSharedUser(setting, null /*scannedPackage*/,
mInjector.getAbiHelper().getAdjustedAbiForSharedUser(
setting.packages, null /*scannedPackage*/));
if (changedAbiCodePath != null && changedAbiCodePath.size() > 0) {
for (int i = changedAbiCodePath.size() - 1; i >= 0; --i) {
final String codePathString = changedAbiCodePath.get(i);
try {
mInstaller.rmdex(codePathString,
getDexCodeInstructionSet(getPreferredInstructionSet()));
} catch (InstallerException ignored) {
}
}
}
setting.fixSeInfoLocked();
setting.updateProcesses();
}
mPackageUsage.read(mSettings.mPackages);
mCompilerStats.read();
...
}
这里主要是对/data/app进行扫描，主要工作和系统扫描app目录是一样的，除此之外还做了一下扫尾工作。
扫描结束 BOOT_PROGRESS_PMS_SCAN_END
EventLog.writeEvent(EventLogTags.BOOT_PROGRESS_PMS_SCAN_END,
SystemClock.uptimeMillis());
Slog.i(TAG, "Time to scan packages: "
+ ((SystemClock.uptimeMillis()-startTime)/1000f)
+ " seconds");
//如果sdk版本发生啦变化（系统升级），重新对app进行授权
final boolean sdkUpdated = (ver.sdkVersion != mSdkVersion);
if (sdkUpdated) {
Slog.i(TAG, "Platform changed from " + ver.sdkVersion + " to "
+ mSdkVersion + "; regranting permissions for internal storage");
}
mPermissionManager.updateAllPermissions(
StorageManager.UUID_PRIVATE_INTERNAL, sdkUpdated);
ver.sdkVersion = mSdkVersion;
// 如果是首次启动或者从6.0以前的系统升级，初始化用户首选app
if (!mOnlyCore && (mPromoteSystemApps || mFirstBoot)) {
for (UserInfo user : mInjector.getUserManagerInternal().getUsers(true)) {
mSettings.applyDefaultPreferredAppsLPw(user.id);
primeDomainVerificationsLPw(user.id);
}
}
//为系统用户准备存储空间，因为settingsProvider和systemUi等核心系统app不可能等用户启动
final int storageFlags;
if (StorageManager.isFileEncryptedNativeOrEmulated()) {
storageFlags = StorageManager.FLAG_STORAGE_DE;
} else {
storageFlags = StorageManager.FLAG_STORAGE_DE | StorageManager.FLAG_STORAGE_CE;
}
List<String> deferPackages = reconcileAppsDataLI(StorageManager.UUID_PRIVATE_INTERNAL,
UserHandle.USER_SYSTEM, storageFlags, true /* migrateAppData */,
true /* onlyCoreApps */);
mPrepareAppDataFuture = SystemServerInitThreadPool.submit(() -> {
TimingsTraceLog traceLog = new TimingsTraceLog("SystemServerTimingAsync",
Trace.TRACE_TAG_PACKAGE_MANAGER);
traceLog.traceBegin("AppDataFixup");
try {
mInstaller.fixupAppData(StorageManager.UUID_PRIVATE_INTERNAL,
StorageManager.FLAG_STORAGE_DE | StorageManager.FLAG_STORAGE_CE);
} catch (InstallerException e) {
Slog.w(TAG, "Trouble fixing GIDs", e);
}
traceLog.traceEnd();
traceLog.traceBegin("AppDataPrepare");
if (deferPackages == null || deferPackages.isEmpty()) {
return;
}
int count = 0;
for (String pkgName : deferPackages) {
AndroidPackage pkg = null;
synchronized (mLock) {
PackageSetting ps = mSettings.getPackageLPr(pkgName);
if (ps != null && ps.getInstalled(UserHandle.USER_SYSTEM)) {
pkg = ps.pkg;
}
}
if (pkg != null) {
synchronized (mInstallLock) {
prepareAppDataAndMigrateLIF(pkg, UserHandle.USER_SYSTEM, storageFlags,
true /* maybeMigrateAppData */);
}
count++;
}
}
traceLog.traceEnd();
Slog.i(TAG, "Deferred reconcileAppsData finished " + count + " packages");
}, "prepareAppData");
// 如果是升级后第一次正常启动，需要清除代码缓存，但不会清除应用的配置文件
if (mIsUpgrade && !mOnlyCore) {
Slog.i(TAG, "Build fingerprint changed; clearing code caches");
for (int i = 0; i < mSettings.mPackages.size(); i++) {
final PackageSetting ps = mSettings.mPackages.valueAt(i);
if (Objects.equals(StorageManager.UUID_PRIVATE_INTERNAL, ps.volumeUuid)) {
// No apps are running this early, so no need to freeze
clearAppDataLIF(ps.pkg, UserHandle.USER_ALL,
FLAG_STORAGE_DE | FLAG_STORAGE_CE | FLAG_STORAGE_EXTERNAL
| Installer.FLAG_CLEAR_CODE_CACHE_ONLY
| Installer.FLAG_CLEAR_APP_DATA_KEEP_ART_PROFILES);
}
}
ver.fingerprint = Build.FINGERPRINT;
}
if (!mOnlyCore && mIsPreQUpgrade) {
Slog.i(TAG, "Whitelisting all existing apps to hide their icons");
int size = mSettings.mPackages.size();
for (int i = 0; i < size; i++) {
final PackageSetting ps = mSettings.mPackages.valueAt(i);
if ((ps.pkgFlags & ApplicationInfo.FLAG_SYSTEM) != 0) {
continue;
}
ps.disableComponentLPw(PackageManager.APP_DETAILS_ACTIVITY_CLASS_NAME,
UserHandle.USER_SYSTEM);
}
}
mPromoteSystemApps = false;
ver.databaseVersion = Settings.CURRENT_DATABASE_VERSION;
//把更新后的mSettings的相关信息写入package.xml等对应文件中
t.traceBegin("write settings");
mSettings.writeLPr();
t.traceEnd();
这个阶段主要做的事：
- 如果sdk版本发生了变化，重新对app进行授权
- 为系统核心服务准备存粗空间
- 如果是升级后的第一次正常启动，需要清除代码缓存，但不会清除应用的配置文件
- 把更新后的信息写入对应的xml文件中
就绪阶段 BOOT_PROGRESS_PMS_READY
EventLog.writeEvent(EventLogTags.BOOT_PROGRESS_PMS_READY,
SystemClock.uptimeMillis());
if (!mOnlyCore) {
mRequiredVerifierPackage = getRequiredButNotReallyRequiredVerifierLPr();
mRequiredInstallerPackage = getRequiredInstallerLPr();
mRequiredUninstallerPackage = getRequiredUninstallerLPr();
mIntentFilterVerifierComponent = getIntentFilterVerifierComponentNameLPr();
if (mIntentFilterVerifierComponent != null) {
mIntentFilterVerifier = new IntentVerifierProxy(mContext,
mIntentFilterVerifierComponent);
} else {
mIntentFilterVerifier = null;
}
mServicesExtensionPackageName = getRequiredServicesExtensionPackageLPr();
mSharedSystemSharedLibraryPackageName = getRequiredSharedLibraryLPr(
PackageManager.SYSTEM_SHARED_LIBRARY_SHARED,
SharedLibraryInfo.VERSION_UNDEFINED);
} else {
mRequiredVerifierPackage = null;
mRequiredInstallerPackage = null;
mRequiredUninstallerPackage = null;
mIntentFilterVerifierComponent = null;
mIntentFilterVerifier = null;
mServicesExtensionPackageName = null;
mSharedSystemSharedLibraryPackageName = null;
}
mRequiredPermissionControllerPackage = getRequiredPermissionControllerLPr();
mSettings.setPermissionControllerVersion(
getPackageInfo(mRequiredPermissionControllerPackage, 0,
UserHandle.USER_SYSTEM).getLongVersionCode());
final int[] userIds = UserManagerService.getInstance().getUserIds();
for (AndroidPackage pkg : mPackages.values()) {
if (pkg.isSystem()) {
continue;
}
for (int userId : userIds) {
final PackageSetting ps = getPackageSetting(pkg.getPackageName());
if (ps == null || !ps.getInstantApp(userId) || !ps.getInstalled(userId)) {
continue;
}
mInstantAppRegistry.addInstantAppLPw(userId, ps.appId);
}
}
final Supplier<PackageParser2> apexParserSupplier = () -> new PackageParser2(
mSeparateProcesses, mOnlyCore, mMetrics, null /* cacheDir */,
mPackageParserCallback);
//初始化PackageInstallerService
mInstallerService = new PackageInstallerService(mContext, this, apexParserSupplier);
final Pair<ComponentName, String> instantAppResolverComponent =
getInstantAppResolverLPr();
if (instantAppResolverComponent != null) {
if (DEBUG_INSTANT) {
Slog.d(TAG, "Set ephemeral resolver: " + instantAppResolverComponent);
}
mInstantAppResolverConnection = new InstantAppResolverConnection(
mContext, instantAppResolverComponent.first,
instantAppResolverComponent.second);
mInstantAppResolverSettingsComponent =
getInstantAppResolverSettingsLPr(instantAppResolverComponent.first);
} else {
mInstantAppResolverConnection = null;
mInstantAppResolverSettingsComponent = null;
}
updateInstantAppInstallerLocked(null);
//读取并更新dex文件的使用情况
final Map<Integer, List<PackageInfo>> userPackages = new HashMap<>();
for (int userId : userIds) {
userPackages.put(userId, getInstalledPackages(/*flags*/ 0, userId).getList());
}
mDexManager.load(userPackages);
if (mIsUpgrade) {
FrameworkStatsLog.write(
FrameworkStatsLog.BOOT_TIME_EVENT_DURATION_REPORTED,
BOOT_TIME_EVENT_DURATION__EVENT__OTA_PACKAGE_MANAGER_INIT_TIME,
SystemClock.uptimeMillis() - startTime);
}
} // synchronized (mLock)
} // synchronized (mInstallLock)
mModuleInfoProvider = new ModuleInfoProvider(mContext, this);
PackageManager.uncorkPackageInfoCache();
t.traceBegin("GC");
Runtime.getRuntime().gc();
t.traceEnd();
mInstaller.setWarnIfHeld(mLock);
PackageParser.readConfigUseRoundIcon(mContext.getResources());
mServiceStartWithDelay = SystemClock.uptimeMillis() + (60 * 1000L);
这个阶段也是对应一些属性进行赋值，最重要的是初始化了mInstallerService。
小结
获取PKMS
启动过程涉及到的核心文件
| 文件 | 功能 |
|---|---|
| /data/data/ | App数据目录 |
| /data/user/ | App数据目录 |
| /data/app/ | App安装目录 |
| /data/system/packages.xml | 所有安装App信息 |
| /data/system/packages-stopped.xml | 所有强制停止app信息 |
| /data/system/packages.list | 所有安装app信息 |
Android系统有很多目录可以存放app
| 目录 | App类别 |
|---|---|
| /vendor/overlay | 系统app |
| /system/framework | 系统app |
| /system/priv-app | 系统app |
| /system/app | 系统app |
| /vendor/priv-app | 系统app |
| /vendor/app | 系统app |
| /oem/app | 系统app |
| /data/app | 普通app |
| /data/app-private | 普通app |
关于apk的安装原理，卸载，还有apk打包相关的，准备放在下一篇博客，敬请期待
