Introduce Background Activity Launch home mode (9268360c) · Commits · e / os / android_frameworks_base

services/core/java/com/android/server/wm/ActivityStarter.java

+26 −4

Original line number	Diff line number	Diff line
		@@ -1195,7 +1195,12 @@ class ActivityStarter {
		}
		}

		// Only allow app switching to be resumed if activity is not a restricted background
		// activity, otherwise any background activity started in background task can stop
		// home button protection mode.
		if (!restrictedBgActivity) {
		mService.onStartActivitySetDidAppSwitch();
		}
		mController.doPendingActivityLaunches(false);

		mLastStartActivityResult = startActivityUnchecked(r, sourceRecord, voiceSession,
		@@ -1260,6 +1265,20 @@ class ActivityStarter {
		return false;
		}

		// Always allow home application to start activities.
		if (mService.mHomeProcess != null && callingUid == mService.mHomeProcess.mUid) {
		if (DEBUG_ACTIVITY_STARTS) {
		Slog.d(TAG, "Activity start allowed for home app callingUid (" + callingUid + ")");
		}
		return false;
		}

		// App switching will be allowed if BAL app switching flag is not enabled, or if
		// its app switching rule allows it.
		// This is used to block background activity launch even if the app is still
		// visible to user after user clicking home button.
		final boolean appSwitchAllowed = mService.getBalAppSwitchesAllowed();

		// don't abort if the callingUid has a visible window or is a persistent system process
		final int callingUidProcState = mService.getUidState(callingUid);
		final boolean callingUidHasAnyVisibleWindow =
		@@ -1269,7 +1288,8 @@ class ActivityStarter {
		\|\| callingUidProcState == ActivityManager.PROCESS_STATE_BOUND_TOP;
		final boolean isCallingUidPersistentSystemProcess =
		callingUidProcState <= ActivityManager.PROCESS_STATE_PERSISTENT_UI;
		if (callingUidHasAnyVisibleWindow \|\| isCallingUidPersistentSystemProcess) {
		if ((appSwitchAllowed && callingUidHasAnyVisibleWindow)
		\|\| isCallingUidPersistentSystemProcess) {
		if (DEBUG_ACTIVITY_STARTS) {
		Slog.d(TAG, "Activity start allowed: callingUidHasAnyVisibleWindow = " + callingUid
		+ ", isCallingUidPersistentSystemProcess = "
		@@ -1295,6 +1315,7 @@ class ActivityStarter {
		\|\| realCallingUidProcState <= ActivityManager.PROCESS_STATE_PERSISTENT_UI;
		if (realCallingUid != callingUid) {
		// don't abort if the realCallingUid has a visible window
		// TODO(b/171459802): We should check appSwitchAllowed also
		if (realCallingUidHasAnyVisibleWindow) {
		if (DEBUG_ACTIVITY_STARTS) {
		Slog.d(TAG, "Activity start allowed: realCallingUid (" + realCallingUid
		@@ -1376,7 +1397,7 @@ class ActivityStarter {
		// don't abort if the callerApp or other processes of that uid are allowed in any way
		if (callerApp != null) {
		// first check the original calling process
		if (callerApp.areBackgroundActivityStartsAllowed()) {
		if (callerApp.areBackgroundActivityStartsAllowed(appSwitchAllowed)) {
		if (DEBUG_ACTIVITY_STARTS) {
		Slog.d(TAG, "Background activity start allowed: callerApp process (pid = "
		+ callerApp.getPid() + ", uid = " + callerAppUid + ") is allowed");
		@@ -1389,7 +1410,8 @@ class ActivityStarter {
		if (uidProcesses != null) {
		for (int i = uidProcesses.size() - 1; i >= 0; i--) {
		final WindowProcessController proc = uidProcesses.valueAt(i);
		if (proc != callerApp && proc.areBackgroundActivityStartsAllowed()) {
		if (proc != callerApp
		&& proc.areBackgroundActivityStartsAllowed(appSwitchAllowed)) {
		if (DEBUG_ACTIVITY_STARTS) {
		Slog.d(TAG,
		"Background activity start allowed: process " + proc.getPid()

services/core/java/com/android/server/wm/ActivityTaskManagerService.java

+39 −1

Original line number	Diff line number	Diff line
		@@ -160,9 +160,11 @@ import android.app.WindowConfiguration;
		import android.app.admin.DevicePolicyCache;
		import android.app.assist.AssistContent;
		import android.app.assist.AssistStructure;
		import android.app.compat.CompatChanges;
		import android.app.servertransaction.ClientTransaction;
		import android.app.servertransaction.EnterPipRequestedItem;
		import android.app.usage.UsageStatsManagerInternal;
		import android.compat.annotation.ChangeId;
		import android.content.ActivityNotFoundException;
		import android.content.ComponentName;
		import android.content.ContentResolver;
		@@ -341,6 +343,12 @@ public class ActivityTaskManagerService extends IActivityTaskManager.Stub {
		/** This activity is being relaunched due to a free-resize operation. */
		public static final int RELAUNCH_REASON_FREE_RESIZE = 2;

		/**
		* Apps are blocked from starting activities in the foreground after the user presses home.
		*/
		@ChangeId
		public static final long BLOCK_ACTIVITY_STARTS_AFTER_HOME = 159433730L;

		Context mContext;

		/**
		@@ -2626,8 +2634,35 @@ public class ActivityTaskManagerService extends IActivityTaskManager.Stub {
		throw new SecurityException(msg);
		}

		/**
		* Return true if app switch protection will be handled by background activity launch logic.
		*/
		boolean getBalAppSwitchesProtectionEnabled() {
		return CompatChanges.isChangeEnabled(BLOCK_ACTIVITY_STARTS_AFTER_HOME);
		}

		/**
		* Return true if app switching is allowed.
		*/
		boolean getBalAppSwitchesAllowed() {
		if (getBalAppSwitchesProtectionEnabled()) {
		// Apps no longer able to start BAL again until app switching is resumed.
		return mAppSwitchesAllowedTime == 0;
		} else {
		// Legacy behavior, BAL logic won't block app switching.
		return true;
		}
		}

		boolean checkAppSwitchAllowedLocked(int sourcePid, int sourceUid,
		int callingPid, int callingUid, String name) {

		// Background activity launch logic replaces app switching protection, so allow
		// apps to start activity here now.
		if (getBalAppSwitchesProtectionEnabled()) {
		return true;
		}

		if (mAppSwitchesAllowedTime < SystemClock.uptimeMillis()) {
		return true;
		}
		@@ -4647,9 +4682,12 @@ public class ActivityTaskManagerService extends IActivityTaskManager.Stub {
		mAppSwitchesAllowedTime = SystemClock.uptimeMillis() + APP_SWITCH_DELAY_TIME;
		mLastStopAppSwitchesTime = SystemClock.uptimeMillis();
		mDidAppSwitch = false;
		// If BAL app switching enabled, app switches are blocked not delayed.
		if (!getBalAppSwitchesProtectionEnabled()) {
		getActivityStartController().schedulePendingActivityLaunches(APP_SWITCH_DELAY_TIME);
		}
		}
		}

		@Override
		public void resumeAppSwitches() {

services/core/java/com/android/server/wm/WindowProcessController.java

+25 −21

Original line number	Diff line number	Diff line
		@@ -505,7 +505,10 @@ public class WindowProcessController extends ConfigurationContainer<Configuratio
		}
		}

		boolean areBackgroundActivityStartsAllowed() {
		boolean areBackgroundActivityStartsAllowed(boolean appSwitchAllowed) {
		// If app switching is not allowed, we ignore all the start activity grace period
		// exception so apps cannot start itself in onPause() after pressing home button.
		if (appSwitchAllowed) {
		// allow if any activity in the caller has either started or finished very recently, and
		// it must be started or finished after last stop app switches time.
		final long now = SystemClock.uptimeMillis();
		@@ -529,6 +532,7 @@ public class WindowProcessController extends ConfigurationContainer<Configuratio
		}

		}
		}
		// allow if the proc is instrumenting with background activity starts privs
		if (mInstrumentingWithBackgroundActivityStartPrivileges) {
		if (DEBUG_ACTIVITY_STARTS) {
		@@ -539,7 +543,7 @@ public class WindowProcessController extends ConfigurationContainer<Configuratio
		return true;
		}
		// allow if the caller has an activity in any foreground task
		if (hasActivityInVisibleTask()) {
		if (appSwitchAllowed && hasActivityInVisibleTask()) {
		if (DEBUG_ACTIVITY_STARTS) {
		Slog.d(TAG, "[WindowProcessController(" + mPid
		+ ")] Activity start allowed: process has activity in foreground task");