Keep activities stopped while the lock screen is up.

Tell the activity manager when the lock screen is shown, so it
can keep itself (mostly) in sleep mode during this time, having
the foreground actvities remain in their stopped state.

Change-Id: I71c86d3298f23a98014d7ae36fd540c9df9a64e6

4 files changed, 98 insertions, 13 deletions

diff --git a/core/java/android/app/ActivityManagerNative.java b/core/java/android/app/ActivityManagerNative.java
index a3fdf3e..7e1589f 100644
--- a/core/java/android/app/ActivityManagerNative.java
+++ b/core/java/android/app/ActivityManagerNative.java
@@ -1000,7 +1000,7 @@ public abstract class ActivityManagerNative extends Binder implements IActivityM
             }
             return true;
         }
-        
+
         case GOING_TO_SLEEP_TRANSACTION: {
             data.enforceInterface(IActivityManager.descriptor);
             goingToSleep();
@@ -1015,6 +1015,13 @@ public abstract class ActivityManagerNative extends Binder implements IActivityM
             return true;
         }
 
+        case SET_LOCK_SCREEN_SHOWN_TRANSACTION: {
+            data.enforceInterface(IActivityManager.descriptor);
+            setLockScreenShown(data.readInt() != 0);
+            reply.writeNoException();
+            return true;
+        }
+
         case SET_DEBUG_APP_TRANSACTION: {
             data.enforceInterface(IActivityManager.descriptor);
             String pn = data.readString();
@@ -2912,6 +2919,17 @@ class ActivityManagerProxy implements IActivityManager
         data.recycle();
         reply.recycle();
     }
+    public void setLockScreenShown(boolean shown) throws RemoteException
+    {
+        Parcel data = Parcel.obtain();
+        Parcel reply = Parcel.obtain();
+        data.writeInterfaceToken(IActivityManager.descriptor);
+        data.writeInt(shown ? 1 : 0);
+        mRemote.transact(SET_LOCK_SCREEN_SHOWN_TRANSACTION, data, reply, 0);
+        reply.readException();
+        data.recycle();
+        reply.recycle();
+    }
     public void setDebugApp(
         String packageName, boolean waitForDebugger, boolean persistent)
         throws RemoteException
diff --git a/core/java/android/app/IActivityManager.java b/core/java/android/app/IActivityManager.java
index c71b186..3fc2280 100644
--- a/core/java/android/app/IActivityManager.java
+++ b/core/java/android/app/IActivityManager.java
@@ -205,7 +205,8 @@ public interface IActivityManager extends IInterface {
     // Note: probably don't want to allow applications access to these.
     public void goingToSleep() throws RemoteException;
     public void wakingUp() throws RemoteException;
-    
+    public void setLockScreenShown(boolean shown) throws RemoteException;
+
     public void unhandledBack() throws RemoteException;
     public ParcelFileDescriptor openContentUri(Uri uri) throws RemoteException;
     public void setDebugApp(
@@ -588,4 +589,5 @@ public interface IActivityManager extends IInterface {
     int GET_CURRENT_USER_TRANSACTION = IBinder.FIRST_CALL_TRANSACTION+144;
     int TARGET_TASK_AFFINITY_MATCHES_ACTIVITY_TRANSACTION = IBinder.FIRST_CALL_TRANSACTION+145;
     int NAVIGATE_UP_TO_TRANSACTION = IBinder.FIRST_CALL_TRANSACTION+146;
+    int SET_LOCK_SCREEN_SHOWN_TRANSACTION = IBinder.FIRST_CALL_TRANSACTION+147;
 }
diff --git a/policy/src/com/android/internal/policy/impl/KeyguardViewMediator.java b/policy/src/com/android/internal/policy/impl/KeyguardViewMediator.java
index 52fb875..5b9160d 100644
--- a/policy/src/com/android/internal/policy/impl/KeyguardViewMediator.java
+++ b/policy/src/com/android/internal/policy/impl/KeyguardViewMediator.java
@@ -567,6 +567,7 @@ public class KeyguardViewMediator implements KeyguardViewCallback,
         synchronized (KeyguardViewMediator.this) {
             if (mHidden != isHidden) {
                 mHidden = isHidden;
+                updateActivityLockScreenState();
                 adjustUserActivityLocked();
                 adjustStatusBarLocked();
             }
@@ -1162,6 +1163,14 @@ public class KeyguardViewMediator implements KeyguardViewCallback,
         }
     }
 
+    private void updateActivityLockScreenState() {
+        try {
+            ActivityManagerNative.getDefault().setLockScreenShown(
+                    mShowing && !mHidden);
+        } catch (RemoteException e) {
+        }
+    }
+
     /**
      * Handle message sent by {@link #showLocked}.
      * @see #SHOW
@@ -1173,6 +1182,7 @@ public class KeyguardViewMediator implements KeyguardViewCallback,
 
             mKeyguardViewManager.show();
             mShowing = true;
+            updateActivityLockScreenState();
             adjustUserActivityLocked();
             adjustStatusBarLocked();
             try {
@@ -1207,6 +1217,7 @@ public class KeyguardViewMediator implements KeyguardViewCallback,
 
             mKeyguardViewManager.hide();
             mShowing = false;
+            updateActivityLockScreenState();
             adjustUserActivityLocked();
             adjustStatusBarLocked();
         }
@@ -1324,6 +1335,7 @@ public class KeyguardViewMediator implements KeyguardViewCallback,
             if (DEBUG) Log.d(TAG, "handleVerifyUnlock");
             mKeyguardViewManager.verifyUnlock();
             mShowing = true;
+            updateActivityLockScreenState();
         }
     }
 
diff --git a/services/java/com/android/server/am/ActivityManagerService.java b/services/java/com/android/server/am/ActivityManagerService.java
index 0c2e6ac..e37adc7 100644
--- a/services/java/com/android/server/am/ActivityManagerService.java
+++ b/services/java/com/android/server/am/ActivityManagerService.java
@@ -697,6 +697,16 @@ public final class ActivityManagerService extends ActivityManagerNative
     boolean mSleeping = false;
 
     /**
+     * State of external calls telling us if the device is asleep.
+     */
+    boolean mWentToSleep = false;
+
+    /**
+     * State of external call telling us if the lock screen is shown.
+     */
+    boolean mLockScreenShown = false;
+
+    /**
      * Set if we are shutting down the system, similar to sleeping.
      */
     boolean mShuttingDown = false;
@@ -6656,17 +6666,26 @@ public final class ActivityManagerService extends ActivityManagerNative
     }
 
     public void goingToSleep() {
+        if (checkCallingPermission(android.Manifest.permission.DEVICE_POWER)
+                != PackageManager.PERMISSION_GRANTED) {
+            throw new SecurityException("Requires permission "
+                    + android.Manifest.permission.DEVICE_POWER);
+        }
+
         synchronized(this) {
-            mSleeping = true;
+            mWentToSleep = true;
             mWindowManager.setEventDispatching(false);
 
-            mMainStack.stopIfSleepingLocked();
+            if (!mSleeping) {
+                mSleeping = true;
+                mMainStack.stopIfSleepingLocked();
 
-            // Initialize the wake times of all processes.
-            checkExcessivePowerUsageLocked(false);
-            mHandler.removeMessages(CHECK_EXCESSIVE_WAKE_LOCKS_MSG);
-            Message nmsg = mHandler.obtainMessage(CHECK_EXCESSIVE_WAKE_LOCKS_MSG);
-            mHandler.sendMessageDelayed(nmsg, POWER_CHECK_DELAY);
+                // Initialize the wake times of all processes.
+                checkExcessivePowerUsageLocked(false);
+                mHandler.removeMessages(CHECK_EXCESSIVE_WAKE_LOCKS_MSG);
+                Message nmsg = mHandler.obtainMessage(CHECK_EXCESSIVE_WAKE_LOCKS_MSG);
+                mHandler.sendMessageDelayed(nmsg, POWER_CHECK_DELAY);
+            }
         }
     }
 
@@ -6726,12 +6745,40 @@ public final class ActivityManagerService extends ActivityManagerNative
         Binder.restoreCallingIdentity(origId);
     }
 
+    private void comeOutOfSleepIfNeededLocked() {
+        if (!mWentToSleep && !mLockScreenShown) {
+            if (mSleeping) {
+                mSleeping = false;
+                mMainStack.awakeFromSleepingLocked();
+                mMainStack.resumeTopActivityLocked(null);
+            }
+        }
+    }
+
     public void wakingUp() {
+        if (checkCallingPermission(android.Manifest.permission.DEVICE_POWER)
+                != PackageManager.PERMISSION_GRANTED) {
+            throw new SecurityException("Requires permission "
+                    + android.Manifest.permission.DEVICE_POWER);
+        }
+
         synchronized(this) {
+            mWentToSleep = false;
             mWindowManager.setEventDispatching(true);
-            mSleeping = false;
-            mMainStack.awakeFromSleepingLocked();
-            mMainStack.resumeTopActivityLocked(null);
+            comeOutOfSleepIfNeededLocked();
+        }
+    }
+
+    public void setLockScreenShown(boolean shown) {
+        if (checkCallingPermission(android.Manifest.permission.DEVICE_POWER)
+                != PackageManager.PERMISSION_GRANTED) {
+            throw new SecurityException("Requires permission "
+                    + android.Manifest.permission.DEVICE_POWER);
+        }
+
+        synchronized(this) {
+            mLockScreenShown = shown;
+            comeOutOfSleepIfNeededLocked();
         }
     }
 
@@ -8815,7 +8862,13 @@ public final class ActivityManagerService extends ActivityManagerNative
                 }
             }
         }
-        pw.println("  mSleeping=" + mSleeping + " mShuttingDown=" + mShuttingDown);
+        if (mSleeping || mWentToSleep || mLockScreenShown) {
+            pw.println("  mSleeping=" + mSleeping + " mWentToSleep=" + mWentToSleep
+                    + " mLockScreenShown " + mLockScreenShown);
+        }
+        if (mShuttingDown) {
+            pw.println("  mShuttingDown=" + mShuttingDown);
+        }
         if (mDebugApp != null || mOrigDebugApp != null || mDebugTransient
                 || mOrigWaitForDebugger) {
             pw.println("  mDebugApp=" + mDebugApp + "/orig=" + mOrigDebugApp