Merge "Adds Westworld logging of RescueParty reset events."
diff --git a/api/system-current.txt b/api/system-current.txt
index a4b3978..2935c4f 100644
--- a/api/system-current.txt
+++ b/api/system-current.txt
@@ -5662,7 +5662,7 @@
     ctor public NotificationAssistantService();
     method public final void adjustNotification(android.service.notification.Adjustment);
     method public final void adjustNotifications(java.util.List<android.service.notification.Adjustment>);
-    method public void onActionClicked(java.lang.String, android.app.Notification.Action, int);
+    method public void onActionInvoked(java.lang.String, android.app.Notification.Action, int);
     method public final android.os.IBinder onBind(android.content.Intent);
     method public void onNotificationDirectReplied(java.lang.String);
     method public android.service.notification.Adjustment onNotificationEnqueued(android.service.notification.StatusBarNotification);
diff --git a/api/test-current.txt b/api/test-current.txt
index 575875d..957f957 100644
--- a/api/test-current.txt
+++ b/api/test-current.txt
@@ -1275,7 +1275,7 @@
     ctor public NotificationAssistantService();
     method public final void adjustNotification(android.service.notification.Adjustment);
     method public final void adjustNotifications(java.util.List<android.service.notification.Adjustment>);
-    method public void onActionClicked(java.lang.String, android.app.Notification.Action, int);
+    method public void onActionInvoked(java.lang.String, android.app.Notification.Action, int);
     method public final android.os.IBinder onBind(android.content.Intent);
     method public void onNotificationDirectReplied(java.lang.String);
     method public android.service.notification.Adjustment onNotificationEnqueued(android.service.notification.StatusBarNotification);
diff --git a/core/java/android/provider/Settings.java b/core/java/android/provider/Settings.java
index 574ccaf..ee6e1ba 100644
--- a/core/java/android/provider/Settings.java
+++ b/core/java/android/provider/Settings.java
@@ -13772,6 +13772,7 @@
          * requires_targeting_p            (boolean)
          * max_squeeze_remeasure_attempts  (int)
          * edit_choices_before_sending     (boolean)
+         * show_in_heads_up                (boolean)
          * </pre>
          * @see com.android.systemui.statusbar.policy.SmartReplyConstants
          * @hide
diff --git a/core/java/android/service/notification/NotificationAssistantService.java b/core/java/android/service/notification/NotificationAssistantService.java
index fd2b0fa..63fd563 100644
--- a/core/java/android/service/notification/NotificationAssistantService.java
+++ b/core/java/android/service/notification/NotificationAssistantService.java
@@ -203,7 +203,7 @@
      * @param action the action that is just clicked
      * @param source the source that provided the action, e.g. SOURCE_FROM_APP
      */
-    public void onActionClicked(@NonNull String key, @NonNull Notification.Action action,
+    public void onActionInvoked(@NonNull String key, @NonNull Notification.Action action,
             @Source int source) {
     }
 
@@ -338,7 +338,7 @@
             args.arg1 = key;
             args.arg2 = action;
             args.argi2 = source;
-            mHandler.obtainMessage(MyHandler.MSG_ON_ACTION_CLICKED, args).sendToTarget();
+            mHandler.obtainMessage(MyHandler.MSG_ON_ACTION_INVOKED, args).sendToTarget();
         }
     }
 
@@ -349,7 +349,7 @@
         public static final int MSG_ON_NOTIFICATION_EXPANSION_CHANGED = 4;
         public static final int MSG_ON_NOTIFICATION_DIRECT_REPLY_SENT = 5;
         public static final int MSG_ON_SUGGESTED_REPLY_SENT = 6;
-        public static final int MSG_ON_ACTION_CLICKED = 7;
+        public static final int MSG_ON_ACTION_INVOKED = 7;
 
         public MyHandler(Looper looper) {
             super(looper, null, false);
@@ -419,13 +419,13 @@
                     onSuggestedReplySent(key, reply, source);
                     break;
                 }
-                case MSG_ON_ACTION_CLICKED: {
+                case MSG_ON_ACTION_INVOKED: {
                     SomeArgs args = (SomeArgs) msg.obj;
                     String key = (String) args.arg1;
                     Notification.Action action = (Notification.Action) args.arg2;
                     int source = args.argi2;
                     args.recycle();
-                    onActionClicked(key, action, source);
+                    onActionInvoked(key, action, source);
                     break;
                 }
             }
diff --git a/packages/ExtServices/src/android/ext/services/notification/Assistant.java b/packages/ExtServices/src/android/ext/services/notification/Assistant.java
index fab1bcc..838b88b 100644
--- a/packages/ExtServices/src/android/ext/services/notification/Assistant.java
+++ b/packages/ExtServices/src/android/ext/services/notification/Assistant.java
@@ -382,11 +382,11 @@
     }
 
     @Override
-    public void onActionClicked(@NonNull String key, @NonNull Notification.Action action,
+    public void onActionInvoked(@NonNull String key, @NonNull Notification.Action action,
             @Source int source) {
         if (DEBUG) {
             Log.d(TAG,
-                    "onActionClicked() called with: key = [" + key + "], action = [" + action.title
+                    "onActionInvoked() called with: key = [" + key + "], action = [" + action.title
                             + "], source = [" + source + "]");
         }
         mSmartActionsHelper.onActionClicked(key, action, source);
diff --git a/packages/SystemUI/res/values/config.xml b/packages/SystemUI/res/values/config.xml
index 7cc5524..476089a 100644
--- a/packages/SystemUI/res/values/config.xml
+++ b/packages/SystemUI/res/values/config.xml
@@ -454,6 +454,10 @@
          RemoteInput.Builder.setEditChoicesBeforeSending. -->
     <bool name="config_smart_replies_in_notifications_edit_choices_before_sending">false</bool>
 
+    <!-- Smart replies in notifications: Whether smart suggestions in notifications are enabled in
+         heads-up notifications.  -->
+    <bool name="config_smart_replies_in_notifications_show_in_heads_up">true</bool>
+
     <!-- Screenshot editing default activity.  Must handle ACTION_EDIT image/png intents.
          Blank sends the user to the Chooser first.
          This name is in the ComponentName flattened format (package/class)  -->
diff --git a/packages/SystemUI/src/com/android/systemui/statusbar/notification/row/NotificationContentView.java b/packages/SystemUI/src/com/android/systemui/statusbar/notification/row/NotificationContentView.java
index bf30cf9..c161da3 100644
--- a/packages/SystemUI/src/com/android/systemui/statusbar/notification/row/NotificationContentView.java
+++ b/packages/SystemUI/src/com/android/systemui/statusbar/notification/row/NotificationContentView.java
@@ -1489,7 +1489,7 @@
                 }
             }
         }
-        if (mHeadsUpChild != null) {
+        if (mHeadsUpChild != null && mSmartReplyConstants.getShowInHeadsUp()) {
             mHeadsUpSmartReplyView =
                     applySmartReplyView(mHeadsUpChild, smartRepliesAndActions, entry);
         }
diff --git a/packages/SystemUI/src/com/android/systemui/statusbar/policy/SmartReplyConstants.java b/packages/SystemUI/src/com/android/systemui/statusbar/policy/SmartReplyConstants.java
index 0c63e29..3bd0d45 100644
--- a/packages/SystemUI/src/com/android/systemui/statusbar/policy/SmartReplyConstants.java
+++ b/packages/SystemUI/src/com/android/systemui/statusbar/policy/SmartReplyConstants.java
@@ -45,16 +45,19 @@
             "max_squeeze_remeasure_attempts";
     private static final String KEY_EDIT_CHOICES_BEFORE_SENDING =
             "edit_choices_before_sending";
+    private static final String KEY_SHOW_IN_HEADS_UP = "show_in_heads_up";
 
     private final boolean mDefaultEnabled;
     private final boolean mDefaultRequiresP;
     private final int mDefaultMaxSqueezeRemeasureAttempts;
     private final boolean mDefaultEditChoicesBeforeSending;
+    private final boolean mDefaultShowInHeadsUp;
 
     private boolean mEnabled;
     private boolean mRequiresTargetingP;
     private int mMaxSqueezeRemeasureAttempts;
     private boolean mEditChoicesBeforeSending;
+    private boolean mShowInHeadsUp;
 
     private final Context mContext;
     private final KeyValueListParser mParser = new KeyValueListParser(',');
@@ -73,6 +76,8 @@
                 R.integer.config_smart_replies_in_notifications_max_squeeze_remeasure_attempts);
         mDefaultEditChoicesBeforeSending = resources.getBoolean(
                 R.bool.config_smart_replies_in_notifications_edit_choices_before_sending);
+        mDefaultShowInHeadsUp = resources.getBoolean(
+                R.bool.config_smart_replies_in_notifications_show_in_heads_up);
 
         mContext.getContentResolver().registerContentObserver(
                 Settings.Global.getUriFor(Settings.Global.SMART_REPLIES_IN_NOTIFICATIONS_FLAGS),
@@ -99,6 +104,7 @@
                     KEY_MAX_SQUEEZE_REMEASURE_ATTEMPTS, mDefaultMaxSqueezeRemeasureAttempts);
             mEditChoicesBeforeSending = mParser.getBoolean(
                     KEY_EDIT_CHOICES_BEFORE_SENDING, mDefaultEditChoicesBeforeSending);
+            mShowInHeadsUp = mParser.getBoolean(KEY_SHOW_IN_HEADS_UP, mDefaultShowInHeadsUp);
         }
     }
 
@@ -142,4 +148,11 @@
                 return mEditChoicesBeforeSending;
         }
     }
+
+    /**
+     * Returns whether smart suggestions should be enabled in heads-up notifications.
+     */
+    public boolean getShowInHeadsUp() {
+        return mShowInHeadsUp;
+    }
 }
diff --git a/packages/SystemUI/tests/src/com/android/systemui/statusbar/policy/SmartReplyConstantsTest.java b/packages/SystemUI/tests/src/com/android/systemui/statusbar/policy/SmartReplyConstantsTest.java
index 37a56a3..3cbf902 100644
--- a/packages/SystemUI/tests/src/com/android/systemui/statusbar/policy/SmartReplyConstantsTest.java
+++ b/packages/SystemUI/tests/src/com/android/systemui/statusbar/policy/SmartReplyConstantsTest.java
@@ -54,6 +54,7 @@
                 R.integer.config_smart_replies_in_notifications_max_squeeze_remeasure_attempts, 7);
         resources.addOverride(
                 R.bool.config_smart_replies_in_notifications_edit_choices_before_sending, false);
+        resources.addOverride(R.bool.config_smart_replies_in_notifications_show_in_heads_up, true);
         mConstants = new SmartReplyConstants(Handler.createAsync(Looper.myLooper()), mContext);
     }
 
@@ -152,6 +153,26 @@
                         RemoteInput.EDIT_CHOICES_BEFORE_SENDING_DISABLED));
     }
 
+    @Test
+    public void testShowInHeadsUpWithNoConfig() {
+        assertTrue(mConstants.isEnabled());
+        assertTrue(mConstants.getShowInHeadsUp());
+    }
+
+    @Test
+    public void testShowInHeadsUpEnabled() {
+        overrideSetting("enabled=true,show_in_heads_up=true");
+        triggerConstantsOnChange();
+        assertTrue(mConstants.getShowInHeadsUp());
+    }
+
+    @Test
+    public void testShowInHeadsUpDisabled() {
+        overrideSetting("enabled=true,show_in_heads_up=false");
+        triggerConstantsOnChange();
+        assertFalse(mConstants.getShowInHeadsUp());
+    }
+
     private void overrideSetting(String flags) {
         Settings.Global.putString(mContext.getContentResolver(),
                 Settings.Global.SMART_REPLIES_IN_NOTIFICATIONS_FLAGS, flags);
diff --git a/services/core/java/com/android/server/pm/LauncherAppsService.java b/services/core/java/com/android/server/pm/LauncherAppsService.java
index 7f1fb6c..aa9bc26 100644
--- a/services/core/java/com/android/server/pm/LauncherAppsService.java
+++ b/services/core/java/com/android/server/pm/LauncherAppsService.java
@@ -313,6 +313,10 @@
                     Settings.Global.SHOW_HIDDEN_LAUNCHER_ICON_APPS_ENABLED, 1) == 0) {
                 return launcherActivities;
             }
+            if (launcherActivities == null) {
+                // Cannot access profile, so we don't even return any hidden apps.
+                return null;
+            }
 
             final int callingUid = injectBinderCallingUid();
             final ArrayList<ResolveInfo> result = new ArrayList<>(launcherActivities.getList());
diff --git a/services/core/java/com/android/server/rollback/PackageRollbackData.java b/services/core/java/com/android/server/rollback/RollbackData.java
similarity index 65%
rename from services/core/java/com/android/server/rollback/PackageRollbackData.java
rename to services/core/java/com/android/server/rollback/RollbackData.java
index 15d1242..f0589aa 100644
--- a/services/core/java/com/android/server/rollback/PackageRollbackData.java
+++ b/services/core/java/com/android/server/rollback/RollbackData.java
@@ -20,17 +20,21 @@
 
 import java.io.File;
 import java.time.Instant;
+import java.util.ArrayList;
+import java.util.List;
 
 /**
- * Information about a rollback available for a particular package.
- * This is similar to {@link PackageRollbackInfo}, but extended with
- * additional information for internal bookkeeping.
+ * Information about a rollback available for a set of atomically installed
+ * packages.
  */
-class PackageRollbackData {
-    public final PackageRollbackInfo info;
+class RollbackData {
+    /**
+     * The per-package rollback information.
+     */
+    public final List<PackageRollbackInfo> packages = new ArrayList<>();
 
     /**
-     * The directory where the apk backup is stored.
+     * The directory where the rollback data is stored.
      */
     public final File backupDir;
 
@@ -38,12 +42,9 @@
      * The time when the upgrade occurred, for purposes of expiring
      * rollback data.
      */
-    public final Instant timestamp;
+    public Instant timestamp;
 
-    PackageRollbackData(PackageRollbackInfo info,
-            File backupDir, Instant timestamp) {
-        this.info = info;
+    RollbackData(File backupDir) {
         this.backupDir = backupDir;
-        this.timestamp = timestamp;
     }
 }
diff --git a/services/core/java/com/android/server/rollback/RollbackManagerServiceImpl.java b/services/core/java/com/android/server/rollback/RollbackManagerServiceImpl.java
index 0c21312..8021265 100644
--- a/services/core/java/com/android/server/rollback/RollbackManagerServiceImpl.java
+++ b/services/core/java/com/android/server/rollback/RollbackManagerServiceImpl.java
@@ -63,9 +63,11 @@
 import java.time.format.DateTimeParseException;
 import java.time.temporal.ChronoUnit;
 import java.util.ArrayList;
+import java.util.HashMap;
 import java.util.HashSet;
 import java.util.Iterator;
 import java.util.List;
+import java.util.Map;
 import java.util.Set;
 import java.util.concurrent.LinkedBlockingQueue;
 import java.util.concurrent.TimeUnit;
@@ -86,10 +88,20 @@
     // mLock is held when they are called.
     private final Object mLock = new Object();
 
+    // Package rollback data for rollback-enabled installs that have not yet
+    // been committed. Maps from sessionId to rollback data.
+    @GuardedBy("mLock")
+    private final Map<Integer, RollbackData> mPendingRollbacks = new HashMap<>();
+
+    // Map from child session id's for enabled rollbacks to their
+    // corresponding parent session ids.
+    @GuardedBy("mLock")
+    private final Map<Integer, Integer> mChildSessions = new HashMap<>();
+
     // Package rollback data available to be used for rolling back a package.
     // This list is null until the rollback data has been loaded.
     @GuardedBy("mLock")
-    private List<PackageRollbackData> mAvailableRollbacks;
+    private List<RollbackData> mAvailableRollbacks;
 
     // The list of recently executed rollbacks.
     // This list is null until the rollback data has been loaded.
@@ -102,14 +114,25 @@
     // to store this data:
     //   /data/rollback/
     //      available/
-    //          com.package.A-XXX/
-    //              base.apk
-    //              rollback.json
-    //          com.package.B-YYY/
-    //              base.apk
-    //              rollback.json
+    //          XXX/
+    //              com.package.A/
+    //                  base.apk
+    //                  info.json
+    //              enabled.txt
+    //          YYY/
+    //              com.package.B/
+    //                  base.apk
+    //                  info.json
+    //              enabled.txt
     //      recently_executed.json
-    // TODO: Use AtomicFile for rollback.json and recently_executed.json.
+    //
+    // * XXX, YYY are random strings from Files.createTempDirectory
+    // * info.json contains the package version to roll back from/to.
+    // * enabled.txt contains a timestamp for when the rollback was first
+    //   made available. This file is not written until the rollback is made
+    //   available.
+    //
+    // TODO: Use AtomicFile for all the .json files?
     private final File mRollbackDataDir;
     private final File mAvailableRollbacksDir;
     private final File mRecentlyExecutedRollbacksFile;
@@ -135,6 +158,9 @@
         // expiration.
         getHandler().post(() -> ensureRollbackDataLoaded());
 
+        PackageInstaller installer = mContext.getPackageManager().getPackageInstaller();
+        installer.registerSessionCallback(new SessionCallback(), getHandler());
+
         IntentFilter filter = new IntentFilter();
         filter.addAction(Intent.ACTION_PACKAGE_REPLACED);
         filter.addAction(Intent.ACTION_PACKAGE_FULLY_REMOVED);
@@ -199,27 +225,23 @@
                 android.Manifest.permission.MANAGE_ROLLBACKS,
                 "getAvailableRollback");
 
-        PackageRollbackInfo.PackageVersion installedVersion =
-                getInstalledPackageVersion(packageName);
-        if (installedVersion == null) {
+        RollbackData data = getRollbackForPackage(packageName);
+        if (data == null) {
             return null;
         }
 
-        synchronized (mLock) {
-            // TODO: Have ensureRollbackDataLoadedLocked return the list of
-            // available rollbacks, to hopefully avoid forgetting to call it?
-            ensureRollbackDataLoadedLocked();
-            for (int i = 0; i < mAvailableRollbacks.size(); ++i) {
-                PackageRollbackData data = mAvailableRollbacks.get(i);
-                if (data.info.packageName.equals(packageName)
-                        && data.info.higherVersion.equals(installedVersion)) {
-                    // TODO: For atomic installs, check all dependent packages
-                    // for available rollbacks and include that info here.
-                    return new RollbackInfo(data.info);
-                }
+        // Note: The rollback for the package ought to be for the currently
+        // installed version, otherwise the rollback data is out of date. In
+        // that rare case, we'll check when we execute the rollback whether
+        // it's out of date or not, so no need to check package versions here.
+
+        for (PackageRollbackInfo info : data.packages) {
+            if (info.packageName.equals(packageName)) {
+                // TODO: Once the RollbackInfo API supports info about
+                // dependant packages, add that info here.
+                return new RollbackInfo(info);
             }
         }
-
         return null;
     }
 
@@ -229,16 +251,14 @@
                 android.Manifest.permission.MANAGE_ROLLBACKS,
                 "getPackagesWithAvailableRollbacks");
 
-        // TODO: This may return packages whose rollback is out of date or
-        // expired.  Presumably that's okay because the package rollback could
-        // be expired anyway between when the caller calls this method and
-        // when the caller calls getAvailableRollback for more details.
         final Set<String> packageNames = new HashSet<>();
         synchronized (mLock) {
             ensureRollbackDataLoadedLocked();
             for (int i = 0; i < mAvailableRollbacks.size(); ++i) {
-                PackageRollbackData data = mAvailableRollbacks.get(i);
-                packageNames.add(data.info.packageName);
+                RollbackData data = mAvailableRollbacks.get(i);
+                for (PackageRollbackInfo info : data.packages) {
+                    packageNames.add(info.packageName);
+                }
             }
         }
         return new StringParceledListSlice(new ArrayList<>(packageNames));
@@ -279,47 +299,49 @@
      */
     private void executeRollbackInternal(RollbackInfo rollback,
             String callerPackageName, IntentSender statusReceiver) {
-        String packageName = rollback.targetPackage.packageName;
-        Log.i(TAG, "Initiating rollback of " + packageName);
+        String targetPackageName = rollback.targetPackage.packageName;
+        Log.i(TAG, "Initiating rollback of " + targetPackageName);
 
-        PackageRollbackInfo.PackageVersion installedVersion =
-                getInstalledPackageVersion(packageName);
-        if (installedVersion == null) {
-            // TODO: Test this case
-            sendFailure(statusReceiver, "Target package to roll back is not installed");
+        // Get the latest RollbackData for the target package.
+        RollbackData data = getRollbackForPackage(targetPackageName);
+        if (data == null) {
+            sendFailure(statusReceiver, "No rollback available for package.");
             return;
         }
 
-        if (!rollback.targetPackage.higherVersion.equals(installedVersion)) {
-            // TODO: Test this case
-            sendFailure(statusReceiver, "Target package version to roll back not installed.");
-            return;
+        // Verify the latest rollback matches the version requested.
+        // TODO: Check dependant packages too once RollbackInfo includes that
+        // information.
+        for (PackageRollbackInfo info : data.packages) {
+            if (info.packageName.equals(targetPackageName)
+                    && !rollback.targetPackage.higherVersion.equals(info.higherVersion)) {
+                sendFailure(statusReceiver, "Rollback is out of date.");
+                return;
+            }
         }
 
+        // Verify the RollbackData is up to date with what's installed on
+        // device.
         // TODO: We assume that between now and the time we commit the
         // downgrade install, the currently installed package version does not
         // change. This is not safe to assume, particularly in the case of a
         // rollback racing with a roll-forward fix of a buggy package.
         // Figure out how to ensure we don't commit the rollback if
         // roll forward happens at the same time.
-        PackageRollbackData data = null;
-        synchronized (mLock) {
-            ensureRollbackDataLoadedLocked();
-            for (int i = 0; i < mAvailableRollbacks.size(); ++i) {
-                PackageRollbackData available = mAvailableRollbacks.get(i);
-                // TODO: Check if available.info.lowerVersion matches
-                // rollback.targetPackage.lowerVersion?
-                if (available.info.packageName.equals(packageName)
-                        && available.info.higherVersion.equals(installedVersion)) {
-                    data = available;
-                    break;
-                }
+        for (PackageRollbackInfo info : data.packages) {
+            PackageRollbackInfo.PackageVersion installedVersion =
+                    getInstalledPackageVersion(info.packageName);
+            if (installedVersion == null) {
+                // TODO: Test this case
+                sendFailure(statusReceiver, "Package to roll back is not installed");
+                return;
             }
-        }
 
-        if (data == null) {
-            sendFailure(statusReceiver, "Rollback not available");
-            return;
+            if (!info.higherVersion.equals(installedVersion)) {
+                // TODO: Test this case
+                sendFailure(statusReceiver, "Package version to roll back not installed.");
+                return;
+            }
         }
 
         // Get a context for the caller to use to install the downgraded
@@ -334,29 +356,39 @@
 
         PackageManager pm = context.getPackageManager();
         try {
-            PackageInstaller.Session session = null;
-
             PackageInstaller packageInstaller = pm.getPackageInstaller();
-            PackageInstaller.SessionParams params = new PackageInstaller.SessionParams(
+            PackageInstaller.SessionParams parentParams = new PackageInstaller.SessionParams(
                     PackageInstaller.SessionParams.MODE_FULL_INSTALL);
-            params.setAllowDowngrade(true);
-            int sessionId = packageInstaller.createSession(params);
-            session = packageInstaller.openSession(sessionId);
+            parentParams.setAllowDowngrade(true);
+            parentParams.setMultiPackage();
+            int parentSessionId = packageInstaller.createSession(parentParams);
+            PackageInstaller.Session parentSession = packageInstaller.openSession(parentSessionId);
 
-            // TODO: Will it always be called "base.apk"? What about splits?
-            File baseApk = new File(data.backupDir, "base.apk");
-            try (ParcelFileDescriptor fd = ParcelFileDescriptor.open(baseApk,
-                    ParcelFileDescriptor.MODE_READ_ONLY)) {
-                final long token = Binder.clearCallingIdentity();
-                try {
-                    session.write("base.apk", 0, baseApk.length(), fd);
-                } finally {
-                    Binder.restoreCallingIdentity(token);
+            for (PackageRollbackInfo info : data.packages) {
+                PackageInstaller.SessionParams params = new PackageInstaller.SessionParams(
+                        PackageInstaller.SessionParams.MODE_FULL_INSTALL);
+                params.setAllowDowngrade(true);
+                int sessionId = packageInstaller.createSession(params);
+                PackageInstaller.Session session = packageInstaller.openSession(sessionId);
+
+                // TODO: Will it always be called "base.apk"? What about splits?
+                // What about apex?
+                File packageDir = new File(data.backupDir, info.packageName);
+                File baseApk = new File(packageDir, "base.apk");
+                try (ParcelFileDescriptor fd = ParcelFileDescriptor.open(baseApk,
+                        ParcelFileDescriptor.MODE_READ_ONLY)) {
+                    final long token = Binder.clearCallingIdentity();
+                    try {
+                        session.write("base.apk", 0, baseApk.length(), fd);
+                    } finally {
+                        Binder.restoreCallingIdentity(token);
+                    }
                 }
+                parentSession.addChildSessionId(sessionId);
             }
 
             final LocalIntentReceiver receiver = new LocalIntentReceiver();
-            session.commit(receiver.getIntentSender());
+            parentSession.commit(receiver.getIntentSender());
 
             Intent result = receiver.getResult();
             int status = result.getIntExtra(PackageInstaller.EXTRA_STATUS,
@@ -371,13 +403,14 @@
             sendSuccess(statusReceiver);
 
             Intent broadcast = new Intent(Intent.ACTION_PACKAGE_ROLLBACK_EXECUTED,
-                    Uri.fromParts("package", packageName, Manifest.permission.MANAGE_ROLLBACKS));
+                    Uri.fromParts("package", targetPackageName,
+                        Manifest.permission.MANAGE_ROLLBACKS));
 
             // TODO: This call emits the warning "Calling a method in the
             // system process without a qualified user". Fix that.
             mContext.sendBroadcast(broadcast);
         } catch (IOException e) {
-            Log.e(TAG, "Unable to roll back " + packageName, e);
+            Log.e(TAG, "Unable to roll back " + targetPackageName, e);
             sendFailure(statusReceiver, "IOException: " + e.toString());
             return;
         }
@@ -408,12 +441,15 @@
         // testing anyway.
         synchronized (mLock) {
             ensureRollbackDataLoadedLocked();
-            Iterator<PackageRollbackData> iter = mAvailableRollbacks.iterator();
+            Iterator<RollbackData> iter = mAvailableRollbacks.iterator();
             while (iter.hasNext()) {
-                PackageRollbackData data = iter.next();
-                if (data.info.packageName.equals(packageName)) {
-                    iter.remove();
-                    removeFile(data.backupDir);
+                RollbackData data = iter.next();
+                for (PackageRollbackInfo info : data.packages) {
+                    if (info.packageName.equals(packageName)) {
+                        iter.remove();
+                        removeFile(data.backupDir);
+                        break;
+                    }
                 }
             }
         }
@@ -453,27 +489,41 @@
         mAvailableRollbacksDir.mkdirs();
         mAvailableRollbacks = new ArrayList<>();
         for (File rollbackDir : mAvailableRollbacksDir.listFiles()) {
-            if (rollbackDir.isDirectory()) {
-                // TODO: How to detect and clean up an invalid rollback
-                // directory? We don't know if it's invalid because something
-                // went wrong, or if it's only temporarily invalid because
-                // it's in the process of being created.
+            File enabledFile = new File(rollbackDir, "enabled.txt");
+            // TODO: Delete any directories without an enabled.txt? That could
+            // potentially delete pending rollback data if reloadPersistedData
+            // is called, though there's no reason besides testing for that to
+            // be called.
+            if (rollbackDir.isDirectory() && enabledFile.isFile()) {
+                RollbackData data = new RollbackData(rollbackDir);
                 try {
-                    File jsonFile = new File(rollbackDir, "rollback.json");
-                    String jsonString = IoUtils.readFileAsString(jsonFile.getAbsolutePath());
-                    JSONObject jsonObject = new JSONObject(jsonString);
-                    String packageName = jsonObject.getString("packageName");
-                    long higherVersionCode = jsonObject.getLong("higherVersionCode");
-                    long lowerVersionCode = jsonObject.getLong("lowerVersionCode");
-                    Instant timestamp = Instant.parse(jsonObject.getString("timestamp"));
-                    PackageRollbackData data = new PackageRollbackData(
-                            new PackageRollbackInfo(packageName,
-                                new PackageRollbackInfo.PackageVersion(higherVersionCode),
-                                new PackageRollbackInfo.PackageVersion(lowerVersionCode)),
-                            rollbackDir, timestamp);
+                    PackageRollbackInfo info = null;
+                    for (File packageDir : rollbackDir.listFiles()) {
+                        if (packageDir.isDirectory()) {
+                            File jsonFile = new File(packageDir, "info.json");
+                            String jsonString = IoUtils.readFileAsString(
+                                    jsonFile.getAbsolutePath());
+                            JSONObject jsonObject = new JSONObject(jsonString);
+                            String packageName = jsonObject.getString("packageName");
+                            long higherVersionCode = jsonObject.getLong("higherVersionCode");
+                            long lowerVersionCode = jsonObject.getLong("lowerVersionCode");
+
+                            data.packages.add(new PackageRollbackInfo(packageName,
+                                        new PackageRollbackInfo.PackageVersion(higherVersionCode),
+                                        new PackageRollbackInfo.PackageVersion(lowerVersionCode)));
+                        }
+                    }
+
+                    if (data.packages.isEmpty()) {
+                        throw new IOException("No package rollback info found");
+                    }
+
+                    String enabledString = IoUtils.readFileAsString(enabledFile.getAbsolutePath());
+                    data.timestamp = Instant.parse(enabledString.trim());
                     mAvailableRollbacks.add(data);
                 } catch (IOException | JSONException | DateTimeParseException e) {
                     Log.e(TAG, "Unable to read rollback data at " + rollbackDir, e);
+                    removeFile(rollbackDir);
                 }
             }
         }
@@ -521,13 +571,16 @@
 
         synchronized (mLock) {
             ensureRollbackDataLoadedLocked();
-            Iterator<PackageRollbackData> iter = mAvailableRollbacks.iterator();
+            Iterator<RollbackData> iter = mAvailableRollbacks.iterator();
             while (iter.hasNext()) {
-                PackageRollbackData data = iter.next();
-                if (data.info.packageName.equals(packageName)
-                        && !data.info.higherVersion.equals(installedVersion)) {
-                    iter.remove();
-                    removeFile(data.backupDir);
+                RollbackData data = iter.next();
+                for (PackageRollbackInfo info : data.packages) {
+                    if (info.packageName.equals(packageName)
+                            && !info.higherVersion.equals(installedVersion)) {
+                        iter.remove();
+                        removeFile(data.backupDir);
+                        break;
+                    }
                 }
             }
         }
@@ -643,9 +696,9 @@
         synchronized (mLock) {
             ensureRollbackDataLoadedLocked();
 
-            Iterator<PackageRollbackData> iter = mAvailableRollbacks.iterator();
+            Iterator<RollbackData> iter = mAvailableRollbacks.iterator();
             while (iter.hasNext()) {
-                PackageRollbackData data = iter.next();
+                RollbackData data = iter.next();
                 if (!now.isBefore(data.timestamp.plusMillis(ROLLBACK_LIFETIME_DURATION_MILLIS))) {
                     iter.remove();
                     removeFile(data.backupDir);
@@ -673,6 +726,23 @@
         return mHandlerThread.getThreadHandler();
     }
 
+    // Returns true if <code>session</code> has installFlags and code path
+    // matching the installFlags and new package code path given to
+    // enableRollback.
+    private boolean sessionMatchesForEnableRollback(PackageInstaller.SessionInfo session,
+            int installFlags, File newPackageCodePath) {
+        if (session == null || session.resolvedBaseCodePath == null) {
+            return false;
+        }
+
+        File packageCodePath = new File(session.resolvedBaseCodePath).getParentFile();
+        if (newPackageCodePath.equals(packageCodePath) && installFlags == session.installFlags) {
+            return true;
+        }
+
+        return false;
+    }
+
     /**
      * Called via broadcast by the package manager when a package is being
      * staged for install with rollback enabled. Called before the package has
@@ -705,6 +775,34 @@
         String packageName = newPackage.packageName;
         Log.i(TAG, "Enabling rollback for install of " + packageName);
 
+        // Figure out the session id associated with this install.
+        int parentSessionId = PackageInstaller.SessionInfo.INVALID_ID;
+        int childSessionId = PackageInstaller.SessionInfo.INVALID_ID;
+        PackageInstaller installer = mContext.getPackageManager().getPackageInstaller();
+        for (PackageInstaller.SessionInfo info : installer.getAllSessions()) {
+            if (info.isMultiPackage()) {
+                for (int childId : info.getChildSessionIds()) {
+                    PackageInstaller.SessionInfo child = installer.getSessionInfo(childId);
+                    if (sessionMatchesForEnableRollback(child, installFlags, newPackageCodePath)) {
+                        // TODO: Check we only have one matching session?
+                        parentSessionId = info.getSessionId();
+                        childSessionId = childId;
+                    }
+                }
+            } else {
+                if (sessionMatchesForEnableRollback(info, installFlags, newPackageCodePath)) {
+                    // TODO: Check we only have one matching session?
+                    parentSessionId = info.getSessionId();
+                    childSessionId = parentSessionId;
+                }
+            }
+        }
+
+        if (parentSessionId == PackageInstaller.SessionInfo.INVALID_ID) {
+            Log.e(TAG, "Unable to find session id for enabled rollback.");
+            return false;
+        }
+
         PackageRollbackInfo.PackageVersion newVersion =
                 new PackageRollbackInfo.PackageVersion(newPackage.versionCode);
 
@@ -720,52 +818,53 @@
         PackageRollbackInfo.PackageVersion installedVersion =
                 new PackageRollbackInfo.PackageVersion(installedPackage.getLongVersionCode());
 
-        File backupDir;
+        PackageRollbackInfo info = new PackageRollbackInfo(
+                packageName, newVersion, installedVersion);
+
+        RollbackData data;
         try {
-            backupDir = Files.createTempDirectory(
-                mAvailableRollbacksDir.toPath(), packageName + "-").toFile();
+            synchronized (mLock) {
+                mChildSessions.put(childSessionId, parentSessionId);
+                data = mPendingRollbacks.get(parentSessionId);
+                if (data == null) {
+                    File backupDir = Files.createTempDirectory(
+                            mAvailableRollbacksDir.toPath(), null).toFile();
+                    data = new RollbackData(backupDir);
+                    mPendingRollbacks.put(parentSessionId, data);
+                }
+                data.packages.add(info);
+            }
         } catch (IOException e) {
             Log.e(TAG, "Unable to create rollback for " + packageName, e);
             return false;
         }
 
-        // TODO: Should the timestamp be for when we commit the install, not
-        // when we create the pending one?
-        Instant timestamp = Instant.now();
+        File packageDir = new File(data.backupDir, packageName);
+        packageDir.mkdirs();
         try {
             JSONObject json = new JSONObject();
             json.put("packageName", packageName);
             json.put("higherVersionCode", newVersion.versionCode);
             json.put("lowerVersionCode", installedVersion.versionCode);
-            json.put("timestamp", timestamp.toString());
 
-            File jsonFile = new File(backupDir, "rollback.json");
+            File jsonFile = new File(packageDir, "info.json");
             PrintWriter pw = new PrintWriter(jsonFile);
             pw.println(json.toString());
             pw.close();
         } catch (IOException | JSONException e) {
             Log.e(TAG, "Unable to create rollback for " + packageName, e);
-            removeFile(backupDir);
+            removeFile(packageDir);
             return false;
         }
 
         // TODO: Copy by hard link instead to save on cpu and storage space?
-        int status = PackageManagerServiceUtils.copyPackage(installedPackage.codePath, backupDir);
+        int status = PackageManagerServiceUtils.copyPackage(installedPackage.codePath, packageDir);
         if (status != PackageManager.INSTALL_SUCCEEDED) {
             Log.e(TAG, "Unable to copy package for rollback for " + packageName);
-            removeFile(backupDir);
+            removeFile(packageDir);
             return false;
         }
 
-        PackageRollbackData data = new PackageRollbackData(
-                new PackageRollbackInfo(packageName, newVersion, installedVersion),
-                backupDir, timestamp);
-
-        synchronized (mLock) {
-            ensureRollbackDataLoadedLocked();
-            mAvailableRollbacks.add(data);
-        }
-
         return true;
     }
 
@@ -829,4 +928,87 @@
 
         return new PackageRollbackInfo.PackageVersion(pkgInfo.getLongVersionCode());
     }
+
+    private class SessionCallback extends PackageInstaller.SessionCallback {
+
+        @Override
+        public void onCreated(int sessionId) { }
+
+        @Override
+        public void onBadgingChanged(int sessionId) { }
+
+        @Override
+        public void onActiveChanged(int sessionId, boolean active) { }
+
+        @Override
+        public void onProgressChanged(int sessionId, float progress) { }
+
+        @Override
+        public void onFinished(int sessionId, boolean success) {
+            RollbackData data = null;
+            synchronized (mLock) {
+                Integer parentSessionId = mChildSessions.remove(sessionId);
+                if (parentSessionId != null) {
+                    sessionId = parentSessionId;
+                }
+                data = mPendingRollbacks.remove(sessionId);
+            }
+
+            if (data != null) {
+                if (success) {
+                    try {
+                        data.timestamp = Instant.now();
+                        File enabledFile = new File(data.backupDir, "enabled.txt");
+                        PrintWriter pw = new PrintWriter(enabledFile);
+                        pw.println(data.timestamp.toString());
+                        pw.close();
+
+                        synchronized (mLock) {
+                            // Note: There is a small window of time between when
+                            // the session has been committed by the package
+                            // manager and when we make the rollback available
+                            // here. Presumably the window is small enough that
+                            // nobody will want to roll back the newly installed
+                            // package before we make the rollback available.
+                            // TODO: We'll lose the rollback data if the
+                            // device reboots between when the session is
+                            // committed and this point. Revisit this after
+                            // adding support for rollback of staged installs.
+                            ensureRollbackDataLoadedLocked();
+                            mAvailableRollbacks.add(data);
+                        }
+                    } catch (IOException e) {
+                        Log.e(TAG, "Unable to enable rollback", e);
+                        removeFile(data.backupDir);
+                    }
+                } else {
+                    // The install session was aborted, clean up the pending
+                    // install.
+                    removeFile(data.backupDir);
+                }
+            }
+        }
+    }
+
+    /*
+     * Returns the RollbackData, if any, for an available rollback that would
+     * roll back the given package. Note: This assumes we have at most one
+     * available rollback for a given package at any one time.
+     */
+    private RollbackData getRollbackForPackage(String packageName) {
+        synchronized (mLock) {
+            // TODO: Have ensureRollbackDataLoadedLocked return the list of
+            // available rollbacks, to hopefully avoid forgetting to call it?
+            ensureRollbackDataLoadedLocked();
+            for (int i = 0; i < mAvailableRollbacks.size(); ++i) {
+                RollbackData data = mAvailableRollbacks.get(i);
+                for (PackageRollbackInfo info : data.packages) {
+                    if (info.packageName.equals(packageName)) {
+                        return data;
+                    }
+                }
+            }
+        }
+        return null;
+    }
 }
diff --git a/tests/RollbackTest/src/com/android/tests/rollback/RollbackTest.java b/tests/RollbackTest/src/com/android/tests/rollback/RollbackTest.java
index 0ccfb19..77cd9d8 100644
--- a/tests/RollbackTest/src/com/android/tests/rollback/RollbackTest.java
+++ b/tests/RollbackTest/src/com/android/tests/rollback/RollbackTest.java
@@ -108,6 +108,10 @@
             }
 
             // The app should not be available for rollback.
+            // TODO: See if there is a way to remove this race condition
+            // between when the app is uninstalled and when the previously
+            // available rollback, if any, is removed.
+            Thread.sleep(1000);
             assertNull(rm.getAvailableRollback(TEST_APP_A));
             assertFalse(rm.getPackagesWithAvailableRollbacks().contains(TEST_APP_A));
 
@@ -125,6 +129,10 @@
             assertEquals(2, RollbackTestUtils.getInstalledVersion(TEST_APP_A));
 
             // The app should now be available for rollback.
+            // TODO: See if there is a way to remove this race condition
+            // between when the app is installed and when the rollback
+            // is made available.
+            Thread.sleep(1000);
             assertTrue(rm.getPackagesWithAvailableRollbacks().contains(TEST_APP_A));
             RollbackInfo rollback = rm.getAvailableRollback(TEST_APP_A);
             assertNotNull(rollback);
@@ -182,6 +190,8 @@
 
             RollbackManager rm = RollbackTestUtils.getRollbackManager();
 
+            // TODO: Test this with multi-package rollback, not just single
+            // package rollback.
             // Prep installation of TEST_APP_A
             RollbackTestUtils.uninstall(TEST_APP_A);
             RollbackTestUtils.install("RollbackTestAppAv1.apk", false);
@@ -189,6 +199,10 @@
             assertEquals(2, RollbackTestUtils.getInstalledVersion(TEST_APP_A));
 
             // The app should now be available for rollback.
+            // TODO: See if there is a way to remove this race condition
+            // between when the app is installed and when the rollback
+            // is made available.
+            Thread.sleep(1000);
             assertTrue(rm.getPackagesWithAvailableRollbacks().contains(TEST_APP_A));
             RollbackInfo rollback = rm.getAvailableRollback(TEST_APP_A);
             assertNotNull(rollback);
@@ -263,6 +277,10 @@
             assertEquals(2, RollbackTestUtils.getInstalledVersion(TEST_APP_A));
 
             // The app should now be available for rollback.
+            // TODO: See if there is a way to remove this race condition
+            // between when the app is installed and when the rollback
+            // is made available.
+            Thread.sleep(1000);
             assertTrue(rm.getPackagesWithAvailableRollbacks().contains(TEST_APP_A));
             RollbackInfo rollback = rm.getAvailableRollback(TEST_APP_A);
             assertNotNull(rollback);
@@ -405,6 +423,10 @@
 
             // Both test apps should now be available for rollback, and the
             // targetPackage returned for rollback should be correct.
+            // TODO: See if there is a way to remove this race condition
+            // between when the app is installed and when the rollback
+            // is made available.
+            Thread.sleep(1000);
             RollbackInfo rollbackA = rm.getAvailableRollback(TEST_APP_A);
             assertNotNull(rollbackA);
             assertEquals(TEST_APP_A, rollbackA.targetPackage.packageName);
@@ -491,7 +513,7 @@
      * TODO: Stop ignoring this test once support for multi-package rollback
      * is implemented.
      */
-    @Ignore @Test
+    @Test
     public void testMultiPackage() throws Exception {
         try {
             RollbackTestUtils.adoptShellPermissionIdentity(