Add API to get hibernating packages

Add API to AppHibernationService to get hibernating packages so
Settings can access this information.

Bug: 175829330
Test: atest AppHibernationServiceTest
Change-Id: Icd186807c19ece55a21fc4d240d2f0132951af82
diff --git a/core/api/system-current.txt b/core/api/system-current.txt
index f9ff3f2..5ce5075 100644
--- a/core/api/system-current.txt
+++ b/core/api/system-current.txt
@@ -1422,6 +1422,7 @@
 package android.apphibernation {
 
   public final class AppHibernationManager {
+    method @NonNull @RequiresPermission(android.Manifest.permission.MANAGE_APP_HIBERNATION) public java.util.List<java.lang.String> getHibernatingPackagesForUser();
     method @RequiresPermission(android.Manifest.permission.MANAGE_APP_HIBERNATION) public boolean isHibernatingForUser(@NonNull String);
     method @RequiresPermission(android.Manifest.permission.MANAGE_APP_HIBERNATION) public boolean isHibernatingGlobally(@NonNull String);
     method @RequiresPermission(android.Manifest.permission.MANAGE_APP_HIBERNATION) public void setHibernatingForUser(@NonNull String, boolean);
diff --git a/core/java/android/apphibernation/AppHibernationManager.java b/core/java/android/apphibernation/AppHibernationManager.java
index 132cc40..de77848 100644
--- a/core/java/android/apphibernation/AppHibernationManager.java
+++ b/core/java/android/apphibernation/AppHibernationManager.java
@@ -24,6 +24,8 @@
 import android.os.RemoteException;
 import android.os.ServiceManager;
 
+import java.util.List;
+
 /**
  * This class provides an API surface for system apps to manipulate the app hibernation
  * state of a package for the user provided in the context.
@@ -111,4 +113,20 @@
             throw e.rethrowFromSystemServer();
         }
     }
+
+    /**
+     * Get the hibernating packages for the user. This is equivalent to the list of packages for
+     * the user that return true for {@link #isHibernatingForUser}.
+     *
+     * @hide
+     */
+    @SystemApi
+    @RequiresPermission(value = android.Manifest.permission.MANAGE_APP_HIBERNATION)
+    public @NonNull List<String> getHibernatingPackagesForUser() {
+        try {
+            return mIAppHibernationService.getHibernatingPackagesForUser(mContext.getUserId());
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
 }
diff --git a/core/java/android/apphibernation/IAppHibernationService.aidl b/core/java/android/apphibernation/IAppHibernationService.aidl
index 6a068ee..afdb3fe 100644
--- a/core/java/android/apphibernation/IAppHibernationService.aidl
+++ b/core/java/android/apphibernation/IAppHibernationService.aidl
@@ -25,4 +25,5 @@
     void setHibernatingForUser(String packageName, int userId, boolean isHibernating);
     boolean isHibernatingGlobally(String packageName);
     void setHibernatingGlobally(String packageName, boolean isHibernating);
+    List<String> getHibernatingPackagesForUser(int userId);
 }
\ No newline at end of file
diff --git a/services/core/java/com/android/server/apphibernation/AppHibernationService.java b/services/core/java/com/android/server/apphibernation/AppHibernationService.java
index aa7da77..b3373d0 100644
--- a/services/core/java/com/android/server/apphibernation/AppHibernationService.java
+++ b/services/core/java/com/android/server/apphibernation/AppHibernationService.java
@@ -293,6 +293,35 @@
     }
 
     /**
+     * Get the hibernating packages for the given user. This is equivalent to the list of
+     * packages for the user that return true for {@link #isHibernatingForUser}.
+     */
+    @NonNull List<String> getHibernatingPackagesForUser(int userId) {
+        ArrayList<String> hibernatingPackages = new ArrayList<>();
+        if (!checkHibernationEnabled("getHibernatingPackagesForUser")) {
+            return hibernatingPackages;
+        }
+        getContext().enforceCallingOrSelfPermission(
+                android.Manifest.permission.MANAGE_APP_HIBERNATION,
+                "Caller does not have MANAGE_APP_HIBERNATION permission.");
+        userId = handleIncomingUser(userId, "getHibernatingPackagesForUser");
+        if (!mUserManager.isUserUnlockingOrUnlocked(userId)) {
+            Slog.w(TAG, "Attempt to get hibernating packages for a stopped or nonexistent user "
+                    + userId);
+            return hibernatingPackages;
+        }
+        synchronized (mLock) {
+            Map<String, UserLevelState> userStates = mUserStates.get(userId);
+            for (UserLevelState state : userStates.values()) {
+                if (state.hibernated) {
+                    hibernatingPackages.add(state.packageName);
+                }
+            }
+            return hibernatingPackages;
+        }
+    }
+
+    /**
      * Put an app into hibernation for a given user, allowing user-level optimizations to occur.
      *
      * @param pkgState package hibernation state
@@ -619,6 +648,11 @@
         }
 
         @Override
+        public List<String> getHibernatingPackagesForUser(int userId) {
+            return mService.getHibernatingPackagesForUser(userId);
+        }
+
+        @Override
         public void onShellCommand(@Nullable FileDescriptor in, @Nullable FileDescriptor out,
                 @Nullable FileDescriptor err, @NonNull String[] args,
                 @Nullable ShellCallback callback, @NonNull ResultReceiver resultReceiver) {
diff --git a/services/tests/servicestests/src/com/android/server/apphibernation/AppHibernationServiceTest.java b/services/tests/servicestests/src/com/android/server/apphibernation/AppHibernationServiceTest.java
index 1c96838..1b8ab21 100644
--- a/services/tests/servicestests/src/com/android/server/apphibernation/AppHibernationServiceTest.java
+++ b/services/tests/servicestests/src/com/android/server/apphibernation/AppHibernationServiceTest.java
@@ -18,6 +18,7 @@
 
 import static android.content.pm.PackageManager.MATCH_ANY_USER;
 
+import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertTrue;
 import static org.mockito.AdditionalAnswers.returnsArgAt;
 import static org.mockito.ArgumentMatchers.any;
@@ -67,6 +68,7 @@
     private static final String PACKAGE_SCHEME = "package";
     private static final String PACKAGE_NAME_1 = "package1";
     private static final String PACKAGE_NAME_2 = "package2";
+    private static final String PACKAGE_NAME_3 = "package3";
     private static final int USER_ID_1 = 1;
     private static final int USER_ID_2 = 2;
 
@@ -107,6 +109,8 @@
 
         List<PackageInfo> packages = new ArrayList<>();
         packages.add(makePackageInfo(PACKAGE_NAME_1));
+        packages.add(makePackageInfo(PACKAGE_NAME_2));
+        packages.add(makePackageInfo(PACKAGE_NAME_3));
         doReturn(new ParceledListSlice<>(packages)).when(mIPackageManager).getInstalledPackages(
                 intThat(arg -> (arg & MATCH_ANY_USER) != 0), anyInt());
         mAppHibernationService.onBootPhase(SystemService.PHASE_BOOT_COMPLETED);
@@ -179,6 +183,26 @@
         assertTrue(mAppHibernationService.isHibernatingGlobally(PACKAGE_NAME_1));
     }
 
+    @Test
+    public void testGetHibernatingPackagesForUser_returnsCorrectPackages() throws RemoteException {
+        // GIVEN an unlocked user with all packages installed
+        UserInfo userInfo =
+                addUser(USER_ID_2, new String[]{PACKAGE_NAME_1, PACKAGE_NAME_2, PACKAGE_NAME_3});
+        mAppHibernationService.onUserUnlocking(new SystemService.TargetUser(userInfo));
+        doReturn(true).when(mUserManager).isUserUnlockingOrUnlocked(USER_ID_2);
+
+        // WHEN packages are hibernated for the user
+        mAppHibernationService.setHibernatingForUser(PACKAGE_NAME_1, USER_ID_2, true);
+        mAppHibernationService.setHibernatingForUser(PACKAGE_NAME_2, USER_ID_2, true);
+
+        // THEN the hibernating packages returned matches
+        List<String> hibernatingPackages =
+                mAppHibernationService.getHibernatingPackagesForUser(USER_ID_2);
+        assertEquals(2, hibernatingPackages.size());
+        assertTrue(hibernatingPackages.contains(PACKAGE_NAME_1));
+        assertTrue(hibernatingPackages.contains(PACKAGE_NAME_2));
+    }
+
     /**
      * Add a mock user with one package.
      */