Add an api to get active staged session

This was requested during review of ag/6638240

Test: CtsStagedInstallHostTestCases
Bug: 127296534
Change-Id: Ifcc6270dc1655b1b07a0879c140f30967df8910d

api/current.txt

@@ -11384,6 +11384,7 @@ package android.content.pm {
   public class PackageInstaller {
     method public void abandonSession(int);
     method public int createSession(@NonNull android.content.pm.PackageInstaller.SessionParams) throws java.io.IOException;
+    method @Nullable public android.content.pm.PackageInstaller.SessionInfo getActiveStagedSession();
     method @NonNull public java.util.List<android.content.pm.PackageInstaller.SessionInfo> getAllSessions();
     method @NonNull public java.util.List<android.content.pm.PackageInstaller.SessionInfo> getMySessions();
     method @Nullable public android.content.pm.PackageInstaller.SessionInfo getSessionInfo(int);
@@ -11468,6 +11469,7 @@ package android.content.pm {
     method @NonNull public String getStagedSessionErrorMessage();
     method @NonNull public android.os.UserHandle getUser();
     method public boolean isActive();
+    method public boolean isCommitted();
     method public boolean isMultiPackage();
     method public boolean isSealed();
     method public boolean isStaged();

core/java/android/content/pm/PackageInstaller.java

@@ -496,6 +496,36 @@ public class PackageInstaller {
         }
     }
 
+    /**
+     * Returns an active staged session, or {@code null} if there is none.
+     *
+     * <p>Staged session is active iff:
+     * <ul>
+     *     <li>It is committed.
+     *     <li>It is not applied.
+     *     <li>It is not failed.
+     * </ul>
+     *
+     * <p>In case of a multi-apk session, parent session will be returned.
+     */
+    public @Nullable SessionInfo getActiveStagedSession() {
+        final List<SessionInfo> stagedSessions = getStagedSessions();
+        for (SessionInfo s : stagedSessions) {
+            if (s.isStagedSessionApplied() || s.isStagedSessionFailed()) {
+                // Finalized session.
+                continue;
+            }
+            if (s.getParentSessionId() != SessionInfo.INVALID_ID) {
+                // Child session.
+                continue;
+            }
+            if (s.isCommitted()) {
+                return s;
+            }
+        }
+        return null;
+    }
+
     /**
      * Uninstall the given package, removing it completely from the device. This
      * method is available to:
@@ -1769,6 +1799,9 @@ public class PackageInstaller {
         private int mStagedSessionErrorCode;
         private String mStagedSessionErrorMessage;
 
+        /** {@hide} */
+        public boolean isCommitted;
+
         /** {@hide} */
         @UnsupportedAppUsage
         public SessionInfo() {
@@ -1809,6 +1842,7 @@ public class PackageInstaller {
             isStagedSessionFailed = source.readBoolean();
             mStagedSessionErrorCode = source.readInt();
             mStagedSessionErrorMessage = source.readString();
+            isCommitted = source.readBoolean();
         }
 
         /**
@@ -2181,6 +2215,13 @@ public class PackageInstaller {
             mStagedSessionErrorMessage = errorMessage;
         }
 
+        /**
+         * Whenever this session was committed.
+         */
+        public boolean isCommitted() {
+            return isCommitted;
+        }
+
         @Override
         public int describeContents() {
             return 0;
@@ -2218,6 +2259,7 @@ public class PackageInstaller {
             dest.writeBoolean(isStagedSessionFailed);
             dest.writeInt(mStagedSessionErrorCode);
             dest.writeString(mStagedSessionErrorMessage);
+            dest.writeBoolean(isCommitted);
         }
 
         public static final Parcelable.Creator<SessionInfo>

services/core/java/com/android/server/pm/PackageInstallerSession.java

@@ -476,6 +476,7 @@ public class PackageInstallerSession extends IPackageInstallerSession.Stub {
                     mResolvedBaseFile.getAbsolutePath() : null;
             info.progress = mProgress;
             info.sealed = mSealed;
+            info.isCommitted = mCommitted;
             info.active = mActiveCount.get() > 0;
 
             info.mode = params.mode;