RollbackManagerService: Add getRollbackForPackage helper function. (035e974f) · Commits · e / os / android_frameworks_base

services/core/java/com/android/server/rollback/RollbackManagerServiceImpl.java

+49 −38

Original line number	Diff line number	Diff line
		@@ -220,27 +220,20 @@ class RollbackManagerServiceImpl extends IRollbackManager.Stub {
		android.Manifest.permission.MANAGE_ROLLBACKS,
		"getAvailableRollback");

		RollbackData data = getRollbackForPackage(packageName);
		if (data == null) {
		return null;
		}

		// 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		// installed version, otherwise the rollback data is out of date.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		// it's out of date or not, so no need to check package versions here.

		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);
		if (data.info.packageName.equals(packageName)) {
		// TODO: Once the RollbackInfo API supports info about
		// dependant packages, add that info here.
		// TODO: Once the RollbackInfo API supports info about dependant
		// packages, add that info here.
		return new RollbackInfo(data.info);
		}
		}
		}

		return null;
		}

		@Override
		public StringParceledListSlice getPackagesWithAvailableRollbacks() {
		@@ -297,43 +290,40 @@ class RollbackManagerServiceImpl extends IRollbackManager.Stub {
		String packageName = rollback.targetPackage.packageName;
		Log.i(TAG, "Initiating rollback of " + packageName);

		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(packageName);
		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.");
		// Verify the latest rollback matches the version requested.
		// TODO: Check dependant packages too once RollbackInfo includes that
		// information.
		if (!rollback.targetPackage.higherVersion.equals(data.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.
		RollbackData data = null;
		synchronized (mLock) {
		ensureRollbackDataLoadedLocked();
		for (int i = 0; i < mAvailableRollbacks.size(); ++i) {
		RollbackData 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;
		}
		}
		PackageRollbackInfo.PackageVersion installedVersion =
		getInstalledPackageVersion(data.info.packageName);
		if (installedVersion == null) {
		// TODO: Test this case
		sendFailure(statusReceiver, "Target package to roll back is not installed");
		return;
		}

		if (data == null) {
		sendFailure(statusReceiver, "Rollback not available");
		if (!data.info.higherVersion.equals(installedVersion)) {
		// TODO: Test this case
		sendFailure(statusReceiver, "Target package version to roll back not installed.");
		return;
		}

		@@ -359,6 +349,7 @@ class RollbackManagerServiceImpl extends IRollbackManager.Stub {
		session = packageInstaller.openSession(sessionId);

		// TODO: Will it always be called "base.apk"? What about splits?
		// What about apex?
		File packageDir = new File(data.backupDir, data.info.packageName);
		File baseApk = new File(packageDir, "base.apk");
		try (ParcelFileDescriptor fd = ParcelFileDescriptor.open(baseApk,
		@@ -947,4 +938,24 @@ class RollbackManagerServiceImpl extends IRollbackManager.Stub {
		}
		}
		}

		/*
		* 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);
		if (data.info.packageName.equals(packageName)) {
		return data;
		}
		}
		}
		return null;
		}
		}