| /* |
| * Copyright (C) 2018 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License |
| */ |
| |
| package com.android.server.biometrics.face; |
| |
| import android.content.Context; |
| import android.hardware.face.Face; |
| import android.os.AsyncTask; |
| import android.os.Environment; |
| import android.util.AtomicFile; |
| import android.util.Slog; |
| import android.util.Xml; |
| |
| import com.android.internal.annotations.GuardedBy; |
| |
| import libcore.io.IoUtils; |
| import org.xmlpull.v1.XmlPullParser; |
| import org.xmlpull.v1.XmlPullParserException; |
| import org.xmlpull.v1.XmlSerializer; |
| |
| import java.io.File; |
| import java.io.FileInputStream; |
| import java.io.FileNotFoundException; |
| import java.io.FileOutputStream; |
| import java.io.IOException; |
| |
| |
| /** |
| * Class managing the set of faces per user across device reboots. |
| */ |
| class FaceUserState { |
| |
| private static final String TAG = "FaceState"; |
| private static final String FACE_FILE = "settings_face.xml"; |
| |
| private static final String TAG_FACE = "face"; |
| private static final String ATTR_DEVICE_ID = "deviceId"; |
| |
| private final File mFile; |
| |
| @GuardedBy("this") |
| private Face mFace = null; |
| private final Context mCtx; |
| |
| public FaceUserState(Context ctx, int userId) { |
| mFile = getFileForUser(userId); |
| mCtx = ctx; |
| synchronized (this) { |
| readStateSyncLocked(); |
| } |
| } |
| |
| public void addFace(int faceId) { |
| synchronized (this) { |
| mFace = new Face("Face", faceId, 0); |
| scheduleWriteStateLocked(); |
| } |
| } |
| |
| public void removeFace() { |
| synchronized (this) { |
| mFace = null; |
| scheduleWriteStateLocked(); |
| } |
| } |
| |
| public Face getFace() { |
| synchronized (this) { |
| return getCopy(mFace); |
| } |
| } |
| |
| private static File getFileForUser(int userId) { |
| return new File(Environment.getUserSystemDirectory(userId), FACE_FILE); |
| } |
| |
| private final Runnable mWriteStateRunnable = new Runnable() { |
| @Override |
| public void run() { |
| doWriteState(); |
| } |
| }; |
| |
| private void scheduleWriteStateLocked() { |
| AsyncTask.execute(mWriteStateRunnable); |
| } |
| |
| private Face getCopy(Face f) { |
| if (f == null) { |
| return null; |
| } |
| return new Face(f.getName(), f.getFaceId(), f.getDeviceId()); |
| } |
| |
| private void doWriteState() { |
| AtomicFile destination = new AtomicFile(mFile); |
| |
| Face face; |
| |
| synchronized (this) { |
| face = getCopy(mFace); |
| } |
| |
| FileOutputStream out = null; |
| try { |
| out = destination.startWrite(); |
| |
| XmlSerializer serializer = Xml.newSerializer(); |
| serializer.setOutput(out, "utf-8"); |
| serializer.setFeature("http://xmlpull.org/v1/doc/features.html#indent-output", true); |
| serializer.startDocument(null, true); |
| serializer.startTag(null, TAG_FACE); |
| if (face != null) { |
| serializer.attribute(null, ATTR_DEVICE_ID, Long.toString(face.getDeviceId())); |
| } |
| serializer.endTag(null, TAG_FACE); |
| serializer.endDocument(); |
| destination.finishWrite(out); |
| |
| // Any error while writing is fatal. |
| } catch (Throwable t) { |
| Slog.wtf(TAG, "Failed to write settings, restoring backup", t); |
| destination.failWrite(out); |
| throw new IllegalStateException("Failed to write face", t); |
| } finally { |
| IoUtils.closeQuietly(out); |
| } |
| } |
| |
| private void readStateSyncLocked() { |
| FileInputStream in; |
| if (!mFile.exists()) { |
| return; |
| } |
| try { |
| in = new FileInputStream(mFile); |
| } catch (FileNotFoundException fnfe) { |
| Slog.i(TAG, "No face state"); |
| return; |
| } |
| try { |
| XmlPullParser parser = Xml.newPullParser(); |
| parser.setInput(in, null); |
| parseStateLocked(parser); |
| |
| } catch (XmlPullParserException | IOException e) { |
| throw new IllegalStateException("Failed parsing settings file: " |
| + mFile , e); |
| } finally { |
| IoUtils.closeQuietly(in); |
| } |
| } |
| |
| private void parseStateLocked(XmlPullParser parser) |
| throws IOException, XmlPullParserException { |
| final int outerDepth = parser.getDepth(); |
| int type; |
| while ((type = parser.next()) != XmlPullParser.END_DOCUMENT |
| && (type != XmlPullParser.END_TAG || parser.getDepth() > outerDepth)) { |
| if (type == XmlPullParser.END_TAG || type == XmlPullParser.TEXT) { |
| continue; |
| } |
| |
| String tagName = parser.getName(); |
| if (tagName.equals(TAG_FACE)) { |
| parseFaceLocked(parser); |
| } |
| } |
| } |
| |
| private void parseFaceLocked(XmlPullParser parser) |
| throws IOException, XmlPullParserException { |
| String deviceId = parser.getAttributeValue(null, ATTR_DEVICE_ID); |
| |
| mFace = new Face("", 0, Integer.parseInt(deviceId)); |
| } |
| |
| } |