/*
* Copyright (C) 2012 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.input;
import com.android.internal.util.ArrayUtils;
import com.android.internal.util.FastXmlSerializer;
import com.android.internal.util.XmlUtils;
import org.xmlpull.v1.XmlPullParser;
import org.xmlpull.v1.XmlPullParserException;
import org.xmlpull.v1.XmlSerializer;
import android.util.AtomicFile;
import android.util.Slog;
import android.util.Xml;
import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.util.ArrayList;
import java.util.Collections;
import java.util.HashMap;
import java.util.Map;
import java.util.Set;
import libcore.io.IoUtils;
import libcore.util.Objects;
/**
* Manages persistent state recorded by the input manager service as an XML file.
* Caller must acquire lock on the data store before accessing it.
*
* File format:
* <code>
* <input-mananger-state>
* <input-devices>
* <input-device descriptor="xxxxx" keyboard-layout="yyyyy" />
* >input-devices>
* >/input-manager-state>
* </code>
*/
final class PersistentDataStore {
static final String TAG = "InputManager";
// Input device state by descriptor.
private final HashMap<String, InputDeviceState> mInputDevices =
new HashMap<String, InputDeviceState>();
private final AtomicFile mAtomicFile;
// True if the data has been loaded.
private boolean mLoaded;
// True if there are changes to be saved.
private boolean mDirty;
public PersistentDataStore() {
mAtomicFile = new AtomicFile(new File("/data/system/input-manager-state.xml"));
}
public void saveIfNeeded() {
if (mDirty) {
save();
mDirty = false;
}
}
public String getCurrentKeyboardLayout(String inputDeviceDescriptor) {
InputDeviceState state = getInputDeviceState(inputDeviceDescriptor, false);
return state != null ? state.getCurrentKeyboardLayout() : null;
}
public boolean setCurrentKeyboardLayout(String inputDeviceDescriptor,
String keyboardLayoutDescriptor) {
InputDeviceState state = getInputDeviceState(inputDeviceDescriptor, true);
if (state.setCurrentKeyboardLayout(keyboardLayoutDescriptor)) {
setDirty();
return true;
}
return false;
}
public String[] getKeyboardLayouts(String inputDeviceDescriptor) {
InputDeviceState state = getInputDeviceState(inputDeviceDescriptor, false);
if (state == null) {
return (String[])ArrayUtils.emptyArray(String.class);
}
return state.getKeyboardLayouts();
}
public boolean addKeyboardLayout(String inputDeviceDescriptor,
String keyboardLayoutDescriptor) {
InputDeviceState state = getInputDeviceState(inputDeviceDescriptor, true);
if (state.addKeyboardLayout(keyboardLayoutDescriptor)) {
setDirty();
return true;
}
return false;
}
public boolean removeKeyboardLayout(String inputDeviceDescriptor,
String keyboardLayoutDescriptor) {
InputDeviceState state = getInputDeviceState(inputDeviceDescriptor, true);
if (state.removeKeyboardLayout(keyboardLayoutDescriptor)) {
setDirty();
return true;
}
return false;
}
public boolean switchKeyboardLayout(String inputDeviceDescriptor, int direction) {
InputDeviceState state = getInputDeviceState(inputDeviceDescriptor, false);
if (state != null && state.switchKeyboardLayout(direction)) {
setDirty();
return true;
}
return false;
}
public boolean removeUninstalledKeyboardLayouts(Set<String> availableKeyboardLayouts) {
boolean changed = false;
for (InputDeviceState state : mInputDevices.values()) {
if (state.removeUninstalledKeyboardLayouts(availableKeyboardLayouts)) {
changed = true;
}
}
if (changed) {
setDirty();
return true;
}
return false;
}
private InputDeviceState getInputDeviceState(String inputDeviceDescriptor,
boolean createIfAbsent) {
loadIfNeeded();
InputDeviceState state = mInputDevices.get(inputDeviceDescriptor);
if (state == null && createIfAbsent) {
state = new InputDeviceState();
mInputDevices.put(inputDeviceDescriptor, state);
setDirty();
}
return state;
}
private void loadIfNeeded() {
if (!mLoaded) {
load();
mLoaded = true;
}
}
private void setDirty() {
mDirty = true;
}
private void clearState() {
mInputDevices.clear();
}
private void load() {
clearState();
final InputStream is;
try {
is = mAtomicFile.openRead();
} catch (FileNotFoundException ex) {
return;
}
XmlPullParser parser;
try {
parser = Xml.newPullParser();
parser.setInput(new BufferedInputStream(is), null);
loadFromXml(parser);
} catch (IOException ex) {
Slog.w(InputManagerService.TAG, "Failed to load input manager persistent store data.", ex);
clearState();
} catch (XmlPullParserException ex) {
Slog.w(InputManagerService.TAG, "Failed to load input manager persistent store data.", ex);
clearState();
} finally {
IoUtils.closeQuietly(is);
}
}
private void save() {
final FileOutputStream os;
try {
os = mAtomicFile.startWrite();
boolean success = false;
try {
XmlSerializer serializer = new FastXmlSerializer();
serializer.setOutput(new BufferedOutputStream(os), "utf-8");
saveToXml(serializer);
serializer.flush();
success = true;
} finally {
if (success) {
mAtomicFile.finishWrite(os);
} else {
mAtomicFile.failWrite(os);
}
}
} catch (IOException ex) {
Slog.w(InputManagerService.TAG, "Failed to save input manager persistent store data.", ex);
}
}
private void loadFromXml(XmlPullParser parser)
throws IOException, XmlPullParserException {
XmlUtils.beginDocument(parser, "input-manager-state");
final int outerDepth = parser.getDepth();
while (XmlUtils.nextElementWithin(parser, outerDepth)) {
if (parser.getName().equals("input-devices")) {
loadInputDevicesFromXml(parser);
}
}
}
private void loadInputDevicesFromXml(XmlPullParser parser)
throws IOException, XmlPullParserException {
final int outerDepth = parser.getDepth();
while (XmlUtils.nextElementWithin(parser, outerDepth)) {
if (parser.getName().equals("input-device")) {
String descriptor = parser.getAttributeValue(null, "descriptor");
if (descriptor == null) {
throw new XmlPullParserException(
"Missing descriptor attribute on input-device.");
}
if (mInputDevices.containsKey(descriptor)) {
throw new XmlPullParserException("Found duplicate input device.");
}
InputDeviceState state = new InputDeviceState();
state.loadFromXml(parser);
mInputDevices.put(descriptor, state);
}
}
}
private void saveToXml(XmlSerializer serializer) throws IOException {
serializer.startDocument(null, true);
serializer.setFeature("http://xmlpull.org/v1/doc/features.html#indent-output", true);
serializer.startTag(null, "input-manager-state");
serializer.startTag(null, "input-devices");
for (Map.Entry<String, InputDeviceState> entry : mInputDevices.entrySet()) {
final String descriptor = entry.getKey();
final InputDeviceState state = entry.getValue();
serializer.startTag(null, "input-device");
serializer.attribute(null, "descriptor", descriptor);
state.saveToXml(serializer);
serializer.endTag(null, "input-device");
}
serializer.endTag(null, "input-devices");
serializer.endTag(null, "input-manager-state");
serializer.endDocument();
}
private static final class InputDeviceState {
private String mCurrentKeyboardLayout;
private ArrayList<String> mKeyboardLayouts = new ArrayList<String>();
public String getCurrentKeyboardLayout() {
return mCurrentKeyboardLayout;
}
public boolean setCurrentKeyboardLayout(String keyboardLayout) {
if (Objects.equal(mCurrentKeyboardLayout, keyboardLayout)) {
return false;
}
addKeyboardLayout(keyboardLayout);
mCurrentKeyboardLayout = keyboardLayout;
return true;
}
public String[] getKeyboardLayouts() {
if (mKeyboardLayouts.isEmpty()) {
return (String[])ArrayUtils.emptyArray(String.class);
}
return mKeyboardLayouts.toArray(new String[mKeyboardLayouts.size()]);
}
public boolean addKeyboardLayout(String keyboardLayout) {
int index = Collections.binarySearch(mKeyboardLayouts, keyboardLayout);
if (index >= 0) {
return false;
}
mKeyboardLayouts.add(-index - 1, keyboardLayout);
if (mCurrentKeyboardLayout == null) {
mCurrentKeyboardLayout = keyboardLayout;
}
return true;
}
public boolean removeKeyboardLayout(String keyboardLayout) {
int index = Collections.binarySearch(mKeyboardLayouts, keyboardLayout);
if (index < 0) {
return false;
}
mKeyboardLayouts.remove(index);
updateCurrentKeyboardLayoutIfRemoved(keyboardLayout, index);
return true;
}
private void updateCurrentKeyboardLayoutIfRemoved(
String removedKeyboardLayout, int removedIndex) {
if (Objects.equal(mCurrentKeyboardLayout, removedKeyboardLayout)) {
if (!mKeyboardLayouts.isEmpty()) {
int index = removedIndex;
if (index == mKeyboardLayouts.size()) {
index = 0;
}
mCurrentKeyboardLayout = mKeyboardLayouts.get(index);
} else {
mCurrentKeyboardLayout = null;
}
}
}
public boolean switchKeyboardLayout(int direction) {
final int size = mKeyboardLayouts.size();
if (size < 2) {
return false;
}
int index = Collections.binarySearch(mKeyboardLayouts, mCurrentKeyboardLayout);
assert index >= 0;
if (direction > 0) {
index = (index + 1) % size;
} else {
index = (index + size - 1) % size;
}
mCurrentKeyboardLayout = mKeyboardLayouts.get(index);
return true;
}
public boolean removeUninstalledKeyboardLayouts(Set<String> availableKeyboardLayouts) {
boolean changed = false;
for (int i = mKeyboardLayouts.size(); i-- > 0; ) {
String keyboardLayout = mKeyboardLayouts.get(i);
if (!availableKeyboardLayouts.contains(keyboardLayout)) {
Slog.i(TAG, "Removing uninstalled keyboard layout " + keyboardLayout);
mKeyboardLayouts.remove(i);
updateCurrentKeyboardLayoutIfRemoved(keyboardLayout, i);
changed = true;
}
}
return changed;
}
public void loadFromXml(XmlPullParser parser)
throws IOException, XmlPullParserException {
final int outerDepth = parser.getDepth();
while (XmlUtils.nextElementWithin(parser, outerDepth)) {
if (parser.getName().equals("keyboard-layout")) {
String descriptor = parser.getAttributeValue(null, "descriptor");
if (descriptor == null) {
throw new XmlPullParserException(
"Missing descriptor attribute on keyboard-layout.");
}
String current = parser.getAttributeValue(null, "current");
if (mKeyboardLayouts.contains(descriptor)) {
throw new XmlPullParserException(
"Found duplicate keyboard layout.");
}
mKeyboardLayouts.add(descriptor);
if (current != null && current.equals("true")) {
if (mCurrentKeyboardLayout != null) {
throw new XmlPullParserException(
"Found multiple current keyboard layouts.");
}
mCurrentKeyboardLayout = descriptor;
}
}
}
// Maintain invariant that layouts are sorted.
Collections.sort(mKeyboardLayouts);
// Maintain invariant that there is always a current keyboard layout unless
// there are none installed.
if (mCurrentKeyboardLayout == null && !mKeyboardLayouts.isEmpty()) {
mCurrentKeyboardLayout = mKeyboardLayouts.get(0);
}
}
public void saveToXml(XmlSerializer serializer) throws IOException {
for (String layout : mKeyboardLayouts) {
serializer.startTag(null, "keyboard-layout");
serializer.attribute(null, "descriptor", layout);
if (layout.equals(mCurrentKeyboardLayout)) {
serializer.attribute(null, "current", "true");
}
serializer.endTag(null, "keyboard-layout");
}
}
}
}