Use system setting for default geolocation permissions
This reverts change I0be5dbf4d99d07ca13b07fb299155c5aa17a51bd
and adds an observer on the new default geolocation permission
secure setting.
Bug http://b/issue?id=2535598
Change-Id: I4edcbd3080b7d3af5dc6d74f26779b6d92248010
diff --git a/src/com/android/browser/SystemAllowGeolocationOrigins.java b/src/com/android/browser/SystemAllowGeolocationOrigins.java
new file mode 100644
index 0000000..3f5a84e
--- /dev/null
+++ b/src/com/android/browser/SystemAllowGeolocationOrigins.java
@@ -0,0 +1,204 @@
+/*
+ * Copyright (C) 2010 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.browser;
+
+import android.content.Context;
+import android.content.SharedPreferences;
+import android.database.ContentObserver;
+import android.net.Uri;
+import android.os.AsyncTask;
+import android.os.Handler;
+import android.preference.PreferenceManager;
+import android.provider.Settings;
+import android.text.TextUtils;
+import android.webkit.GeolocationPermissions;
+import android.webkit.ValueCallback;
+
+import java.util.HashSet;
+import java.util.Set;
+
+/**
+ * Manages the interaction between the secure system setting for default geolocation
+ * permissions and the browser.
+ */
+class SystemAllowGeolocationOrigins {
+
+ // Preference key for the value of the system setting last read by the browser
+ private final static String LAST_READ_ALLOW_GEOLOCATION_ORIGINS =
+ "last_read_allow_geolocation_origins";
+
+ // The application context
+ private final Context mContext;
+
+ // The observer used to listen to the system setting.
+ private final SettingObserver mSettingObserver;
+
+ public SystemAllowGeolocationOrigins(Context context) {
+ mContext = context;
+ mSettingObserver = new SettingObserver();
+ }
+
+ /**
+ * Checks whether the setting has changed and installs an observer to listen for
+ * future changes. Must be called on the application main thread.
+ */
+ public void start() {
+ // Register to receive notifications when the system settings change.
+ Uri uri = Settings.Secure.getUriFor(Settings.Secure.ALLOWED_GEOLOCATION_ORIGINS);
+ mContext.getContentResolver().registerContentObserver(uri, false, mSettingObserver);
+
+ // Read and apply the setting if needed.
+ maybeApplySettingAsync();
+ }
+
+ /**
+ * Stops the manager.
+ */
+ public void stop() {
+ mContext.getContentResolver().unregisterContentObserver(mSettingObserver);
+ }
+
+ void maybeApplySettingAsync() {
+ new AsyncTask<Void,Void,Void>() {
+ @Override
+ protected Void doInBackground(Void... params) {
+ maybeApplySetting();
+ return null;
+ }
+ }.execute();
+ }
+
+ /**
+ * Checks to see if the system setting has changed and if so,
+ * updates the Geolocation permissions accordingly.
+ */
+ private void maybeApplySetting() {
+ // Get the new value
+ String newSetting = getSystemSetting();
+
+ // Get the last read value
+ SharedPreferences preferences = PreferenceManager.getDefaultSharedPreferences(mContext);
+ String lastReadSetting =
+ preferences.getString(LAST_READ_ALLOW_GEOLOCATION_ORIGINS, "");
+
+ // If the new value is the same as the last one we read, we're done.
+ if (TextUtils.equals(lastReadSetting, newSetting)) {
+ return;
+ }
+
+ // Save the new value as the last read value
+ preferences.edit()
+ .putString(LAST_READ_ALLOW_GEOLOCATION_ORIGINS, newSetting)
+ .commit();
+
+ Set<String> oldOrigins = parseAllowGeolocationOrigins(lastReadSetting);
+ Set<String> newOrigins = parseAllowGeolocationOrigins(newSetting);
+ Set<String> addedOrigins = setMinus(newOrigins, oldOrigins);
+ Set<String> removedOrigins = setMinus(oldOrigins, newOrigins);
+
+ // Remove the origins in the last read value
+ removeOrigins(removedOrigins);
+
+ // Add the origins in the new value
+ addOrigins(addedOrigins);
+ }
+
+ /**
+ * Parses the value of the default geolocation permissions setting.
+ *
+ * @param setting A space-separated list of origins.
+ * @return A mutable set of origins.
+ */
+ private static HashSet<String> parseAllowGeolocationOrigins(String setting) {
+ HashSet<String> origins = new HashSet<String>();
+ if (!TextUtils.isEmpty(setting)) {
+ for (String origin : setting.split("\\s+")) {
+ if (!TextUtils.isEmpty(origin)) {
+ origins.add(origin);
+ }
+ }
+ }
+ return origins;
+ }
+
+ /**
+ * Gets the difference between two sets. Does not modify any of the arguments.
+ *
+ * @return A set containing all elements in {@code x} that are not in {@code y}.
+ */
+ private <A> Set<A> setMinus(Set<A> x, Set<A> y) {
+ HashSet<A> z = new HashSet<A>(x.size());
+ for (A a : x) {
+ if (!y.contains(a)) {
+ z.add(a);
+ }
+ }
+ return z;
+ }
+
+ /**
+ * Gets the current system setting for default allowed geolocation origins.
+ *
+ * @return The default allowed origins. Returns {@code ""} if not set.
+ */
+ private String getSystemSetting() {
+ String value = Settings.Secure.getString(mContext.getContentResolver(),
+ Settings.Secure.ALLOWED_GEOLOCATION_ORIGINS);
+ return value == null ? "" : value;
+ }
+
+ /**
+ * Adds geolocation permissions for the given origins.
+ */
+ private void addOrigins(Set<String> origins) {
+ for (String origin : origins) {
+ GeolocationPermissions.getInstance().allow(origin);
+ }
+ }
+
+ /**
+ * Removes geolocation permissions for the given origins, if they are allowed.
+ * If they are denied or not set, nothing is done.
+ */
+ private void removeOrigins(Set<String> origins) {
+ for (final String origin : origins) {
+ GeolocationPermissions.getInstance().getAllowed(origin, new ValueCallback<Boolean>() {
+ public void onReceiveValue(Boolean value) {
+ if (value != null && value.booleanValue()) {
+ GeolocationPermissions.getInstance().clear(origin);
+ }
+ }
+ });
+ }
+ }
+
+ /**
+ * Listens for changes to the system setting.
+ */
+ private class SettingObserver extends ContentObserver {
+
+ SettingObserver() {
+ super(new Handler());
+ }
+
+ @Override
+ public void onChange(boolean selfChange) {
+ maybeApplySettingAsync();
+ }
+ }
+
+}