Gustav Sennton | 8b17926 | 2016-03-14 11:31:14 +0000 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2016 The Android Open Source Project |
| 3 | * |
| 4 | * Licensed under the Apache License, Version 2.0 (the "License"); |
| 5 | * you may not use this file except in compliance with the License. |
| 6 | * You may obtain a copy of the License at |
| 7 | * |
| 8 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 9 | * |
| 10 | * Unless required by applicable law or agreed to in writing, software |
| 11 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 13 | * See the License for the specific language governing permissions and |
| 14 | * limitations under the License. |
| 15 | */ |
| 16 | |
| 17 | package com.android.server.webkit; |
| 18 | |
| 19 | import android.app.ActivityManagerNative; |
| 20 | import android.app.AppGlobals; |
| 21 | import android.content.Context; |
| 22 | import android.content.pm.PackageInfo; |
| 23 | import android.content.res.XmlResourceParser; |
| 24 | import android.os.RemoteException; |
| 25 | import android.os.UserHandle; |
| 26 | import android.provider.Settings; |
| 27 | import android.util.AndroidRuntimeException; |
| 28 | import android.util.Log; |
| 29 | import android.webkit.WebViewFactory; |
| 30 | import android.webkit.WebViewFactory.MissingWebViewPackageException; |
| 31 | import android.webkit.WebViewProviderInfo; |
| 32 | |
| 33 | import com.android.internal.util.XmlUtils; |
| 34 | |
| 35 | import java.io.IOException; |
| 36 | import java.util.ArrayList; |
| 37 | import java.util.List; |
| 38 | |
| 39 | import org.xmlpull.v1.XmlPullParserException; |
| 40 | |
| 41 | /** |
| 42 | * Default implementation for the WebView preparation Utility interface. |
| 43 | * @hide |
| 44 | */ |
| 45 | public class WebViewUtilityImpl implements WebViewUtilityInterface { |
| 46 | private static final String TAG = WebViewUtilityImpl.class.getSimpleName(); |
| 47 | private static final String TAG_START = "webviewproviders"; |
| 48 | private static final String TAG_WEBVIEW_PROVIDER = "webviewprovider"; |
| 49 | private static final String TAG_PACKAGE_NAME = "packageName"; |
| 50 | private static final String TAG_DESCRIPTION = "description"; |
| 51 | // Whether or not the provider must be explicitly chosen by the user to be used. |
| 52 | private static final String TAG_AVAILABILITY = "availableByDefault"; |
| 53 | private static final String TAG_SIGNATURE = "signature"; |
| 54 | private static final String TAG_FALLBACK = "isFallback"; |
| 55 | |
| 56 | /** |
| 57 | * Returns all packages declared in the framework resources as potential WebView providers. |
| 58 | * @hide |
| 59 | * */ |
| 60 | @Override |
| 61 | public WebViewProviderInfo[] getWebViewPackages() { |
| 62 | int numFallbackPackages = 0; |
| 63 | XmlResourceParser parser = null; |
| 64 | List<WebViewProviderInfo> webViewProviders = new ArrayList<WebViewProviderInfo>(); |
| 65 | try { |
| 66 | parser = AppGlobals.getInitialApplication().getResources().getXml( |
| 67 | com.android.internal.R.xml.config_webview_packages); |
| 68 | XmlUtils.beginDocument(parser, TAG_START); |
| 69 | while(true) { |
| 70 | XmlUtils.nextElement(parser); |
| 71 | String element = parser.getName(); |
| 72 | if (element == null) { |
| 73 | break; |
| 74 | } |
| 75 | if (element.equals(TAG_WEBVIEW_PROVIDER)) { |
| 76 | String packageName = parser.getAttributeValue(null, TAG_PACKAGE_NAME); |
| 77 | if (packageName == null) { |
| 78 | throw new MissingWebViewPackageException( |
| 79 | "WebView provider in framework resources missing package name"); |
| 80 | } |
| 81 | String description = parser.getAttributeValue(null, TAG_DESCRIPTION); |
| 82 | if (description == null) { |
| 83 | throw new MissingWebViewPackageException( |
| 84 | "WebView provider in framework resources missing description"); |
| 85 | } |
| 86 | boolean availableByDefault = "true".equals( |
| 87 | parser.getAttributeValue(null, TAG_AVAILABILITY)); |
| 88 | boolean isFallback = "true".equals( |
| 89 | parser.getAttributeValue(null, TAG_FALLBACK)); |
| 90 | WebViewProviderInfo currentProvider = |
| 91 | new WebViewProviderInfo(packageName, description, availableByDefault, |
| 92 | isFallback, readSignatures(parser)); |
| 93 | if (currentProvider.isFallbackPackage()) { |
| 94 | numFallbackPackages++; |
| 95 | if (numFallbackPackages > 1) { |
| 96 | throw new AndroidRuntimeException( |
| 97 | "There can be at most one webview fallback package."); |
| 98 | } |
| 99 | } |
| 100 | webViewProviders.add(currentProvider); |
| 101 | } |
| 102 | else { |
| 103 | Log.e(TAG, "Found an element that is not a webview provider"); |
| 104 | } |
| 105 | } |
| 106 | } catch(XmlPullParserException e) { |
| 107 | throw new MissingWebViewPackageException("Error when parsing WebView meta data " + e); |
| 108 | } catch(IOException e) { |
| 109 | throw new MissingWebViewPackageException("Error when parsing WebView meta data " + e); |
| 110 | } finally { |
| 111 | if (parser != null) parser.close(); |
| 112 | } |
| 113 | return webViewProviders.toArray(new WebViewProviderInfo[webViewProviders.size()]); |
| 114 | } |
| 115 | |
| 116 | /** |
| 117 | * Reads all signatures at the current depth (within the current provider) from the XML parser. |
| 118 | */ |
| 119 | private static String[] readSignatures(XmlResourceParser parser) throws IOException, |
| 120 | XmlPullParserException { |
| 121 | List<String> signatures = new ArrayList<String>(); |
| 122 | int outerDepth = parser.getDepth(); |
| 123 | while(XmlUtils.nextElementWithin(parser, outerDepth)) { |
| 124 | if (parser.getName().equals(TAG_SIGNATURE)) { |
| 125 | // Parse the value within the signature tag |
| 126 | String signature = parser.nextText(); |
| 127 | signatures.add(signature); |
| 128 | } else { |
| 129 | Log.e(TAG, "Found an element in a webview provider that is not a signature"); |
| 130 | } |
| 131 | } |
| 132 | return signatures.toArray(new String[signatures.size()]); |
| 133 | } |
| 134 | |
| 135 | @Override |
| 136 | public int onWebViewProviderChanged(PackageInfo packageInfo) { |
| 137 | return WebViewFactory.onWebViewProviderChanged(packageInfo); |
| 138 | } |
| 139 | |
| 140 | @Override |
| 141 | public String getUserChosenWebViewProvider(Context context) { |
| 142 | return Settings.Global.getString(context.getContentResolver(), |
| 143 | Settings.Global.WEBVIEW_PROVIDER); |
| 144 | } |
| 145 | |
| 146 | @Override |
| 147 | public void updateUserSetting(Context context, String newProviderName) { |
| 148 | Settings.Global.putString(context.getContentResolver(), |
| 149 | Settings.Global.WEBVIEW_PROVIDER, |
| 150 | newProviderName == null ? "" : newProviderName); |
| 151 | } |
| 152 | |
| 153 | @Override |
| 154 | public void killPackageDependents(String packageName) { |
| 155 | try { |
| 156 | ActivityManagerNative.getDefault().killPackageDependents(packageName, |
| 157 | UserHandle.USER_ALL); |
| 158 | } catch (RemoteException e) { |
| 159 | } |
| 160 | } |
| 161 | } |