Add fallback packages to be enabled iff no webview packages are valid
This patch makes it possible to declare a WebView package as a fallback
which means that the package will be enabled iff there exist no other
valid and enabled (and available-by-default) webview packages.
The enabled-state of a fallback package is updated at boot and if a
webview package is changed (it it's been up/downgraded or has had its
enabled-state changed).
This patch also adds 'webviewupdate' shell commands for enabling and
disabling this mechanism.
Bug: 26375524, 26375860
Change-Id: I151915e5d6d932697dab10aeb593687e6b9c817e
diff --git a/core/java/android/provider/Settings.java b/core/java/android/provider/Settings.java
index 0074788..5a92fc4 100755
--- a/core/java/android/provider/Settings.java
+++ b/core/java/android/provider/Settings.java
@@ -7033,6 +7033,14 @@
"webview_data_reduction_proxy_key";
/**
+ * Whether or not the WebView fallback mechanism should be enabled.
+ * 0=disabled, 1=enabled.
+ * @hide
+ */
+ public static final String WEBVIEW_FALLBACK_LOGIC_ENABLED =
+ "webview_fallback_logic_enabled";
+
+ /**
* Name of the package used as WebView provider (if unset the provider is instead determined
* by the system).
* @hide
diff --git a/core/java/android/webkit/IWebViewUpdateService.aidl b/core/java/android/webkit/IWebViewUpdateService.aidl
index 89d5d69..5697dfc 100644
--- a/core/java/android/webkit/IWebViewUpdateService.aidl
+++ b/core/java/android/webkit/IWebViewUpdateService.aidl
@@ -38,10 +38,14 @@
WebViewProviderResponse waitForAndGetProvider();
/**
- * DevelopmentSettings uses this to notify WebViewUpdateService that a
- * new provider has been selected by the user.
+ * DevelopmentSettings uses this to notify WebViewUpdateService that a new provider has been
+ * selected by the user. Returns the provider we end up switching to, this could be different to
+ * the one passed as argument to this method since the Dev Setting calling this method could be
+ * stale. I.e. the Dev setting could be letting the user choose uninstalled/disabled packages,
+ * it would then try to update the provider to such a package while in reality the update
+ * service would switch to another one.
*/
- void changeProviderAndSetting(String newProvider);
+ String changeProviderAndSetting(String newProvider);
/**
* DevelopmentSettings uses this to get the current available WebView
@@ -53,4 +57,15 @@
* Used by DevelopmentSetting to get the name of the WebView provider currently in use.
*/
String getCurrentWebViewPackageName();
+
+ /**
+ * Used by Settings to determine whether a certain package can be enabled/disabled by the user -
+ * the package should not be modifiable in this way if it is a fallback package.
+ */
+ boolean isFallbackPackage(String packageName);
+
+ /**
+ * Enable or disable the WebView package fallback mechanism.
+ */
+ void enableFallbackLogic(boolean enable);
}
diff --git a/core/java/android/webkit/WebViewFactory.java b/core/java/android/webkit/WebViewFactory.java
index b04b4c0..ad50ff6 100644
--- a/core/java/android/webkit/WebViewFactory.java
+++ b/core/java/android/webkit/WebViewFactory.java
@@ -21,6 +21,7 @@
import android.app.AppGlobals;
import android.app.Application;
import android.content.Context;
+import android.content.Intent;
import android.content.pm.ApplicationInfo;
import android.content.pm.PackageInfo;
import android.content.pm.PackageManager;
@@ -134,6 +135,7 @@
// Whether or not the provider must be explicitly chosen by the user to be used.
private static String TAG_AVAILABILITY = "availableByDefault";
private static String TAG_SIGNATURE = "signature";
+ private static String TAG_FALLBACK = "isFallback";
/**
* Reads all signatures at the current depth (within the current provider) from the XML parser.
@@ -159,6 +161,7 @@
* @hide
* */
public static WebViewProviderInfo[] getWebViewPackages() {
+ int numFallbackPackages = 0;
XmlResourceParser parser = null;
List<WebViewProviderInfo> webViewProviders = new ArrayList<WebViewProviderInfo>();
try {
@@ -182,13 +185,21 @@
throw new MissingWebViewPackageException(
"WebView provider in framework resources missing description");
}
- String availableByDefault = parser.getAttributeValue(null, TAG_AVAILABILITY);
- if (availableByDefault == null) {
- availableByDefault = "false";
- }
- webViewProviders.add(
+ boolean availableByDefault = "true".equals(
+ parser.getAttributeValue(null, TAG_AVAILABILITY));
+ boolean isFallback = "true".equals(
+ parser.getAttributeValue(null, TAG_FALLBACK));
+ WebViewProviderInfo currentProvider =
new WebViewProviderInfo(packageName, description, availableByDefault,
- readSignatures(parser)));
+ isFallback, readSignatures(parser));
+ if (currentProvider.isFallbackPackage()) {
+ numFallbackPackages++;
+ if (numFallbackPackages > 1) {
+ throw new AndroidRuntimeException(
+ "There can be at most one webview fallback package.");
+ }
+ }
+ webViewProviders.add(currentProvider);
}
else {
Log.e(LOGTAG, "Found an element that is not a webview provider");
@@ -641,6 +652,18 @@
return result;
}
+ /**
+ * Returns whether the entire package from an ACTION_PACKAGE_CHANGED intent was changed (rather
+ * than just one of its components).
+ * @hide
+ */
+ public static boolean entirePackageChanged(Intent intent) {
+ String[] componentList =
+ intent.getStringArrayExtra(Intent.EXTRA_CHANGED_COMPONENT_NAME_LIST);
+ return Arrays.asList(componentList).contains(
+ intent.getDataString().substring("package:".length()));
+ }
+
private static IWebViewUpdateService getUpdateService() {
return IWebViewUpdateService.Stub.asInterface(ServiceManager.getService("webviewupdate"));
}
diff --git a/core/java/android/webkit/WebViewProviderInfo.java b/core/java/android/webkit/WebViewProviderInfo.java
index 94e8b70..64c2caa 100644
--- a/core/java/android/webkit/WebViewProviderInfo.java
+++ b/core/java/android/webkit/WebViewProviderInfo.java
@@ -40,11 +40,12 @@
public WebViewPackageNotFoundException(Exception e) { super(e); }
}
- public WebViewProviderInfo(String packageName, String description, String availableByDefault,
- String[] signatures) {
+ public WebViewProviderInfo(String packageName, String description, boolean availableByDefault,
+ boolean isFallback, String[] signatures) {
this.packageName = packageName;
this.description = description;
- this.availableByDefault = availableByDefault.equals("true");
+ this.availableByDefault = availableByDefault;
+ this.isFallback = isFallback;
this.signatures = signatures;
}
@@ -114,6 +115,10 @@
return availableByDefault;
}
+ public boolean isFallbackPackage() {
+ return isFallback;
+ }
+
private void updatePackageInfo() {
try {
PackageManager pm = AppGlobals.getInitialApplication().getPackageManager();
@@ -165,6 +170,7 @@
public String packageName;
public String description;
private boolean availableByDefault;
+ private boolean isFallback;
private String[] signatures;