/*
* Copyright (C) 2006 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 android.app;
import android.annotation.UnsupportedAppUsage;
import android.content.pm.SharedLibraryInfo;
import android.os.Build;
import android.os.GraphicsEnvironment;
import android.os.Trace;
import android.util.ArrayMap;
import android.util.Log;
import com.android.internal.os.ClassLoaderFactory;
import dalvik.system.PathClassLoader;
import java.util.ArrayList;
import java.util.Collection;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
/** @hide */
public class ApplicationLoaders {
private static final String TAG = "ApplicationLoaders";
@UnsupportedAppUsage
public static ApplicationLoaders getDefault() {
return gApplicationLoaders;
}
ClassLoader getClassLoader(String zip, int targetSdkVersion, boolean isBundled,
String librarySearchPath, String libraryPermittedPath,
ClassLoader parent, String classLoaderName) {
return getClassLoaderWithSharedLibraries(zip, targetSdkVersion, isBundled,
librarySearchPath, libraryPermittedPath, parent, classLoaderName,
null);
}
ClassLoader getClassLoaderWithSharedLibraries(
String zip, int targetSdkVersion, boolean isBundled,
String librarySearchPath, String libraryPermittedPath,
ClassLoader parent, String classLoaderName,
List<ClassLoader> sharedLibraries) {
// For normal usage the cache key used is the same as the zip path.
return getClassLoader(zip, targetSdkVersion, isBundled, librarySearchPath,
libraryPermittedPath, parent, zip, classLoaderName, sharedLibraries);
}
/**
* Gets a class loader for a shared library. Additional dependent shared libraries are allowed
* to be specified (sharedLibraries).
*
* Additionally, as an optimization, this will return a pre-created ClassLoader if one has
* been cached by createAndCacheNonBootclasspathSystemClassLoaders.
*/
ClassLoader getSharedLibraryClassLoaderWithSharedLibraries(String zip, int targetSdkVersion,
boolean isBundled, String librarySearchPath, String libraryPermittedPath,
ClassLoader parent, String classLoaderName, List<ClassLoader> sharedLibraries) {
ClassLoader loader = getCachedNonBootclasspathSystemLib(zip, parent, classLoaderName,
sharedLibraries);
if (loader != null) {
return loader;
}
return getClassLoaderWithSharedLibraries(zip, targetSdkVersion, isBundled,
librarySearchPath, libraryPermittedPath, parent, classLoaderName, sharedLibraries);
}
private ClassLoader getClassLoader(String zip, int targetSdkVersion, boolean isBundled,
String librarySearchPath, String libraryPermittedPath,
ClassLoader parent, String cacheKey,
String classLoaderName, List<ClassLoader> sharedLibraries) {
/*
* This is the parent we use if they pass "null" in. In theory
* this should be the "system" class loader; in practice we
* don't use that and can happily (and more efficiently) use the
* bootstrap class loader.
*/
ClassLoader baseParent = ClassLoader.getSystemClassLoader().getParent();
synchronized (mLoaders) {
if (parent == null) {
parent = baseParent;
}
/*
* If we're one step up from the base class loader, find
* something in our cache. Otherwise, we create a whole
* new ClassLoader for the zip archive.
*/
if (parent == baseParent) {
ClassLoader loader = mLoaders.get(cacheKey);
if (loader != null) {
return loader;
}
Trace.traceBegin(Trace.TRACE_TAG_ACTIVITY_MANAGER, zip);
ClassLoader classloader = ClassLoaderFactory.createClassLoader(
zip, librarySearchPath, libraryPermittedPath, parent,
targetSdkVersion, isBundled, classLoaderName, sharedLibraries);
Trace.traceEnd(Trace.TRACE_TAG_ACTIVITY_MANAGER);
Trace.traceBegin(Trace.TRACE_TAG_ACTIVITY_MANAGER, "setLayerPaths");
GraphicsEnvironment.getInstance().setLayerPaths(
classloader, librarySearchPath, libraryPermittedPath);
Trace.traceEnd(Trace.TRACE_TAG_ACTIVITY_MANAGER);
if (cacheKey != null) {
mLoaders.put(cacheKey, classloader);
}
return classloader;
}
Trace.traceBegin(Trace.TRACE_TAG_ACTIVITY_MANAGER, zip);
ClassLoader loader = ClassLoaderFactory.createClassLoader(
zip, null, parent, classLoaderName, sharedLibraries);
Trace.traceEnd(Trace.TRACE_TAG_ACTIVITY_MANAGER);
return loader;
}
}
/**
* Caches system library class loaders which are not on the bootclasspath but are still used
* by many system apps.
*
* All libraries in the closure of libraries to be loaded must be in libs. A library can
* only depend on libraries that come before it in the list.
*/
public void createAndCacheNonBootclasspathSystemClassLoaders(SharedLibraryInfo[] libs) {
if (mSystemLibsCacheMap != null) {
throw new IllegalStateException("Already cached.");
}
mSystemLibsCacheMap = new HashMap<String, CachedClassLoader>();
for (SharedLibraryInfo lib : libs) {
createAndCacheNonBootclasspathSystemClassLoader(lib);
}
}
/**
* Caches a single non-bootclasspath class loader.
*
* All of this library's dependencies must have previously been cached. Otherwise, an exception
* is thrown.
*/
private void createAndCacheNonBootclasspathSystemClassLoader(SharedLibraryInfo lib) {
String path = lib.getPath();
List<SharedLibraryInfo> dependencies = lib.getDependencies();
// get cached classloaders for dependencies
ArrayList<ClassLoader> sharedLibraries = null;
if (dependencies != null) {
sharedLibraries = new ArrayList<ClassLoader>(dependencies.size());
for (SharedLibraryInfo dependency : dependencies) {
String dependencyPath = dependency.getPath();
CachedClassLoader cached = mSystemLibsCacheMap.get(dependencyPath);
if (cached == null) {
throw new IllegalStateException("Failed to find dependency " + dependencyPath
+ " of cachedlibrary " + path);
}
sharedLibraries.add(cached.loader);
}
}
// assume cached libraries work with current sdk since they are built-in
ClassLoader classLoader = getClassLoader(path, Build.VERSION.SDK_INT, true /*isBundled*/,
null /*librarySearchPath*/, null /*libraryPermittedPath*/, null /*parent*/,
null /*cacheKey*/, null /*classLoaderName*/, sharedLibraries /*sharedLibraries*/);
if (classLoader == null) {
// bad configuration or break in classloading code
throw new IllegalStateException("Failed to cache " + path);
}
CachedClassLoader cached = new CachedClassLoader();
cached.loader = classLoader;
cached.sharedLibraries = sharedLibraries;
Log.d(TAG, "Created zygote-cached class loader: " + path);
mSystemLibsCacheMap.put(path, cached);
}
private static boolean sharedLibrariesEquals(List<ClassLoader> lhs, List<ClassLoader> rhs) {
if (lhs == null) {
return rhs == null;
}
return lhs.equals(rhs);
}
/**
* Returns lib cached with createAndCacheNonBootclasspathSystemClassLoader. This is called by
* the zygote during caching.
*
* If there is an error or the cache is not available, this returns null.
*/
public ClassLoader getCachedNonBootclasspathSystemLib(String zip, ClassLoader parent,
String classLoaderName, List<ClassLoader> sharedLibraries) {
if (mSystemLibsCacheMap == null) {
return null;
}
// we only cache top-level libs with the default class loader
if (parent != null || classLoaderName != null) {
return null;
}
CachedClassLoader cached = mSystemLibsCacheMap.get(zip);
if (cached == null) {
return null;
}
// cached must be built and loaded in the same environment
if (!sharedLibrariesEquals(sharedLibraries, cached.sharedLibraries)) {
Log.w(TAG, "Unexpected environment for cached library: (" + sharedLibraries + "|"
+ cached.sharedLibraries + ")");
return null;
}
Log.d(TAG, "Returning zygote-cached class loader: " + zip);
return cached.loader;
}
/**
* Creates a classloader for the WebView APK and places it in the cache of loaders maintained
* by this class. This is used in the WebView zygote, where its presence in the cache speeds up
* startup and enables memory sharing.
*/
public ClassLoader createAndCacheWebViewClassLoader(String packagePath, String libsPath,
String cacheKey) {
// The correct paths are calculated by WebViewZygote in the system server and passed to
// us here. We hardcode the other parameters: WebView always targets the current SDK,
// does not need to use non-public system libraries, and uses the base classloader as its
// parent to permit usage of the cache.
// The cache key is passed separately to enable the stub WebView to be cached under the
// stub's APK path, when the actual package path is the donor APK.
return getClassLoader(packagePath, Build.VERSION.SDK_INT, false, libsPath, null, null,
cacheKey, null /* classLoaderName */, null /* sharedLibraries */);
}
/**
* Adds a new path the classpath of the given loader.
* @throws IllegalStateException if the provided class loader is not a {@link PathClassLoader}.
*/
void addPath(ClassLoader classLoader, String dexPath) {
if (!(classLoader instanceof PathClassLoader)) {
throw new IllegalStateException("class loader is not a PathClassLoader");
}
final PathClassLoader baseDexClassLoader = (PathClassLoader) classLoader;
baseDexClassLoader.addDexPath(dexPath);
}
/**
* @hide
*/
void addNative(ClassLoader classLoader, Collection<String> libPaths) {
if (!(classLoader instanceof PathClassLoader)) {
throw new IllegalStateException("class loader is not a PathClassLoader");
}
final PathClassLoader baseDexClassLoader = (PathClassLoader) classLoader;
baseDexClassLoader.addNativePath(libPaths);
}
@UnsupportedAppUsage
private final ArrayMap<String, ClassLoader> mLoaders = new ArrayMap<>();
private static final ApplicationLoaders gApplicationLoaders = new ApplicationLoaders();
private static class CachedClassLoader {
ClassLoader loader;
/**
* The shared libraries used when constructing loader for verification.
*/
List<ClassLoader> sharedLibraries;
}
/**
* This is a map of zip to associated class loader.
*/
private Map<String, CachedClassLoader> mSystemLibsCacheMap = null;
}