String[] getPluginDirectories() {
ArrayList<String> directories = new ArrayList<String>();
PackageManager pm = this.mAppContext.getPackageManager();
List<ResolveInfo> plugins =
pm.queryIntentServices(
new Intent(PLUGIN_ACTION), PackageManager.GET_SERVICES | PackageManager.GET_META_DATA);
synchronized (mPackageInfoCache) {
// clear the list of existing packageInfo objects
mPackageInfoCache.clear();
for (ResolveInfo info : plugins) {
// retrieve the plugin's service information
ServiceInfo serviceInfo = info.serviceInfo;
if (serviceInfo == null) {
Log.w(LOGTAG, "Ignore bad plugin");
continue;
}
Log.w(LOGTAG, "Loading plugin: " + serviceInfo.packageName);
// retrieve information from the plugin's manifest
PackageInfo pkgInfo;
try {
pkgInfo =
pm.getPackageInfo(
serviceInfo.packageName,
PackageManager.GET_PERMISSIONS | PackageManager.GET_SIGNATURES);
} catch (Exception e) {
Log.w(LOGTAG, "Can't find plugin: " + serviceInfo.packageName);
continue;
}
if (pkgInfo == null) {
Log.w(
LOGTAG,
"Loading plugin: "
+ serviceInfo.packageName
+ ". Could not load package information.");
continue;
}
/*
* find the location of the plugin's shared library. The default
* is to assume the app is either a user installed app or an
* updated system app. In both of these cases the library is
* stored in the app's data directory.
*/
String directory = pkgInfo.applicationInfo.dataDir + "/lib";
final int appFlags = pkgInfo.applicationInfo.flags;
final int updatedSystemFlags =
ApplicationInfo.FLAG_SYSTEM | ApplicationInfo.FLAG_UPDATED_SYSTEM_APP;
// preloaded system app with no user updates
if ((appFlags & updatedSystemFlags) == ApplicationInfo.FLAG_SYSTEM) {
directory = PLUGIN_SYSTEM_LIB + pkgInfo.packageName;
}
// check if the plugin has the required permissions
String permissions[] = pkgInfo.requestedPermissions;
if (permissions == null) {
Log.w(
LOGTAG,
"Loading plugin: "
+ serviceInfo.packageName
+ ". Does not have required permission.");
continue;
}
boolean permissionOk = false;
for (String permit : permissions) {
if (PLUGIN_PERMISSION.equals(permit)) {
permissionOk = true;
break;
}
}
if (!permissionOk) {
Log.w(
LOGTAG,
"Loading plugin: "
+ serviceInfo.packageName
+ ". Does not have required permission (2).");
continue;
}
// check to ensure the plugin is properly signed
Signature signatures[] = pkgInfo.signatures;
if (signatures == null) {
Log.w(LOGTAG, "Loading plugin: " + serviceInfo.packageName + ". Not signed.");
continue;
}
// determine the type of plugin from the manifest
if (serviceInfo.metaData == null) {
Log.e(LOGTAG, "The plugin '" + serviceInfo.name + "' has no type defined");
continue;
}
String pluginType = serviceInfo.metaData.getString(PLUGIN_TYPE);
if (!TYPE_NATIVE.equals(pluginType)) {
Log.e(LOGTAG, "Unrecognized plugin type: " + pluginType);
continue;
}
try {
Class<?> cls = getPluginClass(serviceInfo.packageName, serviceInfo.name);
// TODO implement any requirements of the plugin class here!
boolean classFound = true;
if (!classFound) {
Log.e(
LOGTAG,
"The plugin's class' "
+ serviceInfo.name
+ "' does not extend the appropriate class.");
continue;
}
} catch (NameNotFoundException e) {
Log.e(LOGTAG, "Can't find plugin: " + serviceInfo.packageName);
continue;
} catch (ClassNotFoundException e) {
Log.e(LOGTAG, "Can't find plugin's class: " + serviceInfo.name);
continue;
}
// if all checks have passed then make the plugin available
mPackageInfoCache.add(pkgInfo);
directories.add(directory);
}
}
return directories.toArray(new String[directories.size()]);
}
/*
* Non-recursive version of object descend. This consumes more memory than recursive in-depth
* traversal but prevents stack overflows on long chains of objects
* or complex graphs (a max. recursion depth on my machine was ~5000 objects linked in a chain
* so not too much).
*/
private static long measureObjectSize(Object root) {
// Objects seen so far.
final IdentityHashSet<Object> seen = new IdentityHashSet<Object>();
// Class cache with reference Field and precalculated shallow size.
final IdentityHashMap<Class<?>, ClassCache> classCache =
new IdentityHashMap<Class<?>, ClassCache>();
// Stack of objects pending traversal. Recursion caused stack overflows.
final ArrayList<Object> stack = new ArrayList<Object>();
stack.add(root);
long totalSize = 0;
while (!stack.isEmpty()) {
final Object ob = stack.remove(stack.size() - 1);
if (ob == null || seen.contains(ob)) {
continue;
}
seen.add(ob);
final Class<?> obClazz = ob.getClass();
if (obClazz.isArray()) {
/*
* Consider an array, possibly of primitive types. Push any of its references to
* the processing stack and accumulate this array's shallow size.
*/
long size = NUM_BYTES_ARRAY_HEADER;
final int len = Array.getLength(ob);
if (len > 0) {
Class<?> componentClazz = obClazz.getComponentType();
if (componentClazz.isPrimitive()) {
size += (long) len * primitiveSizes.get(componentClazz);
} else {
size += (long) NUM_BYTES_OBJECT_REF * len;
// Push refs for traversal later.
for (int i = len; --i >= 0; ) {
final Object o = Array.get(ob, i);
if (o != null && !seen.contains(o)) {
stack.add(o);
}
}
}
}
totalSize += alignObjectSize(size);
} else {
/*
* Consider an object. Push any references it has to the processing stack
* and accumulate this object's shallow size.
*/
try {
ClassCache cachedInfo = classCache.get(obClazz);
if (cachedInfo == null) {
classCache.put(obClazz, cachedInfo = createCacheEntry(obClazz));
}
for (Field f : cachedInfo.referenceFields) {
// Fast path to eliminate redundancies.
final Object o = f.get(ob);
if (o != null && !seen.contains(o)) {
stack.add(o);
}
}
totalSize += cachedInfo.alignedShallowInstanceSize;
} catch (IllegalAccessException e) {
// this should never happen as we enabled setAccessible().
throw new RuntimeException("Reflective field access failed?", e);
}
}
}
// Help the GC (?).
seen.clear();
stack.clear();
classCache.clear();
return totalSize;
}