/*
* Copyright (C) 2013 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.documentsui;
import static com.android.documentsui.DocumentsActivity.TAG;
import android.content.ContentProviderClient;
import android.content.ContentResolver;
import android.content.Context;
import android.content.Intent;
import android.content.pm.ApplicationInfo;
import android.content.pm.PackageManager;
import android.content.pm.ProviderInfo;
import android.content.pm.ResolveInfo;
import android.database.ContentObserver;
import android.database.Cursor;
import android.net.Uri;
import android.os.AsyncTask;
import android.os.Handler;
import android.os.SystemClock;
import android.provider.DocumentsContract;
import android.provider.DocumentsContract.Root;
import android.util.Log;
import com.android.documentsui.BaseActivity.State;
import com.android.documentsui.model.RootInfo;
import com.android.internal.annotations.GuardedBy;
import com.android.internal.annotations.VisibleForTesting;
import com.google.android.collect.Lists;
import com.google.android.collect.Sets;
import com.google.common.collect.ArrayListMultimap;
import com.google.common.collect.Multimap;
import libcore.io.IoUtils;
import java.util.Collection;
import java.util.HashSet;
import java.util.List;
import java.util.Objects;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.TimeUnit;
/**
* Cache of known storage backends and their roots.
*/
public class RootsCache {
private static final boolean LOGD = false;
public static final Uri sNotificationUri = Uri.parse(
"content://com.android.documentsui.roots/");
private final Context mContext;
private final ContentObserver mObserver;
private final RootInfo mRecentsRoot = new RootInfo();
private final Object mLock = new Object();
private final CountDownLatch mFirstLoad = new CountDownLatch(1);
@GuardedBy("mLock")
private Multimap<String, RootInfo> mRoots = ArrayListMultimap.create();
@GuardedBy("mLock")
private HashSet<String> mStoppedAuthorities = Sets.newHashSet();
@GuardedBy("mObservedAuthorities")
private final HashSet<String> mObservedAuthorities = Sets.newHashSet();
public RootsCache(Context context) {
mContext = context;
mObserver = new RootsChangedObserver();
}
private class RootsChangedObserver extends ContentObserver {
public RootsChangedObserver() {
super(new Handler());
}
@Override
public void onChange(boolean selfChange, Uri uri) {
if (LOGD) Log.d(TAG, "Updating roots due to change at " + uri);
updateAuthorityAsync(uri.getAuthority());
}
}
/**
* Gather roots from all known storage providers.
*/
public void updateAsync() {
// Special root for recents
mRecentsRoot.authority = null;
mRecentsRoot.rootId = null;
mRecentsRoot.derivedIcon = R.drawable.ic_root_recent;
mRecentsRoot.flags = Root.FLAG_LOCAL_ONLY | Root.FLAG_SUPPORTS_CREATE
| Root.FLAG_SUPPORTS_IS_CHILD;
mRecentsRoot.title = mContext.getString(R.string.root_recent);
mRecentsRoot.availableBytes = -1;
new UpdateTask().executeOnExecutor(AsyncTask.THREAD_POOL_EXECUTOR);
}
/**
* Gather roots from storage providers belonging to given package name.
*/
public void updatePackageAsync(String packageName) {
new UpdateTask(packageName).executeOnExecutor(AsyncTask.THREAD_POOL_EXECUTOR);
}
/**
* Gather roots from storage providers belonging to given authority.
*/
public void updateAuthorityAsync(String authority) {
final ProviderInfo info = mContext.getPackageManager().resolveContentProvider(authority, 0);
if (info != null) {
updatePackageAsync(info.packageName);
}
}
private void waitForFirstLoad() {
boolean success = false;
try {
success = mFirstLoad.await(15, TimeUnit.SECONDS);
} catch (InterruptedException e) {
}
if (!success) {
Log.w(TAG, "Timeout waiting for first update");
}
}
/**
* Load roots from authorities that are in stopped state. Normal
* {@link UpdateTask} passes ignore stopped applications.
*/
private void loadStoppedAuthorities() {
final ContentResolver resolver = mContext.getContentResolver();
synchronized (mLock) {
for (String authority : mStoppedAuthorities) {
if (LOGD) Log.d(TAG, "Loading stopped authority " + authority);
mRoots.putAll(authority, loadRootsForAuthority(resolver, authority));
}
mStoppedAuthorities.clear();
}
}
private class UpdateTask extends AsyncTask<Void, Void, Void> {
private final String mFilterPackage;
private final Multimap<String, RootInfo> mTaskRoots = ArrayListMultimap.create();
private final HashSet<String> mTaskStoppedAuthorities = Sets.newHashSet();
/**
* Update all roots.
*/
public UpdateTask() {
this(null);
}
/**
* Only update roots belonging to given package name. Other roots will
* be copied from cached {@link #mRoots} values.
*/
public UpdateTask(String filterPackage) {
mFilterPackage = filterPackage;
}
@Override
protected Void doInBackground(Void... params) {
final long start = SystemClock.elapsedRealtime();
if (mFilterPackage != null) {
// Need at least first load, since we're going to be using
// previously cached values for non-matching packages.
waitForFirstLoad();
}
mTaskRoots.put(mRecentsRoot.authority, mRecentsRoot);
final ContentResolver resolver = mContext.getContentResolver();
final PackageManager pm = mContext.getPackageManager();
// Pick up provider with action string
final Intent intent = new Intent(DocumentsContract.PROVIDER_INTERFACE);
final List<ResolveInfo> providers = pm.queryIntentContentProviders(intent, 0);
for (ResolveInfo info : providers) {
handleDocumentsProvider(info.providerInfo);
}
final long delta = SystemClock.elapsedRealtime() - start;
Log.d(TAG, "Update found " + mTaskRoots.size() + " roots in " + delta + "ms");
synchronized (mLock) {
mRoots = mTaskRoots;
mStoppedAuthorities = mTaskStoppedAuthorities;
}
mFirstLoad.countDown();
resolver.notifyChange(sNotificationUri, null, false);
return null;
}
private void handleDocumentsProvider(ProviderInfo info) {
// Ignore stopped packages for now; we might query them
// later during UI interaction.
if ((info.applicationInfo.flags & ApplicationInfo.FLAG_STOPPED) != 0) {
if (LOGD) Log.d(TAG, "Ignoring stopped authority " + info.authority);
mTaskStoppedAuthorities.add(info.authority);
return;
}
// Try using cached roots if filtering
boolean cacheHit = false;
if (mFilterPackage != null && !mFilterPackage.equals(info.packageName)) {
synchronized (mLock) {
if (mTaskRoots.putAll(info.authority, mRoots.get(info.authority))) {
if (LOGD) Log.d(TAG, "Used cached roots for " + info.authority);
cacheHit = true;
}
}
}
// Cache miss, or loading everything
if (!cacheHit) {
mTaskRoots.putAll(info.authority,
loadRootsForAuthority(mContext.getContentResolver(), info.authority));
}
}
}
/**
* Bring up requested provider and query for all active roots.
*/
private Collection<RootInfo> loadRootsForAuthority(ContentResolver resolver, String authority) {
if (LOGD) Log.d(TAG, "Loading roots for " + authority);
synchronized (mObservedAuthorities) {
if (mObservedAuthorities.add(authority)) {
// Watch for any future updates
final Uri rootsUri = DocumentsContract.buildRootsUri(authority);
mContext.getContentResolver().registerContentObserver(rootsUri, true, mObserver);
}
}
final List<RootInfo> roots = Lists.newArrayList();
final Uri rootsUri = DocumentsContract.buildRootsUri(authority);
ContentProviderClient client = null;
Cursor cursor = null;
try {
client = DocumentsApplication.acquireUnstableProviderOrThrow(resolver, authority);
cursor = client.query(rootsUri, null, null, null, null);
while (cursor.moveToNext()) {
final RootInfo root = RootInfo.fromRootsCursor(authority, cursor);
roots.add(root);
}
} catch (Exception e) {
Log.w(TAG, "Failed to load some roots from " + authority + ": " + e);
} finally {
IoUtils.closeQuietly(cursor);
ContentProviderClient.releaseQuietly(client);
}
return roots;
}
/**
* Return the requested {@link RootInfo}, but only loading the roots for the
* requested authority. This is useful when we want to load fast without
* waiting for all the other roots to come back.
*/
public RootInfo getRootOneshot(String authority, String rootId) {
synchronized (mLock) {
RootInfo root = getRootLocked(authority, rootId);
if (root == null) {
mRoots.putAll(
authority, loadRootsForAuthority(mContext.getContentResolver(), authority));
root = getRootLocked(authority, rootId);
}
return root;
}
}
public RootInfo getRootBlocking(String authority, String rootId) {
waitForFirstLoad();
loadStoppedAuthorities();
synchronized (mLock) {
return getRootLocked(authority, rootId);
}
}
private RootInfo getRootLocked(String authority, String rootId) {
for (RootInfo root : mRoots.get(authority)) {
if (Objects.equals(root.rootId, rootId)) {
return root;
}
}
return null;
}
public boolean isIconUniqueBlocking(RootInfo root) {
waitForFirstLoad();
loadStoppedAuthorities();
synchronized (mLock) {
final int rootIcon = root.derivedIcon != 0 ? root.derivedIcon : root.icon;
for (RootInfo test : mRoots.get(root.authority)) {
if (Objects.equals(test.rootId, root.rootId)) {
continue;
}
final int testIcon = test.derivedIcon != 0 ? test.derivedIcon : test.icon;
if (testIcon == rootIcon) {
return false;
}
}
return true;
}
}
public RootInfo getRecentsRoot() {
return mRecentsRoot;
}
public boolean isRecentsRoot(RootInfo root) {
return mRecentsRoot == root;
}
public Collection<RootInfo> getRootsBlocking() {
waitForFirstLoad();
loadStoppedAuthorities();
synchronized (mLock) {
return mRoots.values();
}
}
public Collection<RootInfo> getMatchingRootsBlocking(State state) {
waitForFirstLoad();
loadStoppedAuthorities();
synchronized (mLock) {
return getMatchingRoots(mRoots.values(), state);
}
}
@VisibleForTesting
static List<RootInfo> getMatchingRoots(Collection<RootInfo> roots, State state) {
final List<RootInfo> matching = Lists.newArrayList();
for (RootInfo root : roots) {
final boolean supportsCreate = (root.flags & Root.FLAG_SUPPORTS_CREATE) != 0;
final boolean supportsIsChild = (root.flags & Root.FLAG_SUPPORTS_IS_CHILD) != 0;
final boolean advanced = (root.flags & Root.FLAG_ADVANCED) != 0;
final boolean localOnly = (root.flags & Root.FLAG_LOCAL_ONLY) != 0;
final boolean empty = (root.flags & Root.FLAG_EMPTY) != 0;
// Exclude read-only devices when creating
if (state.action == State.ACTION_CREATE && !supportsCreate) continue;
if (state.action == State.ACTION_OPEN_COPY_DESTINATION && !supportsCreate) continue;
// Exclude roots that don't support directory picking
if (state.action == State.ACTION_OPEN_TREE && !supportsIsChild) continue;
// Exclude advanced devices when not requested
if (!state.showAdvanced && advanced) continue;
// Exclude non-local devices when local only
if (state.localOnly && !localOnly) continue;
// Exclude downloads roots that don't support directory creation
// TODO: Add flag to check the root supports directory creation or not.
if (state.directoryCopy && root.isDownloads()) continue;
// Only show empty roots when creating
if ((state.action != State.ACTION_CREATE ||
state.action != State.ACTION_OPEN_TREE ||
state.action != State.ACTION_OPEN_COPY_DESTINATION) && empty) continue;
// Only include roots that serve requested content
final boolean overlap =
MimePredicate.mimeMatches(root.derivedMimeTypes, state.acceptMimes) ||
MimePredicate.mimeMatches(state.acceptMimes, root.derivedMimeTypes);
if (!overlap) {
continue;
}
// Exclude roots from the calling package.
if (state.excludedAuthorities.contains(root.authority)) {
if (LOGD) Log.d(TAG, "Excluding root " + root.authority + " from calling package.");
continue;
}
matching.add(root);
}
return matching;
}
}