[multi-part] Eliminate 1k selection limit (908f9889) · Commits · e / os / android_frameworks_base

packages/DocumentsUI/src/com/android/documentsui/ClipStorage.java

+172 −37

Original line number	Diff line number	Diff line
		@@ -16,9 +16,12 @@

		package com.android.documentsui;

		import android.content.SharedPreferences;
		import android.net.Uri;
		import android.os.AsyncTask;
		import android.support.annotation.VisibleForTesting;
		import android.system.ErrnoException;
		import android.system.Os;
		import android.util.Log;

		import java.io.Closeable;
		@@ -27,62 +30,157 @@ import java.io.FileInputStream;
		import java.io.FileOutputStream;
		import java.io.IOException;
		import java.nio.channels.FileLock;
		import java.util.HashMap;
		import java.util.Map;
		import java.util.Scanner;
		import java.util.concurrent.TimeUnit;

		/**
		* Provides support for storing lists of documents identified by Uri.
		*
		* <li>Access to this object must be synchronized externally.
		* <li>All calls to this class are I/O intensive and must be wrapped in an AsyncTask.
		* This class uses a ring buffer to recycle clip file slots, to mitigate the issue of clip file
		* deletions.
		*/
		public final class ClipStorage {

		public static final int NO_SELECTION_TAG = -1;

		static final String PREF_NAME = "ClipStoragePref";

		@VisibleForTesting
		static final int NUM_OF_SLOTS = 20;

		private static final String TAG = "ClipStorage";

		private static final long STALENESS_THRESHOLD = TimeUnit.DAYS.toMillis(2);

		private static final String NEXT_POS_TAG = "NextPosTag";
		private static final String PRIMARY_DATA_FILE_NAME = "primary";

		private static final byte[] LINE_SEPARATOR = System.lineSeparator().getBytes();
		public static final long NO_SELECTION_TAG = -1;

		private final File mOutDir;
		private final SharedPreferences mPref;

		private final File[] mSlots = new File[NUM_OF_SLOTS];
		private int mNextPos;

		/**
		* @param outDir see {@link #prepareStorage(File)}.
		*/
		public ClipStorage(File outDir) {
		public ClipStorage(File outDir, SharedPreferences pref) {
		assert(outDir.isDirectory());
		mOutDir = outDir;
		mPref = pref;

		mNextPos = mPref.getInt(NEXT_POS_TAG, 0);
		}

		/**
		* Creates a clip tag.
		* Tries to get the next available clip slot. It's guaranteed to return one. If none of
		* slots is available, it returns the next slot of the most recently returned slot by this
		* method.
		*
		* NOTE: this tag doesn't guarantee perfect uniqueness, but should work well unless user creates
		* clips more than hundreds of times per second.
		* <p>This is not a perfect solution, but should be enough for most regular use. There are
		* several situations this method may not work:
		* <ul>
		* <li>Making {@link #NUM_OF_SLOTS} - 1 times of large drag and drop or moveTo/copyTo/delete
		* operations after cutting a primary clip, then the primary clip is overwritten.</li>
		* <li>Having more than {@link #NUM_OF_SLOTS} queued jumbo file operations, one or more clip
		* file may be overwritten.</li>
		* </ul>
		*/
		public long createTag() {
		return System.currentTimeMillis();
		public synchronized int claimStorageSlot() {
		int curPos = mNextPos;
		for (int i = 0; i < NUM_OF_SLOTS; ++i, curPos = (curPos + 1) % NUM_OF_SLOTS) {
		createSlotFile(curPos);

		if (!mSlots[curPos].exists()) {
		break;
		}

		// No file or only primary file exists, we deem it available.
		if (mSlots[curPos].list().length <= 1) {
		break;
		}
		// This slot doesn't seem available, but still need to check if it's a legacy of
		// service being killed or a service crash etc. If it's stale, it's available.
		else if(checkStaleFiles(curPos)) {
		break;
		}
		}

		prepareSlot(curPos);

		mNextPos = (curPos + 1) % NUM_OF_SLOTS;
		mPref.edit().putInt(NEXT_POS_TAG, mNextPos).commit();
		return curPos;
		}

		private boolean checkStaleFiles(int pos) {
		File slotData = toSlotDataFile(pos);

		// No need to check if the file exists. File.lastModified() returns 0L if the file doesn't
		// exist.
		return slotData.lastModified() + STALENESS_THRESHOLD <= System.currentTimeMillis();
		}

		private void prepareSlot(int pos) {
		assert(mSlots[pos] != null);

		Files.deleteRecursively(mSlots[pos]);
		mSlots[pos].mkdir();
		assert(mSlots[pos].isDirectory());
		}

		/**
		* Returns a writer. Callers must close the writer when finished.
		*/
		public Writer createWriter(long tag) throws IOException {
		File file = toTagFile(tag);
		private Writer createWriter(int tag) throws IOException {
		File file = toSlotDataFile(tag);
		return new Writer(file);
		}

		@VisibleForTesting
		public Reader createReader(long tag) throws IOException {
		File file = toTagFile(tag);
		/**
		* Gets a {@link File} instance given a tag.
		*
		* This method creates a symbolic link in the slot folder to the data file as a reference
		* counting method. When someone is done using this symlink, it's responsible to delete it.
		* Therefore we can have a neat way to track how many things are still using this slot.
		*/
		public File getFile(int tag) throws IOException {
		createSlotFile(tag);

		File primary = toSlotDataFile(tag);

		String linkFileName = Integer.toString(mSlots[tag].list().length);
		File link = new File(mSlots[tag], linkFileName);

		try {
		Os.symlink(primary.getAbsolutePath(), link.getAbsolutePath());
		} catch (ErrnoException e) {
		e.rethrowAsIOException();
		}
		return link;
		}

		/**
		* Returns a Reader. Callers must close the reader when finished.
		*/
		public Reader createReader(File file) throws IOException {
		assert(file.getParentFile().getParentFile().equals(mOutDir));
		return new Reader(file);
		}

		@VisibleForTesting
		public void delete(long tag) throws IOException {
		toTagFile(tag).delete();
		private File toSlotDataFile(int pos) {
		assert(mSlots[pos] != null);
		return new File(mSlots[pos], PRIMARY_DATA_FILE_NAME);
		}

		private File toTagFile(long tag) {
		return new File(mOutDir, String.valueOf(tag));
		private void createSlotFile(int pos) {
		if (mSlots[pos] == null) {
		mSlots[pos] = new File(mOutDir, Integer.toString(pos));
		}
		}

		/**
		@@ -96,27 +194,39 @@ public final class ClipStorage {
		return clipDir;
		}

		public static boolean hasDocList(long tag) {
		return tag != NO_SELECTION_TAG;
		}

		private static File getClipDir(File cacheDir) {
		return new File(cacheDir, "clippings");
		}

		static final class Reader implements Iterable<Uri>, Closeable {

		/**
		* FileLock can't be held multiple times in a single JVM, but it's possible to have multiple
		* readers reading the same clip file. Share the FileLock here so that it can be released
		* when it's not needed.
		*/
		private static final Map<String, FileLockEntry> sLocks = new HashMap<>();

		private final String mCanonicalPath;
		private final Scanner mScanner;
		private final FileLock mLock;

		private Reader(File file) throws IOException {
		FileInputStream inStream = new FileInputStream(file);

		// Lock the file here so it won't pass this line until the corresponding writer is done
		// writing.
		mLock = inStream.getChannel().lock(0L, Long.MAX_VALUE, true);

		mScanner = new Scanner(inStream);

		mCanonicalPath = file.getCanonicalPath(); // Resolve symlink
		synchronized (sLocks) {
		if (sLocks.containsKey(mCanonicalPath)) {
		// Read lock is already held by someone in this JVM, just increment the ref
		// count.
		sLocks.get(mCanonicalPath).mCount++;
		} else {
		// No map entry, need to lock the file so it won't pass this line until the
		// corresponding writer is done writing.
		FileLock lock = inStream.getChannel().lock(0L, Long.MAX_VALUE, true);
		sLocks.put(mCanonicalPath, new FileLockEntry(1, lock, mScanner));
		}
		}
		}

		@Override
		@@ -126,15 +236,24 @@ public final class ClipStorage {

		@Override
		public void close() throws IOException {
		if (mLock != null) {
		mLock.release();
		synchronized (sLocks) {
		FileLockEntry ref = sLocks.get(mCanonicalPath);

		assert(ref.mCount > 0);
		if (--ref.mCount == 0) {
		// If ref count is 0 now, then there is no one who needs to hold the read lock.
		// Release the lock, and remove the entry.
		ref.mLock.release();
		ref.mScanner.close();
		sLocks.remove(mCanonicalPath);
		}

		if (mScanner != null) {
		if (mScanner != ref.mScanner) {
		mScanner.close();
		}
		}
		}
		}

		private static final class Iterator implements java.util.Iterator {
		private final Scanner mScanner;
		@@ -155,12 +274,28 @@ public final class ClipStorage {
		}
		}

		private static final class FileLockEntry {
		private int mCount;
		private FileLock mLock;
		// We need to keep this scanner here because if the scanner is closed, the file lock is
		// closed too.
		private Scanner mScanner;

		private FileLockEntry(int count, FileLock lock, Scanner scanner) {
		mCount = count;
		mLock = lock;
		mScanner = scanner;
		}
		}

		private static final class Writer implements Closeable {

		private final FileOutputStream mOut;
		private final FileLock mLock;

		private Writer(File file) throws IOException {
		assert(!file.exists());

		mOut = new FileOutputStream(file);

		// Lock the file here so copy tasks would wait until everything is flushed to disk
		@@ -192,9 +327,9 @@ public final class ClipStorage {

		private final ClipStorage mClipStorage;
		private final Iterable<Uri> mUris;
		private final long mTag;
		private final int mTag;

		PersistTask(ClipStorage clipStorage, Iterable<Uri> uris, long tag) {
		PersistTask(ClipStorage clipStorage, Iterable<Uri> uris, int tag) {
		mClipStorage = clipStorage;
		mUris = uris;
		mTag = tag;
		@@ -202,7 +337,7 @@ public final class ClipStorage {

		@Override
		protected Void doInBackground(Void... params) {
		try (ClipStorage.Writer writer = mClipStorage.createWriter(mTag)) {
		try(Writer writer = mClipStorage.createWriter(mTag)){
		for (Uri uri: mUris) {
		assert(uri != null);
		writer.write(uri);

packages/DocumentsUI/src/com/android/documentsui/DocumentClipper.java

+34 −151

Original line number	Diff line number	Diff line
		@@ -21,9 +21,7 @@ import android.content.ClipDescription;
		import android.content.ClipboardManager;
		import android.content.ContentResolver;
		import android.content.Context;
		import android.content.SharedPreferences;
		import android.net.Uri;
		import android.os.BaseBundle;
		import android.os.PersistableBundle;
		import android.provider.DocumentsContract;
		import android.support.annotation.Nullable;
		@@ -48,7 +46,7 @@ import java.util.function.Function;
		* ClipboardManager wrapper class providing higher level logical
		* support for dealing with Documents.
		*/
		public final class DocumentClipper implements ClipboardManager.OnPrimaryClipChangedListener {
		public final class DocumentClipper {

		private static final String TAG = "DocumentClipper";

		@@ -57,34 +55,14 @@ public final class DocumentClipper implements ClipboardManager.OnPrimaryClipChan
		static final String OP_JUMBO_SELECTION_SIZE = "jumboSelection-size";
		static final String OP_JUMBO_SELECTION_TAG = "jumboSelection-tag";

		// Use shared preference to store last seen primary clip tag, so that we can delete the file
		// when we realize primary clip has been changed when we're not running.
		private static final String PREF_NAME = "DocumentClipperPref";
		private static final String LAST_PRIMARY_CLIP_TAG = "lastPrimaryClipTag";

		private final Context mContext;
		private final ClipStorage mClipStorage;
		private final ClipboardManager mClipboard;

		// Here we're tracking the last clipped tag ids so we can delete them later.
		private long mLastDragClipTag = ClipStorage.NO_SELECTION_TAG;
		private long mLastUnusedPrimaryClipTag = ClipStorage.NO_SELECTION_TAG;

		private final SharedPreferences mPref;

		DocumentClipper(Context context, ClipStorage storage) {
		mContext = context;
		mClipStorage = storage;
		mClipboard = context.getSystemService(ClipboardManager.class);

		mClipboard.addPrimaryClipChangedListener(this);

		// Primary clips may be changed when we're not running, now it's time to clean up the
		// remnant.
		mPref = context.getSharedPreferences(PREF_NAME, 0);
		mLastUnusedPrimaryClipTag =
		mPref.getLong(LAST_PRIMARY_CLIP_TAG, ClipStorage.NO_SELECTION_TAG);
		deleteLastUnusedPrimaryClip();
		}

		public boolean hasItemsToPaste() {
		@@ -109,27 +87,11 @@ public final class DocumentClipper implements ClipboardManager.OnPrimaryClipChan
		return uri != null && DocumentsContract.isDocumentUri(mContext, uri);
		}

		/**
		* Returns {@link ClipData} representing the selection, or null if selection is empty,
		* or cannot be converted.
		*
		* This is specialized for drag and drop so that we know which file to delete if nobody accepts
		* the drop.
		*/
		public @Nullable ClipData getClipDataForDrag(
		Function<String, Uri> uriBuilder, Selection selection, @OpType int opType) {
		ClipData data = getClipDataForDocuments(uriBuilder, selection, opType);

		mLastDragClipTag = getTag(data);

		return data;
		}

		/**
		* Returns {@link ClipData} representing the selection, or null if selection is empty,
		* or cannot be converted.
		*/
		private @Nullable ClipData getClipDataForDocuments(
		public ClipData getClipDataForDocuments(
		Function<String, Uri> uriBuilder, Selection selection, @OpType int opType) {

		assert(selection != null);
		@@ -147,7 +109,7 @@ public final class DocumentClipper implements ClipboardManager.OnPrimaryClipChan
		/**
		* Returns ClipData representing the selection.
		*/
		private @Nullable ClipData createStandardClipData(
		private ClipData createStandardClipData(
		Function<String, Uri> uriBuilder, Selection selection, @OpType int opType) {

		assert(!selection.isEmpty());
		@@ -178,7 +140,7 @@ public final class DocumentClipper implements ClipboardManager.OnPrimaryClipChan
		/**
		* Returns ClipData representing the list of docs
		*/
		private @Nullable ClipData createJumboClipData(
		private ClipData createJumboClipData(
		Function<String, Uri> uriBuilder, Selection selection, @OpType int opType) {

		assert(!selection.isEmpty());
		@@ -210,8 +172,8 @@ public final class DocumentClipper implements ClipboardManager.OnPrimaryClipChan
		bundle.putInt(OP_JUMBO_SELECTION_SIZE, selection.size());

		// Creates a clip tag
		long tag = mClipStorage.createTag();
		bundle.putLong(OP_JUMBO_SELECTION_TAG, tag);
		int tag = mClipStorage.claimStorageSlot();
		bundle.putInt(OP_JUMBO_SELECTION_TAG, tag);

		ClipDescription description = new ClipDescription(
		"", // Currently "label" is not displayed anywhere in the UI.
		@@ -232,7 +194,7 @@ public final class DocumentClipper implements ClipboardManager.OnPrimaryClipChan
		getClipDataForDocuments(uriBuilder, selection, FileOperationService.OPERATION_COPY);
		assert(data != null);

		setPrimaryClip(data);
		mClipboard.setPrimaryClip(data);
		}

		/**
		@@ -250,67 +212,9 @@ public final class DocumentClipper implements ClipboardManager.OnPrimaryClipChan
		PersistableBundle bundle = data.getDescription().getExtras();
		bundle.putString(SRC_PARENT_KEY, parent.derivedUri.toString());

		setPrimaryClip(data);
		}

		private void setPrimaryClip(ClipData data) {
		deleteLastPrimaryClip();

		long tag = getTag(data);
		setLastUnusedPrimaryClipTag(tag);

		mClipboard.setPrimaryClip(data);
		}

		/**
		* Sets this primary tag to both class variable and shared preference.
		*/
		private void setLastUnusedPrimaryClipTag(long tag) {
		mLastUnusedPrimaryClipTag = tag;
		mPref.edit().putLong(LAST_PRIMARY_CLIP_TAG, tag).commit();
		}

		/**
		* This is a good chance for us to remove previous clip file for cut/copy because we know a new
		* primary clip is set.
		*/
		@Override
		public void onPrimaryClipChanged() {
		deleteLastUnusedPrimaryClip();
		}

		private void deleteLastUnusedPrimaryClip() {
		ClipData primary = mClipboard.getPrimaryClip();
		long primaryTag = getTag(primary);

		// onPrimaryClipChanged is also called after we call setPrimaryClip(), so make sure we don't
		// delete the clip file we just created.
		if (mLastUnusedPrimaryClipTag != primaryTag) {
		deleteLastPrimaryClip();
		}
		}

		private void deleteLastPrimaryClip() {
		deleteClip(mLastUnusedPrimaryClipTag);
		setLastUnusedPrimaryClipTag(ClipStorage.NO_SELECTION_TAG);
		}

		/**
		* Deletes the last seen drag clip file.
		*/
		public void deleteDragClip() {
		deleteClip(mLastDragClipTag);
		mLastDragClipTag = ClipStorage.NO_SELECTION_TAG;
		}

		private void deleteClip(long tag) {
		try {
		mClipStorage.delete(tag);
		} catch (IOException e) {
		Log.w(TAG, "Error deleting clip file with tag: " + tag, e);
		}
		}

		/**
		* Copies documents from clipboard. It's the same as {@link #copyFromClipData} with clipData
		* returned from {@link ClipboardManager#getPrimaryClip()}.
		@@ -324,10 +228,6 @@ public final class DocumentClipper implements ClipboardManager.OnPrimaryClipChan
		DocumentStack docStack,
		FileOperations.Callback callback) {

		// The primary clip has been claimed by a file operation. It's now the operation's duty
		// to make sure the clip file is deleted after use.
		setLastUnusedPrimaryClipTag(ClipStorage.NO_SELECTION_TAG);

		copyFromClipData(destination, docStack, mClipboard.getPrimaryClip(), callback);
		}

		@@ -352,8 +252,8 @@ public final class DocumentClipper implements ClipboardManager.OnPrimaryClipChan

		PersistableBundle bundle = clipData.getDescription().getExtras();
		@OpType int opType = getOpType(bundle);
		UrisSupplier uris = UrisSupplier.create(clipData);

		try {
		UrisSupplier uris = UrisSupplier.create(clipData, mContext);
		if (!canCopy(destination)) {
		callback.onOperationResult(
		FileOperations.Callback.STATUS_REJECTED, opType, 0);
		@@ -379,6 +279,11 @@ public final class DocumentClipper implements ClipboardManager.OnPrimaryClipChan
		.build();

		FileOperations.start(mContext, operation, callback);
		} catch(IOException e) {
		Log.e(TAG, "Cannot create uris supplier.", e);
		callback.onOperationResult(FileOperations.Callback.STATUS_REJECTED, opType, 0);
		return;
		}
		}

		/**
		@@ -397,28 +302,6 @@ public final class DocumentClipper implements ClipboardManager.OnPrimaryClipChan
		return true;
		}

		/**
		* Obtains tag from {@link ClipData}. Returns {@link ClipStorage#NO_SELECTION_TAG}
		* if it's not a jumbo clip.
		*/
		private static long getTag(@Nullable ClipData data) {
		if (data == null) {
		return ClipStorage.NO_SELECTION_TAG;
		}

		ClipDescription description = data.getDescription();
		if (description == null) {
		return ClipStorage.NO_SELECTION_TAG;
		}

		BaseBundle bundle = description.getExtras();
		if (bundle == null) {
		return ClipStorage.NO_SELECTION_TAG;
		}

		return bundle.getLong(OP_JUMBO_SELECTION_TAG, ClipStorage.NO_SELECTION_TAG);
		}

		public static @OpType int getOpType(ClipData data) {
		PersistableBundle bundle = data.getDescription().getExtras();
		return getOpType(bundle);

packages/DocumentsUI/src/com/android/documentsui/DocumentsApplication.java

+3 −1

Original line number	Diff line number	Diff line
		@@ -77,7 +77,9 @@ public class DocumentsApplication extends Application {

		mThumbnailCache = new ThumbnailCache(memoryClassBytes / 4);

		mClipStorage = new ClipStorage(ClipStorage.prepareStorage(getCacheDir()));
		mClipStorage = new ClipStorage(
		ClipStorage.prepareStorage(getCacheDir()),
		getSharedPreferences(ClipStorage.PREF_NAME, 0));
		mClipper = new DocumentClipper(this, mClipStorage);

		final IntentFilter packageFilter = new IntentFilter();

packages/DocumentsUI/src/com/android/documentsui/Files.java

+4 −6

Original line number	Diff line number	Diff line
		@@ -26,7 +26,6 @@ public final class Files {
		private Files() {} // no initialization for utility classes.

		public static void deleteRecursively(File file) {
		if (file.exists()) {
		if (file.isDirectory()) {
		for (File child : file.listFiles()) {
		deleteRecursively(child);
		@@ -35,4 +34,3 @@ public final class Files {
		file.delete();
		}
		}
		}

packages/DocumentsUI/src/com/android/documentsui/UrisSupplier.java

+38 −33

File changed.

Preview size limit exceeded, changes collapsed.