Merge "Rework thumbnail handling" into jellybean (d9939f4d) · Commits · e / os / android_frameworks_base

media/java/android/media/MiniThumbFile.java

+160 −3

Original line number	Diff line number	Diff line
		@@ -45,8 +45,14 @@ import java.util.Hashtable;
		*/
		public class MiniThumbFile {
		private static final String TAG = "MiniThumbFile";
		private static final int MINI_THUMB_DATA_FILE_VERSION = 3;
		private static final int MINI_THUMB_DATA_FILE_VERSION = 4;
		public static final int BYTES_PER_MINTHUMB = 10000;

		private static final int BYTES_PER_MINTHUMB_INDEX = 8;
		private FileChannel mIndexChannel;
		private RandomAccessFile mMiniThumbIndexFile;
		private final boolean debug = false;;

		private static final int HEADER_SIZE = 1 + 8 + 4;
		private Uri mUri;
		private RandomAccessFile mMiniThumbFile;
		@@ -98,6 +104,57 @@ public class MiniThumbFile {
		}
		}

		private String randomAccessIndexFilePath(int version) {
		String directoryName =
		Environment.getExternalStorageDirectory().toString()
		+ "/DCIM/.thumbnails";
		return directoryName + "/.thumbindex" + version + "-" + mUri.hashCode();
		}

		private void removeOldIndexFile() {
		String oldPath = randomAccessIndexFilePath(MINI_THUMB_DATA_FILE_VERSION - 1);
		File oldFile = new File(oldPath);
		if (oldFile.exists()) {
		try {
		oldFile.delete();
		} catch (SecurityException ex) {
		// ignore
		}
		}
		}

		private RandomAccessFile miniThumbIndexFile() {
		if (mMiniThumbIndexFile == null) {
		removeOldIndexFile();
		String path = randomAccessIndexFilePath(MINI_THUMB_DATA_FILE_VERSION);
		File directory = new File(path).getParentFile();
		if (!directory.isDirectory()) {
		if (!directory.mkdirs()) {
		Log.e(TAG, "Unable to create .thumbnails directory "
		+ directory.toString());
		}
		}
		File f = new File(path);

		try {
		mMiniThumbIndexFile = new RandomAccessFile(f, "rw");
		} catch (IOException ex) {
		// Open as read-only so we can at least read the existing
		// thumbnails.
		try {
		mMiniThumbIndexFile = new RandomAccessFile(f, "r");
		} catch (IOException ex2) {
		// ignore exception
		Log.e(TAG, "miniThumbIndexFile open r exception: " + f);
		}
		}
		if (mMiniThumbIndexFile != null) {
		mIndexChannel = mMiniThumbIndexFile.getChannel();
		}
		}
		return mMiniThumbIndexFile;
		}

		private RandomAccessFile miniThumbDataFile() {
		if (mMiniThumbFile == null) {
		removeOldFile();
		@@ -128,6 +185,8 @@ public class MiniThumbFile {
		return mMiniThumbFile;
		}



		public MiniThumbFile(Uri uri) {
		mUri = uri;
		mBuffer = ByteBuffer.allocateDirect(BYTES_PER_MINTHUMB);
		@@ -144,6 +203,94 @@ public class MiniThumbFile {
		}
		}

		/**
		* Get the index of thumbnail, which is the real saving location.
		* @param id the raw id in Mediaprovider database.
		* @param create when you want to create a new thumbnail, set to true; when generally query
		* thumbnail saved index, set to false.
		*/
		private long getIndex(long id, boolean create){
		RandomAccessFile r = miniThumbIndexFile();
		ByteBuffer buf = ByteBuffer.allocateDirect(BYTES_PER_MINTHUMB_INDEX);

		if (r != null) {
		long pos = 0;
		//first 8 bytes are for saving next create thumbnail block number!
		//so if create set, then begin from 0, others begin from real index
		// (id+1)*BYTES_PER_MINTHUMB_INDEX.
		if (!create) {
		pos = (id + 1) * BYTES_PER_MINTHUMB_INDEX;
		}

		FileLock lock = null;
		try {
		buf.clear();
		buf.limit(BYTES_PER_MINTHUMB_INDEX);

		lock = mIndexChannel.lock(pos, BYTES_PER_MINTHUMB_INDEX, false);
		//check that we can read the following 8 bytes
		//which is the index position of thumbnail.

		int read = mIndexChannel.read(buf, pos);

		if (read == BYTES_PER_MINTHUMB_INDEX) {
		buf.position(0);
		if (create) {
		//first, write next index.
		long now = buf.getLong();
		buf.clear();
		buf.position(0);
		buf.putLong(++now);
		buf.flip();
		int write = mIndexChannel.write(buf, pos);

		//second, write this id's index
		if(BYTES_PER_MINTHUMB_INDEX == write) {
		if (lock != null) lock.release();
		pos = (id + 1) * BYTES_PER_MINTHUMB_INDEX;
		lock = mIndexChannel.lock(pos, BYTES_PER_MINTHUMB_INDEX, false);
		buf.flip();
		write = mIndexChannel.write(buf, pos);
		if(debug) Log.d(TAG, "getIndex with create. index: " + now +
		"corresponding id: " + id + ", index is: " + pos);
		}
		return now;
		} else {
		long p = buf.getLong();
		if(debug) Log.d(TAG, "getIndex with no create. index: " + p);
		return p;
		}
		} else if(-1 == read) {
		//If the index file is empty, initialize first index to 0.
		if(0 == r.length()){
		buf.clear();
		buf.position(0);
		buf.putLong(0);
		buf.flip();
		int write = mIndexChannel.write(buf, 0);
		if(debug) Log.d(TAG, "initialize first index");
		if(BYTES_PER_MINTHUMB_INDEX == write) return 0;
		}
		}
		} catch (IOException ex) {
		Log.e(TAG, "Got exception checking file index: ", ex);
		} catch (RuntimeException ex) {
		// Other NIO related exception like disk full, read only channel..etc
		Log.e(TAG, "Got exception when reading index, id = " + id +
		", disk full or mount read-only? " + ex.getClass());
		} finally {
		try {
		if (lock != null) lock.release();
		}
		catch (IOException ex) {
		// ignore it.
		Log.e(TAG, "release lock: ", ex);
		}
		}
		}
		return 0;
		}

		// Get the magic number for the specified id in the mini-thumb file.
		// Returns 0 if the magic is not available.
		public synchronized long getMagic(long id) {
		@@ -151,8 +298,14 @@ public class MiniThumbFile {
		// defined as having the right magic number at the offset
		// reserved for this "id".
		RandomAccessFile r = miniThumbDataFile();

		if (r != null) {
		long pos = id * BYTES_PER_MINTHUMB;

		long pos = getIndex(id, false);
		if(pos < 0) return 0;

		pos *= BYTES_PER_MINTHUMB;

		FileLock lock = null;
		try {
		mBuffer.clear();
		@@ -190,7 +343,11 @@ public class MiniThumbFile {
		RandomAccessFile r = miniThumbDataFile();
		if (r == null) return;

		long pos = id * BYTES_PER_MINTHUMB;

		long pos = getIndex(id, true);
		if(pos < 0) return;

		pos *= BYTES_PER_MINTHUMB;
		FileLock lock = null;
		try {
		if (data != null) {