100c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen/* 200c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen * Copyright (C) 2009 The Android Open Source Project 300c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen * 400c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen * Licensed under the Apache License, Version 2.0 (the "License"); 500c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen * you may not use this file except in compliance with the License. 600c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen * You may obtain a copy of the License at 700c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen * 800c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen * http://www.apache.org/licenses/LICENSE-2.0 900c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen * 1000c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen * Unless required by applicable law or agreed to in writing, software 1100c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen * distributed under the License is distributed on an "AS IS" BASIS, 1200c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 1300c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen * See the License for the specific language governing permissions and 1400c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen * limitations under the License. 1500c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen */ 1600c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen 1700c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chenpackage android.media; 1800c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen 1900c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chenimport android.graphics.Bitmap; 2000c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chenimport android.net.Uri; 2100c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chenimport android.os.Environment; 2200c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chenimport android.util.Log; 2300c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen 2400c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chenimport java.io.File; 2500c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chenimport java.io.IOException; 2600c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chenimport java.io.RandomAccessFile; 27ecc97cc9491f40c507e372a30bcd58a9e08066a8Ray Chenimport java.nio.ByteBuffer; 2800c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chenimport java.nio.channels.FileChannel; 2900c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chenimport java.nio.channels.FileLock; 3000c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chenimport java.util.Hashtable; 3100c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen 3200c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen/** 3300c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen * This class handles the mini-thumb file. A mini-thumb file consists 3400c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen * of blocks, indexed by id. Each block has BYTES_PER_MINTHUMB bytes in the 3500c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen * following format: 3600c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen * 3700c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen * 1 byte status (0 = empty, 1 = mini-thumb available) 3800c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen * 8 bytes magic (a magic number to match what's in the database) 3900c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen * 4 bytes data length (LEN) 4000c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen * LEN bytes jpeg data 4100c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen * (the remaining bytes are unused) 4200c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen * 4300c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen * @hide This file is shared between MediaStore and MediaProvider and should remained internal use 4400c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen * only. 4500c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen */ 4600c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chenpublic class MiniThumbFile { 4700c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen private static final String TAG = "MiniThumbFile"; 4800c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen private static final int MINI_THUMB_DATA_FILE_VERSION = 3; 4900c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen public static final int BYTES_PER_MINTHUMB = 10000; 5000c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen private static final int HEADER_SIZE = 1 + 8 + 4; 5100c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen private Uri mUri; 5200c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen private RandomAccessFile mMiniThumbFile; 5300c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen private FileChannel mChannel; 54ecc97cc9491f40c507e372a30bcd58a9e08066a8Ray Chen private ByteBuffer mBuffer; 5530c918ce7fbe171944b28fc91b3f22b3d631872dGlenn Kasten private static final Hashtable<String, MiniThumbFile> sThumbFiles = 5600c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen new Hashtable<String, MiniThumbFile>(); 5700c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen 5800c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen /** 5900c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen * We store different types of thumbnails in different files. To remain backward compatibility, 6000c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen * we should hashcode of content://media/external/images/media remains the same. 6100c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen */ 6200c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen public static synchronized void reset() { 63ef093cd6c4ab4d3c8a1c8be5ed7147d5f06d7027Ray Chen for (MiniThumbFile file : sThumbFiles.values()) { 64ef093cd6c4ab4d3c8a1c8be5ed7147d5f06d7027Ray Chen file.deactivate(); 65ef093cd6c4ab4d3c8a1c8be5ed7147d5f06d7027Ray Chen } 6600c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen sThumbFiles.clear(); 6700c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen } 6800c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen 6900c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen public static synchronized MiniThumbFile instance(Uri uri) { 7000c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen String type = uri.getPathSegments().get(1); 7100c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen MiniThumbFile file = sThumbFiles.get(type); 7200c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen // Log.v(TAG, "get minithumbfile for type: "+type); 7300c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen if (file == null) { 7400c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen file = new MiniThumbFile( 7500c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen Uri.parse("content://media/external/" + type + "/media")); 7600c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen sThumbFiles.put(type, file); 7700c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen } 7800c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen 7900c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen return file; 8000c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen } 8100c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen 8200c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen private String randomAccessFilePath(int version) { 8300c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen String directoryName = 8400c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen Environment.getExternalStorageDirectory().toString() 8500c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen + "/DCIM/.thumbnails"; 8600c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen return directoryName + "/.thumbdata" + version + "-" + mUri.hashCode(); 8700c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen } 8800c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen 8900c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen private void removeOldFile() { 9000c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen String oldPath = randomAccessFilePath(MINI_THUMB_DATA_FILE_VERSION - 1); 9100c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen File oldFile = new File(oldPath); 9200c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen if (oldFile.exists()) { 9300c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen try { 9400c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen oldFile.delete(); 9500c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen } catch (SecurityException ex) { 9600c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen // ignore 9700c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen } 9800c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen } 9900c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen } 10000c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen 10100c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen private RandomAccessFile miniThumbDataFile() { 10200c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen if (mMiniThumbFile == null) { 10300c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen removeOldFile(); 10400c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen String path = randomAccessFilePath(MINI_THUMB_DATA_FILE_VERSION); 10500c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen File directory = new File(path).getParentFile(); 10600c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen if (!directory.isDirectory()) { 10700c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen if (!directory.mkdirs()) { 10800c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen Log.e(TAG, "Unable to create .thumbnails directory " 10900c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen + directory.toString()); 11000c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen } 11100c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen } 11200c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen File f = new File(path); 11300c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen try { 11400c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen mMiniThumbFile = new RandomAccessFile(f, "rw"); 11500c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen } catch (IOException ex) { 11600c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen // Open as read-only so we can at least read the existing 11700c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen // thumbnails. 11800c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen try { 11900c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen mMiniThumbFile = new RandomAccessFile(f, "r"); 12000c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen } catch (IOException ex2) { 12100c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen // ignore exception 12200c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen } 12300c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen } 124f5722b3f22e016a8f21c628776cd0746ef164c19Chih-Chung Chang if (mMiniThumbFile != null) { 125f5722b3f22e016a8f21c628776cd0746ef164c19Chih-Chung Chang mChannel = mMiniThumbFile.getChannel(); 126f5722b3f22e016a8f21c628776cd0746ef164c19Chih-Chung Chang } 12700c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen } 12800c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen return mMiniThumbFile; 12900c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen } 13000c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen 13100c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen public MiniThumbFile(Uri uri) { 13200c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen mUri = uri; 133ecc97cc9491f40c507e372a30bcd58a9e08066a8Ray Chen mBuffer = ByteBuffer.allocateDirect(BYTES_PER_MINTHUMB); 13400c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen } 13500c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen 13600c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen public synchronized void deactivate() { 13700c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen if (mMiniThumbFile != null) { 13800c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen try { 13900c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen mMiniThumbFile.close(); 14000c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen mMiniThumbFile = null; 14100c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen } catch (IOException ex) { 14200c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen // ignore exception 14300c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen } 14400c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen } 14500c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen } 14600c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen 14700c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen // Get the magic number for the specified id in the mini-thumb file. 14800c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen // Returns 0 if the magic is not available. 149ef093cd6c4ab4d3c8a1c8be5ed7147d5f06d7027Ray Chen public synchronized long getMagic(long id) { 15000c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen // check the mini thumb file for the right data. Right is 15100c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen // defined as having the right magic number at the offset 15200c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen // reserved for this "id". 15300c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen RandomAccessFile r = miniThumbDataFile(); 15400c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen if (r != null) { 15500c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen long pos = id * BYTES_PER_MINTHUMB; 15600c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen FileLock lock = null; 15700c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen try { 158ecc97cc9491f40c507e372a30bcd58a9e08066a8Ray Chen mBuffer.clear(); 159ecc97cc9491f40c507e372a30bcd58a9e08066a8Ray Chen mBuffer.limit(1 + 8); 160ecc97cc9491f40c507e372a30bcd58a9e08066a8Ray Chen 161ecc97cc9491f40c507e372a30bcd58a9e08066a8Ray Chen lock = mChannel.lock(pos, 1 + 8, true); 16200c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen // check that we can read the following 9 bytes 16300c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen // (1 for the "status" and 8 for the long) 164ecc97cc9491f40c507e372a30bcd58a9e08066a8Ray Chen if (mChannel.read(mBuffer, pos) == 9) { 165ecc97cc9491f40c507e372a30bcd58a9e08066a8Ray Chen mBuffer.position(0); 166ecc97cc9491f40c507e372a30bcd58a9e08066a8Ray Chen if (mBuffer.get() == 1) { 167ecc97cc9491f40c507e372a30bcd58a9e08066a8Ray Chen return mBuffer.getLong(); 16800c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen } 16900c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen } 17000c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen } catch (IOException ex) { 17100c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen Log.v(TAG, "Got exception checking file magic: ", ex); 17200c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen } catch (RuntimeException ex) { 17300c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen // Other NIO related exception like disk full, read only channel..etc 17400c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen Log.e(TAG, "Got exception when reading magic, id = " + id + 17500c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen ", disk full or mount read-only? " + ex.getClass()); 17600c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen } finally { 17700c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen try { 17800c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen if (lock != null) lock.release(); 17900c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen } 18000c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen catch (IOException ex) { 18100c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen // ignore it. 18200c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen } 18300c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen } 18400c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen } 18500c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen return 0; 18600c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen } 18700c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen 188ef093cd6c4ab4d3c8a1c8be5ed7147d5f06d7027Ray Chen public synchronized void saveMiniThumbToFile(byte[] data, long id, long magic) 18900c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen throws IOException { 19000c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen RandomAccessFile r = miniThumbDataFile(); 19100c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen if (r == null) return; 19200c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen 19300c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen long pos = id * BYTES_PER_MINTHUMB; 19400c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen FileLock lock = null; 19500c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen try { 19600c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen if (data != null) { 19700c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen if (data.length > BYTES_PER_MINTHUMB - HEADER_SIZE) { 19800c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen // not enough space to store it. 19900c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen return; 20000c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen } 201ecc97cc9491f40c507e372a30bcd58a9e08066a8Ray Chen mBuffer.clear(); 202ecc97cc9491f40c507e372a30bcd58a9e08066a8Ray Chen mBuffer.put((byte) 1); 203ecc97cc9491f40c507e372a30bcd58a9e08066a8Ray Chen mBuffer.putLong(magic); 204ecc97cc9491f40c507e372a30bcd58a9e08066a8Ray Chen mBuffer.putInt(data.length); 205ecc97cc9491f40c507e372a30bcd58a9e08066a8Ray Chen mBuffer.put(data); 206ecc97cc9491f40c507e372a30bcd58a9e08066a8Ray Chen mBuffer.flip(); 20700c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen 208ecc97cc9491f40c507e372a30bcd58a9e08066a8Ray Chen lock = mChannel.lock(pos, BYTES_PER_MINTHUMB, false); 209ecc97cc9491f40c507e372a30bcd58a9e08066a8Ray Chen mChannel.write(mBuffer, pos); 21000c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen } 21100c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen } catch (IOException ex) { 21200c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen Log.e(TAG, "couldn't save mini thumbnail data for " 21300c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen + id + "; ", ex); 21400c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen throw ex; 21500c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen } catch (RuntimeException ex) { 21600c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen // Other NIO related exception like disk full, read only channel..etc 21700c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen Log.e(TAG, "couldn't save mini thumbnail data for " 21800c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen + id + "; disk full or mount read-only? " + ex.getClass()); 21900c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen } finally { 22000c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen try { 22100c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen if (lock != null) lock.release(); 22200c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen } 22300c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen catch (IOException ex) { 22400c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen // ignore it. 22500c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen } 22600c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen } 22700c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen } 22800c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen 22900c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen /** 23000c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen * Gallery app can use this method to retrieve mini-thumbnail. Full size 23100c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen * images share the same IDs with their corresponding thumbnails. 23200c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen * 23300c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen * @param id the ID of the image (same of full size image). 23400c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen * @param data the buffer to store mini-thumbnail. 23500c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen */ 236ef093cd6c4ab4d3c8a1c8be5ed7147d5f06d7027Ray Chen public synchronized byte [] getMiniThumbFromFile(long id, byte [] data) { 23700c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen RandomAccessFile r = miniThumbDataFile(); 23800c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen if (r == null) return null; 23900c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen 24000c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen long pos = id * BYTES_PER_MINTHUMB; 24100c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen FileLock lock = null; 24200c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen try { 243ecc97cc9491f40c507e372a30bcd58a9e08066a8Ray Chen mBuffer.clear(); 244ecc97cc9491f40c507e372a30bcd58a9e08066a8Ray Chen lock = mChannel.lock(pos, BYTES_PER_MINTHUMB, true); 245ecc97cc9491f40c507e372a30bcd58a9e08066a8Ray Chen int size = mChannel.read(mBuffer, pos); 246ecc97cc9491f40c507e372a30bcd58a9e08066a8Ray Chen if (size > 1 + 8 + 4) { // flag, magic, length 247ecc97cc9491f40c507e372a30bcd58a9e08066a8Ray Chen mBuffer.position(0); 248ecc97cc9491f40c507e372a30bcd58a9e08066a8Ray Chen byte flag = mBuffer.get(); 249ecc97cc9491f40c507e372a30bcd58a9e08066a8Ray Chen long magic = mBuffer.getLong(); 250ecc97cc9491f40c507e372a30bcd58a9e08066a8Ray Chen int length = mBuffer.getInt(); 251ecc97cc9491f40c507e372a30bcd58a9e08066a8Ray Chen 252ecc97cc9491f40c507e372a30bcd58a9e08066a8Ray Chen if (size >= 1 + 8 + 4 + length && data.length >= length) { 253ecc97cc9491f40c507e372a30bcd58a9e08066a8Ray Chen mBuffer.get(data, 0, length); 254ecc97cc9491f40c507e372a30bcd58a9e08066a8Ray Chen return data; 255ecc97cc9491f40c507e372a30bcd58a9e08066a8Ray Chen } 25600c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen } 25700c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen } catch (IOException ex) { 258ecc97cc9491f40c507e372a30bcd58a9e08066a8Ray Chen Log.w(TAG, "got exception when reading thumbnail id=" + id + ", exception: " + ex); 25900c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen } catch (RuntimeException ex) { 26000c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen // Other NIO related exception like disk full, read only channel..etc 26100c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen Log.e(TAG, "Got exception when reading thumbnail, id = " + id + 26200c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen ", disk full or mount read-only? " + ex.getClass()); 26300c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen } finally { 26400c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen try { 26500c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen if (lock != null) lock.release(); 26600c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen } 26700c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen catch (IOException ex) { 26800c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen // ignore it. 26900c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen } 27000c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen } 27100c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen return null; 27200c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen } 27300c575a3fccb9d3065e913f1b8fcf93e18d44eafRay Chen} 274