Daichi Hirono | fda7474 | 2016-02-01 13:00:31 +0900 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2016 The Android Open Source Project |
| 3 | * |
| 4 | * Licensed under the Apache License, Version 2.0 (the "License"); |
| 5 | * you may not use this file except in compliance with the License. |
| 6 | * You may obtain a copy of the License at |
| 7 | * |
| 8 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 9 | * |
| 10 | * Unless required by applicable law or agreed to in writing, software |
| 11 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 13 | * See the License for the specific language governing permissions and |
| 14 | * limitations under the License. |
| 15 | */ |
| 16 | |
Daichi Hirono | 8b9024f | 2015-08-12 12:59:09 +0900 | [diff] [blame] | 17 | package com.android.mtp; |
| 18 | |
| 19 | import android.content.ContentResolver; |
| 20 | import android.net.Uri; |
| 21 | import android.os.Process; |
| 22 | import android.provider.DocumentsContract; |
| 23 | import android.util.Log; |
| 24 | |
Daichi Hirono | 619afda | 2016-02-07 14:23:43 +0900 | [diff] [blame] | 25 | import java.io.FileNotFoundException; |
Daichi Hirono | fda7474 | 2016-02-01 13:00:31 +0900 | [diff] [blame] | 26 | import java.util.concurrent.CountDownLatch; |
Daichi Hirono | e1d5771 | 2015-11-17 10:55:45 +0900 | [diff] [blame] | 27 | import java.util.concurrent.ExecutorService; |
| 28 | import java.util.concurrent.Executors; |
| 29 | import java.util.concurrent.FutureTask; |
| 30 | import java.util.concurrent.TimeUnit; |
Daichi Hirono | 8b9024f | 2015-08-12 12:59:09 +0900 | [diff] [blame] | 31 | |
| 32 | final class RootScanner { |
| 33 | /** |
| 34 | * Polling interval in milliseconds used for first SHORT_POLLING_TIMES because it is more |
| 35 | * likely to add new root just after the device is added. |
| 36 | */ |
| 37 | private final static long SHORT_POLLING_INTERVAL = 2000; |
| 38 | |
| 39 | /** |
| 40 | * Polling interval in milliseconds for low priority polling, when changes are not expected. |
| 41 | */ |
| 42 | private final static long LONG_POLLING_INTERVAL = 30 * 1000; |
| 43 | |
| 44 | /** |
| 45 | * @see #SHORT_POLLING_INTERVAL |
| 46 | */ |
| 47 | private final static long SHORT_POLLING_TIMES = 10; |
| 48 | |
Daichi Hirono | e1d5771 | 2015-11-17 10:55:45 +0900 | [diff] [blame] | 49 | /** |
| 50 | * Milliseconds we wait for background thread when pausing. |
| 51 | */ |
| 52 | private final static long AWAIT_TERMINATION_TIMEOUT = 2000; |
| 53 | |
Daichi Hirono | 8b9024f | 2015-08-12 12:59:09 +0900 | [diff] [blame] | 54 | final ContentResolver mResolver; |
| 55 | final MtpManager mManager; |
Daichi Hirono | dc47344 | 2015-11-13 15:42:28 +0900 | [diff] [blame] | 56 | final MtpDatabase mDatabase; |
Daichi Hirono | e1d5771 | 2015-11-17 10:55:45 +0900 | [diff] [blame] | 57 | |
| 58 | ExecutorService mExecutor; |
| 59 | FutureTask<Void> mCurrentTask; |
Daichi Hirono | 8b9024f | 2015-08-12 12:59:09 +0900 | [diff] [blame] | 60 | |
Daichi Hirono | dc47344 | 2015-11-13 15:42:28 +0900 | [diff] [blame] | 61 | RootScanner( |
| 62 | ContentResolver resolver, |
Daichi Hirono | dc47344 | 2015-11-13 15:42:28 +0900 | [diff] [blame] | 63 | MtpManager manager, |
| 64 | MtpDatabase database) { |
Daichi Hirono | 8b9024f | 2015-08-12 12:59:09 +0900 | [diff] [blame] | 65 | mResolver = resolver; |
| 66 | mManager = manager; |
Daichi Hirono | dc47344 | 2015-11-13 15:42:28 +0900 | [diff] [blame] | 67 | mDatabase = database; |
Daichi Hirono | 8b9024f | 2015-08-12 12:59:09 +0900 | [diff] [blame] | 68 | } |
| 69 | |
Daichi Hirono | e1d5771 | 2015-11-17 10:55:45 +0900 | [diff] [blame] | 70 | /** |
| 71 | * Notifies a change of the roots list via ContentResolver. |
| 72 | */ |
Daichi Hirono | dc47344 | 2015-11-13 15:42:28 +0900 | [diff] [blame] | 73 | void notifyChange() { |
Daichi Hirono | ebd2405 | 2016-02-06 21:05:57 +0900 | [diff] [blame] | 74 | final Uri uri = DocumentsContract.buildRootsUri(MtpDocumentsProvider.AUTHORITY); |
Daichi Hirono | dc47344 | 2015-11-13 15:42:28 +0900 | [diff] [blame] | 75 | mResolver.notifyChange(uri, null, false); |
Daichi Hirono | 8b9024f | 2015-08-12 12:59:09 +0900 | [diff] [blame] | 76 | } |
| 77 | |
| 78 | /** |
| 79 | * Starts to check new changes right away. |
Daichi Hirono | 8b9024f | 2015-08-12 12:59:09 +0900 | [diff] [blame] | 80 | */ |
Daichi Hirono | fda7474 | 2016-02-01 13:00:31 +0900 | [diff] [blame] | 81 | synchronized CountDownLatch resume() { |
Daichi Hirono | e1d5771 | 2015-11-17 10:55:45 +0900 | [diff] [blame] | 82 | if (mExecutor == null) { |
| 83 | // Only single thread updates the database. |
| 84 | mExecutor = Executors.newSingleThreadExecutor(); |
| 85 | } |
| 86 | if (mCurrentTask != null) { |
| 87 | // Cancel previous task. |
| 88 | mCurrentTask.cancel(true); |
| 89 | } |
Daichi Hirono | fda7474 | 2016-02-01 13:00:31 +0900 | [diff] [blame] | 90 | final UpdateRootsRunnable runnable = new UpdateRootsRunnable(); |
| 91 | mCurrentTask = new FutureTask<Void>(runnable, null); |
Daichi Hirono | e1d5771 | 2015-11-17 10:55:45 +0900 | [diff] [blame] | 92 | mExecutor.submit(mCurrentTask); |
Daichi Hirono | fda7474 | 2016-02-01 13:00:31 +0900 | [diff] [blame] | 93 | return runnable.mFirstScanCompleted; |
Daichi Hirono | e1d5771 | 2015-11-17 10:55:45 +0900 | [diff] [blame] | 94 | } |
| 95 | |
| 96 | /** |
| 97 | * Stops background thread and wait for its termination. |
| 98 | * @throws InterruptedException |
| 99 | */ |
| 100 | synchronized void pause() throws InterruptedException { |
| 101 | if (mExecutor == null) { |
Daichi Hirono | dc47344 | 2015-11-13 15:42:28 +0900 | [diff] [blame] | 102 | return; |
| 103 | } |
Daichi Hirono | e1d5771 | 2015-11-17 10:55:45 +0900 | [diff] [blame] | 104 | mExecutor.shutdownNow(); |
| 105 | if (!mExecutor.awaitTermination(AWAIT_TERMINATION_TIMEOUT, TimeUnit.MILLISECONDS)) { |
| 106 | Log.e(MtpDocumentsProvider.TAG, "Failed to terminate RootScanner's background thread."); |
Daichi Hirono | 8b9024f | 2015-08-12 12:59:09 +0900 | [diff] [blame] | 107 | } |
Daichi Hirono | e1d5771 | 2015-11-17 10:55:45 +0900 | [diff] [blame] | 108 | mExecutor = null; |
Daichi Hirono | 8b9024f | 2015-08-12 12:59:09 +0900 | [diff] [blame] | 109 | } |
| 110 | |
Daichi Hirono | e1d5771 | 2015-11-17 10:55:45 +0900 | [diff] [blame] | 111 | /** |
| 112 | * Runnable to scan roots and update the database information. |
| 113 | */ |
| 114 | private final class UpdateRootsRunnable implements Runnable { |
Daichi Hirono | fda7474 | 2016-02-01 13:00:31 +0900 | [diff] [blame] | 115 | final CountDownLatch mFirstScanCompleted = new CountDownLatch(1); |
| 116 | |
Daichi Hirono | 8b9024f | 2015-08-12 12:59:09 +0900 | [diff] [blame] | 117 | @Override |
| 118 | public void run() { |
| 119 | Process.setThreadPriority(Process.THREAD_PRIORITY_BACKGROUND); |
Daichi Hirono | e1d5771 | 2015-11-17 10:55:45 +0900 | [diff] [blame] | 120 | int pollingCount = 0; |
Daichi Hirono | 2bdb388 | 2015-12-22 12:57:47 +0900 | [diff] [blame] | 121 | while (true) { |
Daichi Hirono | e1d5771 | 2015-11-17 10:55:45 +0900 | [diff] [blame] | 122 | boolean changed = false; |
Daichi Hirono | b3fe72b | 2015-12-15 07:45:06 +0000 | [diff] [blame] | 123 | |
| 124 | // Update devices. |
Daichi Hirono | 20754c5 | 2015-12-15 18:52:26 +0900 | [diff] [blame] | 125 | final MtpDeviceRecord[] devices = mManager.getDevices(); |
Daichi Hirono | 619afda | 2016-02-07 14:23:43 +0900 | [diff] [blame] | 126 | try { |
| 127 | mDatabase.getMapper().startAddingDocuments(null /* parentDocumentId */); |
| 128 | for (final MtpDeviceRecord device : devices) { |
| 129 | if (mDatabase.getMapper().putDeviceDocument(device)) { |
| 130 | changed = true; |
| 131 | } |
| 132 | } |
| 133 | if (mDatabase.getMapper().stopAddingDocuments( |
| 134 | null /* parentDocumentId */)) { |
Daichi Hirono | 20754c5 | 2015-12-15 18:52:26 +0900 | [diff] [blame] | 135 | changed = true; |
Daichi Hirono | 8b9024f | 2015-08-12 12:59:09 +0900 | [diff] [blame] | 136 | } |
Daichi Hirono | 619afda | 2016-02-07 14:23:43 +0900 | [diff] [blame] | 137 | } catch (FileNotFoundException exception) { |
| 138 | // The top root (ID is null) must exist always. |
| 139 | // FileNotFoundException is unexpected. |
| 140 | Log.e(MtpDocumentsProvider.TAG, "Unexpected FileNotFoundException", exception); |
| 141 | throw new AssertionError("Unexpected exception for the top parent", exception); |
Daichi Hirono | 20754c5 | 2015-12-15 18:52:26 +0900 | [diff] [blame] | 142 | } |
Daichi Hirono | b3fe72b | 2015-12-15 07:45:06 +0000 | [diff] [blame] | 143 | |
| 144 | // Update roots. |
Daichi Hirono | 20754c5 | 2015-12-15 18:52:26 +0900 | [diff] [blame] | 145 | for (final MtpDeviceRecord device : devices) { |
| 146 | final String documentId = mDatabase.getDocumentIdForDevice(device.deviceId); |
| 147 | if (documentId == null) { |
| 148 | continue; |
| 149 | } |
Daichi Hirono | 619afda | 2016-02-07 14:23:43 +0900 | [diff] [blame] | 150 | try { |
| 151 | mDatabase.getMapper().startAddingDocuments(documentId); |
| 152 | if (mDatabase.getMapper().putStorageDocuments(documentId, device.roots)) { |
| 153 | changed = true; |
| 154 | } |
| 155 | if (mDatabase.getMapper().stopAddingDocuments(documentId)) { |
| 156 | changed = true; |
| 157 | } |
| 158 | } catch (FileNotFoundException exception) { |
| 159 | Log.e(MtpDocumentsProvider.TAG, "Parent document is gone.", exception); |
| 160 | continue; |
Daichi Hirono | b3fe72b | 2015-12-15 07:45:06 +0000 | [diff] [blame] | 161 | } |
Daichi Hirono | 7a375c4 | 2015-12-14 17:14:29 +0900 | [diff] [blame] | 162 | } |
Daichi Hirono | b3fe72b | 2015-12-15 07:45:06 +0000 | [diff] [blame] | 163 | |
Daichi Hirono | e1d5771 | 2015-11-17 10:55:45 +0900 | [diff] [blame] | 164 | if (changed) { |
| 165 | notifyChange(); |
| 166 | } |
Daichi Hirono | fda7474 | 2016-02-01 13:00:31 +0900 | [diff] [blame] | 167 | mFirstScanCompleted.countDown(); |
Daichi Hirono | e1d5771 | 2015-11-17 10:55:45 +0900 | [diff] [blame] | 168 | pollingCount++; |
| 169 | try { |
| 170 | // Use SHORT_POLLING_PERIOD for the first SHORT_POLLING_TIMES because it is |
| 171 | // more likely to add new root just after the device is added. |
| 172 | // TODO: Use short interval only for a device that is just added. |
| 173 | Thread.sleep(pollingCount > SHORT_POLLING_TIMES ? |
| 174 | LONG_POLLING_INTERVAL : SHORT_POLLING_INTERVAL); |
| 175 | } catch (InterruptedException exp) { |
Daichi Hirono | 2bdb388 | 2015-12-22 12:57:47 +0900 | [diff] [blame] | 176 | break; |
Daichi Hirono | e1d5771 | 2015-11-17 10:55:45 +0900 | [diff] [blame] | 177 | } |
Daichi Hirono | 8b9024f | 2015-08-12 12:59:09 +0900 | [diff] [blame] | 178 | } |
| 179 | } |
| 180 | } |
| 181 | } |