Arthur Ishiguro | 7a23a96 | 2017-11-01 10:52:28 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Copyright 2017 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 | |
| 17 | package com.android.server.location; |
| 18 | |
| 19 | import android.hardware.contexthub.V1_0.IContexthub; |
| 20 | import android.hardware.contexthub.V1_0.Result; |
| 21 | import android.hardware.contexthub.V1_0.TransactionResult; |
| 22 | import android.hardware.location.ContextHubTransaction; |
| 23 | import android.hardware.location.IContextHubTransactionCallback; |
| 24 | import android.hardware.location.NanoAppBinary; |
| 25 | import android.hardware.location.NanoAppState; |
| 26 | import android.os.RemoteException; |
| 27 | import android.util.Log; |
| 28 | |
| 29 | import java.util.ArrayDeque; |
| 30 | import java.util.Collections; |
| 31 | import java.util.List; |
| 32 | import java.util.concurrent.ScheduledThreadPoolExecutor; |
| 33 | import java.util.concurrent.ScheduledFuture; |
| 34 | import java.util.concurrent.TimeUnit; |
| 35 | import java.util.concurrent.atomic.AtomicInteger; |
| 36 | |
| 37 | /** |
| 38 | * Manages transactions at the Context Hub Service. |
| 39 | * |
| 40 | * This class maintains a queue of transaction requests made to the ContextHubService by clients, |
| 41 | * and executes them through the Context Hub. At any point in time, either the transaction queue is |
| 42 | * empty, or there is a pending transaction that is waiting for an asynchronous response from the |
| 43 | * hub. This class also handles synchronous errors and timeouts of each transaction. |
| 44 | * |
| 45 | * @hide |
| 46 | */ |
| 47 | /* package */ class ContextHubTransactionManager { |
| 48 | private static final String TAG = "ContextHubTransactionManager"; |
| 49 | |
| 50 | /* |
| 51 | * Maximum number of transaction requests that can be pending at a time |
| 52 | */ |
| 53 | private static final int MAX_PENDING_REQUESTS = 10; |
| 54 | |
| 55 | /* |
| 56 | * The proxy to talk to the Context Hub |
| 57 | */ |
| 58 | private final IContexthub mContextHubProxy; |
| 59 | |
| 60 | /* |
Arthur Ishiguro | 0069f12 | 2017-11-20 15:07:14 -0800 | [diff] [blame] | 61 | * The manager for all clients for the service. |
| 62 | */ |
| 63 | private final ContextHubClientManager mClientManager; |
| 64 | |
| 65 | /* |
Arthur Ishiguro | 7a23a96 | 2017-11-01 10:52:28 -0700 | [diff] [blame] | 66 | * A queue containing the current transactions |
| 67 | */ |
| 68 | private final ArrayDeque<ContextHubServiceTransaction> mTransactionQueue = new ArrayDeque<>(); |
| 69 | |
| 70 | /* |
| 71 | * The next available transaction ID |
| 72 | */ |
| 73 | private final AtomicInteger mNextAvailableId = new AtomicInteger(); |
| 74 | |
| 75 | /* |
| 76 | * An executor and the future object for scheduling timeout timers |
| 77 | */ |
| 78 | private final ScheduledThreadPoolExecutor mTimeoutExecutor = new ScheduledThreadPoolExecutor(1); |
| 79 | private ScheduledFuture<?> mTimeoutFuture = null; |
| 80 | |
Arthur Ishiguro | 0069f12 | 2017-11-20 15:07:14 -0800 | [diff] [blame] | 81 | /* package */ ContextHubTransactionManager( |
| 82 | IContexthub contextHubProxy, ContextHubClientManager clientManager) { |
Arthur Ishiguro | 7a23a96 | 2017-11-01 10:52:28 -0700 | [diff] [blame] | 83 | mContextHubProxy = contextHubProxy; |
Arthur Ishiguro | 0069f12 | 2017-11-20 15:07:14 -0800 | [diff] [blame] | 84 | mClientManager = clientManager; |
Arthur Ishiguro | 7a23a96 | 2017-11-01 10:52:28 -0700 | [diff] [blame] | 85 | } |
| 86 | |
| 87 | /** |
| 88 | * Creates a transaction for loading a nanoapp. |
| 89 | * |
| 90 | * @param contextHubId the ID of the hub to load the nanoapp to |
| 91 | * @param nanoAppBinary the binary of the nanoapp to load |
| 92 | * @param onCompleteCallback the client on complete callback |
| 93 | * @return the generated transaction |
| 94 | */ |
| 95 | /* package */ ContextHubServiceTransaction createLoadTransaction( |
| 96 | int contextHubId, NanoAppBinary nanoAppBinary, |
| 97 | IContextHubTransactionCallback onCompleteCallback) { |
| 98 | return new ContextHubServiceTransaction( |
| 99 | mNextAvailableId.getAndIncrement(), ContextHubTransaction.TYPE_LOAD_NANOAPP) { |
| 100 | @Override |
| 101 | /* package */ int onTransact() { |
| 102 | android.hardware.contexthub.V1_0.NanoAppBinary hidlNanoAppBinary = |
| 103 | ContextHubServiceUtil.createHidlNanoAppBinary(nanoAppBinary); |
| 104 | try { |
| 105 | return mContextHubProxy.loadNanoApp( |
| 106 | contextHubId, hidlNanoAppBinary, this.getTransactionId()); |
| 107 | } catch (RemoteException e) { |
| 108 | Log.e(TAG, "RemoteException while trying to load nanoapp with ID 0x" + |
| 109 | Long.toHexString(nanoAppBinary.getNanoAppId())); |
| 110 | return Result.UNKNOWN_FAILURE; |
| 111 | } |
| 112 | } |
| 113 | |
| 114 | @Override |
| 115 | /* package */ void onTimeout() { |
| 116 | onTransactionComplete(ContextHubTransaction.TRANSACTION_FAILED_TIMEOUT); |
| 117 | } |
| 118 | |
| 119 | @Override |
| 120 | /* package */ void onTransactionComplete(int result) { |
| 121 | try { |
| 122 | onCompleteCallback.onTransactionComplete(result); |
Arthur Ishiguro | 0069f12 | 2017-11-20 15:07:14 -0800 | [diff] [blame] | 123 | if (result == Result.OK) { |
| 124 | mClientManager.onNanoAppLoaded(contextHubId, nanoAppBinary.getNanoAppId()); |
| 125 | } |
Arthur Ishiguro | 7a23a96 | 2017-11-01 10:52:28 -0700 | [diff] [blame] | 126 | } catch (RemoteException e) { |
| 127 | Log.e(TAG, "RemoteException while calling client onTransactionComplete"); |
| 128 | } |
| 129 | } |
| 130 | }; |
| 131 | } |
| 132 | |
| 133 | /** |
| 134 | * Creates a transaction for unloading a nanoapp. |
| 135 | * |
| 136 | * @param contextHubId the ID of the hub to load the nanoapp to |
| 137 | * @param nanoAppId the ID of the nanoapp to unload |
| 138 | * @param onCompleteCallback the client on complete callback |
| 139 | * @return the generated transaction |
| 140 | */ |
| 141 | /* package */ ContextHubServiceTransaction createUnloadTransaction( |
| 142 | int contextHubId, long nanoAppId, IContextHubTransactionCallback onCompleteCallback) { |
| 143 | return new ContextHubServiceTransaction( |
| 144 | mNextAvailableId.getAndIncrement(), ContextHubTransaction.TYPE_UNLOAD_NANOAPP) { |
| 145 | @Override |
| 146 | /* package */ int onTransact() { |
| 147 | try { |
| 148 | return mContextHubProxy.unloadNanoApp( |
| 149 | contextHubId, nanoAppId, this.getTransactionId()); |
| 150 | } catch (RemoteException e) { |
| 151 | Log.e(TAG, "RemoteException while trying to unload nanoapp with ID 0x" + |
| 152 | Long.toHexString(nanoAppId)); |
| 153 | return Result.UNKNOWN_FAILURE; |
| 154 | } |
| 155 | } |
| 156 | |
| 157 | @Override |
| 158 | /* package */ void onTimeout() { |
| 159 | onTransactionComplete(ContextHubTransaction.TRANSACTION_FAILED_TIMEOUT); |
| 160 | } |
| 161 | |
| 162 | @Override |
| 163 | /* package */ void onTransactionComplete(int result) { |
| 164 | try { |
| 165 | onCompleteCallback.onTransactionComplete(result); |
Arthur Ishiguro | 0069f12 | 2017-11-20 15:07:14 -0800 | [diff] [blame] | 166 | if (result == Result.OK) { |
| 167 | mClientManager.onNanoAppUnloaded(contextHubId, nanoAppId); |
| 168 | } |
Arthur Ishiguro | 7a23a96 | 2017-11-01 10:52:28 -0700 | [diff] [blame] | 169 | } catch (RemoteException e) { |
| 170 | Log.e(TAG, "RemoteException while calling client onTransactionComplete"); |
| 171 | } |
| 172 | } |
| 173 | }; |
| 174 | } |
| 175 | |
| 176 | /** |
| 177 | * Creates a transaction for querying for a list of nanoapps. |
| 178 | * |
| 179 | * @param contextHubId the ID of the hub to query |
| 180 | * @param onCompleteCallback the client on complete callback |
| 181 | * @return the generated transaction |
| 182 | */ |
| 183 | /* package */ ContextHubServiceTransaction createQueryTransaction( |
| 184 | int contextHubId, IContextHubTransactionCallback onCompleteCallback) { |
| 185 | return new ContextHubServiceTransaction( |
| 186 | mNextAvailableId.getAndIncrement(), ContextHubTransaction.TYPE_QUERY_NANOAPPS) { |
| 187 | @Override |
| 188 | /* package */ int onTransact() { |
| 189 | try { |
| 190 | return mContextHubProxy.queryApps(contextHubId); |
| 191 | } catch (RemoteException e) { |
| 192 | Log.e(TAG, "RemoteException while trying to query for nanoapps"); |
| 193 | return Result.UNKNOWN_FAILURE; |
| 194 | } |
| 195 | } |
| 196 | |
| 197 | @Override |
| 198 | /* package */ void onTimeout() { |
| 199 | onQueryResponse(ContextHubTransaction.TRANSACTION_FAILED_TIMEOUT, |
| 200 | Collections.emptyList()); |
| 201 | } |
| 202 | |
| 203 | @Override |
| 204 | /* package */ void onQueryResponse(int result, List<NanoAppState> nanoAppStateList) { |
| 205 | try { |
| 206 | onCompleteCallback.onQueryResponse(result, nanoAppStateList); |
| 207 | } catch (RemoteException e) { |
| 208 | Log.e(TAG, "RemoteException while calling client onQueryComplete"); |
| 209 | } |
| 210 | } |
| 211 | }; |
| 212 | } |
| 213 | |
| 214 | /** |
| 215 | * Adds a new transaction to the queue. |
| 216 | * |
| 217 | * If there was no pending transaction at the time, the transaction that was added will be |
| 218 | * started in this method. |
| 219 | * |
| 220 | * @param transaction the transaction to add |
| 221 | * @throws IllegalStateException if the queue is full |
| 222 | */ |
| 223 | /* package */ |
| 224 | synchronized void addTransaction( |
| 225 | ContextHubServiceTransaction transaction) throws IllegalStateException { |
| 226 | if (mTransactionQueue.size() == MAX_PENDING_REQUESTS) { |
| 227 | throw new IllegalStateException("Transaction transaction queue is full (capacity = " |
| 228 | + MAX_PENDING_REQUESTS + ")"); |
| 229 | } |
| 230 | mTransactionQueue.add(transaction); |
| 231 | |
| 232 | if (mTransactionQueue.size() == 1) { |
| 233 | startNextTransaction(); |
| 234 | } |
| 235 | } |
| 236 | |
| 237 | /** |
| 238 | * Handles a transaction response from a Context Hub. |
| 239 | * |
| 240 | * @param transactionId the transaction ID of the response |
| 241 | * @param result the result of the transaction |
| 242 | */ |
| 243 | /* package */ |
| 244 | synchronized void onTransactionResponse(int transactionId, int result) { |
| 245 | ContextHubServiceTransaction transaction = mTransactionQueue.peek(); |
| 246 | if (transaction == null) { |
| 247 | Log.w(TAG, "Received unexpected transaction response (no transaction pending)"); |
| 248 | return; |
| 249 | } |
| 250 | if (transaction.getTransactionId() != transactionId) { |
| 251 | Log.w(TAG, "Received unexpected transaction response (expected ID = " |
| 252 | + transaction.getTransactionId() + ", received ID = " + transactionId + ")"); |
| 253 | return; |
| 254 | } |
| 255 | |
| 256 | transaction.onTransactionComplete(result); |
| 257 | removeTransactionAndStartNext(); |
| 258 | } |
| 259 | |
| 260 | /** |
| 261 | * Handles a query response from a Context Hub. |
| 262 | * |
| 263 | * @param nanoAppStateList the list of nanoapps included in the response |
| 264 | */ |
| 265 | /* package */ |
| 266 | synchronized void onQueryResponse(List<NanoAppState> nanoAppStateList) { |
| 267 | ContextHubServiceTransaction transaction = mTransactionQueue.peek(); |
| 268 | if (transaction == null) { |
| 269 | Log.w(TAG, "Received unexpected query response (no transaction pending)"); |
| 270 | return; |
| 271 | } |
| 272 | if (transaction.getTransactionType() != ContextHubTransaction.TYPE_QUERY_NANOAPPS) { |
| 273 | Log.w(TAG, "Received unexpected query response (expected " + transaction + ")"); |
| 274 | return; |
| 275 | } |
| 276 | |
| 277 | transaction.onQueryResponse(TransactionResult.SUCCESS, nanoAppStateList); |
| 278 | removeTransactionAndStartNext(); |
| 279 | } |
| 280 | |
| 281 | /** |
| 282 | * Handles a hub reset event by stopping a pending transaction and starting the next. |
| 283 | */ |
| 284 | /* package */ |
| 285 | synchronized void onHubReset() { |
| 286 | ContextHubServiceTransaction transaction = mTransactionQueue.peek(); |
| 287 | if (transaction == null) { |
| 288 | return; |
| 289 | } |
| 290 | |
| 291 | removeTransactionAndStartNext(); |
| 292 | } |
| 293 | |
| 294 | /** |
| 295 | * Pops the front transaction from the queue and starts the next pending transaction request. |
| 296 | * |
| 297 | * Removing elements from the transaction queue must only be done through this method. When a |
| 298 | * pending transaction is removed, the timeout timer is cancelled and the transaction is marked |
| 299 | * complete. |
| 300 | * |
| 301 | * It is assumed that the transaction queue is non-empty when this method is invoked, and that |
| 302 | * the caller has obtained a lock on this ContextHubTransactionManager object. |
| 303 | */ |
| 304 | private void removeTransactionAndStartNext() { |
| 305 | mTimeoutFuture.cancel(false /* mayInterruptIfRunning */); |
| 306 | |
| 307 | ContextHubServiceTransaction transaction = mTransactionQueue.remove(); |
| 308 | transaction.setComplete(); |
| 309 | |
| 310 | if (!mTransactionQueue.isEmpty()) { |
| 311 | startNextTransaction(); |
| 312 | } |
| 313 | } |
| 314 | |
| 315 | /** |
| 316 | * Starts the next pending transaction request. |
| 317 | * |
| 318 | * Starting new transactions must only be done through this method. This method continues to |
| 319 | * process the transaction queue as long as there are pending requests, and no transaction is |
| 320 | * pending. |
| 321 | * |
| 322 | * It is assumed that the caller has obtained a lock on this ContextHubTransactionManager |
| 323 | * object. |
| 324 | */ |
| 325 | private void startNextTransaction() { |
| 326 | int result = Result.UNKNOWN_FAILURE; |
| 327 | while (result != Result.OK && !mTransactionQueue.isEmpty()) { |
| 328 | ContextHubServiceTransaction transaction = mTransactionQueue.peek(); |
| 329 | result = transaction.onTransact(); |
| 330 | |
| 331 | if (result == Result.OK) { |
| 332 | Runnable onTimeoutFunc = () -> { |
| 333 | synchronized (this) { |
| 334 | if (!transaction.isComplete()) { |
| 335 | Log.d(TAG, transaction + " timed out"); |
| 336 | transaction.onTimeout(); |
| 337 | |
| 338 | removeTransactionAndStartNext(); |
| 339 | } |
| 340 | } |
| 341 | }; |
| 342 | |
| 343 | long timeoutSeconds = transaction.getTimeout(TimeUnit.SECONDS); |
| 344 | mTimeoutFuture = mTimeoutExecutor.schedule(onTimeoutFunc, timeoutSeconds, |
| 345 | TimeUnit.SECONDS); |
| 346 | } else { |
| 347 | mTransactionQueue.remove(); |
| 348 | } |
| 349 | } |
| 350 | } |
| 351 | } |