Jeff Brown | e5360fb | 2011-10-31 17:48:13 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2011 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 android.database.sqlite; |
| 18 | |
| 19 | import dalvik.system.CloseGuard; |
| 20 | |
Jeff Brown | 4c1241d | 2012-02-02 17:05:00 -0800 | [diff] [blame] | 21 | import android.content.CancellationSignal; |
Jeff Brown | 75ea64f | 2012-01-25 19:37:13 -0800 | [diff] [blame] | 22 | import android.content.OperationCanceledException; |
Jeff Brown | e5360fb | 2011-10-31 17:48:13 -0700 | [diff] [blame] | 23 | import android.database.sqlite.SQLiteDebug.DbStats; |
| 24 | import android.os.SystemClock; |
| 25 | import android.util.Log; |
| 26 | import android.util.PrefixPrinter; |
| 27 | import android.util.Printer; |
| 28 | |
| 29 | import java.io.Closeable; |
| 30 | import java.util.ArrayList; |
| 31 | import java.util.Map; |
| 32 | import java.util.WeakHashMap; |
| 33 | import java.util.concurrent.atomic.AtomicBoolean; |
| 34 | import java.util.concurrent.locks.LockSupport; |
| 35 | |
| 36 | /** |
| 37 | * Maintains a pool of active SQLite database connections. |
| 38 | * <p> |
| 39 | * At any given time, a connection is either owned by the pool, or it has been |
| 40 | * acquired by a {@link SQLiteSession}. When the {@link SQLiteSession} is |
| 41 | * finished with the connection it is using, it must return the connection |
| 42 | * back to the pool. |
| 43 | * </p><p> |
| 44 | * The pool holds strong references to the connections it owns. However, |
| 45 | * it only holds <em>weak references</em> to the connections that sessions |
| 46 | * have acquired from it. Using weak references in the latter case ensures |
| 47 | * that the connection pool can detect when connections have been improperly |
| 48 | * abandoned so that it can create new connections to replace them if needed. |
| 49 | * </p><p> |
| 50 | * The connection pool is thread-safe (but the connections themselves are not). |
| 51 | * </p> |
| 52 | * |
| 53 | * <h2>Exception safety</h2> |
| 54 | * <p> |
| 55 | * This code attempts to maintain the invariant that opened connections are |
| 56 | * always owned. Unfortunately that means it needs to handle exceptions |
| 57 | * all over to ensure that broken connections get cleaned up. Most |
| 58 | * operations invokving SQLite can throw {@link SQLiteException} or other |
| 59 | * runtime exceptions. This is a bit of a pain to deal with because the compiler |
| 60 | * cannot help us catch missing exception handling code. |
| 61 | * </p><p> |
| 62 | * The general rule for this file: If we are making calls out to |
| 63 | * {@link SQLiteConnection} then we must be prepared to handle any |
| 64 | * runtime exceptions it might throw at us. Note that out-of-memory |
| 65 | * is an {@link Error}, not a {@link RuntimeException}. We don't trouble ourselves |
| 66 | * handling out of memory because it is hard to do anything at all sensible then |
| 67 | * and most likely the VM is about to crash. |
| 68 | * </p> |
| 69 | * |
| 70 | * @hide |
| 71 | */ |
| 72 | public final class SQLiteConnectionPool implements Closeable { |
| 73 | private static final String TAG = "SQLiteConnectionPool"; |
| 74 | |
| 75 | // Amount of time to wait in milliseconds before unblocking acquireConnection |
| 76 | // and logging a message about the connection pool being busy. |
| 77 | private static final long CONNECTION_POOL_BUSY_MILLIS = 30 * 1000; // 30 seconds |
| 78 | |
| 79 | private final CloseGuard mCloseGuard = CloseGuard.get(); |
| 80 | |
| 81 | private final Object mLock = new Object(); |
| 82 | private final AtomicBoolean mConnectionLeaked = new AtomicBoolean(); |
| 83 | private final SQLiteDatabaseConfiguration mConfiguration; |
| 84 | private boolean mIsOpen; |
| 85 | private int mNextConnectionId; |
| 86 | |
| 87 | private ConnectionWaiter mConnectionWaiterPool; |
| 88 | private ConnectionWaiter mConnectionWaiterQueue; |
| 89 | |
| 90 | // Strong references to all available connections. |
| 91 | private final ArrayList<SQLiteConnection> mAvailableNonPrimaryConnections = |
| 92 | new ArrayList<SQLiteConnection>(); |
| 93 | private SQLiteConnection mAvailablePrimaryConnection; |
| 94 | |
Jeff Brown | 559d064 | 2012-02-29 10:19:12 -0800 | [diff] [blame] | 95 | // Describes what should happen to an acquired connection when it is returned to the pool. |
| 96 | enum AcquiredConnectionStatus { |
| 97 | // The connection should be returned to the pool as usual. |
| 98 | NORMAL, |
| 99 | |
| 100 | // The connection must be reconfigured before being returned. |
| 101 | RECONFIGURE, |
| 102 | |
| 103 | // The connection must be closed and discarded. |
| 104 | DISCARD, |
| 105 | } |
| 106 | |
Jeff Brown | e5360fb | 2011-10-31 17:48:13 -0700 | [diff] [blame] | 107 | // Weak references to all acquired connections. The associated value |
Jeff Brown | 559d064 | 2012-02-29 10:19:12 -0800 | [diff] [blame] | 108 | // indicates whether the connection must be reconfigured before being |
| 109 | // returned to the available connection list or discarded. |
Jeff Brown | e5360fb | 2011-10-31 17:48:13 -0700 | [diff] [blame] | 110 | // For example, the prepared statement cache size may have changed and |
Jeff Brown | 559d064 | 2012-02-29 10:19:12 -0800 | [diff] [blame] | 111 | // need to be updated in preparation for the next client. |
| 112 | private final WeakHashMap<SQLiteConnection, AcquiredConnectionStatus> mAcquiredConnections = |
| 113 | new WeakHashMap<SQLiteConnection, AcquiredConnectionStatus>(); |
Jeff Brown | e5360fb | 2011-10-31 17:48:13 -0700 | [diff] [blame] | 114 | |
| 115 | /** |
| 116 | * Connection flag: Read-only. |
| 117 | * <p> |
| 118 | * This flag indicates that the connection will only be used to |
| 119 | * perform read-only operations. |
| 120 | * </p> |
| 121 | */ |
| 122 | public static final int CONNECTION_FLAG_READ_ONLY = 1 << 0; |
| 123 | |
| 124 | /** |
| 125 | * Connection flag: Primary connection affinity. |
| 126 | * <p> |
| 127 | * This flag indicates that the primary connection is required. |
| 128 | * This flag helps support legacy applications that expect most data modifying |
| 129 | * operations to be serialized by locking the primary database connection. |
| 130 | * Setting this flag essentially implements the old "db lock" concept by preventing |
| 131 | * an operation from being performed until it can obtain exclusive access to |
| 132 | * the primary connection. |
| 133 | * </p> |
| 134 | */ |
| 135 | public static final int CONNECTION_FLAG_PRIMARY_CONNECTION_AFFINITY = 1 << 1; |
| 136 | |
| 137 | /** |
| 138 | * Connection flag: Connection is being used interactively. |
| 139 | * <p> |
| 140 | * This flag indicates that the connection is needed by the UI thread. |
| 141 | * The connection pool can use this flag to elevate the priority |
| 142 | * of the database connection request. |
| 143 | * </p> |
| 144 | */ |
| 145 | public static final int CONNECTION_FLAG_INTERACTIVE = 1 << 2; |
| 146 | |
| 147 | private SQLiteConnectionPool(SQLiteDatabaseConfiguration configuration) { |
| 148 | mConfiguration = new SQLiteDatabaseConfiguration(configuration); |
| 149 | } |
| 150 | |
| 151 | @Override |
| 152 | protected void finalize() throws Throwable { |
| 153 | try { |
| 154 | dispose(true); |
| 155 | } finally { |
| 156 | super.finalize(); |
| 157 | } |
| 158 | } |
| 159 | |
| 160 | /** |
| 161 | * Opens a connection pool for the specified database. |
| 162 | * |
| 163 | * @param configuration The database configuration. |
| 164 | * @return The connection pool. |
| 165 | * |
| 166 | * @throws SQLiteException if a database error occurs. |
| 167 | */ |
| 168 | public static SQLiteConnectionPool open(SQLiteDatabaseConfiguration configuration) { |
| 169 | if (configuration == null) { |
| 170 | throw new IllegalArgumentException("configuration must not be null."); |
| 171 | } |
| 172 | |
| 173 | // Create the pool. |
| 174 | SQLiteConnectionPool pool = new SQLiteConnectionPool(configuration); |
| 175 | pool.open(); // might throw |
| 176 | return pool; |
| 177 | } |
| 178 | |
| 179 | // Might throw |
| 180 | private void open() { |
| 181 | // Open the primary connection. |
| 182 | // This might throw if the database is corrupt. |
Jeff Brown | 559d064 | 2012-02-29 10:19:12 -0800 | [diff] [blame] | 183 | mAvailablePrimaryConnection = openConnectionLocked(mConfiguration, |
Jeff Brown | e5360fb | 2011-10-31 17:48:13 -0700 | [diff] [blame] | 184 | true /*primaryConnection*/); // might throw |
| 185 | |
| 186 | // Mark the pool as being open for business. |
| 187 | mIsOpen = true; |
| 188 | mCloseGuard.open("close"); |
| 189 | } |
| 190 | |
| 191 | /** |
| 192 | * Closes the connection pool. |
| 193 | * <p> |
| 194 | * When the connection pool is closed, it will refuse all further requests |
| 195 | * to acquire connections. All connections that are currently available in |
| 196 | * the pool are closed immediately. Any connections that are still in use |
| 197 | * will be closed as soon as they are returned to the pool. |
| 198 | * </p> |
| 199 | * |
| 200 | * @throws IllegalStateException if the pool has been closed. |
| 201 | */ |
| 202 | public void close() { |
| 203 | dispose(false); |
| 204 | } |
| 205 | |
| 206 | private void dispose(boolean finalized) { |
| 207 | if (mCloseGuard != null) { |
| 208 | if (finalized) { |
| 209 | mCloseGuard.warnIfOpen(); |
| 210 | } |
| 211 | mCloseGuard.close(); |
| 212 | } |
| 213 | |
| 214 | if (!finalized) { |
| 215 | // Close all connections. We don't need (or want) to do this |
| 216 | // when finalized because we don't know what state the connections |
| 217 | // themselves will be in. The finalizer is really just here for CloseGuard. |
| 218 | // The connections will take care of themselves when their own finalizers run. |
| 219 | synchronized (mLock) { |
| 220 | throwIfClosedLocked(); |
| 221 | |
| 222 | mIsOpen = false; |
| 223 | |
Jeff Brown | 559d064 | 2012-02-29 10:19:12 -0800 | [diff] [blame] | 224 | closeAvailableConnectionsAndLogExceptionsLocked(); |
Jeff Brown | e5360fb | 2011-10-31 17:48:13 -0700 | [diff] [blame] | 225 | |
| 226 | final int pendingCount = mAcquiredConnections.size(); |
| 227 | if (pendingCount != 0) { |
| 228 | Log.i(TAG, "The connection pool for " + mConfiguration.label |
| 229 | + " has been closed but there are still " |
| 230 | + pendingCount + " connections in use. They will be closed " |
| 231 | + "as they are released back to the pool."); |
| 232 | } |
| 233 | |
| 234 | wakeConnectionWaitersLocked(); |
| 235 | } |
| 236 | } |
| 237 | } |
| 238 | |
| 239 | /** |
| 240 | * Reconfigures the database configuration of the connection pool and all of its |
| 241 | * connections. |
| 242 | * <p> |
| 243 | * Configuration changes are propagated down to connections immediately if |
| 244 | * they are available or as soon as they are released. This includes changes |
| 245 | * that affect the size of the pool. |
| 246 | * </p> |
| 247 | * |
| 248 | * @param configuration The new configuration. |
| 249 | * |
| 250 | * @throws IllegalStateException if the pool has been closed. |
| 251 | */ |
| 252 | public void reconfigure(SQLiteDatabaseConfiguration configuration) { |
| 253 | if (configuration == null) { |
| 254 | throw new IllegalArgumentException("configuration must not be null."); |
| 255 | } |
| 256 | |
| 257 | synchronized (mLock) { |
| 258 | throwIfClosedLocked(); |
| 259 | |
Jeff Brown | e67ca42 | 2012-03-21 17:24:05 -0700 | [diff] [blame] | 260 | boolean restrictToOneConnection = false; |
Jeff Brown | d67c8c6 | 2012-03-22 14:15:01 -0700 | [diff] [blame] | 261 | if (mConfiguration.walEnabled != configuration.walEnabled) { |
Jeff Brown | e67ca42 | 2012-03-21 17:24:05 -0700 | [diff] [blame] | 262 | // WAL mode can only be changed if there are no acquired connections |
| 263 | // because we need to close all but the primary connection first. |
| 264 | if (!mAcquiredConnections.isEmpty()) { |
| 265 | throw new IllegalStateException("Write Ahead Logging (WAL) mode cannot " |
| 266 | + "be enabled or disabled while there are transactions in " |
| 267 | + "progress. Finish all transactions and release all active " |
| 268 | + "database connections first."); |
| 269 | } |
| 270 | |
| 271 | // Close all non-primary connections. This should happen immediately |
| 272 | // because none of them are in use. |
| 273 | closeAvailableNonPrimaryConnectionsAndLogExceptionsLocked(); |
| 274 | assert mAvailableNonPrimaryConnections.isEmpty(); |
| 275 | |
| 276 | restrictToOneConnection = true; |
| 277 | } |
| 278 | |
Jeff Brown | 559d064 | 2012-02-29 10:19:12 -0800 | [diff] [blame] | 279 | if (mConfiguration.openFlags != configuration.openFlags) { |
Jeff Brown | e67ca42 | 2012-03-21 17:24:05 -0700 | [diff] [blame] | 280 | // If we are changing open flags and WAL mode at the same time, then |
| 281 | // we have no choice but to close the primary connection beforehand |
| 282 | // because there can only be one connection open when we change WAL mode. |
| 283 | if (restrictToOneConnection) { |
| 284 | closeAvailableConnectionsAndLogExceptionsLocked(); |
| 285 | } |
| 286 | |
Jeff Brown | 559d064 | 2012-02-29 10:19:12 -0800 | [diff] [blame] | 287 | // Try to reopen the primary connection using the new open flags then |
| 288 | // close and discard all existing connections. |
| 289 | // This might throw if the database is corrupt or cannot be opened in |
| 290 | // the new mode in which case existing connections will remain untouched. |
| 291 | SQLiteConnection newPrimaryConnection = openConnectionLocked(configuration, |
| 292 | true /*primaryConnection*/); // might throw |
Jeff Brown | e5360fb | 2011-10-31 17:48:13 -0700 | [diff] [blame] | 293 | |
Jeff Brown | 559d064 | 2012-02-29 10:19:12 -0800 | [diff] [blame] | 294 | closeAvailableConnectionsAndLogExceptionsLocked(); |
| 295 | discardAcquiredConnectionsLocked(); |
| 296 | |
| 297 | mAvailablePrimaryConnection = newPrimaryConnection; |
| 298 | mConfiguration.updateParametersFrom(configuration); |
| 299 | } else { |
| 300 | // Reconfigure the database connections in place. |
| 301 | mConfiguration.updateParametersFrom(configuration); |
| 302 | |
| 303 | closeExcessConnectionsAndLogExceptionsLocked(); |
| 304 | reconfigureAllConnectionsLocked(); |
Jeff Brown | e5360fb | 2011-10-31 17:48:13 -0700 | [diff] [blame] | 305 | } |
| 306 | |
Jeff Brown | e5360fb | 2011-10-31 17:48:13 -0700 | [diff] [blame] | 307 | wakeConnectionWaitersLocked(); |
| 308 | } |
| 309 | } |
| 310 | |
| 311 | /** |
| 312 | * Acquires a connection from the pool. |
| 313 | * <p> |
| 314 | * The caller must call {@link #releaseConnection} to release the connection |
| 315 | * back to the pool when it is finished. Failure to do so will result |
| 316 | * in much unpleasantness. |
| 317 | * </p> |
| 318 | * |
| 319 | * @param sql If not null, try to find a connection that already has |
| 320 | * the specified SQL statement in its prepared statement cache. |
| 321 | * @param connectionFlags The connection request flags. |
Jeff Brown | 4c1241d | 2012-02-02 17:05:00 -0800 | [diff] [blame] | 322 | * @param cancellationSignal A signal to cancel the operation in progress, or null if none. |
Jeff Brown | e5360fb | 2011-10-31 17:48:13 -0700 | [diff] [blame] | 323 | * @return The connection that was acquired, never null. |
| 324 | * |
| 325 | * @throws IllegalStateException if the pool has been closed. |
| 326 | * @throws SQLiteException if a database error occurs. |
Jeff Brown | 75ea64f | 2012-01-25 19:37:13 -0800 | [diff] [blame] | 327 | * @throws OperationCanceledException if the operation was canceled. |
Jeff Brown | e5360fb | 2011-10-31 17:48:13 -0700 | [diff] [blame] | 328 | */ |
Jeff Brown | 75ea64f | 2012-01-25 19:37:13 -0800 | [diff] [blame] | 329 | public SQLiteConnection acquireConnection(String sql, int connectionFlags, |
Jeff Brown | 4c1241d | 2012-02-02 17:05:00 -0800 | [diff] [blame] | 330 | CancellationSignal cancellationSignal) { |
| 331 | return waitForConnection(sql, connectionFlags, cancellationSignal); |
Jeff Brown | e5360fb | 2011-10-31 17:48:13 -0700 | [diff] [blame] | 332 | } |
| 333 | |
| 334 | /** |
| 335 | * Releases a connection back to the pool. |
| 336 | * <p> |
| 337 | * It is ok to call this method after the pool has closed, to release |
| 338 | * connections that were still in use at the time of closure. |
| 339 | * </p> |
| 340 | * |
| 341 | * @param connection The connection to release. Must not be null. |
| 342 | * |
| 343 | * @throws IllegalStateException if the connection was not acquired |
| 344 | * from this pool or if it has already been released. |
| 345 | */ |
| 346 | public void releaseConnection(SQLiteConnection connection) { |
| 347 | synchronized (mLock) { |
Jeff Brown | 559d064 | 2012-02-29 10:19:12 -0800 | [diff] [blame] | 348 | AcquiredConnectionStatus status = mAcquiredConnections.remove(connection); |
| 349 | if (status == null) { |
Jeff Brown | e5360fb | 2011-10-31 17:48:13 -0700 | [diff] [blame] | 350 | throw new IllegalStateException("Cannot perform this operation " |
| 351 | + "because the specified connection was not acquired " |
| 352 | + "from this pool or has already been released."); |
| 353 | } |
| 354 | |
| 355 | if (!mIsOpen) { |
| 356 | closeConnectionAndLogExceptionsLocked(connection); |
| 357 | } else if (connection.isPrimaryConnection()) { |
Jeff Brown | 559d064 | 2012-02-29 10:19:12 -0800 | [diff] [blame] | 358 | if (recycleConnectionLocked(connection, status)) { |
| 359 | assert mAvailablePrimaryConnection == null; |
Jeff Brown | e5360fb | 2011-10-31 17:48:13 -0700 | [diff] [blame] | 360 | mAvailablePrimaryConnection = connection; |
| 361 | } |
| 362 | wakeConnectionWaitersLocked(); |
| 363 | } else if (mAvailableNonPrimaryConnections.size() >= |
| 364 | mConfiguration.maxConnectionPoolSize - 1) { |
| 365 | closeConnectionAndLogExceptionsLocked(connection); |
| 366 | } else { |
Jeff Brown | 559d064 | 2012-02-29 10:19:12 -0800 | [diff] [blame] | 367 | if (recycleConnectionLocked(connection, status)) { |
Jeff Brown | e5360fb | 2011-10-31 17:48:13 -0700 | [diff] [blame] | 368 | mAvailableNonPrimaryConnections.add(connection); |
| 369 | } |
| 370 | wakeConnectionWaitersLocked(); |
| 371 | } |
| 372 | } |
| 373 | } |
| 374 | |
Jeff Brown | 559d064 | 2012-02-29 10:19:12 -0800 | [diff] [blame] | 375 | // Can't throw. |
| 376 | private boolean recycleConnectionLocked(SQLiteConnection connection, |
| 377 | AcquiredConnectionStatus status) { |
| 378 | if (status == AcquiredConnectionStatus.RECONFIGURE) { |
| 379 | try { |
| 380 | connection.reconfigure(mConfiguration); // might throw |
| 381 | } catch (RuntimeException ex) { |
| 382 | Log.e(TAG, "Failed to reconfigure released connection, closing it: " |
| 383 | + connection, ex); |
| 384 | status = AcquiredConnectionStatus.DISCARD; |
| 385 | } |
| 386 | } |
| 387 | if (status == AcquiredConnectionStatus.DISCARD) { |
| 388 | closeConnectionAndLogExceptionsLocked(connection); |
| 389 | return false; |
| 390 | } |
| 391 | return true; |
| 392 | } |
| 393 | |
Jeff Brown | e5360fb | 2011-10-31 17:48:13 -0700 | [diff] [blame] | 394 | /** |
| 395 | * Returns true if the session should yield the connection due to |
| 396 | * contention over available database connections. |
| 397 | * |
| 398 | * @param connection The connection owned by the session. |
| 399 | * @param connectionFlags The connection request flags. |
| 400 | * @return True if the session should yield its connection. |
| 401 | * |
| 402 | * @throws IllegalStateException if the connection was not acquired |
| 403 | * from this pool or if it has already been released. |
| 404 | */ |
| 405 | public boolean shouldYieldConnection(SQLiteConnection connection, int connectionFlags) { |
| 406 | synchronized (mLock) { |
| 407 | if (!mAcquiredConnections.containsKey(connection)) { |
| 408 | throw new IllegalStateException("Cannot perform this operation " |
| 409 | + "because the specified connection was not acquired " |
| 410 | + "from this pool or has already been released."); |
| 411 | } |
| 412 | |
| 413 | if (!mIsOpen) { |
| 414 | return false; |
| 415 | } |
| 416 | |
| 417 | return isSessionBlockingImportantConnectionWaitersLocked( |
| 418 | connection.isPrimaryConnection(), connectionFlags); |
| 419 | } |
| 420 | } |
| 421 | |
| 422 | /** |
| 423 | * Collects statistics about database connection memory usage. |
| 424 | * |
| 425 | * @param dbStatsList The list to populate. |
| 426 | */ |
| 427 | public void collectDbStats(ArrayList<DbStats> dbStatsList) { |
| 428 | synchronized (mLock) { |
| 429 | if (mAvailablePrimaryConnection != null) { |
| 430 | mAvailablePrimaryConnection.collectDbStats(dbStatsList); |
| 431 | } |
| 432 | |
| 433 | for (SQLiteConnection connection : mAvailableNonPrimaryConnections) { |
| 434 | connection.collectDbStats(dbStatsList); |
| 435 | } |
| 436 | |
| 437 | for (SQLiteConnection connection : mAcquiredConnections.keySet()) { |
| 438 | connection.collectDbStatsUnsafe(dbStatsList); |
| 439 | } |
| 440 | } |
| 441 | } |
| 442 | |
| 443 | // Might throw. |
Jeff Brown | 559d064 | 2012-02-29 10:19:12 -0800 | [diff] [blame] | 444 | private SQLiteConnection openConnectionLocked(SQLiteDatabaseConfiguration configuration, |
| 445 | boolean primaryConnection) { |
Jeff Brown | e5360fb | 2011-10-31 17:48:13 -0700 | [diff] [blame] | 446 | final int connectionId = mNextConnectionId++; |
Jeff Brown | 559d064 | 2012-02-29 10:19:12 -0800 | [diff] [blame] | 447 | return SQLiteConnection.open(this, configuration, |
Jeff Brown | e5360fb | 2011-10-31 17:48:13 -0700 | [diff] [blame] | 448 | connectionId, primaryConnection); // might throw |
| 449 | } |
| 450 | |
| 451 | void onConnectionLeaked() { |
| 452 | // This code is running inside of the SQLiteConnection finalizer. |
| 453 | // |
| 454 | // We don't know whether it is just the connection that has been finalized (and leaked) |
| 455 | // or whether the connection pool has also been or is about to be finalized. |
| 456 | // Consequently, it would be a bad idea to try to grab any locks or to |
| 457 | // do any significant work here. So we do the simplest possible thing and |
| 458 | // set a flag. waitForConnection() periodically checks this flag (when it |
| 459 | // times out) so that it can recover from leaked connections and wake |
| 460 | // itself or other threads up if necessary. |
| 461 | // |
| 462 | // You might still wonder why we don't try to do more to wake up the waiters |
| 463 | // immediately. First, as explained above, it would be hard to do safely |
| 464 | // unless we started an extra Thread to function as a reference queue. Second, |
| 465 | // this is never supposed to happen in normal operation. Third, there is no |
| 466 | // guarantee that the GC will actually detect the leak in a timely manner so |
| 467 | // it's not all that important that we recover from the leak in a timely manner |
| 468 | // either. Fourth, if a badly behaved application finds itself hung waiting for |
| 469 | // several seconds while waiting for a leaked connection to be detected and recreated, |
| 470 | // then perhaps its authors will have added incentive to fix the problem! |
| 471 | |
| 472 | Log.w(TAG, "A SQLiteConnection object for database '" |
| 473 | + mConfiguration.label + "' was leaked! Please fix your application " |
| 474 | + "to end transactions in progress properly and to close the database " |
| 475 | + "when it is no longer needed."); |
| 476 | |
| 477 | mConnectionLeaked.set(true); |
| 478 | } |
| 479 | |
| 480 | // Can't throw. |
Jeff Brown | 559d064 | 2012-02-29 10:19:12 -0800 | [diff] [blame] | 481 | private void closeAvailableConnectionsAndLogExceptionsLocked() { |
Jeff Brown | e67ca42 | 2012-03-21 17:24:05 -0700 | [diff] [blame] | 482 | closeAvailableNonPrimaryConnectionsAndLogExceptionsLocked(); |
Jeff Brown | 559d064 | 2012-02-29 10:19:12 -0800 | [diff] [blame] | 483 | |
| 484 | if (mAvailablePrimaryConnection != null) { |
| 485 | closeConnectionAndLogExceptionsLocked(mAvailablePrimaryConnection); |
| 486 | mAvailablePrimaryConnection = null; |
| 487 | } |
| 488 | } |
| 489 | |
| 490 | // Can't throw. |
Jeff Brown | e67ca42 | 2012-03-21 17:24:05 -0700 | [diff] [blame] | 491 | private void closeAvailableNonPrimaryConnectionsAndLogExceptionsLocked() { |
| 492 | final int count = mAvailableNonPrimaryConnections.size(); |
| 493 | for (int i = 0; i < count; i++) { |
| 494 | closeConnectionAndLogExceptionsLocked(mAvailableNonPrimaryConnections.get(i)); |
| 495 | } |
| 496 | mAvailableNonPrimaryConnections.clear(); |
| 497 | } |
| 498 | |
| 499 | // Can't throw. |
Jeff Brown | 559d064 | 2012-02-29 10:19:12 -0800 | [diff] [blame] | 500 | private void closeExcessConnectionsAndLogExceptionsLocked() { |
| 501 | int availableCount = mAvailableNonPrimaryConnections.size(); |
| 502 | while (availableCount-- > mConfiguration.maxConnectionPoolSize - 1) { |
| 503 | SQLiteConnection connection = |
| 504 | mAvailableNonPrimaryConnections.remove(availableCount); |
| 505 | closeConnectionAndLogExceptionsLocked(connection); |
| 506 | } |
| 507 | } |
| 508 | |
| 509 | // Can't throw. |
Jeff Brown | e5360fb | 2011-10-31 17:48:13 -0700 | [diff] [blame] | 510 | private void closeConnectionAndLogExceptionsLocked(SQLiteConnection connection) { |
| 511 | try { |
| 512 | connection.close(); // might throw |
| 513 | } catch (RuntimeException ex) { |
| 514 | Log.e(TAG, "Failed to close connection, its fate is now in the hands " |
| 515 | + "of the merciful GC: " + connection, ex); |
| 516 | } |
| 517 | } |
| 518 | |
| 519 | // Can't throw. |
Jeff Brown | 559d064 | 2012-02-29 10:19:12 -0800 | [diff] [blame] | 520 | private void discardAcquiredConnectionsLocked() { |
| 521 | markAcquiredConnectionsLocked(AcquiredConnectionStatus.DISCARD); |
| 522 | } |
| 523 | |
| 524 | // Can't throw. |
Jeff Brown | e5360fb | 2011-10-31 17:48:13 -0700 | [diff] [blame] | 525 | private void reconfigureAllConnectionsLocked() { |
Jeff Brown | e5360fb | 2011-10-31 17:48:13 -0700 | [diff] [blame] | 526 | if (mAvailablePrimaryConnection != null) { |
| 527 | try { |
| 528 | mAvailablePrimaryConnection.reconfigure(mConfiguration); // might throw |
| 529 | } catch (RuntimeException ex) { |
| 530 | Log.e(TAG, "Failed to reconfigure available primary connection, closing it: " |
| 531 | + mAvailablePrimaryConnection, ex); |
| 532 | closeConnectionAndLogExceptionsLocked(mAvailablePrimaryConnection); |
| 533 | mAvailablePrimaryConnection = null; |
Jeff Brown | e5360fb | 2011-10-31 17:48:13 -0700 | [diff] [blame] | 534 | } |
| 535 | } |
| 536 | |
| 537 | int count = mAvailableNonPrimaryConnections.size(); |
| 538 | for (int i = 0; i < count; i++) { |
| 539 | final SQLiteConnection connection = mAvailableNonPrimaryConnections.get(i); |
| 540 | try { |
| 541 | connection.reconfigure(mConfiguration); // might throw |
| 542 | } catch (RuntimeException ex) { |
| 543 | Log.e(TAG, "Failed to reconfigure available non-primary connection, closing it: " |
| 544 | + connection, ex); |
| 545 | closeConnectionAndLogExceptionsLocked(connection); |
| 546 | mAvailableNonPrimaryConnections.remove(i--); |
| 547 | count -= 1; |
Jeff Brown | e5360fb | 2011-10-31 17:48:13 -0700 | [diff] [blame] | 548 | } |
| 549 | } |
| 550 | |
Jeff Brown | 559d064 | 2012-02-29 10:19:12 -0800 | [diff] [blame] | 551 | markAcquiredConnectionsLocked(AcquiredConnectionStatus.RECONFIGURE); |
| 552 | } |
| 553 | |
| 554 | // Can't throw. |
| 555 | private void markAcquiredConnectionsLocked(AcquiredConnectionStatus status) { |
Jeff Brown | e5360fb | 2011-10-31 17:48:13 -0700 | [diff] [blame] | 556 | if (!mAcquiredConnections.isEmpty()) { |
| 557 | ArrayList<SQLiteConnection> keysToUpdate = new ArrayList<SQLiteConnection>( |
| 558 | mAcquiredConnections.size()); |
Jeff Brown | 559d064 | 2012-02-29 10:19:12 -0800 | [diff] [blame] | 559 | for (Map.Entry<SQLiteConnection, AcquiredConnectionStatus> entry |
| 560 | : mAcquiredConnections.entrySet()) { |
| 561 | AcquiredConnectionStatus oldStatus = entry.getValue(); |
| 562 | if (status != oldStatus |
| 563 | && oldStatus != AcquiredConnectionStatus.DISCARD) { |
Jeff Brown | e5360fb | 2011-10-31 17:48:13 -0700 | [diff] [blame] | 564 | keysToUpdate.add(entry.getKey()); |
| 565 | } |
| 566 | } |
| 567 | final int updateCount = keysToUpdate.size(); |
| 568 | for (int i = 0; i < updateCount; i++) { |
Jeff Brown | 559d064 | 2012-02-29 10:19:12 -0800 | [diff] [blame] | 569 | mAcquiredConnections.put(keysToUpdate.get(i), status); |
Jeff Brown | e5360fb | 2011-10-31 17:48:13 -0700 | [diff] [blame] | 570 | } |
| 571 | } |
Jeff Brown | e5360fb | 2011-10-31 17:48:13 -0700 | [diff] [blame] | 572 | } |
| 573 | |
| 574 | // Might throw. |
Jeff Brown | 75ea64f | 2012-01-25 19:37:13 -0800 | [diff] [blame] | 575 | private SQLiteConnection waitForConnection(String sql, int connectionFlags, |
Jeff Brown | 4c1241d | 2012-02-02 17:05:00 -0800 | [diff] [blame] | 576 | CancellationSignal cancellationSignal) { |
Jeff Brown | e5360fb | 2011-10-31 17:48:13 -0700 | [diff] [blame] | 577 | final boolean wantPrimaryConnection = |
| 578 | (connectionFlags & CONNECTION_FLAG_PRIMARY_CONNECTION_AFFINITY) != 0; |
| 579 | |
| 580 | final ConnectionWaiter waiter; |
| 581 | synchronized (mLock) { |
| 582 | throwIfClosedLocked(); |
| 583 | |
Jeff Brown | 75ea64f | 2012-01-25 19:37:13 -0800 | [diff] [blame] | 584 | // Abort if canceled. |
Jeff Brown | 4c1241d | 2012-02-02 17:05:00 -0800 | [diff] [blame] | 585 | if (cancellationSignal != null) { |
| 586 | cancellationSignal.throwIfCanceled(); |
Jeff Brown | 75ea64f | 2012-01-25 19:37:13 -0800 | [diff] [blame] | 587 | } |
| 588 | |
Jeff Brown | e5360fb | 2011-10-31 17:48:13 -0700 | [diff] [blame] | 589 | // Try to acquire a connection. |
| 590 | SQLiteConnection connection = null; |
| 591 | if (!wantPrimaryConnection) { |
| 592 | connection = tryAcquireNonPrimaryConnectionLocked( |
| 593 | sql, connectionFlags); // might throw |
| 594 | } |
| 595 | if (connection == null) { |
| 596 | connection = tryAcquirePrimaryConnectionLocked(connectionFlags); // might throw |
| 597 | } |
| 598 | if (connection != null) { |
| 599 | return connection; |
| 600 | } |
| 601 | |
| 602 | // No connections available. Enqueue a waiter in priority order. |
| 603 | final int priority = getPriority(connectionFlags); |
| 604 | final long startTime = SystemClock.uptimeMillis(); |
| 605 | waiter = obtainConnectionWaiterLocked(Thread.currentThread(), startTime, |
| 606 | priority, wantPrimaryConnection, sql, connectionFlags); |
| 607 | ConnectionWaiter predecessor = null; |
| 608 | ConnectionWaiter successor = mConnectionWaiterQueue; |
| 609 | while (successor != null) { |
| 610 | if (priority > successor.mPriority) { |
| 611 | waiter.mNext = successor; |
| 612 | break; |
| 613 | } |
| 614 | predecessor = successor; |
| 615 | successor = successor.mNext; |
| 616 | } |
| 617 | if (predecessor != null) { |
| 618 | predecessor.mNext = waiter; |
| 619 | } else { |
| 620 | mConnectionWaiterQueue = waiter; |
| 621 | } |
Jeff Brown | 75ea64f | 2012-01-25 19:37:13 -0800 | [diff] [blame] | 622 | |
Jeff Brown | 4c1241d | 2012-02-02 17:05:00 -0800 | [diff] [blame] | 623 | if (cancellationSignal != null) { |
Jeff Brown | 75ea64f | 2012-01-25 19:37:13 -0800 | [diff] [blame] | 624 | final int nonce = waiter.mNonce; |
Jeff Brown | 4c1241d | 2012-02-02 17:05:00 -0800 | [diff] [blame] | 625 | cancellationSignal.setOnCancelListener(new CancellationSignal.OnCancelListener() { |
Jeff Brown | 75ea64f | 2012-01-25 19:37:13 -0800 | [diff] [blame] | 626 | @Override |
| 627 | public void onCancel() { |
| 628 | synchronized (mLock) { |
| 629 | cancelConnectionWaiterLocked(waiter, nonce); |
| 630 | } |
| 631 | } |
| 632 | }); |
| 633 | } |
Jeff Brown | e5360fb | 2011-10-31 17:48:13 -0700 | [diff] [blame] | 634 | } |
| 635 | |
| 636 | // Park the thread until a connection is assigned or the pool is closed. |
| 637 | // Rethrow an exception from the wait, if we got one. |
| 638 | long busyTimeoutMillis = CONNECTION_POOL_BUSY_MILLIS; |
| 639 | long nextBusyTimeoutTime = waiter.mStartTime + busyTimeoutMillis; |
| 640 | for (;;) { |
| 641 | // Detect and recover from connection leaks. |
| 642 | if (mConnectionLeaked.compareAndSet(true, false)) { |
Jeff Brown | 75ea64f | 2012-01-25 19:37:13 -0800 | [diff] [blame] | 643 | synchronized (mLock) { |
| 644 | wakeConnectionWaitersLocked(); |
| 645 | } |
Jeff Brown | e5360fb | 2011-10-31 17:48:13 -0700 | [diff] [blame] | 646 | } |
| 647 | |
| 648 | // Wait to be unparked (may already have happened), a timeout, or interruption. |
| 649 | LockSupport.parkNanos(this, busyTimeoutMillis * 1000000L); |
| 650 | |
| 651 | // Clear the interrupted flag, just in case. |
| 652 | Thread.interrupted(); |
| 653 | |
| 654 | // Check whether we are done waiting yet. |
| 655 | synchronized (mLock) { |
| 656 | throwIfClosedLocked(); |
| 657 | |
Jeff Brown | 75ea64f | 2012-01-25 19:37:13 -0800 | [diff] [blame] | 658 | final SQLiteConnection connection = waiter.mAssignedConnection; |
| 659 | final RuntimeException ex = waiter.mException; |
| 660 | if (connection != null || ex != null) { |
Jeff Brown | 4c1241d | 2012-02-02 17:05:00 -0800 | [diff] [blame] | 661 | if (cancellationSignal != null) { |
| 662 | cancellationSignal.setOnCancelListener(null); |
Jeff Brown | 75ea64f | 2012-01-25 19:37:13 -0800 | [diff] [blame] | 663 | } |
Jeff Brown | e5360fb | 2011-10-31 17:48:13 -0700 | [diff] [blame] | 664 | recycleConnectionWaiterLocked(waiter); |
Jeff Brown | 75ea64f | 2012-01-25 19:37:13 -0800 | [diff] [blame] | 665 | if (connection != null) { |
| 666 | return connection; |
| 667 | } |
Jeff Brown | e5360fb | 2011-10-31 17:48:13 -0700 | [diff] [blame] | 668 | throw ex; // rethrow! |
| 669 | } |
| 670 | |
| 671 | final long now = SystemClock.uptimeMillis(); |
| 672 | if (now < nextBusyTimeoutTime) { |
| 673 | busyTimeoutMillis = now - nextBusyTimeoutTime; |
| 674 | } else { |
| 675 | logConnectionPoolBusyLocked(now - waiter.mStartTime, connectionFlags); |
| 676 | busyTimeoutMillis = CONNECTION_POOL_BUSY_MILLIS; |
| 677 | nextBusyTimeoutTime = now + busyTimeoutMillis; |
| 678 | } |
| 679 | } |
| 680 | } |
| 681 | } |
| 682 | |
| 683 | // Can't throw. |
Jeff Brown | 75ea64f | 2012-01-25 19:37:13 -0800 | [diff] [blame] | 684 | private void cancelConnectionWaiterLocked(ConnectionWaiter waiter, int nonce) { |
| 685 | if (waiter.mNonce != nonce) { |
| 686 | // Waiter already removed and recycled. |
| 687 | return; |
| 688 | } |
| 689 | |
| 690 | if (waiter.mAssignedConnection != null || waiter.mException != null) { |
| 691 | // Waiter is done waiting but has not woken up yet. |
| 692 | return; |
| 693 | } |
| 694 | |
| 695 | // Waiter must still be waiting. Dequeue it. |
| 696 | ConnectionWaiter predecessor = null; |
| 697 | ConnectionWaiter current = mConnectionWaiterQueue; |
| 698 | while (current != waiter) { |
| 699 | assert current != null; |
| 700 | predecessor = current; |
| 701 | current = current.mNext; |
| 702 | } |
| 703 | if (predecessor != null) { |
| 704 | predecessor.mNext = waiter.mNext; |
| 705 | } else { |
| 706 | mConnectionWaiterQueue = waiter.mNext; |
| 707 | } |
| 708 | |
| 709 | // Send the waiter an exception and unpark it. |
| 710 | waiter.mException = new OperationCanceledException(); |
| 711 | LockSupport.unpark(waiter.mThread); |
| 712 | |
| 713 | // Check whether removing this waiter will enable other waiters to make progress. |
| 714 | wakeConnectionWaitersLocked(); |
| 715 | } |
| 716 | |
| 717 | // Can't throw. |
Jeff Brown | e5360fb | 2011-10-31 17:48:13 -0700 | [diff] [blame] | 718 | private void logConnectionPoolBusyLocked(long waitMillis, int connectionFlags) { |
| 719 | final Thread thread = Thread.currentThread(); |
| 720 | StringBuilder msg = new StringBuilder(); |
| 721 | msg.append("The connection pool for database '").append(mConfiguration.label); |
| 722 | msg.append("' has been unable to grant a connection to thread "); |
| 723 | msg.append(thread.getId()).append(" (").append(thread.getName()).append(") "); |
| 724 | msg.append("with flags 0x").append(Integer.toHexString(connectionFlags)); |
| 725 | msg.append(" for ").append(waitMillis * 0.001f).append(" seconds.\n"); |
| 726 | |
| 727 | ArrayList<String> requests = new ArrayList<String>(); |
| 728 | int activeConnections = 0; |
| 729 | int idleConnections = 0; |
| 730 | if (!mAcquiredConnections.isEmpty()) { |
Jeff Brown | 559d064 | 2012-02-29 10:19:12 -0800 | [diff] [blame] | 731 | for (SQLiteConnection connection : mAcquiredConnections.keySet()) { |
Jeff Brown | e5360fb | 2011-10-31 17:48:13 -0700 | [diff] [blame] | 732 | String description = connection.describeCurrentOperationUnsafe(); |
| 733 | if (description != null) { |
| 734 | requests.add(description); |
| 735 | activeConnections += 1; |
| 736 | } else { |
| 737 | idleConnections += 1; |
| 738 | } |
| 739 | } |
| 740 | } |
| 741 | int availableConnections = mAvailableNonPrimaryConnections.size(); |
| 742 | if (mAvailablePrimaryConnection != null) { |
| 743 | availableConnections += 1; |
| 744 | } |
| 745 | |
| 746 | msg.append("Connections: ").append(activeConnections).append(" active, "); |
| 747 | msg.append(idleConnections).append(" idle, "); |
| 748 | msg.append(availableConnections).append(" available.\n"); |
| 749 | |
| 750 | if (!requests.isEmpty()) { |
| 751 | msg.append("\nRequests in progress:\n"); |
| 752 | for (String request : requests) { |
| 753 | msg.append(" ").append(request).append("\n"); |
| 754 | } |
| 755 | } |
| 756 | |
| 757 | Log.w(TAG, msg.toString()); |
| 758 | } |
| 759 | |
| 760 | // Can't throw. |
| 761 | private void wakeConnectionWaitersLocked() { |
| 762 | // Unpark all waiters that have requests that we can fulfill. |
| 763 | // This method is designed to not throw runtime exceptions, although we might send |
| 764 | // a waiter an exception for it to rethrow. |
| 765 | ConnectionWaiter predecessor = null; |
| 766 | ConnectionWaiter waiter = mConnectionWaiterQueue; |
| 767 | boolean primaryConnectionNotAvailable = false; |
| 768 | boolean nonPrimaryConnectionNotAvailable = false; |
| 769 | while (waiter != null) { |
| 770 | boolean unpark = false; |
| 771 | if (!mIsOpen) { |
| 772 | unpark = true; |
| 773 | } else { |
| 774 | try { |
| 775 | SQLiteConnection connection = null; |
| 776 | if (!waiter.mWantPrimaryConnection && !nonPrimaryConnectionNotAvailable) { |
| 777 | connection = tryAcquireNonPrimaryConnectionLocked( |
| 778 | waiter.mSql, waiter.mConnectionFlags); // might throw |
| 779 | if (connection == null) { |
| 780 | nonPrimaryConnectionNotAvailable = true; |
| 781 | } |
| 782 | } |
| 783 | if (connection == null && !primaryConnectionNotAvailable) { |
| 784 | connection = tryAcquirePrimaryConnectionLocked( |
| 785 | waiter.mConnectionFlags); // might throw |
| 786 | if (connection == null) { |
| 787 | primaryConnectionNotAvailable = true; |
| 788 | } |
| 789 | } |
| 790 | if (connection != null) { |
| 791 | waiter.mAssignedConnection = connection; |
| 792 | unpark = true; |
| 793 | } else if (nonPrimaryConnectionNotAvailable && primaryConnectionNotAvailable) { |
| 794 | // There are no connections available and the pool is still open. |
| 795 | // We cannot fulfill any more connection requests, so stop here. |
| 796 | break; |
| 797 | } |
| 798 | } catch (RuntimeException ex) { |
| 799 | // Let the waiter handle the exception from acquiring a connection. |
| 800 | waiter.mException = ex; |
| 801 | unpark = true; |
| 802 | } |
| 803 | } |
| 804 | |
| 805 | final ConnectionWaiter successor = waiter.mNext; |
| 806 | if (unpark) { |
| 807 | if (predecessor != null) { |
| 808 | predecessor.mNext = successor; |
| 809 | } else { |
| 810 | mConnectionWaiterQueue = successor; |
| 811 | } |
| 812 | waiter.mNext = null; |
| 813 | |
| 814 | LockSupport.unpark(waiter.mThread); |
| 815 | } else { |
| 816 | predecessor = waiter; |
| 817 | } |
| 818 | waiter = successor; |
| 819 | } |
| 820 | } |
| 821 | |
| 822 | // Might throw. |
| 823 | private SQLiteConnection tryAcquirePrimaryConnectionLocked(int connectionFlags) { |
| 824 | // If the primary connection is available, acquire it now. |
| 825 | SQLiteConnection connection = mAvailablePrimaryConnection; |
| 826 | if (connection != null) { |
| 827 | mAvailablePrimaryConnection = null; |
| 828 | finishAcquireConnectionLocked(connection, connectionFlags); // might throw |
| 829 | return connection; |
| 830 | } |
| 831 | |
| 832 | // Make sure that the primary connection actually exists and has just been acquired. |
| 833 | for (SQLiteConnection acquiredConnection : mAcquiredConnections.keySet()) { |
| 834 | if (acquiredConnection.isPrimaryConnection()) { |
| 835 | return null; |
| 836 | } |
| 837 | } |
| 838 | |
| 839 | // Uhoh. No primary connection! Either this is the first time we asked |
| 840 | // for it, or maybe it leaked? |
Jeff Brown | 559d064 | 2012-02-29 10:19:12 -0800 | [diff] [blame] | 841 | connection = openConnectionLocked(mConfiguration, |
| 842 | true /*primaryConnection*/); // might throw |
Jeff Brown | e5360fb | 2011-10-31 17:48:13 -0700 | [diff] [blame] | 843 | finishAcquireConnectionLocked(connection, connectionFlags); // might throw |
| 844 | return connection; |
| 845 | } |
| 846 | |
| 847 | // Might throw. |
| 848 | private SQLiteConnection tryAcquireNonPrimaryConnectionLocked( |
| 849 | String sql, int connectionFlags) { |
| 850 | // Try to acquire the next connection in the queue. |
| 851 | SQLiteConnection connection; |
| 852 | final int availableCount = mAvailableNonPrimaryConnections.size(); |
| 853 | if (availableCount > 1 && sql != null) { |
| 854 | // If we have a choice, then prefer a connection that has the |
| 855 | // prepared statement in its cache. |
| 856 | for (int i = 0; i < availableCount; i++) { |
| 857 | connection = mAvailableNonPrimaryConnections.get(i); |
| 858 | if (connection.isPreparedStatementInCache(sql)) { |
| 859 | mAvailableNonPrimaryConnections.remove(i); |
| 860 | finishAcquireConnectionLocked(connection, connectionFlags); // might throw |
| 861 | return connection; |
| 862 | } |
| 863 | } |
| 864 | } |
| 865 | if (availableCount > 0) { |
| 866 | // Otherwise, just grab the next one. |
| 867 | connection = mAvailableNonPrimaryConnections.remove(availableCount - 1); |
| 868 | finishAcquireConnectionLocked(connection, connectionFlags); // might throw |
| 869 | return connection; |
| 870 | } |
| 871 | |
| 872 | // Expand the pool if needed. |
| 873 | int openConnections = mAcquiredConnections.size(); |
| 874 | if (mAvailablePrimaryConnection != null) { |
| 875 | openConnections += 1; |
| 876 | } |
| 877 | if (openConnections >= mConfiguration.maxConnectionPoolSize) { |
| 878 | return null; |
| 879 | } |
Jeff Brown | 559d064 | 2012-02-29 10:19:12 -0800 | [diff] [blame] | 880 | connection = openConnectionLocked(mConfiguration, |
| 881 | false /*primaryConnection*/); // might throw |
Jeff Brown | e5360fb | 2011-10-31 17:48:13 -0700 | [diff] [blame] | 882 | finishAcquireConnectionLocked(connection, connectionFlags); // might throw |
| 883 | return connection; |
| 884 | } |
| 885 | |
| 886 | // Might throw. |
| 887 | private void finishAcquireConnectionLocked(SQLiteConnection connection, int connectionFlags) { |
| 888 | try { |
| 889 | final boolean readOnly = (connectionFlags & CONNECTION_FLAG_READ_ONLY) != 0; |
| 890 | connection.setOnlyAllowReadOnlyOperations(readOnly); |
| 891 | |
Jeff Brown | 559d064 | 2012-02-29 10:19:12 -0800 | [diff] [blame] | 892 | mAcquiredConnections.put(connection, AcquiredConnectionStatus.NORMAL); |
Jeff Brown | e5360fb | 2011-10-31 17:48:13 -0700 | [diff] [blame] | 893 | } catch (RuntimeException ex) { |
| 894 | Log.e(TAG, "Failed to prepare acquired connection for session, closing it: " |
| 895 | + connection +", connectionFlags=" + connectionFlags); |
| 896 | closeConnectionAndLogExceptionsLocked(connection); |
| 897 | throw ex; // rethrow! |
| 898 | } |
| 899 | } |
| 900 | |
| 901 | private boolean isSessionBlockingImportantConnectionWaitersLocked( |
| 902 | boolean holdingPrimaryConnection, int connectionFlags) { |
| 903 | ConnectionWaiter waiter = mConnectionWaiterQueue; |
| 904 | if (waiter != null) { |
| 905 | final int priority = getPriority(connectionFlags); |
| 906 | do { |
| 907 | // Only worry about blocked connections that have same or lower priority. |
| 908 | if (priority > waiter.mPriority) { |
| 909 | break; |
| 910 | } |
| 911 | |
| 912 | // If we are holding the primary connection then we are blocking the waiter. |
| 913 | // Likewise, if we are holding a non-primary connection and the waiter |
| 914 | // would accept a non-primary connection, then we are blocking the waier. |
| 915 | if (holdingPrimaryConnection || !waiter.mWantPrimaryConnection) { |
| 916 | return true; |
| 917 | } |
| 918 | |
| 919 | waiter = waiter.mNext; |
| 920 | } while (waiter != null); |
| 921 | } |
| 922 | return false; |
| 923 | } |
| 924 | |
| 925 | private static int getPriority(int connectionFlags) { |
| 926 | return (connectionFlags & CONNECTION_FLAG_INTERACTIVE) != 0 ? 1 : 0; |
| 927 | } |
| 928 | |
| 929 | private void throwIfClosedLocked() { |
| 930 | if (!mIsOpen) { |
| 931 | throw new IllegalStateException("Cannot perform this operation " |
Jeff Brown | 559d064 | 2012-02-29 10:19:12 -0800 | [diff] [blame] | 932 | + "because the connection pool has been closed."); |
Jeff Brown | e5360fb | 2011-10-31 17:48:13 -0700 | [diff] [blame] | 933 | } |
| 934 | } |
| 935 | |
| 936 | private ConnectionWaiter obtainConnectionWaiterLocked(Thread thread, long startTime, |
| 937 | int priority, boolean wantPrimaryConnection, String sql, int connectionFlags) { |
| 938 | ConnectionWaiter waiter = mConnectionWaiterPool; |
| 939 | if (waiter != null) { |
| 940 | mConnectionWaiterPool = waiter.mNext; |
| 941 | waiter.mNext = null; |
| 942 | } else { |
| 943 | waiter = new ConnectionWaiter(); |
| 944 | } |
| 945 | waiter.mThread = thread; |
| 946 | waiter.mStartTime = startTime; |
| 947 | waiter.mPriority = priority; |
| 948 | waiter.mWantPrimaryConnection = wantPrimaryConnection; |
| 949 | waiter.mSql = sql; |
| 950 | waiter.mConnectionFlags = connectionFlags; |
| 951 | return waiter; |
| 952 | } |
| 953 | |
| 954 | private void recycleConnectionWaiterLocked(ConnectionWaiter waiter) { |
| 955 | waiter.mNext = mConnectionWaiterPool; |
| 956 | waiter.mThread = null; |
| 957 | waiter.mSql = null; |
| 958 | waiter.mAssignedConnection = null; |
| 959 | waiter.mException = null; |
Jeff Brown | 75ea64f | 2012-01-25 19:37:13 -0800 | [diff] [blame] | 960 | waiter.mNonce += 1; |
Jeff Brown | e5360fb | 2011-10-31 17:48:13 -0700 | [diff] [blame] | 961 | mConnectionWaiterPool = waiter; |
| 962 | } |
| 963 | |
| 964 | /** |
| 965 | * Dumps debugging information about this connection pool. |
| 966 | * |
| 967 | * @param printer The printer to receive the dump, not null. |
Jeff Brown | a9be415 | 2012-01-18 15:29:57 -0800 | [diff] [blame] | 968 | * @param verbose True to dump more verbose information. |
Jeff Brown | e5360fb | 2011-10-31 17:48:13 -0700 | [diff] [blame] | 969 | */ |
Jeff Brown | a9be415 | 2012-01-18 15:29:57 -0800 | [diff] [blame] | 970 | public void dump(Printer printer, boolean verbose) { |
Jeff Brown | e5360fb | 2011-10-31 17:48:13 -0700 | [diff] [blame] | 971 | Printer indentedPrinter = PrefixPrinter.create(printer, " "); |
| 972 | synchronized (mLock) { |
| 973 | printer.println("Connection pool for " + mConfiguration.path + ":"); |
| 974 | printer.println(" Open: " + mIsOpen); |
| 975 | printer.println(" Max connections: " + mConfiguration.maxConnectionPoolSize); |
| 976 | |
| 977 | printer.println(" Available primary connection:"); |
| 978 | if (mAvailablePrimaryConnection != null) { |
Jeff Brown | a9be415 | 2012-01-18 15:29:57 -0800 | [diff] [blame] | 979 | mAvailablePrimaryConnection.dump(indentedPrinter, verbose); |
Jeff Brown | e5360fb | 2011-10-31 17:48:13 -0700 | [diff] [blame] | 980 | } else { |
| 981 | indentedPrinter.println("<none>"); |
| 982 | } |
| 983 | |
| 984 | printer.println(" Available non-primary connections:"); |
| 985 | if (!mAvailableNonPrimaryConnections.isEmpty()) { |
| 986 | final int count = mAvailableNonPrimaryConnections.size(); |
| 987 | for (int i = 0; i < count; i++) { |
Jeff Brown | a9be415 | 2012-01-18 15:29:57 -0800 | [diff] [blame] | 988 | mAvailableNonPrimaryConnections.get(i).dump(indentedPrinter, verbose); |
Jeff Brown | e5360fb | 2011-10-31 17:48:13 -0700 | [diff] [blame] | 989 | } |
| 990 | } else { |
| 991 | indentedPrinter.println("<none>"); |
| 992 | } |
| 993 | |
| 994 | printer.println(" Acquired connections:"); |
| 995 | if (!mAcquiredConnections.isEmpty()) { |
Jeff Brown | 559d064 | 2012-02-29 10:19:12 -0800 | [diff] [blame] | 996 | for (Map.Entry<SQLiteConnection, AcquiredConnectionStatus> entry : |
Jeff Brown | e5360fb | 2011-10-31 17:48:13 -0700 | [diff] [blame] | 997 | mAcquiredConnections.entrySet()) { |
| 998 | final SQLiteConnection connection = entry.getKey(); |
Jeff Brown | a9be415 | 2012-01-18 15:29:57 -0800 | [diff] [blame] | 999 | connection.dumpUnsafe(indentedPrinter, verbose); |
Jeff Brown | 559d064 | 2012-02-29 10:19:12 -0800 | [diff] [blame] | 1000 | indentedPrinter.println(" Status: " + entry.getValue()); |
Jeff Brown | e5360fb | 2011-10-31 17:48:13 -0700 | [diff] [blame] | 1001 | } |
| 1002 | } else { |
| 1003 | indentedPrinter.println("<none>"); |
| 1004 | } |
| 1005 | |
| 1006 | printer.println(" Connection waiters:"); |
| 1007 | if (mConnectionWaiterQueue != null) { |
| 1008 | int i = 0; |
| 1009 | final long now = SystemClock.uptimeMillis(); |
| 1010 | for (ConnectionWaiter waiter = mConnectionWaiterQueue; waiter != null; |
| 1011 | waiter = waiter.mNext, i++) { |
| 1012 | indentedPrinter.println(i + ": waited for " |
| 1013 | + ((now - waiter.mStartTime) * 0.001f) |
| 1014 | + " ms - thread=" + waiter.mThread |
| 1015 | + ", priority=" + waiter.mPriority |
| 1016 | + ", sql='" + waiter.mSql + "'"); |
| 1017 | } |
| 1018 | } else { |
| 1019 | indentedPrinter.println("<none>"); |
| 1020 | } |
| 1021 | } |
| 1022 | } |
| 1023 | |
| 1024 | @Override |
| 1025 | public String toString() { |
| 1026 | return "SQLiteConnectionPool: " + mConfiguration.path; |
| 1027 | } |
| 1028 | |
| 1029 | private static final class ConnectionWaiter { |
| 1030 | public ConnectionWaiter mNext; |
| 1031 | public Thread mThread; |
| 1032 | public long mStartTime; |
| 1033 | public int mPriority; |
| 1034 | public boolean mWantPrimaryConnection; |
| 1035 | public String mSql; |
| 1036 | public int mConnectionFlags; |
| 1037 | public SQLiteConnection mAssignedConnection; |
| 1038 | public RuntimeException mException; |
Jeff Brown | 75ea64f | 2012-01-25 19:37:13 -0800 | [diff] [blame] | 1039 | public int mNonce; |
Jeff Brown | e5360fb | 2011-10-31 17:48:13 -0700 | [diff] [blame] | 1040 | } |
| 1041 | } |