| /* |
| * Copyright (C) 2011 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package android.database.sqlite; |
| |
| import android.annotation.TestApi; |
| import android.content.res.Resources; |
| import android.os.StatFs; |
| import android.os.SystemProperties; |
| |
| /** |
| * Provides access to SQLite functions that affect all database connection, |
| * such as memory management. |
| * |
| * The native code associated with SQLiteGlobal is also sets global configuration options |
| * using sqlite3_config() then calls sqlite3_initialize() to ensure that the SQLite |
| * library is properly initialized exactly once before any other framework or application |
| * code has a chance to run. |
| * |
| * Verbose SQLite logging is enabled if the "log.tag.SQLiteLog" property is set to "V". |
| * (per {@link SQLiteDebug#DEBUG_SQL_LOG}). |
| * |
| * @hide |
| */ |
| @TestApi |
| public final class SQLiteGlobal { |
| private static final String TAG = "SQLiteGlobal"; |
| |
| /** @hide */ |
| public static final String SYNC_MODE_FULL = "FULL"; |
| |
| /** @hide */ |
| static final String WIPE_CHECK_FILE_SUFFIX = "-wipecheck"; |
| |
| private static final Object sLock = new Object(); |
| |
| private static int sDefaultPageSize; |
| |
| private static native int nativeReleaseMemory(); |
| |
| /** @hide */ |
| public static volatile String sDefaultSyncMode; |
| |
| private SQLiteGlobal() { |
| } |
| |
| /** |
| * Attempts to release memory by pruning the SQLite page cache and other |
| * internal data structures. |
| * |
| * @return The number of bytes that were freed. |
| */ |
| public static int releaseMemory() { |
| return nativeReleaseMemory(); |
| } |
| |
| /** |
| * Gets the default page size to use when creating a database. |
| */ |
| public static int getDefaultPageSize() { |
| synchronized (sLock) { |
| if (sDefaultPageSize == 0) { |
| // If there is an issue accessing /data, something is so seriously |
| // wrong that we just let the IllegalArgumentException propagate. |
| sDefaultPageSize = new StatFs("/data").getBlockSize(); |
| } |
| return SystemProperties.getInt("debug.sqlite.pagesize", sDefaultPageSize); |
| } |
| } |
| |
| /** |
| * Gets the default journal mode when WAL is not in use. |
| */ |
| public static String getDefaultJournalMode() { |
| return SystemProperties.get("debug.sqlite.journalmode", |
| Resources.getSystem().getString( |
| com.android.internal.R.string.db_default_journal_mode)); |
| } |
| |
| /** |
| * Gets the journal size limit in bytes. |
| */ |
| public static int getJournalSizeLimit() { |
| return SystemProperties.getInt("debug.sqlite.journalsizelimit", |
| Resources.getSystem().getInteger( |
| com.android.internal.R.integer.db_journal_size_limit)); |
| } |
| |
| /** |
| * Gets the default database synchronization mode when WAL is not in use. |
| */ |
| public static String getDefaultSyncMode() { |
| // Use the FULL synchronous mode for system processes by default. |
| String defaultMode = sDefaultSyncMode; |
| if (defaultMode != null) { |
| return defaultMode; |
| } |
| return SystemProperties.get("debug.sqlite.syncmode", |
| Resources.getSystem().getString( |
| com.android.internal.R.string.db_default_sync_mode)); |
| } |
| |
| /** |
| * Gets the database synchronization mode when in WAL mode. |
| */ |
| public static String getWALSyncMode() { |
| // Use the FULL synchronous mode for system processes by default. |
| String defaultMode = sDefaultSyncMode; |
| if (defaultMode != null) { |
| return defaultMode; |
| } |
| return SystemProperties.get("debug.sqlite.wal.syncmode", |
| Resources.getSystem().getString( |
| com.android.internal.R.string.db_wal_sync_mode)); |
| } |
| |
| /** |
| * Gets the WAL auto-checkpoint integer in database pages. |
| */ |
| public static int getWALAutoCheckpoint() { |
| int value = SystemProperties.getInt("debug.sqlite.wal.autocheckpoint", |
| Resources.getSystem().getInteger( |
| com.android.internal.R.integer.db_wal_autocheckpoint)); |
| return Math.max(1, value); |
| } |
| |
| /** |
| * Gets the connection pool size when in WAL mode. |
| */ |
| public static int getWALConnectionPoolSize() { |
| int value = SystemProperties.getInt("debug.sqlite.wal.poolsize", |
| Resources.getSystem().getInteger( |
| com.android.internal.R.integer.db_connection_pool_size)); |
| return Math.max(2, value); |
| } |
| |
| /** |
| * The default number of milliseconds that SQLite connection is allowed to be idle before it |
| * is closed and removed from the pool. |
| */ |
| public static int getIdleConnectionTimeout() { |
| return SystemProperties.getInt("debug.sqlite.idle_connection_timeout", |
| Resources.getSystem().getInteger( |
| com.android.internal.R.integer.db_default_idle_connection_timeout)); |
| } |
| |
| /** |
| * When opening a database, if the WAL file is larger than this size, we'll truncate it. |
| * |
| * (If it's 0, we do not truncate.) |
| * |
| * @hide |
| */ |
| public static long getWALTruncateSize() { |
| final long setting = SQLiteCompatibilityWalFlags.getTruncateSize(); |
| if (setting >= 0) { |
| return setting; |
| } |
| return SystemProperties.getInt("debug.sqlite.wal.truncatesize", |
| Resources.getSystem().getInteger( |
| com.android.internal.R.integer.db_wal_truncate_size)); |
| } |
| |
| /** @hide */ |
| public static boolean checkDbWipe() { |
| return true; |
| } |
| } |