Fyodor Kupolov | ee90c03 | 2017-12-12 11:52:57 -0800 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 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 android.database.sqlite; |
| 18 | |
| 19 | import android.app.ActivityThread; |
| 20 | import android.app.Application; |
| 21 | import android.provider.Settings; |
| 22 | import android.text.TextUtils; |
| 23 | import android.util.KeyValueListParser; |
| 24 | import android.util.Log; |
| 25 | |
| 26 | import com.android.internal.annotations.VisibleForTesting; |
| 27 | |
| 28 | /** |
| 29 | * Helper class for accessing |
| 30 | * {@link Settings.Global#SQLITE_COMPATIBILITY_WAL_FLAGS global compatibility WAL settings}. |
| 31 | * |
| 32 | * <p>The value of {@link Settings.Global#SQLITE_COMPATIBILITY_WAL_FLAGS} is cached on first access |
| 33 | * for consistent behavior across all connections opened in the process. |
| 34 | * @hide |
| 35 | */ |
| 36 | public class SQLiteCompatibilityWalFlags { |
| 37 | |
| 38 | private static final String TAG = "SQLiteCompatibilityWalFlags"; |
| 39 | |
Fyodor Kupolov | 7fcd659 | 2017-12-15 11:56:36 -0800 | [diff] [blame] | 40 | private static volatile boolean sInitialized; |
Fyodor Kupolov | ee90c03 | 2017-12-12 11:52:57 -0800 | [diff] [blame] | 41 | private static volatile boolean sFlagsSet; |
| 42 | private static volatile boolean sCompatibilityWalSupported; |
| 43 | private static volatile String sWALSyncMode; |
| 44 | // This flag is used to avoid recursive initialization due to circular dependency on Settings |
| 45 | private static volatile boolean sCallingGlobalSettings; |
| 46 | |
| 47 | /** |
| 48 | * @hide |
| 49 | */ |
| 50 | @VisibleForTesting |
| 51 | public static boolean areFlagsSet() { |
| 52 | initIfNeeded(); |
| 53 | return sFlagsSet; |
| 54 | } |
| 55 | |
| 56 | /** |
| 57 | * @hide |
| 58 | */ |
| 59 | @VisibleForTesting |
| 60 | public static boolean isCompatibilityWalSupported() { |
| 61 | initIfNeeded(); |
| 62 | return sCompatibilityWalSupported; |
| 63 | } |
| 64 | |
| 65 | /** |
| 66 | * @hide |
| 67 | */ |
| 68 | @VisibleForTesting |
| 69 | public static String getWALSyncMode() { |
| 70 | initIfNeeded(); |
| 71 | return sWALSyncMode; |
| 72 | } |
| 73 | |
| 74 | private static void initIfNeeded() { |
| 75 | if (sInitialized || sCallingGlobalSettings) { |
| 76 | return; |
| 77 | } |
| 78 | ActivityThread activityThread = ActivityThread.currentActivityThread(); |
| 79 | Application app = activityThread == null ? null : activityThread.getApplication(); |
| 80 | String flags = null; |
| 81 | if (app == null) { |
| 82 | Log.w(TAG, "Cannot read global setting " |
| 83 | + Settings.Global.SQLITE_COMPATIBILITY_WAL_FLAGS + " - " |
| 84 | + "Application state not available"); |
| 85 | } else { |
| 86 | try { |
| 87 | sCallingGlobalSettings = true; |
| 88 | flags = Settings.Global.getString(app.getContentResolver(), |
| 89 | Settings.Global.SQLITE_COMPATIBILITY_WAL_FLAGS); |
| 90 | } finally { |
| 91 | sCallingGlobalSettings = false; |
| 92 | } |
| 93 | } |
| 94 | |
| 95 | init(flags); |
| 96 | } |
| 97 | |
| 98 | /** |
| 99 | * @hide |
| 100 | */ |
| 101 | @VisibleForTesting |
| 102 | public static void init(String flags) { |
| 103 | if (TextUtils.isEmpty(flags)) { |
| 104 | sInitialized = true; |
| 105 | return; |
| 106 | } |
| 107 | KeyValueListParser parser = new KeyValueListParser(','); |
| 108 | try { |
| 109 | parser.setString(flags); |
| 110 | } catch (IllegalArgumentException e) { |
| 111 | Log.e(TAG, "Setting has invalid format: " + flags, e); |
| 112 | sInitialized = true; |
| 113 | return; |
| 114 | } |
| 115 | sCompatibilityWalSupported = parser.getBoolean("compatibility_wal_supported", |
| 116 | SQLiteGlobal.isCompatibilityWalSupported()); |
| 117 | sWALSyncMode = parser.getString("wal_syncmode", SQLiteGlobal.getWALSyncMode()); |
| 118 | Log.i(TAG, "Read compatibility WAL flags: compatibility_wal_supported=" |
| 119 | + sCompatibilityWalSupported + ", wal_syncmode=" + sWALSyncMode); |
| 120 | sFlagsSet = true; |
| 121 | sInitialized = true; |
| 122 | } |
| 123 | |
| 124 | /** |
| 125 | * @hide |
| 126 | */ |
| 127 | @VisibleForTesting |
| 128 | public static void reset() { |
| 129 | sInitialized = false; |
| 130 | sFlagsSet = false; |
| 131 | sCompatibilityWalSupported = false; |
| 132 | sWALSyncMode = null; |
| 133 | } |
| 134 | } |