The Tor Browser: mobile/android/base/sqlite/SQLiteBridge.java@b8a032363ba2 (annotated)

mobile/android/base/sqlite/SQLiteBridge.java@b8a032363ba2 (annotated)

mobile/android/base/sqlite/SQLiteBridge.java

Thu, 22 Jan 2015 13:21:57 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Thu, 22 Jan 2015 13:21:57 +0100
branch: TOR_BUG_9701
changeset 15: b8a032363ba2
permissions: -rw-r--r--

Incorporate requested changes from Mozilla in review:
https://bugzilla.mozilla.org/show_bug.cgi?id=1123480#c6

 /* This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this file,
  * You can obtain one at http://mozilla.org/MPL/2.0/. */
 package org.mozilla.gecko.sqlite;
 import android.content.ContentValues;
 import android.database.Cursor;
 import android.database.sqlite.SQLiteDatabase;
 import android.database.sqlite.SQLiteException;
 import android.text.TextUtils;
 import android.util.Log;
 import org.mozilla.gecko.mozglue.RobocopTarget;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Map.Entry;
 /*
  * This class allows using the mozsqlite3 library included with Firefox
  * to read SQLite databases, instead of the Android SQLiteDataBase API,
  * which might use whatever outdated DB is present on the Android system.
  */
 public class SQLiteBridge {
     private static final String LOGTAG = "SQLiteBridge";
     // Path to the database. If this database was not opened with openDatabase, we reopen it every query.
     private String mDb;
     // Pointer to the database if it was opened with openDatabase. 0 implies closed.
     protected volatile long mDbPointer = 0L;
     // Values remembered after a query.
     private long[] mQueryResults;
     private boolean mTransactionSuccess = false;
     private boolean mInTransaction = false;
     private static final int RESULT_INSERT_ROW_ID = 0;
     private static final int RESULT_ROWS_CHANGED = 1;
     // Shamelessly cribbed from db/sqlite3/src/moz.build.
     private static final int DEFAULT_PAGE_SIZE_BYTES = 32768;
     // The same size we use elsewhere.
     private static final int MAX_WAL_SIZE_BYTES = 524288;
     // JNI code in $(topdir)/mozglue/android/..
     private static native MatrixBlobCursor sqliteCall(String aDb, String aQuery,
                                                       String[] aParams,
                                                       long[] aUpdateResult)
         throws SQLiteBridgeException;
     private static native MatrixBlobCursor sqliteCallWithDb(long aDb, String aQuery,
                                                             String[] aParams,
                                                             long[] aUpdateResult)
         throws SQLiteBridgeException;
     private static native long openDatabase(String aDb)
         throws SQLiteBridgeException;
     private static native void closeDatabase(long aDb);
     // Takes the path to the database we want to access.
     @RobocopTarget
     public SQLiteBridge(String aDb) throws SQLiteBridgeException {
         mDb = aDb;
     }
     // Executes a simple line of sql.
     public void execSQL(String sql)
                 throws SQLiteBridgeException {
         internalQuery(sql, null);
     }
     // Executes a simple line of sql. Allow you to bind arguments
     public void execSQL(String sql, String[] bindArgs)
                 throws SQLiteBridgeException {
         internalQuery(sql, bindArgs);
     }
     // Executes a DELETE statement on the database
     public int delete(String table, String whereClause, String[] whereArgs)
                throws SQLiteBridgeException {
         StringBuilder sb = new StringBuilder("DELETE from ");
         sb.append(table);
         if (whereClause != null) {
             sb.append(" WHERE " + whereClause);
         }
         internalQuery(sb.toString(), whereArgs);
         return (int)mQueryResults[RESULT_ROWS_CHANGED];
     }
     public Cursor query(String table,
                         String[] columns,
                         String selection,
                         String[] selectionArgs,
                         String groupBy,
                         String having,
                         String orderBy,
                         String limit)
                throws SQLiteBridgeException {
         StringBuilder sb = new StringBuilder("SELECT ");
         if (columns != null)
             sb.append(TextUtils.join(", ", columns));
         else
             sb.append(" * ");
         sb.append(" FROM ");
         sb.append(table);
         if (selection != null) {
             sb.append(" WHERE " + selection);
         }
         if (groupBy != null) {
             sb.append(" GROUP BY " + groupBy);
         }
         if (having != null) {
             sb.append(" HAVING " + having);
         }
         if (orderBy != null) {
             sb.append(" ORDER BY " + orderBy);
         }
         if (limit != null) {
             sb.append(" " + limit);
         }
         return rawQuery(sb.toString(), selectionArgs);
     }
     @RobocopTarget
     public Cursor rawQuery(String sql, String[] selectionArgs)
         throws SQLiteBridgeException {
         return internalQuery(sql, selectionArgs);
     }
     public long insert(String table, String nullColumnHack, ContentValues values)
                throws SQLiteBridgeException {
         if (values == null)
             return 0;
         ArrayList<String> valueNames = new ArrayList<String>();
         ArrayList<String> valueBinds = new ArrayList<String>();
         ArrayList<String> keyNames = new ArrayList<String>();
         for (Entry<String, Object> value : values.valueSet()) {
             keyNames.add(value.getKey());
             Object val = value.getValue();
             if (val == null) {
                 valueNames.add("NULL");
             } else {
                 valueNames.add("?");
                 valueBinds.add(val.toString());
             }
         }
         StringBuilder sb = new StringBuilder("INSERT into ");
         sb.append(table);
         sb.append(" (");
         sb.append(TextUtils.join(", ", keyNames));
         sb.append(")");
         // XXX - Do we need to bind these values?
         sb.append(" VALUES (");
         sb.append(TextUtils.join(", ", valueNames));
         sb.append(") ");
         String[] binds = new String[valueBinds.size()];
         valueBinds.toArray(binds);
         internalQuery(sb.toString(), binds);
         return mQueryResults[RESULT_INSERT_ROW_ID];
     }
     public int update(String table, ContentValues values, String whereClause, String[] whereArgs)
                throws SQLiteBridgeException {
         if (values == null)
             return 0;
         ArrayList<String> valueNames = new ArrayList<String>();
         StringBuilder sb = new StringBuilder("UPDATE ");
         sb.append(table);
         sb.append(" SET ");
         boolean isFirst = true;
         for (Entry<String, Object> value : values.valueSet()) {
             if (isFirst)
                 isFirst = false;
             else
                 sb.append(", ");
             sb.append(value.getKey());
             Object val = value.getValue();
             if (val == null) {
                 sb.append(" = NULL");
             } else {
                 sb.append(" = ?");
                 valueNames.add(val.toString());
             }
         }
         if (!TextUtils.isEmpty(whereClause)) {
             sb.append(" WHERE ");
             sb.append(whereClause);
             valueNames.addAll(Arrays.asList(whereArgs));
         }
         String[] binds = new String[valueNames.size()];
         valueNames.toArray(binds);
         internalQuery(sb.toString(), binds);
         return (int)mQueryResults[RESULT_ROWS_CHANGED];
     }
     public int getVersion()
                throws SQLiteBridgeException {
         Cursor cursor = internalQuery("PRAGMA user_version", null);
         int ret = -1;
         if (cursor != null) {
             cursor.moveToFirst();
             String version = cursor.getString(0);
             ret = Integer.parseInt(version);
         }
         return ret;
     }
     // Do an SQL query, substituting the parameters in the query with the passed
     // parameters. The parameters are substituted in order: named parameters
     // are not supported.
     private Cursor internalQuery(String aQuery, String[] aParams)
         throws SQLiteBridgeException {
         mQueryResults = new long[2];
         if (isOpen()) {
             return sqliteCallWithDb(mDbPointer, aQuery, aParams, mQueryResults);
         }
         return sqliteCall(mDb, aQuery, aParams, mQueryResults);
     }
     /*
      * The second two parameters here are just provided for compatibility with SQLiteDatabase
      * Support for them is not currently implemented.
     */
     public static SQLiteBridge openDatabase(String path, SQLiteDatabase.CursorFactory factory, int flags)
         throws SQLiteException {
         if (factory != null) {
             throw new RuntimeException("factory not supported.");
         }
         if (flags != 0) {
             throw new RuntimeException("flags not supported.");
         }
         SQLiteBridge bridge = null;
         try {
             bridge = new SQLiteBridge(path);
             bridge.mDbPointer = SQLiteBridge.openDatabase(path);
         } catch (SQLiteBridgeException ex) {
             // Catch and rethrow as a SQLiteException to match SQLiteDatabase.
             throw new SQLiteException(ex.getMessage());
         }
         prepareWAL(bridge);
         return bridge;
     }
     public void close() {
         if (isOpen()) {
           closeDatabase(mDbPointer);
         }
         mDbPointer = 0L;
     }
     public boolean isOpen() {
         return mDbPointer != 0;
     }
     public void beginTransaction() throws SQLiteBridgeException {
         if (inTransaction()) {
             throw new SQLiteBridgeException("Nested transactions are not supported");
         }
         execSQL("BEGIN EXCLUSIVE");
         mTransactionSuccess = false;
         mInTransaction = true;
     }
     public void beginTransactionNonExclusive() throws SQLiteBridgeException {
         if (inTransaction()) {
             throw new SQLiteBridgeException("Nested transactions are not supported");
         }
         execSQL("BEGIN IMMEDIATE");
         mTransactionSuccess = false;
         mInTransaction = true;
     }
     public void endTransaction() {
         if (!inTransaction())
             return;
         try {
           if (mTransactionSuccess) {
               execSQL("COMMIT TRANSACTION");
           } else {
               execSQL("ROLLBACK TRANSACTION");
           }
         } catch(SQLiteBridgeException ex) {
             Log.e(LOGTAG, "Error ending transaction", ex);
         }
         mInTransaction = false;
         mTransactionSuccess = false;
     }
     public void setTransactionSuccessful() throws SQLiteBridgeException {
         if (!inTransaction()) {
             throw new SQLiteBridgeException("setTransactionSuccessful called outside a transaction");
         }
         mTransactionSuccess = true;
     }
     public boolean inTransaction() {
         return mInTransaction;
     }
     @Override
     public void finalize() {
         if (isOpen()) {
             Log.e(LOGTAG, "Bridge finalized without closing the database");
             close();
         }
     }
     private static void prepareWAL(final SQLiteBridge bridge) {
         // Prepare for WAL mode. If we can, we switch to journal_mode=WAL, then
         // set the checkpoint size appropriately. If we can't, then we fall back
         // to truncating and synchronous writes.
         final Cursor cursor = bridge.internalQuery("PRAGMA journal_mode=WAL", null);
         try {
             if (cursor.moveToFirst()) {
                 String journalMode = cursor.getString(0);
                 Log.d(LOGTAG, "Journal mode: " + journalMode);
                 if ("wal".equals(journalMode)) {
                     // Success! Let's make sure we autocheckpoint at a reasonable interval.
                     final int pageSizeBytes = bridge.getPageSizeBytes();
                     final int checkpointPageCount = MAX_WAL_SIZE_BYTES / pageSizeBytes;
                     bridge.internalQuery("PRAGMA wal_autocheckpoint=" + checkpointPageCount, null).close();
                 } else {
                     if (!"truncate".equals(journalMode)) {
                         Log.w(LOGTAG, "Unable to activate WAL journal mode. Using truncate instead.");
                         bridge.internalQuery("PRAGMA journal_mode=TRUNCATE", null).close();
                     }
                     Log.w(LOGTAG, "Not using WAL mode: using synchronous=FULL instead.");
                     bridge.internalQuery("PRAGMA synchronous=FULL", null).close();
                 }
             }
         } finally {
             cursor.close();
         }
     }
     private int getPageSizeBytes() {
         if (!isOpen()) {
             throw new IllegalStateException("Database not open.");
         }
         final Cursor cursor = internalQuery("PRAGMA page_size", null);
         try {
             if (!cursor.moveToFirst()) {
                 Log.w(LOGTAG, "Unable to retrieve page size.");
                 return DEFAULT_PAGE_SIZE_BYTES;
             }
             return cursor.getInt(0);
         } finally {
             cursor.close();
         }
     }
 }

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mobile/android/base/sqlite/SQLiteBridge.java@b8a032363ba2 (annotated)

mobile/android/base/sqlite/SQLiteBridge.java