Crash when updating from 6.0.0 to 6.0.2 due to cache database locked

Issue Type

[X] Bug

Description and/or steps/code to reproduce the problem

Update your app with osmdroid 6.0.0 to osmdroid 6.0.2 with a cache database > 400 MB. On first map launch it will crash if tiles are to be downloaded immediately and written with SqlTileWriter.saveFile, because the database is locked. I take this is caused by the database index creation update in #973 ? On second launch it’s working again.

04-19 10:39:39.749 E/SQLiteDatabase: Error inserting tile=[B@cb96fbd expires=1334919638000 provider=Mapnik key=905965568
	android.database.sqlite.SQLiteDatabaseLockedException: database is locked (code 5)
		at android.database.sqlite.SQLiteConnection.nativeExecuteForLastInsertedRowId(Native Method)
		at android.database.sqlite.SQLiteConnection.executeForLastInsertedRowId(SQLiteConnection.java:783)
		at android.database.sqlite.SQLiteSession.executeForLastInsertedRowId(SQLiteSession.java:788)
		at android.database.sqlite.SQLiteStatement.executeInsert(SQLiteStatement.java:86)
		at android.database.sqlite.SQLiteDatabase.insertWithOnConflict(SQLiteDatabase.java:1548)
		at android.database.sqlite.SQLiteDatabase.replace(SQLiteDatabase.java:1464)
		at org.osmdroid.tileprovider.modules.SqlTileWriter.saveFile(SqlTileWriter.java:150)
		at org.osmdroid.tileprovider.modules.MapTileDownloader$TileLoader.loadTile(MapTileDownloader.java:255)
		at org.osmdroid.tileprovider.modules.MapTileModuleProviderBase$TileLoader.run(MapTileModuleProviderBase.java:315)
		at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1162)
		at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:636)
		at java.lang.Thread.run(Thread.java:764)
04-19 10:39:42.265 E/SQLiteDatabase: Error inserting tile=[B@5d34fd6 expires=1334880026000 provider=Mapnik key=905973758
	android.database.sqlite.SQLiteDatabaseLockedException: database is locked (code 5)
		at android.database.sqlite.SQLiteConnection.nativeExecuteForLastInsertedRowId(Native Method)
		at android.database.sqlite.SQLiteConnection.executeForLastInsertedRowId(SQLiteConnection.java:783)
		at android.database.sqlite.SQLiteSession.executeForLastInsertedRowId(SQLiteSession.java:788)
		at android.database.sqlite.SQLiteStatement.executeInsert(SQLiteStatement.java:86)
		at android.database.sqlite.SQLiteDatabase.insertWithOnConflict(SQLiteDatabase.java:1548)
		at android.database.sqlite.SQLiteDatabase.replace(SQLiteDatabase.java:1464)
		at org.osmdroid.tileprovider.modules.SqlTileWriter.saveFile(SqlTileWriter.java:150)
		at org.osmdroid.tileprovider.modules.MapTileDownloader$TileLoader.loadTile(MapTileDownloader.java:255)
		at org.osmdroid.tileprovider.modules.MapTileModuleProviderBase$TileLoader.run(MapTileModuleProviderBase.java:315)
		at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1162)
		at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:636)
		at java.lang.Thread.run(Thread.java:764)
04-19 10:39:42.578 E/AndroidRuntime: FATAL EXCEPTION: Thread-4
	java.lang.NullPointerException: Attempt to invoke virtual method 'long java.io.File.length()' on a null object reference
		at org.osmdroid.tileprovider.modules.SqlTileWriter.runCleanupOperation(SqlTileWriter.java:114)
		at org.osmdroid.tileprovider.modules.SqlTileWriter$1.run(SqlTileWriter.java:69)
		at org.osmdroid.util.GarbageCollector$1.run(GarbageCollector.java:31)
		at java.lang.Thread.run(Thread.java:764)

If it’s a bug, version(s) of android this affects:

All

Version of osmdroid the issue relates to:

6.0.2

[InI4]

Didn’t read the code yet, but the problem is, that index creation may take long. Question is, if you can provide an API call to trigger early index creation. I.e. my app has a splash screen, it would be easy to trigger index creation then and would run while various other things initialize and before the map activity is launched.

[secaw]

@monsieurtanuki Did some tests now:

• DB Update is working without crash
• Update (first launch with new version) on older device (Xperia Z1 Lollipop) with cache.db > 500MB is taking about 10 seconds! No map tiles shown during this process. End users probably need to be notified.

On second test I deleted updated cache.db / cache.db-journal and recopied old ones, with the result of ongoing logs of android.database.sqlite.SQLiteReadOnlyDatabaseException: attempt to write a readonly database and no tiles shown. Closing the app doesn’t help, just reinstalling / rerunning from AS. I figured, that in the end we indeed need to close the DB. Tested the following in SqlTileWriter.onDetach and it seems to do the trick. Any reason, why we shouldn’t close the DB even when detaching everything else? DB seems to stay locked internally forever…

@Override
public void onDetach() {
    if(mDb != null) {
        mDb.close();
        mDb = null;
    }
}