Isn't it cool when it comes true? However, the ultralite.NET api seems only works on windows (desktop or mobile).

So I have spent quite some time on building a POC of this and what I have achieved so far:

• De-compiled Sap.Data.UltraLite.dll and make some changes so it compiles with MonoAndroid
• created, built and ran an Android application written in C# using above API
• This android application has successfully loaded the native ultralite library: libultralitej17.so
• A function to create database in libultralitej17.so is invoked from C# but resulted an error

Although I am blocked currently, I believe so far that this approach should be doable. However what confused me is: the API exposed by libultralitej17.so seems not same with what documented on Ultralite C++ API reference at dcx.sap.com. Appreciated if anyone could guide me on how to:

• get a ultralite android native library which expose the same APIs as documented on Ultralite C++ API reference at dcx.sap.com
• or better, a ultralite .NET API that can be used on Xamarin (that is to say, not limited to Windows)

Bellow is the details of what I have done and encountered:

NOTE:

• libultralitej17.so is coming from UltraLite\UltraLiteJ\Android\ARM
• The function invokded in libultralitej17.so is _ZN17ULDatabaseManager14CreateDatabaseEPKcS1_P7ULError. There are another 2 functions relate to "database creation", one is JNI method for Java Java_com_sap_ultralitejni17_implementation_JniDbMgr_createDatabase, the other one is ulpp_create_database_a and I choose the weirdest one by intuition. Anyone can tell me why there could be such a name, name mangling in C++, perhaps?
• This is the C# code to call the native function:

[DllImport("libultralitej17.so", CharSet = CharSet.Unicode, EntryPoint = "_ZN17ULDatabaseManager14CreateDatabaseEPKcS1_P7ULError")] public unsafe static extern bool ULNativeDBMgrCreateDatabase(string connParms, string createParms); public unsafe bool DBMgrCreateDatabase(string connParms, string createParms) { return ULStandAloneIface.ULNativeDBMgrCreateDatabase(connParms, createParms); }

• The passed in params: connParams->"DBF=test.udb", createParams->"checksum_level=2"
• The resulted error:

at <unknown> <0xffffffff> 05-10 17:30:49.110 E/mono-rt ( 7285): at (wrapper managed-to-native) Sap.Data.UltraLite.ULStandAloneIface.ULNativeDBMgrCreateDatabase (string,string) <IL 0x0003e, 0xffffffff> 05-10 17:30:49.110 E/mono-rt ( 7285): at Sap.Data.UltraLite.ULStandAloneIface.DBMgrCreateDatabase (string,string) [0x00001] in ultralite_android\Sap.Data.UltraLite\ULStandAloneIface.cs:24 05-10 17:30:49.110 E/mono-rt ( 7285): at Sap.Data.UltraLite.ULDatabaseManager.DoCreateDatabase (string,string) [0x0002e] in ultralite_android\Sap.Data.UltraLite\ULDatabaseManager.cs:81 05-10 17:30:49.111 E/mono-rt ( 7285): at Sap.Data.UltraLite.ULDatabaseManager.CreateDatabase (string,string) [0x00001] in ultralite_android\Sap.Data.UltraLite\ULDatabaseManager.cs:69

Attempting native Android stacktrace:

at ???+0 [0xe0830fe8] at ???+0 [0xe0cc0578]

Got a SIGSEGV while executing native code. This usually indicates a fatal error in the mono runtime or one of the native libraries used by your application.

Fatal signal 11 (SIGSEGV), code 2, fault addr 0xdda301a1 in tid 7285 (tralite_android)