System.Data.SQLite
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Overview
Comment:Some cleanup work. Implement the SQLiteValue helper class.
Downloads: Tarball | ZIP archive | SQL archive
Timelines: family | ancestors | descendants | both | virtualTables
Files: files | file ages | folders
SHA1: 33b2470a683dadaa02d60b71f806707c32dd771a
User & Date: mistachkin 2013-06-07 08:32:49
Context
2013-06-07
08:50
Minor adjustments to previous commit. check-in: a900416795 user: mistachkin tags: virtualTables
08:32
Some cleanup work. Implement the SQLiteValue helper class. check-in: 33b2470a68 user: mistachkin tags: virtualTables
02:45
Rename the SQLiteModule class to SQLiteModuleNoop. Adjustments to method and parameter naming conventions. Initial implementation of xOpen virtual table method. check-in: f5c3afbfb1 user: mistachkin tags: virtualTables
Changes
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Changes to System.Data.SQLite/SQLiteModuleBase.cs.

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namespace System.Data.SQLite
{
    public sealed class SQLiteContext
    {

    }

    ///////////////////////////////////////////////////////////////////////

    public sealed class SQLiteValue
    {



    }









    ///////////////////////////////////////////////////////////////////////





















































    public class SQLiteIndexConstraint
    {
        private SQLiteModuleBase.UnsafeNativeMethods2.sqlite3_index_constraint constraint;
    }

    ///////////////////////////////////////////////////////////////////////

    public class SQLiteIndexOrderBy
    {
        private SQLiteModuleBase.UnsafeNativeMethods2.sqlite3_index_orderby orderBy;
    }

    ///////////////////////////////////////////////////////////////////////

    public class SQLiteIndexConstraintUsage
    {
        private SQLiteModuleBase.UnsafeNativeMethods2.sqlite3_index_constraint_usage constraintUsage;
    }

    ///////////////////////////////////////////////////////////////////////

    public class SQLiteIndex
    {
        SQLiteIndexConstraint[] Constraints;
        SQLiteIndexOrderBy[] OrderBys;


................................................................................
        int idxNum;           /* Number used to identify the index */
        string idxStr;        /* String, possibly obtained from sqlite3_malloc */
        int needToFreeIdxStr; /* Free idxStr using sqlite3_free() if true */
        int orderByConsumed;  /* True if output is already ordered */
        double estimatedCost; /* Estimated cost of using this index */
    }

    ///////////////////////////////////////////////////////////////////////

    public class SQLiteVirtualTableCursor
    {
        internal SQLiteModuleBase.UnsafeNativeMethods2.sqlite3_vtab_cursor cursor;
    }



    [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
    public delegate int xFunc(
        IntPtr pContext,
        int argc,
        [MarshalAs(UnmanagedType.LPArray, SizeParamIndex = 1)]
        IntPtr[] argv
    );



    public interface ISQLiteNativeModule
    {
        SQLiteErrorCode xCreate(IntPtr pDb, IntPtr pAux, int argc, ref IntPtr[] argv, ref IntPtr pVtab, ref IntPtr pError);
        SQLiteErrorCode xConnect(IntPtr pDb, IntPtr pAux, int argc, ref IntPtr[] argv, ref IntPtr pVtab, ref IntPtr pError);
        SQLiteErrorCode xBestIndex(IntPtr pVtab, IntPtr index);
        SQLiteErrorCode xDisconnect(IntPtr pVtab);
................................................................................
        SQLiteErrorCode xRollback(IntPtr pVtab);
        SQLiteErrorCode xFindFunction(IntPtr pVtab, int nArg, IntPtr zName, ref xFunc pxFunc, ref IntPtr ppArg);
        SQLiteErrorCode xRename(IntPtr pVtab, IntPtr zNew);
        SQLiteErrorCode xSavepoint(IntPtr pVtab, int iSavepoint);
        SQLiteErrorCode xRelease(IntPtr pVtab, int iSavepoint);
        SQLiteErrorCode xRollbackTo(IntPtr pVtab, int iSavepoint);
    }



    public interface ISQLiteManagedModule
    {
        bool Declared { get; }

        SQLiteErrorCode Create(SQLiteConnection connection, IntPtr pClientData, string[] argv, ref string error);
        SQLiteErrorCode Connect(SQLiteConnection connection, IntPtr pClientData, string[] argv, ref string error);
................................................................................
        SQLiteErrorCode Rollback();
        SQLiteErrorCode FindFunction(string zName, ref SQLiteFunction function, object[] args);
        SQLiteErrorCode Rename(string zNew);
        SQLiteErrorCode Savepoint(int iSavepoint);
        SQLiteErrorCode Release(int iSavepoint);
        SQLiteErrorCode RollbackTo(int iSavepoint);
    }



#if NET_40
    [SecurityCritical()]
#else
    [SecurityPermission(SecurityAction.LinkDemand, UnmanagedCode = true)]
#endif
    public abstract class SQLiteModuleBase : ISQLiteManagedModule, ISQLiteNativeModule,  IDisposable
................................................................................
                ref IntPtr[] argv,
                ref IntPtr pVtab,
                ref IntPtr pError
            );

            [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
            public delegate SQLiteErrorCode xBestIndex(
                [MarshalAs(UnmanagedType.LPStruct)]
                IntPtr pVtab,
                [MarshalAs(UnmanagedType.LPStruct)]
                IntPtr index
            );

            [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
            public delegate SQLiteErrorCode xDisconnect(
                [MarshalAs(UnmanagedType.LPStruct)]
                IntPtr pVtab
            );

            [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
            public delegate SQLiteErrorCode xDestroy(
                [MarshalAs(UnmanagedType.LPStruct)]
                IntPtr pVtab
            );

            [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
            public delegate SQLiteErrorCode xOpen(
                [MarshalAs(UnmanagedType.LPStruct)]
                IntPtr pVtab,
                ref IntPtr pCursor
            );

            [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
            public delegate SQLiteErrorCode xClose(
                [MarshalAs(UnmanagedType.LPStruct)]
                IntPtr pCursor
            );

            [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
            public delegate SQLiteErrorCode xFilter(
                [MarshalAs(UnmanagedType.LPStruct)]
                IntPtr pCursor,
                int idxNum,
                IntPtr idxStr,
                int argc,
                IntPtr[] argv
            );

            [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
            public delegate SQLiteErrorCode xNext(
                [MarshalAs(UnmanagedType.LPStruct)]
                IntPtr pCursor
            );

            [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
            public delegate SQLiteErrorCode xEof(
                [MarshalAs(UnmanagedType.LPStruct)]
                IntPtr pCursor
            );

            [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
            public delegate SQLiteErrorCode xColumn(
                [MarshalAs(UnmanagedType.LPStruct)]
                IntPtr pCursor,
                IntPtr pContext,
                int index
            );

            [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
            public delegate SQLiteErrorCode xRowId(
                [MarshalAs(UnmanagedType.LPStruct)]
                IntPtr pCursor,
                ref long rowId
            );

            [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
            public delegate SQLiteErrorCode xUpdate(
                [MarshalAs(UnmanagedType.LPStruct)]
                IntPtr pVtab,
                int nData,
                ref IntPtr apData,
                ref long rowId
            );

            [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
            public delegate SQLiteErrorCode xBegin(
                [MarshalAs(UnmanagedType.LPStruct)]
                IntPtr pVtab
            );

            [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
            public delegate SQLiteErrorCode xSync(
                [MarshalAs(UnmanagedType.LPStruct)]
                IntPtr pVtab
            );

            [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
            public delegate SQLiteErrorCode xCommit(
                [MarshalAs(UnmanagedType.LPStruct)]
                IntPtr pVtab
            );

            [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
            public delegate SQLiteErrorCode xRollback(
                [MarshalAs(UnmanagedType.LPStruct)]
                IntPtr pVtab
            );

            [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
            public delegate SQLiteErrorCode xFindFunction(
                [MarshalAs(UnmanagedType.LPStruct)]
                IntPtr pVtab,
                int nArg,
                IntPtr zName,
                ref xFunc pxFunc,
                ref IntPtr ppArg
            );

            [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
            public delegate SQLiteErrorCode xRename(
                [MarshalAs(UnmanagedType.LPStruct)]
                IntPtr pVtab,
                IntPtr zNew
            );

            [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
            public delegate SQLiteErrorCode xSavepoint(
                [MarshalAs(UnmanagedType.LPStruct)]
                IntPtr pVtab,
                int iSavepoint
            );

            [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
            public delegate SQLiteErrorCode xRelease(
                [MarshalAs(UnmanagedType.LPStruct)]
                IntPtr pVtab,
                int iSavepoint
            );

            [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
            public delegate SQLiteErrorCode xRollbackTo(
                [MarshalAs(UnmanagedType.LPStruct)]
                IntPtr pVtab,
                int iSavepoint
            );

            private static readonly int SQLITE_INDEX_CONSTRAINT_EQ = 2;
            private static readonly int SQLITE_INDEX_CONSTRAINT_GT = 4;
            private static readonly int SQLITE_INDEX_CONSTRAINT_LE = 8;
................................................................................
        private static void Free(IntPtr pMemory)
        {
            UnsafeNativeMethods.sqlite3_free(pMemory);
        }

        ///////////////////////////////////////////////////////////////////////


















        private static int ProbeForUtf8ByteLength(IntPtr pValue, int limit)
        {
            int length = 0;

            if (pValue != IntPtr.Zero)
            {
                do
................................................................................
            }

            return length;
        }

        ///////////////////////////////////////////////////////////////////////

        private static string StringFromUtf8IntPtr(IntPtr pValue)









        {
            if (pValue == IntPtr.Zero)
                return null;

            int length = ProbeForUtf8ByteLength(pValue, ThirtyBits);

            if (length > 0)
            {
                byte[] bytes = new byte[length];

                Marshal.Copy(pValue, bytes, 0, length);

                return GetStringFromUtf8Bytes(bytes);
            }

            return String.Empty;
        }

        ///////////////////////////////////////////////////////////////////////







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namespace System.Data.SQLite
{
    public sealed class SQLiteContext
    {

    }

    ///////////////////////////////////////////////////////////////////////////

    public sealed class SQLiteValue
    {
        #region Private Data
        private IntPtr pValue;
        #endregion

        ///////////////////////////////////////////////////////////////////////

        #region Private Constructors
        internal SQLiteValue(IntPtr pValue)
        {
            this.pValue = pValue;
        }
        #endregion

        ///////////////////////////////////////////////////////////////////////

        #region Public Methods
        public TypeAffinity GetTypeAffinity()
        {
            return UnsafeNativeMethods.sqlite3_value_type(pValue);
        }

        ///////////////////////////////////////////////////////////////////////

        public int GetBytes()
        {
            return UnsafeNativeMethods.sqlite3_value_bytes(pValue);
        }

        ///////////////////////////////////////////////////////////////////////

        public int GetInt()
        {
            return UnsafeNativeMethods.sqlite3_value_int(pValue);
        }

        ///////////////////////////////////////////////////////////////////////

        public long GetInt64()
        {
            return UnsafeNativeMethods.sqlite3_value_int64(pValue);
        }

        ///////////////////////////////////////////////////////////////////////

        public double GetDouble()
        {
            return UnsafeNativeMethods.sqlite3_value_double(pValue);
        }

        ///////////////////////////////////////////////////////////////////////

        public string GetString()
        {
            return SQLiteModuleBase.StringFromUtf8IntPtr(pValue, GetBytes());
        }

        ///////////////////////////////////////////////////////////////////////

        public byte[] GetBlob()
        {
            return SQLiteModuleBase.BytesFromIntPtr(pValue, GetBytes());
        }
        #endregion
    }

    ///////////////////////////////////////////////////////////////////////////

    public class SQLiteIndexConstraint
    {
        private SQLiteModuleBase.UnsafeNativeMethods2.sqlite3_index_constraint constraint;
    }

    ///////////////////////////////////////////////////////////////////////////

    public class SQLiteIndexOrderBy
    {
        private SQLiteModuleBase.UnsafeNativeMethods2.sqlite3_index_orderby orderBy;
    }

    ///////////////////////////////////////////////////////////////////////////

    public class SQLiteIndexConstraintUsage
    {
        private SQLiteModuleBase.UnsafeNativeMethods2.sqlite3_index_constraint_usage constraintUsage;
    }

    ///////////////////////////////////////////////////////////////////////////

    public class SQLiteIndex
    {
        SQLiteIndexConstraint[] Constraints;
        SQLiteIndexOrderBy[] OrderBys;


................................................................................
        int idxNum;           /* Number used to identify the index */
        string idxStr;        /* String, possibly obtained from sqlite3_malloc */
        int needToFreeIdxStr; /* Free idxStr using sqlite3_free() if true */
        int orderByConsumed;  /* True if output is already ordered */
        double estimatedCost; /* Estimated cost of using this index */
    }

    ///////////////////////////////////////////////////////////////////////////

    public class SQLiteVirtualTableCursor
    {
        internal SQLiteModuleBase.UnsafeNativeMethods2.sqlite3_vtab_cursor cursor;
    }

    ///////////////////////////////////////////////////////////////////////////

    [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
    public delegate int xFunc(
        IntPtr pContext,
        int argc,
        [MarshalAs(UnmanagedType.LPArray, SizeParamIndex = 1)]
        IntPtr[] argv
    );

    ///////////////////////////////////////////////////////////////////////////

    public interface ISQLiteNativeModule
    {
        SQLiteErrorCode xCreate(IntPtr pDb, IntPtr pAux, int argc, ref IntPtr[] argv, ref IntPtr pVtab, ref IntPtr pError);
        SQLiteErrorCode xConnect(IntPtr pDb, IntPtr pAux, int argc, ref IntPtr[] argv, ref IntPtr pVtab, ref IntPtr pError);
        SQLiteErrorCode xBestIndex(IntPtr pVtab, IntPtr index);
        SQLiteErrorCode xDisconnect(IntPtr pVtab);
................................................................................
        SQLiteErrorCode xRollback(IntPtr pVtab);
        SQLiteErrorCode xFindFunction(IntPtr pVtab, int nArg, IntPtr zName, ref xFunc pxFunc, ref IntPtr ppArg);
        SQLiteErrorCode xRename(IntPtr pVtab, IntPtr zNew);
        SQLiteErrorCode xSavepoint(IntPtr pVtab, int iSavepoint);
        SQLiteErrorCode xRelease(IntPtr pVtab, int iSavepoint);
        SQLiteErrorCode xRollbackTo(IntPtr pVtab, int iSavepoint);
    }

    ///////////////////////////////////////////////////////////////////////////

    public interface ISQLiteManagedModule
    {
        bool Declared { get; }

        SQLiteErrorCode Create(SQLiteConnection connection, IntPtr pClientData, string[] argv, ref string error);
        SQLiteErrorCode Connect(SQLiteConnection connection, IntPtr pClientData, string[] argv, ref string error);
................................................................................
        SQLiteErrorCode Rollback();
        SQLiteErrorCode FindFunction(string zName, ref SQLiteFunction function, object[] args);
        SQLiteErrorCode Rename(string zNew);
        SQLiteErrorCode Savepoint(int iSavepoint);
        SQLiteErrorCode Release(int iSavepoint);
        SQLiteErrorCode RollbackTo(int iSavepoint);
    }

    ///////////////////////////////////////////////////////////////////////////

#if NET_40
    [SecurityCritical()]
#else
    [SecurityPermission(SecurityAction.LinkDemand, UnmanagedCode = true)]
#endif
    public abstract class SQLiteModuleBase : ISQLiteManagedModule, ISQLiteNativeModule,  IDisposable
................................................................................
                ref IntPtr[] argv,
                ref IntPtr pVtab,
                ref IntPtr pError
            );

            [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
            public delegate SQLiteErrorCode xBestIndex(

                IntPtr pVtab,

                IntPtr index
            );

            [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
            public delegate SQLiteErrorCode xDisconnect(

                IntPtr pVtab
            );

            [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
            public delegate SQLiteErrorCode xDestroy(

                IntPtr pVtab
            );

            [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
            public delegate SQLiteErrorCode xOpen(

                IntPtr pVtab,
                ref IntPtr pCursor
            );

            [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
            public delegate SQLiteErrorCode xClose(

                IntPtr pCursor
            );

            [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
            public delegate SQLiteErrorCode xFilter(

                IntPtr pCursor,
                int idxNum,
                IntPtr idxStr,
                int argc,
                IntPtr[] argv
            );

            [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
            public delegate SQLiteErrorCode xNext(

                IntPtr pCursor
            );

            [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
            public delegate SQLiteErrorCode xEof(

                IntPtr pCursor
            );

            [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
            public delegate SQLiteErrorCode xColumn(

                IntPtr pCursor,
                IntPtr pContext,
                int index
            );

            [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
            public delegate SQLiteErrorCode xRowId(

                IntPtr pCursor,
                ref long rowId
            );

            [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
            public delegate SQLiteErrorCode xUpdate(

                IntPtr pVtab,
                int nData,
                ref IntPtr apData,
                ref long rowId
            );

            [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
            public delegate SQLiteErrorCode xBegin(

                IntPtr pVtab
            );

            [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
            public delegate SQLiteErrorCode xSync(

                IntPtr pVtab
            );

            [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
            public delegate SQLiteErrorCode xCommit(

                IntPtr pVtab
            );

            [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
            public delegate SQLiteErrorCode xRollback(

                IntPtr pVtab
            );

            [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
            public delegate SQLiteErrorCode xFindFunction(

                IntPtr pVtab,
                int nArg,
                IntPtr zName,
                ref xFunc pxFunc,
                ref IntPtr ppArg
            );

            [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
            public delegate SQLiteErrorCode xRename(

                IntPtr pVtab,
                IntPtr zNew
            );

            [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
            public delegate SQLiteErrorCode xSavepoint(

                IntPtr pVtab,
                int iSavepoint
            );

            [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
            public delegate SQLiteErrorCode xRelease(

                IntPtr pVtab,
                int iSavepoint
            );

            [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
            public delegate SQLiteErrorCode xRollbackTo(

                IntPtr pVtab,
                int iSavepoint
            );

            private static readonly int SQLITE_INDEX_CONSTRAINT_EQ = 2;
            private static readonly int SQLITE_INDEX_CONSTRAINT_GT = 4;
            private static readonly int SQLITE_INDEX_CONSTRAINT_LE = 8;
................................................................................
        private static void Free(IntPtr pMemory)
        {
            UnsafeNativeMethods.sqlite3_free(pMemory);
        }

        ///////////////////////////////////////////////////////////////////////

        internal static byte[] BytesFromIntPtr(IntPtr pValue, int length)
        {
            if (pValue == IntPtr.Zero)
                return null;

            if (length == 0)
                return new byte[0];

            byte[] result = new byte[length];

            Marshal.Copy(pValue, result, 0, length);

            return result;
        }

        ///////////////////////////////////////////////////////////////////////

        private static int ProbeForUtf8ByteLength(IntPtr pValue, int limit)
        {
            int length = 0;

            if (pValue != IntPtr.Zero)
            {
                do
................................................................................
            }

            return length;
        }

        ///////////////////////////////////////////////////////////////////////

        internal static string StringFromUtf8IntPtr(IntPtr pValue)
        {
            int length = ProbeForUtf8ByteLength(pValue, ThirtyBits);

            return StringFromUtf8IntPtr(pValue, length);
        }

        ///////////////////////////////////////////////////////////////////////

        internal static string StringFromUtf8IntPtr(IntPtr pValue, int length)
        {
            if (pValue == IntPtr.Zero)
                return null;



            if (length > 0)
            {
                byte[] bytes = new byte[length];

                Marshal.Copy(pValue, bytes, 0, length);

                return GetStringFromUtf8Bytes(bytes);
            }

            return String.Empty;
        }

        ///////////////////////////////////////////////////////////////////////