System.Data.SQLite

    private static event SQLiteConnectionEventHandler _handlers;

    /// <summary>
    /// The extra connection flags to be used for all opened connections.
    /// </summary>
    private static SQLiteConnectionFlags _sharedFlags;

    /// <summary>
    /// The <see cref="SQLiteConnection" /> instance (for this thread) that
    /// had the most recent call to <see cref="SQLiteConnection.Open" />.
    /// </summary>
#if !PLATFORM_COMPACTFRAMEWORK
    [ThreadStatic()]
#endif
    private static SQLiteConnection _lastConnectionInOpen;

#if SQLITE_STANDARD && !PLATFORM_COMPACTFRAMEWORK
    /// <summary>
    /// Used to hold the active library version number of SQLite.
    /// </summary>
    private static int _versionNumber;
#endif
    #endregion

    /// the value of <paramref name="default" /> is stored here.
    /// </param>
    /// <returns>
    /// Non-zero if the cached setting was found; otherwise, zero.
    /// </returns>
    internal bool TryGetCachedSetting(
        string name,     /* in */
        string @default, /* in */
        object @default, /* in */
        out object value /* out */
        )
    {
        if ((name == null) || (_cachedSettings == null))
        {
            value = @default;
            return false;

    /// within the connection string.
    /// </returns>
    internal static SortedList<string, string> ParseConnectionString(
        string connectionString,
        bool parseViaFramework,
        bool allowNameOnly
        )
    {
        return ParseConnectionString(
            null, connectionString, parseViaFramework, allowNameOnly);
    }

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

    /// <summary>
    /// Parses a connection string into component parts using the custom
    /// connection string parser.  An exception may be thrown if the syntax
    /// of the connection string is incorrect.
    /// </summary>
    /// <param name="connection">
    /// The connection that will be using the parsed connection string.
    /// </param>
    /// <param name="connectionString">
    /// The connection string to parse.
    /// </param>
    /// <param name="parseViaFramework">
    /// Non-zero to parse the connection string using the algorithm provided
    /// by the framework itself.  This is not applicable when running on the
    /// .NET Compact Framework.
    /// </param>
    /// <param name="allowNameOnly">
    /// Non-zero if names are allowed without values.
    /// </param>
    /// <returns>
    /// The list of key/value pairs corresponding to the parameters specified
    /// within the connection string.
    /// </returns>
    private static SortedList<string, string> ParseConnectionString(
        SQLiteConnection connection,
        string connectionString,
        bool parseViaFramework,
        bool allowNameOnly
        )
    {
        return parseViaFramework ?
            ParseConnectionStringViaFramework(connectionString, false) :
            ParseConnectionString(connectionString, allowNameOnly);
            ParseConnectionStringViaFramework(connection, connectionString, false) :
            ParseConnectionString(connection, connectionString, allowNameOnly);
    }

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

    private void SetupSQLiteBase(SortedList<string, string> opts)
    {
        object enumValue;

      else if (path.StartsWith ("file:", StringComparison.OrdinalIgnoreCase))
            return path.Substring (5);
      else if (path.StartsWith ("/", StringComparison.OrdinalIgnoreCase))
            return path;
      else
            throw new InvalidOperationException ("Invalid connection string: invalid URI");
    }

    /// <summary>
    /// Determines if the legacy connection string parser should be used.
    /// </summary>
    /// <param name="connection">
    /// The connection that will be using the parsed connection string.
    /// </param>
    /// <returns>
    /// Non-zero if the legacy connection string parser should be used.
    /// </returns>
    private static bool ShouldUseLegacyConnectionStringParser(
        SQLiteConnection connection
        )
    {
        string name = "No_SQLiteConnectionNewParser";
        object value; /* NOT USED */

        if ((connection != null) &&
            connection.TryGetCachedSetting(name, null, out value))
        {
            return true;
        }

        if ((connection == null) &&
            TryGetLastCachedSetting(name, null, out value))
        {
            return true;
        }

        return (UnsafeNativeMethods.GetSettingValue(name, null) != null);
    }

    /// <summary>
    /// Parses a connection string into component parts using the custom
    /// connection string parser.  An exception may be thrown if the syntax
    /// of the connection string is incorrect.
    /// </summary>
    /// <param name="connectionString">
    /// The connection string to parse.
    /// </param>
    /// <param name="allowNameOnly">
    /// Non-zero if names are allowed without values.
    /// </param>
    /// <returns>
    /// The list of key/value pairs corresponding to the parameters specified
    /// within the connection string.
    /// </returns>
    private static SortedList<string, string> ParseConnectionString(
        string connectionString,
        bool allowNameOnly
        )
    {
        return ParseConnectionString(null, connectionString, allowNameOnly);
    }

    /// <summary>
    /// Parses a connection string into component parts using the custom
    /// connection string parser.  An exception may be thrown if the syntax
    /// of the connection string is incorrect.
    /// </summary>
    /// <param name="connection">
    /// The connection that will be using the parsed connection string.
    /// </param>
    /// <param name="connectionString">
    /// The connection string to parse.
    /// </param>
    /// <param name="allowNameOnly">
    /// Non-zero if names are allowed without values.
    /// </param>
    /// <returns>
    /// The list of key/value pairs corresponding to the parameters specified
    /// within the connection string.
    /// </returns>
    private static SortedList<string, string> ParseConnectionString(
        SQLiteConnection connection,
        string connectionString,
        bool allowNameOnly
        )
    {
      string s = connectionString;
      int n;
      SortedList<string, string> ls = new SortedList<string, string>(StringComparer.OrdinalIgnoreCase);

      // First split into semi-colon delimited values.
      string error = null;
      string[] arParts;

      if (UnsafeNativeMethods.GetSettingValue("No_SQLiteConnectionNewParser", null) != null)
      if (ShouldUseLegacyConnectionStringParser(connection))
          arParts = SQLiteConvert.Split(s, ';');
      else
          arParts = SQLiteConvert.NewSplit(s, ';', true, ref error);

      if (arParts == null)
      {
          throw new ArgumentException(HelperMethods.StringFormat(

    /// Parses a connection string using the built-in (i.e. framework provided)
    /// connection string parser class and returns the key/value pairs.  An
    /// exception may be thrown if the connection string is invalid or cannot be
    /// parsed.  When compiled for the .NET Compact Framework, the custom
    /// connection string parser is always used instead because the framework
    /// provided one is unavailable there.
    /// </summary>
    /// <param name="connection">
    /// The connection that will be using the parsed connection string.
    /// </param>
    /// <param name="connectionString">
    /// The connection string to parse.
    /// </param>
    /// <param name="strict">
    /// Non-zero to throw an exception if any connection string values are not of
    /// the <see cref="String" /> type.  This is not applicable when running on
    /// the .NET Compact Framework.
    /// </param>
    /// <returns>The list of key/value pairs.</returns>
    private static SortedList<string, string> ParseConnectionStringViaFramework(
        SQLiteConnection connection,
        string connectionString,
        bool strict
        )
    {
#if !PLATFORM_COMPACTFRAMEWORK
        DbConnectionStringBuilder connectionStringBuilder
            = new DbConnectionStringBuilder();

        return result;
#else
        //
        // NOTE: On the .NET Compact Framework, always use our custom connection
        //       string parser as the built-in (i.e. framework provided) one is
        //       unavailable.
        //
        return ParseConnectionString(connectionString, false);
        return ParseConnectionString(connection, connectionString, false);
#endif
    }

#if !PLATFORM_COMPACTFRAMEWORK
    /// <summary>
    /// Manual distributed transaction enlistment support
    /// </summary>

    /// <summary>
    /// Opens the connection using the parameters found in the <see cref="ConnectionString" />.
    /// </summary>
    public override void Open()
    {
      CheckDisposed();

      _lastConnectionInOpen = this; /* THREAD-SAFE: per-thread datum. */

      OnChanged(this, new ConnectionEventArgs(
          SQLiteConnectionEventType.Opening, null, null, null, null, null,
          null, null));

      if (_connectionState != ConnectionState.Closed)
        throw new InvalidOperationException();

      Close();

      SortedList<string, string> opts = ParseConnectionString(
          _connectionString, _parseViaFramework, false);
          this, _connectionString, _parseViaFramework, false);

      OnChanged(this, new ConnectionEventArgs(
          SQLiteConnectionEventType.ConnectionString, null, null, null, null,
          null, _connectionString, new object[] { opts }));

      object enumValue;

            }
            else
            {
                return null;
            }
        }
    }

    /// <summary>
    /// Queries and returns the value of the specified setting, using the
    /// cached setting names and values for the last connection that used
    /// by the <see cref="SQLiteConnection.Open" /> method, when available.
    /// </summary>
    /// <param name="name">
    /// The name of the setting.
    /// </param>
    /// <param name="default">
    /// The value to be returned if the setting has not been set explicitly
    /// or cannot be determined.
    /// </param>
    /// <param name="value">
    /// The value of the cached setting is stored here if found; otherwise,
    /// the value of <paramref name="default" /> is stored here.
    /// </param>
    /// <returns>
    /// Non-zero if the cached setting was found; otherwise, zero.
    /// </returns>
    private static bool TryGetLastCachedSetting(
        string name,
        object @default,
        out object value
        )
    {
        if (_lastConnectionInOpen == null)
        {
            value = @default;
            return false;
        }

        return _lastConnectionInOpen.TryGetCachedSetting(
            name, @default, out value);
    }

    /// <summary>
    /// The default connection flags to be used for all opened connections
    /// when they are not present in the connection string.
    /// </summary>
    public static SQLiteConnectionFlags DefaultFlags
    {
        get
        {
            string name = "DefaultFlags_SQLiteConnection";
            object enumValue;
            object value;

            enumValue = TryParseEnum(typeof(SQLiteConnectionFlags),
                UnsafeNativeMethods.GetSettingValue(
                    "DefaultFlags_SQLiteConnection", null), true);
            if (!TryGetLastCachedSetting(name, null, out value))
                value = UnsafeNativeMethods.GetSettingValue(name, null);

            if (value == null)
                return FallbackDefaultFlags;

            object enumValue = TryParseEnum(
                typeof(SQLiteConnectionFlags), value.ToString(), true);

            if (enumValue is SQLiteConnectionFlags)
                return (SQLiteConnectionFlags)enumValue;

            return FallbackDefaultFlags;
        }
    }