Changed layout to support tagging and branching

12 files changed, 2534 insertions, 0 deletions

diff --git a/lib/sqlite3/constants.rb b/lib/sqlite3/constants.rb
new file mode 100644
index 0000000..5a20e46
--- /dev/null
+++ b/lib/sqlite3/constants.rb
@@ -0,0 +1,81 @@
+#--
+# =============================================================================
+# Copyright (c) 2004, Jamis Buck (jgb3@email.byu.edu)
+# All rights reserved.
+# 
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are met:
+# 
+#     * Redistributions of source code must retain the above copyright notice,
+#       this list of conditions and the following disclaimer.
+# 
+#     * Redistributions in binary form must reproduce the above copyright
+#       notice, this list of conditions and the following disclaimer in the
+#       documentation and/or other materials provided with the distribution.
+# 
+#     * The names of its contributors may not be used to endorse or promote
+#       products derived from this software without specific prior written
+#       permission.
+# 
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+# DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE
+# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+# SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+# CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+# OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+# =============================================================================
+#++
+
+module SQLite3 ; module Constants
+
+  module TextRep
+    UTF8    = 1
+    UTF16LE = 2
+    UTF16BE = 3
+    UTF16   = 4
+    ANY     = 5
+  end
+
+  module ColumnType
+    INTEGER = 1
+    FLOAT   = 2
+    TEXT    = 3
+    BLOB    = 4
+    NULL    = 5
+  end
+
+  module ErrorCode
+    OK         =  0   # Successful result
+    ERROR      =  1   # SQL error or missing database
+    INTERNAL   =  2   # An internal logic error in SQLite
+    PERM       =  3   # Access permission denied
+    ABORT      =  4   # Callback routine requested an abort
+    BUSY       =  5   # The database file is locked
+    LOCKED     =  6   # A table in the database is locked
+    NOMEM      =  7   # A malloc() failed
+    READONLY   =  8   # Attempt to write a readonly database
+    INTERRUPT  =  9   # Operation terminated by sqlite_interrupt()
+    IOERR      = 10   # Some kind of disk I/O error occurred
+    CORRUPT    = 11   # The database disk image is malformed
+    NOTFOUND   = 12   # (Internal Only) Table or record not found
+    FULL       = 13   # Insertion failed because database is full
+    CANTOPEN   = 14   # Unable to open the database file
+    PROTOCOL   = 15   # Database lock protocol error
+    EMPTY      = 16   # (Internal Only) Database table is empty
+    SCHEMA     = 17   # The database schema changed
+    TOOBIG     = 18   # Too much data for one row of a table
+    CONSTRAINT = 19   # Abort due to contraint violation
+    MISMATCH   = 20   # Data type mismatch
+    MISUSE     = 21   # Library used incorrectly
+    NOLFS      = 22   # Uses OS features not supported on host
+    AUTH       = 23   # Authorization denied
+
+    ROW        = 100  # sqlite_step() has another row ready
+    DONE       = 101  # sqlite_step() has finished executing
+  end
+
+end ; end
diff --git a/lib/sqlite3/database.rb b/lib/sqlite3/database.rb
new file mode 100644
index 0000000..65a8410
--- /dev/null
+++ b/lib/sqlite3/database.rb
@@ -0,0 +1,720 @@
+#--
+# =============================================================================
+# Copyright (c) 2004, Jamis Buck (jgb3@email.byu.edu)
+# All rights reserved.
+# 
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are met:
+# 
+#     * Redistributions of source code must retain the above copyright notice,
+#       this list of conditions and the following disclaimer.
+# 
+#     * Redistributions in binary form must reproduce the above copyright
+#       notice, this list of conditions and the following disclaimer in the
+#       documentation and/or other materials provided with the distribution.
+# 
+#     * The names of its contributors may not be used to endorse or promote
+#       products derived from this software without specific prior written
+#       permission.
+# 
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+# DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE
+# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+# SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+# CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+# OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+# =============================================================================
+#++
+
+require 'base64'
+require 'sqlite3/constants'
+require 'sqlite3/errors'
+require 'sqlite3/pragmas'
+require 'sqlite3/statement'
+require 'sqlite3/translator'
+require 'sqlite3/value'
+
+module SQLite3
+
+  # The Database class encapsulates a single connection to a SQLite3 database.
+  # Its usage is very straightforward:
+  #
+  #   require 'sqlite3'
+  #
+  #   db = SQLite3::Database.new( "data.db" )
+  #
+  #   db.execute( "select * from table" ) do |row|
+  #     p row
+  #   end
+  #
+  #   db.close
+  #
+  # It wraps the lower-level methods provides by the selected driver, and
+  # includes the Pragmas module for access to various pragma convenience
+  # methods.
+  #
+  # The Database class provides type translation services as well, by which
+  # the SQLite3 data types (which are all represented as strings) may be
+  # converted into their corresponding types (as defined in the schemas
+  # for their tables). This translation only occurs when querying data from
+  # the database--insertions and updates are all still typeless.
+  #
+  # Furthermore, the Database class has been designed to work well with the
+  # ArrayFields module from Ara Howard. If you require the ArrayFields
+  # module before performing a query, and if you have not enabled results as
+  # hashes, then the results will all be indexible by field name.
+  class Database
+    include Pragmas
+
+    class <<self
+
+      alias :open :new
+
+      # Quotes the given string, making it safe to use in an SQL statement.
+      # It replaces all instances of the single-quote character with two
+      # single-quote characters. The modified string is returned.
+      def quote( string )
+        string.gsub( /'/, "''" )
+      end
+
+    end
+
+    # The low-level opaque database handle that this object wraps.
+    attr_reader :handle
+
+    # A reference to the underlying SQLite3 driver used by this database.
+    attr_reader :driver
+
+    # A boolean that indicates whether rows in result sets should be returned
+    # as hashes or not. By default, rows are returned as arrays.
+    attr_accessor :results_as_hash
+
+    # A boolean indicating whether or not type translation is enabled for this
+    # database.
+    attr_accessor :type_translation
+
+    # Create a new Database object that opens the given file. If utf16
+    # is +true+, the filename is interpreted as a UTF-16 encoded string.
+    #
+    # By default, the new database will return result rows as arrays
+    # (#results_as_hash) and has type translation disabled (#type_translation=).
+    def initialize( file_name, options={} )
+      utf16 = options.fetch(:utf16, false)
+      load_driver( options[:driver] )
+
+      @statement_factory = options[:statement_factory] || Statement
+
+      result, @handle = @driver.open( file_name, utf16 )
+      Error.check( result, nil, "could not open database" )
+
+      @closed = false
+      @results_as_hash = options.fetch(:results_as_hash,false)
+      @type_translation = options.fetch(:type_translation,false)
+      @translator = nil
+    end
+
+    # Return +true+ if the string is a valid (ie, parsable) SQL statement, and
+    # +false+ otherwise. If +utf16+ is +true+, then the string is a UTF-16
+    # character string.
+    def complete?( string, utf16=false )
+      @driver.complete?( string, utf16 )
+    end
+
+    # Return a string describing the last error to have occurred with this
+    # database.
+    def errmsg( utf16=false )
+      @driver.errmsg( @handle, utf16 )
+    end
+
+    # Return an integer representing the last error to have occurred with this
+    # database.
+    def errcode
+      @driver.errcode( @handle )
+    end
+
+    # Return the type translator employed by this database instance. Each
+    # database instance has its own type translator; this allows for different
+    # type handlers to be installed in each instance without affecting other
+    # instances. Furthermore, the translators are instantiated lazily, so that
+    # if a database does not use type translation, it will not be burdened by
+    # the overhead of a useless type translator. (See the Translator class.)
+    def translator
+      @translator ||= Translator.new
+    end
+
+    # Closes this database.
+    def close
+      unless @closed
+        result = @driver.close( @handle )
+        Error.check( result, self )
+      end
+      @closed = true
+    end
+
+    # Returns +true+ if this database instance has been closed (see #close).
+    def closed?
+      @closed
+    end
+
+    # Installs (or removes) a block that will be invoked for every SQL
+    # statement executed. The block receives a two parameters: the +data+
+    # argument, and the SQL statement executed. If the block is +nil+,
+    # any existing tracer will be uninstalled.
+    def trace( data=nil, &block )
+      @driver.trace( @handle, data, &block )
+    end
+
+    # Installs (or removes) a block that will be invoked for every access
+    # to the database. If the block returns 0 (or +nil+), the statement
+    # is allowed to proceed. Returning 1 causes an authorization error to
+    # occur, and returning 2 causes the access to be silently denied.
+    def authorizer( data=nil, &block )
+      result = @driver.set_authorizer( @handle, data, &block )
+      Error.check( result, self )
+    end
+
+    # Returns a Statement object representing the given SQL. This does not
+    # execute the statement; it merely prepares the statement for execution.
+    def prepare( sql )
+      stmt = @statement_factory.new( self, sql )
+      if block_given?
+        begin
+          yield stmt
+        ensure
+          stmt.close
+        end
+      else
+        return stmt
+      end
+    end
+
+    # Executes the given SQL statement. If additional parameters are given,
+    # they are treated as bind variables, and are bound to the placeholders in
+    # the query.
+    #
+    # Note that if any of the values passed to this are hashes, then the
+    # key/value pairs are each bound separately, with the key being used as
+    # the name of the placeholder to bind the value to.
+    #
+    # The block is optional. If given, it will be invoked for each row returned
+    # by the query. Otherwise, any results are accumulated into an array and
+    # returned wholesale.
+    #
+    # See also #execute2, and #execute_batch for additional ways of
+    # executing statements.
+    def execute( sql, *bind_vars )
+      prepare( sql ) do |stmt|
+        result = stmt.execute( *bind_vars )
+        if block_given?
+          result.each { |row| yield row }
+        else
+          return result.inject( [] ) { |arr,row| arr << row; arr }
+        end
+      end
+    end
+
+    # Executes the given SQL statement, exactly as with #execute. However, the
+    # first row returned (either via the block, or in the returned array) is
+    # always the names of the columns. Subsequent rows correspond to the data
+    # from the result set.
+    #
+    # Thus, even if the query itself returns no rows, this method will always
+    # return at least one row--the names of the columns.
+    #
+    # See also #execute, and #execute_batch for additional ways of
+    # executing statements.
+    def execute2( sql, *bind_vars )
+      prepare( sql ) do |stmt|
+        result = stmt.execute( *bind_vars )
+        if block_given?
+          yield result.columns
+          result.each { |row| yield row }
+        else
+          return result.inject( [ result.columns ] ) { |arr,row|
+            arr << row; arr }
+        end
+      end
+    end
+
+    # Executes all SQL statements in the given string. By contrast, the other
+    # means of executing queries will only execute the first statement in the
+    # string, ignoring all subsequent statements. This will execute each one
+    # in turn. The same bind parameters, if given, will be applied to each
+    # statement.
+    #
+    # This always returns +nil+, making it unsuitable for queries that return
+    # rows.
+    def execute_batch( sql, *bind_vars )
+      sql = sql.strip
+      until sql.empty? do
+        prepare( sql ) do |stmt|
+          stmt.execute( *bind_vars )
+          sql = stmt.remainder.strip
+        end
+      end
+      nil
+    end
+
+    # A convenience method for obtaining the first row of a result set, and
+    # discarding all others. It is otherwise identical to #execute.
+    #
+    # See also #get_first_value.
+    def get_first_row( sql, *bind_vars )
+      execute( sql, *bind_vars ) { |row| return row }
+      nil
+    end
+
+    # A convenience method for obtaining the first value of the first row of a
+    # result set, and discarding all other values and rows. It is otherwise
+    # identical to #execute.
+    #
+    # See also #get_first_row.
+    def get_first_value( sql, *bind_vars )
+      execute( sql, *bind_vars ) { |row| return row[0] }
+      nil
+    end
+
+    # Obtains the unique row ID of the last row to be inserted by this Database
+    # instance.
+    def last_insert_row_id
+      @driver.last_insert_rowid( @handle )
+    end
+
+    # Returns the number of changes made to this database instance by the last
+    # operation performed. Note that a "delete from table" without a where
+    # clause will not affect this value.
+    def changes
+      @driver.changes( @handle )
+    end
+
+    # Returns the total number of changes made to this database instance
+    # since it was opened.
+    def total_changes
+      @driver.total_changes( @handle )
+    end
+
+    # Interrupts the currently executing operation, causing it to abort.
+    def interrupt
+      @driver.interrupt( @handle )
+    end
+
+    # Register a busy handler with this database instance. When a requested
+    # resource is busy, this handler will be invoked. If the handler returns
+    # +false+, the operation will be aborted; otherwise, the resource will
+    # be requested again.
+    #
+    # The handler will be invoked with the name of the resource that was
+    # busy, and the number of times it has been retried.
+    #
+    # See also #busy_timeout.
+    def busy_handler( data=nil, &block ) # :yields: data, retries
+      result = @driver.busy_handler( @handle, data, &block )
+      Error.check( result, self )
+    end
+
+    # Indicates that if a request for a resource terminates because that
+    # resource is busy, SQLite should wait for the indicated number of
+    # milliseconds before trying again. By default, SQLite does not retry
+    # busy resources. To restore the default behavior, send 0 as the
+    # +ms+ parameter.
+    #
+    # See also #busy_handler.
+    def busy_timeout( ms )
+      result = @driver.busy_timeout( @handle, ms )
+      Error.check( result, self )
+    end
+
+    # Creates a new function for use in SQL statements. It will be added as
+    # +name+, with the given +arity+. (For variable arity functions, use
+    # -1 for the arity.)
+    #
+    # The block should accept at least one parameter--the FunctionProxy
+    # instance that wraps this function invocation--and any other
+    # arguments it needs (up to its arity).
+    #
+    # The block does not return a value directly. Instead, it will invoke
+    # the FunctionProxy#set_result method on the +func+ parameter and
+    # indicate the return value that way.
+    #
+    # Example:
+    #
+    #   db.create_function( "maim", 1 ) do |func, value|
+    #     if value.nil?
+    #       func.result = nil
+    #     else
+    #       func.result = value.split(//).sort.join
+    #     end
+    #   end
+    #
+    #   puts db.get_first_value( "select maim(name) from table" )
+    def create_function( name, arity, text_rep=Constants::TextRep::ANY,
+      &block ) # :yields: func, *args
+    # begin
+      callback = proc do |func,*args|
+        begin
+          block.call( FunctionProxy.new( @driver, func ),
+            *args.map{|v| Value.new(self,v)} )
+        rescue StandardError, Exception => e
+          @driver.result_error( func,
+            "#{e.message} (#{e.class})", -1 )
+        end
+      end
+
+      result = @driver.create_function( @handle, name, arity, text_rep, nil,
+        callback, nil, nil )
+      Error.check( result, self )
+
+      self
+    end
+
+    # Creates a new aggregate function for use in SQL statements. Aggregate
+    # functions are functions that apply over every row in the result set,
+    # instead of over just a single row. (A very common aggregate function
+    # is the "count" function, for determining the number of rows that match
+    # a query.)
+    #
+    # The new function will be added as +name+, with the given +arity+. (For
+    # variable arity functions, use -1 for the arity.)
+    #
+    # The +step+ parameter must be a proc object that accepts as its first
+    # parameter a FunctionProxy instance (representing the function
+    # invocation), with any subsequent parameters (up to the function's arity).
+    # The +step+ callback will be invoked once for each row of the result set.
+    #
+    # The +finalize+ parameter must be a +proc+ object that accepts only a
+    # single parameter, the FunctionProxy instance representing the current
+    # function invocation. It should invoke FunctionProxy#set_result to
+    # store the result of the function.
+    #
+    # Example:
+    #
+    #   db.create_aggregate( "lengths", 1 ) do
+    #     step do |func, value|
+    #       func[ :total ] ||= 0
+    #       func[ :total ] += ( value ? value.length : 0 )
+    #     end
+    #
+    #     finalize do |func|
+    #       func.set_result( func[ :total ] || 0 )
+    #     end
+    #   end
+    #
+    #   puts db.get_first_value( "select lengths(name) from table" )
+    #
+    # See also #create_aggregate_handler for a more object-oriented approach to
+    # aggregate functions.
+    def create_aggregate( name, arity, step=nil, finalize=nil,
+      text_rep=Constants::TextRep::ANY, &block )
+    # begin
+      if block
+        proxy = AggregateDefinitionProxy.new
+        proxy.instance_eval &block
+        step ||= proxy.step_callback
+        finalize ||= proxy.finalize_callback
+      end
+
+      step_callback = proc do |func,*args|
+        ctx = @driver.aggregate_context( func )
+        unless ctx[:__error]
+          begin
+            step.call( FunctionProxy.new( @driver, func, ctx ),
+              *args.map{|v| Value.new(self,v)} )
+          rescue Exception => e
+            ctx[:__error] = e
+          end
+        end
+      end
+
+      finalize_callback = proc do |func|
+        ctx = @driver.aggregate_context( func )
+        unless ctx[:__error]
+          begin
+            finalize.call( FunctionProxy.new( @driver, func, ctx ) )
+          rescue Exception => e
+            @driver.result_error( func,
+              "#{e.message} (#{e.class})", -1 )
+          end
+        else
+          e = ctx[:__error]
+          @driver.result_error( func,
+            "#{e.message} (#{e.class})", -1 )
+        end
+      end
+
+      result = @driver.create_function( @handle, name, arity, text_rep, nil,
+        nil, step_callback, finalize_callback )
+      Error.check( result, self )
+
+      self
+    end
+
+    # This is another approach to creating an aggregate function (see
+    # #create_aggregate). Instead of explicitly specifying the name,
+    # callbacks, arity, and type, you specify a factory object
+    # (the "handler") that knows how to obtain all of that information. The
+    # handler should respond to the following messages:
+    #
+    # +arity+:: corresponds to the +arity+ parameter of #create_aggregate. This
+    #           message is optional, and if the handler does not respond to it,
+    #           the function will have an arity of -1.
+    # +name+:: this is the name of the function. The handler _must_ implement
+    #          this message.
+    # +new+:: this must be implemented by the handler. It should return a new
+    #         instance of the object that will handle a specific invocation of
+    #         the function.
+    #
+    # The handler instance (the object returned by the +new+ message, described
+    # above), must respond to the following messages:
+    #
+    # +step+:: this is the method that will be called for each step of the
+    #          aggregate function's evaluation. It should implement the same
+    #          signature as the +step+ callback for #create_aggregate.
+    # +finalize+:: this is the method that will be called to finalize the
+    #              aggregate function's evaluation. It should implement the
+    #              same signature as the +finalize+ callback for
+    #              #create_aggregate.
+    #
+    # Example:
+    #
+    #   class LengthsAggregateHandler
+    #     def self.arity; 1; end
+    #
+    #     def initialize
+    #       @total = 0
+    #     end
+    #
+    #     def step( ctx, name )
+    #       @total += ( name ? name.length : 0 )
+    #     end
+    #
+    #     def finalize( ctx )
+    #       ctx.set_result( @total )
+    #     end
+    #   end
+    #
+    #   db.create_aggregate_handler( LengthsAggregateHandler )
+    #   puts db.get_first_value( "select lengths(name) from A" )
+    def create_aggregate_handler( handler )
+      arity = -1
+      text_rep = Constants::TextRep::ANY
+
+      arity = handler.arity if handler.respond_to?(:arity)
+      text_rep = handler.text_rep if handler.respond_to?(:text_rep)
+      name = handler.name
+
+      step = proc do |func,*args|
+        ctx = @driver.aggregate_context( func )
+        unless ctx[ :__error ]
+          ctx[ :handler ] ||= handler.new
+          begin
+            ctx[ :handler ].step( FunctionProxy.new( @driver, func, ctx ),
+              *args.map{|v| Value.new(self,v)} )
+          rescue Exception, StandardError => e
+            ctx[ :__error ] = e
+          end
+        end
+      end
+
+      finalize = proc do |func|
+        ctx = @driver.aggregate_context( func )
+        unless ctx[ :__error ]
+          ctx[ :handler ] ||= handler.new
+          begin
+            ctx[ :handler ].finalize( FunctionProxy.new( @driver, func, ctx ) )
+          rescue Exception => e
+            ctx[ :__error ] = e
+          end
+        end
+
+        if ctx[ :__error ]
+          e = ctx[ :__error ]
+          @driver.sqlite3_result_error( func, "#{e.message} (#{e.class})", -1 )
+        end
+      end
+
+      result = @driver.create_function( @handle, name, arity, text_rep, nil,
+        nil, step, finalize )
+      Error.check( result, self )
+
+      self
+    end
+
+    # Begins a new transaction. Note that nested transactions are not allowed
+    # by SQLite, so attempting to nest a transaction will result in a runtime
+    # exception.
+    #
+    # The +mode+ parameter may be either <tt>:deferred</tt> (the default),
+    # <tt>:immediate</tt>, or <tt>:exclusive</tt>.
+    #
+    # If a block is given, the database instance is yielded to it, and the
+    # transaction is committed when the block terminates. If the block
+    # raises an exception, a rollback will be performed instead. Note that if
+    # a block is given, #commit and #rollback should never be called
+    # explicitly or you'll get an error when the block terminates.
+    #
+    # If a block is not given, it is the caller's responsibility to end the
+    # transaction explicitly, either by calling #commit, or by calling
+    # #rollback.
+    def transaction( mode = :deferred )
+      execute "begin #{mode.to_s} transaction"
+      @transaction_active = true
+
+      if block_given?
+        abort = false
+        begin
+          yield self
+        rescue Exception
+          abort = true
+          raise
+        ensure
+          abort and rollback or commit
+        end
+      end
+
+      true
+    end
+
+    # Commits the current transaction. If there is no current transaction,
+    # this will cause an error to be raised. This returns +true+, in order
+    # to allow it to be used in idioms like
+    # <tt>abort? and rollback or commit</tt>.
+    def commit
+      execute "commit transaction"
+      @transaction_active = false
+      true
+    end
+
+    # Rolls the current transaction back. If there is no current transaction,
+    # this will cause an error to be raised. This returns +true+, in order
+    # to allow it to be used in idioms like
+    # <tt>abort? and rollback or commit</tt>.
+    def rollback
+      execute "rollback transaction"
+      @transaction_active = false
+      true
+    end
+
+    # Returns +true+ if there is a transaction active, and +false+ otherwise.
+    def transaction_active?
+      @transaction_active
+    end
+
+    # Loads the corresponding driver, or if it is nil, attempts to locate a
+    # suitable driver.
+    def load_driver( driver )
+      case driver
+        when Class
+          # do nothing--use what was given
+        when Symbol, String
+          require "sqlite3/driver/#{driver.to_s.downcase}/driver"
+          driver = SQLite3::Driver.const_get( driver )::Driver
+        else
+          [ "Native", "DL" ].each do |d|
+            begin
+              require "sqlite3/driver/#{d.downcase}/driver"
+              driver = SQLite3::Driver.const_get( d )::Driver
+              break
+            rescue SyntaxError
+              raise
+            rescue ScriptError, Exception
+            end
+          end
+          raise "no driver for sqlite3 found" unless driver
+      end
+
+      @driver = driver.new
+    end
+    private :load_driver
+
+    # A helper class for dealing with custom functions (see #create_function,
+    # #create_aggregate, and #create_aggregate_handler). It encapsulates the
+    # opaque function object that represents the current invocation. It also
+    # provides more convenient access to the API functions that operate on
+    # the function object.
+    #
+    # This class will almost _always_ be instantiated indirectly, by working
+    # with the create methods mentioned above.
+    class FunctionProxy
+
+      # Create a new FunctionProxy that encapsulates the given +func+ object.
+      # If context is non-nil, the functions context will be set to that. If
+      # it is non-nil, it must quack like a Hash. If it is nil, then none of
+      # the context functions will be available.
+      def initialize( driver, func, context=nil )
+        @driver = driver
+        @func = func
+        @context = context
+      end
+
+      # Calls #set_result to set the result of this function.
+      def result=( result )
+        set_result( result )
+      end
+
+      # Set the result of the function to the given value. The function will
+      # then return this value.
+      def set_result( result, utf16=false )
+        @driver.result_text( @func, result, utf16 )
+      end
+
+      # Set the result of the function to the given error message.
+      # The function will then return that error.
+      def set_error( error )
+        @driver.result_error( @func, error.to_s, -1 )
+      end
+
+      # (Only available to aggregate functions.) Returns the number of rows
+      # that the aggregate has processed so far. This will include the current
+      # row, and so will always return at least 1.
+      def count
+        ensure_aggregate!
+        @driver.aggregate_count( @func )
+      end
+
+      # Returns the value with the given key from the context. This is only
+      # available to aggregate functions.
+      def []( key )
+        ensure_aggregate!
+        @context[ key ]
+      end
+
+      # Sets the value with the given key in the context. This is only
+      # available to aggregate functions.
+      def []=( key, value )
+        ensure_aggregate!
+        @context[ key ] = value
+      end
+
+      # A function for performing a sanity check, to ensure that the function
+      # being invoked is an aggregate function. This is implied by the
+      # existence of the context variable.
+      def ensure_aggregate!
+        unless @context
+          raise MisuseException, "function is not an aggregate"
+        end
+      end
+      private :ensure_aggregate!
+
+    end
+
+    # A proxy used for defining the callbacks to an aggregate function.
+    class AggregateDefinitionProxy # :nodoc:
+      attr_reader :step_callback, :finalize_callback
+
+      def step( &block )
+        @step_callback = block
+      end
+
+      def finalize( &block )
+        @finalize_callback = block
+      end
+    end
+
+  end
+
+end
+
diff --git a/lib/sqlite3/driver/dl/api.rb b/lib/sqlite3/driver/dl/api.rb
new file mode 100644
index 0000000..f892013
--- /dev/null
+++ b/lib/sqlite3/driver/dl/api.rb
@@ -0,0 +1,184 @@
+#--
+# =============================================================================
+# Copyright (c) 2004, Jamis Buck (jgb3@email.byu.edu)
+# All rights reserved.
+# 
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are met:
+# 
+#     * Redistributions of source code must retain the above copyright notice,
+#       this list of conditions and the following disclaimer.
+# 
+#     * Redistributions in binary form must reproduce the above copyright
+#       notice, this list of conditions and the following disclaimer in the
+#       documentation and/or other materials provided with the distribution.
+# 
+#     * The names of its contributors may not be used to endorse or promote
+#       products derived from this software without specific prior written
+#       permission.
+# 
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+# DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE
+# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+# SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+# CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+# OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+# =============================================================================
+#++
+
+require 'dl/import'
+
+module SQLite3 ; module Driver; module DL;
+
+  module API
+    extend ::DL::Importable
+
+    library_name = case RUBY_PLATFORM.downcase
+      when /darwin/
+        "libsqlite3.dylib"
+      when /linux/
+        "libsqlite3.so"
+      when /win32/
+        "sqlite3.dll"
+      else
+        abort <<-EOF
+== * UNSUPPORTED PLATFORM ======================================================
+The platform '#{RUBY_PLATFORM}' is unsupported. Please help the author by
+editing the following file to allow your sqlite3 library to be found, and
+submitting a patch to jamis_buck@byu.edu. Thanks!
+
+#{__FILE__}
+=========================================================================== * ==
+        EOF
+    end
+
+    if defined? SQLITE3_LIB_PATH
+      library_name = File.join( SQLITE3_LIB_PATH, library_name )
+    end
+
+    dlload library_name
+
+    typealias "db",      "void*"
+    typealias "stmt",    "void*"
+    typealias "value",   "void*"
+    typealias "context", "void*"
+
+    # until Ruby/DL supports 64-bit ints, we'll just treat them as 32-bit ints
+    typealias "int64", "unsigned long"
+
+    extern "const char *sqlite3_libversion()"
+
+    extern "int sqlite3_open(const char*,db*)"
+    extern "int sqlite3_open16(const void*,db*)"
+    extern "int sqlite3_close(db)"
+    extern "const char* sqlite3_errmsg(db)"
+    extern "void* sqlite3_errmsg16(db)"
+    extern "int sqlite3_errcode(db)"
+
+    extern "int sqlite3_prepare(db,const char*,int,stmt*,const char**)"
+    extern "int sqlite3_prepare16(db,const void*,int,stmt*,const void**)"
+    extern "int sqlite3_finalize(stmt)"
+    extern "int sqlite3_reset(stmt)"
+    extern "int sqlite3_step(stmt)"
+
+    extern "int64 sqlite3_last_insert_rowid(db)"
+    extern "int sqlite3_changes(db)"
+    extern "int sqlite3_total_changes(db)"
+    extern "void sqlite3_interrupt(db)"
+    extern "ibool sqlite3_complete(const char*)"
+    extern "ibool sqlite3_complete16(const void*)"
+
+    extern "int sqlite3_busy_handler(db,void*,void*)"
+    extern "int sqlite3_busy_timeout(db,int)"
+
+    extern "int sqlite3_set_authorizer(db,void*,void*)"
+    extern "void* sqlite3_trace(db,void*,void*)"
+
+    extern "int sqlite3_bind_blob(stmt,int,const void*,int,void*)"
+    extern "int sqlite3_bind_double(stmt,int,double)"
+    extern "int sqlite3_bind_int(stmt,int,int)"
+    extern "int sqlite3_bind_int64(stmt,int,int64)"
+    extern "int sqlite3_bind_null(stmt,int)"
+    extern "int sqlite3_bind_text(stmt,int,const char*,int,void*)"
+    extern "int sqlite3_bind_text16(stmt,int,const void*,int,void*)"
+    #extern "int sqlite3_bind_value(stmt,int,value)"
+
+    extern "int sqlite3_bind_parameter_count(stmt)"
+    extern "const char* sqlite3_bind_parameter_name(stmt,int)"
+    extern "int sqlite3_bind_parameter_index(stmt,const char*)"
+
+    extern "int sqlite3_column_count(stmt)"
+    extern "int sqlite3_data_count(stmt)"
+
+    extern "const void *sqlite3_column_blob(stmt,int)"
+    extern "int sqlite3_column_bytes(stmt,int)"
+    extern "int sqlite3_column_bytes16(stmt,int)"
+    extern "const char *sqlite3_column_decltype(stmt,int)"
+    extern "void *sqlite3_column_decltype16(stmt,int)"
+    extern "double sqlite3_column_double(stmt,int)"
+    extern "int sqlite3_column_int(stmt,int)"
+    extern "int64 sqlite3_column_int64(stmt,int)"
+    extern "const char *sqlite3_column_name(stmt,int)"
+    extern "const void *sqlite3_column_name16(stmt,int)"
+    extern "const char *sqlite3_column_text(stmt,int)"
+    extern "const void *sqlite3_column_text16(stmt,int)"
+    extern "int sqlite3_column_type(stmt,int)"
+
+    extern "int sqlite3_create_function(db,const char*,int,int,void*,void*,void*,void*)"
+    extern "int sqlite3_create_function16(db,const void*,int,int,void*,void*,void*,void*)"
+    extern "int sqlite3_aggregate_count(context)"
+
+    extern "const void *sqlite3_value_blob(value)"
+    extern "int sqlite3_value_bytes(value)"
+    extern "int sqlite3_value_bytes16(value)"
+    extern "double sqlite3_value_double(value)"
+    extern "int sqlite3_value_int(value)"
+    extern "int64 sqlite3_value_int64(value)"
+    extern "const char* sqlite3_value_text(value)"
+    extern "const void* sqlite3_value_text16(value)"
+    extern "const void* sqlite3_value_text16le(value)"
+    extern "const void* sqlite3_value_text16be(value)"
+    extern "int sqlite3_value_type(value)"
+
+    extern "void *sqlite3_aggregate_context(context,int)"
+    extern "void *sqlite3_user_data(context)"
+    extern "void *sqlite3_get_auxdata(context,int)"
+    extern "void sqlite3_set_auxdata(context,int,void*,void*)"
+
+    extern "void sqlite3_result_blob(context,const void*,int,void*)"
+    extern "void sqlite3_result_double(context,double)"
+    extern "void sqlite3_result_error(context,const char*,int)"
+    extern "void sqlite3_result_error16(context,const void*,int)"
+    extern "void sqlite3_result_int(context,int)"
+    extern "void sqlite3_result_int64(context,int64)"
+    extern "void sqlite3_result_null(context)"
+    extern "void sqlite3_result_text(context,const char*,int,void*)"
+    extern "void sqlite3_result_text16(context,const void*,int,void*)"
+    extern "void sqlite3_result_text16le(context,const void*,int,void*)"
+    extern "void sqlite3_result_text16be(context,const void*,int,void*)"
+    extern "void sqlite3_result_value(context,value)"
+
+    extern "int sqlite3_create_collation(db,const char*,int,void*,void*)"
+    extern "int sqlite3_create_collation16(db,const char*,int,void*,void*)"
+    extern "int sqlite3_collation_needed(db,void*,void*)"
+    extern "int sqlite3_collation_needed16(db,void*,void*)"
+
+    # ==== CRYPTO (NOT IN PUBLIC RELEASE) ====
+    if defined?( CRYPTO_API ) && CRYPTO_API
+      extern "int sqlite3_key(db,void*,int)"
+      extern "int sqlite3_rekey(db,void*,int)"
+    end
+
+    # ==== EXPERIMENTAL ====
+    if defined?( EXPERIMENTAL_API ) && EXPERIMENTAL_API
+      extern "int sqlite3_progress_handler(db,int,void*,void*)"
+      extern "int sqlite3_commit_hook(db,void*,void*)"
+    end
+
+  end
+
+end ; end ; end
diff --git a/lib/sqlite3/driver/dl/driver.rb b/lib/sqlite3/driver/dl/driver.rb
new file mode 100644
index 0000000..ab24a13
--- /dev/null
+++ b/lib/sqlite3/driver/dl/driver.rb
@@ -0,0 +1,334 @@
+#--
+# =============================================================================
+# Copyright (c) 2004, Jamis Buck (jgb3@email.byu.edu)
+# All rights reserved.
+# 
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are met:
+# 
+#     * Redistributions of source code must retain the above copyright notice,
+#       this list of conditions and the following disclaimer.
+# 
+#     * Redistributions in binary form must reproduce the above copyright
+#       notice, this list of conditions and the following disclaimer in the
+#       documentation and/or other materials provided with the distribution.
+# 
+#     * The names of its contributors may not be used to endorse or promote
+#       products derived from this software without specific prior written
+#       permission.
+# 
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+# DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE
+# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+# SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+# CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+# OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+# =============================================================================
+#++
+
+require 'sqlite3/driver/dl/api'
+
+module Kernel
+  # Allows arbitrary objects to be passed as a pointer to functions.
+  # (Probably not very GC safe, but by encapsulating it like this we
+  # can change the implementation later.)
+  def to_ptr
+    ptr = DL.malloc(DL.sizeof("L"))
+    ptr.set_object self
+    ptr
+  end
+end
+
+class DL::PtrData
+  # The inverse of the Kernel#to_ptr operation.
+  def to_object
+    n = to_s(4).unpack("L").first
+    return nil if n < 1
+    ObjectSpace._id2ref(n) rescue self.to_s
+  end
+
+  def set_object(obj)
+    self[0] = [obj.object_id].pack("L")
+  end
+end
+
+module SQLite3 ; module Driver ; module DL
+
+  class Driver
+    STATIC = ::DL::PtrData.new(0)
+    TRANSIENT = ::DL::PtrData.new(-1)
+
+    def open( filename, utf16=false )
+      handle = ::DL::PtrData.new(0)
+      result = API.send( ( utf16 ? :sqlite3_open16 : :sqlite3_open ),
+        filename+"\0", handle.ref )
+      [ result, handle ]
+    end
+
+    def errmsg( db, utf16=false )
+      if utf16
+        msg = API.sqlite3_errmsg16( db )
+        msg.free = nil
+        msg.to_s(utf16_length(msg))
+      else
+        API.sqlite3_errmsg( db )
+      end
+    end
+
+    def prepare( db, sql, utf16=false )
+      handle = ::DL::PtrData.new(0)
+      remainder = ::DL::PtrData.new(0)
+
+      result = API.send( ( utf16 ? :sqlite3_prepare16 : :sqlite3_prepare ),
+         db, sql+"\0", sql.length, handle.ref, remainder.ref )
+
+      args = utf16 ? [ utf16_length(remainder) ] : []
+      remainder = remainder.to_s( *args )
+
+      [ result, handle, remainder ]
+    end
+
+    def complete?( sql, utf16=false )
+      API.send( utf16 ? :sqlite3_complete16 : :sqlite3_complete, sql+"\0" )
+    end
+
+    def value_blob( value )
+      blob = API.sqlite3_value_blob( value )
+      blob.free = nil
+      blob.to_s( API.sqlite3_value_bytes( value ) )
+    end
+
+    def value_text( value, utf16=false )
+      method = case utf16
+        when nil, false then :sqlite3_value_text
+        when :le then :sqlite3_value_text16le
+        when :be then :sqlite3_value_text16be
+        else :sqlite3_value_text16
+      end
+
+      result = API.send( method, value )
+      if utf16
+        result.free = nil
+        size = API.sqlite3_value_bytes( value )
+        result = result.to_s( size )
+      end
+
+      result
+    end
+
+    def column_blob( stmt, column )
+      blob = API.sqlite3_column_blob( stmt, column )
+      blob.free = nil
+      blob.to_s( API.sqlite3_column_bytes( stmt, column ) )
+    end
+
+    def result_text( func, text, utf16=false )
+      method = case utf16
+        when false, nil then :sqlite3_result_text
+        when :le then :sqlite3_result_text16le
+        when :be then :sqlite3_result_text16be
+        else :sqlite3_result_text16
+      end
+
+      s = text.to_s
+      API.send( method, func, s, s.length, TRANSIENT )
+    end
+
+    def busy_handler( db, data=nil, &block )
+      @busy_handler = block
+
+      unless @busy_handler_callback
+        @busy_handler_callback = ::DL.callback( "IPI" ) do |cookie, timeout|
+          @busy_handler.call( cookie, timeout ) || 0
+        end
+      end
+
+      API.sqlite3_busy_handler( db, block&&@busy_handler_callback, data )
+    end
+
+    def set_authorizer( db, data=nil, &block )
+      @authorizer_handler = block
+
+      unless @authorizer_handler_callback
+        @authorizer_handler_callback = ::DL.callback( "IPIPPPP"
+        ) do |cookie,mode,a,b,c,d|
+          @authorizer_handler.call( cookie, mode,
+            a&&a.to_s, b&&b.to_s, c&&c.to_s, d&&d.to_s ) || 0
+        end
+      end
+
+      API.sqlite3_set_authorizer( db, block&&@authorizer_handler_callback,
+        data )
+    end
+
+    def trace( db, data=nil, &block )
+      @trace_handler = block
+
+      unless @trace_handler_callback
+        @trace_handler_callback = ::DL.callback( "IPS" ) do |cookie,sql|
+          @trace_handler.call( cookie ? cookie.to_object : nil, sql ) || 0
+        end
+      end
+
+      API.sqlite3_trace( db, block&&@trace_handler_callback, data )
+    end
+
+    def create_function( db, name, args, text, cookie,
+      func, step, final )
+    # begin
+      if @func_handler_callback.nil? && func
+        @func_handler_callback = ::DL.callback( "0PIP" ) do |context,nargs,args|
+          args = args.to_s(nargs*4).unpack("L*").map {|i| ::DL::PtrData.new(i)}
+          data = API.sqlite3_user_data( context ).to_object
+          data[:func].call( context, *args )
+        end
+      end
+
+      if @step_handler_callback.nil? && step
+        @step_handler_callback = ::DL.callback( "0PIP" ) do |context,nargs,args|
+          args = args.to_s(nargs*4).unpack("L*").map {|i| ::DL::PtrData.new(i)}
+          data = API.sqlite3_user_data( context ).to_object
+          data[:step].call( context, *args )
+        end
+      end
+
+      if @final_handler_callback.nil? && final
+        @final_handler_callback = ::DL.callback( "0P" ) do |context|
+          data = API.sqlite3_user_data( context ).to_object
+          data[:final].call( context )
+        end
+      end
+
+      data = { :cookie => cookie,
+               :name => name,
+               :func => func,
+               :step => step,
+               :final => final }
+
+      API.sqlite3_create_function( db, name, args, text, data,
+        ( func ? @func_handler_callback : nil ),
+        ( step ? @step_handler_callback : nil ),
+        ( final ? @final_handler_callback : nil ) )
+    end
+
+    def aggregate_context( context )
+      ptr = API.sqlite3_aggregate_context( context, 4 )
+      ptr.free = nil
+      obj = ( ptr ? ptr.to_object : nil )
+      if obj.nil?
+        obj = Hash.new
+        ptr.set_object obj
+      end
+      obj
+    end
+
+    def bind_blob( stmt, index, value )
+      s = value.to_s
+      API.sqlite3_bind_blob( stmt, index, s, s.length, TRANSIENT )
+    end
+
+    def bind_text( stmt, index, value, utf16=false )
+      s = value.to_s
+      method = ( utf16 ? :sqlite3_bind_text16 : :sqlite3_bind_text )
+      API.send( method, stmt, index, s, s.length, TRANSIENT )
+    end
+
+    def column_text( stmt, column )
+      result = API.sqlite3_column_text( stmt, column )
+      result ? result.to_s : nil
+    end
+
+    def column_name( stmt, column )
+      result = API.sqlite3_column_name( stmt, column )
+      result ? result.to_s : nil
+    end
+
+    def column_decltype( stmt, column )
+      result = API.sqlite3_column_decltype( stmt, column )
+      result ? result.to_s : nil
+    end
+
+    def self.api_delegate( name )
+      define_method( name ) { |*args| API.send( "sqlite3_#{name}", *args ) }
+    end
+
+    api_delegate :aggregate_count
+    api_delegate :bind_double
+    api_delegate :bind_int
+    api_delegate :bind_null
+    api_delegate :bind_parameter_index
+    api_delegate :bind_parameter_name
+    api_delegate :busy_timeout
+    api_delegate :changes
+    api_delegate :close
+    api_delegate :column_bytes
+    api_delegate :column_bytes16
+    api_delegate :column_count
+    api_delegate :column_double
+    api_delegate :column_int
+    api_delegate :column_int64
+    api_delegate :column_type
+    api_delegate :data_count
+    api_delegate :errcode
+    api_delegate :finalize
+    api_delegate :interrupt
+    api_delegate :last_insert_rowid
+    api_delegate :libversion
+    api_delegate :reset
+    api_delegate :result_error
+    api_delegate :step
+    api_delegate :total_changes
+    api_delegate :value_bytes
+    api_delegate :value_bytes16
+    api_delegate :value_double
+    api_delegate :value_int
+    api_delegate :value_int64
+    api_delegate :value_type
+
+    # ==== EXPERIMENTAL ====
+    if defined?( EXPERIMENTAL_API ) && EXPERIMENTAL_API
+      def progress_handler( db, n, data=nil, &block )
+        @progress_handler = block
+
+        unless @progress_handler_callback
+          @progress_handler_callback = ::DL.callback( "IP" ) do |cookie|
+            @progress_handler.call( cookie )
+          end
+        end
+
+        API.sqlite3_progress_handler( db, n, block&&@progress_handler_callback,
+          data )
+      end
+
+      def commit_hook( db, data=nil, &block )
+        @commit_hook_handler = block
+
+        unless @commit_hook_handler_callback
+          @commit_hook_handler_callback = ::DL.callback( "IP" ) do |cookie|
+            @commit_hook_handler.call( cookie )
+          end
+        end
+
+        API.sqlite3_commit_hook( db, block&&@commit_hook_handler_callback,
+          data )
+      end
+    end
+
+    private
+
+      def utf16_length(ptr)
+        len = 0
+        loop do
+          break if ptr[len,1] == "\0"
+          len += 2
+        end
+        len
+      end
+
+  end
+
+end ; end ; end
diff --git a/lib/sqlite3/driver/native/driver.rb b/lib/sqlite3/driver/native/driver.rb
new file mode 100644
index 0000000..ee5e4a7
--- /dev/null
+++ b/lib/sqlite3/driver/native/driver.rb
@@ -0,0 +1,218 @@
+#--
+# =============================================================================
+# Copyright (c) 2004, Jamis Buck (jgb3@email.byu.edu)
+# All rights reserved.
+# 
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are met:
+# 
+#     * Redistributions of source code must retain the above copyright notice,
+#       this list of conditions and the following disclaimer.
+# 
+#     * Redistributions in binary form must reproduce the above copyright
+#       notice, this list of conditions and the following disclaimer in the
+#       documentation and/or other materials provided with the distribution.
+# 
+#     * The names of its contributors may not be used to endorse or promote
+#       products derived from this software without specific prior written
+#       permission.
+# 
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+# DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE
+# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+# SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+# CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+# OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+# =============================================================================
+#++
+
+require 'sqlite3_api'
+
+module SQLite3 ; module Driver ; module Native
+
+  class Driver
+
+    def initialize
+      @callback_data = Hash.new
+    end
+
+    def complete?( sql, utf16=false )
+      API.send( utf16 ? :sqlite3_complete16 : :sqlite3_complete, sql ) != 0
+    end
+
+    def busy_handler( db, data=nil, &block )
+      if block
+        cb = API::CallbackData.new
+        cb.proc = block
+        cb.data = data
+      end
+
+      API.sqlite3_busy_handler( db,
+        block ? API::Sqlite3_ruby_busy_handler : nil, cb )
+    end
+
+    def set_authorizer( db, data=nil, &block )
+      if block
+        cb = API::CallbackData.new
+        cb.proc = block
+        cb.data = data
+      end
+
+      API.sqlite3_set_authorizer( db,
+        block ? API::Sqlite3_ruby_authorizer : nil, cb )
+    end
+
+    def trace( db, data=nil, &block )
+      if block
+        cb = API::CallbackData.new
+        cb.proc = block
+        cb.data = data
+      end
+
+      API.sqlite3_trace( db,
+        block ? API::Sqlite3_ruby_trace : nil, cb )
+    end
+
+    def open( filename, utf16=false )
+      API.send( utf16 ? :sqlite3_open16 : :sqlite3_open, filename )
+    end
+
+    def errmsg( db, utf16=false )
+      API.send( utf16 ? :sqlite3_errmsg16 : :sqlite3_errmsg, db )
+    end
+
+    def prepare( db, sql, utf16=false )
+      API.send( ( utf16 ? :sqlite3_prepare16 : :sqlite3_prepare ),
+        db, sql )
+    end
+
+    def bind_text( stmt, index, value, utf16=false )
+      API.send( ( utf16 ? :sqlite3_bind_text16 : :sqlite3_bind_text ),
+        stmt, index, value )
+    end
+
+    def column_name( stmt, index, utf16=false )
+      API.send( ( utf16 ? :sqlite3_column_name16 : :sqlite3_column_name ),
+        stmt, index )
+    end
+
+    def column_decltype( stmt, index, utf16=false )
+      API.send(
+        ( utf16 ? :sqlite3_column_decltype16 : :sqlite3_column_decltype ),
+        stmt, index )
+    end
+
+    def column_text( stmt, index, utf16=false )
+      API.send( ( utf16 ? :sqlite3_column_text16 : :sqlite3_column_text ),
+        stmt, index )
+    end
+
+    def create_function( db, name, args, text, cookie, func, step, final )
+      if func || ( step && final )
+        cb = API::CallbackData.new
+        cb.proc = cb.proc2 = nil
+        cb.data = cookie
+        @callback_data[ name ] = cb
+      else
+        @callback_data.delete( name )
+      end
+
+      if func
+        cb.proc = func
+
+        func = API::Sqlite3_ruby_function_step
+        step = final = nil
+      elsif step && final
+        cb.proc = step
+        cb.proc2 = final
+
+        func = nil
+        step = API::Sqlite3_ruby_function_step
+        final = API::Sqlite3_ruby_function_final
+      end
+
+      API.sqlite3_create_function( db, name, args, text, cb, func, step, final )
+    end
+
+    def value_text( value, utf16=false )
+      method = case utf16
+        when nil, false then :sqlite3_value_text
+        when :le then :sqlite3_value_text16le
+        when :be then :sqlite3_value_text16be
+        else :sqlite3_value_text16
+      end
+
+      API.send( method, value )
+    end
+
+    def result_text( context, result, utf16=false )
+      method = case utf16
+        when nil, false then :sqlite3_result_text
+        when :le then :sqlite3_result_text16le
+        when :be then :sqlite3_result_text16be
+        else :sqlite3_result_text16
+      end
+
+      API.send( method, context, result.to_s )
+    end
+
+    def result_error( context, value, utf16=false )
+      API.send( ( utf16 ? :sqlite3_result_error16 : :sqlite3_result_error ),
+        context, value )
+    end
+
+    def self.api_delegate( name )
+      define_method( name ) { |*args| API.send( "sqlite3_#{name}", *args ) }
+    end
+
+    api_delegate :libversion
+    api_delegate :close
+    api_delegate :last_insert_rowid
+    api_delegate :changes
+    api_delegate :total_changes
+    api_delegate :interrupt
+    api_delegate :busy_timeout
+    api_delegate :errcode
+    api_delegate :bind_blob
+    api_delegate :bind_double
+    api_delegate :bind_int
+    api_delegate :bind_int64
+    api_delegate :bind_null
+    api_delegate :bind_parameter_count
+    api_delegate :bind_parameter_name
+    api_delegate :bind_parameter_index
+    api_delegate :column_count
+    api_delegate :step
+    api_delegate :data_count
+    api_delegate :column_blob
+    api_delegate :column_bytes
+    api_delegate :column_bytes16
+    api_delegate :column_double
+    api_delegate :column_int
+    api_delegate :column_int64
+    api_delegate :column_type
+    api_delegate :finalize
+    api_delegate :reset
+    api_delegate :aggregate_count
+    api_delegate :value_blob
+    api_delegate :value_bytes
+    api_delegate :value_bytes16
+    api_delegate :value_double
+    api_delegate :value_int
+    api_delegate :value_int64
+    api_delegate :value_type
+    api_delegate :result_blob
+    api_delegate :result_double
+    api_delegate :result_int
+    api_delegate :result_int64
+    api_delegate :result_null
+    api_delegate :result_value
+    api_delegate :aggregate_context
+
+  end
+
+end ; end ; end
diff --git a/lib/sqlite3/errors.rb b/lib/sqlite3/errors.rb
new file mode 100644
index 0000000..308a4c9
--- /dev/null
+++ b/lib/sqlite3/errors.rb
@@ -0,0 +1,84 @@
+#--
+# =============================================================================
+# Copyright (c) 2004, Jamis Buck (jgb3@email.byu.edu)
+# All rights reserved.
+# 
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are met:
+# 
+#     * Redistributions of source code must retain the above copyright notice,
+#       this list of conditions and the following disclaimer.
+# 
+#     * Redistributions in binary form must reproduce the above copyright
+#       notice, this list of conditions and the following disclaimer in the
+#       documentation and/or other materials provided with the distribution.
+# 
+#     * The names of its contributors may not be used to endorse or promote
+#       products derived from this software without specific prior written
+#       permission.
+# 
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+# DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE
+# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+# SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+# CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+# OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+# =============================================================================
+#++
+
+require 'sqlite3/constants'
+
+module SQLite3
+
+  class Exception < ::Exception; end
+
+  class SQLException < Exception; end
+  class InternalException < Exception; end
+  class PermissionException < Exception; end
+  class AbortException < Exception; end
+  class BusyException < Exception; end
+  class LockedException < Exception; end
+  class MemoryException < Exception; end
+  class ReadOnlyException < Exception; end
+  class InterruptException < Exception; end
+  class IOException < Exception; end
+  class CorruptException < Exception; end
+  class NotFoundException < Exception; end
+  class FullException < Exception; end
+  class CantOpenException < Exception; end
+  class ProtocolException < Exception; end
+  class EmptyException < Exception; end
+  class SchemaChangedException < Exception; end
+  class TooBigException < Exception; end
+  class ConstraintException < Exception; end
+  class MismatchException < Exception; end
+  class MisuseException < Exception; end
+  class UnsupportedException < Exception; end
+  class AuthorizationException < Exception; end
+
+  EXCEPTIONS = [
+    nil,
+    SQLException, InternalException, PermissionException,
+    AbortException, BusyException, LockedException, MemoryException,
+    ReadOnlyException, InterruptException, IOException, CorruptException,
+    NotFoundException, FullException, CantOpenException, ProtocolException,
+    EmptyException, SchemaChangedException, TooBigException,
+    ConstraintException, MismatchException, MisuseException,
+    UnsupportedException, AuthorizationException
+  ]
+
+  module Error
+    def check( result, db=nil, msg=nil )
+      unless result == Constants::ErrorCode::OK
+        msg = ( msg ? msg + ": " : "" ) + db.errmsg if db
+        raise EXCEPTIONS[result], msg
+      end
+    end
+    module_function :check
+  end
+
+end
diff --git a/lib/sqlite3/pragmas.rb b/lib/sqlite3/pragmas.rb
new file mode 100644
index 0000000..7247387
--- /dev/null
+++ b/lib/sqlite3/pragmas.rb
@@ -0,0 +1,254 @@
+#--
+# =============================================================================
+# Copyright (c) 2004, Jamis Buck (jgb3@email.byu.edu)
+# All rights reserved.
+# 
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are met:
+# 
+#     * Redistributions of source code must retain the above copyright notice,
+#       this list of conditions and the following disclaimer.
+# 
+#     * Redistributions in binary form must reproduce the above copyright
+#       notice, this list of conditions and the following disclaimer in the
+#       documentation and/or other materials provided with the distribution.
+# 
+#     * The names of its contributors may not be used to endorse or promote
+#       products derived from this software without specific prior written
+#       permission.
+# 
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+# DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE
+# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+# SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+# CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+# OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+# =============================================================================
+#++
+
+require 'sqlite3/errors'
+
+module SQLite3
+
+  # This module is intended for inclusion solely by the Database class. It
+  # defines convenience methods for the various pragmas supported by SQLite3.
+  #
+  # For a detailed description of these pragmas, see the SQLite3 documentation
+  # at http://sqlite.org/pragma.html.
+  module Pragmas
+
+    # Returns +true+ or +false+ depending on the value of the named pragma.
+    def get_boolean_pragma( name )
+      get_first_value( "PRAGMA #{name}" ) != "0"
+    end
+    private :get_boolean_pragma
+
+    # Sets the given pragma to the given boolean value. The value itself
+    # may be +true+ or +false+, or any other commonly used string or
+    # integer that represents truth.
+    def set_boolean_pragma( name, mode )
+      case mode
+        when String
+          case mode.downcase
+            when "on", "yes", "true", "y", "t": mode = "'ON'"
+            when "off", "no", "false", "n", "f": mode = "'OFF'"
+            else
+              raise Exception,
+                "unrecognized pragma parameter #{mode.inspect}"
+          end
+        when true, 1
+          mode = "ON"
+        when false, 0, nil
+          mode = "OFF"
+        else
+          raise Exception,
+            "unrecognized pragma parameter #{mode.inspect}"
+      end
+
+      execute( "PRAGMA #{name}=#{mode}" )
+    end
+    private :set_boolean_pragma
+
+    # Requests the given pragma (and parameters), and if the block is given,
+    # each row of the result set will be yielded to it. Otherwise, the results
+    # are returned as an array.
+    def get_query_pragma( name, *parms, &block ) # :yields: row
+      if parms.empty?
+        execute( "PRAGMA #{name}", &block )
+      else
+        args = "'" + parms.join("','") + "'"
+        execute( "PRAGMA #{name}( #{args} )", &block )
+      end
+    end
+    private :get_query_pragma
+
+    # Return the value of the given pragma.
+    def get_enum_pragma( name )
+      get_first_value( "PRAGMA #{name}" )
+    end
+    private :get_enum_pragma
+
+    # Set the value of the given pragma to +mode+. The +mode+ parameter must
+    # conform to one of the values in the given +enum+ array. Each entry in
+    # the array is another array comprised of elements in the enumeration that
+    # have duplicate values. See #synchronous, #default_synchronous,
+    # #temp_store, and #default_temp_store for usage examples.
+    def set_enum_pragma( name, mode, enums )
+      match = enums.find { |p| p.find { |i| i.to_s.downcase == mode.to_s.downcase } }
+      raise Exception,
+        "unrecognized #{name} #{mode.inspect}" unless match
+      execute( "PRAGMA #{name}='#{match.first.upcase}'" )
+    end
+    private :set_enum_pragma
+
+    # Returns the value of the given pragma as an integer.
+    def get_int_pragma( name )
+      get_first_value( "PRAGMA #{name}" ).to_i
+    end
+    private :get_int_pragma
+
+    # Set the value of the given pragma to the integer value of the +value+
+    # parameter.
+    def set_int_pragma( name, value )
+      execute( "PRAGMA #{name}=#{value.to_i}" )
+    end
+    private :set_int_pragma
+
+    # The enumeration of valid synchronous modes.
+    SYNCHRONOUS_MODES = [ [ 'full', 2 ], [ 'normal', 1 ], [ 'off', 0 ] ]
+
+    # The enumeration of valid temp store modes.
+    TEMP_STORE_MODES  = [ [ 'default', 0 ], [ 'file', 1 ], [ 'memory', 2 ] ]
+
+    # Does an integrity check on the database. If the check fails, a
+    # SQLite3::Exception will be raised. Otherwise it
+    # returns silently.
+    def integrity_check
+      execute( "PRAGMA integrity_check" ) do |row|
+        raise Exception, row[0] if row[0] != "ok"
+      end
+    end
+
+    def auto_vacuum
+      get_boolean_pragma "auto_vacuum"
+    end
+
+    def auto_vacuum=( mode )
+      set_boolean_pragma "auto_vacuum", mode
+    end
+
+    def schema_cookie
+      get_int_pragma "schema_cookie"
+    end
+
+    def schema_cookie=( cookie )
+      set_int_pragma "schema_cookie", cookie
+    end
+
+    def user_cookie
+      get_int_pragma "user_cookie"
+    end
+
+    def user_cookie=( cookie )
+      set_int_pragma "user_cookie", cookie
+    end
+
+    def cache_size
+      get_int_pragma "cache_size"
+    end
+
+    def cache_size=( size )
+      set_int_pragma "cache_size", size
+    end
+
+    def default_cache_size
+      get_int_pragma "default_cache_size"
+    end
+
+    def default_cache_size=( size )
+      set_int_pragma "default_cache_size", size
+    end
+
+    def default_synchronous
+      get_enum_pragma "default_synchronous"
+    end
+
+    def default_synchronous=( mode )
+      set_enum_pragma "default_synchronous", mode, SYNCHRONOUS_MODES
+    end
+
+    def synchronous
+      get_enum_pragma "synchronous"
+    end
+
+    def synchronous=( mode )
+      set_enum_pragma "synchronous", mode, SYNCHRONOUS_MODES
+    end
+
+    def default_temp_store
+      get_enum_pragma "default_temp_store"
+    end
+
+    def default_temp_store=( mode )
+      set_enum_pragma "default_temp_store", mode, TEMP_STORE_MODES
+    end
+  
+    def temp_store
+      get_enum_pragma "temp_store"
+    end
+
+    def temp_store=( mode )
+      set_enum_pragma "temp_store", mode, TEMP_STORE_MODES
+    end
+
+    def full_column_names
+      get_boolean_pragma "full_column_names"
+    end
+
+    def full_column_names=( mode )
+      set_boolean_pragma "full_column_names", mode
+    end
+  
+    def parser_trace
+      get_boolean_pragma "parser_trace"
+    end
+
+    def parser_trace=( mode )
+      set_boolean_pragma "parser_trace", mode
+    end
+  
+    def vdbe_trace
+      get_boolean_pragma "vdbe_trace"
+    end
+
+    def vdbe_trace=( mode )
+      set_boolean_pragma "vdbe_trace", mode
+    end
+
+    def database_list( &block ) # :yields: row
+      get_query_pragma "database_list", &block
+    end
+
+    def foreign_key_list( table, &block ) # :yields: row
+      get_query_pragma "foreign_key_list", table, &block
+    end
+
+    def index_info( index, &block ) # :yields: row
+      get_query_pragma "index_info", index, &block
+    end
+
+    def index_list( table, &block ) # :yields: row
+      get_query_pragma "index_list", table, &block
+    end
+
+    def table_info( table, &block ) # :yields: row
+      get_query_pragma "table_info", table, &block
+    end
+  
+  end
+
+end
diff --git a/lib/sqlite3/resultset.rb b/lib/sqlite3/resultset.rb
new file mode 100644
index 0000000..bef2a0d
--- /dev/null
+++ b/lib/sqlite3/resultset.rb
@@ -0,0 +1,172 @@
+#--
+# =============================================================================
+# Copyright (c) 2004, Jamis Buck (jgb3@email.byu.edu)
+# All rights reserved.
+# 
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are met:
+# 
+#     * Redistributions of source code must retain the above copyright notice,
+#       this list of conditions and the following disclaimer.
+# 
+#     * Redistributions in binary form must reproduce the above copyright
+#       notice, this list of conditions and the following disclaimer in the
+#       documentation and/or other materials provided with the distribution.
+# 
+#     * The names of its contributors may not be used to endorse or promote
+#       products derived from this software without specific prior written
+#       permission.
+# 
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+# DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE
+# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+# SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+# CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+# OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+# =============================================================================
+#++
+
+require 'sqlite3/constants'
+require 'sqlite3/errors'
+
+module SQLite3
+
+  # The ResultSet object encapsulates the enumerability of a query's output.
+  # It is a simple cursor over the data that the query returns. It will
+  # very rarely (if ever) be instantiated directly. Instead, client's should
+  # obtain a ResultSet instance via Statement#execute.
+  class ResultSet
+    include Enumerable
+
+    # A trivial module for adding a +types+ accessor to an object.
+    module TypesContainer
+      attr_accessor :types
+    end
+
+    # A trivial module for adding a +fields+ accessor to an object.
+    module FieldsContainer
+      attr_accessor :fields
+    end
+
+    # Create a new ResultSet attached to the given database, using the
+    # given sql text.
+    def initialize( db, stmt )
+      @db = db
+      @driver = @db.driver
+      @stmt = stmt
+      commence
+    end
+
+    # A convenience method for compiling the virtual machine and stepping
+    # to the first row of the result set.
+    def commence
+      result = @driver.step( @stmt.handle )
+      check result
+      @first_row = true
+    end
+    private :commence
+
+    def check( result )
+      @eof = ( result == Constants::ErrorCode::DONE )
+      found = ( result == Constants::ErrorCode::ROW )
+      Error.check( result, @db ) unless @eof || found
+    end
+    private :check
+
+    # Reset the cursor, so that a result set which has reached end-of-file
+    # can be rewound and reiterated.
+    def reset( *bind_params )
+      @driver.reset( @stmt.handle )
+      @stmt.bind_params( *bind_params )
+      @eof = false
+      commence
+    end
+
+    # Query whether the cursor has reached the end of the result set or not.
+    def eof?
+      @eof
+    end
+
+    # Obtain the next row from the cursor. If there are no more rows to be
+    # had, this will return +nil+. If type translation is active on the
+    # corresponding database, the values in the row will be translated
+    # according to their types.
+    #
+    # The returned value will be an array, unless Database#results_as_hash has
+    # been set to +true+, in which case the returned value will be a hash.
+    #
+    # For arrays, the column names are accessible via the +fields+ property,
+    # and the column types are accessible via the +types+ property.
+    #
+    # For hashes, the column names are the keys of the hash, and the column
+    # types are accessible via the +types+ property.
+    def next
+      return nil if @eof
+
+      unless @first_row
+        result = @driver.step( @stmt.handle )
+        check result
+      end
+
+      @first_row = false
+
+      unless @eof
+        row = []
+        @driver.data_count( @stmt.handle ).times do |column|
+          case @driver.column_type( @stmt.handle, column )
+            when Constants::ColumnType::NULL then
+              row << nil
+            when Constants::ColumnType::BLOB then
+              row << @driver.column_blob( @stmt.handle, column )
+            else
+              row << @driver.column_text( @stmt.handle, column )
+          end
+        end
+
+        if @db.type_translation
+          row = @stmt.types.zip( row ).map do |type, value|
+            @db.translator.translate( type, value )
+          end
+        end
+
+        if @db.results_as_hash
+          new_row = Hash[ *( @stmt.columns.zip( row ).flatten ) ]
+          row.each_with_index { |value,idx| new_row[idx] = value }
+          row = new_row
+        else
+          row.extend FieldsContainer unless row.respond_to?(:fields)
+          row.fields = @stmt.columns
+        end
+
+        row.extend TypesContainer
+        row.types = @stmt.types
+
+        return row
+      end
+
+      nil
+    end
+
+    # Required by the Enumerable mixin. Provides an internal iterator over the
+    # rows of the result set.
+    def each
+      while row=self.next
+        yield row
+      end
+    end
+
+    def types
+      @stmt.types
+    end
+
+    def columns
+      @stmt.columns
+    end
+
+  end
+
+end
diff --git a/lib/sqlite3/statement.rb b/lib/sqlite3/statement.rb
new file mode 100644
index 0000000..8d2e3d5
--- /dev/null
+++ b/lib/sqlite3/statement.rb
@@ -0,0 +1,218 @@
+#--
+# =============================================================================
+# Copyright (c) 2004, Jamis Buck (jgb3@email.byu.edu)
+# All rights reserved.
+# 
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are met:
+# 
+#     * Redistributions of source code must retain the above copyright notice,
+#       this list of conditions and the following disclaimer.
+# 
+#     * Redistributions in binary form must reproduce the above copyright
+#       notice, this list of conditions and the following disclaimer in the
+#       documentation and/or other materials provided with the distribution.
+# 
+#     * The names of its contributors may not be used to endorse or promote
+#       products derived from this software without specific prior written
+#       permission.
+# 
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+# DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE
+# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+# SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+# CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+# OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+# =============================================================================
+#++
+
+require 'sqlite3/errors'
+require 'sqlite3/resultset'
+
+class String
+  def to_blob
+    SQLite3::Blob.new( self )
+  end
+end
+
+module SQLite3
+
+  # A class for differentiating between strings and blobs, when binding them
+  # into statements.
+  class Blob < String; end
+
+  # A statement represents a prepared-but-unexecuted SQL query. It will rarely
+  # (if ever) be instantiated directly by a client, and is most often obtained
+  # via the Database#prepare method.
+  class Statement
+
+    # This is any text that followed the first valid SQL statement in the text
+    # with which the statement was initialized. If there was no trailing text,
+    # this will be the empty string.
+    attr_reader :remainder
+
+    # The underlying opaque handle used to access the SQLite @driver.
+    attr_reader :handle
+
+    # Create a new statement attached to the given Database instance, and which
+    # encapsulates the given SQL text. If the text contains more than one
+    # statement (i.e., separated by semicolons), then the #remainder property
+    # will be set to the trailing text.
+    def initialize( db, sql, utf16=false )
+      @db = db
+      @driver = @db.driver
+      result, @handle, @remainder = @driver.prepare( @db.handle, sql )
+      Error.check( result, @db )
+    end
+
+    def close
+      @driver.finalize( @handle )
+    end
+
+    # Binds the given variables to the corresponding placeholders in the SQL
+    # text.
+    #
+    # See Database#execute for a description of the valid placeholder
+    # syntaxes.
+    #
+    # Example:
+    #
+    #   stmt = db.prepare( "select * from table where a=? and b=?" )
+    #   stmt.bind_params( 15, "hello" )
+    #
+    # See also #execute, #bind_param, Statement#bind_param, and
+    # Statement#bind_params.
+    def bind_params( *bind_vars )
+      index = 1
+      bind_vars.each do |var|
+        if Hash === var
+          var.each { |key, val| bind_param key, val }
+        else
+          bind_param index, var
+          index += 1
+        end
+      end
+    end
+
+    # Binds value to the named (or positional) placeholder. If +param+ is a
+    # Fixnum, it is treated as an index for a positional placeholder.
+    # Otherwise it is used as the name of the placeholder to bind to.
+    #
+    # See also #bind_params.
+    def bind_param( param, value )
+      if Fixnum === param
+        case value
+          when Integer then
+            @driver.bind_int( @handle, param, value )
+          when Numeric then
+            @driver.bind_double( @handle, param, value.to_f )
+          when Blob then
+            @driver.bind_blob( @handle, param, value )
+          when nil then
+            @driver.bind_null( @handle, param )
+          else
+            @driver.bind_text( @handle, param, value )
+        end
+      else
+        index = @driver.bind_parameter_index(
+          @handle, param.to_s )
+        raise Exception, "no such bind parameter '#{param}'" if index == 0
+        bind_param index, value
+      end
+    end
+
+    # Execute the statement. This creates a new ResultSet object for the
+    # statement's virtual machine. If a block was given, the new ResultSet will
+    # be yielded to it; otherwise, the ResultSet will be returned.
+    #
+    # Any parameters will be bound to the statement using #bind_params.
+    #
+    # Example:
+    #
+    #   stmt = db.prepare( "select * from table" )
+    #   stmt.execute do |result|
+    #     ...
+    #   end
+    #
+    # See also #bind_params, #execute!.
+    def execute( *bind_vars )
+      @driver.reset( @handle ) if @results
+
+      bind_params *bind_vars unless bind_vars.empty?
+      @results = ResultSet.new( @db, self )
+
+      if block_given?
+        yield @results
+      else
+        return @results
+      end
+    end
+
+    # Execute the statement. If no block was given, this returns an array of
+    # rows returned by executing the statement. Otherwise, each row will be
+    # yielded to the block.
+    #
+    # Any parameters will be bound to the statement using #bind_params.
+    #
+    # Example:
+    #
+    #   stmt = db.prepare( "select * from table" )
+    #   stmt.execute! do |row|
+    #     ...
+    #   end
+    #
+    # See also #bind_params, #execute.
+    def execute!( *bind_vars )
+      result = execute( *bind_vars )
+      rows = [] unless block_given?
+      while row = result.next
+        if block_given?
+          yield row
+        else
+          rows << row
+        end
+      end
+      rows
+    end
+
+    # Return an array of the column names for this statement. Note that this
+    # may execute the statement in order to obtain the metadata; this makes it
+    # a (potentially) expensive operation.
+    def columns
+      get_metadata unless @columns
+      return @columns
+    end
+
+    # Return an array of the data types for each column in this statement. Note
+    # that this may execute the statement in order to obtain the metadata; this
+    # makes it a (potentially) expensive operation.
+    def types
+      get_metadata unless @types
+      return @types
+    end
+
+    # A convenience method for obtaining the metadata about the query. Note
+    # that this will actually execute the SQL, which means it can be a
+    # (potentially) expensive operation.
+    def get_metadata
+      @columns = []
+      @types = []
+
+      column_count = @driver.column_count( @handle )
+      column_count.times do |column|
+        @columns << @driver.column_name( @handle, column )
+        @types << @driver.column_decltype( @handle, column )
+      end
+
+      @columns.freeze
+      @types.freeze
+    end
+    private :get_metadata
+
+  end
+
+end
diff --git a/lib/sqlite3/translator.rb b/lib/sqlite3/translator.rb
new file mode 100644
index 0000000..1ee315e
--- /dev/null
+++ b/lib/sqlite3/translator.rb
@@ -0,0 +1,135 @@
+#--
+# =============================================================================
+# Copyright (c) 2004, Jamis Buck (jgb3@email.byu.edu)
+# All rights reserved.
+# 
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are met:
+# 
+#     * Redistributions of source code must retain the above copyright notice,
+#       this list of conditions and the following disclaimer.
+# 
+#     * Redistributions in binary form must reproduce the above copyright
+#       notice, this list of conditions and the following disclaimer in the
+#       documentation and/or other materials provided with the distribution.
+# 
+#     * The names of its contributors may not be used to endorse or promote
+#       products derived from this software without specific prior written
+#       permission.
+# 
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+# DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE
+# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+# SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+# CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+# OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+# =============================================================================
+#++
+
+require 'time'
+
+module SQLite3
+
+  # The Translator class encapsulates the logic and callbacks necessary for
+  # converting string data to a value of some specified type. Every Database
+  # instance may have a Translator instance, in order to assist in type
+  # translation (Database#type_translation).
+  #
+  # Further, applications may define their own custom type translation logic
+  # by registering translator blocks with the corresponding database's
+  # translator instance (Database#translator).
+  class Translator
+
+    # Create a new Translator instance. It will be preinitialized with default
+    # translators for most SQL data types.
+    def initialize
+      @translators = Hash.new( proc { |type,value| value } )
+      register_default_translators
+    end
+
+    # Add a new translator block, which will be invoked to process type
+    # translations to the given type. The type should be an SQL datatype, and
+    # may include parentheses (i.e., "VARCHAR(30)"). However, any parenthetical
+    # information is stripped off and discarded, so type translation decisions
+    # are made solely on the "base" type name.
+    #
+    # The translator block itself should accept two parameters, "type" and
+    # "value". In this case, the "type" is the full type name (including
+    # parentheses), so the block itself may include logic for changing how a
+    # type is translated based on the additional data. The "value" parameter
+    # is the (string) data to convert.
+    #
+    # The block should return the translated value.
+    def add_translator( type, &block ) # :yields: type, value
+      @translators[ type_name( type ) ] = block
+    end
+
+    # Translate the given string value to a value of the given type. In the
+    # absense of an installed translator block for the given type, the value
+    # itself is always returned. Further, +nil+ values are never translated,
+    # and are always passed straight through regardless of the type parameter.
+    def translate( type, value )
+      unless value.nil?
+        @translators[ type_name( type ) ].call( type, value )
+      end
+    end
+
+    # A convenience method for working with type names. This returns the "base"
+    # type name, without any parenthetical data.
+    def type_name( type )
+      type = $1 if type =~ /^(.*?)\(/
+      type.upcase
+    end
+    private :type_name
+
+    # Register the default translators for the current Translator instance.
+    # This includes translators for most major SQL data types.
+    def register_default_translators
+      [ "date",
+        "datetime",
+        "time" ].each { |type| add_translator( type ) { |t,v| Time.parse( v ) } }
+
+      [ "decimal",
+        "float",
+        "numeric",
+        "double",
+        "real",
+        "dec",
+        "fixed" ].each { |type| add_translator( type ) { |t,v| v.to_f } }
+
+      [ "integer",
+        "smallint",
+        "mediumint",
+        "int",
+        "bigint" ].each { |type| add_translator( type ) { |t,v| v.to_i } }
+
+      [ "bit",
+        "bool",
+        "boolean" ].each do |type|
+        add_translator( type ) do |t,v|
+          !( v.strip.gsub(/00+/,"0") == "0" ||
+             v.downcase == "false" ||
+             v.downcase == "f" ||
+             v.downcase == "no" ||
+             v.downcase == "n" )
+        end
+      end
+
+      add_translator( "timestamp" ) { |type, value| Time.at( value.to_i ) }
+      add_translator( "tinyint" ) do |type, value|
+        if type =~ /\(\s*1\s*\)/
+          value.to_i == 1
+        else
+          value.to_i
+        end
+      end
+    end
+    private :register_default_translators
+
+  end
+
+end
diff --git a/lib/sqlite3/value.rb b/lib/sqlite3/value.rb
new file mode 100644
index 0000000..fb76376
--- /dev/null
+++ b/lib/sqlite3/value.rb
@@ -0,0 +1,89 @@
+#--
+# =============================================================================
+# Copyright (c) 2004, Jamis Buck (jgb3@email.byu.edu)
+# All rights reserved.
+# 
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are met:
+# 
+#     * Redistributions of source code must retain the above copyright notice,
+#       this list of conditions and the following disclaimer.
+# 
+#     * Redistributions in binary form must reproduce the above copyright
+#       notice, this list of conditions and the following disclaimer in the
+#       documentation and/or other materials provided with the distribution.
+# 
+#     * The names of its contributors may not be used to endorse or promote
+#       products derived from this software without specific prior written
+#       permission.
+# 
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+# DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE
+# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+# SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+# CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+# OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+# =============================================================================
+#++
+
+require 'sqlite3/constants'
+
+module SQLite3
+
+  class Value
+    attr_reader :handle
+
+    def initialize( db, handle )
+      @driver = db.driver
+      @handle = handle
+    end
+
+    def null?
+      type == :null
+    end
+
+    def to_blob
+      @driver.value_blob( @handle )
+    end
+
+    def length( utf16=false )
+      if utf16
+        @driver.value_bytes16( @handle )
+      else
+        @driver.value_bytes( @handle )
+      end
+    end
+
+    def to_f
+      @driver.value_double( @handle )
+    end
+
+    def to_i
+      @driver.value_int( @handle )
+    end
+
+    def to_int64
+      @driver.value_int64( @handle )
+    end
+
+    def to_s( utf16=false )
+      @driver.value_text( @handle, utf16 )
+    end
+
+    def type
+      case @driver.value_type( @handle )
+        when Constants::ColumnType::INTEGER then :int
+        when Constants::ColumnType::FLOAT   then :float
+        when Constants::ColumnType::TEXT    then :text
+        when Constants::ColumnType::BLOB    then :blob
+        when Constants::ColumnType::NULL    then :null
+      end
+    end
+    
+  end
+
+end
diff --git a/lib/sqlite3/version.rb b/lib/sqlite3/version.rb
new file mode 100644
index 0000000..542cd75
--- /dev/null
+++ b/lib/sqlite3/version.rb
@@ -0,0 +1,45 @@
+#--
+# =============================================================================
+# Copyright (c) 2004, Jamis Buck (jgb3@email.byu.edu)
+# All rights reserved.
+# 
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are met:
+# 
+#     * Redistributions of source code must retain the above copyright notice,
+#       this list of conditions and the following disclaimer.
+# 
+#     * Redistributions in binary form must reproduce the above copyright
+#       notice, this list of conditions and the following disclaimer in the
+#       documentation and/or other materials provided with the distribution.
+# 
+#     * The names of its contributors may not be used to endorse or promote
+#       products derived from this software without specific prior written
+#       permission.
+# 
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+# DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE
+# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+# SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+# CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+# OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+# =============================================================================
+#++
+
+module SQLite3
+
+  module Version
+
+    MAJOR = 0
+    MINOR = 9
+    TINY  = 0
+
+    STRING = [ MAJOR, MINOR, TINY ].join( "." )
+
+  end
+
+end