SoundSoftware Code Site

module CodeRay module Scanners

  # by Josh Goebel

  class SQL < Scanner

    register_for :sql

    RESERVED_WORDS = %w(

      create database table index trigger drop primary key set select

      insert update delete replace into

      on from values before and or if exists case when

      then else as group order by avg where

      join inner outer union engine not

      like end using collate show columns begin

    )

    PREDEFINED_TYPES = %w(

      char varchar enum binary text tinytext mediumtext

      longtext blob tinyblob mediumblob longblob timestamp

      date time datetime year double decimal float int

      integer tinyint mediumint bigint smallint unsigned bit

      bool boolean hex bin oct

    )

    PREDEFINED_FUNCTIONS = %w( sum cast abs pi count min max avg )

    DIRECTIVES = %w( auto_increment unique default charset )

    PREDEFINED_CONSTANTS = %w( null true false )

    IDENT_KIND = CaseIgnoringWordList.new(:ident).

      add(RESERVED_WORDS, :reserved).

      add(PREDEFINED_TYPES, :pre_type).

      add(PREDEFINED_CONSTANTS, :pre_constant).

      add(PREDEFINED_FUNCTIONS, :predefined).

      add(DIRECTIVES, :directive)

    ESCAPE = / [rbfntv\n\\\/'"] | x[a-fA-F0-9]{1,2} | [0-7]{1,3} | . /mx

    UNICODE_ESCAPE =  / u[a-fA-F0-9]{4} | U[a-fA-F0-9]{8} /x

    STRING_PREFIXES = /[xnb]|_\w+/i

    def scan_tokens tokens, options

      state = :initial

      string_type = nil

      string_content = ''

      until eos?

        kind = nil

        match = nil

        if state == :initial

          if scan(/ \s+ | \\\n /x)

            kind = :space

          elsif scan(/(?:--\s?|#).*/)

            kind = :comment

          elsif scan(%r! /\* (?: .*? \*/ | .* ) !mx)

            kind = :comment

          elsif scan(/ [-+*\/=<>;,!&^|()\[\]{}~%] | \.(?!\d) /x)

            kind = :operator

          elsif scan(/(#{STRING_PREFIXES})?([`"'])/o)

            prefix = self[1]

            string_type = self[2]

            tokens << [:open, :string]

            tokens << [prefix, :modifier] if prefix

            match = string_type

            state = :string

            kind = :delimiter

          elsif match = scan(/ @? [A-Za-z_][A-Za-z_0-9]* /x)

            kind = match[0] == ?@ ? :variable : IDENT_KIND[match.downcase]

          elsif scan(/0[xX][0-9A-Fa-f]+/)

            kind = :hex

          elsif scan(/0[0-7]+(?![89.eEfF])/)

            kind = :oct

          elsif scan(/(?>\d+)(?![.eEfF])/)

            kind = :integer

          elsif scan(/\d[fF]|\d*\.\d+(?:[eE][+-]?\d+)?|\d+[eE][+-]?\d+/)

            kind = :float

          else

            getch

            kind = :error

          end

        elsif state == :string

          if match = scan(/[^\\"'`]+/)

            string_content << match

            next

          elsif match = scan(/["'`]/)

            if string_type == match

              if peek(1) == string_type  # doubling means escape

                string_content << string_type << getch

                next

              end

              unless string_content.empty?

                tokens << [string_content, :content]

                string_content = ''

              end

              tokens << [matched, :delimiter]

              tokens << [:close, :string]

              state = :initial

              string_type = nil

              next

            else

              string_content << match

            end

            next

          elsif scan(/ \\ (?: #{ESCAPE} | #{UNICODE_ESCAPE} ) /mox)

            unless string_content.empty?

              tokens << [string_content, :content]

              string_content = ''

            end

            kind = :char

          elsif match = scan(/ \\ . /mox)

            string_content << match

            next

          elsif scan(/ \\ | $ /x)

            unless string_content.empty?

              tokens << [string_content, :content]

              string_content = ''

            end

            kind = :error

            state = :initial

          else

            raise "else case \" reached; %p not handled." % peek(1), tokens

          end

        else

          raise 'else-case reached', tokens

        end

        match ||= matched

        unless kind

          raise_inspect 'Error token %p in line %d' %

            [[match, kind], line], tokens, state

        end

        raise_inspect 'Empty token', tokens unless match

        tokens << [match, kind]

      end

      tokens

    end

  end

end end