JezK
Edit File: core.rb
# frozen_string_literal: true #-- # Methods for generating HTML, parsing CGI-related parameters, and # generating HTTP responses. #++ class CGI unless const_defined?(:Util) module Util @@accept_charset = "UTF-8" # :nodoc: end include Util extend Util end $CGI_ENV = ENV # for FCGI support # String for carriage return CR = "\015" # String for linefeed LF = "\012" # Standard internet newline sequence EOL = CR + LF REVISION = '$Id$' #:nodoc: # Whether processing will be required in binary vs text NEEDS_BINMODE = File::BINARY != 0 # Path separators in different environments. PATH_SEPARATOR = {'UNIX'=>'/', 'WINDOWS'=>'\\', 'MACINTOSH'=>':'} # HTTP status codes. HTTP_STATUS = { "OK" => "200 OK", "PARTIAL_CONTENT" => "206 Partial Content", "MULTIPLE_CHOICES" => "300 Multiple Choices", "MOVED" => "301 Moved Permanently", "REDIRECT" => "302 Found", "NOT_MODIFIED" => "304 Not Modified", "BAD_REQUEST" => "400 Bad Request", "AUTH_REQUIRED" => "401 Authorization Required", "FORBIDDEN" => "403 Forbidden", "NOT_FOUND" => "404 Not Found", "METHOD_NOT_ALLOWED" => "405 Method Not Allowed", "NOT_ACCEPTABLE" => "406 Not Acceptable", "LENGTH_REQUIRED" => "411 Length Required", "PRECONDITION_FAILED" => "412 Precondition Failed", "SERVER_ERROR" => "500 Internal Server Error", "NOT_IMPLEMENTED" => "501 Method Not Implemented", "BAD_GATEWAY" => "502 Bad Gateway", "VARIANT_ALSO_VARIES" => "506 Variant Also Negotiates" } # :startdoc: # Synonym for ENV. def env_table ENV end # Synonym for $stdin. def stdinput $stdin end # Synonym for $stdout. def stdoutput $stdout end private :env_table, :stdinput, :stdoutput # Create an HTTP header block as a string. # # :call-seq: # http_header(content_type_string="text/html") # http_header(headers_hash) # # Includes the empty line that ends the header block. # # +content_type_string+:: # If this form is used, this string is the <tt>Content-Type</tt> # +headers_hash+:: # A Hash of header values. The following header keys are recognized: # # type:: The Content-Type header. Defaults to "text/html" # charset:: The charset of the body, appended to the Content-Type header. # nph:: A boolean value. If true, prepend protocol string and status # code, and date; and sets default values for "server" and # "connection" if not explicitly set. # status:: # The HTTP status code as a String, returned as the Status header. The # values are: # # OK:: 200 OK # PARTIAL_CONTENT:: 206 Partial Content # MULTIPLE_CHOICES:: 300 Multiple Choices # MOVED:: 301 Moved Permanently # REDIRECT:: 302 Found # NOT_MODIFIED:: 304 Not Modified # BAD_REQUEST:: 400 Bad Request # AUTH_REQUIRED:: 401 Authorization Required # FORBIDDEN:: 403 Forbidden # NOT_FOUND:: 404 Not Found # METHOD_NOT_ALLOWED:: 405 Method Not Allowed # NOT_ACCEPTABLE:: 406 Not Acceptable # LENGTH_REQUIRED:: 411 Length Required # PRECONDITION_FAILED:: 412 Precondition Failed # SERVER_ERROR:: 500 Internal Server Error # NOT_IMPLEMENTED:: 501 Method Not Implemented # BAD_GATEWAY:: 502 Bad Gateway # VARIANT_ALSO_VARIES:: 506 Variant Also Negotiates # # server:: The server software, returned as the Server header. # connection:: The connection type, returned as the Connection header (for # instance, "close". # length:: The length of the content that will be sent, returned as the # Content-Length header. # language:: The language of the content, returned as the Content-Language # header. # expires:: The time on which the current content expires, as a +Time+ # object, returned as the Expires header. # cookie:: # A cookie or cookies, returned as one or more Set-Cookie headers. The # value can be the literal string of the cookie; a CGI::Cookie object; # an Array of literal cookie strings or Cookie objects; or a hash all of # whose values are literal cookie strings or Cookie objects. # # These cookies are in addition to the cookies held in the # @output_cookies field. # # Other headers can also be set; they are appended as key: value. # # Examples: # # http_header # # Content-Type: text/html # # http_header("text/plain") # # Content-Type: text/plain # # http_header("nph" => true, # "status" => "OK", # == "200 OK" # # "status" => "200 GOOD", # "server" => ENV['SERVER_SOFTWARE'], # "connection" => "close", # "type" => "text/html", # "charset" => "iso-2022-jp", # # Content-Type: text/html; charset=iso-2022-jp # "length" => 103, # "language" => "ja", # "expires" => Time.now + 30, # "cookie" => [cookie1, cookie2], # "my_header1" => "my_value", # "my_header2" => "my_value") # # This method does not perform charset conversion. def http_header(options='text/html') if options.is_a?(String) content_type = options buf = _header_for_string(content_type) elsif options.is_a?(Hash) if options.size == 1 && options.has_key?('type') content_type = options['type'] buf = _header_for_string(content_type) else buf = _header_for_hash(options.dup) end else raise ArgumentError.new("expected String or Hash but got #{options.class}") end if defined?(MOD_RUBY) _header_for_modruby(buf) return '' else buf << EOL # empty line of separator return buf end end # http_header() # This method is an alias for #http_header, when HTML5 tag maker is inactive. # # NOTE: use #http_header to create HTTP header blocks, this alias is only # provided for backwards compatibility. # # Using #header with the HTML5 tag maker will create a <header> element. alias :header :http_header def _header_for_string(content_type) #:nodoc: buf = ''.dup if nph?() buf << "#{$CGI_ENV['SERVER_PROTOCOL'] || 'HTTP/1.0'} 200 OK#{EOL}" buf << "Date: #{CGI.rfc1123_date(Time.now)}#{EOL}" buf << "Server: #{$CGI_ENV['SERVER_SOFTWARE']}#{EOL}" buf << "Connection: close#{EOL}" end buf << "Content-Type: #{content_type}#{EOL}" if @output_cookies @output_cookies.each {|cookie| buf << "Set-Cookie: #{cookie}#{EOL}" } end return buf end # _header_for_string private :_header_for_string def _header_for_hash(options) #:nodoc: buf = ''.dup ## add charset to option['type'] options['type'] ||= 'text/html' charset = options.delete('charset') options['type'] += "; charset=#{charset}" if charset ## NPH options.delete('nph') if defined?(MOD_RUBY) if options.delete('nph') || nph?() protocol = $CGI_ENV['SERVER_PROTOCOL'] || 'HTTP/1.0' status = options.delete('status') status = HTTP_STATUS[status] || status || '200 OK' buf << "#{protocol} #{status}#{EOL}" buf << "Date: #{CGI.rfc1123_date(Time.now)}#{EOL}" options['server'] ||= $CGI_ENV['SERVER_SOFTWARE'] || '' options['connection'] ||= 'close' end ## common headers status = options.delete('status') buf << "Status: #{HTTP_STATUS[status] || status}#{EOL}" if status server = options.delete('server') buf << "Server: #{server}#{EOL}" if server connection = options.delete('connection') buf << "Connection: #{connection}#{EOL}" if connection type = options.delete('type') buf << "Content-Type: #{type}#{EOL}" #if type length = options.delete('length') buf << "Content-Length: #{length}#{EOL}" if length language = options.delete('language') buf << "Content-Language: #{language}#{EOL}" if language expires = options.delete('expires') buf << "Expires: #{CGI.rfc1123_date(expires)}#{EOL}" if expires ## cookie if cookie = options.delete('cookie') case cookie when String, Cookie buf << "Set-Cookie: #{cookie}#{EOL}" when Array arr = cookie arr.each {|c| buf << "Set-Cookie: #{c}#{EOL}" } when Hash hash = cookie hash.each_value {|c| buf << "Set-Cookie: #{c}#{EOL}" } end end if @output_cookies @output_cookies.each {|c| buf << "Set-Cookie: #{c}#{EOL}" } end ## other headers options.each do |key, value| buf << "#{key}: #{value}#{EOL}" end return buf end # _header_for_hash private :_header_for_hash def nph? #:nodoc: return /IIS\/(\d+)/ =~ $CGI_ENV['SERVER_SOFTWARE'] && $1.to_i < 5 end def _header_for_modruby(buf) #:nodoc: request = Apache::request buf.scan(/([^:]+): (.+)#{EOL}/o) do |name, value| $stderr.printf("name:%s value:%s\n", name, value) if $DEBUG case name when 'Set-Cookie' request.headers_out.add(name, value) when /^status$/i request.status_line = value request.status = value.to_i when /^content-type$/i request.content_type = value when /^content-encoding$/i request.content_encoding = value when /^location$/i request.status = 302 if request.status == 200 request.headers_out[name] = value else request.headers_out[name] = value end end request.send_http_header return '' end private :_header_for_modruby # Print an HTTP header and body to $DEFAULT_OUTPUT ($>) # # :call-seq: # cgi.out(content_type_string='text/html') # cgi.out(headers_hash) # # +content_type_string+:: # If a string is passed, it is assumed to be the content type. # +headers_hash+:: # This is a Hash of headers, similar to that used by #http_header. # +block+:: # A block is required and should evaluate to the body of the response. # # <tt>Content-Length</tt> is automatically calculated from the size of # the String returned by the content block. # # If <tt>ENV['REQUEST_METHOD'] == "HEAD"</tt>, then only the header # is output (the content block is still required, but it is ignored). # # If the charset is "iso-2022-jp" or "euc-jp" or "shift_jis" then the # content is converted to this charset, and the language is set to "ja". # # Example: # # cgi = CGI.new # cgi.out{ "string" } # # Content-Type: text/html # # Content-Length: 6 # # # # string # # cgi.out("text/plain") { "string" } # # Content-Type: text/plain # # Content-Length: 6 # # # # string # # cgi.out("nph" => true, # "status" => "OK", # == "200 OK" # "server" => ENV['SERVER_SOFTWARE'], # "connection" => "close", # "type" => "text/html", # "charset" => "iso-2022-jp", # # Content-Type: text/html; charset=iso-2022-jp # "language" => "ja", # "expires" => Time.now + (3600 * 24 * 30), # "cookie" => [cookie1, cookie2], # "my_header1" => "my_value", # "my_header2" => "my_value") { "string" } # # HTTP/1.1 200 OK # # Date: Sun, 15 May 2011 17:35:54 GMT # # Server: Apache 2.2.0 # # Connection: close # # Content-Type: text/html; charset=iso-2022-jp # # Content-Length: 6 # # Content-Language: ja # # Expires: Tue, 14 Jun 2011 17:35:54 GMT # # Set-Cookie: foo # # Set-Cookie: bar # # my_header1: my_value # # my_header2: my_value # # # # string def out(options = "text/html") # :yield: options = { "type" => options } if options.kind_of?(String) content = yield options["length"] = content.bytesize.to_s output = stdoutput output.binmode if defined? output.binmode output.print http_header(options) output.print content unless "HEAD" == env_table['REQUEST_METHOD'] end # Print an argument or list of arguments to the default output stream # # cgi = CGI.new # cgi.print # default: cgi.print == $DEFAULT_OUTPUT.print def print(*options) stdoutput.print(*options) end # Parse an HTTP query string into a hash of key=>value pairs. # # params = CGI.parse("query_string") # # {"name1" => ["value1", "value2", ...], # # "name2" => ["value1", "value2", ...], ... } # def self.parse(query) params = {} query.split(/[&;]/).each do |pairs| key, value = pairs.split('=',2).collect{|v| CGI.unescape(v) } next unless key params[key] ||= [] params[key].push(value) if value end params.default=[].freeze params end # Maximum content length of post data ##MAX_CONTENT_LENGTH = 2 * 1024 * 1024 # Maximum number of request parameters when multipart MAX_MULTIPART_COUNT = 128 # Mixin module that provides the following: # # 1. Access to the CGI environment variables as methods. See # documentation to the CGI class for a list of these variables. The # methods are exposed by removing the leading +HTTP_+ (if it exists) and # downcasing the name. For example, +auth_type+ will return the # environment variable +AUTH_TYPE+, and +accept+ will return the value # for +HTTP_ACCEPT+. # # 2. Access to cookies, including the cookies attribute. # # 3. Access to parameters, including the params attribute, and overloading # #[] to perform parameter value lookup by key. # # 4. The initialize_query method, for initializing the above # mechanisms, handling multipart forms, and allowing the # class to be used in "offline" mode. # module QueryExtension %w[ CONTENT_LENGTH SERVER_PORT ].each do |env| define_method(env.delete_prefix('HTTP_').downcase) do (val = env_table[env]) && Integer(val) end end %w[ AUTH_TYPE CONTENT_TYPE GATEWAY_INTERFACE PATH_INFO PATH_TRANSLATED QUERY_STRING REMOTE_ADDR REMOTE_HOST REMOTE_IDENT REMOTE_USER REQUEST_METHOD SCRIPT_NAME SERVER_NAME SERVER_PROTOCOL SERVER_SOFTWARE HTTP_ACCEPT HTTP_ACCEPT_CHARSET HTTP_ACCEPT_ENCODING HTTP_ACCEPT_LANGUAGE HTTP_CACHE_CONTROL HTTP_FROM HTTP_HOST HTTP_NEGOTIATE HTTP_PRAGMA HTTP_REFERER HTTP_USER_AGENT ].each do |env| define_method(env.delete_prefix('HTTP_').downcase) do env_table[env] end end # Get the raw cookies as a string. def raw_cookie env_table["HTTP_COOKIE"] end # Get the raw RFC2965 cookies as a string. def raw_cookie2 env_table["HTTP_COOKIE2"] end # Get the cookies as a hash of cookie-name=>Cookie pairs. attr_accessor :cookies # Get the parameters as a hash of name=>values pairs, where # values is an Array. attr_reader :params # Get the uploaded files as a hash of name=>values pairs attr_reader :files # Set all the parameters. def params=(hash) @params.clear @params.update(hash) end ## # Parses multipart form elements according to # http://www.w3.org/TR/html401/interact/forms.html#h-17.13.4.2 # # Returns a hash of multipart form parameters with bodies of type StringIO or # Tempfile depending on whether the multipart form element exceeds 10 KB # # params[name => body] # def read_multipart(boundary, content_length) ## read first boundary stdin = stdinput first_line = "--#{boundary}#{EOL}" content_length -= first_line.bytesize status = stdin.read(first_line.bytesize) raise EOFError.new("no content body") unless status raise EOFError.new("bad content body") unless first_line == status ## parse and set params params = {} @files = {} boundary_rexp = /--#{Regexp.quote(boundary)}(#{EOL}|--)/ boundary_size = "#{EOL}--#{boundary}#{EOL}".bytesize buf = ''.dup bufsize = 10 * 1024 max_count = MAX_MULTIPART_COUNT n = 0 tempfiles = [] while true (n += 1) < max_count or raise StandardError.new("too many parameters.") ## create body (StringIO or Tempfile) body = create_body(bufsize < content_length) tempfiles << body if defined?(Tempfile) && body.kind_of?(Tempfile) class << body if method_defined?(:path) alias local_path path else def local_path nil end end attr_reader :original_filename, :content_type end ## find head and boundary head = nil separator = EOL * 2 until head && matched = boundary_rexp.match(buf) if !head && pos = buf.index(separator) len = pos + EOL.bytesize head = buf[0, len] buf = buf[(pos+separator.bytesize)..-1] else if head && buf.size > boundary_size len = buf.size - boundary_size body.print(buf[0, len]) buf[0, len] = '' end c = stdin.read(bufsize < content_length ? bufsize : content_length) raise EOFError.new("bad content body") if c.nil? || c.empty? buf << c content_length -= c.bytesize end end ## read to end of boundary m = matched len = m.begin(0) s = buf[0, len] if s =~ /(\r?\n)\z/ s = buf[0, len - $1.bytesize] end body.print(s) buf = buf[m.end(0)..-1] boundary_end = m[1] content_length = -1 if boundary_end == '--' ## reset file cursor position body.rewind ## original filename /Content-Disposition:.* filename=(?:"(.*?)"|([^;\r\n]*))/i.match(head) filename = $1 || $2 || ''.dup filename = CGI.unescape(filename) if unescape_filename?() body.instance_variable_set(:@original_filename, filename) ## content type /Content-Type: (.*)/i.match(head) (content_type = $1 || ''.dup).chomp! body.instance_variable_set(:@content_type, content_type) ## query parameter name /Content-Disposition:.* name=(?:"(.*?)"|([^;\r\n]*))/i.match(head) name = $1 || $2 || '' if body.original_filename.empty? value=body.read.dup.force_encoding(@accept_charset) body.close! if defined?(Tempfile) && body.kind_of?(Tempfile) (params[name] ||= []) << value unless value.valid_encoding? if @accept_charset_error_block @accept_charset_error_block.call(name,value) else raise InvalidEncoding,"Accept-Charset encoding error" end end class << params[name].last;self;end.class_eval do define_method(:read){self} define_method(:original_filename){""} define_method(:content_type){""} end else (params[name] ||= []) << body @files[name]=body end ## break loop break if content_length == -1 end raise EOFError, "bad boundary end of body part" unless boundary_end =~ /--/ params.default = [] params rescue Exception if tempfiles tempfiles.each {|t| if t.path t.close! end } end raise end # read_multipart private :read_multipart def create_body(is_large) #:nodoc: if is_large require 'tempfile' body = Tempfile.new('CGI', encoding: Encoding::ASCII_8BIT) else begin require 'stringio' body = StringIO.new("".b) rescue LoadError require 'tempfile' body = Tempfile.new('CGI', encoding: Encoding::ASCII_8BIT) end end body.binmode if defined? body.binmode return body end def unescape_filename? #:nodoc: user_agent = $CGI_ENV['HTTP_USER_AGENT'] return false unless user_agent return /Mac/i.match(user_agent) && /Mozilla/i.match(user_agent) && !/MSIE/i.match(user_agent) end # offline mode. read name=value pairs on standard input. def read_from_cmdline require "shellwords" string = unless ARGV.empty? ARGV.join(' ') else if STDIN.tty? STDERR.print( %|(offline mode: enter name=value pairs on standard input)\n| ) end array = readlines rescue nil if not array.nil? array.join(' ').gsub(/\n/n, '') else "" end end.gsub(/\\=/n, '%3D').gsub(/\\&/n, '%26') words = Shellwords.shellwords(string) if words.find{|x| /=/n.match(x) } words.join('&') else words.join('+') end end private :read_from_cmdline # A wrapper class to use a StringIO object as the body and switch # to a TempFile when the passed threshold is passed. # Initialize the data from the query. # # Handles multipart forms (in particular, forms that involve file uploads). # Reads query parameters in the @params field, and cookies into @cookies. def initialize_query() if ("POST" == env_table['REQUEST_METHOD']) and %r|\Amultipart/form-data.*boundary=\"?([^\";,]+)\"?| =~ env_table['CONTENT_TYPE'] current_max_multipart_length = @max_multipart_length.respond_to?(:call) ? @max_multipart_length.call : @max_multipart_length raise StandardError.new("too large multipart data.") if env_table['CONTENT_LENGTH'].to_i > current_max_multipart_length boundary = $1.dup @multipart = true @params = read_multipart(boundary, Integer(env_table['CONTENT_LENGTH'])) else @multipart = false @params = CGI.parse( case env_table['REQUEST_METHOD'] when "GET", "HEAD" if defined?(MOD_RUBY) Apache::request.args or "" else env_table['QUERY_STRING'] or "" end when "POST" stdinput.binmode if defined? stdinput.binmode stdinput.read(Integer(env_table['CONTENT_LENGTH'])) or '' else read_from_cmdline end.dup.force_encoding(@accept_charset) ) unless Encoding.find(@accept_charset) == Encoding::ASCII_8BIT @params.each do |key,values| values.each do |value| unless value.valid_encoding? if @accept_charset_error_block @accept_charset_error_block.call(key,value) else raise InvalidEncoding,"Accept-Charset encoding error" end end end end end end @cookies = CGI::Cookie.parse((env_table['HTTP_COOKIE'] or env_table['COOKIE'])) end private :initialize_query # Returns whether the form contained multipart/form-data def multipart? @multipart end # Get the value for the parameter with a given key. # # If the parameter has multiple values, only the first will be # retrieved; use #params to get the array of values. def [](key) params = @params[key] return '' unless params value = params[0] if @multipart if value return value elsif defined? StringIO StringIO.new("".b) else Tempfile.new("CGI",encoding: Encoding::ASCII_8BIT) end else str = if value then value.dup else "" end str end end # Return all query parameter names as an array of String. def keys(*args) @params.keys(*args) end # Returns true if a given query string parameter exists. def has_key?(*args) @params.has_key?(*args) end alias key? has_key? alias include? has_key? end # QueryExtension # Exception raised when there is an invalid encoding detected class InvalidEncoding < Exception; end # @@accept_charset is default accept character set. # This default value default is "UTF-8" # If you want to change the default accept character set # when create a new CGI instance, set this: # # CGI.accept_charset = "EUC-JP" # @@accept_charset="UTF-8" if false # needed for rdoc? # Return the accept character set for all new CGI instances. def self.accept_charset @@accept_charset end # Set the accept character set for all new CGI instances. def self.accept_charset=(accept_charset) @@accept_charset=accept_charset end # Return the accept character set for this CGI instance. attr_reader :accept_charset # @@max_multipart_length is the maximum length of multipart data. # The default value is 128 * 1024 * 1024 bytes # # The default can be set to something else in the CGI constructor, # via the :max_multipart_length key in the option hash. # # See CGI.new documentation. # @@max_multipart_length= 128 * 1024 * 1024 # Create a new CGI instance. # # :call-seq: # CGI.new(tag_maker) { block } # CGI.new(options_hash = {}) { block } # # # <tt>tag_maker</tt>:: # This is the same as using the +options_hash+ form with the value <tt>{ # :tag_maker => tag_maker }</tt> Note that it is recommended to use the # +options_hash+ form, since it also allows you specify the charset you # will accept. # <tt>options_hash</tt>:: # A Hash that recognizes three options: # # <tt>:accept_charset</tt>:: # specifies encoding of received query string. If omitted, # <tt>@@accept_charset</tt> is used. If the encoding is not valid, a # CGI::InvalidEncoding will be raised. # # Example. Suppose <tt>@@accept_charset</tt> is "UTF-8" # # when not specified: # # cgi=CGI.new # @accept_charset # => "UTF-8" # # when specified as "EUC-JP": # # cgi=CGI.new(:accept_charset => "EUC-JP") # => "EUC-JP" # # <tt>:tag_maker</tt>:: # String that specifies which version of the HTML generation methods to # use. If not specified, no HTML generation methods will be loaded. # # The following values are supported: # # "html3":: HTML 3.x # "html4":: HTML 4.0 # "html4Tr":: HTML 4.0 Transitional # "html4Fr":: HTML 4.0 with Framesets # "html5":: HTML 5 # # <tt>:max_multipart_length</tt>:: # Specifies maximum length of multipart data. Can be an Integer scalar or # a lambda, that will be evaluated when the request is parsed. This # allows more complex logic to be set when determining whether to accept # multipart data (e.g. consult a registered users upload allowance) # # Default is 128 * 1024 * 1024 bytes # # cgi=CGI.new(:max_multipart_length => 268435456) # simple scalar # # cgi=CGI.new(:max_multipart_length => -> {check_filesystem}) # lambda # # <tt>block</tt>:: # If provided, the block is called when an invalid encoding is # encountered. For example: # # encoding_errors={} # cgi=CGI.new(:accept_charset=>"EUC-JP") do |name,value| # encoding_errors[name] = value # end # # Finally, if the CGI object is not created in a standard CGI call # environment (that is, it can't locate REQUEST_METHOD in its environment), # then it will run in "offline" mode. In this mode, it reads its parameters # from the command line or (failing that) from standard input. Otherwise, # cookies and other parameters are parsed automatically from the standard # CGI locations, which varies according to the REQUEST_METHOD. def initialize(options = {}, &block) # :yields: name, value @accept_charset_error_block = block_given? ? block : nil @options={ :accept_charset=>@@accept_charset, :max_multipart_length=>@@max_multipart_length } case options when Hash @options.merge!(options) when String @options[:tag_maker]=options end @accept_charset=@options[:accept_charset] @max_multipart_length=@options[:max_multipart_length] if defined?(MOD_RUBY) && !ENV.key?("GATEWAY_INTERFACE") Apache.request.setup_cgi_env end extend QueryExtension @multipart = false initialize_query() # set @params, @cookies @output_cookies = nil @output_hidden = nil case @options[:tag_maker] when "html3" require_relative 'html' extend Html3 extend HtmlExtension when "html4" require_relative 'html' extend Html4 extend HtmlExtension when "html4Tr" require_relative 'html' extend Html4Tr extend HtmlExtension when "html4Fr" require_relative 'html' extend Html4Tr extend Html4Fr extend HtmlExtension when "html5" require_relative 'html' extend Html5 extend HtmlExtension end end end # class CGI