cgihandler.rb

# frozen_string_literal: true
#
# cgihandler.rb -- CGIHandler Class
#
# Author: IPR -- Internet Programming with Ruby -- writers
# Copyright (c) 2001 TAKAHASHI Masayoshi, GOTOU Yuuzou
# Copyright (c) 2002 Internet Programming with Ruby writers. All rights
# reserved.
#
# $IPR: cgihandler.rb,v 1.27 2003/03/21 19:56:01 gotoyuzo Exp $

require 'rbconfig'
require 'tempfile'
require_relative '../config'
require_relative 'abstract'

module WEBrick
  module HTTPServlet

    ##
    # Servlet for handling CGI scripts
    #
    # Example:
    #
    #  server.mount('/cgi/my_script', WEBrick::HTTPServlet::CGIHandler,
    #               '/path/to/my_script')

    class CGIHandler < AbstractServlet
      Ruby = RbConfig.ruby # :nodoc:
      CGIRunner = "\"#{Ruby}\" \"#{WEBrick::Config::LIBDIR}/httpservlet/cgi_runner.rb\"" # :nodoc:
      CGIRunnerArray = [Ruby, "#{WEBrick::Config::LIBDIR}/httpservlet/cgi_runner.rb".freeze].freeze # :nodoc:

      ##
      # Creates a new CGI script servlet for the script at +name+

      def initialize(server, name)
        super(server, name)
        @script_filename = name
        @tempdir = server[:TempDir]
        interpreter = server[:CGIInterpreter]
        if interpreter.is_a?(Array)
          @cgicmd = CGIRunnerArray + interpreter
        else
          @cgicmd = "#{CGIRunner} #{interpreter}"
        end
      end

      # :stopdoc:

      def do_GET(req, res)
        cgi_in = IO::popen(@cgicmd, "wb")
        cgi_out = Tempfile.new("webrick.cgiout.", @tempdir, mode: IO::BINARY)
        cgi_out.set_encoding("ASCII-8BIT")
        cgi_err = Tempfile.new("webrick.cgierr.", @tempdir, mode: IO::BINARY)
        cgi_err.set_encoding("ASCII-8BIT")
        begin
          cgi_in.sync = true
          meta = req.meta_vars
          meta["SCRIPT_FILENAME"] = @script_filename
          meta["PATH"] = @config[:CGIPathEnv]
          meta.delete("HTTP_PROXY")
          if /mswin|bccwin|mingw/ =~ RUBY_PLATFORM
            meta["SystemRoot"] = ENV["SystemRoot"]
          end
          dump = Marshal.dump(meta)

          cgi_in.write("%8d" % cgi_out.path.bytesize)
          cgi_in.write(cgi_out.path)
          cgi_in.write("%8d" % cgi_err.path.bytesize)
          cgi_in.write(cgi_err.path)
          cgi_in.write("%8d" % dump.bytesize)
          cgi_in.write(dump)

          req.body { |chunk| cgi_in.write(chunk) }
        ensure
          cgi_in.close
          status = $?.exitstatus
          sleep 0.1 if /mswin|bccwin|mingw/ =~ RUBY_PLATFORM
          data = cgi_out.read
          cgi_out.close(true)
          if errmsg = cgi_err.read
            if errmsg.bytesize > 0
              @logger.error("CGIHandler: #{@script_filename}:\n" + errmsg)
            end
          end
          cgi_err.close(true)
        end

        if status != 0
          @logger.error("CGIHandler: #{@script_filename} exit with #{status}")
        end

        data = "" unless data
        raw_header, body = data.split(/^[\xd\xa]+/, 2)
        raise HTTPStatus::InternalServerError,
          "Premature end of script headers: #{@script_filename}" if body.nil?

        begin
          header = HTTPUtils::parse_header(raw_header,
            header_line_regexp: REGEXP_CGI_HEADER_LINE ,
            continued_header_line_regexp: REGEXP_CONTINUED_CGI_HEADER_LINE)
          if /^(\d+)/ =~ header['status'][0]
            res.status = $1.to_i
            header.delete('status')
          end
          if header.has_key?('location')
            # RFC 3875 6.2.3, 6.2.4
            res.status = 302 unless (300...400) === res.status
          end
          if header.has_key?('set-cookie')
            header['set-cookie'].each{|k|
              res.cookies << Cookie.parse_set_cookie(k)
            }
            header.delete('set-cookie')
          end
          header.each{|key, val| res[key] = val.join(", ") }
        rescue => ex
          raise HTTPStatus::InternalServerError, ex.message
        end
        res.body = body
      end
      alias do_POST do_GET

      REGEXP_CGI_HEADER_LINE = /^([A-Za-z0-9!\#$%&'*+\-.^_`|~]+):([^\r\n\0]*?)\r?\n\z/m
      REGEXP_CONTINUED_CGI_HEADER_LINE = /^[ \t]+([^\r\n\0]*?)\r?\n/m
      private_constant :REGEXP_CGI_HEADER_LINE, :REGEXP_CONTINUED_CGI_HEADER_LINE

      # :startdoc:
    end

  end
end