port_prober.rb

# frozen_string_literal: true

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#
#   http://www.apache.org/licenses/LICENSE-2.0
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module Selenium
  module WebDriver
    class PortProber
      def self.above(port)
        port += 1 until free? port
        port
      end

      IGNORED_ERRORS = [Errno::EADDRNOTAVAIL, Errno::EAFNOSUPPORT].tap { |arr|
        arr << Errno::EBADF if Platform.cygwin?
        arr << Errno::EACCES if Platform.windows?
      }.freeze

      def self.free?(port)
        Platform.interfaces.each do |host|
          TCPServer.new(host, port).close
        rescue *IGNORED_ERRORS => e
          WebDriver.logger.debug("port prober could not bind to #{host}:#{port} (#{e.message})", id: :driver_service)
          # ignored - some machines appear unable to bind to some of their interfaces
        end

        true
      rescue SocketError, Errno::EADDRINUSE
        false
      end
    end # PortProber
  end # WebDriver
end # Selenium