In Files

  • resolv.rb

Resolv::DNS

Public Class Methods

new(config_info=nil) click to toggle source
 
               # File resolv.rb, line 386
def initialize(config_info=nil)
  @mutex = Mutex.new
  @config = Config.new(config_info)
  @initialized = nil
end
            
open(*args) click to toggle source
 
               # File resolv.rb, line 376
def self.open(*args)
  dns = new(*args)
  return dns unless block_given?
  begin
    yield dns
  ensure
    dns.close
  end
end
            

Public Instance Methods

close() click to toggle source
 
               # File resolv.rb, line 402
def close
  @mutex.synchronize {
    if @initialized
      @initialized = false
    end
  }
end
            
each_address(name) click to toggle source
 
               # File resolv.rb, line 421
def each_address(name)
  each_resource(name, Resource::IN::A) {|resource| yield resource.address}
end
            
each_name(address) click to toggle source
 
               # File resolv.rb, line 436
def each_name(address)
  case address
  when Name
    ptr = address
  when IPv4::Regex
    ptr = IPv4.create(address).to_name
  when IPv6::Regex
    ptr = IPv6.create(address).to_name
  else
    raise ResolvError.new("cannot interpret as address: #{address}")
  end
  each_resource(ptr, Resource::IN::PTR) {|resource| yield resource.name}
end
            
each_resource(name, typeclass, &proc) click to toggle source
 
               # File resolv.rb, line 461
def each_resource(name, typeclass, &proc)
  lazy_initialize
  requester = make_requester
  senders = {}
  begin
    @config.resolv(name) {|candidate, tout, nameserver|
      msg = Message.new
      msg.rd = 1
      msg.add_question(candidate, typeclass)
      unless sender = senders[[candidate, nameserver]]
        sender = senders[[candidate, nameserver]] =
          requester.sender(msg, candidate, nameserver)
      end
      reply, reply_name = requester.request(sender, tout)
      case reply.rcode
      when RCode::NoError
        extract_resources(reply, reply_name, typeclass, &proc)
        return
      when RCode::NXDomain
        raise Config::NXDomain.new(reply_name.to_s)
      else
        raise Config::OtherResolvError.new(reply_name.to_s)
      end
    }
  ensure
    requester.close
  end
end
            
extract_resources(msg, name, typeclass) click to toggle source
 
               # File resolv.rb, line 498
def extract_resources(msg, name, typeclass)
  if typeclass < Resource::ANY
    n0 = Name.create(name)
    msg.each_answer {|n, ttl, data|
      yield data if n0 == n
    }
  end
  yielded = false
  n0 = Name.create(name)
  msg.each_answer {|n, ttl, data|
    if n0 == n
      case data
      when typeclass
        yield data
        yielded = true
      when Resource::CNAME
        n0 = data.name
      end
    end
  }
  return if yielded
  msg.each_answer {|n, ttl, data|
    if n0 == n
      case data
      when typeclass
        yield data
      end
    end
  }
end
            
getaddress(name) click to toggle source
 
               # File resolv.rb, line 410
def getaddress(name)
  each_address(name) {|address| return address}
  raise ResolvError.new("DNS result has no information for #{name}")
end
            
getaddresses(name) click to toggle source
 
               # File resolv.rb, line 415
def getaddresses(name)
  ret = []
  each_address(name) {|address| ret << address}
  return ret
end
            
getname(address) click to toggle source
 
               # File resolv.rb, line 425
def getname(address)
  each_name(address) {|name| return name}
  raise ResolvError.new("DNS result has no information for #{address}")
end
            
getnames(address) click to toggle source
 
               # File resolv.rb, line 430
def getnames(address)
  ret = []
  each_name(address) {|name| ret << name}
  return ret
end
            
getresource(name, typeclass) click to toggle source
 
               # File resolv.rb, line 450
def getresource(name, typeclass)
  each_resource(name, typeclass) {|resource| return resource}
  raise ResolvError.new("DNS result has no information for #{name}")
end
            
getresources(name, typeclass) click to toggle source
 
               # File resolv.rb, line 455
def getresources(name, typeclass)
  ret = []
  each_resource(name, typeclass) {|resource| ret << resource}
  return ret
end
            
lazy_initialize() click to toggle source
 
               # File resolv.rb, line 392
def lazy_initialize
  @mutex.synchronize {
    unless @initialized
      @config.lazy_initialize
      @initialized = true
    end
  }
  self
end