Class: Resolv::DNS::Config
- Inherits:
-
Object
- Object
- Resolv::DNS::Config
show all
- Defined in:
- lib/resolv.rb
Overview
Defined Under Namespace
Classes: NXDomain, OtherResolvError
Constant Summary
collapse
- InitialTimeout =
5
Class Method Summary
collapse
Instance Method Summary
collapse
Constructor Details
#initialize(config_info = nil) ⇒ Config
Returns a new instance of Config.
808
809
810
811
812
|
# File 'lib/resolv.rb', line 808
def initialize(config_info=nil)
@mutex = Mutex.new
@config_info = config_info
@initialized = nil
end
|
Class Method Details
.default_config_hash(filename = "/etc/resolv.conf")) ⇒ Object
848
849
850
851
852
853
854
855
856
857
858
859
860
861
|
# File 'lib/resolv.rb', line 848
def Config.default_config_hash(filename="/etc/resolv.conf")
if File.exist? filename
config_hash = Config.parse_resolv_conf(filename)
else
if /mswin32|cygwin|mingw|bccwin/ =~ RUBY_PLATFORM
require 'win32/resolv'
search, nameserver = Win32::Resolv.get_resolv_info
config_hash = {}
config_hash[:nameserver] = nameserver if nameserver
config_hash[:search] = [search].flatten if search
end
end
config_hash
end
|
.parse_resolv_conf(filename) ⇒ Object
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
|
# File 'lib/resolv.rb', line 814
def Config.parse_resolv_conf(filename)
nameserver = []
search = nil
ndots = 1
open(filename) {|f|
f.each {|line|
line.sub!(/[#;].*/, '')
keyword, *args = line.split(/\s+/)
args.each { |arg|
arg.untaint
}
next unless keyword
case keyword
when 'nameserver'
nameserver += args
when 'domain'
next if args.empty?
search = [args[0]]
when 'search'
next if args.empty?
search = args
when 'options'
args.each {|arg|
case arg
when /\Andots:(\d+)\z/
ndots = $1.to_i
end
}
end
}
}
return { :nameserver => nameserver, :search => search, :ndots => ndots }
end
|
Instance Method Details
#generate_candidates(name) ⇒ Object
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
|
# File 'lib/resolv.rb', line 936
def generate_candidates(name)
candidates = nil
name = Name.create(name)
if name.absolute?
candidates = [name]
else
if @ndots <= name.length - 1
candidates = [Name.new(name.to_a)]
else
candidates = []
end
candidates.concat(@search.map {|domain| Name.new(name.to_a + domain)})
end
return candidates
end
|
#generate_timeouts ⇒ Object
954
955
956
957
958
959
960
|
# File 'lib/resolv.rb', line 954
def generate_timeouts
ts = [InitialTimeout]
ts << ts[-1] * 2 / @nameserver.length
ts << ts[-1] * 2
ts << ts[-1] * 2
return ts
end
|
#lazy_initialize ⇒ Object
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
|
# File 'lib/resolv.rb', line 863
def lazy_initialize
@mutex.synchronize {
unless @initialized
@nameserver = []
@search = nil
@ndots = 1
case @config_info
when nil
config_hash = Config.default_config_hash
when String
config_hash = Config.parse_resolv_conf(@config_info)
when Hash
config_hash = @config_info.dup
if String === config_hash[:nameserver]
config_hash[:nameserver] = [config_hash[:nameserver]]
end
if String === config_hash[:search]
config_hash[:search] = [config_hash[:search]]
end
else
raise ArgumentError.new("invalid resolv configuration: #{@config_info.inspect}")
end
@nameserver = config_hash[:nameserver] if config_hash.include? :nameserver
@search = config_hash[:search] if config_hash.include? :search
@ndots = config_hash[:ndots] if config_hash.include? :ndots
@nameserver = ['0.0.0.0'] if @nameserver.empty?
if @search
@search = @search.map {|arg| Label.split(arg) }
else
hostname = Socket.gethostname
if /\./ =~ hostname
@search = [Label.split($')]
else
@search = [[]]
end
end
if !@nameserver.kind_of?(Array) ||
!@nameserver.all? {|ns| String === ns }
raise ArgumentError.new("invalid nameserver config: #{@nameserver.inspect}")
end
if !@search.kind_of?(Array) ||
!@search.all? {|ls| ls.all? {|l| Label::Str === l } }
raise ArgumentError.new("invalid search config: #{@search.inspect}")
end
if !@ndots.kind_of?(Integer)
raise ArgumentError.new("invalid ndots config: #{@ndots.inspect}")
end
@initialized = true
end
}
self
end
|
#nameserver_port ⇒ Object
930
931
932
933
934
|
# File 'lib/resolv.rb', line 930
def nameserver_port
lazy_initialize
@nameserver_port ||= @nameserver.map {|i| [i, Port] }
@nameserver_port
end
|
#resolv(name) ⇒ Object
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
|
# File 'lib/resolv.rb', line 962
def resolv(name)
candidates = generate_candidates(name)
timeouts = generate_timeouts
begin
candidates.each {|candidate|
begin
timeouts.each {|tout|
@nameserver.each {|nameserver|
begin
yield candidate, tout, nameserver
rescue ResolvTimeout
end
}
}
raise ResolvError.new("DNS resolv timeout: #{name}")
rescue NXDomain
end
}
rescue ResolvError
end
end
|
#single? ⇒ Boolean
921
922
923
924
925
926
927
928
|
# File 'lib/resolv.rb', line 921
def single?
lazy_initialize
if @nameserver.length == 1
return @nameserver[0]
else
return nil
end
end
|