Re: [PATCH] Resolv and TTL

On 10 Jun 2005, at 02:39, Eric Hodel wrote:

> I would like to retrieve the TTL values from Resolv, but they seem  
> to get thrown away long before they're near the public API, and  
> digging through the guts of Resolv::DNS would only result in much  
> duplicate code.
>
> The following patch adds #ttl to Resolv::DNS::Resource.  I also  
> changed #== and #hash because the TTL changes every time a new  
> resource is requested.

Has anyone had a chance to review this patch?

> Index: lib/resolv.rb
> ===================================================================
> RCS file: /src/ruby/lib/resolv.rb,v
> retrieving revision 1.29
> diff -u -r1.29 resolv.rb
> --- lib/resolv.rb       9 Jun 2005 22:47:35 -0000       1.29
> +++ lib/resolv.rb       10 Jun 2005 08:57:09 -0000
> @@ -1406,7 +1406,10 @@
>            name = self.get_name
>            type, klass, ttl = self.get_unpack('nnN')
>            typeclass = Resource.get_class(type, klass)
> -          return name, ttl, self.get_length16  
> {typeclass.decode_rdata(self)}
> +          res = self.get_length16 { typeclass.decode_rdata self }
> +          res.instance_variable_set :@ttl, ttl
> +
> +          return name, ttl, res
>          end
>        end
>      end
> @@ -1429,6 +1432,11 @@
>
>      class Resource < Query
>
> +      ##
> +      # Remaining Time To Live for this Resource.
> +
> +      attr_reader :ttl
> +
>        ClassHash = {} # :nodoc:
>
>        def encode_rdata(msg) # :nodoc:
> @@ -1440,10 +1448,13 @@
>        end
>
>        def ==(other) # :nodoc:
> -        return self.class == other.class &&
> -          self.instance_variables == other.instance_variables &&
> -          self.instance_variables.collect {|name|  
> self.instance_eval name} ==
> -            other.instance_variables.collect {|name|  
> other.instance_eval name}
> +        return false unless self.class == other.class
> +        s_ivars = self.instance_variables.reject { |name| name ==  
> "@ttl" }
> +        o_ivars = other.instance_variables.reject { |name| name ==  
> "@ttl" }
> +
> +        return s_ivars == o_ivars &&
> +          s_ivars.collect {|name| self.instance_eval name} ==
> +            o_ivars.collect {|name| other.instance_eval name}
>        end
>
>        def eql?(other) # :nodoc:
> @@ -1452,7 +1463,7 @@
>
>        def hash # :nodoc:
>          h = 0
> -        self.instance_variables.each {|name|
> +        self.instance_variables.reject { |name| name ==  
> "@ttl" }.each {|name|
>            h ^= self.instance_eval("#{name}.hash")
>          }
>          return h
>
>
>

-- 
Eric Hodel - [e-mail] - http://segment7.net
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