BIND 10 #1747: refactor auth::Query so it's reusable

[BIND 10 Development]

#1747: refactor auth::Query so it's reusable
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                   Reporter:         |                 Owner:  jinmei
  jinmei                             |                Status:  reviewing
                       Type:  task   |             Milestone:
                   Priority:  high   |  Sprint-20120320
                  Component:         |            Resolution:
  b10-auth                           |             Sensitive:  0
                   Keywords:         |           Sub-Project:  DNS
            Defect Severity:  N/A    |  Estimated Difficulty:  4
Feature Depending on Ticket:  auth   |           Total Hours:  2.66
  performance                        |
        Add Hours to Ticket:  0      |
                  Internal?:  0      |
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Changes (by jelte):

 * owner:  jelte => jinmei


Comment:

 Replying to [comment:10 jinmei]:
 > Replying to [comment:9 jelte]:
 >
 > The revised version looks basically okay and ready for merge.  One
 > final suggestion: I'd reset datasrc_client_/qname_/qtype_/response_ to
 > NULL in reset().
 >

 ack, done

 > > Replying to [comment:7 jinmei]:
 > >
 > > The cleaner could also be initialized as the first part of process().
 I did think of such an approach, but as the object of this exercise was to
 reduce object allocation I was hesitant to do so (though this one would
 probably not be much overhead).
 >
 > The construction overhead of this `QueryCleaner` object should be
 > essentially nothing more than this:
 > {{{#!c++
 > Query& query_ref = query_;
 > }}}
 >
 > Anyway,
 > so I'm okay with deferring it.  Would you open a ticket for that?
 >

 crap it, that would almost have been more work than actually doing it :p

 Ok, added a private class QueryCleaner; which is initialized first thing
 in process(). Removed the other calls to vector::clear() and
 query::reset(). The multi-query tests should already show that this
 cleaner class is used and works (not sure whether it is worth it adding
 other methods to inspect the cleaner object is used).

 >
 > As long as the reserved space is sufficient, reallocation shouldn't
 > happen run-time, so unless we repeatedly build a response containing a
 > crazy number of RRsets, reallocation shouldn't happen again so soon.
 > But it's probably less likely to happen in the first place anyway (we
 > could have a crazy number of *RRs*, but it would be very unlikely to
 > include a large number of *RRsets*).  So I'm okay with skipping this
 > cleanup.  At least I'm okay with deferring it.

 created ticket #1777

 Passing back for a final look at those changes :)

-- 
Ticket URL: <http://bind10.isc.org/ticket/1747#comment:13>
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