xapian-core/matcher/remotesubmatch.h

   1 /** @file
   2  *  @brief SubMatch class for a remote database.
   3  */
   4 /* Copyright (C) 2006,2007,2009,2011,2014,2015 Olly Betts
   5  * Copyright (C) 2007,2008 Lemur Consulting Ltd
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 2 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
  20  */
  21
  22 #ifndef XAPIAN_INCLUDED_REMOTESUBMATCH_H
  23 #define XAPIAN_INCLUDED_REMOTESUBMATCH_H
  24
  25 #include "submatch.h"
  26 #include "backends/remote/remote-database.h"
  27 #include "xapian/weight.h"
  28
  29 namespace Xapian {
  30     class MatchSpy;
  31 }
  32
  33 /// Class for performing matching on a remote database.
  34 class RemoteSubMatch : public SubMatch {
  35     /// Don't allow assignment.
  36     void operator=(const RemoteSubMatch &);
  37
  38     /// Don't allow copying.
  39     RemoteSubMatch(const RemoteSubMatch &);
  40
  41     /// The remote database.
  42     RemoteDatabase *db;
  43
  44     /** Is the sort order such the relevance decreases down the MSet?
  45      *
  46      *  This is true for sort_by_relevance and sort_by_relevance_then_value.
  47      */
  48     bool decreasing_relevance;
  49
  50     /// uncollapsed_upper_bound from the remote MSet.
  51     Xapian::doccount uncollapsed_upper_bound;
  52
  53     /// The factor to use to convert weights to percentages.
  54     double percent_factor;
  55
  56     /// The matchspies to use.
  57     const vector<Xapian::Internal::opt_intrusive_ptr<Xapian::MatchSpy>> & matchspies;
  58
  59   public:
  60     /// Constructor.
  61     RemoteSubMatch(RemoteDatabase *db_,
  62                    bool decreasing_relevance_,
  63                    const vector<Xapian::Internal::opt_intrusive_ptr<Xapian::MatchSpy>> & matchspies);
  64
  65     /// Fetch and collate statistics.
  66     bool prepare_match(bool nowait, Xapian::Weight::Internal & total_stats);
  67
  68     /// Start the match.
  69     void start_match(Xapian::doccount first,
  70                      Xapian::doccount maxitems,
  71                      Xapian::doccount check_at_least,
  72                      Xapian::Weight::Internal & total_stats);
  73
  74     /// Get PostList.
  75     PostList * get_postlist(MultiMatch * matcher,
  76                             Xapian::termcount* total_subqs_ptr,
  77                             Xapian::Weight::Internal& total_stats);
  78
  79     /// Get uncollapsed_upper_bound from the remote MSet.
  80     Xapian::doccount get_uncollapsed_upper_bound() const {
  81         return uncollapsed_upper_bound;
  82     }
  83
  84     /// Get percentage factor - only valid after get_postlist().
  85     double get_percent_factor() const { return percent_factor; }
  86
  87     /// Short-cut for single remote match.
  88     void get_mset(Xapian::MSet & mset) { db->get_mset(mset, matchspies); }
  89 };
  90
  91 #endif /* XAPIAN_INCLUDED_REMOTESUBMATCH_H */