xapian-core/api/valueiterator.cc

   1 /** @file valueiterator.cc
   2  *  @brief Class for iterating over document values.
   3  */
   4 /* Copyright (C) 2008,2009,2011,2013 Olly Betts
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
  19  */
  20
  21 #include <config.h>
  22
  23 #include "xapian/valueiterator.h"
  24
  25 #include "debuglog.h"
  26 #include "omassert.h"
  27 #include "backends/valuelist.h"
  28
  29 using namespace std;
  30
  31 namespace Xapian {
  32
  33 void
  34 ValueIterator::decref()
  35 {
  36     Assert(internal);
  37     if (--internal->_refs == 0)
  38         delete internal;
  39 }
  40
  41 ValueIterator::ValueIterator(Internal *internal_) : internal(internal_)
  42 {
  43     LOGCALL_CTOR(API, "ValueIterator", internal_);
  44     if (!internal)
  45         return;
  46     ++internal->_refs;
  47     try {
  48         internal->next();
  49     } catch (...) {
  50         // The destructor only runs if the constructor completes, so we have to
  51         // take care of cleaning up for ourselves here.
  52         decref();
  53         throw;
  54     }
  55     if (internal->at_end()) {
  56         decref();
  57         internal = NULL;
  58     }
  59 }
  60
  61 ValueIterator::ValueIterator(const ValueIterator & o)
  62     : internal(o.internal)
  63 {
  64     LOGCALL_CTOR(API, "ValueIterator", o);
  65     if (internal)
  66         ++internal->_refs;
  67 }
  68
  69 ValueIterator &
  70 ValueIterator::operator=(const ValueIterator & o)
  71 {
  72     LOGCALL(API, ValueIterator &, "ValueIterator::operator=", o);
  73     if (o.internal)
  74         ++o.internal->_refs;
  75     if (internal)
  76         decref();
  77     internal = o.internal;
  78     RETURN(*this);
  79 }
  80
  81 string
  82 ValueIterator::operator*() const
  83 {
  84     LOGCALL(API, string, "ValueIterator::operator*", NO_ARGS);
  85     Assert(internal);
  86     RETURN(internal->get_value());
  87 }
  88
  89 ValueIterator &
  90 ValueIterator::operator++()
  91 {
  92     LOGCALL(API, ValueIterator &, "ValueIterator::operator++", NO_ARGS);
  93     Assert(internal);
  94     internal->next();
  95     if (internal->at_end()) {
  96         decref();
  97         internal = NULL;
  98     }
  99     RETURN(*this);
 100 }
 101
 102 Xapian::docid
 103 ValueIterator::get_docid() const
 104 {
 105     LOGCALL(API, Xapian::docid, "ValueIterator::get_docid", NO_ARGS);
 106     Assert(internal);
 107     RETURN(internal->get_docid());
 108 }
 109
 110 Xapian::valueno
 111 ValueIterator::get_valueno() const
 112 {
 113     LOGCALL(API, Xapian::valueno, "ValueIterator::get_valueno", NO_ARGS);
 114     Assert(internal);
 115     RETURN(internal->get_valueno());
 116 }
 117
 118 void
 119 ValueIterator::skip_to(Xapian::docid docid_or_slot)
 120 {
 121     LOGCALL_VOID(API, "ValueIterator::skip_to", docid_or_slot);
 122     if (internal) {
 123         internal->skip_to(docid_or_slot);
 124         if (internal->at_end()) {
 125             decref();
 126             internal = NULL;
 127         }
 128     }
 129 }
 130
 131 bool
 132 ValueIterator::check(Xapian::docid did)
 133 {
 134     LOGCALL(API, bool, "ValueIterator::check", did);
 135     if (internal) {
 136         if (!internal->check(did)) RETURN(false);
 137         if (internal->at_end()) {
 138             decref();
 139             internal = NULL;
 140         }
 141     }
 142     RETURN(true);
 143 }
 144
 145 std::string
 146 ValueIterator::get_description() const
 147 {
 148     string desc = "ValueIterator(";
 149     if (internal)
 150         desc += internal->get_description();
 151     desc += ')';
 152     return desc;
 153 }
 154
 155 }