xapian-core/api/valueiterator.cc

   1 /** @file
   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     Assert(internal);
  45     ++internal->_refs;
  46     try {
  47         internal->next();
  48     } catch (...) {
  49         // The destructor only runs if the constructor completes, so we have to
  50         // take care of cleaning up for ourselves here.
  51         decref();
  52         throw;
  53     }
  54     if (internal->at_end()) {
  55         decref();
  56         internal = NULL;
  57     }
  58 }
  59
  60 ValueIterator::ValueIterator(const ValueIterator & o)
  61     : internal(o.internal)
  62 {
  63     LOGCALL_CTOR(API, "ValueIterator", o);
  64     if (internal)
  65         ++internal->_refs;
  66 }
  67
  68 ValueIterator &
  69 ValueIterator::operator=(const ValueIterator & o)
  70 {
  71     LOGCALL(API, ValueIterator &, "ValueIterator::operator=", o);
  72     if (o.internal)
  73         ++o.internal->_refs;
  74     if (internal)
  75         decref();
  76     internal = o.internal;
  77     RETURN(*this);
  78 }
  79
  80 string
  81 ValueIterator::operator*() const
  82 {
  83     LOGCALL(API, string, "ValueIterator::operator*", NO_ARGS);
  84     Assert(internal);
  85     RETURN(internal->get_value());
  86 }
  87
  88 ValueIterator &
  89 ValueIterator::operator++()
  90 {
  91     LOGCALL(API, ValueIterator &, "ValueIterator::operator++", NO_ARGS);
  92     Assert(internal);
  93     internal->next();
  94     if (internal->at_end()) {
  95         decref();
  96         internal = NULL;
  97     }
  98     RETURN(*this);
  99 }
 100
 101 Xapian::docid
 102 ValueIterator::get_docid() const
 103 {
 104     LOGCALL(API, Xapian::docid, "ValueIterator::get_docid", NO_ARGS);
 105     Assert(internal);
 106     RETURN(internal->get_docid());
 107 }
 108
 109 Xapian::valueno
 110 ValueIterator::get_valueno() const
 111 {
 112     LOGCALL(API, Xapian::valueno, "ValueIterator::get_valueno", NO_ARGS);
 113     Assert(internal);
 114     RETURN(internal->get_valueno());
 115 }
 116
 117 void
 118 ValueIterator::skip_to(Xapian::docid docid_or_slot)
 119 {
 120     LOGCALL_VOID(API, "ValueIterator::skip_to", docid_or_slot);
 121     if (internal) {
 122         internal->skip_to(docid_or_slot);
 123         if (internal->at_end()) {
 124             decref();
 125             internal = NULL;
 126         }
 127     }
 128 }
 129
 130 bool
 131 ValueIterator::check(Xapian::docid did)
 132 {
 133     LOGCALL(API, bool, "ValueIterator::check", did);
 134     if (internal) {
 135         if (!internal->check(did)) RETURN(false);
 136         if (internal->at_end()) {
 137             decref();
 138             internal = NULL;
 139         }
 140     }
 141     RETURN(true);
 142 }
 143
 144 std::string
 145 ValueIterator::get_description() const
 146 {
 147     string desc = "ValueIterator(";
 148     if (internal)
 149         desc += internal->get_description();
 150     desc += ')';
 151     return desc;
 152 }
 153
 154 }