backends/flint/flint_alldocspostlist.cc

Go to the documentation of this file.
00001 
00004 /* Copyright (C) 2006,2007 Olly Betts
00005  *
00006  * This program is free software; you can redistribute it and/or modify
00007  * it under the terms of the GNU General Public License as published by
00008  * the Free Software Foundation; either version 2 of the License, or
00009  * (at your option) any later version.
00010  *
00011  * This program is distributed in the hope that it will be useful,
00012  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00013  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
00014  * GNU General Public License for more details.
00015  *
00016  * You should have received a copy of the GNU General Public License
00017  * along with this program; if not, write to the Free Software
00018  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
00019  */
00020 
00021 #include <config.h>
00022 
00023 #include <string>
00024 
00025 #include "flint_database.h"
00026 #include "flint_alldocspostlist.h"
00027 
00028 #include "utils.h"
00029 
00030 using namespace std;
00031 
00032 FlintAllDocsPostList::~FlintAllDocsPostList()
00033 {
00034 }
00035 
00036 Xapian::doccount
00037 FlintAllDocsPostList::get_termfreq() const
00038 {
00039     return doccount;
00040 }
00041 
00042 Xapian::docid
00043 FlintAllDocsPostList::get_docid() const
00044 {
00045     return current_did;
00046 }
00047 
00048 Xapian::doclength
00049 FlintAllDocsPostList::get_doclength() const
00050 {
00051     DEBUGCALL(DB, Xapian::doclength, "FlintAllDocsPostList::get_doclength", "");
00052     Assert(current_did);
00053 
00054     cursor->read_tag();
00055 
00056     if (cursor->current_tag.empty()) RETURN(0);
00057 
00058     const char * pos = cursor->current_tag.data();
00059     const char * end = pos + cursor->current_tag.size();
00060 
00061     flint_doclen_t doclen;
00062     if (!unpack_uint(&pos, end, &doclen)) {
00063         const char *msg;
00064         if (pos == 0) {
00065             msg = "Too little data for doclen in termlist";
00066         } else {
00067             msg = "Overflowed value for doclen in termlist";
00068         }
00069         throw Xapian::DatabaseCorruptError(msg);
00070     }
00071 
00072     RETURN(doclen);
00073 }
00074 
00075 Xapian::termcount
00076 FlintAllDocsPostList::get_wdf() const
00077 {
00078     DEBUGCALL(DB, Xapian::termcount, "FlintAllDocsPostList::get_wdf", "");
00079     Assert(current_did);
00080     RETURN(1);
00081 }
00082 
00083 PostList *
00084 FlintAllDocsPostList::read_did_from_current_key()
00085 {
00086     DEBUGCALL(DB, PostList *, "FlintAllDocsPostList::read_did_from_current_key",
00087               "");
00088     const string & key = cursor->current_key;
00089     const char * pos = key.data();
00090     const char * end = pos + key.size();
00091     if (!unpack_uint_preserving_sort(&pos, end, &current_did)) {
00092         const char *msg;
00093         if (pos == 0) {
00094             msg = "Too little data in termlist key";
00095         } else {
00096             msg = "Overflowed value in termlist key";
00097         }
00098         throw Xapian::DatabaseCorruptError(msg);
00099     }
00100 
00101     // Return NULL to help the compiler tail-call optimise our callers.
00102     RETURN(NULL);
00103 }
00104 
00105 PostList *
00106 FlintAllDocsPostList::next(Xapian::weight /*w_min*/)
00107 {
00108     DEBUGCALL(DB, PostList *, "FlintAllDocsPostList::next", "/*w_min*/");
00109     Assert(!at_end());
00110     if (!cursor->next()) RETURN(NULL);
00111     RETURN(read_did_from_current_key());
00112 }
00113 
00114 PostList *
00115 FlintAllDocsPostList::skip_to(Xapian::docid did, Xapian::weight /*w_min*/)
00116 {
00117     DEBUGCALL(DB, PostList *, "FlintAllDocsPostList::skip_to",
00118               did << ", /*w_min*/");
00119 
00120     if (did <= current_did || at_end()) RETURN(NULL);
00121 
00122     if (cursor->find_entry_ge(pack_uint_preserving_sort(did))) {
00123         // The exact docid that was asked for exists.
00124         current_did = did;
00125         RETURN(NULL);
00126     }
00127     if (cursor->after_end()) RETURN(NULL);
00128 
00129     RETURN(read_did_from_current_key());
00130 }
00131 
00132 bool
00133 FlintAllDocsPostList::at_end() const {
00134     DEBUGCALL(DB, bool, "FlintAllDocsPostList::at_end", "");
00135     RETURN(cursor->after_end());
00136 }
00137 
00138 string
00139 FlintAllDocsPostList::get_description() const
00140 {
00141     string desc = "FlintAllDocsPostList(did=";
00142     desc += om_tostring(current_did);
00143     desc += ",doccount=";
00144     desc += om_tostring(doccount);
00145     desc += ')';
00146     return desc;
00147 }

Documentation for Xapian (version 1.0.10).
Generated on 24 Dec 2008 by Doxygen 1.5.2.