Support for different weight-functions for time-slicing.

chrome/browser/history/visit_database.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/history/visit_database.h"
 
 #include <algorithm>
 #include <limits>
 #include <map>
 #include <set>
@@ skipping 283 matching lines @@
   statement.BindInt(3, transition);
   statement.BindInt64(4,
       max_results ? max_results : std::numeric_limits<int64>::max());
 
   return FillVisitVector(statement, visits);
 }
 
 void VisitDatabase::GetVisibleVisitsInRange(base::Time begin_time,
                                             base::Time end_time,
                                             int max_count,
-                                            VisitVector* visits) {
+                                            VisitVector* visits,
+                                            bool unique) {
   visits->clear();
   // The visit_time values can be duplicated in a redirect chain, so we sort
   // by id too, to ensure a consistent ordering just in case.
   sql::Statement statement(GetDB().GetCachedStatement(SQL_FROM_HERE,
       "SELECT" HISTORY_VISIT_ROW_FIELDS "FROM visits "
       "WHERE visit_time >= ? AND visit_time < ? "
       "AND (transition & ?) != 0 "  // CHAIN_END
       "AND (transition & ?) NOT IN (?, ?, ?) "  // NO SUBFRAME or
                                                 // KEYWORD_GENERATED
       "ORDER BY visit_time DESC, id DESC"));
 
   // Note that we use min/max values for querying unlimited ranges of time using
   // the same statement. Since the time has an index, this will be about the
   // same amount of work as just doing a query for everything with no qualifier.
   int64 end = end_time.ToInternalValue();
   statement.BindInt64(0, begin_time.ToInternalValue());
   statement.BindInt64(1, end ? end : std::numeric_limits<int64>::max());
   statement.BindInt(2, content::PAGE_TRANSITION_CHAIN_END);
   statement.BindInt(3, content::PAGE_TRANSITION_CORE_MASK);
   statement.BindInt(4, content::PAGE_TRANSITION_AUTO_SUBFRAME);
   statement.BindInt(5, content::PAGE_TRANSITION_MANUAL_SUBFRAME);
   statement.BindInt(6, content::PAGE_TRANSITION_KEYWORD_GENERATED);
 
   std::set<URLID> found_urls;
   while (statement.Step()) {
     VisitRow visit;
     FillVisitRow(statement, &visit);
-    // Make sure the URL this visit corresponds to is unique.
-    if (found_urls.find(visit.url_id) != found_urls.end())
-      continue;
-    found_urls.insert(visit.url_id);
+    if (unique) {
+      // Make sure the URL this visit corresponds to is unique.
+      if (found_urls.find(visit.url_id) != found_urls.end())
+        continue;
+      found_urls.insert(visit.url_id);
+    }
     visits->push_back(visit);
 
     if (max_count > 0 && static_cast<int>(visits->size()) >= max_count)
       break;
   }
 }
 
 void VisitDatabase::GetVisibleVisitsDuringTimes(const VisitFilter& time_filter,
                                                 int max_results,
                                                 VisitVector* visits) {
   visits->clear();
   if (max_results)
     visits->reserve(max_results);
   for (VisitFilter::TimeVector::const_iterator it = time_filter.times().begin();
        it != time_filter.times().end(); ++it) {
     VisitVector v;
-    GetVisibleVisitsInRange(it->first, it->second, max_results, &v);
+    GetVisibleVisitsInRange(it->first, it->second, max_results, &v, false);
     size_t take_only = 0;
     if (max_results &&
         static_cast<int>(visits->size() + v.size()) > max_results) {
       take_only = max_results - visits->size();
     }
 
     visits->insert(visits->end(),
                    v.begin(), take_only ? v.begin() + take_only : v.end());
     if (max_results && static_cast<int>(visits->size()) == max_results)
       return;
@@ skipping 212 matching lines @@
   while (statement.Step()) {
     BriefVisitInfo info;
     info.url_id = statement.ColumnInt64(0);
     info.time = base::Time::FromInternalValue(statement.ColumnInt64(1));
     info.transition = content::PageTransitionFromInt(statement.ColumnInt(2));
     result_vector->push_back(info);
   }
 }
 
 }  // namespace history