Replace FTS in the history_service with a brute force text search.

chrome/browser/history/history_backend.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/history_backend.h"
 
 #include <algorithm>
 #include <functional>
 #include <list>
 #include <map>
@@ skipping 1340 matching lines @@
       QueryHistoryBasic(db_.get(), db_.get(), options, &request->value);
 
       // Now query the archived database. This is a bit tricky because we don't
       // want to query it if the queried time range isn't going to find anything
       // in it.
       // TODO(brettw) bug 1171036: do blimpie querying for the archived database
       // as well.
       // if (archived_db_.get() &&
       //     expirer_.GetCurrentArchiveTime() - TimeDelta::FromDays(7)) {
     } else {
-      // Full text history query.
-      QueryHistoryFTS(text_query, options, &request->value);
+      // Text history query.
+      QueryHistoryText(db_.get(), db_.get(), text_query, options,
+                       &request->value);
+      if (archived_db_.get() &&
+          expirer_.GetCurrentArchiveTime() >= options.begin_time) {
+        QueryHistoryText(archived_db_.get(), archived_db_.get(), text_query,
+                         options, &request->value);
+      }
     }
   }
 
   request->ForwardResult(request->handle(), &request->value);
 
   UMA_HISTOGRAM_TIMES("History.QueryHistory",
                       TimeTicks::Now() - beginning_time);
 }
 
 // Basic time-based querying of history.
@@ skipping 44 matching lines @@
 
     // We don't set any of the query-specific parts of the URLResult, since
     // snippets and stuff don't apply to basic querying.
     result->AppendURLBySwapping(&url_result);
   }
 
   if (!has_more_results && options.begin_time <= first_recorded_time_)
     result->set_reached_beginning(true);
 }
 
+// Text-based querying of history.
+void HistoryBackend::QueryHistoryText(URLDatabase* url_db,
+                                      VisitDatabase* visit_db,
+                                      const string16& text_query,
+                                      const QueryOptions& options,
+                                      QueryResults* result) {

[Scott Hess - ex-Googler, 2013/06/20 19:50:22]

Do you think there would be any value to histogramming timing information for
this function?  Not breaking it down, but just getting the overall cost.

[rmcilroy, 2013/06/20 21:48:08]

There is already a timing histogram for the caller of this function (line 1374)
which measures timings of both basic and text searches ("History.QueryHistory").
 I think this is sufficient, what do you think?

[Scott Hess - ex-Googler, 2013/06/20 22:18:31]

Sounds good.

+  URLRows text_matches;
+  url_db->GetTextMatches(text_query, &text_matches);
+
+  std::vector<URLResult> matching_visits;
+  VisitVector visits;    // Declare outside loop to prevent re-construction.
+  for (size_t i = 0; i < text_matches.size(); i++) {
+    const URLRow& text_match = text_matches[i];
+    // Get all visits for given URL match.
+    visit_db->GetVisitsForURLWithOptions(text_match.id(), options, &visits);
+    for (size_t j = 0; j < visits.size(); j++) {
+      URLResult url_result(text_match);
+      url_result.set_visit_time(visits[j].visit_time);
+      matching_visits.push_back(url_result);
+    }
+  }
+
+  std::sort(matching_visits.begin(), matching_visits.end(),
+            URLResult::CompareVisitTime);
+
+  size_t max_results = options.max_count == 0 ?
+      std::numeric_limits<size_t>::max() : static_cast<int>(options.max_count);
+  for (std::vector<URLResult>::iterator it = matching_visits.begin();
+       it != matching_visits.end() && result->size() < max_results; ++it) {
+    result->AppendURLBySwapping(&(*it));
+  }
+
+  if (matching_visits.size() == result->size() &&
+      options.begin_time <= first_recorded_time_)
+    result->set_reached_beginning(true);
+}
+
 void HistoryBackend::QueryHistoryFTS(const string16& text_query,
                                      const QueryOptions& options,
                                      QueryResults* result) {
   if (!text_database_)
     return;
 
   // Full text query, first get all the FTS results in the time range.
   std::vector<TextDatabase::Match> fts_matches;
   Time first_time_searched;
   text_database_->GetTextMatches(text_query, options,
@@ skipping 1631 matching lines @@
   info.url_id = visit.url_id;
   info.time = visit.visit_time;
   info.transition = visit.transition;
   // If we don't have a delegate yet during setup or shutdown, we will drop
   // these notifications.
   if (delegate_)
     delegate_->NotifyVisitDBObserversOnAddVisit(info);
 }
 
 }  // namespace history