in_memory_url_index.h | Explore in Territory

// Copyright 2012 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef COMPONENTS_OMNIBOX_BROWSER_IN_MEMORY_URL_INDEX_H_
#define COMPONENTS_OMNIBOX_BROWSER_IN_MEMORY_URL_INDEX_H_

#include <stddef.h>

#include <functional>
#include <map>
#include <set>
#include <string>

#include "base/files/file_path.h"
#include "base/gtest_prod_util.h"
#include "base/memory/raw_ptr.h"
#include "base/memory/ref_counted.h"
#include "base/scoped_observation.h"
#include "base/task/cancelable_task_tracker.h"
#include "base/threading/thread_checker.h"
#include "base/trace_event/memory_dump_provider.h"
#include "components/history/core/browser/history_db_task.h"
#include "components/history/core/browser/history_service.h"
#include "components/history/core/browser/history_service_observer.h"
#include "components/history/core/browser/history_types.h"
#include "components/keyed_service/core/keyed_service.h"
#include "components/omnibox/browser/scored_history_match.h"
#include "components/search_engines/template_url_service.h"

class FakeAutocompleteProviderClient;
class HistoryQuickProviderTest;
class OmniboxTriggeredFeatureService;

namespace base {
class SequencedTaskRunner;
}

namespace bookmarks {
class BookmarkModel;
}

namespace history {
class HistoryDatabase;
class HQPPerfTestOnePopularURL;
}  // namespace history

class URLIndexPrivateData;

SchemeSet;

// The URL history source.
// Holds portions of the URL database in memory in an indexed form.  Used to
// quickly look up matching URLs for a given query string.  Used by
// the HistoryQuickProvider for inline autocomplete and to provide URL
// matches to the omnibox.
//
// Note about multi-byte codepoints and the data structures in the
// InMemoryURLIndex class: One will quickly notice that no effort is made to
// insure that multi-byte character boundaries are detected when indexing the
// words and characters in the URL history database except when converting
// URL strings to lowercase. Multi-byte-edness makes no difference when
// indexing or when searching the index as the final filtering of results
// is dependent on the comparison of a string of bytes, not individual
// characters. While the lookup of those bytes during a search in the
// |char_word_map_| could serve up words in which the individual char16
// occurs as a portion of a composite character the next filtering step
// will eliminate such words except in the case where a single character
// is being searched on and which character occurs as the second char16 of a
// multi-char16 instance.
class InMemoryURLIndex : public KeyedService,
                         public history::HistoryServiceObserver,
                         public base::trace_event::MemoryDumpProvider { … };

#endif  // COMPONENTS_OMNIBOX_BROWSER_IN_MEMORY_URL_INDEX_H_
chromium/components/omnibox/browser/in_memory_url_index.h
