history_service.cc revision 58537e28ecd584eab876aee8be7156509866d23a 
1// Copyright (c) 2012 The Chromium Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5// The history system runs on a background thread so that potentially slow
6// database operations don't delay the browser. This backend processing is
7// represented by HistoryBackend. The HistoryService's job is to dispatch to
8// that thread.
9//
10// Main thread                       History thread
11// -----------                       --------------
12// HistoryService <----------------> HistoryBackend
13//                                   -> HistoryDatabase
14//                                      -> SQLite connection to History
15//                                   -> ArchivedDatabase
16//                                      -> SQLite connection to Archived History
17//                                   -> ThumbnailDatabase
18//                                      -> SQLite connection to Thumbnails
19//                                         (and favicons)
20
21#include "chrome/browser/history/history_service.h"
22
23#include "base/bind_helpers.h"
24#include "base/callback.h"
25#include "base/command_line.h"
26#include "base/compiler_specific.h"
27#include "base/location.h"
28#include "base/memory/ref_counted.h"
29#include "base/message_loop/message_loop.h"
30#include "base/path_service.h"
31#include "base/prefs/pref_service.h"
32#include "base/thread_task_runner_handle.h"
33#include "base/threading/thread.h"
34#include "base/time/time.h"
35#include "chrome/browser/autocomplete/history_url_provider.h"
36#include "chrome/browser/bookmarks/bookmark_model.h"
37#include "chrome/browser/bookmarks/bookmark_model_factory.h"
38#include "chrome/browser/browser_process.h"
39#include "chrome/browser/chrome_notification_types.h"
40#include "chrome/browser/history/download_row.h"
41#include "chrome/browser/history/history_backend.h"
42#include "chrome/browser/history/history_notifications.h"
43#include "chrome/browser/history/history_types.h"
44#include "chrome/browser/history/in_memory_database.h"
45#include "chrome/browser/history/in_memory_history_backend.h"
46#include "chrome/browser/history/in_memory_url_index.h"
47#include "chrome/browser/history/top_sites.h"
48#include "chrome/browser/history/visit_database.h"
49#include "chrome/browser/history/visit_filter.h"
50#include "chrome/browser/history/web_history_service.h"
51#include "chrome/browser/history/web_history_service_factory.h"
52#include "chrome/browser/profiles/profile.h"
53#include "chrome/browser/ui/profile_error_dialog.h"
54#include "chrome/common/chrome_constants.h"
55#include "chrome/common/chrome_switches.h"
56#include "chrome/common/importer/imported_favicon_usage.h"
57#include "chrome/common/pref_names.h"
58#include "chrome/common/thumbnail_score.h"
59#include "chrome/common/url_constants.h"
60#include "components/visitedlink/browser/visitedlink_master.h"
61#include "content/public/browser/browser_thread.h"
62#include "content/public/browser/download_item.h"
63#include "content/public/browser/notification_service.h"
64#include "grit/chromium_strings.h"
65#include "grit/generated_resources.h"
66#include "sync/api/sync_error_factory.h"
67#include "third_party/skia/include/core/SkBitmap.h"
68
69using base::Time;
70using history::HistoryBackend;
71
72namespace {
73
74static const char* kHistoryThreadName = "Chrome_HistoryThread";
75
76template<typename PODType> void DerefPODType(
77    const base::Callback<void(PODType)>& callback, PODType* pod_value) {
78  callback.Run(*pod_value);
79}
80
81void RunWithFaviconResults(
82    const FaviconService::FaviconResultsCallback& callback,
83    std::vector<chrome::FaviconBitmapResult>* bitmap_results) {
84  callback.Run(*bitmap_results);
85}
86
87// Extract history::URLRows into GURLs for VisitedLinkMaster.
88class URLIteratorFromURLRows
89    : public visitedlink::VisitedLinkMaster::URLIterator {
90 public:
91  explicit URLIteratorFromURLRows(const history::URLRows& url_rows)
92      : itr_(url_rows.begin()),
93        end_(url_rows.end()) {
94  }
95
96  virtual const GURL& NextURL() OVERRIDE {
97    return (itr_++)->url();
98  }
99
100  virtual bool HasNextURL() const OVERRIDE {
101    return itr_ != end_;
102  }
103
104 private:
105  history::URLRows::const_iterator itr_;
106  history::URLRows::const_iterator end_;
107
108  DISALLOW_COPY_AND_ASSIGN(URLIteratorFromURLRows);
109};
110
111// Callback from WebHistoryService::ExpireWebHistory().
112void ExpireWebHistoryComplete(
113    history::WebHistoryService::Request* request,
114    bool success) {
115  // Ignore the result and delete the request.
116  delete request;
117}
118
119}  // namespace
120
121// Sends messages from the backend to us on the main thread. This must be a
122// separate class from the history service so that it can hold a reference to
123// the history service (otherwise we would have to manually AddRef and
124// Release when the Backend has a reference to us).
125class HistoryService::BackendDelegate : public HistoryBackend::Delegate {
126 public:
127  BackendDelegate(
128      const base::WeakPtr<HistoryService>& history_service,
129      const scoped_refptr<base::SequencedTaskRunner>& service_task_runner,
130      Profile* profile)
131      : history_service_(history_service),
132        service_task_runner_(service_task_runner),
133        profile_(profile) {
134  }
135
136  virtual void NotifyProfileError(int backend_id,
137                                  sql::InitStatus init_status) OVERRIDE {
138    // Send to the history service on the main thread.
139    service_task_runner_->PostTask(
140        FROM_HERE,
141        base::Bind(&HistoryService::NotifyProfileError, history_service_,
142                   backend_id, init_status));
143  }
144
145  virtual void SetInMemoryBackend(int backend_id,
146      history::InMemoryHistoryBackend* backend) OVERRIDE {
147    // Send the backend to the history service on the main thread.
148    scoped_ptr<history::InMemoryHistoryBackend> in_memory_backend(backend);
149    service_task_runner_->PostTask(
150        FROM_HERE,
151        base::Bind(&HistoryService::SetInMemoryBackend, history_service_,
152                   backend_id, base::Passed(&in_memory_backend)));
153  }
154
155  virtual void BroadcastNotifications(
156      int type,
157      history::HistoryDetails* details) OVERRIDE {
158    // Send the notification on the history thread.
159    if (content::NotificationService::current()) {
160      content::Details<history::HistoryDetails> det(details);
161      content::NotificationService::current()->Notify(
162          type, content::Source<Profile>(profile_), det);
163    }
164    // Send the notification to the history service on the main thread.
165    service_task_runner_->PostTask(
166        FROM_HERE,
167        base::Bind(&HistoryService::BroadcastNotificationsHelper,
168                   history_service_, type, base::Owned(details)));
169  }
170
171  virtual void DBLoaded(int backend_id) OVERRIDE {
172    service_task_runner_->PostTask(
173        FROM_HERE,
174        base::Bind(&HistoryService::OnDBLoaded, history_service_,
175                   backend_id));
176  }
177
178  virtual void NotifyVisitDBObserversOnAddVisit(
179      const history::BriefVisitInfo& info) OVERRIDE {
180    service_task_runner_->PostTask(
181        FROM_HERE,
182        base::Bind(&HistoryService::NotifyVisitDBObserversOnAddVisit,
183                   history_service_, info));
184  }
185
186 private:
187  const base::WeakPtr<HistoryService> history_service_;
188  const scoped_refptr<base::SequencedTaskRunner> service_task_runner_;
189  Profile* const profile_;
190};
191
192// The history thread is intentionally not a BrowserThread because the
193// sync integration unit tests depend on being able to create more than one
194// history thread.
195HistoryService::HistoryService()
196    : weak_ptr_factory_(this),
197      thread_(new base::Thread(kHistoryThreadName)),
198      profile_(NULL),
199      backend_loaded_(false),
200      current_backend_id_(-1),
201      bookmark_service_(NULL),
202      no_db_(false) {
203}
204
205HistoryService::HistoryService(Profile* profile)
206    : weak_ptr_factory_(this),
207      thread_(new base::Thread(kHistoryThreadName)),
208      profile_(profile),
209      visitedlink_master_(new visitedlink::VisitedLinkMaster(
210          profile, this, true)),
211      backend_loaded_(false),
212      current_backend_id_(-1),
213      bookmark_service_(NULL),
214      no_db_(false) {
215  DCHECK(profile_);
216  registrar_.Add(this, chrome::NOTIFICATION_HISTORY_URLS_DELETED,
217                 content::Source<Profile>(profile_));
218  registrar_.Add(this, chrome::NOTIFICATION_TEMPLATE_URL_REMOVED,
219                 content::Source<Profile>(profile_));
220}
221
222HistoryService::~HistoryService() {
223  DCHECK(thread_checker_.CalledOnValidThread());
224  // Shutdown the backend. This does nothing if Cleanup was already invoked.
225  Cleanup();
226}
227
228bool HistoryService::BackendLoaded() {
229  DCHECK(thread_checker_.CalledOnValidThread());
230  // NOTE: We start the backend loading even though it completes asynchronously
231  // and thus won't affect the return value of this function.  This is because
232  // callers of this assume that if the backend isn't yet loaded it will be
233  // soon, so they will either listen for notifications or just retry this call
234  // later.  If we've purged the backend, we haven't necessarily restarted it
235  // loading by now, so we need to trigger the load in order to maintain that
236  // expectation.
237  LoadBackendIfNecessary();
238  return backend_loaded_;
239}
240
241void HistoryService::UnloadBackend() {
242  DCHECK(thread_checker_.CalledOnValidThread());
243  if (!history_backend_.get())
244    return;  // Already unloaded.
245
246  // Get rid of the in-memory backend.
247  in_memory_backend_.reset();
248
249  // Give the InMemoryURLIndex a chance to shutdown.
250  if (in_memory_url_index_)
251    in_memory_url_index_->ShutDown();
252
253  // The backend's destructor must run on the history thread since it is not
254  // threadsafe. So this thread must not be the last thread holding a reference
255  // to the backend, or a crash could happen.
256  //
257  // We have a reference to the history backend. There is also an extra
258  // reference held by our delegate installed in the backend, which
259  // HistoryBackend::Closing will release. This means if we scheduled a call
260  // to HistoryBackend::Closing and *then* released our backend reference, there
261  // will be a race between us and the backend's Closing function to see who is
262  // the last holder of a reference. If the backend thread's Closing manages to
263  // run before we release our backend refptr, the last reference will be held
264  // by this thread and the destructor will be called from here.
265  //
266  // Therefore, we create a closure to run the Closing operation first. This
267  // holds a reference to the backend. Then we release our reference, then we
268  // schedule the task to run. After the task runs, it will delete its reference
269  // from the history thread, ensuring everything works properly.
270  //
271  // TODO(ajwong): Cleanup HistoryBackend lifetime issues.
272  //     See http://crbug.com/99767.
273  history_backend_->AddRef();
274  base::Closure closing_task =
275      base::Bind(&HistoryBackend::Closing, history_backend_.get());
276  ScheduleTask(PRIORITY_NORMAL, closing_task);
277  closing_task.Reset();
278  HistoryBackend* raw_ptr = history_backend_.get();
279  history_backend_ = NULL;
280  thread_->message_loop()->ReleaseSoon(FROM_HERE, raw_ptr);
281}
282
283void HistoryService::Cleanup() {
284  DCHECK(thread_checker_.CalledOnValidThread());
285  if (!thread_) {
286    // We've already cleaned up.
287    return;
288  }
289
290  weak_ptr_factory_.InvalidateWeakPtrs();
291
292  // Unload the backend.
293  UnloadBackend();
294
295  // Delete the thread, which joins with the background thread. We defensively
296  // NULL the pointer before deleting it in case somebody tries to use it
297  // during shutdown, but this shouldn't happen.
298  base::Thread* thread = thread_;
299  thread_ = NULL;
300  delete thread;
301}
302
303void HistoryService::NotifyRenderProcessHostDestruction(const void* host) {
304  DCHECK(thread_checker_.CalledOnValidThread());
305  ScheduleAndForget(PRIORITY_NORMAL,
306                    &HistoryBackend::NotifyRenderProcessHostDestruction, host);
307}
308
309history::URLDatabase* HistoryService::InMemoryDatabase() {
310  DCHECK(thread_checker_.CalledOnValidThread());
311  // NOTE: See comments in BackendLoaded() as to why we call
312  // LoadBackendIfNecessary() here even though it won't affect the return value
313  // for this call.
314  LoadBackendIfNecessary();
315  if (in_memory_backend_)
316    return in_memory_backend_->db();
317  return NULL;
318}
319
320bool HistoryService::GetTypedCountForURL(const GURL& url, int* typed_count) {
321  DCHECK(thread_checker_.CalledOnValidThread());
322  history::URLRow url_row;
323  if (!GetRowForURL(url, &url_row))
324    return false;
325  *typed_count = url_row.typed_count();
326  return true;
327}
328
329bool HistoryService::GetLastVisitTimeForURL(const GURL& url,
330                                            base::Time* last_visit) {
331  DCHECK(thread_checker_.CalledOnValidThread());
332  history::URLRow url_row;
333  if (!GetRowForURL(url, &url_row))
334    return false;
335  *last_visit = url_row.last_visit();
336  return true;
337}
338
339bool HistoryService::GetVisitCountForURL(const GURL& url, int* visit_count) {
340  DCHECK(thread_checker_.CalledOnValidThread());
341  history::URLRow url_row;
342  if (!GetRowForURL(url, &url_row))
343    return false;
344  *visit_count = url_row.visit_count();
345  return true;
346}
347
348history::TypedUrlSyncableService* HistoryService::GetTypedUrlSyncableService()
349    const {
350  return history_backend_->GetTypedUrlSyncableService();
351}
352
353void HistoryService::Shutdown() {
354  DCHECK(thread_checker_.CalledOnValidThread());
355  // It's possible that bookmarks haven't loaded and history is waiting for
356  // bookmarks to complete loading. In such a situation history can't shutdown
357  // (meaning if we invoked history_service_->Cleanup now, we would
358  // deadlock). To break the deadlock we tell BookmarkModel it's about to be
359  // deleted so that it can release the signal history is waiting on, allowing
360  // history to shutdown (history_service_->Cleanup to complete). In such a
361  // scenario history sees an incorrect view of bookmarks, but it's better
362  // than a deadlock.
363  BookmarkModel* bookmark_model = static_cast<BookmarkModel*>(
364      BookmarkModelFactory::GetForProfileIfExists(profile_));
365  if (bookmark_model)
366    bookmark_model->Shutdown();
367
368  Cleanup();
369}
370
371void HistoryService::SetKeywordSearchTermsForURL(const GURL& url,
372                                                 TemplateURLID keyword_id,
373                                                 const string16& term) {
374  DCHECK(thread_checker_.CalledOnValidThread());
375  ScheduleAndForget(PRIORITY_UI,
376                    &HistoryBackend::SetKeywordSearchTermsForURL,
377                    url, keyword_id, term);
378}
379
380void HistoryService::DeleteAllSearchTermsForKeyword(
381    TemplateURLID keyword_id) {
382  DCHECK(thread_checker_.CalledOnValidThread());
383  ScheduleAndForget(PRIORITY_UI,
384                    &HistoryBackend::DeleteAllSearchTermsForKeyword,
385                    keyword_id);
386}
387
388HistoryService::Handle HistoryService::GetMostRecentKeywordSearchTerms(
389    TemplateURLID keyword_id,
390    const string16& prefix,
391    int max_count,
392    CancelableRequestConsumerBase* consumer,
393    const GetMostRecentKeywordSearchTermsCallback& callback) {
394  DCHECK(thread_checker_.CalledOnValidThread());
395  return Schedule(PRIORITY_UI, &HistoryBackend::GetMostRecentKeywordSearchTerms,
396                  consumer,
397                  new history::GetMostRecentKeywordSearchTermsRequest(callback),
398                  keyword_id, prefix, max_count);
399}
400
401void HistoryService::URLsNoLongerBookmarked(const std::set<GURL>& urls) {
402  DCHECK(thread_checker_.CalledOnValidThread());
403  ScheduleAndForget(PRIORITY_NORMAL, &HistoryBackend::URLsNoLongerBookmarked,
404                    urls);
405}
406
407void HistoryService::ScheduleDBTask(history::HistoryDBTask* task,
408                                    CancelableRequestConsumerBase* consumer) {
409  DCHECK(thread_checker_.CalledOnValidThread());
410  history::HistoryDBTaskRequest* request = new history::HistoryDBTaskRequest(
411      base::Bind(&history::HistoryDBTask::DoneRunOnMainThread, task));
412  request->value = task;  // The value is the task to execute.
413  Schedule(PRIORITY_UI, &HistoryBackend::ProcessDBTask, consumer, request);
414}
415
416HistoryService::Handle HistoryService::QuerySegmentUsageSince(
417    CancelableRequestConsumerBase* consumer,
418    const Time from_time,
419    int max_result_count,
420    const SegmentQueryCallback& callback) {
421  DCHECK(thread_checker_.CalledOnValidThread());
422  return Schedule(PRIORITY_UI, &HistoryBackend::QuerySegmentUsage,
423                  consumer, new history::QuerySegmentUsageRequest(callback),
424                  from_time, max_result_count);
425}
426
427void HistoryService::IncreaseSegmentDuration(const GURL& url,
428                                             Time time,
429                                             base::TimeDelta delta) {
430  DCHECK(thread_checker_.CalledOnValidThread());
431  ScheduleAndForget(PRIORITY_NORMAL, &HistoryBackend::IncreaseSegmentDuration,
432                    url, time, delta);
433}
434
435HistoryService::Handle HistoryService::QuerySegmentDurationSince(
436    CancelableRequestConsumerBase* consumer,
437    base::Time from_time,
438    int max_result_count,
439    const SegmentQueryCallback& callback) {
440  DCHECK(thread_checker_.CalledOnValidThread());
441  return Schedule(PRIORITY_UI, &HistoryBackend::QuerySegmentDuration,
442                  consumer, new history::QuerySegmentUsageRequest(callback),
443                  from_time, max_result_count);
444}
445
446void HistoryService::FlushForTest(const base::Closure& flushed) {
447  thread_->message_loop_proxy()->PostTaskAndReply(
448      FROM_HERE, base::Bind(&base::DoNothing), flushed);
449}
450
451void HistoryService::SetOnBackendDestroyTask(const base::Closure& task) {
452  DCHECK(thread_checker_.CalledOnValidThread());
453  ScheduleAndForget(PRIORITY_NORMAL, &HistoryBackend::SetOnBackendDestroyTask,
454                    base::MessageLoop::current(), task);
455}
456
457void HistoryService::AddPage(const GURL& url,
458                             Time time,
459                             const void* id_scope,
460                             int32 page_id,
461                             const GURL& referrer,
462                             const history::RedirectList& redirects,
463                             content::PageTransition transition,
464                             history::VisitSource visit_source,
465                             bool did_replace_entry) {
466  DCHECK(thread_checker_.CalledOnValidThread());
467  AddPage(
468      history::HistoryAddPageArgs(url, time, id_scope, page_id, referrer,
469                                  redirects, transition, visit_source,
470                                  did_replace_entry));
471}
472
473void HistoryService::AddPage(const GURL& url,
474                             base::Time time,
475                             history::VisitSource visit_source) {
476  DCHECK(thread_checker_.CalledOnValidThread());
477  AddPage(
478      history::HistoryAddPageArgs(url, time, NULL, 0, GURL(),
479                                  history::RedirectList(),
480                                  content::PAGE_TRANSITION_LINK,
481                                  visit_source, false));
482}
483
484void HistoryService::AddPage(const history::HistoryAddPageArgs& add_page_args) {
485  DCHECK(thread_checker_.CalledOnValidThread());
486  DCHECK(thread_) << "History service being called after cleanup";
487
488  // Filter out unwanted URLs. We don't add auto-subframe URLs. They are a
489  // large part of history (think iframes for ads) and we never display them in
490  // history UI. We will still add manual subframes, which are ones the user
491  // has clicked on to get.
492  if (!CanAddURL(add_page_args.url))
493    return;
494
495  // Add link & all redirects to visited link list.
496  if (visitedlink_master_) {
497    visitedlink_master_->AddURL(add_page_args.url);
498
499    if (!add_page_args.redirects.empty()) {
500      // We should not be asked to add a page in the middle of a redirect chain.
501      DCHECK_EQ(add_page_args.url,
502                add_page_args.redirects[add_page_args.redirects.size() - 1]);
503
504      // We need the !redirects.empty() condition above since size_t is unsigned
505      // and will wrap around when we subtract one from a 0 size.
506      for (size_t i = 0; i < add_page_args.redirects.size() - 1; i++)
507        visitedlink_master_->AddURL(add_page_args.redirects[i]);
508    }
509  }
510
511  ScheduleAndForget(PRIORITY_NORMAL, &HistoryBackend::AddPage, add_page_args);
512}
513
514void HistoryService::AddPageNoVisitForBookmark(const GURL& url,
515                                               const string16& title) {
516  DCHECK(thread_checker_.CalledOnValidThread());
517  if (!CanAddURL(url))
518    return;
519
520  ScheduleAndForget(PRIORITY_NORMAL,
521                    &HistoryBackend::AddPageNoVisitForBookmark, url, title);
522}
523
524void HistoryService::SetPageTitle(const GURL& url,
525                                  const string16& title) {
526  DCHECK(thread_checker_.CalledOnValidThread());
527  ScheduleAndForget(PRIORITY_NORMAL, &HistoryBackend::SetPageTitle, url, title);
528}
529
530void HistoryService::UpdateWithPageEndTime(const void* host,
531                                           int32 page_id,
532                                           const GURL& url,
533                                           Time end_ts) {
534  DCHECK(thread_checker_.CalledOnValidThread());
535  ScheduleAndForget(PRIORITY_NORMAL, &HistoryBackend::UpdateWithPageEndTime,
536                    host, page_id, url, end_ts);
537}
538
539void HistoryService::AddPageWithDetails(const GURL& url,
540                                        const string16& title,
541                                        int visit_count,
542                                        int typed_count,
543                                        Time last_visit,
544                                        bool hidden,
545                                        history::VisitSource visit_source) {
546  DCHECK(thread_checker_.CalledOnValidThread());
547  // Filter out unwanted URLs.
548  if (!CanAddURL(url))
549    return;
550
551  // Add to the visited links system.
552  if (visitedlink_master_)
553    visitedlink_master_->AddURL(url);
554
555  history::URLRow row(url);
556  row.set_title(title);
557  row.set_visit_count(visit_count);
558  row.set_typed_count(typed_count);
559  row.set_last_visit(last_visit);
560  row.set_hidden(hidden);
561
562  history::URLRows rows;
563  rows.push_back(row);
564
565  ScheduleAndForget(PRIORITY_NORMAL,
566                    &HistoryBackend::AddPagesWithDetails, rows, visit_source);
567}
568
569void HistoryService::AddPagesWithDetails(const history::URLRows& info,
570                                         history::VisitSource visit_source) {
571  DCHECK(thread_checker_.CalledOnValidThread());
572  // Add to the visited links system.
573  if (visitedlink_master_) {
574    std::vector<GURL> urls;
575    urls.reserve(info.size());
576    for (history::URLRows::const_iterator i = info.begin(); i != info.end();
577         ++i)
578      urls.push_back(i->url());
579
580    visitedlink_master_->AddURLs(urls);
581  }
582
583  ScheduleAndForget(PRIORITY_NORMAL,
584                    &HistoryBackend::AddPagesWithDetails, info, visit_source);
585}
586
587CancelableTaskTracker::TaskId HistoryService::GetFavicons(
588    const std::vector<GURL>& icon_urls,
589    int icon_types,
590    int desired_size_in_dip,
591    const std::vector<ui::ScaleFactor>& desired_scale_factors,
592    const FaviconService::FaviconResultsCallback& callback,
593    CancelableTaskTracker* tracker) {
594  DCHECK(thread_checker_.CalledOnValidThread());
595  LoadBackendIfNecessary();
596
597  std::vector<chrome::FaviconBitmapResult>* results =
598      new std::vector<chrome::FaviconBitmapResult>();
599  return tracker->PostTaskAndReply(
600      thread_->message_loop_proxy().get(),
601      FROM_HERE,
602      base::Bind(&HistoryBackend::GetFavicons,
603                 history_backend_.get(),
604                 icon_urls,
605                 icon_types,
606                 desired_size_in_dip,
607                 desired_scale_factors,
608                 results),
609      base::Bind(&RunWithFaviconResults, callback, base::Owned(results)));
610}
611
612CancelableTaskTracker::TaskId HistoryService::GetFaviconsForURL(
613    const GURL& page_url,
614    int icon_types,
615    int desired_size_in_dip,
616    const std::vector<ui::ScaleFactor>& desired_scale_factors,
617    const FaviconService::FaviconResultsCallback& callback,
618    CancelableTaskTracker* tracker) {
619  DCHECK(thread_checker_.CalledOnValidThread());
620  LoadBackendIfNecessary();
621
622  std::vector<chrome::FaviconBitmapResult>* results =
623      new std::vector<chrome::FaviconBitmapResult>();
624  return tracker->PostTaskAndReply(
625      thread_->message_loop_proxy().get(),
626      FROM_HERE,
627      base::Bind(&HistoryBackend::GetFaviconsForURL,
628                 history_backend_.get(),
629                 page_url,
630                 icon_types,
631                 desired_size_in_dip,
632                 desired_scale_factors,
633                 results),
634      base::Bind(&RunWithFaviconResults, callback, base::Owned(results)));
635}
636
637CancelableTaskTracker::TaskId HistoryService::GetFaviconForID(
638    chrome::FaviconID favicon_id,
639    int desired_size_in_dip,
640    ui::ScaleFactor desired_scale_factor,
641    const FaviconService::FaviconResultsCallback& callback,
642    CancelableTaskTracker* tracker) {
643  DCHECK(thread_checker_.CalledOnValidThread());
644  LoadBackendIfNecessary();
645
646  std::vector<chrome::FaviconBitmapResult>* results =
647      new std::vector<chrome::FaviconBitmapResult>();
648  return tracker->PostTaskAndReply(
649      thread_->message_loop_proxy().get(),
650      FROM_HERE,
651      base::Bind(&HistoryBackend::GetFaviconForID,
652                 history_backend_.get(),
653                 favicon_id,
654                 desired_size_in_dip,
655                 desired_scale_factor,
656                 results),
657      base::Bind(&RunWithFaviconResults, callback, base::Owned(results)));
658}
659
660CancelableTaskTracker::TaskId HistoryService::UpdateFaviconMappingsAndFetch(
661    const GURL& page_url,
662    const std::vector<GURL>& icon_urls,
663    int icon_types,
664    int desired_size_in_dip,
665    const std::vector<ui::ScaleFactor>& desired_scale_factors,
666    const FaviconService::FaviconResultsCallback& callback,
667    CancelableTaskTracker* tracker) {
668  DCHECK(thread_checker_.CalledOnValidThread());
669  LoadBackendIfNecessary();
670
671  std::vector<chrome::FaviconBitmapResult>* results =
672      new std::vector<chrome::FaviconBitmapResult>();
673  return tracker->PostTaskAndReply(
674      thread_->message_loop_proxy().get(),
675      FROM_HERE,
676      base::Bind(&HistoryBackend::UpdateFaviconMappingsAndFetch,
677                 history_backend_.get(),
678                 page_url,
679                 icon_urls,
680                 icon_types,
681                 desired_size_in_dip,
682                 desired_scale_factors,
683                 results),
684      base::Bind(&RunWithFaviconResults, callback, base::Owned(results)));
685}
686
687void HistoryService::MergeFavicon(
688    const GURL& page_url,
689    const GURL& icon_url,
690    chrome::IconType icon_type,
691    scoped_refptr<base::RefCountedMemory> bitmap_data,
692    const gfx::Size& pixel_size) {
693  DCHECK(thread_checker_.CalledOnValidThread());
694  if (!CanAddURL(page_url))
695    return;
696
697  ScheduleAndForget(PRIORITY_NORMAL, &HistoryBackend::MergeFavicon, page_url,
698                    icon_url, icon_type, bitmap_data, pixel_size);
699}
700
701void HistoryService::SetFavicons(
702    const GURL& page_url,
703    chrome::IconType icon_type,
704    const std::vector<chrome::FaviconBitmapData>& favicon_bitmap_data) {
705  DCHECK(thread_checker_.CalledOnValidThread());
706  if (!CanAddURL(page_url))
707    return;
708
709  ScheduleAndForget(PRIORITY_NORMAL, &HistoryBackend::SetFavicons, page_url,
710      icon_type, favicon_bitmap_data);
711}
712
713void HistoryService::SetFaviconsOutOfDateForPage(const GURL& page_url) {
714  DCHECK(thread_checker_.CalledOnValidThread());
715  ScheduleAndForget(PRIORITY_NORMAL,
716                    &HistoryBackend::SetFaviconsOutOfDateForPage, page_url);
717}
718
719void HistoryService::CloneFavicons(const GURL& old_page_url,
720                                   const GURL& new_page_url) {
721  DCHECK(thread_checker_.CalledOnValidThread());
722  ScheduleAndForget(PRIORITY_NORMAL, &HistoryBackend::CloneFavicons,
723                    old_page_url, new_page_url);
724}
725
726void HistoryService::SetImportedFavicons(
727    const std::vector<ImportedFaviconUsage>& favicon_usage) {
728  DCHECK(thread_checker_.CalledOnValidThread());
729  ScheduleAndForget(PRIORITY_NORMAL,
730                    &HistoryBackend::SetImportedFavicons, favicon_usage);
731}
732
733HistoryService::Handle HistoryService::QueryURL(
734    const GURL& url,
735    bool want_visits,
736    CancelableRequestConsumerBase* consumer,
737    const QueryURLCallback& callback) {
738  DCHECK(thread_checker_.CalledOnValidThread());
739  return Schedule(PRIORITY_UI, &HistoryBackend::QueryURL, consumer,
740                  new history::QueryURLRequest(callback), url, want_visits);
741}
742
743// Downloads -------------------------------------------------------------------
744
745// Handle creation of a download by creating an entry in the history service's
746// 'downloads' table.
747void HistoryService::CreateDownload(
748    const history::DownloadRow& create_info,
749    const HistoryService::DownloadCreateCallback& callback) {
750  DCHECK(thread_) << "History service being called after cleanup";
751  DCHECK(thread_checker_.CalledOnValidThread());
752  LoadBackendIfNecessary();
753  bool* success = new bool(false);
754  thread_->message_loop_proxy()->PostTaskAndReply(
755      FROM_HERE,
756      base::Bind(&HistoryBackend::CreateDownload,
757                 history_backend_.get(),
758                 create_info,
759                 success),
760      base::Bind(&DerefPODType<bool>, callback, base::Owned(success)));
761}
762
763void HistoryService::GetNextDownloadId(
764    const content::DownloadIdCallback& callback) {
765  DCHECK(thread_) << "History service being called after cleanup";
766  DCHECK(thread_checker_.CalledOnValidThread());
767  LoadBackendIfNecessary();
768  uint32* next_id = new uint32(content::DownloadItem::kInvalidId);
769  thread_->message_loop_proxy()->PostTaskAndReply(
770      FROM_HERE,
771      base::Bind(&HistoryBackend::GetNextDownloadId,
772                 history_backend_.get(),
773                 next_id),
774      base::Bind(&DerefPODType<uint32>, callback, base::Owned(next_id)));
775}
776
777// Handle queries for a list of all downloads in the history database's
778// 'downloads' table.
779void HistoryService::QueryDownloads(
780    const DownloadQueryCallback& callback) {
781  DCHECK(thread_) << "History service being called after cleanup";
782  DCHECK(thread_checker_.CalledOnValidThread());
783  LoadBackendIfNecessary();
784  std::vector<history::DownloadRow>* rows =
785    new std::vector<history::DownloadRow>();
786  scoped_ptr<std::vector<history::DownloadRow> > scoped_rows(rows);
787  // Beware! The first Bind() does not simply |scoped_rows.get()| because
788  // base::Passed(&scoped_rows) nullifies |scoped_rows|, and compilers do not
789  // guarantee that the first Bind's arguments are evaluated before the second
790  // Bind's arguments.
791  thread_->message_loop_proxy()->PostTaskAndReply(
792      FROM_HERE,
793      base::Bind(&HistoryBackend::QueryDownloads, history_backend_.get(), rows),
794      base::Bind(callback, base::Passed(&scoped_rows)));
795}
796
797// Handle updates for a particular download. This is a 'fire and forget'
798// operation, so we don't need to be called back.
799void HistoryService::UpdateDownload(const history::DownloadRow& data) {
800  DCHECK(thread_checker_.CalledOnValidThread());
801  ScheduleAndForget(PRIORITY_NORMAL, &HistoryBackend::UpdateDownload, data);
802}
803
804void HistoryService::RemoveDownloads(const std::set<uint32>& ids) {
805  DCHECK(thread_checker_.CalledOnValidThread());
806  ScheduleAndForget(PRIORITY_NORMAL,
807                    &HistoryBackend::RemoveDownloads, ids);
808}
809
810HistoryService::Handle HistoryService::QueryHistory(
811    const string16& text_query,
812    const history::QueryOptions& options,
813    CancelableRequestConsumerBase* consumer,
814    const QueryHistoryCallback& callback) {
815  DCHECK(thread_checker_.CalledOnValidThread());
816  return Schedule(PRIORITY_UI, &HistoryBackend::QueryHistory, consumer,
817                  new history::QueryHistoryRequest(callback),
818                  text_query, options);
819}
820
821HistoryService::Handle HistoryService::QueryRedirectsFrom(
822    const GURL& from_url,
823    CancelableRequestConsumerBase* consumer,
824    const QueryRedirectsCallback& callback) {
825  DCHECK(thread_checker_.CalledOnValidThread());
826  return Schedule(PRIORITY_UI, &HistoryBackend::QueryRedirectsFrom, consumer,
827      new history::QueryRedirectsRequest(callback), from_url);
828}
829
830HistoryService::Handle HistoryService::QueryRedirectsTo(
831    const GURL& to_url,
832    CancelableRequestConsumerBase* consumer,
833    const QueryRedirectsCallback& callback) {
834  DCHECK(thread_checker_.CalledOnValidThread());
835  return Schedule(PRIORITY_NORMAL, &HistoryBackend::QueryRedirectsTo, consumer,
836      new history::QueryRedirectsRequest(callback), to_url);
837}
838
839HistoryService::Handle HistoryService::GetVisibleVisitCountToHost(
840    const GURL& url,
841    CancelableRequestConsumerBase* consumer,
842    const GetVisibleVisitCountToHostCallback& callback) {
843  DCHECK(thread_checker_.CalledOnValidThread());
844  return Schedule(PRIORITY_UI, &HistoryBackend::GetVisibleVisitCountToHost,
845      consumer, new history::GetVisibleVisitCountToHostRequest(callback), url);
846}
847
848HistoryService::Handle HistoryService::QueryTopURLsAndRedirects(
849    int result_count,
850    CancelableRequestConsumerBase* consumer,
851    const QueryTopURLsAndRedirectsCallback& callback) {
852  DCHECK(thread_checker_.CalledOnValidThread());
853  return Schedule(PRIORITY_NORMAL, &HistoryBackend::QueryTopURLsAndRedirects,
854      consumer, new history::QueryTopURLsAndRedirectsRequest(callback),
855      result_count);
856}
857
858HistoryService::Handle HistoryService::QueryMostVisitedURLs(
859    int result_count,
860    int days_back,
861    CancelableRequestConsumerBase* consumer,
862    const QueryMostVisitedURLsCallback& callback) {
863  DCHECK(thread_checker_.CalledOnValidThread());
864  return Schedule(PRIORITY_NORMAL, &HistoryBackend::QueryMostVisitedURLs,
865                  consumer,
866                  new history::QueryMostVisitedURLsRequest(callback),
867                  result_count, days_back);
868}
869
870HistoryService::Handle HistoryService::QueryFilteredURLs(
871    int result_count,
872    const history::VisitFilter& filter,
873    bool extended_info,
874    CancelableRequestConsumerBase* consumer,
875    const QueryFilteredURLsCallback& callback) {
876  DCHECK(thread_checker_.CalledOnValidThread());
877  return Schedule(PRIORITY_NORMAL,
878                  &HistoryBackend::QueryFilteredURLs,
879                  consumer,
880                  new history::QueryFilteredURLsRequest(callback),
881                  result_count, filter, extended_info);
882}
883
884void HistoryService::Observe(int type,
885                             const content::NotificationSource& source,
886                             const content::NotificationDetails& details) {
887  DCHECK(thread_checker_.CalledOnValidThread());
888  if (!thread_)
889    return;
890
891  switch (type) {
892    case chrome::NOTIFICATION_HISTORY_URLS_DELETED: {
893      // Update the visited link system for deleted URLs. We will update the
894      // visited link system for added URLs as soon as we get the add
895      // notification (we don't have to wait for the backend, which allows us to
896      // be faster to update the state).
897      //
898      // For deleted URLs, we don't typically know what will be deleted since
899      // delete notifications are by time. We would also like to be more
900      // respectful of privacy and never tell the user something is gone when it
901      // isn't. Therefore, we update the delete URLs after the fact.
902      if (visitedlink_master_) {
903        content::Details<history::URLsDeletedDetails> deleted_details(details);
904
905        if (deleted_details->all_history) {
906          visitedlink_master_->DeleteAllURLs();
907        } else {
908          URLIteratorFromURLRows iterator(deleted_details->rows);
909          visitedlink_master_->DeleteURLs(&iterator);
910        }
911      }
912      break;
913    }
914
915    case chrome::NOTIFICATION_TEMPLATE_URL_REMOVED:
916      DeleteAllSearchTermsForKeyword(
917          *(content::Details<TemplateURLID>(details).ptr()));
918      break;
919
920    default:
921      NOTREACHED();
922  }
923}
924
925void HistoryService::RebuildTable(
926    const scoped_refptr<URLEnumerator>& enumerator) {
927  DCHECK(thread_checker_.CalledOnValidThread());
928  ScheduleAndForget(PRIORITY_NORMAL, &HistoryBackend::IterateURLs, enumerator);
929}
930
931bool HistoryService::Init(const base::FilePath& history_dir,
932                          BookmarkService* bookmark_service,
933                          bool no_db) {
934  DCHECK(thread_checker_.CalledOnValidThread());
935  if (!thread_->Start()) {
936    Cleanup();
937    return false;
938  }
939
940  history_dir_ = history_dir;
941  bookmark_service_ = bookmark_service;
942  no_db_ = no_db;
943
944  if (profile_) {
945    std::string languages =
946        profile_->GetPrefs()->GetString(prefs::kAcceptLanguages);
947    in_memory_url_index_.reset(
948        new history::InMemoryURLIndex(profile_, history_dir_, languages));
949    in_memory_url_index_->Init();
950  }
951
952  // Create the history backend.
953  LoadBackendIfNecessary();
954
955  if (visitedlink_master_) {
956    bool result = visitedlink_master_->Init();
957    DCHECK(result);
958  }
959
960  return true;
961}
962
963void HistoryService::ScheduleAutocomplete(HistoryURLProvider* provider,
964                                          HistoryURLProviderParams* params) {
965  DCHECK(thread_checker_.CalledOnValidThread());
966  ScheduleAndForget(PRIORITY_UI, &HistoryBackend::ScheduleAutocomplete,
967                    scoped_refptr<HistoryURLProvider>(provider), params);
968}
969
970void HistoryService::ScheduleTask(SchedulePriority priority,
971                                  const base::Closure& task) {
972  DCHECK(thread_checker_.CalledOnValidThread());
973  CHECK(thread_);
974  CHECK(thread_->message_loop());
975  // TODO(brettw): Do prioritization.
976  thread_->message_loop()->PostTask(FROM_HERE, task);
977}
978
979// static
980bool HistoryService::CanAddURL(const GURL& url) {
981  if (!url.is_valid())
982    return false;
983
984  // TODO: We should allow kChromeUIScheme URLs if they have been explicitly
985  // typed.  Right now, however, these are marked as typed even when triggered
986  // by a shortcut or menu action.
987  if (url.SchemeIs(content::kJavaScriptScheme) ||
988      url.SchemeIs(chrome::kChromeDevToolsScheme) ||
989      url.SchemeIs(chrome::kChromeNativeScheme) ||
990      url.SchemeIs(chrome::kChromeUIScheme) ||
991      url.SchemeIs(content::kViewSourceScheme) ||
992      url.SchemeIs(chrome::kChromeInternalScheme))
993    return false;
994
995  // Allow all about: and chrome: URLs except about:blank, since the user may
996  // like to see "chrome://memory/", etc. in their history and autocomplete.
997  if (url == GURL(content::kAboutBlankURL))
998    return false;
999
1000  return true;
1001}
1002
1003base::WeakPtr<HistoryService> HistoryService::AsWeakPtr() {
1004  DCHECK(thread_checker_.CalledOnValidThread());
1005  return weak_ptr_factory_.GetWeakPtr();
1006}
1007
1008syncer::SyncMergeResult HistoryService::MergeDataAndStartSyncing(
1009    syncer::ModelType type,
1010    const syncer::SyncDataList& initial_sync_data,
1011    scoped_ptr<syncer::SyncChangeProcessor> sync_processor,
1012    scoped_ptr<syncer::SyncErrorFactory> error_handler) {
1013  DCHECK(thread_checker_.CalledOnValidThread());
1014  DCHECK_EQ(type, syncer::HISTORY_DELETE_DIRECTIVES);
1015  delete_directive_handler_.Start(this, initial_sync_data,
1016                                  sync_processor.Pass());
1017  return syncer::SyncMergeResult(type);
1018}
1019
1020void HistoryService::StopSyncing(syncer::ModelType type) {
1021  DCHECK(thread_checker_.CalledOnValidThread());
1022  DCHECK_EQ(type, syncer::HISTORY_DELETE_DIRECTIVES);
1023  delete_directive_handler_.Stop();
1024}
1025
1026syncer::SyncDataList HistoryService::GetAllSyncData(
1027    syncer::ModelType type) const {
1028  DCHECK(thread_checker_.CalledOnValidThread());
1029  DCHECK_EQ(type, syncer::HISTORY_DELETE_DIRECTIVES);
1030  // TODO(akalin): Keep track of existing delete directives.
1031  return syncer::SyncDataList();
1032}
1033
1034syncer::SyncError HistoryService::ProcessSyncChanges(
1035    const tracked_objects::Location& from_here,
1036    const syncer::SyncChangeList& change_list) {
1037  delete_directive_handler_.ProcessSyncChanges(this, change_list);
1038  return syncer::SyncError();
1039}
1040
1041syncer::SyncError HistoryService::ProcessLocalDeleteDirective(
1042    const sync_pb::HistoryDeleteDirectiveSpecifics& delete_directive) {
1043  DCHECK(thread_checker_.CalledOnValidThread());
1044  return delete_directive_handler_.ProcessLocalDeleteDirective(
1045      delete_directive);
1046}
1047
1048void HistoryService::SetInMemoryBackend(
1049    int backend_id, scoped_ptr<history::InMemoryHistoryBackend> mem_backend) {
1050  DCHECK(thread_checker_.CalledOnValidThread());
1051  if (!history_backend_.get() || current_backend_id_ != backend_id) {
1052    DVLOG(1) << "Message from obsolete backend";
1053    // mem_backend is deleted.
1054    return;
1055  }
1056  DCHECK(!in_memory_backend_) << "Setting mem DB twice";
1057  in_memory_backend_.reset(mem_backend.release());
1058
1059  // The database requires additional initialization once we own it.
1060  in_memory_backend_->AttachToHistoryService(profile_);
1061}
1062
1063void HistoryService::NotifyProfileError(int backend_id,
1064                                        sql::InitStatus init_status) {
1065  DCHECK(thread_checker_.CalledOnValidThread());
1066  if (!history_backend_.get() || current_backend_id_ != backend_id) {
1067    DVLOG(1) << "Message from obsolete backend";
1068    return;
1069  }
1070  ShowProfileErrorDialog(
1071      (init_status == sql::INIT_FAILURE) ?
1072      IDS_COULDNT_OPEN_PROFILE_ERROR : IDS_PROFILE_TOO_NEW_ERROR);
1073}
1074
1075void HistoryService::DeleteURL(const GURL& url) {
1076  DCHECK(thread_checker_.CalledOnValidThread());
1077  // We will update the visited links when we observe the delete notifications.
1078  ScheduleAndForget(PRIORITY_NORMAL, &HistoryBackend::DeleteURL, url);
1079}
1080
1081void HistoryService::DeleteURLsForTest(const std::vector<GURL>& urls) {
1082  DCHECK(thread_checker_.CalledOnValidThread());
1083  // We will update the visited links when we observe the delete
1084  // notifications.
1085  ScheduleAndForget(PRIORITY_NORMAL, &HistoryBackend::DeleteURLs, urls);
1086}
1087
1088void HistoryService::ExpireHistoryBetween(
1089    const std::set<GURL>& restrict_urls,
1090    Time begin_time,
1091    Time end_time,
1092    const base::Closure& callback,
1093    CancelableTaskTracker* tracker) {
1094  DCHECK(thread_);
1095  DCHECK(thread_checker_.CalledOnValidThread());
1096  DCHECK(history_backend_.get());
1097  tracker->PostTaskAndReply(thread_->message_loop_proxy().get(),
1098                            FROM_HERE,
1099                            base::Bind(&HistoryBackend::ExpireHistoryBetween,
1100                                       history_backend_,
1101                                       restrict_urls,
1102                                       begin_time,
1103                                       end_time),
1104                            callback);
1105}
1106
1107void HistoryService::ExpireHistory(
1108    const std::vector<history::ExpireHistoryArgs>& expire_list,
1109    const base::Closure& callback,
1110    CancelableTaskTracker* tracker) {
1111  DCHECK(thread_);
1112  DCHECK(thread_checker_.CalledOnValidThread());
1113  DCHECK(history_backend_.get());
1114  tracker->PostTaskAndReply(
1115      thread_->message_loop_proxy().get(),
1116      FROM_HERE,
1117      base::Bind(&HistoryBackend::ExpireHistory, history_backend_, expire_list),
1118      callback);
1119}
1120
1121void HistoryService::ExpireLocalAndRemoteHistoryBetween(
1122    const std::set<GURL>& restrict_urls,
1123    Time begin_time,
1124    Time end_time,
1125    const base::Closure& callback,
1126    CancelableTaskTracker* tracker) {
1127  // TODO(dubroy): This should be factored out into a separate class that
1128  // dispatches deletions to the proper places.
1129
1130  history::WebHistoryService* web_history =
1131      WebHistoryServiceFactory::GetForProfile(profile_);
1132  if (web_history) {
1133    // TODO(dubroy): This API does not yet support deletion of specific URLs.
1134    DCHECK(restrict_urls.empty());
1135
1136    delete_directive_handler_.CreateDeleteDirectives(
1137        std::set<int64>(), begin_time, end_time);
1138
1139    // Attempt online deletion from the history server, but ignore the result.
1140    // Deletion directives ensure that the results will eventually be deleted.
1141    // Pass ownership of the request to the callback.
1142    scoped_ptr<history::WebHistoryService::Request> request =
1143        web_history->ExpireHistoryBetween(
1144            restrict_urls, begin_time, end_time,
1145            base::Bind(&ExpireWebHistoryComplete));
1146
1147    // The request will be freed when the callback is called.
1148    CHECK(request.release());
1149  }
1150  ExpireHistoryBetween(restrict_urls, begin_time, end_time, callback, tracker);
1151}
1152
1153void HistoryService::BroadcastNotificationsHelper(
1154    int type,
1155    history::HistoryDetails* details) {
1156  DCHECK(thread_checker_.CalledOnValidThread());
1157  // TODO(evanm): this is currently necessitated by generate_profile, which
1158  // runs without a browser process. generate_profile should really create
1159  // a browser process, at which point this check can then be nuked.
1160  if (!g_browser_process)
1161    return;
1162
1163  if (!thread_)
1164    return;
1165
1166  // The source of all of our notifications is the profile. Note that this
1167  // pointer is NULL in unit tests.
1168  content::Source<Profile> source(profile_);
1169
1170  // The details object just contains the pointer to the object that the
1171  // backend has allocated for us. The receiver of the notification will cast
1172  // this to the proper type.
1173  content::Details<history::HistoryDetails> det(details);
1174
1175  content::NotificationService::current()->Notify(type, source, det);
1176}
1177
1178void HistoryService::LoadBackendIfNecessary() {
1179  DCHECK(thread_checker_.CalledOnValidThread());
1180  if (!thread_ || history_backend_.get())
1181    return;  // Failed to init, or already started loading.
1182
1183  ++current_backend_id_;
1184  scoped_refptr<HistoryBackend> backend(
1185      new HistoryBackend(history_dir_,
1186                         current_backend_id_,
1187                         new BackendDelegate(
1188                             weak_ptr_factory_.GetWeakPtr(),
1189                             base::ThreadTaskRunnerHandle::Get(),
1190                             profile_),
1191                         bookmark_service_));
1192  history_backend_.swap(backend);
1193
1194  // There may not be a profile when unit testing.
1195  std::string languages;
1196  if (profile_) {
1197    PrefService* prefs = profile_->GetPrefs();
1198    languages = prefs->GetString(prefs::kAcceptLanguages);
1199  }
1200  ScheduleAndForget(PRIORITY_UI, &HistoryBackend::Init, languages, no_db_);
1201}
1202
1203void HistoryService::OnDBLoaded(int backend_id) {
1204  DCHECK(thread_checker_.CalledOnValidThread());
1205  if (!history_backend_.get() || current_backend_id_ != backend_id) {
1206    DVLOG(1) << "Message from obsolete backend";
1207    return;
1208  }
1209  backend_loaded_ = true;
1210  content::NotificationService::current()->Notify(
1211      chrome::NOTIFICATION_HISTORY_LOADED,
1212      content::Source<Profile>(profile_),
1213      content::Details<HistoryService>(this));
1214}
1215
1216bool HistoryService::GetRowForURL(const GURL& url, history::URLRow* url_row) {
1217  DCHECK(thread_checker_.CalledOnValidThread());
1218  history::URLDatabase* db = InMemoryDatabase();
1219  return db && (db->GetRowForURL(url, url_row) != 0);
1220}
1221
1222void HistoryService::AddVisitDatabaseObserver(
1223    history::VisitDatabaseObserver* observer) {
1224  DCHECK(thread_checker_.CalledOnValidThread());
1225  visit_database_observers_.AddObserver(observer);
1226}
1227
1228void HistoryService::RemoveVisitDatabaseObserver(
1229    history::VisitDatabaseObserver* observer) {
1230  DCHECK(thread_checker_.CalledOnValidThread());
1231  visit_database_observers_.RemoveObserver(observer);
1232}
1233
1234void HistoryService::NotifyVisitDBObserversOnAddVisit(
1235    const history::BriefVisitInfo& info) {
1236  DCHECK(thread_checker_.CalledOnValidThread());
1237  FOR_EACH_OBSERVER(history::VisitDatabaseObserver, visit_database_observers_,
1238                    OnAddVisit(info));
1239}
1240