Adding upstream version 110.0.1.upstream/110.0.1upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 2801 insertions, 0 deletions

diff --git a/toolkit/components/places/Database.cpp b/toolkit/components/places/Database.cpp
new file mode 100644
index 0000000000..f12c4b330c
--- /dev/null
+++ b/toolkit/components/places/Database.cpp
@@ -0,0 +1,2801 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "mozilla/ArrayUtils.h"
+#include "mozilla/Attributes.h"
+#include "mozilla/DebugOnly.h"
+#include "mozilla/ScopeExit.h"
+#include "mozilla/SpinEventLoopUntil.h"
+#include "mozilla/JSONStringWriteFuncs.h"
+
+#include "Database.h"
+
+#include "nsIInterfaceRequestorUtils.h"
+#include "nsIFile.h"
+
+#include "nsNavBookmarks.h"
+#include "nsNavHistory.h"
+#include "nsPlacesTables.h"
+#include "nsPlacesIndexes.h"
+#include "nsPlacesTriggers.h"
+#include "nsPlacesMacros.h"
+#include "nsVariant.h"
+#include "SQLFunctions.h"
+#include "Helpers.h"
+#include "nsFaviconService.h"
+
+#include "nsAppDirectoryServiceDefs.h"
+#include "nsDirectoryServiceUtils.h"
+#include "prenv.h"
+#include "prsystem.h"
+#include "nsPrintfCString.h"
+#include "mozilla/Preferences.h"
+#include "mozilla/Services.h"
+#include "mozilla/Unused.h"
+#include "mozIStorageService.h"
+#include "prtime.h"
+
+#include "nsXULAppAPI.h"
+
+// Time between corrupt database backups.
+#define RECENT_BACKUP_TIME_MICROSEC (int64_t)86400 * PR_USEC_PER_SEC  // 24H
+
+// Filename of the database.
+#define DATABASE_FILENAME u"places.sqlite"_ns
+// Filename of the icons database.
+#define DATABASE_FAVICONS_FILENAME u"favicons.sqlite"_ns
+
+// Set to the database file name when it was found corrupt by a previous
+// maintenance run.
+#define PREF_FORCE_DATABASE_REPLACEMENT \
+  "places.database.replaceDatabaseOnStartup"
+
+// Whether on corruption we should try to fix the database by cloning it.
+#define PREF_DATABASE_CLONEONCORRUPTION "places.database.cloneOnCorruption"
+
+// Set to specify the size of the places database growth increments in kibibytes
+#define PREF_GROWTH_INCREMENT_KIB "places.database.growthIncrementKiB"
+
+// Set to disable the default robust storage and use volatile, in-memory
+// storage without robust transaction flushing guarantees. This makes
+// SQLite use much less I/O at the cost of losing data when things crash.
+// The pref is only honored if an environment variable is set. The env
+// variable is intentionally named something scary to help prevent someone
+// from thinking it is a useful performance optimization they should enable.
+#define PREF_DISABLE_DURABILITY "places.database.disableDurability"
+
+#define PREF_PREVIEWS_ENABLED "places.previews.enabled"
+
+#define ENV_ALLOW_CORRUPTION \
+  "ALLOW_PLACES_DATABASE_TO_LOSE_DATA_AND_BECOME_CORRUPT"
+
+#define PREF_MIGRATE_V52_ORIGIN_FRECENCIES \
+  "places.database.migrateV52OriginFrecencies"
+
+// Maximum size for the WAL file.
+// For performance reasons this should be as large as possible, so that more
+// transactions can fit into it, and the checkpoint cost is paid less often.
+// At the same time, since we use synchronous = NORMAL, an fsync happens only
+// at checkpoint time, so we don't want the WAL to grow too much and risk to
+// lose all the contained transactions on a crash.
+#define DATABASE_MAX_WAL_BYTES 2048000
+
+// Since exceeding the journal limit will cause a truncate, we allow a slightly
+// larger limit than DATABASE_MAX_WAL_BYTES to reduce the number of truncates.
+// This is the number of bytes the journal can grow over the maximum wal size
+// before being truncated.
+#define DATABASE_JOURNAL_OVERHEAD_BYTES 2048000
+
+#define BYTES_PER_KIBIBYTE 1024
+
+// How much time Sqlite can wait before returning a SQLITE_BUSY error.
+#define DATABASE_BUSY_TIMEOUT_MS 100
+
+// This annotation is no longer used & is obsolete, but here for migration.
+#define LAST_USED_ANNO "bookmarkPropertiesDialog/folderLastUsed"_ns
+// This is key in the meta table that the LAST_USED_ANNO is migrated to.
+#define LAST_USED_FOLDERS_META_KEY "places/bookmarks/edit/lastusedfolder"_ns
+
+// We use a fixed title for the mobile root to avoid marking the database as
+// corrupt if we can't look up the localized title in the string bundle. Sync
+// sets the title to the localized version when it creates the left pane query.
+#define MOBILE_ROOT_TITLE "mobile"
+
+// Legacy item annotation used by the old Sync engine.
+#define SYNC_PARENT_ANNO "sync/parent"
+
+using namespace mozilla;
+
+namespace mozilla {
+namespace places {
+
+namespace {
+
+////////////////////////////////////////////////////////////////////////////////
+//// Helpers
+
+/**
+ * Get the filename for a corrupt database.
+ */
+nsString getCorruptFilename(const nsString& aDbFilename) {
+  return aDbFilename + u".corrupt"_ns;
+}
+/**
+ * Get the filename for a recover database.
+ */
+nsString getRecoverFilename(const nsString& aDbFilename) {
+  return aDbFilename + u".recover"_ns;
+}
+
+/**
+ * Checks whether exists a corrupt database file created not longer than
+ * RECENT_BACKUP_TIME_MICROSEC ago.
+ */
+bool isRecentCorruptFile(const nsCOMPtr<nsIFile>& aCorruptFile) {
+  MOZ_ASSERT(NS_IsMainThread());
+  bool fileExists = false;
+  if (NS_FAILED(aCorruptFile->Exists(&fileExists)) || !fileExists) {
+    return false;
+  }
+  PRTime lastMod = 0;
+  if (NS_FAILED(aCorruptFile->GetLastModifiedTime(&lastMod)) || lastMod <= 0 ||
+      (PR_Now() - lastMod) > RECENT_BACKUP_TIME_MICROSEC) {
+    return false;
+  }
+  return true;
+}
+
+/**
+ * Sets the connection journal mode to one of the JOURNAL_* types.
+ *
+ * @param aDBConn
+ *        The database connection.
+ * @param aJournalMode
+ *        One of the JOURNAL_* types.
+ * @returns the current journal mode.
+ * @note this may return a different journal mode than the required one, since
+ *       setting it may fail.
+ */
+enum JournalMode SetJournalMode(nsCOMPtr<mozIStorageConnection>& aDBConn,
+                                enum JournalMode aJournalMode) {
+  MOZ_ASSERT(NS_IsMainThread());
+  nsAutoCString journalMode;
+  switch (aJournalMode) {
+    default:
+      MOZ_FALLTHROUGH_ASSERT("Trying to set an unknown journal mode.");
+      // Fall through to the default DELETE journal.
+    case JOURNAL_DELETE:
+      journalMode.AssignLiteral("delete");
+      break;
+    case JOURNAL_TRUNCATE:
+      journalMode.AssignLiteral("truncate");
+      break;
+    case JOURNAL_MEMORY:
+      journalMode.AssignLiteral("memory");
+      break;
+    case JOURNAL_WAL:
+      journalMode.AssignLiteral("wal");
+      break;
+  }
+
+  nsCOMPtr<mozIStorageStatement> statement;
+  nsAutoCString query(MOZ_STORAGE_UNIQUIFY_QUERY_STR "PRAGMA journal_mode = ");
+  query.Append(journalMode);
+  aDBConn->CreateStatement(query, getter_AddRefs(statement));
+  NS_ENSURE_TRUE(statement, JOURNAL_DELETE);
+
+  bool hasResult = false;
+  if (NS_SUCCEEDED(statement->ExecuteStep(&hasResult)) && hasResult &&
+      NS_SUCCEEDED(statement->GetUTF8String(0, journalMode))) {
+    if (journalMode.EqualsLiteral("delete")) {
+      return JOURNAL_DELETE;
+    }
+    if (journalMode.EqualsLiteral("truncate")) {
+      return JOURNAL_TRUNCATE;
+    }
+    if (journalMode.EqualsLiteral("memory")) {
+      return JOURNAL_MEMORY;
+    }
+    if (journalMode.EqualsLiteral("wal")) {
+      return JOURNAL_WAL;
+    }
+    MOZ_ASSERT(false, "Got an unknown journal mode.");
+  }
+
+  return JOURNAL_DELETE;
+}
+
+nsresult CreateRoot(nsCOMPtr<mozIStorageConnection>& aDBConn,
+                    const nsCString& aRootName, const nsCString& aGuid,
+                    const nsCString& titleString, const int32_t position,
+                    int64_t& newId) {
+  MOZ_ASSERT(NS_IsMainThread());
+
+  // A single creation timestamp for all roots so that the root folder's
+  // last modification time isn't earlier than its childrens' creation time.
+  static PRTime timestamp = 0;
+  if (!timestamp) timestamp = RoundedPRNow();
+
+  // Create a new bookmark folder for the root.
+  nsCOMPtr<mozIStorageStatement> stmt;
+  nsresult rv = aDBConn->CreateStatement(
+      nsLiteralCString(
+          "INSERT INTO moz_bookmarks "
+          "(type, position, title, dateAdded, lastModified, guid, parent, "
+          "syncChangeCounter, syncStatus) "
+          "VALUES (:item_type, :item_position, :item_title,"
+          ":date_added, :last_modified, :guid, "
+          "IFNULL((SELECT id FROM moz_bookmarks WHERE parent = 0), 0), "
+          "1, :sync_status)"),
+      getter_AddRefs(stmt));
+  if (NS_FAILED(rv)) return rv;
+
+  rv = stmt->BindInt32ByName("item_type"_ns,
+                             nsINavBookmarksService::TYPE_FOLDER);
+  if (NS_FAILED(rv)) return rv;
+  rv = stmt->BindInt32ByName("item_position"_ns, position);
+  if (NS_FAILED(rv)) return rv;
+  rv = stmt->BindUTF8StringByName("item_title"_ns, titleString);
+  if (NS_FAILED(rv)) return rv;
+  rv = stmt->BindInt64ByName("date_added"_ns, timestamp);
+  if (NS_FAILED(rv)) return rv;
+  rv = stmt->BindInt64ByName("last_modified"_ns, timestamp);
+  if (NS_FAILED(rv)) return rv;
+  rv = stmt->BindUTF8StringByName("guid"_ns, aGuid);
+  if (NS_FAILED(rv)) return rv;
+  rv = stmt->BindInt32ByName("sync_status"_ns,
+                             nsINavBookmarksService::SYNC_STATUS_NEW);
+  if (NS_FAILED(rv)) return rv;
+  rv = stmt->Execute();
+  if (NS_FAILED(rv)) return rv;
+
+  newId = nsNavBookmarks::sLastInsertedItemId;
+  return NS_OK;
+}
+
+nsresult SetupDurability(nsCOMPtr<mozIStorageConnection>& aDBConn,
+                         int32_t aDBPageSize) {
+  nsresult rv;
+  if (PR_GetEnv(ENV_ALLOW_CORRUPTION) &&
+      Preferences::GetBool(PREF_DISABLE_DURABILITY, false)) {
+    // Volatile storage was requested. Use the in-memory journal (no
+    // filesystem I/O) and don't sync the filesystem after writing.
+    SetJournalMode(aDBConn, JOURNAL_MEMORY);
+    rv = aDBConn->ExecuteSimpleSQL("PRAGMA synchronous = OFF"_ns);
+    NS_ENSURE_SUCCESS(rv, rv);
+  } else {
+    // Be sure to set journal mode after page_size.  WAL would prevent the
+    // change otherwise.
+    if (JOURNAL_WAL == SetJournalMode(aDBConn, JOURNAL_WAL)) {
+      // Set the WAL journal size limit.
+      int32_t checkpointPages =
+          static_cast<int32_t>(DATABASE_MAX_WAL_BYTES / aDBPageSize);
+      nsAutoCString checkpointPragma("PRAGMA wal_autocheckpoint = ");
+      checkpointPragma.AppendInt(checkpointPages);
+      rv = aDBConn->ExecuteSimpleSQL(checkpointPragma);
+      NS_ENSURE_SUCCESS(rv, rv);
+    } else {
+      // Ignore errors, if we fail here the database could be considered corrupt
+      // and we won't be able to go on, even if it's just matter of a bogus file
+      // system.  The default mode (DELETE) will be fine in such a case.
+      (void)SetJournalMode(aDBConn, JOURNAL_TRUNCATE);
+
+      // Set synchronous to FULL to ensure maximum data integrity, even in
+      // case of crashes or unclean shutdowns.
+      rv = aDBConn->ExecuteSimpleSQL("PRAGMA synchronous = FULL"_ns);
+      NS_ENSURE_SUCCESS(rv, rv);
+    }
+  }
+
+  // The journal is usually free to grow for performance reasons, but it never
+  // shrinks back.  Since the space taken may be problematic, limit its size.
+  nsAutoCString journalSizePragma("PRAGMA journal_size_limit = ");
+  journalSizePragma.AppendInt(DATABASE_MAX_WAL_BYTES +
+                              DATABASE_JOURNAL_OVERHEAD_BYTES);
+  (void)aDBConn->ExecuteSimpleSQL(journalSizePragma);
+
+  // Grow places in |growthIncrementKiB| increments to limit fragmentation on
+  // disk. By default, it's 5 MB.
+  int32_t growthIncrementKiB =
+      Preferences::GetInt(PREF_GROWTH_INCREMENT_KIB, 5 * BYTES_PER_KIBIBYTE);
+  if (growthIncrementKiB > 0) {
+    (void)aDBConn->SetGrowthIncrement(growthIncrementKiB * BYTES_PER_KIBIBYTE,
+                                      ""_ns);
+  }
+  return NS_OK;
+}
+
+nsresult AttachDatabase(nsCOMPtr<mozIStorageConnection>& aDBConn,
+                        const nsACString& aPath, const nsACString& aName) {
+  nsCOMPtr<mozIStorageStatement> stmt;
+  nsresult rv = aDBConn->CreateStatement("ATTACH DATABASE :path AS "_ns + aName,
+                                         getter_AddRefs(stmt));
+  NS_ENSURE_SUCCESS(rv, rv);
+  rv = stmt->BindUTF8StringByName("path"_ns, aPath);
+  NS_ENSURE_SUCCESS(rv, rv);
+  rv = stmt->Execute();
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  // The journal limit must be set apart for each database.
+  nsAutoCString journalSizePragma("PRAGMA favicons.journal_size_limit = ");
+  journalSizePragma.AppendInt(DATABASE_MAX_WAL_BYTES +
+                              DATABASE_JOURNAL_OVERHEAD_BYTES);
+  Unused << aDBConn->ExecuteSimpleSQL(journalSizePragma);
+
+  return NS_OK;
+}
+
+}  // namespace
+
+////////////////////////////////////////////////////////////////////////////////
+//// Database
+
+PLACES_FACTORY_SINGLETON_IMPLEMENTATION(Database, gDatabase)
+
+NS_IMPL_ISUPPORTS(Database, nsIObserver, nsISupportsWeakReference)
+
+Database::Database()
+    : mMainThreadStatements(mMainConn),
+      mMainThreadAsyncStatements(mMainConn),
+      mAsyncThreadStatements(mMainConn),
+      mDBPageSize(0),
+      mDatabaseStatus(nsINavHistoryService::DATABASE_STATUS_OK),
+      mClosed(false),
+      mClientsShutdown(new ClientsShutdownBlocker()),
+      mConnectionShutdown(new ConnectionShutdownBlocker(this)),
+      mMaxUrlLength(0),
+      mCacheObservers(TOPIC_PLACES_INIT_COMPLETE),
+      mRootId(-1),
+      mMenuRootId(-1),
+      mTagsRootId(-1),
+      mUnfiledRootId(-1),
+      mToolbarRootId(-1),
+      mMobileRootId(-1) {
+  MOZ_ASSERT(!XRE_IsContentProcess(),
+             "Cannot instantiate Places in the content process");
+  // Attempting to create two instances of the service?
+  MOZ_ASSERT(!gDatabase);
+  gDatabase = this;
+}
+
+already_AddRefed<nsIAsyncShutdownClient>
+Database::GetProfileChangeTeardownPhase() {
+  nsCOMPtr<nsIAsyncShutdownService> asyncShutdownSvc =
+      services::GetAsyncShutdownService();
+  MOZ_ASSERT(asyncShutdownSvc);
+  if (NS_WARN_IF(!asyncShutdownSvc)) {
+    return nullptr;
+  }
+
+  // Consumers of Places should shutdown before us, at profile-change-teardown.
+  nsCOMPtr<nsIAsyncShutdownClient> shutdownPhase;
+  DebugOnly<nsresult> rv =
+      asyncShutdownSvc->GetProfileChangeTeardown(getter_AddRefs(shutdownPhase));
+  MOZ_ASSERT(NS_SUCCEEDED(rv));
+  return shutdownPhase.forget();
+}
+
+already_AddRefed<nsIAsyncShutdownClient>
+Database::GetProfileBeforeChangePhase() {
+  nsCOMPtr<nsIAsyncShutdownService> asyncShutdownSvc =
+      services::GetAsyncShutdownService();
+  MOZ_ASSERT(asyncShutdownSvc);
+  if (NS_WARN_IF(!asyncShutdownSvc)) {
+    return nullptr;
+  }
+
+  // Consumers of Places should shutdown before us, at profile-change-teardown.
+  nsCOMPtr<nsIAsyncShutdownClient> shutdownPhase;
+  DebugOnly<nsresult> rv =
+      asyncShutdownSvc->GetProfileBeforeChange(getter_AddRefs(shutdownPhase));
+  MOZ_ASSERT(NS_SUCCEEDED(rv));
+  return shutdownPhase.forget();
+}
+
+Database::~Database() = default;
+
+already_AddRefed<mozIStorageAsyncStatement> Database::GetAsyncStatement(
+    const nsACString& aQuery) {
+  if (PlacesShutdownBlocker::sIsStarted || NS_FAILED(EnsureConnection())) {
+    return nullptr;
+  }
+
+  MOZ_ASSERT(NS_IsMainThread());
+  return mMainThreadAsyncStatements.GetCachedStatement(aQuery);
+}
+
+already_AddRefed<mozIStorageStatement> Database::GetStatement(
+    const nsACString& aQuery) {
+  if (PlacesShutdownBlocker::sIsStarted) {
+    return nullptr;
+  }
+  if (NS_IsMainThread()) {
+    if (NS_FAILED(EnsureConnection())) {
+      return nullptr;
+    }
+    return mMainThreadStatements.GetCachedStatement(aQuery);
+  }
+  // In the async case, the connection must have been started on the main-thread
+  // already.
+  MOZ_ASSERT(mMainConn);
+  return mAsyncThreadStatements.GetCachedStatement(aQuery);
+}
+
+already_AddRefed<nsIAsyncShutdownClient> Database::GetClientsShutdown() {
+  if (mClientsShutdown) return mClientsShutdown->GetClient();
+  return nullptr;
+}
+
+already_AddRefed<nsIAsyncShutdownClient> Database::GetConnectionShutdown() {
+  if (mConnectionShutdown) return mConnectionShutdown->GetClient();
+  return nullptr;
+}
+
+// static
+already_AddRefed<Database> Database::GetDatabase() {
+  if (PlacesShutdownBlocker::sIsStarted) {
+    return nullptr;
+  }
+  return GetSingleton();
+}
+
+nsresult Database::Init() {
+  MOZ_ASSERT(NS_IsMainThread());
+
+  // DO NOT FAIL HERE, otherwise we would never break the cycle between this
+  // object and the shutdown blockers, causing unexpected leaks.
+
+  {
+    // First of all Places clients should block profile-change-teardown.
+    nsCOMPtr<nsIAsyncShutdownClient> shutdownPhase =
+        GetProfileChangeTeardownPhase();
+    MOZ_ASSERT(shutdownPhase);
+    if (shutdownPhase) {
+      DebugOnly<nsresult> rv = shutdownPhase->AddBlocker(
+          static_cast<nsIAsyncShutdownBlocker*>(mClientsShutdown.get()),
+          NS_LITERAL_STRING_FROM_CSTRING(__FILE__), __LINE__, u""_ns);
+      MOZ_ASSERT(NS_SUCCEEDED(rv));
+    }
+  }
+
+  {
+    // Then connection closing should block profile-before-change.
+    nsCOMPtr<nsIAsyncShutdownClient> shutdownPhase =
+        GetProfileBeforeChangePhase();
+    MOZ_ASSERT(shutdownPhase);
+    if (shutdownPhase) {
+      DebugOnly<nsresult> rv = shutdownPhase->AddBlocker(
+          static_cast<nsIAsyncShutdownBlocker*>(mConnectionShutdown.get()),
+          NS_LITERAL_STRING_FROM_CSTRING(__FILE__), __LINE__, u""_ns);
+      MOZ_ASSERT(NS_SUCCEEDED(rv));
+    }
+  }
+
+  // Finally observe profile shutdown notifications.
+  nsCOMPtr<nsIObserverService> os = mozilla::services::GetObserverService();
+  if (os) {
+    (void)os->AddObserver(this, TOPIC_PROFILE_CHANGE_TEARDOWN, true);
+  }
+  return NS_OK;
+}
+
+nsresult Database::EnsureConnection() {
+  // Run this only once.
+  if (mMainConn ||
+      mDatabaseStatus == nsINavHistoryService::DATABASE_STATUS_LOCKED) {
+    return NS_OK;
+  }
+  // Don't try to create a database too late.
+  if (PlacesShutdownBlocker::sIsStarted) {
+    return NS_ERROR_FAILURE;
+  }
+
+  MOZ_ASSERT(NS_IsMainThread(),
+             "Database initialization must happen on the main-thread");
+
+  {
+    bool initSucceeded = false;
+    auto notify = MakeScopeExit([&]() {
+      // If the database connection cannot be opened, it may just be locked
+      // by third parties.  Set a locked state.
+      if (!initSucceeded) {
+        mMainConn = nullptr;
+        mDatabaseStatus = nsINavHistoryService::DATABASE_STATUS_LOCKED;
+      }
+      // Notify at the next tick, to avoid re-entrancy problems.
+      NS_DispatchToMainThread(
+          NewRunnableMethod("places::Database::EnsureConnection()", this,
+                            &Database::NotifyConnectionInitalized));
+    });
+
+    nsCOMPtr<mozIStorageService> storage =
+        do_GetService(MOZ_STORAGE_SERVICE_CONTRACTID);
+    NS_ENSURE_STATE(storage);
+
+    nsCOMPtr<nsIFile> profileDir;
+    nsresult rv = NS_GetSpecialDirectory(NS_APP_USER_PROFILE_50_DIR,
+                                         getter_AddRefs(profileDir));
+    NS_ENSURE_SUCCESS(rv, rv);
+
+    nsCOMPtr<nsIFile> databaseFile;
+    rv = profileDir->Clone(getter_AddRefs(databaseFile));
+    NS_ENSURE_SUCCESS(rv, rv);
+    rv = databaseFile->Append(DATABASE_FILENAME);
+    NS_ENSURE_SUCCESS(rv, rv);
+    bool databaseExisted = false;
+    rv = databaseFile->Exists(&databaseExisted);
+    NS_ENSURE_SUCCESS(rv, rv);
+
+    nsAutoString corruptDbName;
+    if (NS_SUCCEEDED(Preferences::GetString(PREF_FORCE_DATABASE_REPLACEMENT,
+                                            corruptDbName)) &&
+        !corruptDbName.IsEmpty()) {
+      // If this pref is set, maintenance required a database replacement, due
+      // to integrity corruption. Be sure to clear the pref to avoid handling it
+      // more than once.
+      (void)Preferences::ClearUser(PREF_FORCE_DATABASE_REPLACEMENT);
+
+      // The database is corrupt, backup and replace it with a new one.
+      nsCOMPtr<nsIFile> fileToBeReplaced;
+      bool fileExists = false;
+      if (NS_SUCCEEDED(profileDir->Clone(getter_AddRefs(fileToBeReplaced))) &&
+          NS_SUCCEEDED(fileToBeReplaced->Exists(&fileExists)) && fileExists) {
+        rv = BackupAndReplaceDatabaseFile(storage, corruptDbName, true, false);
+        NS_ENSURE_SUCCESS(rv, rv);
+      }
+    }
+
+    // Open the database file.  If it does not exist a new one will be created.
+    // Use an unshared connection, it will consume more memory but avoid shared
+    // cache contentions across threads.
+    rv = storage->OpenUnsharedDatabase(databaseFile,
+                                       mozIStorageService::CONNECTION_DEFAULT,
+                                       getter_AddRefs(mMainConn));
+    if (NS_SUCCEEDED(rv) && !databaseExisted) {
+      mDatabaseStatus = nsINavHistoryService::DATABASE_STATUS_CREATE;
+    } else if (rv == NS_ERROR_FILE_CORRUPTED) {
+      // The database is corrupt, backup and replace it with a new one.
+      rv = BackupAndReplaceDatabaseFile(storage, DATABASE_FILENAME, true, true);
+      // Fallback to catch-all handler.
+    }
+    NS_ENSURE_SUCCESS(rv, rv);
+
+    // Initialize the database schema.  In case of failure the existing schema
+    // is is corrupt or incoherent, thus the database should be replaced.
+    bool databaseMigrated = false;
+    rv = SetupDatabaseConnection(storage);
+    bool shouldTryToCloneDb = true;
+    if (NS_SUCCEEDED(rv)) {
+      // Failing to initialize the schema may indicate a corruption.
+      rv = InitSchema(&databaseMigrated);
+      if (NS_FAILED(rv)) {
+        // Cloning the db on a schema migration may not be a good idea, since we
+        // may end up cloning the schema problems.
+        shouldTryToCloneDb = false;
+        if (rv == NS_ERROR_STORAGE_BUSY || rv == NS_ERROR_FILE_IS_LOCKED ||
+            rv == NS_ERROR_FILE_NO_DEVICE_SPACE ||
+            rv == NS_ERROR_OUT_OF_MEMORY) {
+          // The database is not corrupt, though some migration step failed.
+          // This may be caused by concurrent use of sync and async Storage APIs
+          // or by a system issue.
+          // The best we can do is trying again. If it should still fail, Places
+          // won't work properly and will be handled as LOCKED.
+          rv = InitSchema(&databaseMigrated);
+          if (NS_FAILED(rv)) {
+            rv = NS_ERROR_FILE_IS_LOCKED;
+          }
+        } else {
+          rv = NS_ERROR_FILE_CORRUPTED;
+        }
+      }
+    }
+    if (NS_WARN_IF(NS_FAILED(rv))) {
+      if (rv != NS_ERROR_FILE_IS_LOCKED) {
+        mDatabaseStatus = nsINavHistoryService::DATABASE_STATUS_CORRUPT;
+      }
+      // Some errors may not indicate a database corruption, for those cases we
+      // just bail out without throwing away a possibly valid places.sqlite.
+      if (rv == NS_ERROR_FILE_CORRUPTED) {
+        // Since we don't know which database is corrupt, we must replace both.
+        rv = BackupAndReplaceDatabaseFile(storage, DATABASE_FAVICONS_FILENAME,
+                                          false, false);
+        NS_ENSURE_SUCCESS(rv, rv);
+        rv = BackupAndReplaceDatabaseFile(storage, DATABASE_FILENAME,
+                                          shouldTryToCloneDb, true);
+        NS_ENSURE_SUCCESS(rv, rv);
+        // Try to initialize the new database again.
+        rv = SetupDatabaseConnection(storage);
+        NS_ENSURE_SUCCESS(rv, rv);
+        rv = InitSchema(&databaseMigrated);
+      }
+      // Bail out if we couldn't fix the database.
+      NS_ENSURE_SUCCESS(rv, rv);
+    }
+
+    if (databaseMigrated) {
+      mDatabaseStatus = nsINavHistoryService::DATABASE_STATUS_UPGRADED;
+    }
+
+    // Initialize here all the items that are not part of the on-disk database,
+    // like views, temp triggers or temp tables.  The database should not be
+    // considered corrupt if any of the following fails.
+
+    rv = InitTempEntities();
+    NS_ENSURE_SUCCESS(rv, rv);
+
+    rv = CheckRoots();
+    NS_ENSURE_SUCCESS(rv, rv);
+
+    initSucceeded = true;
+  }
+  return NS_OK;
+}
+
+nsresult Database::NotifyConnectionInitalized() {
+  MOZ_ASSERT(NS_IsMainThread());
+  // Notify about Places initialization.
+  nsCOMArray<nsIObserver> entries;
+  mCacheObservers.GetEntries(entries);
+  for (int32_t idx = 0; idx < entries.Count(); ++idx) {
+    MOZ_ALWAYS_SUCCEEDS(
+        entries[idx]->Observe(nullptr, TOPIC_PLACES_INIT_COMPLETE, nullptr));
+  }
+  nsCOMPtr<nsIObserverService> obs = mozilla::services::GetObserverService();
+  if (obs) {
+    MOZ_ALWAYS_SUCCEEDS(
+        obs->NotifyObservers(nullptr, TOPIC_PLACES_INIT_COMPLETE, nullptr));
+  }
+  return NS_OK;
+}
+
+nsresult Database::EnsureFaviconsDatabaseAttached(
+    const nsCOMPtr<mozIStorageService>& aStorage) {
+  MOZ_ASSERT(NS_IsMainThread());
+
+  nsCOMPtr<nsIFile> databaseFile;
+  NS_GetSpecialDirectory(NS_APP_USER_PROFILE_50_DIR,
+                         getter_AddRefs(databaseFile));
+  NS_ENSURE_STATE(databaseFile);
+  nsresult rv = databaseFile->Append(DATABASE_FAVICONS_FILENAME);
+  NS_ENSURE_SUCCESS(rv, rv);
+  nsString iconsPath;
+  rv = databaseFile->GetPath(iconsPath);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  bool fileExists = false;
+  if (NS_SUCCEEDED(databaseFile->Exists(&fileExists)) && fileExists) {
+    return AttachDatabase(mMainConn, NS_ConvertUTF16toUTF8(iconsPath),
+                          "favicons"_ns);
+  }
+
+  // Open the database file, this will also create it.
+  nsCOMPtr<mozIStorageConnection> conn;
+  rv = aStorage->OpenUnsharedDatabase(databaseFile,
+                                      mozIStorageService::CONNECTION_DEFAULT,
+                                      getter_AddRefs(conn));
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  {
+    // Ensure we'll close the connection when done.
+    auto cleanup = MakeScopeExit([&]() {
+      // We cannot use AsyncClose() here, because by the time we try to ATTACH
+      // this database, its transaction could be still be running and that would
+      // cause the ATTACH query to fail.
+      MOZ_ALWAYS_TRUE(NS_SUCCEEDED(conn->Close()));
+    });
+
+    // Enable incremental vacuum for this database. Since it will contain even
+    // large blobs and can be cleared with history, it's worth to have it.
+    // Note that it will be necessary to manually use PRAGMA incremental_vacuum.
+    rv = conn->ExecuteSimpleSQL("PRAGMA auto_vacuum = INCREMENTAL"_ns);
+    NS_ENSURE_SUCCESS(rv, rv);
+
+#if !defined(HAVE_64BIT_BUILD)
+    // Ensure that temp tables are held in memory, not on disk, on 32 bit
+    // platforms.
+    rv = conn->ExecuteSimpleSQL("PRAGMA temp_store = MEMORY"_ns);
+    NS_ENSURE_SUCCESS(rv, rv);
+#endif
+
+    int32_t defaultPageSize;
+    rv = conn->GetDefaultPageSize(&defaultPageSize);
+    NS_ENSURE_SUCCESS(rv, rv);
+    rv = SetupDurability(conn, defaultPageSize);
+    NS_ENSURE_SUCCESS(rv, rv);
+
+    // We are going to update the database, so everything from now on should be
+    // in a transaction for performances.
+    mozStorageTransaction transaction(conn, false);
+    // XXX Handle the error, bug 1696133.
+    Unused << NS_WARN_IF(NS_FAILED(transaction.Start()));
+    rv = conn->ExecuteSimpleSQL(CREATE_MOZ_ICONS);
+    NS_ENSURE_SUCCESS(rv, rv);
+    rv = conn->ExecuteSimpleSQL(CREATE_IDX_MOZ_ICONS_ICONURLHASH);
+    NS_ENSURE_SUCCESS(rv, rv);
+    rv = conn->ExecuteSimpleSQL(CREATE_MOZ_PAGES_W_ICONS);
+    NS_ENSURE_SUCCESS(rv, rv);
+    rv = conn->ExecuteSimpleSQL(CREATE_IDX_MOZ_PAGES_W_ICONS_ICONURLHASH);
+    NS_ENSURE_SUCCESS(rv, rv);
+    rv = conn->ExecuteSimpleSQL(CREATE_MOZ_ICONS_TO_PAGES);
+    NS_ENSURE_SUCCESS(rv, rv);
+    rv = transaction.Commit();
+    NS_ENSURE_SUCCESS(rv, rv);
+
+    // The scope exit will take care of closing the connection.
+  }
+
+  rv = AttachDatabase(mMainConn, NS_ConvertUTF16toUTF8(iconsPath),
+                      "favicons"_ns);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  return NS_OK;
+}
+
+nsresult Database::BackupAndReplaceDatabaseFile(
+    nsCOMPtr<mozIStorageService>& aStorage, const nsString& aDbFilename,
+    bool aTryToClone, bool aReopenConnection) {
+  MOZ_ASSERT(NS_IsMainThread());
+
+  if (aDbFilename.Equals(DATABASE_FILENAME)) {
+    mDatabaseStatus = nsINavHistoryService::DATABASE_STATUS_CORRUPT;
+  } else {
+    // Due to OS file lockings, attached databases can't be cloned properly,
+    // otherwise trying to reattach them later would fail.
+    aTryToClone = false;
+  }
+
+  nsCOMPtr<nsIFile> profDir;
+  nsresult rv = NS_GetSpecialDirectory(NS_APP_USER_PROFILE_50_DIR,
+                                       getter_AddRefs(profDir));
+  NS_ENSURE_SUCCESS(rv, rv);
+  nsCOMPtr<nsIFile> databaseFile;
+  rv = profDir->Clone(getter_AddRefs(databaseFile));
+  NS_ENSURE_SUCCESS(rv, rv);
+  rv = databaseFile->Append(aDbFilename);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  // If we already failed in the last 24 hours avoid to create another corrupt
+  // file, since doing so, in some situation, could cause us to create a new
+  // corrupt file at every try to access any Places service.  That is bad
+  // because it would quickly fill the user's disk space without any notice.
+  nsCOMPtr<nsIFile> corruptFile;
+  rv = profDir->Clone(getter_AddRefs(corruptFile));
+  NS_ENSURE_SUCCESS(rv, rv);
+  nsString corruptFilename = getCorruptFilename(aDbFilename);
+  rv = corruptFile->Append(corruptFilename);
+  NS_ENSURE_SUCCESS(rv, rv);
+  if (!isRecentCorruptFile(corruptFile)) {
+    // Ensure we never create more than one corrupt file.
+    nsCOMPtr<nsIFile> corruptFile;
+    rv = profDir->Clone(getter_AddRefs(corruptFile));
+    NS_ENSURE_SUCCESS(rv, rv);
+    nsString corruptFilename = getCorruptFilename(aDbFilename);
+    rv = corruptFile->Append(corruptFilename);
+    NS_ENSURE_SUCCESS(rv, rv);
+    rv = corruptFile->Remove(false);
+    if (NS_FAILED(rv) && rv != NS_ERROR_FILE_NOT_FOUND) {
+      return rv;
+    }
+
+    nsCOMPtr<nsIFile> backup;
+    Unused << aStorage->BackupDatabaseFile(databaseFile, corruptFilename,
+                                           profDir, getter_AddRefs(backup));
+  }
+
+  // If anything fails from this point on, we have a stale connection or
+  // database file, and there's not much more we can do.
+  // The only thing we can try to do is to replace the database on the next
+  // startup, and report the problem through telemetry.
+  {
+    enum eCorruptDBReplaceStage : int8_t {
+      stage_closing = 0,
+      stage_removing,
+      stage_reopening,
+      stage_replaced,
+      stage_cloning,
+      stage_cloned
+    };
+    eCorruptDBReplaceStage stage = stage_closing;
+    auto guard = MakeScopeExit([&]() {
+      if (stage != stage_replaced) {
+        // Reaching this point means the database is corrupt and we failed to
+        // replace it.  For this session part of the application related to
+        // bookmarks and history will misbehave.  The frontend may show a
+        // "locked" notification to the user though.
+        // Set up a pref to try replacing the database at the next startup.
+        Preferences::SetString(PREF_FORCE_DATABASE_REPLACEMENT, aDbFilename);
+      }
+      // Report the corruption through telemetry.
+      Telemetry::Accumulate(
+          Telemetry::PLACES_DATABASE_CORRUPTION_HANDLING_STAGE,
+          static_cast<int8_t>(stage));
+    });
+
+    // Close database connection if open.
+    if (mMainConn) {
+      rv = mMainConn->SpinningSynchronousClose();
+      NS_ENSURE_SUCCESS(rv, rv);
+      mMainConn = nullptr;
+    }
+
+    // Remove the broken database.
+    stage = stage_removing;
+    rv = databaseFile->Remove(false);
+    if (NS_FAILED(rv) && rv != NS_ERROR_FILE_NOT_FOUND) {
+      return rv;
+    }
+
+    // Create a new database file and try to clone tables from the corrupt one.
+    bool cloned = false;
+    if (aTryToClone &&
+        Preferences::GetBool(PREF_DATABASE_CLONEONCORRUPTION, true)) {
+      stage = stage_cloning;
+      rv = TryToCloneTablesFromCorruptDatabase(aStorage, databaseFile);
+      if (NS_SUCCEEDED(rv)) {
+        // If we cloned successfully, we should not consider the database
+        // corrupt anymore, otherwise we could reimport default bookmarks.
+        mDatabaseStatus = nsINavHistoryService::DATABASE_STATUS_OK;
+        cloned = true;
+      }
+    }
+
+    if (aReopenConnection) {
+      // Use an unshared connection, it will consume more memory but avoid
+      // shared cache contentions across threads.
+      stage = stage_reopening;
+      rv = aStorage->OpenUnsharedDatabase(
+          databaseFile, mozIStorageService::CONNECTION_DEFAULT,
+          getter_AddRefs(mMainConn));
+      NS_ENSURE_SUCCESS(rv, rv);
+    }
+
+    stage = cloned ? stage_cloned : stage_replaced;
+  }
+
+  return NS_OK;
+}
+
+nsresult Database::TryToCloneTablesFromCorruptDatabase(
+    const nsCOMPtr<mozIStorageService>& aStorage,
+    const nsCOMPtr<nsIFile>& aDatabaseFile) {
+  MOZ_ASSERT(NS_IsMainThread());
+
+  nsAutoString filename;
+  nsresult rv = aDatabaseFile->GetLeafName(filename);
+
+  nsCOMPtr<nsIFile> corruptFile;
+  rv = aDatabaseFile->Clone(getter_AddRefs(corruptFile));
+  NS_ENSURE_SUCCESS(rv, rv);
+  rv = corruptFile->SetLeafName(getCorruptFilename(filename));
+  NS_ENSURE_SUCCESS(rv, rv);
+  nsAutoString path;
+  rv = corruptFile->GetPath(path);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  nsCOMPtr<nsIFile> recoverFile;
+  rv = aDatabaseFile->Clone(getter_AddRefs(recoverFile));
+  NS_ENSURE_SUCCESS(rv, rv);
+  rv = recoverFile->SetLeafName(getRecoverFilename(filename));
+  NS_ENSURE_SUCCESS(rv, rv);
+  // Ensure there's no previous recover file.
+  rv = recoverFile->Remove(false);
+  if (NS_FAILED(rv) && rv != NS_ERROR_FILE_NOT_FOUND) {
+    return rv;
+  }
+
+  nsCOMPtr<mozIStorageConnection> conn;
+  auto guard = MakeScopeExit([&]() {
+    if (conn) {
+      Unused << conn->Close();
+    }
+    Unused << recoverFile->Remove(false);
+  });
+
+  rv = aStorage->OpenUnsharedDatabase(recoverFile,
+                                      mozIStorageService::CONNECTION_DEFAULT,
+                                      getter_AddRefs(conn));
+  NS_ENSURE_SUCCESS(rv, rv);
+  rv = AttachDatabase(conn, NS_ConvertUTF16toUTF8(path), "corrupt"_ns);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  mozStorageTransaction transaction(conn, false);
+
+  // XXX Handle the error, bug 1696133.
+  Unused << NS_WARN_IF(NS_FAILED(transaction.Start()));
+
+  // Copy the schema version.
+  nsCOMPtr<mozIStorageStatement> stmt;
+  (void)conn->CreateStatement("PRAGMA corrupt.user_version"_ns,
+                              getter_AddRefs(stmt));
+  NS_ENSURE_TRUE(stmt, NS_ERROR_OUT_OF_MEMORY);
+  bool hasResult;
+  rv = stmt->ExecuteStep(&hasResult);
+  NS_ENSURE_SUCCESS(rv, rv);
+  int32_t schemaVersion = stmt->AsInt32(0);
+  rv = conn->SetSchemaVersion(schemaVersion);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  // Recreate the tables.
+  rv = conn->CreateStatement(
+      nsLiteralCString(
+          "SELECT name, sql FROM corrupt.sqlite_master "
+          "WHERE type = 'table' AND name BETWEEN 'moz_' AND 'moza'"),
+      getter_AddRefs(stmt));
+  NS_ENSURE_SUCCESS(rv, rv);
+  while (NS_SUCCEEDED(stmt->ExecuteStep(&hasResult)) && hasResult) {
+    nsAutoCString name;
+    rv = stmt->GetUTF8String(0, name);
+    NS_ENSURE_SUCCESS(rv, rv);
+    nsAutoCString query;
+    rv = stmt->GetUTF8String(1, query);
+    NS_ENSURE_SUCCESS(rv, rv);
+    rv = conn->ExecuteSimpleSQL(query);
+    NS_ENSURE_SUCCESS(rv, rv);
+    // Copy the table contents.
+    rv = conn->ExecuteSimpleSQL("INSERT INTO main."_ns + name +
+                                " SELECT * FROM corrupt."_ns + name);
+    if (NS_FAILED(rv)) {
+      rv = conn->ExecuteSimpleSQL("INSERT INTO main."_ns + name +
+                                  " SELECT * FROM corrupt."_ns + name +
+                                  " ORDER BY rowid DESC"_ns);
+    }
+    NS_ENSURE_SUCCESS(rv, rv);
+  }
+
+  // Recreate the indices.  Doing this after data addition is faster.
+  rv = conn->CreateStatement(
+      nsLiteralCString(
+          "SELECT sql FROM corrupt.sqlite_master "
+          "WHERE type <> 'table' AND name BETWEEN 'moz_' AND 'moza'"),
+      getter_AddRefs(stmt));
+  NS_ENSURE_SUCCESS(rv, rv);
+  hasResult = false;
+  while (NS_SUCCEEDED(stmt->ExecuteStep(&hasResult)) && hasResult) {
+    nsAutoCString query;
+    rv = stmt->GetUTF8String(0, query);
+    NS_ENSURE_SUCCESS(rv, rv);
+    rv = conn->ExecuteSimpleSQL(query);
+    NS_ENSURE_SUCCESS(rv, rv);
+  }
+  rv = stmt->Finalize();
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  rv = transaction.Commit();
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  Unused << conn->Close();
+  conn = nullptr;
+  rv = recoverFile->RenameTo(nullptr, filename);
+  NS_ENSURE_SUCCESS(rv, rv);
+  Unused << corruptFile->Remove(false);
+
+  guard.release();
+  return NS_OK;
+}
+
+nsresult Database::SetupDatabaseConnection(
+    nsCOMPtr<mozIStorageService>& aStorage) {
+  MOZ_ASSERT(NS_IsMainThread());
+
+  // Using immediate transactions allows the main connection to retry writes
+  // that fail with `SQLITE_BUSY` because a cloned connection has locked the
+  // database for writing.
+  nsresult rv = mMainConn->SetDefaultTransactionType(
+      mozIStorageConnection::TRANSACTION_IMMEDIATE);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  // WARNING: any statement executed before setting the journal mode must be
+  // finalized, since SQLite doesn't allow changing the journal mode if there
+  // is any outstanding statement.
+
+  {
+    // Get the page size.  This may be different than the default if the
+    // database file already existed with a different page size.
+    nsCOMPtr<mozIStorageStatement> statement;
+    rv = mMainConn->CreateStatement(
+        nsLiteralCString(MOZ_STORAGE_UNIQUIFY_QUERY_STR "PRAGMA page_size"),
+        getter_AddRefs(statement));
+    NS_ENSURE_SUCCESS(rv, rv);
+    bool hasResult = false;
+    rv = statement->ExecuteStep(&hasResult);
+    NS_ENSURE_TRUE(NS_SUCCEEDED(rv) && hasResult, NS_ERROR_FILE_CORRUPTED);
+    rv = statement->GetInt32(0, &mDBPageSize);
+    NS_ENSURE_TRUE(NS_SUCCEEDED(rv) && mDBPageSize > 0,
+                   NS_ERROR_FILE_CORRUPTED);
+  }
+
+#if !defined(HAVE_64BIT_BUILD)
+  // Ensure that temp tables are held in memory, not on disk, on 32 bit
+  // platforms.
+  rv = mMainConn->ExecuteSimpleSQL(nsLiteralCString(
+      MOZ_STORAGE_UNIQUIFY_QUERY_STR "PRAGMA temp_store = MEMORY"));
+  NS_ENSURE_SUCCESS(rv, rv);
+#endif
+
+  rv = SetupDurability(mMainConn, mDBPageSize);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  nsAutoCString busyTimeoutPragma("PRAGMA busy_timeout = ");
+  busyTimeoutPragma.AppendInt(DATABASE_BUSY_TIMEOUT_MS);
+  (void)mMainConn->ExecuteSimpleSQL(busyTimeoutPragma);
+
+  // Enable FOREIGN KEY support. This is a strict requirement.
+  rv = mMainConn->ExecuteSimpleSQL(nsLiteralCString(
+      MOZ_STORAGE_UNIQUIFY_QUERY_STR "PRAGMA foreign_keys = ON"));
+  NS_ENSURE_SUCCESS(rv, NS_ERROR_FILE_CORRUPTED);
+#ifdef DEBUG
+  {
+    // There are a few cases where setting foreign_keys doesn't work:
+    //  * in the middle of a multi-statement transaction
+    //  * if the SQLite library in use doesn't support them
+    // Since we need foreign_keys, let's at least assert in debug mode.
+    nsCOMPtr<mozIStorageStatement> stmt;
+    mMainConn->CreateStatement("PRAGMA foreign_keys"_ns, getter_AddRefs(stmt));
+    bool hasResult = false;
+    if (stmt && NS_SUCCEEDED(stmt->ExecuteStep(&hasResult)) && hasResult) {
+      int32_t fkState = stmt->AsInt32(0);
+      MOZ_ASSERT(fkState, "Foreign keys should be enabled");
+    }
+  }
+#endif
+
+  // Attach the favicons database to the main connection.
+  rv = EnsureFaviconsDatabaseAttached(aStorage);
+  if (NS_FAILED(rv)) {
+    // The favicons database may be corrupt. Try to replace and reattach it.
+    nsCOMPtr<nsIFile> iconsFile;
+    rv = NS_GetSpecialDirectory(NS_APP_USER_PROFILE_50_DIR,
+                                getter_AddRefs(iconsFile));
+    NS_ENSURE_SUCCESS(rv, rv);
+    rv = iconsFile->Append(DATABASE_FAVICONS_FILENAME);
+    NS_ENSURE_SUCCESS(rv, rv);
+    rv = iconsFile->Remove(false);
+    if (NS_FAILED(rv) && rv != NS_ERROR_FILE_NOT_FOUND) {
+      return rv;
+    }
+    rv = EnsureFaviconsDatabaseAttached(aStorage);
+    NS_ENSURE_SUCCESS(rv, rv);
+  }
+
+  // Create favicons temp entities.
+  rv = mMainConn->ExecuteSimpleSQL(CREATE_ICONS_AFTERINSERT_TRIGGER);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  // We use our functions during migration, so initialize them now.
+  rv = InitFunctions();
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  return NS_OK;
+}
+
+nsresult Database::InitSchema(bool* aDatabaseMigrated) {
+  MOZ_ASSERT(NS_IsMainThread());
+  *aDatabaseMigrated = false;
+
+  // Get the database schema version.
+  int32_t currentSchemaVersion;
+  nsresult rv = mMainConn->GetSchemaVersion(&currentSchemaVersion);
+  NS_ENSURE_SUCCESS(rv, rv);
+  bool databaseInitialized = currentSchemaVersion > 0;
+
+  if (databaseInitialized && currentSchemaVersion == DATABASE_SCHEMA_VERSION) {
+    // The database is up to date and ready to go.
+    return NS_OK;
+  }
+
+  auto guard = MakeScopeExit([&]() {
+    // These run at the end of the migration, out of the transaction,
+    // regardless of its success.
+    MigrateV52OriginFrecencies();
+  });
+
+  // We are going to update the database, so everything from now on should be in
+  // a transaction for performances.
+  mozStorageTransaction transaction(mMainConn, false);
+
+  // XXX Handle the error, bug 1696133.
+  Unused << NS_WARN_IF(NS_FAILED(transaction.Start()));
+
+  if (databaseInitialized) {
+    // Migration How-to:
+    //
+    // 1. increment PLACES_SCHEMA_VERSION.
+    // 2. implement a method that performs upgrade to your version from the
+    //    previous one.
+    //
+    // NOTE: The downgrade process is pretty much complicated by the fact old
+    //       versions cannot know what a new version is going to implement.
+    //       The only thing we will do for downgrades is setting back the schema
+    //       version, so that next upgrades will run again the migration step.
+
+    if (currentSchemaVersion < DATABASE_SCHEMA_VERSION) {
+      *aDatabaseMigrated = true;
+
+      if (currentSchemaVersion < 43) {
+        // These are versions older than Firefox 60 ESR that are not supported
+        // anymore.  In this case it's safer to just replace the database.
+        return NS_ERROR_FILE_CORRUPTED;
+      }
+
+      // Firefox 60 uses schema version 43. - This is an ESR.
+
+      if (currentSchemaVersion < 44) {
+        rv = MigrateV44Up();
+        NS_ENSURE_SUCCESS(rv, rv);
+      }
+
+      if (currentSchemaVersion < 45) {
+        rv = MigrateV45Up();
+        NS_ENSURE_SUCCESS(rv, rv);
+      }
+
+      if (currentSchemaVersion < 46) {
+        rv = MigrateV46Up();
+        NS_ENSURE_SUCCESS(rv, rv);
+      }
+
+      if (currentSchemaVersion < 47) {
+        rv = MigrateV47Up();
+        NS_ENSURE_SUCCESS(rv, rv);
+      }
+
+      // Firefox 61 uses schema version 47.
+
+      if (currentSchemaVersion < 48) {
+        rv = MigrateV48Up();
+        NS_ENSURE_SUCCESS(rv, rv);
+      }
+
+      if (currentSchemaVersion < 49) {
+        rv = MigrateV49Up();
+        NS_ENSURE_SUCCESS(rv, rv);
+      }
+
+      if (currentSchemaVersion < 50) {
+        rv = MigrateV50Up();
+        NS_ENSURE_SUCCESS(rv, rv);
+      }
+
+      if (currentSchemaVersion < 51) {
+        rv = MigrateV51Up();
+        NS_ENSURE_SUCCESS(rv, rv);
+      }
+
+      if (currentSchemaVersion < 52) {
+        rv = MigrateV52Up();
+        NS_ENSURE_SUCCESS(rv, rv);
+      }
+
+      // Firefox 62 uses schema version 52.
+      // Firefox 68 uses schema version 52. - This is an ESR.
+
+      if (currentSchemaVersion < 53) {
+        rv = MigrateV53Up();
+        NS_ENSURE_SUCCESS(rv, rv);
+      }
+
+      // Firefox 69 uses schema version 53
+      // Firefox 78 uses schema version 53 - This is an ESR.
+
+      if (currentSchemaVersion < 54) {
+        rv = MigrateV54Up();
+        NS_ENSURE_SUCCESS(rv, rv);
+      }
+
+      // Firefox 81 uses schema version 54
+
+      if (currentSchemaVersion < 55) {
+        rv = MigrateV55Up();
+        NS_ENSURE_SUCCESS(rv, rv);
+      }
+
+      if (currentSchemaVersion < 56) {
+        rv = MigrateV56Up();
+        NS_ENSURE_SUCCESS(rv, rv);
+      }
+
+      if (currentSchemaVersion < 57) {
+        rv = MigrateV57Up();
+        NS_ENSURE_SUCCESS(rv, rv);
+      }
+
+      // Firefox 91 uses schema version 57
+
+      // The schema 58 migration is no longer needed.
+
+      // Firefox 92 uses schema version 58
+
+      // The schema 59 migration is no longer needed.
+
+      // Firefox 94 uses schema version 59
+
+      if (currentSchemaVersion < 60) {
+        rv = MigrateV60Up();
+        NS_ENSURE_SUCCESS(rv, rv);
+      }
+
+      // Firefox 96 uses schema version 60
+
+      if (currentSchemaVersion < 61) {
+        rv = MigrateV61Up();
+        NS_ENSURE_SUCCESS(rv, rv);
+      }
+
+      // The schema 62 migration is no longer needed.
+
+      // Firefox 97 uses schema version 62
+
+      // The schema 63 migration is no longer needed.
+
+      // Firefox 98 uses schema version 63
+
+      // The schema 64 migration is no longer needed.
+
+      // Firefox 99 uses schema version 64
+
+      // The schema 65 migration is no longer needed.
+
+      // The schema 66 migration is no longer needed.
+
+      // Firefox 100 uses schema version 66
+
+      if (currentSchemaVersion < 67) {
+        rv = MigrateV67Up();
+        NS_ENSURE_SUCCESS(rv, rv);
+      }
+
+      // The schema 68 migration is no longer needed.
+
+      // Firefox 103 uses schema version 68
+
+      if (currentSchemaVersion < 69) {
+        rv = MigrateV69Up();
+        NS_ENSURE_SUCCESS(rv, rv);
+      }
+
+      // Firefox 104 uses schema version 69
+
+      if (currentSchemaVersion < 70) {
+        rv = MigrateV70Up();
+        NS_ENSURE_SUCCESS(rv, rv);
+      }
+
+      if (currentSchemaVersion < 71) {
+        rv = MigrateV71Up();
+        NS_ENSURE_SUCCESS(rv, rv);
+      }
+
+      // Firefox 110 uses schema version 71
+
+      // Schema Upgrades must add migration code here.
+      // >>> IMPORTANT! <<<
+      // NEVER MIX UP SYNC AND ASYNC EXECUTION IN MIGRATORS, YOU MAY LOCK THE
+      // CONNECTION AND CAUSE FURTHER STEPS TO FAIL.
+      // In case, set a bool and do the async work in the ScopeExit guard just
+      // before the migration steps.
+    }
+  } else {
+    // This is a new database, so we have to create all the tables and indices.
+
+    // moz_origins.
+    rv = mMainConn->ExecuteSimpleSQL(CREATE_MOZ_ORIGINS);
+    NS_ENSURE_SUCCESS(rv, rv);
+
+    // moz_places.
+    rv = mMainConn->ExecuteSimpleSQL(CREATE_MOZ_PLACES);
+    NS_ENSURE_SUCCESS(rv, rv);
+    rv = mMainConn->ExecuteSimpleSQL(CREATE_IDX_MOZ_PLACES_URL_HASH);
+    NS_ENSURE_SUCCESS(rv, rv);
+    rv = mMainConn->ExecuteSimpleSQL(CREATE_IDX_MOZ_PLACES_REVHOST);
+    NS_ENSURE_SUCCESS(rv, rv);
+    rv = mMainConn->ExecuteSimpleSQL(CREATE_IDX_MOZ_PLACES_VISITCOUNT);
+    NS_ENSURE_SUCCESS(rv, rv);
+    rv = mMainConn->ExecuteSimpleSQL(CREATE_IDX_MOZ_PLACES_FRECENCY);
+    NS_ENSURE_SUCCESS(rv, rv);
+    rv = mMainConn->ExecuteSimpleSQL(CREATE_IDX_MOZ_PLACES_LASTVISITDATE);
+    NS_ENSURE_SUCCESS(rv, rv);
+    rv = mMainConn->ExecuteSimpleSQL(CREATE_IDX_MOZ_PLACES_GUID);
+    NS_ENSURE_SUCCESS(rv, rv);
+    rv = mMainConn->ExecuteSimpleSQL(CREATE_IDX_MOZ_PLACES_ORIGIN_ID);
+    NS_ENSURE_SUCCESS(rv, rv);
+
+    // moz_historyvisits.
+    rv = mMainConn->ExecuteSimpleSQL(CREATE_MOZ_HISTORYVISITS);
+    NS_ENSURE_SUCCESS(rv, rv);
+    rv = mMainConn->ExecuteSimpleSQL(CREATE_IDX_MOZ_HISTORYVISITS_PLACEDATE);
+    NS_ENSURE_SUCCESS(rv, rv);
+    rv = mMainConn->ExecuteSimpleSQL(CREATE_IDX_MOZ_HISTORYVISITS_FROMVISIT);
+    NS_ENSURE_SUCCESS(rv, rv);
+    rv = mMainConn->ExecuteSimpleSQL(CREATE_IDX_MOZ_HISTORYVISITS_VISITDATE);
+    NS_ENSURE_SUCCESS(rv, rv);
+
+    // moz_inputhistory.
+    rv = mMainConn->ExecuteSimpleSQL(CREATE_MOZ_INPUTHISTORY);
+    NS_ENSURE_SUCCESS(rv, rv);
+
+    // moz_bookmarks.
+    rv = mMainConn->ExecuteSimpleSQL(CREATE_MOZ_BOOKMARKS);
+    NS_ENSURE_SUCCESS(rv, rv);
+    rv = mMainConn->ExecuteSimpleSQL(CREATE_MOZ_BOOKMARKS_DELETED);
+    NS_ENSURE_SUCCESS(rv, rv);
+    rv = mMainConn->ExecuteSimpleSQL(CREATE_IDX_MOZ_BOOKMARKS_PLACETYPE);
+    NS_ENSURE_SUCCESS(rv, rv);
+    rv = mMainConn->ExecuteSimpleSQL(CREATE_IDX_MOZ_BOOKMARKS_PARENTPOSITION);
+    NS_ENSURE_SUCCESS(rv, rv);
+    rv =
+        mMainConn->ExecuteSimpleSQL(CREATE_IDX_MOZ_BOOKMARKS_PLACELASTMODIFIED);
+    NS_ENSURE_SUCCESS(rv, rv);
+    rv = mMainConn->ExecuteSimpleSQL(CREATE_IDX_MOZ_BOOKMARKS_DATEADDED);
+    NS_ENSURE_SUCCESS(rv, rv);
+    rv = mMainConn->ExecuteSimpleSQL(CREATE_IDX_MOZ_BOOKMARKS_GUID);
+    NS_ENSURE_SUCCESS(rv, rv);
+
+    // moz_keywords.
+    rv = mMainConn->ExecuteSimpleSQL(CREATE_MOZ_KEYWORDS);
+    NS_ENSURE_SUCCESS(rv, rv);
+    rv = mMainConn->ExecuteSimpleSQL(CREATE_IDX_MOZ_KEYWORDS_PLACEPOSTDATA);
+    NS_ENSURE_SUCCESS(rv, rv);
+
+    // moz_anno_attributes.
+    rv = mMainConn->ExecuteSimpleSQL(CREATE_MOZ_ANNO_ATTRIBUTES);
+    NS_ENSURE_SUCCESS(rv, rv);
+
+    // moz_annos.
+    rv = mMainConn->ExecuteSimpleSQL(CREATE_MOZ_ANNOS);
+    NS_ENSURE_SUCCESS(rv, rv);
+    rv = mMainConn->ExecuteSimpleSQL(CREATE_IDX_MOZ_ANNOS_PLACEATTRIBUTE);
+    NS_ENSURE_SUCCESS(rv, rv);
+
+    // moz_items_annos.
+    rv = mMainConn->ExecuteSimpleSQL(CREATE_MOZ_ITEMS_ANNOS);
+    NS_ENSURE_SUCCESS(rv, rv);
+    rv = mMainConn->ExecuteSimpleSQL(CREATE_IDX_MOZ_ITEMSANNOS_PLACEATTRIBUTE);
+    NS_ENSURE_SUCCESS(rv, rv);
+
+    // moz_meta.
+    rv = mMainConn->ExecuteSimpleSQL(CREATE_MOZ_META);
+    NS_ENSURE_SUCCESS(rv, rv);
+
+    // moz_places_metadata
+    rv = mMainConn->ExecuteSimpleSQL(CREATE_MOZ_PLACES_METADATA);
+    NS_ENSURE_SUCCESS(rv, rv);
+    rv = mMainConn->ExecuteSimpleSQL(
+        CREATE_IDX_MOZ_PLACES_METADATA_PLACECREATED);
+    NS_ENSURE_SUCCESS(rv, rv);
+    rv = mMainConn->ExecuteSimpleSQL(CREATE_IDX_MOZ_PLACES_METADATA_REFERRER);
+    NS_ENSURE_SUCCESS(rv, rv);
+
+    // moz_places_metadata_search_queries
+    rv = mMainConn->ExecuteSimpleSQL(CREATE_MOZ_PLACES_METADATA_SEARCH_QUERIES);
+    NS_ENSURE_SUCCESS(rv, rv);
+
+    // moz_previews_tombstones
+    rv = mMainConn->ExecuteSimpleSQL(CREATE_MOZ_PREVIEWS_TOMBSTONES);
+    NS_ENSURE_SUCCESS(rv, rv);
+
+    // The bookmarks roots get initialized in CheckRoots().
+  }
+
+  // Set the schema version to the current one.
+  rv = mMainConn->SetSchemaVersion(DATABASE_SCHEMA_VERSION);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  rv = transaction.Commit();
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  // ANY FAILURE IN THIS METHOD WILL CAUSE US TO MARK THE DATABASE AS CORRUPT
+  // AND TRY TO REPLACE IT.
+  // DO NOT PUT HERE ANYTHING THAT IS NOT RELATED TO INITIALIZATION OR MODIFYING
+  // THE DISK DATABASE.
+
+  return NS_OK;
+}
+
+nsresult Database::CheckRoots() {
+  MOZ_ASSERT(NS_IsMainThread());
+
+  // If the database has just been created, skip straight to the part where
+  // we create the roots.
+  if (mDatabaseStatus == nsINavHistoryService::DATABASE_STATUS_CREATE) {
+    return EnsureBookmarkRoots(0, /* shouldReparentRoots */ false);
+  }
+
+  nsCOMPtr<mozIStorageStatement> stmt;
+  nsresult rv = mMainConn->CreateStatement(
+      nsLiteralCString("SELECT guid, id, position, parent FROM moz_bookmarks "
+                       "WHERE guid IN ( "
+                       "'" ROOT_GUID "', '" MENU_ROOT_GUID
+                       "', '" TOOLBAR_ROOT_GUID "', "
+                       "'" TAGS_ROOT_GUID "', '" UNFILED_ROOT_GUID
+                       "', '" MOBILE_ROOT_GUID "' )"),
+      getter_AddRefs(stmt));
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  bool hasResult;
+  nsAutoCString guid;
+  int32_t maxPosition = 0;
+  bool shouldReparentRoots = false;
+  while (NS_SUCCEEDED(stmt->ExecuteStep(&hasResult)) && hasResult) {
+    rv = stmt->GetUTF8String(0, guid);
+    NS_ENSURE_SUCCESS(rv, rv);
+
+    int64_t parentId = stmt->AsInt64(3);
+
+    if (guid.EqualsLiteral(ROOT_GUID)) {
+      mRootId = stmt->AsInt64(1);
+      shouldReparentRoots |= parentId != 0;
+    } else {
+      maxPosition = std::max(stmt->AsInt32(2), maxPosition);
+
+      if (guid.EqualsLiteral(MENU_ROOT_GUID)) {
+        mMenuRootId = stmt->AsInt64(1);
+      } else if (guid.EqualsLiteral(TOOLBAR_ROOT_GUID)) {
+        mToolbarRootId = stmt->AsInt64(1);
+      } else if (guid.EqualsLiteral(TAGS_ROOT_GUID)) {
+        mTagsRootId = stmt->AsInt64(1);
+      } else if (guid.EqualsLiteral(UNFILED_ROOT_GUID)) {
+        mUnfiledRootId = stmt->AsInt64(1);
+      } else if (guid.EqualsLiteral(MOBILE_ROOT_GUID)) {
+        mMobileRootId = stmt->AsInt64(1);
+      }
+      shouldReparentRoots |= parentId != mRootId;
+    }
+  }
+
+  rv = EnsureBookmarkRoots(maxPosition + 1, shouldReparentRoots);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  return NS_OK;
+}
+
+nsresult Database::EnsureBookmarkRoots(const int32_t startPosition,
+                                       bool shouldReparentRoots) {
+  MOZ_ASSERT(NS_IsMainThread());
+
+  nsresult rv;
+
+  if (mRootId < 1) {
+    // The first root's title is an empty string.
+    rv = CreateRoot(mMainConn, "places"_ns, "root________"_ns, ""_ns, 0,
+                    mRootId);
+
+    if (NS_FAILED(rv)) return rv;
+  }
+
+  int32_t position = startPosition;
+
+  // For the other roots, the UI doesn't rely on the value in the database, so
+  // just set it to something simple to make it easier for humans to read.
+  if (mMenuRootId < 1) {
+    rv = CreateRoot(mMainConn, "menu"_ns, "menu________"_ns, "menu"_ns,
+                    position, mMenuRootId);
+    if (NS_FAILED(rv)) return rv;
+    position++;
+  }
+
+  if (mToolbarRootId < 1) {
+    rv = CreateRoot(mMainConn, "toolbar"_ns, "toolbar_____"_ns, "toolbar"_ns,
+                    position, mToolbarRootId);
+    if (NS_FAILED(rv)) return rv;
+    position++;
+  }
+
+  if (mTagsRootId < 1) {
+    rv = CreateRoot(mMainConn, "tags"_ns, "tags________"_ns, "tags"_ns,
+                    position, mTagsRootId);
+    if (NS_FAILED(rv)) return rv;
+    position++;
+  }
+
+  if (mUnfiledRootId < 1) {
+    rv = CreateRoot(mMainConn, "unfiled"_ns, "unfiled_____"_ns, "unfiled"_ns,
+                    position, mUnfiledRootId);
+    if (NS_FAILED(rv)) return rv;
+    position++;
+  }
+
+  if (mMobileRootId < 1) {
+    int64_t mobileRootId = CreateMobileRoot();
+    if (mobileRootId <= 0) return NS_ERROR_FAILURE;
+    {
+      nsCOMPtr<mozIStorageStatement> mobileRootSyncStatusStmt;
+      rv = mMainConn->CreateStatement(
+          nsLiteralCString("UPDATE moz_bookmarks SET syncStatus = "
+                           ":sync_status WHERE id = :id"),
+          getter_AddRefs(mobileRootSyncStatusStmt));
+      if (NS_FAILED(rv)) return rv;
+
+      rv = mobileRootSyncStatusStmt->BindInt32ByName(
+          "sync_status"_ns, nsINavBookmarksService::SYNC_STATUS_NEW);
+      if (NS_FAILED(rv)) return rv;
+      rv = mobileRootSyncStatusStmt->BindInt64ByName("id"_ns, mobileRootId);
+      if (NS_FAILED(rv)) return rv;
+
+      rv = mobileRootSyncStatusStmt->Execute();
+      if (NS_FAILED(rv)) return rv;
+
+      mMobileRootId = mobileRootId;
+    }
+  }
+
+  if (!shouldReparentRoots) {
+    return NS_OK;
+  }
+
+  // At least one root had the wrong parent, so we need to ensure that
+  // all roots are parented correctly, fix their positions, and bump the
+  // Sync change counter.
+  rv = mMainConn->ExecuteSimpleSQL(nsLiteralCString(
+      "CREATE TEMP TRIGGER moz_ensure_bookmark_roots_trigger "
+      "AFTER UPDATE OF parent ON moz_bookmarks FOR EACH ROW "
+      "WHEN OLD.parent <> NEW.parent "
+      "BEGIN "
+      "UPDATE moz_bookmarks SET "
+      "syncChangeCounter = syncChangeCounter + 1 "
+      "WHERE id IN (OLD.parent, NEW.parent, NEW.id); "
+
+      "UPDATE moz_bookmarks SET "
+      "position = position - 1 "
+      "WHERE parent = OLD.parent AND position >= OLD.position; "
+
+      // Fix the positions of the root's old siblings. Since we've already
+      // moved the root, we need to exclude it from the subquery.
+      "UPDATE moz_bookmarks SET "
+      "position = IFNULL((SELECT MAX(position) + 1 FROM moz_bookmarks "
+      "WHERE parent = NEW.parent AND "
+      "id <> NEW.id), 0)"
+      "WHERE id = NEW.id; "
+      "END"));
+  if (NS_FAILED(rv)) return rv;
+  auto guard = MakeScopeExit([&]() {
+    Unused << mMainConn->ExecuteSimpleSQL(
+        "DROP TRIGGER moz_ensure_bookmark_roots_trigger"_ns);
+  });
+
+  nsCOMPtr<mozIStorageStatement> reparentStmt;
+  rv = mMainConn->CreateStatement(
+      nsLiteralCString(
+          "UPDATE moz_bookmarks SET "
+          "parent = CASE id WHEN :root_id THEN 0 ELSE :root_id END "
+          "WHERE id IN (:root_id, :menu_root_id, :toolbar_root_id, "
+          ":tags_root_id, "
+          ":unfiled_root_id, :mobile_root_id)"),
+      getter_AddRefs(reparentStmt));
+  if (NS_FAILED(rv)) return rv;
+
+  rv = reparentStmt->BindInt64ByName("root_id"_ns, mRootId);
+  if (NS_FAILED(rv)) return rv;
+  rv = reparentStmt->BindInt64ByName("menu_root_id"_ns, mMenuRootId);
+  if (NS_FAILED(rv)) return rv;
+  rv = reparentStmt->BindInt64ByName("toolbar_root_id"_ns, mToolbarRootId);
+  if (NS_FAILED(rv)) return rv;
+  rv = reparentStmt->BindInt64ByName("tags_root_id"_ns, mTagsRootId);
+  if (NS_FAILED(rv)) return rv;
+  rv = reparentStmt->BindInt64ByName("unfiled_root_id"_ns, mUnfiledRootId);
+  if (NS_FAILED(rv)) return rv;
+  rv = reparentStmt->BindInt64ByName("mobile_root_id"_ns, mMobileRootId);
+  if (NS_FAILED(rv)) return rv;
+
+  rv = reparentStmt->Execute();
+  if (NS_FAILED(rv)) return rv;
+
+  return NS_OK;
+}
+
+nsresult Database::InitFunctions() {
+  MOZ_ASSERT(NS_IsMainThread());
+
+  nsresult rv = GetUnreversedHostFunction::create(mMainConn);
+  NS_ENSURE_SUCCESS(rv, rv);
+  rv = MatchAutoCompleteFunction::create(mMainConn);
+  NS_ENSURE_SUCCESS(rv, rv);
+  rv = CalculateFrecencyFunction::create(mMainConn);
+  NS_ENSURE_SUCCESS(rv, rv);
+  rv = GenerateGUIDFunction::create(mMainConn);
+  NS_ENSURE_SUCCESS(rv, rv);
+  rv = IsValidGUIDFunction::create(mMainConn);
+  NS_ENSURE_SUCCESS(rv, rv);
+  rv = FixupURLFunction::create(mMainConn);
+  NS_ENSURE_SUCCESS(rv, rv);
+  rv = StoreLastInsertedIdFunction::create(mMainConn);
+  NS_ENSURE_SUCCESS(rv, rv);
+  rv = HashFunction::create(mMainConn);
+  NS_ENSURE_SUCCESS(rv, rv);
+  rv = GetQueryParamFunction::create(mMainConn);
+  NS_ENSURE_SUCCESS(rv, rv);
+  rv = GetPrefixFunction::create(mMainConn);
+  NS_ENSURE_SUCCESS(rv, rv);
+  rv = GetHostAndPortFunction::create(mMainConn);
+  NS_ENSURE_SUCCESS(rv, rv);
+  rv = StripPrefixAndUserinfoFunction::create(mMainConn);
+  NS_ENSURE_SUCCESS(rv, rv);
+  rv = IsFrecencyDecayingFunction::create(mMainConn);
+  NS_ENSURE_SUCCESS(rv, rv);
+  rv = NoteSyncChangeFunction::create(mMainConn);
+  NS_ENSURE_SUCCESS(rv, rv);
+  rv = InvalidateDaysOfHistoryFunction::create(mMainConn);
+  NS_ENSURE_SUCCESS(rv, rv);
+  rv = MD5HexFunction::create(mMainConn);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  return NS_OK;
+}
+
+nsresult Database::InitTempEntities() {
+  MOZ_ASSERT(NS_IsMainThread());
+
+  nsresult rv =
+      mMainConn->ExecuteSimpleSQL(CREATE_HISTORYVISITS_AFTERINSERT_TRIGGER);
+  NS_ENSURE_SUCCESS(rv, rv);
+  rv = mMainConn->ExecuteSimpleSQL(CREATE_HISTORYVISITS_AFTERDELETE_TRIGGER);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  // Add the triggers that update the moz_origins table as necessary.
+  rv = mMainConn->ExecuteSimpleSQL(CREATE_UPDATEORIGINSINSERT_TEMP);
+  NS_ENSURE_SUCCESS(rv, rv);
+  rv = mMainConn->ExecuteSimpleSQL(
+      CREATE_UPDATEORIGINSINSERT_AFTERDELETE_TRIGGER);
+  NS_ENSURE_SUCCESS(rv, rv);
+  rv = mMainConn->ExecuteSimpleSQL(CREATE_PLACES_AFTERINSERT_TRIGGER);
+  NS_ENSURE_SUCCESS(rv, rv);
+  rv = mMainConn->ExecuteSimpleSQL(CREATE_UPDATEORIGINSDELETE_TEMP);
+  NS_ENSURE_SUCCESS(rv, rv);
+  rv = mMainConn->ExecuteSimpleSQL(
+      CREATE_UPDATEORIGINSDELETE_AFTERDELETE_TRIGGER);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  if (Preferences::GetBool(PREF_PREVIEWS_ENABLED, false)) {
+    rv = mMainConn->ExecuteSimpleSQL(
+        CREATE_PLACES_AFTERDELETE_WPREVIEWS_TRIGGER);
+    NS_ENSURE_SUCCESS(rv, rv);
+  } else {
+    rv = mMainConn->ExecuteSimpleSQL(CREATE_PLACES_AFTERDELETE_TRIGGER);
+    NS_ENSURE_SUCCESS(rv, rv);
+  }
+
+  rv = mMainConn->ExecuteSimpleSQL(CREATE_UPDATEORIGINSUPDATE_TEMP);
+  NS_ENSURE_SUCCESS(rv, rv);
+  rv = mMainConn->ExecuteSimpleSQL(
+      CREATE_UPDATEORIGINSUPDATE_AFTERDELETE_TRIGGER);
+  NS_ENSURE_SUCCESS(rv, rv);
+  rv = mMainConn->ExecuteSimpleSQL(CREATE_PLACES_AFTERUPDATE_FRECENCY_TRIGGER);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  rv = mMainConn->ExecuteSimpleSQL(
+      CREATE_BOOKMARKS_FOREIGNCOUNT_AFTERDELETE_TRIGGER);
+  NS_ENSURE_SUCCESS(rv, rv);
+  rv = mMainConn->ExecuteSimpleSQL(
+      CREATE_BOOKMARKS_FOREIGNCOUNT_AFTERINSERT_TRIGGER);
+  NS_ENSURE_SUCCESS(rv, rv);
+  rv = mMainConn->ExecuteSimpleSQL(
+      CREATE_BOOKMARKS_FOREIGNCOUNT_AFTERUPDATE_TRIGGER);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  rv = mMainConn->ExecuteSimpleSQL(
+      CREATE_KEYWORDS_FOREIGNCOUNT_AFTERDELETE_TRIGGER);
+  NS_ENSURE_SUCCESS(rv, rv);
+  rv = mMainConn->ExecuteSimpleSQL(
+      CREATE_KEYWORDS_FOREIGNCOUNT_AFTERINSERT_TRIGGER);
+  NS_ENSURE_SUCCESS(rv, rv);
+  rv = mMainConn->ExecuteSimpleSQL(
+      CREATE_KEYWORDS_FOREIGNCOUNT_AFTERUPDATE_TRIGGER);
+  NS_ENSURE_SUCCESS(rv, rv);
+  rv =
+      mMainConn->ExecuteSimpleSQL(CREATE_BOOKMARKS_DELETED_AFTERINSERT_TRIGGER);
+  NS_ENSURE_SUCCESS(rv, rv);
+  rv =
+      mMainConn->ExecuteSimpleSQL(CREATE_BOOKMARKS_DELETED_AFTERDELETE_TRIGGER);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  rv = mMainConn->ExecuteSimpleSQL(CREATE_PLACES_METADATA_AFTERDELETE_TRIGGER);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  return NS_OK;
+}
+
+nsresult Database::MigrateV44Up() {
+  // We need to remove any non-builtin roots and their descendants.
+
+  // Install a temp trigger to clean up linked tables when the main
+  // bookmarks are deleted.
+  nsresult rv = mMainConn->ExecuteSimpleSQL(nsLiteralCString(
+      "CREATE TEMP TRIGGER moz_migrate_bookmarks_trigger "
+      "AFTER DELETE ON moz_bookmarks FOR EACH ROW "
+      "BEGIN "
+      // Insert tombstones.
+      "INSERT OR IGNORE INTO moz_bookmarks_deleted (guid, dateRemoved) "
+      "VALUES (OLD.guid, strftime('%s', 'now', 'localtime', 'utc') * 1000000); "
+      // Remove old annotations for the bookmarks.
+      "DELETE FROM moz_items_annos "
+      "WHERE item_id = OLD.id; "
+      // Decrease the foreign_count in moz_places.
+      "UPDATE moz_places "
+      "SET foreign_count = foreign_count - 1 "
+      "WHERE id = OLD.fk; "
+      "END "));
+  if (NS_FAILED(rv)) return rv;
+
+  // This trigger listens for moz_places deletes, and updates moz_annos and
+  // moz_keywords accordingly.
+  rv = mMainConn->ExecuteSimpleSQL(nsLiteralCString(
+      "CREATE TEMP TRIGGER moz_migrate_annos_trigger "
+      "AFTER UPDATE ON moz_places FOR EACH ROW "
+      // Only remove from moz_places if we don't have any remaining keywords
+      // pointing to this place, and it hasn't been visited. Note: orphan
+      // keywords are tidied up below.
+      "WHEN NEW.visit_count = 0 AND "
+      " NEW.foreign_count = (SELECT COUNT(*) FROM moz_keywords WHERE place_id "
+      "= NEW.id) "
+      "BEGIN "
+      // No more references to the place, so we can delete the place itself.
+      "DELETE FROM moz_places "
+      "WHERE id = NEW.id; "
+      // Delete annotations relating to the place.
+      "DELETE FROM moz_annos "
+      "WHERE place_id = NEW.id; "
+      // Delete keywords relating to the place.
+      "DELETE FROM moz_keywords "
+      "WHERE place_id = NEW.id; "
+      "END "));
+  if (NS_FAILED(rv)) return rv;
+
+  // Listens to moz_keyword deletions, to ensure moz_places gets the
+  // foreign_count updated corrrectly.
+  rv = mMainConn->ExecuteSimpleSQL(
+      nsLiteralCString("CREATE TEMP TRIGGER moz_migrate_keyword_trigger "
+                       "AFTER DELETE ON moz_keywords FOR EACH ROW "
+                       "BEGIN "
+                       // If we remove a keyword, then reduce the foreign_count.
+                       "UPDATE moz_places "
+                       "SET foreign_count = foreign_count - 1 "
+                       "WHERE id = OLD.place_id; "
+                       "END "));
+  if (NS_FAILED(rv)) return rv;
+
+  // First of all, find the non-builtin roots.
+  nsCOMPtr<mozIStorageStatement> deleteStmt;
+  rv = mMainConn->CreateStatement(
+      nsLiteralCString("WITH RECURSIVE "
+                       "itemsToRemove(id, guid) AS ( "
+                       "SELECT b.id, b.guid FROM moz_bookmarks b "
+                       "JOIN moz_bookmarks p ON b.parent = p.id "
+                       "WHERE p.guid = 'root________' AND "
+                       "b.guid NOT IN ('menu________', 'toolbar_____', "
+                       "'tags________', 'unfiled_____', 'mobile______') "
+                       "UNION ALL "
+                       "SELECT b.id, b.guid FROM moz_bookmarks b "
+                       "JOIN itemsToRemove d ON d.id = b.parent "
+                       "WHERE b.guid NOT IN ('menu________', 'toolbar_____', "
+                       "'tags________', 'unfiled_____', 'mobile______') "
+                       ") "
+                       "DELETE FROM moz_bookmarks "
+                       "WHERE id IN (SELECT id FROM itemsToRemove) "),
+      getter_AddRefs(deleteStmt));
+  if (NS_FAILED(rv)) return rv;
+
+  rv = deleteStmt->Execute();
+  if (NS_FAILED(rv)) return rv;
+
+  // Before we remove the triggers, check for keywords attached to places which
+  // no longer have a bookmark to them. We do this before removing the triggers,
+  // so that we can make use of the keyword trigger to update the counts in
+  // moz_places.
+  rv = mMainConn->ExecuteSimpleSQL(
+      nsLiteralCString("DELETE FROM moz_keywords WHERE place_id IN ( "
+                       "SELECT h.id FROM moz_keywords k "
+                       "JOIN moz_places h ON h.id = k.place_id "
+                       "GROUP BY place_id HAVING h.foreign_count = count(*) "
+                       ")"));
+  if (NS_FAILED(rv)) return rv;
+
+  // Now remove the temp triggers.
+  rv = mMainConn->ExecuteSimpleSQL(
+      "DROP TRIGGER moz_migrate_bookmarks_trigger "_ns);
+  if (NS_FAILED(rv)) return rv;
+  rv =
+      mMainConn->ExecuteSimpleSQL("DROP TRIGGER moz_migrate_annos_trigger "_ns);
+  if (NS_FAILED(rv)) return rv;
+  rv = mMainConn->ExecuteSimpleSQL(
+      "DROP TRIGGER moz_migrate_keyword_trigger "_ns);
+  if (NS_FAILED(rv)) return rv;
+
+  // Cleanup any orphan annotation attributes.
+  rv = mMainConn->ExecuteSimpleSQL(
+      nsLiteralCString("DELETE FROM moz_anno_attributes WHERE id IN ( "
+                       "SELECT id FROM moz_anno_attributes n "
+                       "EXCEPT "
+                       "SELECT DISTINCT anno_attribute_id FROM moz_annos "
+                       "EXCEPT "
+                       "SELECT DISTINCT anno_attribute_id FROM moz_items_annos "
+                       ")"));
+  if (NS_FAILED(rv)) return rv;
+
+  return NS_OK;
+}
+
+nsresult Database::MigrateV45Up() {
+  nsCOMPtr<mozIStorageStatement> metaTableStmt;
+  nsresult rv = mMainConn->CreateStatement("SELECT 1 FROM moz_meta"_ns,
+                                           getter_AddRefs(metaTableStmt));
+  if (NS_FAILED(rv)) {
+    rv = mMainConn->ExecuteSimpleSQL(CREATE_MOZ_META);
+    NS_ENSURE_SUCCESS(rv, rv);
+  }
+  return NS_OK;
+}
+
+nsresult Database::MigrateV46Up() {
+  // Convert the existing queries. For simplicity we assume the user didn't
+  // edit these queries, and just do a 1:1 conversion.
+  nsresult rv = mMainConn->ExecuteSimpleSQL(nsLiteralCString(
+      "UPDATE moz_places "
+      "SET url = IFNULL('place:tag=' || ( "
+      "SELECT title FROM moz_bookmarks "
+      "WHERE id = CAST(get_query_param(substr(url, 7), 'folder') AS INT) "
+      "), url) "
+      "WHERE url_hash BETWEEN hash('place', 'prefix_lo') AND "
+      "hash('place', 'prefix_hi') "
+      "AND url LIKE '%type=7%' "
+      "AND EXISTS(SELECT 1 FROM moz_bookmarks "
+      "WHERE id = CAST(get_query_param(substr(url, 7), 'folder') AS INT)) "));
+
+  // Recalculate hashes for all tag queries.
+  rv = mMainConn->ExecuteSimpleSQL(
+      nsLiteralCString("UPDATE moz_places SET url_hash = hash(url) "
+                       "WHERE url_hash BETWEEN hash('place', 'prefix_lo') AND "
+                       "hash('place', 'prefix_hi') "
+                       "AND url LIKE '%tag=%' "));
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  // Update Sync fields for all tag queries.
+  rv = mMainConn->ExecuteSimpleSQL(nsLiteralCString(
+      "UPDATE moz_bookmarks SET syncChangeCounter = syncChangeCounter + 1 "
+      "WHERE fk IN ( "
+      "SELECT id FROM moz_places "
+      "WHERE url_hash BETWEEN hash('place', 'prefix_lo') AND "
+      "hash('place', 'prefix_hi') "
+      "AND url LIKE '%tag=%' "
+      ") "));
+  NS_ENSURE_SUCCESS(rv, rv);
+  return NS_OK;
+}
+
+nsresult Database::MigrateV47Up() {
+  // v46 may have mistakenly set some url to NULL, we must fix those.
+  // Since the original url was an invalid query, we replace NULLs with an
+  // empty query.
+  nsresult rv = mMainConn->ExecuteSimpleSQL(
+      nsLiteralCString("UPDATE moz_places "
+                       "SET url = 'place:excludeItems=1', url_hash = "
+                       "hash('place:excludeItems=1') "
+                       "WHERE url ISNULL "));
+  NS_ENSURE_SUCCESS(rv, rv);
+  // Update Sync fields for these queries.
+  rv = mMainConn->ExecuteSimpleSQL(nsLiteralCString(
+      "UPDATE moz_bookmarks SET syncChangeCounter = syncChangeCounter + 1 "
+      "WHERE fk IN ( "
+      "SELECT id FROM moz_places "
+      "WHERE url_hash = hash('place:excludeItems=1') "
+      "AND url = 'place:excludeItems=1' "
+      ") "));
+  NS_ENSURE_SUCCESS(rv, rv);
+  return NS_OK;
+}
+
+nsresult Database::MigrateV48Up() {
+  // Create and populate moz_origins.
+  nsCOMPtr<mozIStorageStatement> stmt;
+  nsresult rv = mMainConn->CreateStatement("SELECT * FROM moz_origins; "_ns,
+                                           getter_AddRefs(stmt));
+  if (NS_FAILED(rv)) {
+    rv = mMainConn->ExecuteSimpleSQL(CREATE_MOZ_ORIGINS);
+    NS_ENSURE_SUCCESS(rv, rv);
+  }
+  rv = mMainConn->ExecuteSimpleSQL(nsLiteralCString(
+      "INSERT OR IGNORE INTO moz_origins (prefix, host, frecency) "
+      "SELECT get_prefix(url), get_host_and_port(url), -1 "
+      "FROM moz_places; "));
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  // Add and populate moz_places.origin_id.
+  rv = mMainConn->CreateStatement("SELECT origin_id FROM moz_places; "_ns,
+                                  getter_AddRefs(stmt));
+  if (NS_FAILED(rv)) {
+    rv = mMainConn->ExecuteSimpleSQL(nsLiteralCString(
+        "ALTER TABLE moz_places "
+        "ADD COLUMN origin_id INTEGER REFERENCES moz_origins(id); "));
+    NS_ENSURE_SUCCESS(rv, rv);
+  }
+  rv = mMainConn->ExecuteSimpleSQL(CREATE_IDX_MOZ_PLACES_ORIGIN_ID);
+  NS_ENSURE_SUCCESS(rv, rv);
+  rv = mMainConn->ExecuteSimpleSQL(nsLiteralCString(
+      "UPDATE moz_places "
+      "SET origin_id = ( "
+      "SELECT id FROM moz_origins "
+      "WHERE prefix = get_prefix(url) AND host = get_host_and_port(url) "
+      "); "));
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  // From this point on, nobody should use moz_hosts again.  Empty it so that we
+  // don't leak the user's history, but don't remove it yet so that the user can
+  // downgrade.
+  // This can fail, if moz_hosts doesn't exist anymore, that is what happens in
+  // case of downgrade+upgrade.
+  Unused << mMainConn->ExecuteSimpleSQL("DELETE FROM moz_hosts; "_ns);
+
+  return NS_OK;
+}
+
+nsresult Database::MigrateV49Up() {
+  // These hidden preferences were added along with the v48 migration as part of
+  // the frecency stats implementation but are now replaced with entries in the
+  // moz_meta table.
+  Unused << Preferences::ClearUser("places.frecency.stats.count");
+  Unused << Preferences::ClearUser("places.frecency.stats.sum");
+  Unused << Preferences::ClearUser("places.frecency.stats.sumOfSquares");
+  return NS_OK;
+}
+
+nsresult Database::MigrateV50Up() {
+  // Convert the existing queries. We don't have REGEX available, so the
+  // simplest thing to do is to pull the urls out, and process them manually.
+  nsCOMPtr<mozIStorageStatement> stmt;
+  nsresult rv = mMainConn->CreateStatement(
+      nsLiteralCString("SELECT id, url FROM moz_places "
+                       "WHERE url_hash BETWEEN hash('place', 'prefix_lo') AND "
+                       "hash('place', 'prefix_hi') "
+                       "AND url LIKE '%folder=%' "),
+      getter_AddRefs(stmt));
+  if (NS_FAILED(rv)) return rv;
+
+  AutoTArray<std::pair<int64_t, nsCString>, 32> placeURLs;
+
+  bool hasMore = false;
+  nsCString url;
+  while (NS_SUCCEEDED(stmt->ExecuteStep(&hasMore)) && hasMore) {
+    int64_t placeId;
+    rv = stmt->GetInt64(0, &placeId);
+    if (NS_FAILED(rv)) return rv;
+    rv = stmt->GetUTF8String(1, url);
+    if (NS_FAILED(rv)) return rv;
+
+    // XXX(Bug 1631371) Check if this should use a fallible operation as it
+    // pretended earlier.
+    placeURLs.AppendElement(std::make_pair(placeId, url));
+  }
+
+  if (placeURLs.IsEmpty()) {
+    return NS_OK;
+  }
+
+  int64_t placeId;
+  for (uint32_t i = 0; i < placeURLs.Length(); ++i) {
+    placeId = placeURLs[i].first;
+    url = placeURLs[i].second;
+
+    rv = ConvertOldStyleQuery(url);
+    // Something bad happened, and we can't convert it, so just continue.
+    if (NS_WARN_IF(NS_FAILED(rv))) {
+      continue;
+    }
+
+    nsCOMPtr<mozIStorageStatement> updateStmt;
+    rv = mMainConn->CreateStatement(
+        nsLiteralCString("UPDATE moz_places "
+                         "SET url = :url, url_hash = hash(:url) "
+                         "WHERE id = :placeId "),
+        getter_AddRefs(updateStmt));
+    if (NS_FAILED(rv)) return rv;
+
+    rv = URIBinder::Bind(updateStmt, "url"_ns, url);
+    if (NS_FAILED(rv)) return rv;
+    rv = updateStmt->BindInt64ByName("placeId"_ns, placeId);
+    if (NS_FAILED(rv)) return rv;
+
+    rv = updateStmt->Execute();
+    if (NS_FAILED(rv)) return rv;
+
+    // Update Sync fields for these queries.
+    nsCOMPtr<mozIStorageStatement> syncStmt;
+    rv = mMainConn->CreateStatement(
+        nsLiteralCString("UPDATE moz_bookmarks SET syncChangeCounter = "
+                         "syncChangeCounter + 1 "
+                         "WHERE fk = :placeId "),
+        getter_AddRefs(syncStmt));
+    if (NS_FAILED(rv)) return rv;
+
+    rv = syncStmt->BindInt64ByName("placeId"_ns, placeId);
+    if (NS_FAILED(rv)) return rv;
+
+    rv = syncStmt->Execute();
+    if (NS_FAILED(rv)) return rv;
+  }
+
+  return NS_OK;
+}
+
+nsresult Database::MigrateV51Up() {
+  nsCOMPtr<mozIStorageStatement> stmt;
+  nsresult rv = mMainConn->CreateStatement(
+      nsLiteralCString("SELECT b.guid FROM moz_anno_attributes n "
+                       "JOIN moz_items_annos a ON n.id = a.anno_attribute_id "
+                       "JOIN moz_bookmarks b ON a.item_id = b.id "
+                       "WHERE n.name = :anno_name ORDER BY a.content DESC"),
+      getter_AddRefs(stmt));
+  if (NS_FAILED(rv)) {
+    MOZ_ASSERT(false,
+               "Should succeed unless item annotations table has been removed");
+    return NS_OK;
+  };
+
+  rv = stmt->BindUTF8StringByName("anno_name"_ns, LAST_USED_ANNO);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  JSONStringWriteFunc<nsAutoCString> json;
+  JSONWriter jw{json};
+  jw.StartArrayProperty(nullptr, JSONWriter::SingleLineStyle);
+
+  bool hasAtLeastOne = false;
+  bool hasMore = false;
+  uint32_t length;
+  while (NS_SUCCEEDED(stmt->ExecuteStep(&hasMore)) && hasMore) {
+    hasAtLeastOne = true;
+    const char* stmtString = stmt->AsSharedUTF8String(0, &length);
+    jw.StringElement(Span<const char>(stmtString, length));
+  }
+  jw.EndArray();
+
+  // If we don't have any, just abort early and save the extra work.
+  if (!hasAtLeastOne) {
+    return NS_OK;
+  }
+
+  rv = mMainConn->CreateStatement(
+      nsLiteralCString("INSERT OR REPLACE INTO moz_meta "
+                       "VALUES (:key, :value) "),
+      getter_AddRefs(stmt));
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  rv = stmt->BindUTF8StringByName("key"_ns, LAST_USED_FOLDERS_META_KEY);
+  NS_ENSURE_SUCCESS(rv, rv);
+  rv = stmt->BindUTF8StringByName("value"_ns, json.StringCRef());
+  NS_ENSURE_SUCCESS(rv, rv);
+  rv = stmt->Execute();
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  // Clean up the now redundant annotations.
+  rv = mMainConn->CreateStatement(
+      nsLiteralCString(
+          "DELETE FROM moz_items_annos WHERE anno_attribute_id = "
+          "(SELECT id FROM moz_anno_attributes WHERE name = :anno_name) "),
+      getter_AddRefs(stmt));
+  NS_ENSURE_SUCCESS(rv, rv);
+  rv = stmt->BindUTF8StringByName("anno_name"_ns, LAST_USED_ANNO);
+  NS_ENSURE_SUCCESS(rv, rv);
+  rv = stmt->Execute();
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  rv = mMainConn->CreateStatement(
+      nsLiteralCString(
+          "DELETE FROM moz_anno_attributes WHERE name = :anno_name "),
+      getter_AddRefs(stmt));
+  NS_ENSURE_SUCCESS(rv, rv);
+  rv = stmt->BindUTF8StringByName("anno_name"_ns, LAST_USED_ANNO);
+  NS_ENSURE_SUCCESS(rv, rv);
+  rv = stmt->Execute();
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  return NS_OK;
+}
+
+namespace {
+
+class MigrateV52OriginFrecenciesRunnable final : public Runnable {
+ public:
+  NS_DECL_NSIRUNNABLE
+  explicit MigrateV52OriginFrecenciesRunnable(mozIStorageConnection* aDBConn);
+
+ private:
+  nsCOMPtr<mozIStorageConnection> mDBConn;
+};
+
+MigrateV52OriginFrecenciesRunnable::MigrateV52OriginFrecenciesRunnable(
+    mozIStorageConnection* aDBConn)
+    : Runnable("places::MigrateV52OriginFrecenciesRunnable"),
+      mDBConn(aDBConn) {}
+
+NS_IMETHODIMP
+MigrateV52OriginFrecenciesRunnable::Run() {
+  if (NS_IsMainThread()) {
+    // Migration done.  Clear the pref.
+    Unused << Preferences::ClearUser(PREF_MIGRATE_V52_ORIGIN_FRECENCIES);
+
+    // Now that frecencies have been migrated, recalculate the origin frecency
+    // stats.
+    nsNavHistory* navHistory = nsNavHistory::GetHistoryService();
+    NS_ENSURE_STATE(navHistory);
+    nsresult rv = navHistory->RecalculateOriginFrecencyStats(nullptr);
+    NS_ENSURE_SUCCESS(rv, rv);
+
+    return NS_OK;
+  }
+
+  // We do the work in chunks, or the wal journal may grow too much.
+  nsresult rv = mDBConn->ExecuteSimpleSQL(nsLiteralCString(
+      "UPDATE moz_origins "
+      "SET frecency = ( "
+      "SELECT CAST(TOTAL(frecency) AS INTEGER) "
+      "FROM moz_places "
+      "WHERE frecency > 0 AND moz_places.origin_id = moz_origins.id "
+      ") "
+      "WHERE id IN ( "
+      "SELECT id "
+      "FROM moz_origins "
+      "WHERE frecency < 0 "
+      "LIMIT 400 "
+      ") "));
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  nsCOMPtr<mozIStorageStatement> selectStmt;
+  rv = mDBConn->CreateStatement(nsLiteralCString("SELECT 1 "
+                                                 "FROM moz_origins "
+                                                 "WHERE frecency < 0 "
+                                                 "LIMIT 1 "),
+                                getter_AddRefs(selectStmt));
+  NS_ENSURE_SUCCESS(rv, rv);
+  bool hasResult = false;
+  rv = selectStmt->ExecuteStep(&hasResult);
+  NS_ENSURE_SUCCESS(rv, rv);
+  if (hasResult) {
+    // There are more results to handle. Re-dispatch to the same thread for the
+    // next chunk.
+    return NS_DispatchToCurrentThread(this);
+  }
+
+  // Re-dispatch to the main-thread to flip the migration pref.
+  return NS_DispatchToMainThread(this);
+}
+
+}  // namespace
+
+void Database::MigrateV52OriginFrecencies() {
+  MOZ_ASSERT(NS_IsMainThread());
+
+  if (!Preferences::GetBool(PREF_MIGRATE_V52_ORIGIN_FRECENCIES)) {
+    // The migration has already been completed.
+    return;
+  }
+
+  RefPtr<MigrateV52OriginFrecenciesRunnable> runnable(
+      new MigrateV52OriginFrecenciesRunnable(mMainConn));
+  nsCOMPtr<nsIEventTarget> target(do_GetInterface(mMainConn));
+  MOZ_ASSERT(target);
+  if (target) {
+    Unused << target->Dispatch(runnable, NS_DISPATCH_NORMAL);
+  }
+}
+
+nsresult Database::MigrateV52Up() {
+  // Before this migration, moz_origin.frecency is the max frecency of all
+  // places with the origin.  After this migration, it's the sum of frecencies
+  // of all places with the origin.
+  //
+  // Setting this pref will cause InitSchema to begin async migration, via
+  // MigrateV52OriginFrecencies.  When that migration is done, origin frecency
+  // stats are recalculated (see MigrateV52OriginFrecenciesRunnable::Run).
+  Unused << Preferences::SetBool(PREF_MIGRATE_V52_ORIGIN_FRECENCIES, true);
+
+  // Set all origin frecencies to -1 so that MigrateV52OriginFrecenciesRunnable
+  // will migrate them.
+  nsresult rv =
+      mMainConn->ExecuteSimpleSQL("UPDATE moz_origins SET frecency = -1 "_ns);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  // This migration also renames these moz_meta keys that keep track of frecency
+  // stats.  (That happens when stats are recalculated.)  Delete the old ones.
+  rv =
+      mMainConn->ExecuteSimpleSQL(nsLiteralCString("DELETE FROM moz_meta "
+                                                   "WHERE key IN ( "
+                                                   "'frecency_count', "
+                                                   "'frecency_sum', "
+                                                   "'frecency_sum_of_squares' "
+                                                   ") "));
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  return NS_OK;
+}
+
+nsresult Database::MigrateV53Up() {
+  nsCOMPtr<mozIStorageStatement> stmt;
+  nsresult rv = mMainConn->CreateStatement("SELECT 1 FROM moz_items_annos"_ns,
+                                           getter_AddRefs(stmt));
+  if (NS_FAILED(rv)) {
+    // Likely we removed the table.
+    return NS_OK;
+  }
+
+  // Remove all item annotations but SYNC_PARENT_ANNO.
+  rv = mMainConn->CreateStatement(
+      nsLiteralCString(
+          "DELETE FROM moz_items_annos "
+          "WHERE anno_attribute_id NOT IN ( "
+          "  SELECT id FROM moz_anno_attributes WHERE name = :anno_name "
+          ") "),
+      getter_AddRefs(stmt));
+  NS_ENSURE_SUCCESS(rv, rv);
+  rv = stmt->BindUTF8StringByName("anno_name"_ns,
+                                  nsLiteralCString(SYNC_PARENT_ANNO));
+  NS_ENSURE_SUCCESS(rv, rv);
+  rv = stmt->Execute();
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  rv = mMainConn->ExecuteSimpleSQL(nsLiteralCString(
+      "DELETE FROM moz_anno_attributes WHERE id IN ( "
+      "  SELECT id FROM moz_anno_attributes "
+      "  EXCEPT "
+      "  SELECT DISTINCT anno_attribute_id FROM moz_annos "
+      "  EXCEPT "
+      "  SELECT DISTINCT anno_attribute_id FROM moz_items_annos "
+      ")"));
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  return NS_OK;
+}
+
+nsresult Database::MigrateV54Up() {
+  // Add an expiration column to moz_icons_to_pages.
+  nsCOMPtr<mozIStorageStatement> stmt;
+  nsresult rv = mMainConn->CreateStatement(
+      "SELECT expire_ms FROM moz_icons_to_pages"_ns, getter_AddRefs(stmt));
+  if (NS_FAILED(rv)) {
+    rv = mMainConn->ExecuteSimpleSQL(
+        "ALTER TABLE moz_icons_to_pages "
+        "ADD COLUMN expire_ms INTEGER NOT NULL DEFAULT 0 "_ns);
+    NS_ENSURE_SUCCESS(rv, rv);
+  }
+
+  // Set all the zero-ed entries as expired today, they won't be removed until
+  // the next related page load.
+  rv = mMainConn->ExecuteSimpleSQL(
+      "UPDATE moz_icons_to_pages "
+      "SET expire_ms = strftime('%s','now','localtime','start "
+      "of day','utc') * 1000 "
+      "WHERE expire_ms = 0 "_ns);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  return NS_OK;
+}
+
+nsresult Database::MigrateV55Up() {
+  // Add places metadata tables.
+  nsCOMPtr<mozIStorageStatement> stmt;
+  nsresult rv = mMainConn->CreateStatement(
+      "SELECT id FROM moz_places_metadata"_ns, getter_AddRefs(stmt));
+  if (NS_FAILED(rv)) {
+    // Create the tables.
+    rv = mMainConn->ExecuteSimpleSQL(CREATE_MOZ_PLACES_METADATA);
+    NS_ENSURE_SUCCESS(rv, rv);
+    // moz_places_metadata_search_queries.
+    rv = mMainConn->ExecuteSimpleSQL(CREATE_MOZ_PLACES_METADATA_SEARCH_QUERIES);
+    NS_ENSURE_SUCCESS(rv, rv);
+  }
+
+  return NS_OK;
+}
+
+nsresult Database::MigrateV56Up() {
+  // Add places metadata (place_id, created_at) index.
+  return mMainConn->ExecuteSimpleSQL(
+      CREATE_IDX_MOZ_PLACES_METADATA_PLACECREATED);
+}
+
+nsresult Database::MigrateV57Up() {
+  // Add the scrolling columns to the metadata.
+  nsCOMPtr<mozIStorageStatement> stmt;
+  nsresult rv = mMainConn->CreateStatement(
+      "SELECT scrolling_time FROM moz_places_metadata"_ns,
+      getter_AddRefs(stmt));
+  if (NS_FAILED(rv)) {
+    rv = mMainConn->ExecuteSimpleSQL(
+        "ALTER TABLE moz_places_metadata "
+        "ADD COLUMN scrolling_time INTEGER NOT NULL DEFAULT 0 "_ns);
+    NS_ENSURE_SUCCESS(rv, rv);
+  }
+
+  rv = mMainConn->CreateStatement(
+      "SELECT scrolling_distance FROM moz_places_metadata"_ns,
+      getter_AddRefs(stmt));
+  if (NS_FAILED(rv)) {
+    rv = mMainConn->ExecuteSimpleSQL(
+        "ALTER TABLE moz_places_metadata "
+        "ADD COLUMN scrolling_distance INTEGER NOT NULL DEFAULT 0 "_ns);
+    NS_ENSURE_SUCCESS(rv, rv);
+  }
+  return NS_OK;
+}
+
+nsresult Database::MigrateV60Up() {
+  // Add the site_name column to moz_places.
+  nsCOMPtr<mozIStorageStatement> stmt;
+  nsresult rv = mMainConn->CreateStatement(
+      "SELECT site_name FROM moz_places"_ns, getter_AddRefs(stmt));
+  if (NS_FAILED(rv)) {
+    rv = mMainConn->ExecuteSimpleSQL(
+        "ALTER TABLE moz_places ADD COLUMN site_name TEXT"_ns);
+    NS_ENSURE_SUCCESS(rv, rv);
+  }
+  return NS_OK;
+}
+
+nsresult Database::MigrateV61Up() {
+  // Add previews tombstones table if necessary.
+  nsCOMPtr<mozIStorageStatement> stmt;
+  nsresult rv = mMainConn->CreateStatement(
+      "SELECT hash FROM moz_previews_tombstones"_ns, getter_AddRefs(stmt));
+  if (NS_FAILED(rv)) {
+    rv = mMainConn->ExecuteSimpleSQL(CREATE_MOZ_PREVIEWS_TOMBSTONES);
+    NS_ENSURE_SUCCESS(rv, rv);
+  }
+  return NS_OK;
+}
+
+nsresult Database::MigrateV67Up() {
+  // Align all input field in moz_inputhistory to lowercase. If there are
+  // multiple records that expresses the same input, use maximum use_count from
+  // them to carry on the experience of the past.
+  nsCOMPtr<mozIStorageStatement> stmt;
+  nsresult rv = mMainConn->ExecuteSimpleSQL(
+      "INSERT INTO moz_inputhistory "
+      "SELECT place_id, LOWER(input), use_count FROM moz_inputhistory "
+      "  WHERE LOWER(input) <> input "
+      "ON CONFLICT DO "
+      "  UPDATE SET use_count = MAX(use_count, EXCLUDED.use_count)"_ns);
+  NS_ENSURE_SUCCESS(rv, rv);
+  rv = mMainConn->ExecuteSimpleSQL(
+      "DELETE FROM moz_inputhistory WHERE LOWER(input) <> input"_ns);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  return NS_OK;
+}
+
+nsresult Database::MigrateV69Up() {
+  // Add source and annotation column to places table.
+  nsCOMPtr<mozIStorageStatement> stmt;
+  nsresult rv = mMainConn->CreateStatement(
+      "SELECT source FROM moz_historyvisits"_ns, getter_AddRefs(stmt));
+  if (NS_FAILED(rv)) {
+    rv = mMainConn->ExecuteSimpleSQL(
+        "ALTER TABLE moz_historyvisits "
+        "ADD COLUMN source INTEGER DEFAULT 0 NOT NULL"_ns);
+    NS_ENSURE_SUCCESS(rv, rv);
+    rv = mMainConn->ExecuteSimpleSQL(
+        "ALTER TABLE moz_historyvisits "
+        "ADD COLUMN triggeringPlaceId INTEGER"_ns);
+    NS_ENSURE_SUCCESS(rv, rv);
+  }
+
+  return NS_OK;
+}
+
+nsresult Database::MigrateV70Up() {
+  nsCOMPtr<mozIStorageStatement> stmt;
+  nsresult rv = mMainConn->CreateStatement(
+      "SELECT recalc_frecency FROM moz_places LIMIT 1 "_ns,
+      getter_AddRefs(stmt));
+  if (NS_FAILED(rv)) {
+    // Add recalc_frecency column, indicating frecency has to be recalculated.
+    rv = mMainConn->ExecuteSimpleSQL(
+        "ALTER TABLE moz_places "
+        "ADD COLUMN recalc_frecency INTEGER NOT NULL DEFAULT 0 "_ns);
+    NS_ENSURE_SUCCESS(rv, rv);
+  }
+
+  // We must do the following updates regardless, for downgrade/upgrade cases.
+
+  // moz_origins frecency is, at the time of this migration, the sum of all the
+  // positive frecencies of pages linked to that origin. Frecencies that were
+  // set to negative to request recalculation are thus not accounted for, and
+  // since we're about to flip them to positive we should add them to their
+  // origin. Then we must also update origins stats.
+  // We ignore frecency = -1 because it's just an indication to recalculate
+  // frecency and not an actual frecency value that was flipped, thus it would
+  // not make sense to count it for the origin.
+  rv = mMainConn->ExecuteSimpleSQL(
+      "UPDATE moz_origins "
+      "SET frecency = frecency + abs_frecency "
+      "FROM (SELECT origin_id, ABS(frecency) AS abs_frecency FROM moz_places "
+      "WHERE frecency < -1) AS places "
+      "WHERE moz_origins.id = places.origin_id"_ns);
+  NS_ENSURE_SUCCESS(rv, rv);
+  rv = RecalculateOriginFrecencyStatsInternal();
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  // Now set recalc_frecency = 1 and positive frecency to any page having a
+  // negative frecency.
+  // Note we don't flip frecency = -1, since we skipped it above when updating
+  // origins, and it remains an acceptable value yet, until the recalculation.
+  rv = mMainConn->ExecuteSimpleSQL(
+      "UPDATE moz_places "
+      "SET recalc_frecency = 1, "
+      "    frecency = CASE WHEN frecency = -1 THEN -1 ELSE ABS(frecency) END "
+      "WHERE frecency < 0 "_ns);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  return NS_OK;
+}
+
+nsresult Database::MigrateV71Up() {
+  // Fix the foreign counts. We ignore failures as the tables may not exist.
+  mMainConn->ExecuteSimpleSQL(
+      "UPDATE moz_places "
+      "SET foreign_count = foreign_count - 1 "
+      "WHERE id in (SELECT place_id FROM moz_places_metadata_snapshots)"_ns);
+  mMainConn->ExecuteSimpleSQL(
+      "UPDATE moz_places "
+      "SET foreign_count = foreign_count - 1 "
+      "WHERE id in (SELECT place_id FROM moz_session_to_places)"_ns);
+
+  // Remove unused snapshots and session tables and indexes.
+  nsresult rv = mMainConn->ExecuteSimpleSQL(
+      "DROP INDEX IF EXISTS moz_places_metadata_snapshots_pinnedindex"_ns);
+  NS_ENSURE_SUCCESS(rv, rv);
+  rv = mMainConn->ExecuteSimpleSQL(
+      "DROP INDEX IF EXISTS moz_places_metadata_snapshots_extra_typeindex"_ns);
+  NS_ENSURE_SUCCESS(rv, rv);
+  rv = mMainConn->ExecuteSimpleSQL(
+      "DROP TABLE IF EXISTS moz_places_metadata_groups_to_snapshots"_ns);
+  NS_ENSURE_SUCCESS(rv, rv);
+  rv = mMainConn->ExecuteSimpleSQL(
+      "DROP TABLE IF EXISTS moz_places_metadata_snapshots_groups"_ns);
+  NS_ENSURE_SUCCESS(rv, rv);
+  rv = mMainConn->ExecuteSimpleSQL(
+      "DROP TABLE IF EXISTS moz_places_metadata_snapshots_extra"_ns);
+  NS_ENSURE_SUCCESS(rv, rv);
+  rv = mMainConn->ExecuteSimpleSQL(
+      "DROP TABLE IF EXISTS moz_places_metadata_snapshots"_ns);
+  NS_ENSURE_SUCCESS(rv, rv);
+  rv = mMainConn->ExecuteSimpleSQL(
+      "DROP TABLE IF EXISTS moz_session_to_places"_ns);
+  NS_ENSURE_SUCCESS(rv, rv);
+  rv = mMainConn->ExecuteSimpleSQL(
+      "DROP TABLE IF EXISTS moz_session_metadata"_ns);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  return NS_OK;
+}
+
+nsresult Database::RecalculateOriginFrecencyStatsInternal() {
+  return mMainConn->ExecuteSimpleSQL(nsLiteralCString(
+      "INSERT OR REPLACE INTO moz_meta(key, value) VALUES "
+      "( "
+      "'" MOZ_META_KEY_ORIGIN_FRECENCY_COUNT
+      "' , "
+      "(SELECT COUNT(*) FROM moz_origins WHERE frecency > 0) "
+      "), "
+      "( "
+      "'" MOZ_META_KEY_ORIGIN_FRECENCY_SUM
+      "', "
+      "(SELECT TOTAL(frecency) FROM moz_origins WHERE frecency > 0) "
+      "), "
+      "( "
+      "'" MOZ_META_KEY_ORIGIN_FRECENCY_SUM_OF_SQUARES
+      "' , "
+      "(SELECT TOTAL(frecency * frecency) FROM moz_origins WHERE frecency > 0) "
+      ") "));
+}
+
+nsresult Database::ConvertOldStyleQuery(nsCString& aURL) {
+  AutoTArray<QueryKeyValuePair, 8> tokens;
+  nsresult rv = TokenizeQueryString(aURL, &tokens);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  AutoTArray<QueryKeyValuePair, 8> newTokens;
+  bool invalid = false;
+  nsAutoCString guid;
+
+  for (uint32_t j = 0; j < tokens.Length(); ++j) {
+    const QueryKeyValuePair& kvp = tokens[j];
+
+    if (!kvp.key.EqualsLiteral("folder")) {
+      // XXX(Bug 1631371) Check if this should use a fallible operation as it
+      // pretended earlier.
+      newTokens.AppendElement(kvp);
+      continue;
+    }
+
+    int64_t itemId = kvp.value.ToInteger(&rv);
+    if (NS_SUCCEEDED(rv)) {
+      // We have the folder's ID, now to find its GUID.
+      nsCOMPtr<mozIStorageStatement> stmt;
+      nsresult rv = mMainConn->CreateStatement(
+          nsLiteralCString("SELECT guid FROM moz_bookmarks "
+                           "WHERE id = :itemId "),
+          getter_AddRefs(stmt));
+      if (NS_FAILED(rv)) return rv;
+
+      rv = stmt->BindInt64ByName("itemId"_ns, itemId);
+      if (NS_FAILED(rv)) return rv;
+
+      bool hasMore = false;
+      if (NS_SUCCEEDED(stmt->ExecuteStep(&hasMore)) && hasMore) {
+        rv = stmt->GetUTF8String(0, guid);
+        if (NS_FAILED(rv)) return rv;
+      }
+    } else if (kvp.value.EqualsLiteral("PLACES_ROOT")) {
+      guid = nsLiteralCString(ROOT_GUID);
+    } else if (kvp.value.EqualsLiteral("BOOKMARKS_MENU")) {
+      guid = nsLiteralCString(MENU_ROOT_GUID);
+    } else if (kvp.value.EqualsLiteral("TAGS")) {
+      guid = nsLiteralCString(TAGS_ROOT_GUID);
+    } else if (kvp.value.EqualsLiteral("UNFILED_BOOKMARKS")) {
+      guid = nsLiteralCString(UNFILED_ROOT_GUID);
+    } else if (kvp.value.EqualsLiteral("TOOLBAR")) {
+      guid = nsLiteralCString(TOOLBAR_ROOT_GUID);
+    } else if (kvp.value.EqualsLiteral("MOBILE_BOOKMARKS")) {
+      guid = nsLiteralCString(MOBILE_ROOT_GUID);
+    }
+
+    QueryKeyValuePair* newPair;
+    if (guid.IsEmpty()) {
+      // This is invalid, so we'll change this key/value pair to something else
+      // so that the query remains a valid url.
+      newPair = new QueryKeyValuePair("invalidOldParentId"_ns, kvp.value);
+      invalid = true;
+    } else {
+      newPair = new QueryKeyValuePair("parent"_ns, guid);
+    }
+    // XXX(Bug 1631371) Check if this should use a fallible operation as it
+    // pretended earlier.
+    newTokens.AppendElement(*newPair);
+    delete newPair;
+  }
+
+  if (invalid) {
+    // One or more of the folders don't exist, replace with an empty query.
+    newTokens.AppendElement(QueryKeyValuePair("excludeItems"_ns, "1"_ns));
+  }
+
+  TokensToQueryString(newTokens, aURL);
+  return NS_OK;
+}
+
+int64_t Database::CreateMobileRoot() {
+  MOZ_ASSERT(NS_IsMainThread());
+
+  // Create the mobile root, ignoring conflicts if one already exists (for
+  // example, if the user downgraded to an earlier release channel).
+  nsCOMPtr<mozIStorageStatement> createStmt;
+  nsresult rv = mMainConn->CreateStatement(
+      nsLiteralCString(
+          "INSERT OR IGNORE INTO moz_bookmarks "
+          "(type, title, dateAdded, lastModified, guid, position, parent) "
+          "SELECT :item_type, :item_title, :timestamp, :timestamp, :guid, "
+          "IFNULL((SELECT MAX(position) + 1 FROM moz_bookmarks p WHERE "
+          "p.parent = b.id), 0), b.id "
+          "FROM moz_bookmarks b WHERE b.parent = 0"),
+      getter_AddRefs(createStmt));
+  if (NS_FAILED(rv)) return -1;
+
+  rv = createStmt->BindInt32ByName("item_type"_ns,
+                                   nsINavBookmarksService::TYPE_FOLDER);
+  if (NS_FAILED(rv)) return -1;
+  rv = createStmt->BindUTF8StringByName("item_title"_ns,
+                                        nsLiteralCString(MOBILE_ROOT_TITLE));
+  if (NS_FAILED(rv)) return -1;
+  rv = createStmt->BindInt64ByName("timestamp"_ns, RoundedPRNow());
+  if (NS_FAILED(rv)) return -1;
+  rv = createStmt->BindUTF8StringByName("guid"_ns,
+                                        nsLiteralCString(MOBILE_ROOT_GUID));
+  if (NS_FAILED(rv)) return -1;
+
+  rv = createStmt->Execute();
+  if (NS_FAILED(rv)) return -1;
+
+  // Find the mobile root ID. We can't use the last inserted ID because the
+  // root might already exist, and we ignore on conflict.
+  nsCOMPtr<mozIStorageStatement> findIdStmt;
+  rv = mMainConn->CreateStatement(
+      "SELECT id FROM moz_bookmarks WHERE guid = :guid"_ns,
+      getter_AddRefs(findIdStmt));
+  if (NS_FAILED(rv)) return -1;
+
+  rv = findIdStmt->BindUTF8StringByName("guid"_ns,
+                                        nsLiteralCString(MOBILE_ROOT_GUID));
+  if (NS_FAILED(rv)) return -1;
+
+  bool hasResult = false;
+  rv = findIdStmt->ExecuteStep(&hasResult);
+  if (NS_FAILED(rv) || !hasResult) return -1;
+
+  int64_t rootId;
+  rv = findIdStmt->GetInt64(0, &rootId);
+  if (NS_FAILED(rv)) return -1;
+
+  return rootId;
+}
+
+void Database::Shutdown() {
+  // As the last step in the shutdown path, finalize the database handle.
+  MOZ_ASSERT(NS_IsMainThread());
+  MOZ_ASSERT(!mClosed);
+
+  // Break cycles with the shutdown blockers.
+  mClientsShutdown = nullptr;
+  nsCOMPtr<mozIStorageCompletionCallback> connectionShutdown =
+      std::move(mConnectionShutdown);
+
+  if (!mMainConn) {
+    // The connection has never been initialized. Just mark it as closed.
+    mClosed = true;
+    (void)connectionShutdown->Complete(NS_OK, nullptr);
+    return;
+  }
+
+#ifdef DEBUG
+  {
+    bool hasResult;
+    nsCOMPtr<mozIStorageStatement> stmt;
+
+    // Sanity check for missing guids.
+    nsresult rv =
+        mMainConn->CreateStatement(nsLiteralCString("SELECT 1 "
+                                                    "FROM moz_places "
+                                                    "WHERE guid IS NULL "),
+                                   getter_AddRefs(stmt));
+    MOZ_ASSERT(NS_SUCCEEDED(rv));
+    rv = stmt->ExecuteStep(&hasResult);
+    MOZ_ASSERT(NS_SUCCEEDED(rv));
+    MOZ_ASSERT(!hasResult, "Found a page without a GUID!");
+    rv = mMainConn->CreateStatement(nsLiteralCString("SELECT 1 "
+                                                     "FROM moz_bookmarks "
+                                                     "WHERE guid IS NULL "),
+                                    getter_AddRefs(stmt));
+    MOZ_ASSERT(NS_SUCCEEDED(rv));
+    rv = stmt->ExecuteStep(&hasResult);
+    MOZ_ASSERT(NS_SUCCEEDED(rv));
+    MOZ_ASSERT(!hasResult, "Found a bookmark without a GUID!");
+
+    // Sanity check for unrounded dateAdded and lastModified values (bug
+    // 1107308).
+    rv = mMainConn->CreateStatement(
+        nsLiteralCString(
+            "SELECT 1 "
+            "FROM moz_bookmarks "
+            "WHERE dateAdded % 1000 > 0 OR lastModified % 1000 > 0 LIMIT 1"),
+        getter_AddRefs(stmt));
+    MOZ_ASSERT(NS_SUCCEEDED(rv));
+    rv = stmt->ExecuteStep(&hasResult);
+    MOZ_ASSERT(NS_SUCCEEDED(rv));
+    MOZ_ASSERT(!hasResult, "Found unrounded dates!");
+
+    // Sanity check url_hash
+    rv = mMainConn->CreateStatement(
+        "SELECT 1 FROM moz_places WHERE url_hash = 0"_ns, getter_AddRefs(stmt));
+    MOZ_ASSERT(NS_SUCCEEDED(rv));
+    rv = stmt->ExecuteStep(&hasResult);
+    MOZ_ASSERT(NS_SUCCEEDED(rv));
+    MOZ_ASSERT(!hasResult, "Found a place without a hash!");
+
+    // Sanity check unique urls
+    rv = mMainConn->CreateStatement(
+        nsLiteralCString(
+            "SELECT 1 FROM moz_places GROUP BY url HAVING count(*) > 1 "),
+        getter_AddRefs(stmt));
+    MOZ_ASSERT(NS_SUCCEEDED(rv));
+    rv = stmt->ExecuteStep(&hasResult);
+    MOZ_ASSERT(NS_SUCCEEDED(rv));
+    MOZ_ASSERT(!hasResult, "Found a duplicate url!");
+
+    // Sanity check NULL urls
+    rv = mMainConn->CreateStatement(
+        "SELECT 1 FROM moz_places WHERE url ISNULL "_ns, getter_AddRefs(stmt));
+    MOZ_ASSERT(NS_SUCCEEDED(rv));
+    rv = stmt->ExecuteStep(&hasResult);
+    MOZ_ASSERT(NS_SUCCEEDED(rv));
+    MOZ_ASSERT(!hasResult, "Found a NULL url!");
+  }
+#endif
+
+  mMainThreadStatements.FinalizeStatements();
+  mMainThreadAsyncStatements.FinalizeStatements();
+
+  RefPtr<FinalizeStatementCacheProxy<mozIStorageStatement>> event =
+      new FinalizeStatementCacheProxy<mozIStorageStatement>(
+          mAsyncThreadStatements, NS_ISUPPORTS_CAST(nsIObserver*, this));
+  DispatchToAsyncThread(event);
+
+  mClosed = true;
+
+  // Execute PRAGMA optimized as last step, this will ensure proper database
+  // performance across restarts.
+  nsCOMPtr<mozIStoragePendingStatement> ps;
+  MOZ_ALWAYS_SUCCEEDS(mMainConn->ExecuteSimpleSQLAsync(
+      "PRAGMA optimize(0x02)"_ns, nullptr, getter_AddRefs(ps)));
+
+  (void)mMainConn->AsyncClose(connectionShutdown);
+  mMainConn = nullptr;
+}
+
+////////////////////////////////////////////////////////////////////////////////
+//// nsIObserver
+
+NS_IMETHODIMP
+Database::Observe(nsISupports* aSubject, const char* aTopic,
+                  const char16_t* aData) {
+  MOZ_ASSERT(NS_IsMainThread());
+  if (strcmp(aTopic, TOPIC_PROFILE_CHANGE_TEARDOWN) == 0) {
+    // Tests simulating shutdown may cause multiple notifications.
+    if (PlacesShutdownBlocker::sIsStarted) {
+      return NS_OK;
+    }
+
+    nsCOMPtr<nsIObserverService> os = services::GetObserverService();
+    NS_ENSURE_STATE(os);
+
+    // If shutdown happens in the same mainthread loop as init, observers could
+    // handle the places-init-complete notification after xpcom-shutdown, when
+    // the connection does not exist anymore.  Removing those observers would
+    // be less expensive but may cause their RemoveObserver calls to throw.
+    // Thus notify the topic now, so they stop listening for it.
+    nsCOMPtr<nsISimpleEnumerator> e;
+    if (NS_SUCCEEDED(os->EnumerateObservers(TOPIC_PLACES_INIT_COMPLETE,
+                                            getter_AddRefs(e))) &&
+        e) {
+      bool hasMore = false;
+      while (NS_SUCCEEDED(e->HasMoreElements(&hasMore)) && hasMore) {
+        nsCOMPtr<nsISupports> supports;
+        if (NS_SUCCEEDED(e->GetNext(getter_AddRefs(supports)))) {
+          nsCOMPtr<nsIObserver> observer = do_QueryInterface(supports);
+          (void)observer->Observe(observer, TOPIC_PLACES_INIT_COMPLETE,
+                                  nullptr);
+        }
+      }
+    }
+
+    // Notify all Places users that we are about to shutdown.
+    (void)os->NotifyObservers(nullptr, TOPIC_PLACES_SHUTDOWN, nullptr);
+  } else if (strcmp(aTopic, TOPIC_SIMULATE_PLACES_SHUTDOWN) == 0) {
+    // This notification is (and must be) only used by tests that are trying
+    // to simulate Places shutdown out of the normal shutdown path.
+
+    // Tests simulating shutdown may cause re-entrance.
+    if (PlacesShutdownBlocker::sIsStarted) {
+      return NS_OK;
+    }
+
+    // We are simulating a shutdown, so invoke the shutdown blockers,
+    // wait for them, then proceed with connection shutdown.
+    // Since we are already going through shutdown, but it's not the real one,
+    // we won't need to block the real one anymore, so we can unblock it.
+    {
+      nsCOMPtr<nsIAsyncShutdownClient> shutdownPhase =
+          GetProfileChangeTeardownPhase();
+      if (shutdownPhase) {
+        shutdownPhase->RemoveBlocker(mClientsShutdown.get());
+      }
+      (void)mClientsShutdown->BlockShutdown(nullptr);
+    }
+
+    // Spin the events loop until the clients are done.
+    // Note, this is just for tests, specifically test_clearHistory_shutdown.js
+    SpinEventLoopUntil("places:Database::Observe(SIMULATE_PLACES_SHUTDOWN)"_ns,
+                       [&]() {
+                         return mClientsShutdown->State() ==
+                                PlacesShutdownBlocker::States::RECEIVED_DONE;
+                       });
+
+    {
+      nsCOMPtr<nsIAsyncShutdownClient> shutdownPhase =
+          GetProfileBeforeChangePhase();
+      if (shutdownPhase) {
+        shutdownPhase->RemoveBlocker(mConnectionShutdown.get());
+      }
+      (void)mConnectionShutdown->BlockShutdown(nullptr);
+    }
+  }
+  return NS_OK;
+}
+
+}  // namespace places
+}  // namespace mozilla