1// Copyright 2013 The Chromium Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5#ifndef SYNC_SYNCABLE_DIRECTORY_H_
6#define SYNC_SYNCABLE_DIRECTORY_H_
7
8#include <deque>
9#include <set>
10#include <string>
11#include <vector>
12
13#include "base/basictypes.h"
14#include "base/containers/hash_tables.h"
15#include "base/file_util.h"
16#include "base/gtest_prod_util.h"
17#include "base/values.h"
18#include "sync/base/sync_export.h"
19#include "sync/internal_api/public/util/report_unrecoverable_error_function.h"
20#include "sync/internal_api/public/util/weak_handle.h"
21#include "sync/syncable/dir_open_result.h"
22#include "sync/syncable/entry.h"
23#include "sync/syncable/entry_kernel.h"
24#include "sync/syncable/metahandle_set.h"
25#include "sync/syncable/parent_child_index.h"
26#include "sync/syncable/syncable_delete_journal.h"
27
28namespace syncer {
29
30class Cryptographer;
31class TestUserShare;
32class UnrecoverableErrorHandler;
33
34namespace syncable {
35
36class BaseTransaction;
37class BaseWriteTransaction;
38class DirectoryChangeDelegate;
39class DirectoryBackingStore;
40class NigoriHandler;
41class ScopedKernelLock;
42class TransactionObserver;
43class WriteTransaction;
44
45enum InvariantCheckLevel {
46  OFF = 0,            // No checking.
47  VERIFY_CHANGES = 1, // Checks only mutated entries.  Does not check hierarchy.
48  FULL_DB_VERIFICATION = 2 // Check every entry.  This can be expensive.
49};
50
51// Directory stores and manages EntryKernels.
52//
53// This class is tightly coupled to several other classes (see friends).
54class SYNC_EXPORT Directory {
55  friend class BaseTransaction;
56  friend class Entry;
57  friend class ModelNeutralMutableEntry;
58  friend class MutableEntry;
59  friend class ReadTransaction;
60  friend class ScopedKernelLock;
61  friend class WriteTransaction;
62  friend class SyncableDirectoryTest;
63  friend class syncer::TestUserShare;
64  FRIEND_TEST_ALL_PREFIXES(SyncableDirectoryTest, ManageDeleteJournals);
65  FRIEND_TEST_ALL_PREFIXES(SyncableDirectoryTest,
66                           TakeSnapshotGetsAllDirtyHandlesTest);
67  FRIEND_TEST_ALL_PREFIXES(SyncableDirectoryTest,
68                           TakeSnapshotGetsOnlyDirtyHandlesTest);
69  FRIEND_TEST_ALL_PREFIXES(SyncableDirectoryTest,
70                           TakeSnapshotGetsMetahandlesToPurge);
71
72 public:
73  typedef std::vector<int64> Metahandles;
74
75  // Be careful when using these hash_map containers.  According to the spec,
76  // inserting into them may invalidate all iterators.
77  //
78  // It gets worse, though.  The Anroid STL library has a bug that means it may
79  // invalidate all iterators when you erase from the map, too.  That means that
80  // you can't iterate while erasing.  STLDeleteElements(), std::remove_if(),
81  // and other similar functions are off-limits too, until this bug is fixed.
82  //
83  // See http://sourceforge.net/p/stlport/bugs/239/.
84  typedef base::hash_map<int64, EntryKernel*> MetahandlesMap;
85  typedef base::hash_map<std::string, EntryKernel*> IdsMap;
86  typedef base::hash_map<std::string, EntryKernel*> TagsMap;
87  typedef std::string AttachmentIdUniqueId;
88  typedef base::hash_map<AttachmentIdUniqueId, MetahandleSet>
89      IndexByAttachmentId;
90
91  static const base::FilePath::CharType kSyncDatabaseFilename[];
92
93  // The dirty/clean state of kernel fields backed by the share_info table.
94  // This is public so it can be used in SaveChangesSnapshot for persistence.
95  enum KernelShareInfoStatus {
96    KERNEL_SHARE_INFO_INVALID,
97    KERNEL_SHARE_INFO_VALID,
98    KERNEL_SHARE_INFO_DIRTY
99  };
100
101  // Various data that the Directory::Kernel we are backing (persisting data
102  // for) needs saved across runs of the application.
103  struct SYNC_EXPORT_PRIVATE PersistedKernelInfo {
104    PersistedKernelInfo();
105    ~PersistedKernelInfo();
106
107    // Set the |download_progress| entry for the given model to a
108    // "first sync" start point.  When such a value is sent to the server,
109    // a full download of all objects of the model will be initiated.
110    void ResetDownloadProgress(ModelType model_type);
111
112    // Last sync timestamp fetched from the server.
113    sync_pb::DataTypeProgressMarker download_progress[MODEL_TYPE_COUNT];
114    // Sync-side transaction version per data type. Monotonically incremented
115    // when updating native model. A copy is also saved in native model.
116    // Later out-of-sync models can be detected and fixed by comparing
117    // transaction versions of sync model and native model.
118    // TODO(hatiaol): implement detection and fixing of out-of-sync models.
119    //                Bug 154858.
120    int64 transaction_version[MODEL_TYPE_COUNT];
121    // The store birthday we were given by the server. Contents are opaque to
122    // the client.
123    std::string store_birthday;
124    // The next local ID that has not been used with this cache-GUID.
125    int64 next_id;
126    // The serialized bag of chips we were given by the server. Contents are
127    // opaque to the client. This is the serialization of a message of type
128    // ChipBag defined in sync.proto. It can contains NULL characters.
129    std::string bag_of_chips;
130    // The per-datatype context.
131    sync_pb::DataTypeContext datatype_context[MODEL_TYPE_COUNT];
132  };
133
134  // What the Directory needs on initialization to create itself and its Kernel.
135  // Filled by DirectoryBackingStore::Load.
136  struct KernelLoadInfo {
137    PersistedKernelInfo kernel_info;
138    std::string cache_guid;  // Created on first initialization, never changes.
139    int64 max_metahandle;    // Computed (using sql MAX aggregate) on init.
140    KernelLoadInfo() : max_metahandle(0) {
141    }
142  };
143
144  // When the Directory is told to SaveChanges, a SaveChangesSnapshot is
145  // constructed and forms a consistent snapshot of what needs to be sent to
146  // the backing store.
147  struct SYNC_EXPORT_PRIVATE SaveChangesSnapshot {
148    SaveChangesSnapshot();
149    ~SaveChangesSnapshot();
150
151    KernelShareInfoStatus kernel_info_status;
152    PersistedKernelInfo kernel_info;
153    EntryKernelSet dirty_metas;
154    MetahandleSet metahandles_to_purge;
155    EntryKernelSet delete_journals;
156    MetahandleSet delete_journals_to_purge;
157  };
158
159  // Does not take ownership of |encryptor|.
160  // |report_unrecoverable_error_function| may be NULL.
161  // Takes ownership of |store|.
162  Directory(
163      DirectoryBackingStore* store,
164      UnrecoverableErrorHandler* unrecoverable_error_handler,
165      ReportUnrecoverableErrorFunction
166          report_unrecoverable_error_function,
167      NigoriHandler* nigori_handler,
168      Cryptographer* cryptographer);
169  virtual ~Directory();
170
171  // Does not take ownership of |delegate|, which must not be NULL.
172  // Starts sending events to |delegate| if the returned result is
173  // OPENED.  Note that events to |delegate| may be sent from *any*
174  // thread.  |transaction_observer| must be initialized.
175  DirOpenResult Open(const std::string& name,
176                     DirectoryChangeDelegate* delegate,
177                     const WeakHandle<TransactionObserver>&
178                         transaction_observer);
179
180  // Stops sending events to the delegate and the transaction
181  // observer.
182  void Close();
183
184  int64 NextMetahandle();
185  // Returns a negative integer unique to this client.
186  syncable::Id NextId();
187
188  bool good() const { return NULL != kernel_; }
189
190  // The download progress is an opaque token provided by the sync server
191  // to indicate the continuation state of the next GetUpdates operation.
192  void GetDownloadProgress(
193      ModelType type,
194      sync_pb::DataTypeProgressMarker* value_out) const;
195  void GetDownloadProgressAsString(
196      ModelType type,
197      std::string* value_out) const;
198  size_t GetEntriesCount() const;
199  void SetDownloadProgress(
200      ModelType type,
201      const sync_pb::DataTypeProgressMarker& value);
202
203  // Gets/Increments transaction version of a model type. Must be called when
204  // holding kernel mutex.
205  int64 GetTransactionVersion(ModelType type) const;
206  void IncrementTransactionVersion(ModelType type);
207
208  // Getter/setters for the per datatype context.
209  void GetDataTypeContext(BaseTransaction* trans,
210                          ModelType type,
211                          sync_pb::DataTypeContext* context) const;
212  void SetDataTypeContext(BaseWriteTransaction* trans,
213                          ModelType type,
214                          const sync_pb::DataTypeContext& context);
215
216  ModelTypeSet InitialSyncEndedTypes();
217  bool InitialSyncEndedForType(ModelType type);
218  bool InitialSyncEndedForType(BaseTransaction* trans, ModelType type);
219
220  const std::string& name() const { return kernel_->name; }
221
222  // (Account) Store birthday is opaque to the client, so we keep it in the
223  // format it is in the proto buffer in case we switch to a binary birthday
224  // later.
225  std::string store_birthday() const;
226  void set_store_birthday(const std::string& store_birthday);
227
228  // (Account) Bag of chip is an opaque state used by the server to track the
229  // client.
230  std::string bag_of_chips() const;
231  void set_bag_of_chips(const std::string& bag_of_chips);
232
233  // Unique to each account / client pair.
234  std::string cache_guid() const;
235
236  // Returns a pointer to our Nigori node handler.
237  NigoriHandler* GetNigoriHandler();
238
239  // Returns a pointer to our cryptographer. Does not transfer ownership.
240  // Not thread safe, so should only be accessed while holding a transaction.
241  Cryptographer* GetCryptographer(const BaseTransaction* trans);
242
243  // Returns true if the directory had encountered an unrecoverable error.
244  // Note: Any function in |Directory| that can be called without holding a
245  // transaction need to check if the Directory already has an unrecoverable
246  // error on it.
247  bool unrecoverable_error_set(const BaseTransaction* trans) const;
248
249  // Called to immediately report an unrecoverable error (but don't
250  // propagate it up).
251  void ReportUnrecoverableError() {
252    if (report_unrecoverable_error_function_) {
253      report_unrecoverable_error_function_();
254    }
255  }
256
257  // Called to set the unrecoverable error on the directory and to propagate
258  // the error to upper layers.
259  void OnUnrecoverableError(const BaseTransaction* trans,
260                            const tracked_objects::Location& location,
261                            const std::string & message);
262
263  DeleteJournal* delete_journal();
264
265  // Returns the child meta handles (even those for deleted/unlinked
266  // nodes) for given parent id.  Clears |result| if there are no
267  // children.
268  bool GetChildHandlesById(BaseTransaction*, const Id& parent_id,
269      Metahandles* result);
270
271  // Counts all items under the given node, including the node itself.
272  int GetTotalNodeCount(BaseTransaction*, EntryKernel* kernel_) const;
273
274  // Returns this item's position within its parent folder.
275  // The left-most item is 0, second left-most is 1, etc.
276  int GetPositionIndex(BaseTransaction*, EntryKernel* kernel_) const;
277
278  // Returns true iff |id| has children.
279  bool HasChildren(BaseTransaction* trans, const Id& id);
280
281  // Find the first child in the positional ordering under a parent,
282  // and fill in |*first_child_id| with its id.  Fills in a root Id if
283  // parent has no children.  Returns true if the first child was
284  // successfully found, or false if an error was encountered.
285  Id GetFirstChildId(BaseTransaction* trans, const EntryKernel* parent);
286
287  // These functions allow one to fetch the next or previous item under
288  // the same folder.  Returns the "root" ID if there is no predecessor
289  // or successor.
290  //
291  // TODO(rlarocque): These functions are used mainly for tree traversal.  We
292  // should replace these with an iterator API.  See crbug.com/178275.
293  syncable::Id GetPredecessorId(EntryKernel*);
294  syncable::Id GetSuccessorId(EntryKernel*);
295
296  // Places |e| as a successor to |predecessor|.  If |predecessor| is NULL,
297  // |e| will be placed as the left-most item in its folder.
298  //
299  // Both |e| and |predecessor| must be valid entries under the same parent.
300  //
301  // TODO(rlarocque): This function includes limited support for placing items
302  // with valid positions (ie. Bookmarks) as siblings of items that have no set
303  // ordering (ie. Autofill items).  This support is required only for tests,
304  // and should be removed.  See crbug.com/178282.
305  void PutPredecessor(EntryKernel* e, EntryKernel* predecessor);
306
307  // SaveChanges works by taking a consistent snapshot of the current Directory
308  // state and indices (by deep copy) under a ReadTransaction, passing this
309  // snapshot to the backing store under no transaction, and finally cleaning
310  // up by either purging entries no longer needed (this part done under a
311  // WriteTransaction) or rolling back the dirty bits.  It also uses
312  // internal locking to enforce SaveChanges operations are mutually exclusive.
313  //
314  // WARNING: THIS METHOD PERFORMS SYNCHRONOUS I/O VIA SQLITE.
315  bool SaveChanges();
316
317  // Returns the number of entities with the unsynced bit set.
318  int64 unsynced_entity_count() const;
319
320  // Get GetUnsyncedMetaHandles should only be called after SaveChanges and
321  // before any new entries have been created. The intention is that the
322  // syncer should call it from its PerformSyncQueries member.
323  void GetUnsyncedMetaHandles(BaseTransaction* trans,
324                              Metahandles* result);
325
326  // Returns whether or not this |type| has unapplied updates.
327  bool TypeHasUnappliedUpdates(ModelType type);
328
329  // Get all the metahandles for unapplied updates for a given set of
330  // server types.
331  void GetUnappliedUpdateMetaHandles(BaseTransaction* trans,
332                                     FullModelTypeSet server_types,
333                                     std::vector<int64>* result);
334
335  // Get all the metahandles of entries of |type|.
336  void GetMetaHandlesOfType(BaseTransaction* trans,
337                            ModelType type,
338                            Metahandles* result);
339
340  // Get metahandle counts for various criteria to show on the
341  // about:sync page. The information is computed on the fly
342  // each time. If this results in a significant performance hit,
343  // additional data structures can be added to cache results.
344  void CollectMetaHandleCounts(std::vector<int>* num_entries_by_type,
345                               std::vector<int>* num_to_delete_entries_by_type);
346
347  // Returns a ListValue serialization of all nodes for the given type.
348  scoped_ptr<base::ListValue> GetNodeDetailsForType(
349      BaseTransaction* trans,
350      ModelType type);
351
352  // Sets the level of invariant checking performed after transactions.
353  void SetInvariantCheckLevel(InvariantCheckLevel check_level);
354
355  // Checks tree metadata consistency following a transaction.  It is intended
356  // to provide a reasonable tradeoff between performance and comprehensiveness
357  // and may be used in release code.
358  bool CheckInvariantsOnTransactionClose(
359      syncable::BaseTransaction* trans,
360      const MetahandleSet& modified_handles);
361
362  // Forces a full check of the directory.  This operation may be slow and
363  // should not be invoked outside of tests.
364  bool FullyCheckTreeInvariants(BaseTransaction *trans);
365
366  // Purges data associated with any entries whose ModelType or ServerModelType
367  // is found in |disabled_types|, from sync directory _both_ in memory and on
368  // disk. Only valid, "real" model types are allowed in |disabled_types| (see
369  // model_type.h for definitions).
370  // 1. Data associated with |types_to_journal| is saved in the delete journal
371  // to help prevent back-from-dead problem due to offline delete in the next
372  // sync session. |types_to_journal| must be a subset of |disabled_types|.
373  // 2. Data associated with |types_to_unapply| is reset to an "unapplied"
374  // state, wherein all local data is deleted and IS_UNAPPLIED is set to true.
375  // This is useful when there's no benefit in discarding the currently
376  // downloaded state, such as when there are cryptographer errors.
377  // |types_to_unapply| must be a subset of |disabled_types|.
378  // 3. All other data is purged entirely.
379  // Note: "Purge" is just meant to distinguish from "deleting" entries, which
380  // means something different in the syncable namespace.
381  // WARNING! This can be real slow, as it iterates over all entries.
382  // WARNING! Performs synchronous I/O.
383  // Returns: true on success, false if an error was encountered.
384  virtual bool PurgeEntriesWithTypeIn(ModelTypeSet disabled_types,
385                                      ModelTypeSet types_to_journal,
386                                      ModelTypeSet types_to_unapply);
387
388  // Resets the base_versions and server_versions of all synced entities
389  // associated with |type| to 1.
390  // WARNING! This can be slow, as it iterates over all entries for a type.
391  bool ResetVersionsForType(BaseWriteTransaction* trans, ModelType type);
392
393  // Returns true iff the attachment identified by |attachment_id_proto| is
394  // linked to an entry.
395  //
396  // An attachment linked to a deleted entry is still considered linked if the
397  // entry hasn't yet been purged.
398  bool IsAttachmentLinked(
399      const sync_pb::AttachmentIdProto& attachment_id_proto) const;
400
401  // Given attachment id return metahandles to all entries that reference this
402  // attachment.
403  void GetMetahandlesByAttachmentId(
404      BaseTransaction* trans,
405      const sync_pb::AttachmentIdProto& attachment_id_proto,
406      Metahandles* result);
407
408  // Change entry to not dirty. Used in special case when we don't want to
409  // persist modified entry on disk. e.g. SyncBackupManager uses this to
410  // preserve sync preferences in DB on disk.
411  void UnmarkDirtyEntry(WriteTransaction* trans, Entry* entry);
412
413 protected:  // for friends, mainly used by Entry constructors
414  virtual EntryKernel* GetEntryByHandle(int64 handle);
415  virtual EntryKernel* GetEntryByHandle(int64 metahandle,
416      ScopedKernelLock* lock);
417  virtual EntryKernel* GetEntryById(const Id& id);
418  EntryKernel* GetEntryByServerTag(const std::string& tag);
419  virtual EntryKernel* GetEntryByClientTag(const std::string& tag);
420  bool ReindexId(BaseWriteTransaction* trans, EntryKernel* const entry,
421                 const Id& new_id);
422  bool ReindexParentId(BaseWriteTransaction* trans, EntryKernel* const entry,
423                       const Id& new_parent_id);
424  // Update the attachment index for |metahandle| removing it from the index
425  // under |old_metadata| entries and add it under |new_metadata| entries.
426  void UpdateAttachmentIndex(const int64 metahandle,
427                             const sync_pb::AttachmentMetadata& old_metadata,
428                             const sync_pb::AttachmentMetadata& new_metadata);
429  void ClearDirtyMetahandles();
430
431  DirOpenResult OpenImpl(
432      const std::string& name,
433      DirectoryChangeDelegate* delegate,
434      const WeakHandle<TransactionObserver>& transaction_observer);
435
436 private:
437  struct Kernel {
438    // |delegate| must not be NULL.  |transaction_observer| must be
439    // initialized.
440    Kernel(const std::string& name, const KernelLoadInfo& info,
441           DirectoryChangeDelegate* delegate,
442           const WeakHandle<TransactionObserver>& transaction_observer);
443
444    ~Kernel();
445
446    // Implements ReadTransaction / WriteTransaction using a simple lock.
447    base::Lock transaction_mutex;
448
449    // Protected by transaction_mutex.  Used by WriteTransactions.
450    int64 next_write_transaction_id;
451
452    // The name of this directory.
453    std::string const name;
454
455    // Protects all members below.
456    // The mutex effectively protects all the indices, but not the
457    // entries themselves.  So once a pointer to an entry is pulled
458    // from the index, the mutex can be unlocked and entry read or written.
459    //
460    // Never hold the mutex and do anything with the database or any
461    // other buffered IO.  Violating this rule will result in deadlock.
462    base::Lock mutex;
463
464    // Entries indexed by metahandle.  This container is considered to be the
465    // owner of all EntryKernels, which may be referened by the other
466    // containers.  If you remove an EntryKernel from this map, you probably
467    // want to remove it from all other containers and delete it, too.
468    MetahandlesMap metahandles_map;
469
470    // Entries indexed by id
471    IdsMap ids_map;
472
473    // Entries indexed by server tag.
474    // This map does not include any entries with non-existent server tags.
475    TagsMap server_tags_map;
476
477    // Entries indexed by client tag.
478    // This map does not include any entries with non-existent client tags.
479    // IS_DEL items are included.
480    TagsMap client_tags_map;
481
482    // Contains non-deleted items, indexed according to parent and position
483    // within parent.  Protected by the ScopedKernelLock.
484    ParentChildIndex parent_child_index;
485
486    // This index keeps track of which metahandles refer to a given attachment.
487    // Think of it as the inverse of EntryKernel's AttachmentMetadata Records.
488    //
489    // Because entries can be undeleted (e.g. PutIsDel(false)), entries should
490    // not removed from the index until they are actually deleted from memory.
491    //
492    // All access should go through IsAttachmentLinked,
493    // RemoveFromAttachmentIndex, AddToAttachmentIndex, and
494    // UpdateAttachmentIndex methods to avoid iterator invalidation errors.
495    IndexByAttachmentId index_by_attachment_id;
496
497    // 3 in-memory indices on bits used extremely frequently by the syncer.
498    // |unapplied_update_metahandles| is keyed by the server model type.
499    MetahandleSet unapplied_update_metahandles[MODEL_TYPE_COUNT];
500    MetahandleSet unsynced_metahandles;
501    // Contains metahandles that are most likely dirty (though not
502    // necessarily).  Dirtyness is confirmed in TakeSnapshotForSaveChanges().
503    MetahandleSet dirty_metahandles;
504
505    // When a purge takes place, we remove items from all our indices and stash
506    // them in here so that SaveChanges can persist their permanent deletion.
507    MetahandleSet metahandles_to_purge;
508
509    KernelShareInfoStatus info_status;
510
511    // These 3 members are backed in the share_info table, and
512    // their state is marked by the flag above.
513
514    // A structure containing the Directory state that is written back into the
515    // database on SaveChanges.
516    PersistedKernelInfo persisted_info;
517
518    // A unique identifier for this account's cache db, used to generate
519    // unique server IDs. No need to lock, only written at init time.
520    const std::string cache_guid;
521
522    // It doesn't make sense for two threads to run SaveChanges at the same
523    // time; this mutex protects that activity.
524    base::Lock save_changes_mutex;
525
526    // The next metahandle is protected by kernel mutex.
527    int64 next_metahandle;
528
529    // The delegate for directory change events.  Must not be NULL.
530    DirectoryChangeDelegate* const delegate;
531
532    // The transaction observer.
533    const WeakHandle<TransactionObserver> transaction_observer;
534  };
535
536  // These private versions expect the kernel lock to already be held
537  // before calling.
538  EntryKernel* GetEntryById(const Id& id, ScopedKernelLock* const lock);
539
540  // A helper that implements the logic of checking tree invariants.
541  bool CheckTreeInvariants(syncable::BaseTransaction* trans,
542                           const MetahandleSet& handles);
543
544  // Helper to prime metahandles_map, ids_map, parent_child_index,
545  // unsynced_metahandles, unapplied_update_metahandles, server_tags_map and
546  // client_tags_map from metahandles_index.  The input |handles_map| will be
547  // cleared during the initialization process.
548  void InitializeIndices(MetahandlesMap* handles_map);
549
550  // Constructs a consistent snapshot of the current Directory state and
551  // indices (by deep copy) under a ReadTransaction for use in |snapshot|.
552  // See SaveChanges() for more information.
553  void TakeSnapshotForSaveChanges(SaveChangesSnapshot* snapshot);
554
555  // Purges from memory any unused, safe to remove entries that were
556  // successfully deleted on disk as a result of the SaveChanges that processed
557  // |snapshot|.  See SaveChanges() for more information.
558  bool VacuumAfterSaveChanges(const SaveChangesSnapshot& snapshot);
559
560  // Rolls back dirty bits in the event that the SaveChanges that
561  // processed |snapshot| failed, for example, due to no disk space.
562  void HandleSaveChangesFailure(const SaveChangesSnapshot& snapshot);
563
564  // For new entry creation only
565  bool InsertEntry(BaseWriteTransaction* trans,
566                   EntryKernel* entry, ScopedKernelLock* lock);
567  bool InsertEntry(BaseWriteTransaction* trans, EntryKernel* entry);
568
569  // Used by CheckTreeInvariants
570  void GetAllMetaHandles(BaseTransaction* trans, MetahandleSet* result);
571  bool SafeToPurgeFromMemory(WriteTransaction* trans,
572                             const EntryKernel* const entry) const;
573
574  // A helper used by GetTotalNodeCount.
575  void GetChildSetForKernel(
576      BaseTransaction*,
577      EntryKernel* kernel_,
578      std::deque<const OrderedChildSet*>* child_sets) const;
579
580  // Append the handles of the children of |parent_id| to |result|.
581  void AppendChildHandles(
582      const ScopedKernelLock& lock,
583      const Id& parent_id, Directory::Metahandles* result);
584
585  // Helper methods used by PurgeDisabledTypes.
586  void UnapplyEntry(EntryKernel* entry);
587  void DeleteEntry(bool save_to_journal,
588                   EntryKernel* entry,
589                   EntryKernelSet* entries_to_journal,
590                   const ScopedKernelLock& lock);
591
592  // Remove each of |metahandle|'s attachment ids from index_by_attachment_id.
593  void RemoveFromAttachmentIndex(
594      const int64 metahandle,
595      const sync_pb::AttachmentMetadata& attachment_metadata,
596      const ScopedKernelLock& lock);
597  // Add each of |metahandle|'s attachment ids to the index_by_attachment_id.
598  void AddToAttachmentIndex(
599      const int64 metahandle,
600      const sync_pb::AttachmentMetadata& attachment_metadata,
601      const ScopedKernelLock& lock);
602
603  Kernel* kernel_;
604
605  scoped_ptr<DirectoryBackingStore> store_;
606
607  UnrecoverableErrorHandler* const unrecoverable_error_handler_;
608  const ReportUnrecoverableErrorFunction report_unrecoverable_error_function_;
609  bool unrecoverable_error_set_;
610
611  // Not owned.
612  NigoriHandler* const nigori_handler_;
613  Cryptographer* const cryptographer_;
614
615  InvariantCheckLevel invariant_check_level_;
616
617  // Maintain deleted entries not in |kernel_| until it's verified that they
618  // are deleted in native models as well.
619  scoped_ptr<DeleteJournal> delete_journal_;
620
621  DISALLOW_COPY_AND_ASSIGN(Directory);
622};
623
624}  // namespace syncable
625}  // namespace syncer
626
627#endif // SYNC_SYNCABLE_DIRECTORY_H_
628