1 // Copyright (c) 2011 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 CHROME_BROWSER_SYNC_ENGINE_SYNCER_H_
6 #define CHROME_BROWSER_SYNC_ENGINE_SYNCER_H_
7 #pragma once
8
9 #include <utility>
10 #include <vector>
11
12 #include "base/basictypes.h"
13 #include "base/callback.h"
14 #include "base/gtest_prod_util.h"
15 #include "base/memory/scoped_ptr.h"
16 #include "base/synchronization/lock.h"
17 #include "chrome/browser/sync/engine/conflict_resolver.h"
18 #include "chrome/browser/sync/engine/syncer_types.h"
19 #include "chrome/browser/sync/engine/syncproto.h"
20 #include "chrome/browser/sync/sessions/sync_session.h"
21 #include "chrome/browser/sync/syncable/directory_event.h"
22 #include "chrome/browser/sync/syncable/model_type.h"
23 #include "chrome/browser/sync/util/extensions_activity_monitor.h"
24 #include "chrome/common/deprecated/event_sys.h"
25 #include "chrome/common/deprecated/event_sys-inl.h"
26
27 namespace syncable {
28 class Directory;
29 class DirectoryManager;
30 class Entry;
31 class Id;
32 class MutableEntry;
33 class WriteTransaction;
34 } // namespace syncable
35
36 namespace browser_sync {
37
38 class ModelSafeWorker;
39 class ServerConnectionManager;
40 class SyncProcessState;
41 class URLFactory;
42 struct HttpResponse;
43
44 enum SyncerStep {
45 SYNCER_BEGIN,
46 CLEANUP_DISABLED_TYPES,
47 DOWNLOAD_UPDATES,
48 PROCESS_CLIENT_COMMAND,
49 VERIFY_UPDATES,
50 PROCESS_UPDATES,
51 STORE_TIMESTAMPS,
52 APPLY_UPDATES,
53 BUILD_COMMIT_REQUEST,
54 POST_COMMIT_MESSAGE,
55 PROCESS_COMMIT_RESPONSE,
56 BUILD_AND_PROCESS_CONFLICT_SETS,
57 RESOLVE_CONFLICTS,
58 APPLY_UPDATES_TO_RESOLVE_CONFLICTS,
59 CLEAR_PRIVATE_DATA, // TODO(tim): Rename 'private' to 'user'.
60 SYNCER_END
61 };
62
63 // A Syncer provides a control interface for driving the individual steps
64 // of the sync cycle. Each cycle (hopefully) moves the client into closer
65 // synchronization with the server. The individual steps are modeled
66 // as SyncerCommands, and the ordering of the steps is expressed using
67 // the SyncerStep enum.
68 //
69 // A Syncer instance expects to run on a dedicated thread. Calls
70 // to SyncShare() may take an unbounded amount of time, as SyncerCommands
71 // may block on network i/o, on lock contention, or on tasks posted to
72 // other threads.
73 class Syncer {
74 public:
75 typedef std::vector<int64> UnsyncedMetaHandles;
76
77 // The constructor may be called from a thread that is not the Syncer's
78 // dedicated thread, to allow some flexibility in the setup.
79 Syncer();
80 virtual ~Syncer();
81
82 // Called by other threads to tell the syncer to stop what it's doing
83 // and return early from SyncShare, if possible.
84 bool ExitRequested();
85 void RequestEarlyExit();
86
87 // TODO(tim): Deprecated.
88 // Cause one sync cycle to occur. Like a good parent, it is the caller's
89 // responsibility to clean up after the syncer when it finishes a sync share
90 // operation and honor server mandated throttles.
91 virtual void SyncShare(sessions::SyncSession* session);
92
93 // Like SyncShare() above, but |first_step| and |last_step| are provided to
94 // perform a partial sync cycle, stopping after |last_step| is performed.
95 virtual void SyncShare(sessions::SyncSession* session,
96 SyncerStep first_step,
97 SyncerStep last_step);
98
99 private:
100 // Implements the PROCESS_CLIENT_COMMAND syncer step.
101 void ProcessClientCommand(sessions::SyncSession* session);
102
103 bool early_exit_requested_;
104 base::Lock early_exit_requested_lock_;
105
106 ConflictResolver resolver_;
107
108 // A callback hook used in unittests to simulate changes between conflict set
109 // building and conflict resolution.
110 Callback0::Type* pre_conflict_resolution_closure_;
111
112 friend class SyncerTest;
113 FRIEND_TEST_ALL_PREFIXES(SyncerTest, NameClashWithResolver);
114 FRIEND_TEST_ALL_PREFIXES(SyncerTest, IllegalAndLegalUpdates);
115 FRIEND_TEST_ALL_PREFIXES(SusanDeletingTest,
116 NewServerItemInAFolderHierarchyWeHaveDeleted3);
117 FRIEND_TEST_ALL_PREFIXES(SyncerTest, TestCommitListOrderingAndNewParent);
118 FRIEND_TEST_ALL_PREFIXES(SyncerTest,
119 TestCommitListOrderingAndNewParentAndChild);
120 FRIEND_TEST_ALL_PREFIXES(SyncerTest, TestCommitListOrderingCounterexample);
121 FRIEND_TEST_ALL_PREFIXES(SyncerTest, TestCommitListOrderingWithNesting);
122 FRIEND_TEST_ALL_PREFIXES(SyncerTest, TestCommitListOrderingWithNewItems);
123 FRIEND_TEST_ALL_PREFIXES(SyncerTest, TestGetUnsyncedAndSimpleCommit);
124 FRIEND_TEST_ALL_PREFIXES(SyncerTest, TestPurgeWhileUnsynced);
125 FRIEND_TEST_ALL_PREFIXES(SyncerTest, TestPurgeWhileUnapplied);
126 FRIEND_TEST_ALL_PREFIXES(SyncerTest, UnappliedUpdateDuringCommit);
127 FRIEND_TEST_ALL_PREFIXES(SyncerTest, DeletingEntryInFolder);
128 FRIEND_TEST_ALL_PREFIXES(SyncerTest,
129 LongChangelistCreatesFakeOrphanedEntries);
130 FRIEND_TEST_ALL_PREFIXES(SyncerTest, QuicklyMergeDualCreatedHierarchy);
131 FRIEND_TEST_ALL_PREFIXES(SyncerTest, LongChangelistWithApplicationConflict);
132 FRIEND_TEST_ALL_PREFIXES(SyncerTest, DeletingEntryWithLocalEdits);
133 FRIEND_TEST_ALL_PREFIXES(EntryCreatedInNewFolderTest,
134 EntryCreatedInNewFolderMidSync);
135
136 DISALLOW_COPY_AND_ASSIGN(Syncer);
137 };
138
139 // Inline utility functions.
140
141 // Given iterator ranges from two collections sorted according to a common
142 // strict weak ordering, return true if the two ranges contain any common
143 // items, and false if they do not. This function is in this header so that it
144 // can be tested.
145 template <class Iterator1, class Iterator2>
SortedCollectionsIntersect(Iterator1 begin1,Iterator1 end1,Iterator2 begin2,Iterator2 end2)146 bool SortedCollectionsIntersect(Iterator1 begin1, Iterator1 end1,
147 Iterator2 begin2, Iterator2 end2) {
148 Iterator1 i1 = begin1;
149 Iterator2 i2 = begin2;
150 while (i1 != end1 && i2 != end2) {
151 if (*i1 == *i2)
152 return true;
153 if (*i1 > *i2)
154 ++i2;
155 else
156 ++i1;
157 }
158 return false;
159 }
160 // Utility function declarations.
161 void CopyServerFields(syncable::Entry* src, syncable::MutableEntry* dest);
162 void ClearServerData(syncable::MutableEntry* entry);
163
164 } // namespace browser_sync
165
166 #endif // CHROME_BROWSER_SYNC_ENGINE_SYNCER_H_
167
168