1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
|
// Copyright 2014 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "components/sync_driver/tab_node_pool.h"
#include "base/format_macros.h"
#include "base/logging.h"
#include "base/strings/stringprintf.h"
#include "sync/api/sync_change.h"
#include "sync/api/sync_data.h"
#include "sync/internal_api/public/base/model_type.h"
#include "sync/protocol/session_specifics.pb.h"
#include "sync/protocol/sync.pb.h"
namespace browser_sync {
const size_t TabNodePool::kFreeNodesLowWatermark = 25;
const size_t TabNodePool::kFreeNodesHighWatermark = 100;
TabNodePool::TabNodePool()
: max_used_tab_node_id_(kInvalidTabNodeID) {}
// static
// We start vending tab node IDs at 0.
const int TabNodePool::kInvalidTabNodeID = -1;
TabNodePool::~TabNodePool() {}
// Static
std::string TabNodePool::TabIdToTag(
const std::string machine_tag, int tab_node_id) {
return base::StringPrintf("%s %d", machine_tag.c_str(), tab_node_id);
}
void TabNodePool::AddTabNode(int tab_node_id) {
DCHECK_GT(tab_node_id, kInvalidTabNodeID);
DCHECK(nodeid_tabid_map_.find(tab_node_id) == nodeid_tabid_map_.end());
unassociated_nodes_.insert(tab_node_id);
if (max_used_tab_node_id_ < tab_node_id)
max_used_tab_node_id_ = tab_node_id;
}
void TabNodePool::AssociateTabNode(int tab_node_id,
SessionID::id_type tab_id) {
DCHECK_GT(tab_node_id, kInvalidTabNodeID);
// Remove sync node if it is in unassociated nodes pool.
std::set<int>::iterator u_it = unassociated_nodes_.find(tab_node_id);
if (u_it != unassociated_nodes_.end()) {
unassociated_nodes_.erase(u_it);
} else {
// This is a new node association, the sync node should be free.
// Remove node from free node pool and then associate it with the tab.
std::set<int>::iterator it = free_nodes_pool_.find(tab_node_id);
DCHECK(it != free_nodes_pool_.end());
free_nodes_pool_.erase(it);
}
DCHECK(nodeid_tabid_map_.find(tab_node_id) == nodeid_tabid_map_.end());
nodeid_tabid_map_[tab_node_id] = tab_id;
}
int TabNodePool::GetFreeTabNode(syncer::SyncChangeList* append_changes) {
DCHECK_GT(machine_tag_.length(), 0U);
DCHECK(append_changes);
if (free_nodes_pool_.empty()) {
// Tab pool has no free nodes, allocate new one.
int tab_node_id = ++max_used_tab_node_id_;
std::string tab_node_tag = TabIdToTag(machine_tag_, tab_node_id);
// We fill the new node with just enough data so that in case of a crash/bug
// we can identify the node as our own on re-association and reuse it.
sync_pb::EntitySpecifics entity;
sync_pb::SessionSpecifics* specifics = entity.mutable_session();
specifics->set_session_tag(machine_tag_);
specifics->set_tab_node_id(tab_node_id);
append_changes->push_back(syncer::SyncChange(
FROM_HERE,
syncer::SyncChange::ACTION_ADD,
syncer::SyncData::CreateLocalData(tab_node_tag,
tab_node_tag,
entity)));
// Grow the pool by 1 since we created a new node.
DVLOG(1) << "Adding sync node " << tab_node_id
<< " to tab node id pool";
free_nodes_pool_.insert(tab_node_id);
return tab_node_id;
} else {
// Return the next free node.
return *free_nodes_pool_.begin();
}
}
void TabNodePool::FreeTabNode(int tab_node_id,
syncer::SyncChangeList* append_changes) {
DCHECK(append_changes);
TabNodeIDToTabIDMap::iterator it = nodeid_tabid_map_.find(tab_node_id);
DCHECK(it != nodeid_tabid_map_.end());
nodeid_tabid_map_.erase(it);
FreeTabNodeInternal(tab_node_id, append_changes);
}
void TabNodePool::FreeTabNodeInternal(
int tab_node_id,
syncer::SyncChangeList* append_changes) {
DCHECK(free_nodes_pool_.find(tab_node_id) == free_nodes_pool_.end());
DCHECK(append_changes);
free_nodes_pool_.insert(tab_node_id);
// If number of free nodes exceed kFreeNodesHighWatermark,
// delete sync nodes till number reaches kFreeNodesLowWatermark.
// Note: This logic is to mitigate temporary disassociation issues with old
// clients: http://crbug.com/259918. Newer versions do not need this.
if (free_nodes_pool_.size() > kFreeNodesHighWatermark) {
for (std::set<int>::iterator free_it = free_nodes_pool_.begin();
free_it != free_nodes_pool_.end();) {
const std::string tab_node_tag = TabIdToTag(machine_tag_, *free_it);
append_changes->push_back(syncer::SyncChange(
FROM_HERE,
syncer::SyncChange::ACTION_DELETE,
syncer::SyncData::CreateLocalDelete(tab_node_tag,
syncer::SESSIONS)));
free_nodes_pool_.erase(free_it++);
if (free_nodes_pool_.size() <= kFreeNodesLowWatermark) {
return;
}
}
}
}
bool TabNodePool::IsUnassociatedTabNode(int tab_node_id) {
return unassociated_nodes_.find(tab_node_id) != unassociated_nodes_.end();
}
void TabNodePool::ReassociateTabNode(int tab_node_id,
SessionID::id_type tab_id) {
// Remove from list of unassociated sync_nodes if present.
std::set<int>::iterator it = unassociated_nodes_.find(tab_node_id);
if (it != unassociated_nodes_.end()) {
unassociated_nodes_.erase(it);
} else {
// tab_node_id must be an already associated node.
DCHECK(nodeid_tabid_map_.find(tab_node_id) != nodeid_tabid_map_.end());
}
nodeid_tabid_map_[tab_node_id] = tab_id;
}
SessionID::id_type TabNodePool::GetTabIdFromTabNodeId(
int tab_node_id) const {
TabNodeIDToTabIDMap::const_iterator it = nodeid_tabid_map_.find(tab_node_id);
if (it != nodeid_tabid_map_.end()) {
return it->second;
}
return kInvalidTabID;
}
void TabNodePool::DeleteUnassociatedTabNodes(
syncer::SyncChangeList* append_changes) {
for (std::set<int>::iterator it = unassociated_nodes_.begin();
it != unassociated_nodes_.end();) {
FreeTabNodeInternal(*it, append_changes);
unassociated_nodes_.erase(it++);
}
DCHECK(unassociated_nodes_.empty());
}
// Clear tab pool.
void TabNodePool::Clear() {
unassociated_nodes_.clear();
free_nodes_pool_.clear();
nodeid_tabid_map_.clear();
max_used_tab_node_id_ = kInvalidTabNodeID;
}
size_t TabNodePool::Capacity() const {
return nodeid_tabid_map_.size() + unassociated_nodes_.size() +
free_nodes_pool_.size();
}
bool TabNodePool::Empty() const { return free_nodes_pool_.empty(); }
bool TabNodePool::Full() { return nodeid_tabid_map_.empty(); }
void TabNodePool::SetMachineTag(const std::string& machine_tag) {
machine_tag_ = machine_tag;
}
} // namespace browser_sync
|