1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4
5 #include "webkit/browser/appcache/appcache_group.h"
6
7 #include <algorithm>
8
9 #include "base/bind.h"
10 #include "base/logging.h"
11 #include "base/message_loop/message_loop.h"
12 #include "webkit/browser/appcache/appcache.h"
13 #include "webkit/browser/appcache/appcache_host.h"
14 #include "webkit/browser/appcache/appcache_service.h"
15 #include "webkit/browser/appcache/appcache_storage.h"
16 #include "webkit/browser/appcache/appcache_update_job.h"
17
18 namespace appcache {
19
20 class AppCacheGroup;
21
22 // Use this helper class because we cannot make AppCacheGroup a derived class
23 // of AppCacheHost::Observer as it would create a circular dependency between
24 // AppCacheHost and AppCacheGroup.
25 class AppCacheGroup::HostObserver : public AppCacheHost::Observer {
26 public:
HostObserver(AppCacheGroup * group)27 explicit HostObserver(AppCacheGroup* group) : group_(group) {}
28
29 // Methods for AppCacheHost::Observer.
OnCacheSelectionComplete(AppCacheHost * host)30 virtual void OnCacheSelectionComplete(AppCacheHost* host) OVERRIDE {} // N/A
OnDestructionImminent(AppCacheHost * host)31 virtual void OnDestructionImminent(AppCacheHost* host) OVERRIDE {
32 group_->HostDestructionImminent(host);
33 }
34 private:
35 AppCacheGroup* group_;
36 };
37
AppCacheGroup(AppCacheStorage * storage,const GURL & manifest_url,int64 group_id)38 AppCacheGroup::AppCacheGroup(AppCacheStorage* storage,
39 const GURL& manifest_url,
40 int64 group_id)
41 : group_id_(group_id),
42 manifest_url_(manifest_url),
43 update_status_(IDLE),
44 is_obsolete_(false),
45 is_being_deleted_(false),
46 newest_complete_cache_(NULL),
47 update_job_(NULL),
48 storage_(storage),
49 is_in_dtor_(false) {
50 storage_->working_set()->AddGroup(this);
51 host_observer_.reset(new HostObserver(this));
52 }
53
~AppCacheGroup()54 AppCacheGroup::~AppCacheGroup() {
55 DCHECK(old_caches_.empty());
56 DCHECK(!newest_complete_cache_);
57 DCHECK(restart_update_task_.IsCancelled());
58 DCHECK(queued_updates_.empty());
59
60 is_in_dtor_ = true;
61
62 if (update_job_)
63 delete update_job_;
64 DCHECK_EQ(IDLE, update_status_);
65
66 storage_->working_set()->RemoveGroup(this);
67 storage_->DeleteResponses(manifest_url_, newly_deletable_response_ids_);
68 }
69
AddUpdateObserver(UpdateObserver * observer)70 void AppCacheGroup::AddUpdateObserver(UpdateObserver* observer) {
71 // If observer being added is a host that has been queued for later update,
72 // add observer to a different observer list.
73 AppCacheHost* host = static_cast<AppCacheHost*>(observer);
74 if (queued_updates_.find(host) != queued_updates_.end())
75 queued_observers_.AddObserver(observer);
76 else
77 observers_.AddObserver(observer);
78 }
79
RemoveUpdateObserver(UpdateObserver * observer)80 void AppCacheGroup::RemoveUpdateObserver(UpdateObserver* observer) {
81 observers_.RemoveObserver(observer);
82 queued_observers_.RemoveObserver(observer);
83 }
84
AddCache(AppCache * complete_cache)85 void AppCacheGroup::AddCache(AppCache* complete_cache) {
86 DCHECK(complete_cache->is_complete());
87 complete_cache->set_owning_group(this);
88
89 if (!newest_complete_cache_) {
90 newest_complete_cache_ = complete_cache;
91 return;
92 }
93
94 if (complete_cache->IsNewerThan(newest_complete_cache_)) {
95 old_caches_.push_back(newest_complete_cache_);
96 newest_complete_cache_ = complete_cache;
97
98 // Update hosts of older caches to add a reference to the newest cache.
99 for (Caches::iterator it = old_caches_.begin();
100 it != old_caches_.end(); ++it) {
101 AppCache::AppCacheHosts& hosts = (*it)->associated_hosts();
102 for (AppCache::AppCacheHosts::iterator host_it = hosts.begin();
103 host_it != hosts.end(); ++host_it) {
104 (*host_it)->SetSwappableCache(this);
105 }
106 }
107 } else {
108 old_caches_.push_back(complete_cache);
109 }
110 }
111
RemoveCache(AppCache * cache)112 void AppCacheGroup::RemoveCache(AppCache* cache) {
113 DCHECK(cache->associated_hosts().empty());
114 if (cache == newest_complete_cache_) {
115 AppCache* tmp_cache = newest_complete_cache_;
116 newest_complete_cache_ = NULL;
117 tmp_cache->set_owning_group(NULL); // may cause this group to be deleted
118 } else {
119 scoped_refptr<AppCacheGroup> protect(this);
120
121 Caches::iterator it =
122 std::find(old_caches_.begin(), old_caches_.end(), cache);
123 if (it != old_caches_.end()) {
124 AppCache* tmp_cache = *it;
125 old_caches_.erase(it);
126 tmp_cache->set_owning_group(NULL); // may cause group to be released
127 }
128
129 if (!is_obsolete() && old_caches_.empty() &&
130 !newly_deletable_response_ids_.empty()) {
131 storage_->DeleteResponses(manifest_url_, newly_deletable_response_ids_);
132 newly_deletable_response_ids_.clear();
133 }
134 }
135 }
136
AddNewlyDeletableResponseIds(std::vector<int64> * response_ids)137 void AppCacheGroup::AddNewlyDeletableResponseIds(
138 std::vector<int64>* response_ids) {
139 if (is_being_deleted() || (!is_obsolete() && old_caches_.empty())) {
140 storage_->DeleteResponses(manifest_url_, *response_ids);
141 response_ids->clear();
142 return;
143 }
144
145 if (newly_deletable_response_ids_.empty()) {
146 newly_deletable_response_ids_.swap(*response_ids);
147 return;
148 }
149 newly_deletable_response_ids_.insert(
150 newly_deletable_response_ids_.end(),
151 response_ids->begin(), response_ids->end());
152 response_ids->clear();
153 }
154
StartUpdateWithNewMasterEntry(AppCacheHost * host,const GURL & new_master_resource)155 void AppCacheGroup::StartUpdateWithNewMasterEntry(
156 AppCacheHost* host, const GURL& new_master_resource) {
157 DCHECK(!is_obsolete() && !is_being_deleted());
158 if (is_in_dtor_)
159 return;
160
161 if (!update_job_)
162 update_job_ = new AppCacheUpdateJob(storage_->service(), this);
163
164 update_job_->StartUpdate(host, new_master_resource);
165
166 // Run queued update immediately as an update has been started manually.
167 if (!restart_update_task_.IsCancelled()) {
168 restart_update_task_.Cancel();
169 RunQueuedUpdates();
170 }
171 }
172
CancelUpdate()173 void AppCacheGroup::CancelUpdate() {
174 if (update_job_) {
175 delete update_job_;
176 DCHECK(!update_job_);
177 DCHECK_EQ(IDLE, update_status_);
178 }
179 }
180
QueueUpdate(AppCacheHost * host,const GURL & new_master_resource)181 void AppCacheGroup::QueueUpdate(AppCacheHost* host,
182 const GURL& new_master_resource) {
183 DCHECK(update_job_ && host && !new_master_resource.is_empty());
184 queued_updates_.insert(QueuedUpdates::value_type(host, new_master_resource));
185
186 // Need to know when host is destroyed.
187 host->AddObserver(host_observer_.get());
188
189 // If host is already observing for updates, move host to queued observers
190 // list so that host is not notified when the current update completes.
191 if (FindObserver(host, observers_)) {
192 observers_.RemoveObserver(host);
193 queued_observers_.AddObserver(host);
194 }
195 }
196
RunQueuedUpdates()197 void AppCacheGroup::RunQueuedUpdates() {
198 if (!restart_update_task_.IsCancelled())
199 restart_update_task_.Cancel();
200
201 if (queued_updates_.empty())
202 return;
203
204 QueuedUpdates updates_to_run;
205 queued_updates_.swap(updates_to_run);
206 DCHECK(queued_updates_.empty());
207
208 for (QueuedUpdates::iterator it = updates_to_run.begin();
209 it != updates_to_run.end(); ++it) {
210 AppCacheHost* host = it->first;
211 host->RemoveObserver(host_observer_.get());
212 if (FindObserver(host, queued_observers_)) {
213 queued_observers_.RemoveObserver(host);
214 observers_.AddObserver(host);
215 }
216
217 if (!is_obsolete() && !is_being_deleted())
218 StartUpdateWithNewMasterEntry(host, it->second);
219 }
220 }
221
FindObserver(UpdateObserver * find_me,const ObserverList<UpdateObserver> & observer_list)222 bool AppCacheGroup::FindObserver(UpdateObserver* find_me,
223 const ObserverList<UpdateObserver>& observer_list) {
224 return observer_list.HasObserver(find_me);
225 }
226
ScheduleUpdateRestart(int delay_ms)227 void AppCacheGroup::ScheduleUpdateRestart(int delay_ms) {
228 DCHECK(restart_update_task_.IsCancelled());
229 restart_update_task_.Reset(
230 base::Bind(&AppCacheGroup::RunQueuedUpdates, this));
231 base::MessageLoop::current()->PostDelayedTask(
232 FROM_HERE,
233 restart_update_task_.callback(),
234 base::TimeDelta::FromMilliseconds(delay_ms));
235 }
236
HostDestructionImminent(AppCacheHost * host)237 void AppCacheGroup::HostDestructionImminent(AppCacheHost* host) {
238 queued_updates_.erase(host);
239 if (queued_updates_.empty() && !restart_update_task_.IsCancelled())
240 restart_update_task_.Cancel();
241 }
242
SetUpdateStatus(UpdateStatus status)243 void AppCacheGroup::SetUpdateStatus(UpdateStatus status) {
244 if (status == update_status_)
245 return;
246
247 update_status_ = status;
248
249 if (status != IDLE) {
250 DCHECK(update_job_);
251 } else {
252 update_job_ = NULL;
253
254 // Observers may release us in these callbacks, so we protect against
255 // deletion by adding an extra ref in this scope (but only if we're not
256 // in our destructor).
257 scoped_refptr<AppCacheGroup> protect(is_in_dtor_ ? NULL : this);
258 FOR_EACH_OBSERVER(UpdateObserver, observers_, OnUpdateComplete(this));
259 if (!queued_updates_.empty())
260 ScheduleUpdateRestart(kUpdateRestartDelayMs);
261 }
262 }
263
264 } // namespace appcache
265