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.
5 #include "content/browser/dom_storage/dom_storage_area.h"
8 #include "base/location.h"
9 #include "base/logging.h"
10 #include "base/metrics/histogram.h"
11 #include "base/strings/utf_string_conversions.h"
12 #include "base/time/time.h"
13 #include "content/browser/dom_storage/dom_storage_namespace.h"
14 #include "content/browser/dom_storage/dom_storage_task_runner.h"
15 #include "content/browser/dom_storage/local_storage_database_adapter.h"
16 #include "content/browser/dom_storage/session_storage_database.h"
17 #include "content/browser/dom_storage/session_storage_database_adapter.h"
18 #include "content/common/dom_storage/dom_storage_map.h"
19 #include "content/common/dom_storage/dom_storage_types.h"
20 #include "storage/browser/database/database_util.h"
21 #include "storage/common/database/database_identifier.h"
22 #include "storage/common/fileapi/file_system_util.h"
24 using storage::DatabaseUtil;
28 static const int kCommitTimerSeconds = 1;
30 DOMStorageArea::CommitBatch::CommitBatch()
31 : clear_all_first(false) {
33 DOMStorageArea::CommitBatch::~CommitBatch() {}
37 const base::FilePath::CharType DOMStorageArea::kDatabaseFileExtension[] =
38 FILE_PATH_LITERAL(".localstorage");
41 base::FilePath DOMStorageArea::DatabaseFileNameFromOrigin(const GURL& origin) {
42 std::string filename = storage::GetIdentifierFromOrigin(origin);
43 // There is no base::FilePath.AppendExtension() method, so start with just the
44 // extension as the filename, and then InsertBeforeExtension the desired
46 return base::FilePath().Append(kDatabaseFileExtension).
47 InsertBeforeExtensionASCII(filename);
51 GURL DOMStorageArea::OriginFromDatabaseFileName(const base::FilePath& name) {
52 DCHECK(name.MatchesExtension(kDatabaseFileExtension));
53 std::string origin_id =
54 name.BaseName().RemoveExtension().MaybeAsASCII();
55 return storage::GetOriginFromIdentifier(origin_id);
58 DOMStorageArea::DOMStorageArea(
59 const GURL& origin, const base::FilePath& directory,
60 DOMStorageTaskRunner* task_runner)
61 : namespace_id_(kLocalStorageNamespaceId), origin_(origin),
62 directory_(directory),
63 task_runner_(task_runner),
64 map_(new DOMStorageMap(kPerStorageAreaQuota +
65 kPerStorageAreaOverQuotaAllowance)),
66 is_initial_import_done_(true),
68 commit_batches_in_flight_(0) {
69 if (!directory.empty()) {
70 base::FilePath path = directory.Append(DatabaseFileNameFromOrigin(origin_));
71 backing_.reset(new LocalStorageDatabaseAdapter(path));
72 is_initial_import_done_ = false;
76 DOMStorageArea::DOMStorageArea(
78 const std::string& persistent_namespace_id,
80 SessionStorageDatabase* session_storage_backing,
81 DOMStorageTaskRunner* task_runner)
82 : namespace_id_(namespace_id),
83 persistent_namespace_id_(persistent_namespace_id),
85 task_runner_(task_runner),
86 map_(new DOMStorageMap(kPerStorageAreaQuota +
87 kPerStorageAreaOverQuotaAllowance)),
88 session_storage_backing_(session_storage_backing),
89 is_initial_import_done_(true),
91 commit_batches_in_flight_(0) {
92 DCHECK(namespace_id != kLocalStorageNamespaceId);
93 if (session_storage_backing) {
94 backing_.reset(new SessionStorageDatabaseAdapter(
95 session_storage_backing, persistent_namespace_id, origin));
96 is_initial_import_done_ = false;
100 DOMStorageArea::~DOMStorageArea() {
103 void DOMStorageArea::ExtractValues(DOMStorageValuesMap* map) {
106 InitialImportIfNeeded();
107 map_->ExtractValues(map);
110 unsigned DOMStorageArea::Length() {
113 InitialImportIfNeeded();
114 return map_->Length();
117 base::NullableString16 DOMStorageArea::Key(unsigned index) {
119 return base::NullableString16();
120 InitialImportIfNeeded();
121 return map_->Key(index);
124 base::NullableString16 DOMStorageArea::GetItem(const base::string16& key) {
126 return base::NullableString16();
127 InitialImportIfNeeded();
128 return map_->GetItem(key);
131 bool DOMStorageArea::SetItem(const base::string16& key,
132 const base::string16& value,
133 base::NullableString16* old_value) {
136 InitialImportIfNeeded();
137 if (!map_->HasOneRef())
138 map_ = map_->DeepCopy();
139 bool success = map_->SetItem(key, value, old_value);
140 if (success && backing_) {
141 CommitBatch* commit_batch = CreateCommitBatchIfNeeded();
142 commit_batch->changed_values[key] = base::NullableString16(value, false);
147 bool DOMStorageArea::RemoveItem(const base::string16& key,
148 base::string16* old_value) {
151 InitialImportIfNeeded();
152 if (!map_->HasOneRef())
153 map_ = map_->DeepCopy();
154 bool success = map_->RemoveItem(key, old_value);
155 if (success && backing_) {
156 CommitBatch* commit_batch = CreateCommitBatchIfNeeded();
157 commit_batch->changed_values[key] = base::NullableString16();
162 bool DOMStorageArea::Clear() {
165 InitialImportIfNeeded();
166 if (map_->Length() == 0)
169 map_ = new DOMStorageMap(kPerStorageAreaQuota +
170 kPerStorageAreaOverQuotaAllowance);
173 CommitBatch* commit_batch = CreateCommitBatchIfNeeded();
174 commit_batch->clear_all_first = true;
175 commit_batch->changed_values.clear();
181 void DOMStorageArea::FastClear() {
182 // TODO(marja): Unify clearing localStorage and sessionStorage. The problem is
183 // to make the following 3 to work together: 1) FastClear, 2) PurgeMemory and
184 // 3) not creating events when clearing an empty area.
188 map_ = new DOMStorageMap(kPerStorageAreaQuota +
189 kPerStorageAreaOverQuotaAllowance);
190 // This ensures no import will happen while we're waiting to clear the data
191 // from the database. This mechanism fails if PurgeMemory is called.
192 is_initial_import_done_ = true;
195 CommitBatch* commit_batch = CreateCommitBatchIfNeeded();
196 commit_batch->clear_all_first = true;
197 commit_batch->changed_values.clear();
201 DOMStorageArea* DOMStorageArea::ShallowCopy(
202 int64 destination_namespace_id,
203 const std::string& destination_persistent_namespace_id) {
204 DCHECK_NE(kLocalStorageNamespaceId, namespace_id_);
205 DCHECK_NE(kLocalStorageNamespaceId, destination_namespace_id);
207 DOMStorageArea* copy = new DOMStorageArea(
208 destination_namespace_id, destination_persistent_namespace_id, origin_,
209 session_storage_backing_.get(), task_runner_.get());
211 copy->is_shutdown_ = is_shutdown_;
212 copy->is_initial_import_done_ = true;
214 // All the uncommitted changes to this area need to happen before the actual
215 // shallow copy is made (scheduled by the upper layer). Another OnCommitTimer
216 // call might be in the event queue at this point, but it's handled gracefully
223 bool DOMStorageArea::HasUncommittedChanges() const {
224 DCHECK(!is_shutdown_);
225 return commit_batch_.get() || commit_batches_in_flight_;
228 void DOMStorageArea::DeleteOrigin() {
229 DCHECK(!is_shutdown_);
230 // This function shouldn't be called for sessionStorage.
231 DCHECK(!session_storage_backing_.get());
232 if (HasUncommittedChanges()) {
233 // TODO(michaeln): This logically deletes the data immediately,
234 // and in a matter of a second, deletes the rows from the backing
235 // database file, but the file itself will linger until shutdown
236 // or purge time. Ideally, this should delete the file more
241 map_ = new DOMStorageMap(kPerStorageAreaQuota +
242 kPerStorageAreaOverQuotaAllowance);
244 is_initial_import_done_ = false;
246 backing_->DeleteFiles();
250 void DOMStorageArea::PurgeMemory() {
251 DCHECK(!is_shutdown_);
252 // Purging sessionStorage is not supported; it won't work with FastClear.
253 DCHECK(!session_storage_backing_.get());
254 if (!is_initial_import_done_ || // We're not using any memory.
255 !backing_.get() || // We can't purge anything.
256 HasUncommittedChanges()) // We leave things alone with changes pending.
259 // Drop the in memory cache, we'll reload when needed.
260 is_initial_import_done_ = false;
261 map_ = new DOMStorageMap(kPerStorageAreaQuota +
262 kPerStorageAreaOverQuotaAllowance);
264 // Recreate the database object, this frees up the open sqlite connection
265 // and its page cache.
269 void DOMStorageArea::Shutdown() {
270 DCHECK(!is_shutdown_);
276 bool success = task_runner_->PostShutdownBlockingTask(
278 DOMStorageTaskRunner::COMMIT_SEQUENCE,
279 base::Bind(&DOMStorageArea::ShutdownInCommitSequence, this));
283 void DOMStorageArea::InitialImportIfNeeded() {
284 if (is_initial_import_done_)
287 DCHECK(backing_.get());
289 base::TimeTicks before = base::TimeTicks::Now();
290 DOMStorageValuesMap initial_values;
291 backing_->ReadAllValues(&initial_values);
292 map_->SwapValues(&initial_values);
293 is_initial_import_done_ = true;
294 base::TimeDelta time_to_import = base::TimeTicks::Now() - before;
295 UMA_HISTOGRAM_TIMES("LocalStorage.BrowserTimeToPrimeLocalStorage",
298 size_t local_storage_size_kb = map_->bytes_used() / 1024;
299 // Track localStorage size, from 0-6MB. Note that the maximum size should be
300 // 5MB, but we add some slop since we want to make sure the max size is always
301 // above what we see in practice, since histograms can't change.
302 UMA_HISTOGRAM_CUSTOM_COUNTS("LocalStorage.BrowserLocalStorageSizeInKB",
303 local_storage_size_kb,
305 if (local_storage_size_kb < 100) {
307 "LocalStorage.BrowserTimeToPrimeLocalStorageUnder100KB",
309 } else if (local_storage_size_kb < 1000) {
311 "LocalStorage.BrowserTimeToPrimeLocalStorage100KBTo1MB",
315 "LocalStorage.BrowserTimeToPrimeLocalStorage1MBTo5MB",
320 DOMStorageArea::CommitBatch* DOMStorageArea::CreateCommitBatchIfNeeded() {
321 DCHECK(!is_shutdown_);
322 if (!commit_batch_) {
323 commit_batch_.reset(new CommitBatch());
325 // Start a timer to commit any changes that accrue in the batch, but only if
326 // no commits are currently in flight. In that case the timer will be
327 // started after the commits have happened.
328 if (!commit_batches_in_flight_) {
329 task_runner_->PostDelayedTask(
331 base::Bind(&DOMStorageArea::OnCommitTimer, this),
332 base::TimeDelta::FromSeconds(kCommitTimerSeconds));
335 return commit_batch_.get();
338 void DOMStorageArea::OnCommitTimer() {
342 DCHECK(backing_.get());
344 // It's possible that there is nothing to commit, since a shallow copy occured
345 // before the timer fired.
349 // This method executes on the primary sequence, we schedule
350 // a task for immediate execution on the commit sequence.
351 DCHECK(task_runner_->IsRunningOnPrimarySequence());
352 bool success = task_runner_->PostShutdownBlockingTask(
354 DOMStorageTaskRunner::COMMIT_SEQUENCE,
355 base::Bind(&DOMStorageArea::CommitChanges, this,
356 base::Owned(commit_batch_.release())));
357 ++commit_batches_in_flight_;
361 void DOMStorageArea::CommitChanges(const CommitBatch* commit_batch) {
362 // This method executes on the commit sequence.
363 DCHECK(task_runner_->IsRunningOnCommitSequence());
364 backing_->CommitChanges(commit_batch->clear_all_first,
365 commit_batch->changed_values);
366 // TODO(michaeln): what if CommitChanges returns false (e.g., we're trying to
367 // commit to a DB which is in an inconsistent state?)
368 task_runner_->PostTask(
370 base::Bind(&DOMStorageArea::OnCommitComplete, this));
373 void DOMStorageArea::OnCommitComplete() {
374 // We're back on the primary sequence in this method.
375 DCHECK(task_runner_->IsRunningOnPrimarySequence());
376 --commit_batches_in_flight_;
379 if (commit_batch_.get() && !commit_batches_in_flight_) {
380 // More changes have accrued, restart the timer.
381 task_runner_->PostDelayedTask(
383 base::Bind(&DOMStorageArea::OnCommitTimer, this),
384 base::TimeDelta::FromSeconds(kCommitTimerSeconds));
388 void DOMStorageArea::ShutdownInCommitSequence() {
389 // This method executes on the commit sequence.
390 DCHECK(task_runner_->IsRunningOnCommitSequence());
391 DCHECK(backing_.get());
393 // Commit any changes that accrued prior to the timer firing.
394 bool success = backing_->CommitChanges(
395 commit_batch_->clear_all_first,
396 commit_batch_->changed_values);
399 commit_batch_.reset();
401 session_storage_backing_ = NULL;
404 } // namespace content