content/browser/indexed_db/indexed_db_transaction.cc

   1 // Copyright (c) 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 #include "content/browser/indexed_db/indexed_db_transaction.h"
   6
   7 #include "base/bind.h"
   8 #include "base/location.h"
   9 #include "base/logging.h"
  10 #include "base/single_thread_task_runner.h"
  11 #include "base/strings/utf_string_conversions.h"
  12 #include "base/thread_task_runner_handle.h"
  13 #include "content/browser/indexed_db/indexed_db_backing_store.h"
  14 #include "content/browser/indexed_db/indexed_db_cursor.h"
  15 #include "content/browser/indexed_db/indexed_db_database.h"
  16 #include "content/browser/indexed_db/indexed_db_database_callbacks.h"
  17 #include "content/browser/indexed_db/indexed_db_tracing.h"
  18 #include "content/browser/indexed_db/indexed_db_transaction_coordinator.h"
  19 #include "third_party/WebKit/public/platform/modules/indexeddb/WebIDBDatabaseException.h"
  20 #include "third_party/leveldatabase/env_chromium.h"
  21
  22 namespace content {
  23
  24 const int64 kInactivityTimeoutPeriodSeconds = 60;
  25
  26 IndexedDBTransaction::TaskQueue::TaskQueue() {}
  27 IndexedDBTransaction::TaskQueue::~TaskQueue() { clear(); }
  28
  29 void IndexedDBTransaction::TaskQueue::clear() {
  30   while (!queue_.empty())
  31     queue_.pop();
  32 }
  33
  34 IndexedDBTransaction::Operation IndexedDBTransaction::TaskQueue::pop() {
  35   DCHECK(!queue_.empty());
  36   Operation task(queue_.front());
  37   queue_.pop();
  38   return task;
  39 }
  40
  41 IndexedDBTransaction::TaskStack::TaskStack() {}
  42 IndexedDBTransaction::TaskStack::~TaskStack() { clear(); }
  43
  44 void IndexedDBTransaction::TaskStack::clear() {
  45   while (!stack_.empty())
  46     stack_.pop();
  47 }
  48
  49 IndexedDBTransaction::Operation IndexedDBTransaction::TaskStack::pop() {
  50   DCHECK(!stack_.empty());
  51   Operation task(stack_.top());
  52   stack_.pop();
  53   return task;
  54 }
  55
  56 IndexedDBTransaction::IndexedDBTransaction(
  57     int64 id,
  58     scoped_refptr<IndexedDBDatabaseCallbacks> callbacks,
  59     const std::set<int64>& object_store_ids,
  60     blink::WebIDBTransactionMode mode,
  61     IndexedDBDatabase* database,
  62     IndexedDBBackingStore::Transaction* backing_store_transaction)
  63     : id_(id),
  64       object_store_ids_(object_store_ids),
  65       mode_(mode),
  66       used_(false),
  67       state_(CREATED),
  68       commit_pending_(false),
  69       callbacks_(callbacks),
  70       database_(database),
  71       transaction_(backing_store_transaction),
  72       backing_store_transaction_begun_(false),
  73       should_process_queue_(false),
  74       pending_preemptive_events_(0) {
  75   database_->transaction_coordinator().DidCreateTransaction(this);
  76
  77   diagnostics_.tasks_scheduled = 0;
  78   diagnostics_.tasks_completed = 0;
  79   diagnostics_.creation_time = base::Time::Now();
  80 }
  81
  82 IndexedDBTransaction::~IndexedDBTransaction() {
  83   // It shouldn't be possible for this object to get deleted until it's either
  84   // complete or aborted.
  85   DCHECK_EQ(state_, FINISHED);
  86   DCHECK(preemptive_task_queue_.empty());
  87   DCHECK_EQ(pending_preemptive_events_, 0);
  88   DCHECK(task_queue_.empty());
  89   DCHECK(abort_task_stack_.empty());
  90 }
  91
  92 void IndexedDBTransaction::ScheduleTask(blink::WebIDBTaskType type,
  93                                         Operation task) {
  94   DCHECK_NE(state_, COMMITTING);
  95   if (state_ == FINISHED)
  96     return;
  97
  98   timeout_timer_.Stop();
  99   used_ = true;
 100   if (type == blink::WebIDBTaskTypeNormal) {
 101     task_queue_.push(task);
 102     ++diagnostics_.tasks_scheduled;
 103   } else {
 104     preemptive_task_queue_.push(task);
 105   }
 106   RunTasksIfStarted();
 107 }
 108
 109 void IndexedDBTransaction::ScheduleAbortTask(Operation abort_task) {
 110   DCHECK_NE(FINISHED, state_);
 111   DCHECK(used_);
 112   abort_task_stack_.push(abort_task);
 113 }
 114
 115 void IndexedDBTransaction::RunTasksIfStarted() {
 116   DCHECK(used_);
 117
 118   // Not started by the coordinator yet.
 119   if (state_ != STARTED)
 120     return;
 121
 122   // A task is already posted.
 123   if (should_process_queue_)
 124     return;
 125
 126   should_process_queue_ = true;
 127   base::ThreadTaskRunnerHandle::Get()->PostTask(
 128       FROM_HERE, base::Bind(&IndexedDBTransaction::ProcessTaskQueue, this));
 129 }
 130
 131 void IndexedDBTransaction::Abort() {
 132   Abort(IndexedDBDatabaseError(blink::WebIDBDatabaseExceptionUnknownError,
 133                                "Internal error (unknown cause)"));
 134 }
 135
 136 void IndexedDBTransaction::Abort(const IndexedDBDatabaseError& error) {
 137   IDB_TRACE1("IndexedDBTransaction::Abort", "txn.id", id());
 138   if (state_ == FINISHED)
 139     return;
 140
 141   // The last reference to this object may be released while performing the
 142   // abort steps below. We therefore take a self reference to keep ourselves
 143   // alive while executing this method.
 144   scoped_refptr<IndexedDBTransaction> protect(this);
 145
 146   timeout_timer_.Stop();
 147
 148   state_ = FINISHED;
 149   should_process_queue_ = false;
 150
 151   if (backing_store_transaction_begun_)
 152     transaction_->Rollback();
 153
 154   // Run the abort tasks, if any.
 155   while (!abort_task_stack_.empty())
 156     abort_task_stack_.pop().Run(NULL);
 157
 158   preemptive_task_queue_.clear();
 159   pending_preemptive_events_ = 0;
 160   task_queue_.clear();
 161
 162   // Backing store resources (held via cursors) must be released
 163   // before script callbacks are fired, as the script callbacks may
 164   // release references and allow the backing store itself to be
 165   // released, and order is critical.
 166   CloseOpenCursors();
 167   transaction_->Reset();
 168
 169   // Transactions must also be marked as completed before the
 170   // front-end is notified, as the transaction completion unblocks
 171   // operations like closing connections.
 172   database_->transaction_coordinator().DidFinishTransaction(this);
 173 #ifndef NDEBUG
 174   DCHECK(!database_->transaction_coordinator().IsActive(this));
 175 #endif
 176
 177   if (callbacks_.get())
 178     callbacks_->OnAbort(id_, error);
 179
 180   database_->TransactionFinished(this, false);
 181
 182   database_ = NULL;
 183 }
 184
 185 bool IndexedDBTransaction::IsTaskQueueEmpty() const {
 186   return preemptive_task_queue_.empty() && task_queue_.empty();
 187 }
 188
 189 bool IndexedDBTransaction::HasPendingTasks() const {
 190   return pending_preemptive_events_ || !IsTaskQueueEmpty();
 191 }
 192
 193 void IndexedDBTransaction::RegisterOpenCursor(IndexedDBCursor* cursor) {
 194   open_cursors_.insert(cursor);
 195 }
 196
 197 void IndexedDBTransaction::UnregisterOpenCursor(IndexedDBCursor* cursor) {
 198   open_cursors_.erase(cursor);
 199 }
 200
 201 void IndexedDBTransaction::Start() {
 202   // TransactionCoordinator has started this transaction.
 203   DCHECK_EQ(CREATED, state_);
 204   state_ = STARTED;
 205   diagnostics_.start_time = base::Time::Now();
 206
 207   if (!used_)
 208     return;
 209
 210   RunTasksIfStarted();
 211 }
 212
 213 class BlobWriteCallbackImpl : public IndexedDBBackingStore::BlobWriteCallback {
 214  public:
 215   explicit BlobWriteCallbackImpl(
 216       scoped_refptr<IndexedDBTransaction> transaction)
 217       : transaction_(transaction) {}
 218   void Run(bool succeeded) override {
 219     transaction_->BlobWriteComplete(succeeded);
 220   }
 221
 222  protected:
 223   ~BlobWriteCallbackImpl() override {}
 224
 225  private:
 226   scoped_refptr<IndexedDBTransaction> transaction_;
 227 };
 228
 229 void IndexedDBTransaction::BlobWriteComplete(bool success) {
 230   IDB_TRACE("IndexedDBTransaction::BlobWriteComplete");
 231   if (state_ == FINISHED)  // aborted
 232     return;
 233   DCHECK_EQ(state_, COMMITTING);
 234   if (success)
 235     CommitPhaseTwo();
 236   else
 237     Abort(IndexedDBDatabaseError(blink::WebIDBDatabaseExceptionDataError,
 238                                  "Failed to write blobs."));
 239 }
 240
 241 leveldb::Status IndexedDBTransaction::Commit() {
 242   IDB_TRACE1("IndexedDBTransaction::Commit", "txn.id", id());
 243
 244   timeout_timer_.Stop();
 245
 246   // In multiprocess ports, front-end may have requested a commit but
 247   // an abort has already been initiated asynchronously by the
 248   // back-end.
 249   if (state_ == FINISHED)
 250     return leveldb::Status::OK();
 251   DCHECK_NE(state_, COMMITTING);
 252
 253   DCHECK(!used_ || state_ == STARTED);
 254   commit_pending_ = true;
 255
 256   // Front-end has requested a commit, but there may be tasks like
 257   // create_index which are considered synchronous by the front-end
 258   // but are processed asynchronously.
 259   if (HasPendingTasks())
 260     return leveldb::Status::OK();
 261
 262   state_ = COMMITTING;
 263
 264   leveldb::Status s;
 265   if (!used_) {
 266     s = CommitPhaseTwo();
 267   } else {
 268     scoped_refptr<IndexedDBBackingStore::BlobWriteCallback> callback(
 269         new BlobWriteCallbackImpl(this));
 270     // CommitPhaseOne will call the callback synchronously if there are no blobs
 271     // to write.
 272     s = transaction_->CommitPhaseOne(callback);
 273     if (!s.ok())
 274       Abort(IndexedDBDatabaseError(blink::WebIDBDatabaseExceptionDataError,
 275                                    "Error processing blob journal."));
 276   }
 277
 278   return s;
 279 }
 280
 281 leveldb::Status IndexedDBTransaction::CommitPhaseTwo() {
 282   // Abort may have been called just as the blob write completed.
 283   if (state_ == FINISHED)
 284     return leveldb::Status::OK();
 285
 286   DCHECK_EQ(state_, COMMITTING);
 287
 288   // The last reference to this object may be released while performing the
 289   // commit steps below. We therefore take a self reference to keep ourselves
 290   // alive while executing this method.
 291   scoped_refptr<IndexedDBTransaction> protect(this);
 292
 293   state_ = FINISHED;
 294
 295   leveldb::Status s;
 296   bool committed;
 297   if (!used_) {
 298     committed = true;
 299   } else {
 300     s = transaction_->CommitPhaseTwo();
 301     committed = s.ok();
 302   }
 303
 304   // Backing store resources (held via cursors) must be released
 305   // before script callbacks are fired, as the script callbacks may
 306   // release references and allow the backing store itself to be
 307   // released, and order is critical.
 308   CloseOpenCursors();
 309   transaction_->Reset();
 310
 311   // Transactions must also be marked as completed before the
 312   // front-end is notified, as the transaction completion unblocks
 313   // operations like closing connections.
 314   database_->transaction_coordinator().DidFinishTransaction(this);
 315
 316   if (committed) {
 317     abort_task_stack_.clear();
 318     {
 319       IDB_TRACE1(
 320           "IndexedDBTransaction::CommitPhaseTwo.TransactionCompleteCallbacks",
 321           "txn.id", id());
 322       callbacks_->OnComplete(id_);
 323     }
 324     database_->TransactionFinished(this, true);
 325   } else {
 326     while (!abort_task_stack_.empty())
 327       abort_task_stack_.pop().Run(NULL);
 328
 329     IndexedDBDatabaseError error;
 330     if (leveldb_env::IndicatesDiskFull(s)) {
 331       error = IndexedDBDatabaseError(
 332           blink::WebIDBDatabaseExceptionQuotaError,
 333           "Encountered disk full while committing transaction.");
 334     } else {
 335       error = IndexedDBDatabaseError(blink::WebIDBDatabaseExceptionUnknownError,
 336                                      "Internal error committing transaction.");
 337     }
 338     callbacks_->OnAbort(id_, error);
 339
 340     database_->TransactionFinished(this, false);
 341     database_->TransactionCommitFailed(s);
 342   }
 343
 344   database_ = NULL;
 345   return s;
 346 }
 347
 348 void IndexedDBTransaction::ProcessTaskQueue() {
 349   IDB_TRACE1("IndexedDBTransaction::ProcessTaskQueue", "txn.id", id());
 350
 351   // May have been aborted.
 352   if (!should_process_queue_)
 353     return;
 354
 355   DCHECK(!IsTaskQueueEmpty());
 356   should_process_queue_ = false;
 357
 358   if (!backing_store_transaction_begun_) {
 359     transaction_->Begin();
 360     backing_store_transaction_begun_ = true;
 361   }
 362
 363   // The last reference to this object may be released while performing the
 364   // tasks. Take take a self reference to keep this object alive so that
 365   // the loop termination conditions can be checked.
 366   scoped_refptr<IndexedDBTransaction> protect(this);
 367
 368   TaskQueue* task_queue =
 369       pending_preemptive_events_ ? &preemptive_task_queue_ : &task_queue_;
 370   while (!task_queue->empty() && state_ != FINISHED) {
 371     DCHECK_EQ(state_, STARTED);
 372     Operation task(task_queue->pop());
 373     task.Run(this);
 374     if (!pending_preemptive_events_) {
 375       DCHECK(diagnostics_.tasks_completed < diagnostics_.tasks_scheduled);
 376       ++diagnostics_.tasks_completed;
 377     }
 378
 379     // Event itself may change which queue should be processed next.
 380     task_queue =
 381         pending_preemptive_events_ ? &preemptive_task_queue_ : &task_queue_;
 382   }
 383
 384   // If there are no pending tasks, we haven't already committed/aborted,
 385   // and the front-end requested a commit, it is now safe to do so.
 386   if (!HasPendingTasks() && state_ != FINISHED && commit_pending_) {
 387     Commit();
 388     return;
 389   }
 390
 391   // The transaction may have been aborted while processing tasks.
 392   if (state_ == FINISHED)
 393     return;
 394
 395   DCHECK(state_ == STARTED);
 396
 397   // Otherwise, start a timer in case the front-end gets wedged and
 398   // never requests further activity. Read-only transactions don't
 399   // block other transactions, so don't time those out.
 400   if (mode_ != blink::WebIDBTransactionModeReadOnly) {
 401     timeout_timer_.Start(FROM_HERE, GetInactivityTimeout(),
 402                          base::Bind(&IndexedDBTransaction::Timeout, this));
 403   }
 404 }
 405
 406 base::TimeDelta IndexedDBTransaction::GetInactivityTimeout() const {
 407   return base::TimeDelta::FromSeconds(kInactivityTimeoutPeriodSeconds);
 408 }
 409
 410 void IndexedDBTransaction::Timeout() {
 411   Abort(IndexedDBDatabaseError(
 412       blink::WebIDBDatabaseExceptionTimeoutError,
 413       base::ASCIIToUTF16("Transaction timed out due to inactivity.")));
 414 }
 415
 416 void IndexedDBTransaction::CloseOpenCursors() {
 417   IDB_TRACE1("IndexedDBTransaction::CloseOpenCursors", "txn.id", id());
 418   for (auto* cursor : open_cursors_)
 419     cursor->Close();
 420   open_cursors_.clear();
 421 }
 422
 423 }  // namespace content