Switch to using the async DomStorage IPC messages and add a caching layer …

webkit/dom_storage/dom_storage_area.cc

 // Copyright (c) 2012 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 "webkit/dom_storage/dom_storage_area.h"
 
 #include "base/bind.h"
 #include "base/file_util.h"
 #include "base/location.h"
 #include "base/logging.h"
@@ skipping 40 matching lines @@
       name.BaseName().RemoveExtension());
   return DatabaseUtil::GetOriginFromIdentifier(origin_id);
 }
 
 DomStorageArea::DomStorageArea(
     int64 namespace_id, const GURL& origin,
     const FilePath& directory, DomStorageTaskRunner* task_runner)
     : namespace_id_(namespace_id), origin_(origin),
       directory_(directory),
       task_runner_(task_runner),
-      map_(new DomStorageMap(kPerAreaQuota)),
+      map_(new DomStorageMap(kPerAreaQuota + kPerAreaOverQuotaAllowance)),
       is_initial_import_done_(true),
       is_shutdown_(false),
       commit_batches_in_flight_(0) {
   if (namespace_id == kLocalStorageNamespaceId && !directory.empty()) {
     FilePath path = directory.Append(DatabaseFileNameFromOrigin(origin_));
     backing_.reset(new DomStorageDatabase(path));
     is_initial_import_done_ = false;
   }
 }
 
@@ skipping 58 matching lines @@
   return success;
 }
 
 bool DomStorageArea::Clear() {
   if (is_shutdown_)
     return false;
   InitialImportIfNeeded();
   if (map_->Length() == 0)
     return false;
 
-  map_ = new DomStorageMap(kPerAreaQuota);
+  map_ = new DomStorageMap(kPerAreaQuota + kPerAreaOverQuotaAllowance);
 
   if (backing_.get()) {
     CommitBatch* commit_batch = CreateCommitBatchIfNeeded();
     commit_batch->clear_all_first = true;
     commit_batch->changed_values.clear();
   }
 
   return true;
 }
 
@@ skipping 18 matching lines @@
   DCHECK(!is_shutdown_);
   if (HasUncommittedChanges()) {
     // TODO(michaeln): This logically deletes the data immediately,
     // and in a matter of a second, deletes the rows from the backing
     // database file, but the file itself will linger until shutdown
     // or purge time. Ideally, this should delete the file more
     // quickly.
     Clear();
     return;
   }
-  map_ = new DomStorageMap(kPerAreaQuota);
+  map_ = new DomStorageMap(kPerAreaQuota + kPerAreaOverQuotaAllowance);
   if (backing_.get()) {
     is_initial_import_done_ = false;
     backing_.reset(new DomStorageDatabase(backing_->file_path()));
     file_util::Delete(backing_->file_path(), false);
     file_util::Delete(
         DomStorageDatabase::GetJournalFilePath(backing_->file_path()), false);
   }
 }
 
 void DomStorageArea::PurgeMemory() {
   DCHECK(!is_shutdown_);
   if (!is_initial_import_done_ ||  // We're not using any memory.
       !backing_.get() ||  // We can't purge anything.
       HasUncommittedChanges())  // We leave things alone with changes pending.
     return;
 
   // Drop the in memory cache, we'll reload when needed.
   is_initial_import_done_ = false;
-  map_ = new DomStorageMap(kPerAreaQuota);
+  map_ = new DomStorageMap(kPerAreaQuota + kPerAreaOverQuotaAllowance);
 
   // Recreate the database object, this frees up the open sqlite connection
   // and its page cache.
   backing_.reset(new DomStorageDatabase(backing_->file_path()));
 }
 
 void DomStorageArea::Shutdown() {
   DCHECK(!is_shutdown_);
   is_shutdown_ = true;
   map_ = NULL;
@@ skipping 94 matching lines @@
     bool success = backing_->CommitChanges(
         commit_batch_->clear_all_first,
         commit_batch_->changed_values);
     DCHECK(success);
   }
   commit_batch_.reset();
   backing_.reset();
 }
 
 }  // namespace dom_storage