Blob support for IDB [Chromium]

content/browser/indexed_db/indexed_db_factory.cc

 // Copyright (c) 2013 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 "content/browser/indexed_db/indexed_db_factory.h"
 
 #include "base/logging.h"
 #include "base/strings/utf_string_conversions.h"
 #include "base/time/time.h"
 #include "content/browser/indexed_db/indexed_db_backing_store.h"
@@ skipping 22 matching lines @@
   database_map_.erase(it);
 
   // No grace period on a forced-close, as the initiator is
   // assuming the backing store will be released once all
   // connections are closed.
   ReleaseBackingStore(origin_url, forcedClose);
 }
 
 void IndexedDBFactory::ReleaseBackingStore(const GURL& origin_url,
                                            bool immediate) {
+  if (immediate) {
+    IndexedDBBackingStoreMap::iterator it =
+        backing_stores_with_active_blobs_.find(origin_url);
+    if (it != backing_stores_with_active_blobs_.end()) {
+      it->second->active_blob_registry()->ForceShutdown();
+      backing_stores_with_active_blobs_.erase(it);
+    }
+  }
+
   // Only close if this is the last reference.
   if (!HasLastBackingStoreReference(origin_url))
     return;
 
   // If this factory does hold the last reference to the backing store, it can
   // be closed - but unless requested to close it immediately, keep it around
   // for a short period so that a re-open is fast.
   if (immediate) {
     CloseBackingStore(origin_url);
     return;
@@ skipping 40 matching lines @@
 void IndexedDBFactory::ContextDestroyed() {
   // Timers on backing stores hold a reference to this factory. When the
   // context (which nominally owns this factory) is destroyed during thread
   // termination the timers must be stopped so that this factory and the
   // stores can be disposed of.
   for (IndexedDBBackingStoreMap::iterator it = backing_store_map_.begin();
        it != backing_store_map_.end();
        ++it)
     it->second->close_timer()->Stop();
   backing_store_map_.clear();
+  backing_stores_with_active_blobs_.clear();
   context_ = NULL;
 }
 
+void IndexedDBFactory::ReportOutstandingBlobs(const GURL& origin_url,

[jsbell, 2013/12/20 00:44:20]

To untangle this spaghetti, I'd like to turn the factory->backing store
relationship into a "Weak Pointer Map" (abstracted into a class, since that
pattern occurs repeatedly), and pull the responsibility for keeping the BS alive
out.

The Weak Pointer Map would manage a set of weak pointers, with entries removed
from the map when the values were destroyed. (It could be implemented as
std::map<KeyType, WeakPtr<ValueType>> but that would leak)

* databases already do so explicitly
* the "lazy close" could be done by resetting the timer on the BS on connection
close or other points where ReleaseBackingStore is called now; the timer would
just keep a ref alive, drop it when it fired; a forced close would just need to
stop the timer.
* therefore (relevant to this bit of the patch) outstanding blobs would simply
hold a reference to the backing store as long as necessary

+                                              bool blobs_outstanding) {
+  if (!context_)
+    return;
+  if (blobs_outstanding) {
+    DCHECK(!backing_stores_with_active_blobs_.count(origin_url));
+    IndexedDBBackingStoreMap::iterator it = backing_store_map_.find(origin_url);
+    if (it != backing_store_map_.end())
+      backing_stores_with_active_blobs_.insert(*it);
+    else
+      DCHECK(false);
+  } else {
+    IndexedDBBackingStoreMap::iterator it =
+        backing_stores_with_active_blobs_.find(origin_url);
+    if (it != backing_stores_with_active_blobs_.end()) {
+      backing_stores_with_active_blobs_.erase(it);
+      ReleaseBackingStore(origin_url, false);
+    }
+  }
+}
+
 void IndexedDBFactory::GetDatabaseNames(
     scoped_refptr<IndexedDBCallbacks> callbacks,
     const GURL& origin_url,
-    const base::FilePath& data_directory) {
+    const base::FilePath& data_directory,
+    base::TaskRunner* task_runner) {
   IDB_TRACE("IndexedDBFactory::GetDatabaseNames");
   // TODO(dgrogan): Plumb data_loss back to script eventually?
   blink::WebIDBDataLoss data_loss;
   std::string data_loss_message;
   bool disk_full;
   scoped_refptr<IndexedDBBackingStore> backing_store =
       OpenBackingStore(origin_url,
                        data_directory,
+                       NULL,
                        &data_loss,
                        &data_loss_message,
-                       &disk_full);
+                       &disk_full,
+                       task_runner);
   if (!backing_store) {
     callbacks->OnError(
         IndexedDBDatabaseError(blink::WebIDBDatabaseExceptionUnknownError,
                                "Internal error opening backing store for "
                                "indexedDB.webkitGetDatabaseNames."));
     return;
   }
 
   callbacks->OnSuccess(backing_store->GetDatabaseNames());
 }
 
 void IndexedDBFactory::DeleteDatabase(
     const string16& name,
+    net::URLRequestContext* request_context,
     scoped_refptr<IndexedDBCallbacks> callbacks,
     const GURL& origin_url,
-    const base::FilePath& data_directory) {
+    const base::FilePath& data_directory,
+    base::TaskRunner* task_runner) {
   IDB_TRACE("IndexedDBFactory::DeleteDatabase");
   IndexedDBDatabase::Identifier unique_identifier(origin_url, name);
   IndexedDBDatabaseMap::iterator it = database_map_.find(unique_identifier);
   if (it != database_map_.end()) {
     // If there are any connections to the database, directly delete the
     // database.
     it->second->DeleteDatabase(callbacks);
     return;
   }
 
   // TODO(dgrogan): Plumb data_loss back to script eventually?
   blink::WebIDBDataLoss data_loss;
   std::string data_loss_message;
   bool disk_full = false;
   scoped_refptr<IndexedDBBackingStore> backing_store =
       OpenBackingStore(origin_url,
                        data_directory,
+                       request_context,
                        &data_loss,
                        &data_loss_message,
-                       &disk_full);
+                       &disk_full,
+                       task_runner);
   if (!backing_store) {
     callbacks->OnError(
         IndexedDBDatabaseError(blink::WebIDBDatabaseExceptionUnknownError,
                                ASCIIToUTF16(
                                    "Internal error opening backing store "
                                    "for indexedDB.deleteDatabase.")));
     return;
   }
 
   scoped_refptr<IndexedDBDatabase> database =
@@ skipping 17 matching lines @@
   if (!context_)
     return;
   context_->ForceClose(origin_url);
 }
 
 bool IndexedDBFactory::IsBackingStoreOpenForTesting(const GURL& origin_url)
     const {
   return backing_store_map_.find(origin_url) != backing_store_map_.end();
 }
 
+scoped_refptr<IndexedDBBackingStore> IndexedDBFactory::OpenBackingStoreHelper(
+    const GURL& origin_url,
+    const base::FilePath& data_directory,
+    net::URLRequestContext* request_context,
+    blink::WebIDBDataLoss* data_loss,
+    std::string* data_loss_message,
+    bool* disk_full,
+    base::TaskRunner* task_runner,
+    bool first_time) {
+  return IndexedDBBackingStore::Open(this,
+                                     origin_url,
+                                     data_directory,
+                                     request_context,
+                                     data_loss,
+                                     data_loss_message,
+                                     disk_full,
+                                     task_runner,
+                                     first_time);
+}
+
 scoped_refptr<IndexedDBBackingStore> IndexedDBFactory::OpenBackingStore(
     const GURL& origin_url,
     const base::FilePath& data_directory,
+    net::URLRequestContext* request_context,
     blink::WebIDBDataLoss* data_loss,
     std::string* data_loss_message,
-    bool* disk_full) {
+    bool* disk_full,
+    base::TaskRunner* task_runner) {
   const bool open_in_memory = data_directory.empty();
 
   IndexedDBBackingStoreMap::iterator it2 = backing_store_map_.find(origin_url);
   if (it2 != backing_store_map_.end()) {
     it2->second->close_timer()->Stop();
     return it2->second;
   }
 
   scoped_refptr<IndexedDBBackingStore> backing_store;
+  bool first_time = false;
   if (open_in_memory) {
-    backing_store = IndexedDBBackingStore::OpenInMemory(origin_url);
+    // TODO(ericu): Support blobs in in-memory backends.
+    backing_store =
+        IndexedDBBackingStore::OpenInMemory(origin_url, task_runner);
   } else {
-    backing_store = IndexedDBBackingStore::Open(origin_url,
-                                                data_directory,
-                                                data_loss,
-                                                data_loss_message,
-                                                disk_full);
+    first_time = !backends_opened_since_boot_.count(origin_url);
+
+    backing_store = OpenBackingStoreHelper(origin_url,
+                                           data_directory,
+                                           request_context,
+                                           data_loss,
+                                           data_loss_message,
+                                           disk_full,
+                                           task_runner,
+                                           first_time);
   }
 
   if (backing_store.get()) {
+    if (first_time)
+      backends_opened_since_boot_.insert(origin_url);
     backing_store_map_[origin_url] = backing_store;
     // If an in-memory database, bind lifetime to this factory instance.
     if (open_in_memory)
       session_only_backing_stores_.insert(backing_store);
 
     // All backing stores associated with this factory should be of the same
     // type.
-    DCHECK(session_only_backing_stores_.empty() || open_in_memory);
+    DCHECK(session_only_backing_stores_.empty() != open_in_memory);
 
     return backing_store;
   }
 
   return 0;
 }
 
 void IndexedDBFactory::Open(
     const string16& name,
     int64 version,
+    net::URLRequestContext* request_context,
     int64 transaction_id,
     scoped_refptr<IndexedDBCallbacks> callbacks,
     scoped_refptr<IndexedDBDatabaseCallbacks> database_callbacks,
     const GURL& origin_url,
-    const base::FilePath& data_directory) {
+    const base::FilePath& data_directory,
+    int child_process_id,
+    base::TaskRunner* task_runner) {
   IDB_TRACE("IndexedDBFactory::Open");
   scoped_refptr<IndexedDBDatabase> database;
   IndexedDBDatabase::Identifier unique_identifier(origin_url, name);
   IndexedDBDatabaseMap::iterator it = database_map_.find(unique_identifier);
   blink::WebIDBDataLoss data_loss =
       blink::WebIDBDataLossNone;
   std::string data_loss_message;
   bool disk_full = false;
   if (it == database_map_.end()) {
     scoped_refptr<IndexedDBBackingStore> backing_store =
         OpenBackingStore(origin_url,
                          data_directory,
+                         request_context,
                          &data_loss,
                          &data_loss_message,
-                         &disk_full);
+                         &disk_full,
+                         task_runner);
     if (!backing_store) {
       if (disk_full) {
         callbacks->OnError(
             IndexedDBDatabaseError(blink::WebIDBDatabaseExceptionQuotaError,
                                    ASCIIToUTF16(
                                        "Encountered full disk while opening "
                                        "backing store for indexedDB.open.")));
         return;
       }
       callbacks->OnError(IndexedDBDatabaseError(
@@ skipping 13 matching lines @@
       return;
     }
 
     database_map_[unique_identifier] = database;
   } else {
     database = it->second;
   }
 
   database->OpenConnection(callbacks,
                            database_callbacks,
+                           child_process_id,
                            transaction_id,
                            version,
                            data_loss,
                            data_loss_message);
 }
 
 std::vector<IndexedDBDatabase*> IndexedDBFactory::GetOpenDatabasesForOrigin(
     const GURL& origin_url) const {
   std::vector<IndexedDBDatabase*> result;
   for (IndexedDBDatabaseMap::const_iterator it = database_map_.begin();
        it != database_map_.end();
        ++it) {
     if (it->first.first == origin_url)
       result.push_back(it->second.get());
   }
   return result;
 }
 
 }  // namespace content