diff -r 000000000000 -r 6474c204b198 dom/file/FileHandle.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/dom/file/FileHandle.cpp	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,195 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "FileHandle.h"
+
+#include "nsContentUtils.h"
+#include "nsDOMClassInfoID.h"
+#include "nsNetUtil.h"
+
+#include "nsIDOMFile.h"
+#include "nsIFileStorage.h"
+
+#include "File.h"
+#include "FileRequest.h"
+#include "FileService.h"
+#include "LockedFile.h"
+#include "MetadataHelper.h"
+#include "mozilla/dom/FileHandleBinding.h"
+
+using namespace mozilla;
+using namespace mozilla::dom;
+USING_FILE_NAMESPACE
+
+namespace {
+
+class GetFileHelper : public MetadataHelper
+{
+public:
+  GetFileHelper(LockedFile* aLockedFile,
+                FileRequest* aFileRequest,
+                MetadataParameters* aParams,
+                FileHandle* aFileHandle)
+  : MetadataHelper(aLockedFile, aFileRequest, aParams),
+    mFileHandle(aFileHandle)
+  { }
+
+  virtual nsresult
+  GetSuccessResult(JSContext* aCx,
+                   JS::MutableHandle<JS::Value> aVal) MOZ_OVERRIDE;
+
+  virtual void
+  ReleaseObjects() MOZ_OVERRIDE
+  {
+    mFileHandle = nullptr;
+
+    MetadataHelper::ReleaseObjects();
+  }
+
+private:
+  nsRefPtr<FileHandle> mFileHandle;
+};
+
+} // anonymous namespace
+
+NS_IMPL_CYCLE_COLLECTION_INHERITED(FileHandle, DOMEventTargetHelper,
+                                   mFileStorage)
+
+NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION_INHERITED(FileHandle)
+NS_INTERFACE_MAP_END_INHERITING(DOMEventTargetHelper)
+
+NS_IMPL_ADDREF_INHERITED(FileHandle, DOMEventTargetHelper)
+NS_IMPL_RELEASE_INHERITED(FileHandle, DOMEventTargetHelper)
+
+// static
+already_AddRefed<FileHandle>
+FileHandle::Create(nsPIDOMWindow* aWindow,
+                   nsIFileStorage* aFileStorage,
+                   nsIFile* aFile)
+{
+  MOZ_ASSERT(NS_IsMainThread(), "Wrong thread!");
+
+  nsRefPtr<FileHandle> newFileHandle = new FileHandle(aWindow);
+
+  newFileHandle->mFileStorage = aFileStorage;
+  nsresult rv = aFile->GetLeafName(newFileHandle->mName);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return nullptr;
+  }
+
+  newFileHandle->mFile = aFile;
+  newFileHandle->mFileName = newFileHandle->mName;
+
+  return newFileHandle.forget();
+}
+
+// virtual
+already_AddRefed<nsISupports>
+FileHandle::CreateStream(nsIFile* aFile, bool aReadOnly)
+{
+  nsresult rv;
+
+  if (aReadOnly) {
+    nsCOMPtr<nsIInputStream> stream;
+    rv = NS_NewLocalFileInputStream(getter_AddRefs(stream), aFile, -1, -1,
+                                    nsIFileInputStream::DEFER_OPEN);
+    if (NS_WARN_IF(NS_FAILED(rv))) {
+      return nullptr;
+    }
+    return stream.forget();
+  }
+
+  nsCOMPtr<nsIFileStream> stream;
+  rv = NS_NewLocalFileStream(getter_AddRefs(stream), aFile, -1, -1,
+                             nsIFileStream::DEFER_OPEN);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return nullptr;
+  }
+  return stream.forget();
+}
+
+// virtual
+already_AddRefed<nsIDOMFile>
+FileHandle::CreateFileObject(LockedFile* aLockedFile, uint32_t aFileSize)
+{
+  nsCOMPtr<nsIDOMFile> file =
+    new File(mName, mType, aFileSize, mFile, aLockedFile);
+
+  return file.forget();
+}
+
+// virtual
+JSObject*
+FileHandle::WrapObject(JSContext* aCx)
+{
+  return FileHandleBinding::Wrap(aCx, this);
+}
+
+already_AddRefed<LockedFile>
+FileHandle::Open(FileMode aMode, ErrorResult& aError)
+{
+  MOZ_ASSERT(NS_IsMainThread());
+
+  if (FileService::IsShuttingDown() || mFileStorage->IsShuttingDown()) {
+    aError.Throw(NS_ERROR_DOM_FILEHANDLE_UNKNOWN_ERR);
+    return nullptr;
+  }
+
+  nsRefPtr<LockedFile> lockedFile = LockedFile::Create(this, aMode);
+  if (!lockedFile) {
+    aError.Throw(NS_ERROR_DOM_FILEHANDLE_UNKNOWN_ERR);
+    return nullptr;
+  }
+
+  return lockedFile.forget();
+}
+
+already_AddRefed<DOMRequest>
+FileHandle::GetFile(ErrorResult& aError)
+{
+  MOZ_ASSERT(NS_IsMainThread());
+
+  // Do nothing if the window is closed
+  if (!GetOwner()) {
+    return nullptr;
+  }
+
+  nsRefPtr<LockedFile> lockedFile =
+    LockedFile::Create(this, FileMode::Readonly, LockedFile::PARALLEL);
+  if (!lockedFile) {
+    aError.Throw(NS_ERROR_DOM_FILEHANDLE_UNKNOWN_ERR);
+    return nullptr;
+  }
+
+  nsRefPtr<FileRequest> request =
+    FileRequest::Create(GetOwner(), lockedFile, /* aWrapAsDOMRequest */ true);
+
+  nsRefPtr<MetadataParameters> params = new MetadataParameters(true, false);
+
+  nsRefPtr<GetFileHelper> helper =
+    new GetFileHelper(lockedFile, request, params, this);
+
+  nsresult rv = helper->Enqueue();
+  if (NS_FAILED(rv)) {
+    aError.Throw(NS_ERROR_DOM_FILEHANDLE_UNKNOWN_ERR);
+    return nullptr;
+  }
+
+  return request.forget();
+}
+
+nsresult
+GetFileHelper::GetSuccessResult(JSContext* aCx,
+                                JS::MutableHandle<JS::Value> aVal)
+{
+  nsCOMPtr<nsIDOMFile> domFile =
+    mFileHandle->CreateFileObject(mLockedFile, mParams->Size());
+
+  nsresult rv =
+    nsContentUtils::WrapNative(aCx, domFile, &NS_GET_IID(nsIDOMFile), aVal);
+  NS_ENSURE_SUCCESS(rv, NS_ERROR_DOM_FILEHANDLE_UNKNOWN_ERR);
+  return NS_OK;
+}