1 files changed, 129 insertions, 0 deletions
diff --git a/dom/streams/ReadableStreamBYOBRequest.cpp b/dom/streams/ReadableStreamBYOBRequest.cpp
new file mode 100644
index 0000000000..655b914830
--- /dev/null
+++ b/dom/streams/ReadableStreamBYOBRequest.cpp
@@ -0,0 +1,129 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim:set ts=2 sw=2 sts=2 et cindent: */
+/* 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 "mozilla/dom/ReadableStreamBYOBRequest.h"
+
+#include "mozilla/dom/ByteStreamHelpers.h"
+#include "js/ArrayBuffer.h"
+#include "js/TypeDecls.h"
+#include "mozilla/dom/ReadableByteStreamController.h"
+#include "mozilla/dom/ReadableStream.h"
+#include "mozilla/dom/ReadableStreamBYOBRequestBinding.h"
+#include "js/experimental/TypedData.h"
+#include "mozilla/dom/ReadableStreamController.h"
+#include "nsCOMPtr.h"
+#include "nsIGlobalObject.h"
+#include "nsWrapperCache.h"
+
+namespace mozilla::dom {
+
+using namespace streams_abstract;
+
+ReadableStreamBYOBRequest::ReadableStreamBYOBRequest(nsIGlobalObject* aGlobal)
+    : mGlobal(aGlobal) {
+  mozilla::HoldJSObjects(this);
+}
+
+ReadableStreamBYOBRequest::~ReadableStreamBYOBRequest() {
+  mozilla::DropJSObjects(this);
+}
+
+NS_IMPL_CYCLE_COLLECTION_WRAPPERCACHE_WITH_JS_MEMBERS(ReadableStreamBYOBRequest,
+                                                      (mGlobal, mController),
+                                                      (mView))
+
+NS_IMPL_CYCLE_COLLECTING_ADDREF(ReadableStreamBYOBRequest)
+NS_IMPL_CYCLE_COLLECTING_RELEASE(ReadableStreamBYOBRequest)
+
+NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(ReadableStreamBYOBRequest)
+  NS_WRAPPERCACHE_INTERFACE_MAP_ENTRY
+  NS_INTERFACE_MAP_ENTRY(nsISupports)
+NS_INTERFACE_MAP_END
+
+JSObject* ReadableStreamBYOBRequest::WrapObject(
+    JSContext* aCx, JS::Handle<JSObject*> aGivenProto) {
+  return ReadableStreamBYOBRequest_Binding::Wrap(aCx, this, aGivenProto);
+}
+
+// https://streams.spec.whatwg.org/#rs-byob-request-view
+void ReadableStreamBYOBRequest::GetView(
+    JSContext* cx, JS::MutableHandle<JSObject*> aRetVal) const {
+  // Step 1.
+  aRetVal.set(mView);
+}
+
+// https://streams.spec.whatwg.org/#rs-byob-request-respond
+void ReadableStreamBYOBRequest::Respond(JSContext* aCx, uint64_t bytesWritten,
+                                        ErrorResult& aRv) {
+  // Step 1.
+  if (!mController) {
+    aRv.ThrowTypeError("Undefined Controller");
+    return;
+  }
+
+  // Step 2.
+  bool isSharedMemory;
+  JS::Rooted<JSObject*> view(aCx, mView);
+  JS::Rooted<JSObject*> arrayBuffer(
+      aCx, JS_GetArrayBufferViewBuffer(aCx, view, &isSharedMemory));
+  if (!arrayBuffer) {
+    aRv.StealExceptionFromJSContext(aCx);
+    return;
+  }
+
+  if (JS::IsDetachedArrayBufferObject(arrayBuffer)) {
+    aRv.ThrowTypeError("View of Detached buffer");
+    return;
+  }
+
+  // Step 3.
+  MOZ_ASSERT(JS_GetArrayBufferViewByteLength(view) > 0);
+
+  // Step 4.
+  MOZ_ASSERT(JS::GetArrayBufferByteLength(arrayBuffer) > 0);
+
+  // Step 5.
+  RefPtr<ReadableByteStreamController> controller(mController);
+  ReadableByteStreamControllerRespond(aCx, controller, bytesWritten, aRv);
+}
+
+// https://streams.spec.whatwg.org/#rs-byob-request-respond-with-new-view
+void ReadableStreamBYOBRequest::RespondWithNewView(JSContext* aCx,
+                                                   const ArrayBufferView& view,
+                                                   ErrorResult& aRv) {
+  // Step 1.
+  if (!mController) {
+    aRv.ThrowTypeError("Undefined Controller");
+    return;
+  }
+
+  // Step 2.
+  bool isSharedMemory;
+  JS::Rooted<JSObject*> rootedViewObj(aCx, view.Obj());
+  JS::Rooted<JSObject*> viewedArrayBuffer(
+      aCx, JS_GetArrayBufferViewBuffer(aCx, rootedViewObj, &isSharedMemory));
+  if (!viewedArrayBuffer) {
+    aRv.StealExceptionFromJSContext(aCx);
+    return;
+  }
+
+  if (JS::IsDetachedArrayBufferObject(viewedArrayBuffer)) {
+    aRv.ThrowTypeError("View of Detached Array Buffer");
+    return;
+  }
+
+  // Step 3.
+  RefPtr<ReadableByteStreamController> controller(mController);
+  ReadableByteStreamControllerRespondWithNewView(aCx, controller, rootedViewObj,
+                                                 aRv);
+}
+
+void ReadableStreamBYOBRequest::SetController(
+    ReadableByteStreamController* aController) {
+  mController = aController;
+}
+
+}  // namespace mozilla::dom