1 files changed, 49 insertions, 3 deletions

diff --git a/chromium/third_party/blink/renderer/core/streams/readable_stream_byob_reader.h b/chromium/third_party/blink/renderer/core/streams/readable_stream_byob_reader.h
index 198e915cca1..fb7ac5bc9b2 100644
--- a/chromium/third_party/blink/renderer/core/streams/readable_stream_byob_reader.h
+++ b/chromium/third_party/blink/renderer/core/streams/readable_stream_byob_reader.h
@@ -1,4 +1,4 @@
-// Copyright 2020 The Chromium AUthors. All rights reserved.
+// Copyright 2020 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.
 
@@ -9,13 +9,16 @@
 #include "third_party/blink/renderer/core/core_export.h"
 #include "third_party/blink/renderer/core/streams/readable_stream_generic_reader.h"
 #include "third_party/blink/renderer/core/typed_arrays/array_buffer_view_helpers.h"
+#include "third_party/blink/renderer/core/typed_arrays/dom_typed_array.h"
 #include "third_party/blink/renderer/platform/bindings/script_wrappable.h"
+#include "third_party/blink/renderer/platform/wtf/casting.h"
 
 namespace blink {
 
 class ExceptionState;
 class ScriptPromise;
 class ScriptState;
+class StreamPromiseResolver;
 class ReadableStream;
 class DOMArrayBufferView;
 
@@ -34,6 +37,9 @@ class CORE_EXPORT ReadableStreamBYOBReader
                            ExceptionState&);
   ~ReadableStreamBYOBReader() override;
 
+  bool IsDefaultReader() const override { return false; }
+  bool IsBYOBReader() const override { return true; }
+
   // https://streams.spec.whatwg.org/#byob-reader-read
   ScriptPromise read(ScriptState*,
                      NotShared<DOMArrayBufferView> view,
@@ -42,11 +48,51 @@ class CORE_EXPORT ReadableStreamBYOBReader
   // https://streams.spec.whatwg.org/#byob-reader-release-lock
   void releaseLock(ScriptState*, ExceptionState&);
 
+  // https://streams.spec.whatwg.org/#set-up-readable-stream-byob-reader
+  static void SetUpBYOBReader(ScriptState*,
+                              ReadableStreamBYOBReader* reader,
+                              ReadableStream* stream,
+                              ExceptionState&);
+
+  void Trace(Visitor*) const override;
+
  private:
+  friend class ReadableByteStreamController;
   friend class ReadableStream;
-  static void ThrowUnimplemented(ExceptionState&);
-  static ScriptPromise RejectUnimplemented(ScriptState*);
+
+  class ReadIntoRequest : public GarbageCollected<ReadIntoRequest> {
+   public:
+    explicit ReadIntoRequest(StreamPromiseResolver* resolver);
+
+    void ChunkSteps(ScriptState*, DOMArrayBufferView* chunk) const;
+    void CloseSteps(ScriptState*, DOMArrayBufferView* chunk) const;
+    void ErrorSteps(ScriptState*, v8::Local<v8::Value> e) const;
+
+    void Trace(Visitor*) const;
+
+   private:
+    friend class ReadableStream;
+
+    Member<StreamPromiseResolver> resolver_;
+  };
+
+  // https://streams.spec.whatwg.org/#readable-stream-byob-reader-read
+  static void Read(ScriptState*,
+                   ReadableStreamBYOBReader*,
+                   NotShared<DOMArrayBufferView> view,
+                   ReadIntoRequest*,
+                   ExceptionState&);
+
+  HeapDeque<Member<ReadIntoRequest>> read_into_requests_;
 };
+
+template <>
+struct DowncastTraits<ReadableStreamBYOBReader> {
+  static bool AllowFrom(const ReadableStreamGenericReader& reader) {
+    return reader.IsBYOBReader();
+  }
+};
+
 }  // namespace blink
 
 #endif  // THIRD_PARTY_BLINK_RENDERER_CORE_STREAMS_READABLE_STREAM_BYOB_READER_H_