Add new HTTP/2 and HPACK decoder in net/http2/.

net/http2/decoder/payload_decoders/altsvc_payload_decoder.h

Index: net/http2/decoder/payload_decoders/altsvc_payload_decoder.h
diff --git a/net/http2/decoder/payload_decoders/altsvc_payload_decoder.h b/net/http2/decoder/payload_decoders/altsvc_payload_decoder.h
new file mode 100644
index 0000000000000000000000000000000000000000..f92fa7f9db78a48e4895a6fc48acff8bef1eea77
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+++ b/net/http2/decoder/payload_decoders/altsvc_payload_decoder.h
@@ -0,0 +1,64 @@
+// Copyright 2016 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.
+
+#ifndef NET_HTTP2_DECODER_PAYLOAD_DECODERS_ALTSVC_PAYLOAD_DECODER_H_
+#define NET_HTTP2_DECODER_PAYLOAD_DECODERS_ALTSVC_PAYLOAD_DECODER_H_
+
+// Decodes the payload of a ALTSVC frame.
+
+#include "net/base/net_export.h"
+#include "net/http2/decoder/decode_buffer.h"
+#include "net/http2/decoder/decode_status.h"
+#include "net/http2/decoder/frame_decoder_state.h"
+#include "net/http2/http2_structures.h"
+
+namespace net {
+namespace test {
+class AltSvcPayloadDecoderPeer;
+}  // namespace test
+
+class NET_EXPORT_PRIVATE AltSvcPayloadDecoder {
+ public:
+  // States during decoding of a ALTSVC frame.
+  enum class PayloadState {
+    // Start decoding the fixed size structure at the start of an ALTSVC
+    // frame (Http2AltSvcFields).
+    kStartDecodingStruct,
+
+    // Handle the DecodeStatus returned from starting or resuming the
+    // decoding of Http2AltSvcFields. If complete, calls OnAltSvcStart.
+    kMaybeDecodedStruct,
+
+    // Reports the value of the strings (origin and value) of an ALTSVC frame
+    // to the listener.
+    kDecodingStrings,
+
+    // The initial decode buffer wasn't large enough for the Http2AltSvcFields,
+    // so this state resumes the decoding when ResumeDecodingPayload is called
+    // later with a new DecodeBuffer.
+    kResumeDecodingStruct,
+  };
+
+  // Starts the decoding of a ALTSVC frame's payload, and completes it if the
+  // entire payload is in the provided decode buffer.
+  DecodeStatus StartDecodingPayload(FrameDecoderState* state, DecodeBuffer* db);
+
+  // Resumes decoding a ALTSVC frame's payload that has been split across
+  // decode buffers.
+  DecodeStatus ResumeDecodingPayload(FrameDecoderState* state,
+                                     DecodeBuffer* db);
+
+ private:
+  friend class test::AltSvcPayloadDecoderPeer;
+
+  // Implements state kDecodingStrings.
+  DecodeStatus DecodeStrings(FrameDecoderState* state, DecodeBuffer* db);
+
+  Http2AltSvcFields altsvc_fields_;
+  PayloadState payload_state_;
+};
+
+}  // namespace net
+
+#endif  // NET_HTTP2_DECODER_PAYLOAD_DECODERS_ALTSVC_PAYLOAD_DECODER_H_