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

net/http2/hpack/decoder/hpack_block_decoder.h

Index: net/http2/hpack/decoder/hpack_block_decoder.h
diff --git a/net/http2/hpack/decoder/hpack_block_decoder.h b/net/http2/hpack/decoder/hpack_block_decoder.h
new file mode 100644
index 0000000000000000000000000000000000000000..49e8ae1784241153bdf90d5667fa48d6617f3d4b
--- /dev/null
+++ b/net/http2/hpack/decoder/hpack_block_decoder.h
@@ -0,0 +1,69 @@
+// 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_HPACK_DECODER_HPACK_BLOCK_DECODER_H_
+#define NET_HTTP2_HPACK_DECODER_HPACK_BLOCK_DECODER_H_
+
+// HpackBlockDecoder decodes an entire HPACK block (or the available portion
+// thereof in the DecodeBuffer) into entries, but doesn't include HPACK static
+// or dynamic table support, so table indices remain indices at this level.
+// Reports the entries to an HpackEntryDecoderListener.
+
+#include <string>
+
+#include "base/logging.h"
+#include "base/macros.h"
+#include "net/base/net_export.h"
+#include "net/http2/decoder/decode_buffer.h"
+#include "net/http2/decoder/decode_status.h"
+#include "net/http2/hpack/decoder/hpack_entry_decoder.h"
+#include "net/http2/hpack/decoder/hpack_entry_decoder_listener.h"
+
+namespace net {
+
+class NET_EXPORT_PRIVATE HpackBlockDecoder {
+ public:
+  explicit HpackBlockDecoder(HpackEntryDecoderListener* listener)
+      : listener_(listener) {
+    DCHECK_NE(listener_, nullptr);
+  }
+  ~HpackBlockDecoder() {}
+
+  // The listener may be changed at any time. The change takes effect on the
+  // next entry into the decode loop of the Decode() method below.
+  void set_listener(HpackEntryDecoderListener* listener) {
+    DCHECK_NE(nullptr, listener);
+    listener_ = listener;
+  }
+  HpackEntryDecoderListener* listener() { return listener_; }
+
+  // Prepares the decoder to start decoding a new HPACK block. Expected
+  // to be called from an implementation of Http2FrameDecoderListener's
+  // OnHeadersStart or OnPushPromiseStart methods.
+  void Reset() {
+    DVLOG(2) << "HpackBlockDecoder::Reset";
+    before_entry_ = true;
+  }
+
+  // Decode the fragment of the HPACK block contained in the decode buffer.
+  // Expected to be called from an implementation of Http2FrameDecoderListener's
+  // OnHpackFragment method.
+  DecodeStatus Decode(DecodeBuffer* db);
+
+  std::string DebugString() const;
+
+ private:
+  HpackEntryDecoder entry_decoder_;
+  HpackEntryDecoderListener* listener_;
+  bool before_entry_ = true;
+
+  DISALLOW_COPY_AND_ASSIGN(HpackBlockDecoder);
+};
+
+NET_EXPORT_PRIVATE std::ostream& operator<<(std::ostream& out,
+                                            const HpackBlockDecoder& v);
+
+}  // namespace net
+
+#endif  // NET_HTTP2_HPACK_DECODER_HPACK_BLOCK_DECODER_H_