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

net/http2/hpack/decoder/hpack_entry_decoder_listener.h

Index: net/http2/hpack/decoder/hpack_entry_decoder_listener.h
diff --git a/net/http2/hpack/decoder/hpack_entry_decoder_listener.h b/net/http2/hpack/decoder/hpack_entry_decoder_listener.h
new file mode 100644
index 0000000000000000000000000000000000000000..09fbd5432f018b7b3ea3310a812af951ffcf3664
--- /dev/null
+++ b/net/http2/hpack/decoder/hpack_entry_decoder_listener.h
@@ -0,0 +1,110 @@
+// 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_ENTRY_DECODER_LISTENER_H_
+#define NET_HTTP2_HPACK_DECODER_HPACK_ENTRY_DECODER_LISTENER_H_
+
+// Defines HpackEntryDecoderListener, the base class of listeners that
+// HpackEntryDecoder calls. Also defines HpackEntryDecoderVLoggingListener
+// which logs before calling another HpackEntryDecoderListener implementation.
+
+#include <stddef.h>
+
+#include "net/base/net_export.h"
+#include "net/http2/hpack/http2_hpack_constants.h"
+
+namespace net {
+
+class NET_EXPORT_PRIVATE HpackEntryDecoderListener {
+ public:
+  virtual ~HpackEntryDecoderListener() {}
+
+  // Called when an indexed header (i.e. one in the static or dynamic table) has
+  // been decoded from an HPACK block. index is supposed to be non-zero, but
+  // that has not been checked by the caller.
+  virtual void OnIndexedHeader(size_t index) = 0;
+
+  // Called when the start of a header with a literal value, and maybe a literal
+  // name, has been decoded. maybe_name_index is zero if the header has a
+  // literal name, else it is a reference into the static or dynamic table, from
+  // which the name should be determined. When the name is literal, the next
+  // call will be to OnNameStart; else it will be to OnValueStart. entry_type
+  // indicates whether the peer has added the entry to its dynamic table, and
+  // whether a proxy is permitted to do so when forwarding the entry.
+  virtual void OnStartLiteralHeader(HpackEntryType entry_type,
+                                    size_t maybe_name_index) = 0;
+
+  // Called when the encoding (Huffman compressed or plain text) and the encoded
+  // length of a literal name has been decoded. OnNameData will be called next,
+  // and repeatedly until the sum of lengths passed to OnNameData is len.
+  virtual void OnNameStart(bool huffman_encoded, size_t len) = 0;
+
+  // Called when len bytes of an encoded header name have been decoded.
+  virtual void OnNameData(const char* data, size_t len) = 0;
+
+  // Called after the entire name has been passed to OnNameData.
+  // OnValueStart will be called next.
+  virtual void OnNameEnd() = 0;
+
+  // Called when the encoding (Huffman compressed or plain text) and the encoded
+  // length of a literal value has been decoded. OnValueData will be called
+  // next, and repeatedly until the sum of lengths passed to OnValueData is len.
+  virtual void OnValueStart(bool huffman_encoded, size_t len) = 0;
+
+  // Called when len bytes of an encoded header value have been decoded.
+  virtual void OnValueData(const char* data, size_t len) = 0;
+
+  // Called after the entire value has been passed to OnValueData, marking the
+  // end of a header entry with a literal value, and maybe a literal name.
+  virtual void OnValueEnd() = 0;
+
+  // Called when an update to the size of the peer's dynamic table has been
+  // decoded.
+  virtual void OnDynamicTableSizeUpdate(size_t size) = 0;
+};
+
+class NET_EXPORT_PRIVATE HpackEntryDecoderVLoggingListener
+    : public HpackEntryDecoderListener {
+ public:
+  HpackEntryDecoderVLoggingListener() : wrapped_(nullptr) {}
+  explicit HpackEntryDecoderVLoggingListener(HpackEntryDecoderListener* wrapped)
+      : wrapped_(wrapped) {}
+  ~HpackEntryDecoderVLoggingListener() override {}
+
+  void OnIndexedHeader(size_t index) override;
+  void OnStartLiteralHeader(HpackEntryType entry_type,
+                            size_t maybe_name_index) override;
+  void OnNameStart(bool huffman_encoded, size_t len) override;
+  void OnNameData(const char* data, size_t len) override;
+  void OnNameEnd() override;
+  void OnValueStart(bool huffman_encoded, size_t len) override;
+  void OnValueData(const char* data, size_t len) override;
+  void OnValueEnd() override;
+  void OnDynamicTableSizeUpdate(size_t size) override;
+
+ private:
+  HpackEntryDecoderListener* const wrapped_;
+};
+
+// A no-op implementation of HpackEntryDecoderListener.
+class NET_EXPORT_PRIVATE HpackEntryDecoderNoOpListener
+    : public HpackEntryDecoderListener {
+ public:
+  ~HpackEntryDecoderNoOpListener() override {}
+
+  void OnIndexedHeader(size_t index) override {}
+  void OnStartLiteralHeader(HpackEntryType entry_type,
+                            size_t maybe_name_index) override {}
+  void OnNameStart(bool huffman_encoded, size_t len) override {}
+  void OnNameData(const char* data, size_t len) override {}
+  void OnNameEnd() override {}
+  void OnValueStart(bool huffman_encoded, size_t len) override {}
+  void OnValueData(const char* data, size_t len) override {}
+  void OnValueEnd() override {}
+  void OnDynamicTableSizeUpdate(size_t size) override {}
+};
+
+}  // namespace net
+
+#endif  // NET_HTTP2_HPACK_DECODER_HPACK_ENTRY_DECODER_LISTENER_H_