From: =?UTF-8?q?Lo=C3=AFc=20Hoguin?= <essen@ninenines.eu>
Date: Thu, 19 Mar 2015 16:07:25 +0100
Subject: [PATCH] Add HPACK decoding and encoding functions

No decoding options have been added in this commit. They will be
added in the future.

Only one encoding option has been added: #{huffman => boolean()}.
It allows to disable Huffman compression of strings. This compression
is enabled by default.

diff --git a/src/cow_hpack.erl b/src/cow_hpack.erl
new file mode 100644
index 0000000..efabaa6
--- /dev/null
+++ b/src/cow_hpack.erl
@@ -0,0 +1,1288 @@
+%% Copyright (c) 2015, Loïc Hoguin <essen@ninenines.eu>
+%%
+%% Permission to use, copy, modify, and/or distribute this software for any
+%% purpose with or without fee is hereby granted, provided that the above
+%% copyright notice and this permission notice appear in all copies.
+%%
+%% THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+%% WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+%% MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+%% ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+%% WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+%% ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+%% OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+
+%% The current implementation is not suitable for use in
+%% intermediaries as the information about headers that
+%% should never be indexed is currently lost.
+
+-module(cow_hpack).
+
+-export([init/0]).
+-export([init/1]).
+
+-export([decode/1]).
+-export([decode/2]).
+-export([decode/3]).
+
+-export([encode/1]).
+-export([encode/2]).
+-export([encode/3]).
+
+-record(state, {
+	size = 0 :: non_neg_integer(),
+	max_size = 4096 :: non_neg_integer(),
+	dyn_table = [] :: queue:queue({binary(), binary()})
+}).
+
+-opaque state() :: #state{}.
+-export_type([state/0]).
+
+-type opts() :: map().
+-export_type([opts/0]).
+
+-ifdef(TEST).
+-include_lib("triq/include/triq.hrl").
+-endif.
+
+%% State initialization.
+
+-spec init() -> state().
+init() ->
+	#state{}.
+
+-spec init(non_neg_integer()) -> state().
+init(MaxSize) ->
+	#state{max_size=MaxSize}.
+
+%% Decoding.
+
+-spec decode(binary()) -> {cow_http:headers(), state()}.
+decode(Data) ->
+	decode(Data, init(), #{}).
+
+-spec decode(binary(), State) -> {cow_http:headers(), State} when State::state().
+decode(Data, State) ->
+	decode(Data, State, #{}).
+
+-spec decode(binary(), State, opts()) -> {cow_http:headers(), State} when State::state().
+decode(Data, State, Opts) ->
+	decode(Data, State, Opts, []).
+
+decode(<<>>, State, _, Acc) ->
+	{lists:reverse(Acc), State};
+%% Indexed header field representation.
+decode(<< 1:1, Rest/bits >>, State, Opts, Acc) ->
+	dec_indexed(Rest, State, Opts, Acc);
+%% Literal header field with incremental indexing: new name.
+decode(<< 0:1, 1:1, 0:6, Rest/bits >>, State, Opts, Acc) ->
+	dec_lit_index_new_name(Rest, State, Opts, Acc);
+%% Literal header field with incremental indexing: indexed name.
+decode(<< 0:1, 1:1, Rest/bits >>, State, Opts, Acc) ->
+	dec_lit_index_indexed_name(Rest, State, Opts, Acc);
+%% Literal header field without indexing: new name.
+decode(<< 0:8, Rest/bits >>, State, Opts, Acc) ->
+	dec_lit_no_index_new_name(Rest, State, Opts, Acc);
+%% Literal header field without indexing: indexed name.
+decode(<< 0:4, Rest/bits >>, State, Opts, Acc) ->
+	dec_lit_no_index_indexed_name(Rest, State, Opts, Acc);
+%% Literal header field never indexed: new name.
+%% @todo Keep track of "never indexed" headers.
+decode(<< 0:3, 1:1, 0:4, Rest/bits >>, State, Opts, Acc) ->
+	dec_lit_no_index_new_name(Rest, State, Opts, Acc);
+%% Literal header field never indexed: indexed name.
+%% @todo Keep track of "never indexed" headers.
+decode(<< 0:3, 1:1, Rest/bits >>, State, Opts, Acc) ->
+	dec_lit_no_index_indexed_name(Rest, State, Opts, Acc);
+%% Dynamic table size update.
+decode(<< 0:2, 1:1, Rest/bits >>, State, Opts, Acc) ->
+	dec_table_size_update(Rest, State, Opts, Acc).
+
+%% Indexed header field representation.
+
+dec_indexed(Rest, State, Opts, Acc) ->
+	{Index, Rest2} = dec_int7(Rest),
+	{Name, Value} = table_get(Index, State),
+	decode(Rest2, State, Opts, [{Name, Value}|Acc]).
+
+%% Literal header field with incremental indexing.
+
+dec_lit_index_new_name(Rest, State, Opts, Acc) ->
+	{Name, Rest2} = dec_str(Rest),
+	dec_lit_index(Rest2, State, Opts, Acc, Name).
+
+dec_lit_index_indexed_name(Rest, State, Opts, Acc) ->
+	{Index, Rest2} = dec_int6(Rest),
+	Name = table_get_name(Index, State),
+	dec_lit_index(Rest2, State, Opts, Acc, Name).
+
+dec_lit_index(Rest, State, Opts, Acc, Name) ->
+	{Value, Rest2} = dec_str(Rest),
+	State2 = table_insert({Name, Value}, State),
+	decode(Rest2, State2, Opts, [{Name, Value}|Acc]).
+
+%% Literal header field without indexing.
+
+dec_lit_no_index_new_name(Rest, State, Opts, Acc) ->
+	{Name, Rest2} = dec_str(Rest),
+	dec_lit_no_index(Rest2, State, Opts, Acc, Name).
+
+dec_lit_no_index_indexed_name(Rest, State, Opts, Acc) ->
+	{Index, Rest2} = dec_int4(Rest),
+	Name = table_get_name(Index, State),
+	dec_lit_no_index(Rest2, State, Opts, Acc, Name).
+
+dec_lit_no_index(Rest, State, Opts, Acc, Name) ->
+	{Value, Rest2} = dec_str(Rest),
+	decode(Rest2, State, Opts, [{Name, Value}|Acc]).
+
+%% @todo Literal header field never indexed.
+
+%% Dynamic table size update.
+
+dec_table_size_update(Rest, State, Opts, Acc) ->
+	{MaxSize, Rest2} = dec_int5(Rest),
+	State2 = table_update_size(MaxSize, State),
+	decode(Rest2, State2, Opts, Acc).
+
+%% Decode an integer.
+
+%% The HPACK format has 4 different integer prefixes length (from 4 to 7)
+%% and each can be used to create an indefinite length integer if all bits
+%% of the prefix are set to 1.
+
+dec_int4(<< 2#1111:4, Rest/bits >>) ->
+	dec_big_int(Rest, 15, 0);
+dec_int4(<< Int:4, Rest/bits >>) ->
+	{Int, Rest}.
+
+dec_int5(<< 2#11111:5, Rest/bits >>) ->
+	dec_big_int(Rest, 31, 0);
+dec_int5(<< Int:5, Rest/bits >>) ->
+	{Int, Rest}.
+
+dec_int6(<< 2#111111:6, Rest/bits >>) ->
+	dec_big_int(Rest, 63, 0);
+dec_int6(<< Int:6, Rest/bits >>) ->
+	{Int, Rest}.
+
+dec_int7(<< 2#1111111:7, Rest/bits >>) ->
+	dec_big_int(Rest, 127, 0);
+dec_int7(<< Int:7, Rest/bits >>) ->
+	{Int, Rest}.
+
+dec_big_int(<< 0:1, Value:7, Rest/bits >>, Int, M) ->
+	{Int + (Value bsl M), Rest};
+dec_big_int(<< 1:1, Value:7, Rest/bits >>, Int, M) ->
+	dec_big_int(Rest, Int + (Value bsl M), M + 7).
+
+%% Decode a string.
+
+dec_str(<< 0:1, Rest/bits >>) ->
+	{Length, Rest2} = dec_int7(Rest),
+	<< Str:Length/binary, Rest3/bits >> = Rest2,
+	{Str, Rest3};
+dec_str(<< 1:1, Rest/bits >>) ->
+	{Length, Rest2} = dec_int7(Rest),
+	dec_huffman(Rest2, Length * 8, <<>>).
+
+%% HPACK uses a static code table for Huffman encoded strings.
+%% It has been converted into one clause per code in the following function.
+
+%% EOS.
+dec_huffman(Rest, 0, String) -> {String, Rest};
+dec_huffman(<<2#1:1, Rest/bits>>, 1, String) -> {String, Rest};
+dec_huffman(<<2#11:2, Rest/bits>>, 2, String) -> {String, Rest};
+dec_huffman(<<2#111:3, Rest/bits>>, 3, String) -> {String, Rest};
+dec_huffman(<<2#1111:4, Rest/bits>>, 4, String) -> {String, Rest};
+dec_huffman(<<2#11111:5, Rest/bits>>, 5, String) -> {String, Rest};
+dec_huffman(<<2#111111:6, Rest/bits>>, 6, String) -> {String, Rest};
+dec_huffman(<<2#1111111:7, Rest/bits>>, 7, String) -> {String, Rest};
+%% Static code table.
+dec_huffman(<<2#00000:5, R/bits>>, L, A) -> dec_huffman(R, L - 5, <<A/binary, 48>>);
+dec_huffman(<<2#00001:5, R/bits>>, L, A) -> dec_huffman(R, L - 5, <<A/binary, 49>>);
+dec_huffman(<<2#00010:5, R/bits>>, L, A) -> dec_huffman(R, L - 5, <<A/binary, 50>>);
+dec_huffman(<<2#00011:5, R/bits>>, L, A) -> dec_huffman(R, L - 5, <<A/binary, 97>>);
+dec_huffman(<<2#00100:5, R/bits>>, L, A) -> dec_huffman(R, L - 5, <<A/binary, 99>>);
+dec_huffman(<<2#00101:5, R/bits>>, L, A) -> dec_huffman(R, L - 5, <<A/binary, 101>>);
+dec_huffman(<<2#00110:5, R/bits>>, L, A) -> dec_huffman(R, L - 5, <<A/binary, 105>>);
+dec_huffman(<<2#00111:5, R/bits>>, L, A) -> dec_huffman(R, L - 5, <<A/binary, 111>>);
+dec_huffman(<<2#01000:5, R/bits>>, L, A) -> dec_huffman(R, L - 5, <<A/binary, 115>>);
+dec_huffman(<<2#01001:5, R/bits>>, L, A) -> dec_huffman(R, L - 5, <<A/binary, 116>>);
+dec_huffman(<<2#010100:6, R/bits>>, L, A) -> dec_huffman(R, L - 6, <<A/binary, 32>>);
+dec_huffman(<<2#010101:6, R/bits>>, L, A) -> dec_huffman(R, L - 6, <<A/binary, 37>>);
+dec_huffman(<<2#010110:6, R/bits>>, L, A) -> dec_huffman(R, L - 6, <<A/binary, 45>>);
+dec_huffman(<<2#010111:6, R/bits>>, L, A) -> dec_huffman(R, L - 6, <<A/binary, 46>>);
+dec_huffman(<<2#011000:6, R/bits>>, L, A) -> dec_huffman(R, L - 6, <<A/binary, 47>>);
+dec_huffman(<<2#011001:6, R/bits>>, L, A) -> dec_huffman(R, L - 6, <<A/binary, 51>>);
+dec_huffman(<<2#011010:6, R/bits>>, L, A) -> dec_huffman(R, L - 6, <<A/binary, 52>>);
+dec_huffman(<<2#011011:6, R/bits>>, L, A) -> dec_huffman(R, L - 6, <<A/binary, 53>>);
+dec_huffman(<<2#011100:6, R/bits>>, L, A) -> dec_huffman(R, L - 6, <<A/binary, 54>>);
+dec_huffman(<<2#011101:6, R/bits>>, L, A) -> dec_huffman(R, L - 6, <<A/binary, 55>>);
+dec_huffman(<<2#011110:6, R/bits>>, L, A) -> dec_huffman(R, L - 6, <<A/binary, 56>>);
+dec_huffman(<<2#011111:6, R/bits>>, L, A) -> dec_huffman(R, L - 6, <<A/binary, 57>>);
+dec_huffman(<<2#100000:6, R/bits>>, L, A) -> dec_huffman(R, L - 6, <<A/binary, 61>>);
+dec_huffman(<<2#100001:6, R/bits>>, L, A) -> dec_huffman(R, L - 6, <<A/binary, 65>>);
+dec_huffman(<<2#100010:6, R/bits>>, L, A) -> dec_huffman(R, L - 6, <<A/binary, 95>>);
+dec_huffman(<<2#100011:6, R/bits>>, L, A) -> dec_huffman(R, L - 6, <<A/binary, 98>>);
+dec_huffman(<<2#100100:6, R/bits>>, L, A) -> dec_huffman(R, L - 6, <<A/binary, 100>>);
+dec_huffman(<<2#100101:6, R/bits>>, L, A) -> dec_huffman(R, L - 6, <<A/binary, 102>>);
+dec_huffman(<<2#100110:6, R/bits>>, L, A) -> dec_huffman(R, L - 6, <<A/binary, 103>>);
+dec_huffman(<<2#100111:6, R/bits>>, L, A) -> dec_huffman(R, L - 6, <<A/binary, 104>>);
+dec_huffman(<<2#101000:6, R/bits>>, L, A) -> dec_huffman(R, L - 6, <<A/binary, 108>>);
+dec_huffman(<<2#101001:6, R/bits>>, L, A) -> dec_huffman(R, L - 6, <<A/binary, 109>>);
+dec_huffman(<<2#101010:6, R/bits>>, L, A) -> dec_huffman(R, L - 6, <<A/binary, 110>>);
+dec_huffman(<<2#101011:6, R/bits>>, L, A) -> dec_huffman(R, L - 6, <<A/binary, 112>>);
+dec_huffman(<<2#101100:6, R/bits>>, L, A) -> dec_huffman(R, L - 6, <<A/binary, 114>>);
+dec_huffman(<<2#101101:6, R/bits>>, L, A) -> dec_huffman(R, L - 6, <<A/binary, 117>>);
+dec_huffman(<<2#1011100:7, R/bits>>, L, A) -> dec_huffman(R, L - 7, <<A/binary, 58>>);
+dec_huffman(<<2#1011101:7, R/bits>>, L, A) -> dec_huffman(R, L - 7, <<A/binary, 66>>);
+dec_huffman(<<2#1011110:7, R/bits>>, L, A) -> dec_huffman(R, L - 7, <<A/binary, 67>>);
+dec_huffman(<<2#1011111:7, R/bits>>, L, A) -> dec_huffman(R, L - 7, <<A/binary, 68>>);
+dec_huffman(<<2#1100000:7, R/bits>>, L, A) -> dec_huffman(R, L - 7, <<A/binary, 69>>);
+dec_huffman(<<2#1100001:7, R/bits>>, L, A) -> dec_huffman(R, L - 7, <<A/binary, 70>>);
+dec_huffman(<<2#1100010:7, R/bits>>, L, A) -> dec_huffman(R, L - 7, <<A/binary, 71>>);
+dec_huffman(<<2#1100011:7, R/bits>>, L, A) -> dec_huffman(R, L - 7, <<A/binary, 72>>);
+dec_huffman(<<2#1100100:7, R/bits>>, L, A) -> dec_huffman(R, L - 7, <<A/binary, 73>>);
+dec_huffman(<<2#1100101:7, R/bits>>, L, A) -> dec_huffman(R, L - 7, <<A/binary, 74>>);
+dec_huffman(<<2#1100110:7, R/bits>>, L, A) -> dec_huffman(R, L - 7, <<A/binary, 75>>);
+dec_huffman(<<2#1100111:7, R/bits>>, L, A) -> dec_huffman(R, L - 7, <<A/binary, 76>>);
+dec_huffman(<<2#1101000:7, R/bits>>, L, A) -> dec_huffman(R, L - 7, <<A/binary, 77>>);
+dec_huffman(<<2#1101001:7, R/bits>>, L, A) -> dec_huffman(R, L - 7, <<A/binary, 78>>);
+dec_huffman(<<2#1101010:7, R/bits>>, L, A) -> dec_huffman(R, L - 7, <<A/binary, 79>>);
+dec_huffman(<<2#1101011:7, R/bits>>, L, A) -> dec_huffman(R, L - 7, <<A/binary, 80>>);
+dec_huffman(<<2#1101100:7, R/bits>>, L, A) -> dec_huffman(R, L - 7, <<A/binary, 81>>);
+dec_huffman(<<2#1101101:7, R/bits>>, L, A) -> dec_huffman(R, L - 7, <<A/binary, 82>>);
+dec_huffman(<<2#1101110:7, R/bits>>, L, A) -> dec_huffman(R, L - 7, <<A/binary, 83>>);
+dec_huffman(<<2#1101111:7, R/bits>>, L, A) -> dec_huffman(R, L - 7, <<A/binary, 84>>);
+dec_huffman(<<2#1110000:7, R/bits>>, L, A) -> dec_huffman(R, L - 7, <<A/binary, 85>>);
+dec_huffman(<<2#1110001:7, R/bits>>, L, A) -> dec_huffman(R, L - 7, <<A/binary, 86>>);
+dec_huffman(<<2#1110010:7, R/bits>>, L, A) -> dec_huffman(R, L - 7, <<A/binary, 87>>);
+dec_huffman(<<2#1110011:7, R/bits>>, L, A) -> dec_huffman(R, L - 7, <<A/binary, 89>>);
+dec_huffman(<<2#1110100:7, R/bits>>, L, A) -> dec_huffman(R, L - 7, <<A/binary, 106>>);
+dec_huffman(<<2#1110101:7, R/bits>>, L, A) -> dec_huffman(R, L - 7, <<A/binary, 107>>);
+dec_huffman(<<2#1110110:7, R/bits>>, L, A) -> dec_huffman(R, L - 7, <<A/binary, 113>>);
+dec_huffman(<<2#1110111:7, R/bits>>, L, A) -> dec_huffman(R, L - 7, <<A/binary, 118>>);
+dec_huffman(<<2#1111000:7, R/bits>>, L, A) -> dec_huffman(R, L - 7, <<A/binary, 119>>);
+dec_huffman(<<2#1111001:7, R/bits>>, L, A) -> dec_huffman(R, L - 7, <<A/binary, 120>>);
+dec_huffman(<<2#1111010:7, R/bits>>, L, A) -> dec_huffman(R, L - 7, <<A/binary, 121>>);
+dec_huffman(<<2#1111011:7, R/bits>>, L, A) -> dec_huffman(R, L - 7, <<A/binary, 122>>);
+dec_huffman(<<2#11111000:8, R/bits>>, L, A) -> dec_huffman(R, L - 8, <<A/binary, 38>>);
+dec_huffman(<<2#11111001:8, R/bits>>, L, A) -> dec_huffman(R, L - 8, <<A/binary, 42>>);
+dec_huffman(<<2#11111010:8, R/bits>>, L, A) -> dec_huffman(R, L - 8, <<A/binary, 44>>);
+dec_huffman(<<2#11111011:8, R/bits>>, L, A) -> dec_huffman(R, L - 8, <<A/binary, 59>>);
+dec_huffman(<<2#11111100:8, R/bits>>, L, A) -> dec_huffman(R, L - 8, <<A/binary, 88>>);
+dec_huffman(<<2#11111101:8, R/bits>>, L, A) -> dec_huffman(R, L - 8, <<A/binary, 90>>);
+dec_huffman(<<2#1111111000:10, R/bits>>, L, A) -> dec_huffman(R, L - 10, <<A/binary, 33>>);
+dec_huffman(<<2#1111111001:10, R/bits>>, L, A) -> dec_huffman(R, L - 10, <<A/binary, 34>>);
+dec_huffman(<<2#1111111010:10, R/bits>>, L, A) -> dec_huffman(R, L - 10, <<A/binary, 40>>);
+dec_huffman(<<2#1111111011:10, R/bits>>, L, A) -> dec_huffman(R, L - 10, <<A/binary, 41>>);
+dec_huffman(<<2#1111111100:10, R/bits>>, L, A) -> dec_huffman(R, L - 10, <<A/binary, 63>>);
+dec_huffman(<<2#11111111010:11, R/bits>>, L, A) -> dec_huffman(R, L - 11, <<A/binary, 39>>);
+dec_huffman(<<2#11111111011:11, R/bits>>, L, A) -> dec_huffman(R, L - 11, <<A/binary, 43>>);
+dec_huffman(<<2#11111111100:11, R/bits>>, L, A) -> dec_huffman(R, L - 11, <<A/binary, 124>>);
+dec_huffman(<<2#111111111010:12, R/bits>>, L, A) -> dec_huffman(R, L - 12, <<A/binary, 35>>);
+dec_huffman(<<2#111111111011:12, R/bits>>, L, A) -> dec_huffman(R, L - 12, <<A/binary, 62>>);
+dec_huffman(<<2#1111111111000:13, R/bits>>, L, A) -> dec_huffman(R, L - 13, <<A/binary, 0>>);
+dec_huffman(<<2#1111111111001:13, R/bits>>, L, A) -> dec_huffman(R, L - 13, <<A/binary, 36>>);
+dec_huffman(<<2#1111111111010:13, R/bits>>, L, A) -> dec_huffman(R, L - 13, <<A/binary, 64>>);
+dec_huffman(<<2#1111111111011:13, R/bits>>, L, A) -> dec_huffman(R, L - 13, <<A/binary, 91>>);
+dec_huffman(<<2#1111111111100:13, R/bits>>, L, A) -> dec_huffman(R, L - 13, <<A/binary, 93>>);
+dec_huffman(<<2#1111111111101:13, R/bits>>, L, A) -> dec_huffman(R, L - 13, <<A/binary, 126>>);
+dec_huffman(<<2#11111111111100:14, R/bits>>, L, A) -> dec_huffman(R, L - 14, <<A/binary, 94>>);
+dec_huffman(<<2#11111111111101:14, R/bits>>, L, A) -> dec_huffman(R, L - 14, <<A/binary, 125>>);
+dec_huffman(<<2#111111111111100:15, R/bits>>, L, A) -> dec_huffman(R, L - 15, <<A/binary, 60>>);
+dec_huffman(<<2#111111111111101:15, R/bits>>, L, A) -> dec_huffman(R, L - 15, <<A/binary, 96>>);
+dec_huffman(<<2#111111111111110:15, R/bits>>, L, A) -> dec_huffman(R, L - 15, <<A/binary, 123>>);
+dec_huffman(<<2#1111111111111110000:19, R/bits>>, L, A) -> dec_huffman(R, L - 19, <<A/binary, 92>>);
+dec_huffman(<<2#1111111111111110001:19, R/bits>>, L, A) -> dec_huffman(R, L - 19, <<A/binary, 195>>);
+dec_huffman(<<2#1111111111111110010:19, R/bits>>, L, A) -> dec_huffman(R, L - 19, <<A/binary, 208>>);
+dec_huffman(<<2#11111111111111100110:20, R/bits>>, L, A) -> dec_huffman(R, L - 20, <<A/binary, 128>>);
+dec_huffman(<<2#11111111111111100111:20, R/bits>>, L, A) -> dec_huffman(R, L - 20, <<A/binary, 130>>);
+dec_huffman(<<2#11111111111111101000:20, R/bits>>, L, A) -> dec_huffman(R, L - 20, <<A/binary, 131>>);
+dec_huffman(<<2#11111111111111101001:20, R/bits>>, L, A) -> dec_huffman(R, L - 20, <<A/binary, 162>>);
+dec_huffman(<<2#11111111111111101010:20, R/bits>>, L, A) -> dec_huffman(R, L - 20, <<A/binary, 184>>);
+dec_huffman(<<2#11111111111111101011:20, R/bits>>, L, A) -> dec_huffman(R, L - 20, <<A/binary, 194>>);
+dec_huffman(<<2#11111111111111101100:20, R/bits>>, L, A) -> dec_huffman(R, L - 20, <<A/binary, 224>>);
+dec_huffman(<<2#11111111111111101101:20, R/bits>>, L, A) -> dec_huffman(R, L - 20, <<A/binary, 226>>);
+dec_huffman(<<2#111111111111111011100:21, R/bits>>, L, A) -> dec_huffman(R, L - 21, <<A/binary, 153>>);
+dec_huffman(<<2#111111111111111011101:21, R/bits>>, L, A) -> dec_huffman(R, L - 21, <<A/binary, 161>>);
+dec_huffman(<<2#111111111111111011110:21, R/bits>>, L, A) -> dec_huffman(R, L - 21, <<A/binary, 167>>);
+dec_huffman(<<2#111111111111111011111:21, R/bits>>, L, A) -> dec_huffman(R, L - 21, <<A/binary, 172>>);
+dec_huffman(<<2#111111111111111100000:21, R/bits>>, L, A) -> dec_huffman(R, L - 21, <<A/binary, 176>>);
+dec_huffman(<<2#111111111111111100001:21, R/bits>>, L, A) -> dec_huffman(R, L - 21, <<A/binary, 177>>);
+dec_huffman(<<2#111111111111111100010:21, R/bits>>, L, A) -> dec_huffman(R, L - 21, <<A/binary, 179>>);
+dec_huffman(<<2#111111111111111100011:21, R/bits>>, L, A) -> dec_huffman(R, L - 21, <<A/binary, 209>>);
+dec_huffman(<<2#111111111111111100100:21, R/bits>>, L, A) -> dec_huffman(R, L - 21, <<A/binary, 216>>);
+dec_huffman(<<2#111111111111111100101:21, R/bits>>, L, A) -> dec_huffman(R, L - 21, <<A/binary, 217>>);
+dec_huffman(<<2#111111111111111100110:21, R/bits>>, L, A) -> dec_huffman(R, L - 21, <<A/binary, 227>>);
+dec_huffman(<<2#111111111111111100111:21, R/bits>>, L, A) -> dec_huffman(R, L - 21, <<A/binary, 229>>);
+dec_huffman(<<2#111111111111111101000:21, R/bits>>, L, A) -> dec_huffman(R, L - 21, <<A/binary, 230>>);
+dec_huffman(<<2#1111111111111111010010:22, R/bits>>, L, A) -> dec_huffman(R, L - 22, <<A/binary, 129>>);
+dec_huffman(<<2#1111111111111111010011:22, R/bits>>, L, A) -> dec_huffman(R, L - 22, <<A/binary, 132>>);
+dec_huffman(<<2#1111111111111111010100:22, R/bits>>, L, A) -> dec_huffman(R, L - 22, <<A/binary, 133>>);
+dec_huffman(<<2#1111111111111111010101:22, R/bits>>, L, A) -> dec_huffman(R, L - 22, <<A/binary, 134>>);
+dec_huffman(<<2#1111111111111111010110:22, R/bits>>, L, A) -> dec_huffman(R, L - 22, <<A/binary, 136>>);
+dec_huffman(<<2#1111111111111111010111:22, R/bits>>, L, A) -> dec_huffman(R, L - 22, <<A/binary, 146>>);
+dec_huffman(<<2#1111111111111111011000:22, R/bits>>, L, A) -> dec_huffman(R, L - 22, <<A/binary, 154>>);
+dec_huffman(<<2#1111111111111111011001:22, R/bits>>, L, A) -> dec_huffman(R, L - 22, <<A/binary, 156>>);
+dec_huffman(<<2#1111111111111111011010:22, R/bits>>, L, A) -> dec_huffman(R, L - 22, <<A/binary, 160>>);
+dec_huffman(<<2#1111111111111111011011:22, R/bits>>, L, A) -> dec_huffman(R, L - 22, <<A/binary, 163>>);
+dec_huffman(<<2#1111111111111111011100:22, R/bits>>, L, A) -> dec_huffman(R, L - 22, <<A/binary, 164>>);
+dec_huffman(<<2#1111111111111111011101:22, R/bits>>, L, A) -> dec_huffman(R, L - 22, <<A/binary, 169>>);
+dec_huffman(<<2#1111111111111111011110:22, R/bits>>, L, A) -> dec_huffman(R, L - 22, <<A/binary, 170>>);
+dec_huffman(<<2#1111111111111111011111:22, R/bits>>, L, A) -> dec_huffman(R, L - 22, <<A/binary, 173>>);
+dec_huffman(<<2#1111111111111111100000:22, R/bits>>, L, A) -> dec_huffman(R, L - 22, <<A/binary, 178>>);
+dec_huffman(<<2#1111111111111111100001:22, R/bits>>, L, A) -> dec_huffman(R, L - 22, <<A/binary, 181>>);
+dec_huffman(<<2#1111111111111111100010:22, R/bits>>, L, A) -> dec_huffman(R, L - 22, <<A/binary, 185>>);
+dec_huffman(<<2#1111111111111111100011:22, R/bits>>, L, A) -> dec_huffman(R, L - 22, <<A/binary, 186>>);
+dec_huffman(<<2#1111111111111111100100:22, R/bits>>, L, A) -> dec_huffman(R, L - 22, <<A/binary, 187>>);
+dec_huffman(<<2#1111111111111111100101:22, R/bits>>, L, A) -> dec_huffman(R, L - 22, <<A/binary, 189>>);
+dec_huffman(<<2#1111111111111111100110:22, R/bits>>, L, A) -> dec_huffman(R, L - 22, <<A/binary, 190>>);
+dec_huffman(<<2#1111111111111111100111:22, R/bits>>, L, A) -> dec_huffman(R, L - 22, <<A/binary, 196>>);
+dec_huffman(<<2#1111111111111111101000:22, R/bits>>, L, A) -> dec_huffman(R, L - 22, <<A/binary, 198>>);
+dec_huffman(<<2#1111111111111111101001:22, R/bits>>, L, A) -> dec_huffman(R, L - 22, <<A/binary, 228>>);
+dec_huffman(<<2#1111111111111111101010:22, R/bits>>, L, A) -> dec_huffman(R, L - 22, <<A/binary, 232>>);
+dec_huffman(<<2#1111111111111111101011:22, R/bits>>, L, A) -> dec_huffman(R, L - 22, <<A/binary, 233>>);
+dec_huffman(<<2#11111111111111111011000:23, R/bits>>, L, A) -> dec_huffman(R, L - 23, <<A/binary, 1>>);
+dec_huffman(<<2#11111111111111111011001:23, R/bits>>, L, A) -> dec_huffman(R, L - 23, <<A/binary, 135>>);
+dec_huffman(<<2#11111111111111111011010:23, R/bits>>, L, A) -> dec_huffman(R, L - 23, <<A/binary, 137>>);
+dec_huffman(<<2#11111111111111111011011:23, R/bits>>, L, A) -> dec_huffman(R, L - 23, <<A/binary, 138>>);
+dec_huffman(<<2#11111111111111111011100:23, R/bits>>, L, A) -> dec_huffman(R, L - 23, <<A/binary, 139>>);
+dec_huffman(<<2#11111111111111111011101:23, R/bits>>, L, A) -> dec_huffman(R, L - 23, <<A/binary, 140>>);
+dec_huffman(<<2#11111111111111111011110:23, R/bits>>, L, A) -> dec_huffman(R, L - 23, <<A/binary, 141>>);
+dec_huffman(<<2#11111111111111111011111:23, R/bits>>, L, A) -> dec_huffman(R, L - 23, <<A/binary, 143>>);
+dec_huffman(<<2#11111111111111111100000:23, R/bits>>, L, A) -> dec_huffman(R, L - 23, <<A/binary, 147>>);
+dec_huffman(<<2#11111111111111111100001:23, R/bits>>, L, A) -> dec_huffman(R, L - 23, <<A/binary, 149>>);
+dec_huffman(<<2#11111111111111111100010:23, R/bits>>, L, A) -> dec_huffman(R, L - 23, <<A/binary, 150>>);
+dec_huffman(<<2#11111111111111111100011:23, R/bits>>, L, A) -> dec_huffman(R, L - 23, <<A/binary, 151>>);
+dec_huffman(<<2#11111111111111111100100:23, R/bits>>, L, A) -> dec_huffman(R, L - 23, <<A/binary, 152>>);
+dec_huffman(<<2#11111111111111111100101:23, R/bits>>, L, A) -> dec_huffman(R, L - 23, <<A/binary, 155>>);
+dec_huffman(<<2#11111111111111111100110:23, R/bits>>, L, A) -> dec_huffman(R, L - 23, <<A/binary, 157>>);
+dec_huffman(<<2#11111111111111111100111:23, R/bits>>, L, A) -> dec_huffman(R, L - 23, <<A/binary, 158>>);
+dec_huffman(<<2#11111111111111111101000:23, R/bits>>, L, A) -> dec_huffman(R, L - 23, <<A/binary, 165>>);
+dec_huffman(<<2#11111111111111111101001:23, R/bits>>, L, A) -> dec_huffman(R, L - 23, <<A/binary, 166>>);
+dec_huffman(<<2#11111111111111111101010:23, R/bits>>, L, A) -> dec_huffman(R, L - 23, <<A/binary, 168>>);
+dec_huffman(<<2#11111111111111111101011:23, R/bits>>, L, A) -> dec_huffman(R, L - 23, <<A/binary, 174>>);
+dec_huffman(<<2#11111111111111111101100:23, R/bits>>, L, A) -> dec_huffman(R, L - 23, <<A/binary, 175>>);
+dec_huffman(<<2#11111111111111111101101:23, R/bits>>, L, A) -> dec_huffman(R, L - 23, <<A/binary, 180>>);
+dec_huffman(<<2#11111111111111111101110:23, R/bits>>, L, A) -> dec_huffman(R, L - 23, <<A/binary, 182>>);
+dec_huffman(<<2#11111111111111111101111:23, R/bits>>, L, A) -> dec_huffman(R, L - 23, <<A/binary, 183>>);
+dec_huffman(<<2#11111111111111111110000:23, R/bits>>, L, A) -> dec_huffman(R, L - 23, <<A/binary, 188>>);
+dec_huffman(<<2#11111111111111111110001:23, R/bits>>, L, A) -> dec_huffman(R, L - 23, <<A/binary, 191>>);
+dec_huffman(<<2#11111111111111111110010:23, R/bits>>, L, A) -> dec_huffman(R, L - 23, <<A/binary, 197>>);
+dec_huffman(<<2#11111111111111111110011:23, R/bits>>, L, A) -> dec_huffman(R, L - 23, <<A/binary, 231>>);
+dec_huffman(<<2#11111111111111111110100:23, R/bits>>, L, A) -> dec_huffman(R, L - 23, <<A/binary, 239>>);
+dec_huffman(<<2#111111111111111111101010:24, R/bits>>, L, A) -> dec_huffman(R, L - 24, <<A/binary, 9>>);
+dec_huffman(<<2#111111111111111111101011:24, R/bits>>, L, A) -> dec_huffman(R, L - 24, <<A/binary, 142>>);
+dec_huffman(<<2#111111111111111111101100:24, R/bits>>, L, A) -> dec_huffman(R, L - 24, <<A/binary, 144>>);
+dec_huffman(<<2#111111111111111111101101:24, R/bits>>, L, A) -> dec_huffman(R, L - 24, <<A/binary, 145>>);
+dec_huffman(<<2#111111111111111111101110:24, R/bits>>, L, A) -> dec_huffman(R, L - 24, <<A/binary, 148>>);
+dec_huffman(<<2#111111111111111111101111:24, R/bits>>, L, A) -> dec_huffman(R, L - 24, <<A/binary, 159>>);
+dec_huffman(<<2#111111111111111111110000:24, R/bits>>, L, A) -> dec_huffman(R, L - 24, <<A/binary, 171>>);
+dec_huffman(<<2#111111111111111111110001:24, R/bits>>, L, A) -> dec_huffman(R, L - 24, <<A/binary, 206>>);
+dec_huffman(<<2#111111111111111111110010:24, R/bits>>, L, A) -> dec_huffman(R, L - 24, <<A/binary, 215>>);
+dec_huffman(<<2#111111111111111111110011:24, R/bits>>, L, A) -> dec_huffman(R, L - 24, <<A/binary, 225>>);
+dec_huffman(<<2#111111111111111111110100:24, R/bits>>, L, A) -> dec_huffman(R, L - 24, <<A/binary, 236>>);
+dec_huffman(<<2#111111111111111111110101:24, R/bits>>, L, A) -> dec_huffman(R, L - 24, <<A/binary, 237>>);
+dec_huffman(<<2#1111111111111111111101100:25, R/bits>>, L, A) -> dec_huffman(R, L - 25, <<A/binary, 199>>);
+dec_huffman(<<2#1111111111111111111101101:25, R/bits>>, L, A) -> dec_huffman(R, L - 25, <<A/binary, 207>>);
+dec_huffman(<<2#1111111111111111111101110:25, R/bits>>, L, A) -> dec_huffman(R, L - 25, <<A/binary, 234>>);
+dec_huffman(<<2#1111111111111111111101111:25, R/bits>>, L, A) -> dec_huffman(R, L - 25, <<A/binary, 235>>);
+dec_huffman(<<2#11111111111111111111100000:26, R/bits>>, L, A) -> dec_huffman(R, L - 26, <<A/binary, 192>>);
+dec_huffman(<<2#11111111111111111111100001:26, R/bits>>, L, A) -> dec_huffman(R, L - 26, <<A/binary, 193>>);
+dec_huffman(<<2#11111111111111111111100010:26, R/bits>>, L, A) -> dec_huffman(R, L - 26, <<A/binary, 200>>);
+dec_huffman(<<2#11111111111111111111100011:26, R/bits>>, L, A) -> dec_huffman(R, L - 26, <<A/binary, 201>>);
+dec_huffman(<<2#11111111111111111111100100:26, R/bits>>, L, A) -> dec_huffman(R, L - 26, <<A/binary, 202>>);
+dec_huffman(<<2#11111111111111111111100101:26, R/bits>>, L, A) -> dec_huffman(R, L - 26, <<A/binary, 205>>);
+dec_huffman(<<2#11111111111111111111100110:26, R/bits>>, L, A) -> dec_huffman(R, L - 26, <<A/binary, 210>>);
+dec_huffman(<<2#11111111111111111111100111:26, R/bits>>, L, A) -> dec_huffman(R, L - 26, <<A/binary, 213>>);
+dec_huffman(<<2#11111111111111111111101000:26, R/bits>>, L, A) -> dec_huffman(R, L - 26, <<A/binary, 218>>);
+dec_huffman(<<2#11111111111111111111101001:26, R/bits>>, L, A) -> dec_huffman(R, L - 26, <<A/binary, 219>>);
+dec_huffman(<<2#11111111111111111111101010:26, R/bits>>, L, A) -> dec_huffman(R, L - 26, <<A/binary, 238>>);
+dec_huffman(<<2#11111111111111111111101011:26, R/bits>>, L, A) -> dec_huffman(R, L - 26, <<A/binary, 240>>);
+dec_huffman(<<2#11111111111111111111101100:26, R/bits>>, L, A) -> dec_huffman(R, L - 26, <<A/binary, 242>>);
+dec_huffman(<<2#11111111111111111111101101:26, R/bits>>, L, A) -> dec_huffman(R, L - 26, <<A/binary, 243>>);
+dec_huffman(<<2#11111111111111111111101110:26, R/bits>>, L, A) -> dec_huffman(R, L - 26, <<A/binary, 255>>);
+dec_huffman(<<2#111111111111111111111011110:27, R/bits>>, L, A) -> dec_huffman(R, L - 27, <<A/binary, 203>>);
+dec_huffman(<<2#111111111111111111111011111:27, R/bits>>, L, A) -> dec_huffman(R, L - 27, <<A/binary, 204>>);
+dec_huffman(<<2#111111111111111111111100000:27, R/bits>>, L, A) -> dec_huffman(R, L - 27, <<A/binary, 211>>);
+dec_huffman(<<2#111111111111111111111100001:27, R/bits>>, L, A) -> dec_huffman(R, L - 27, <<A/binary, 212>>);
+dec_huffman(<<2#111111111111111111111100010:27, R/bits>>, L, A) -> dec_huffman(R, L - 27, <<A/binary, 214>>);
+dec_huffman(<<2#111111111111111111111100011:27, R/bits>>, L, A) -> dec_huffman(R, L - 27, <<A/binary, 221>>);
+dec_huffman(<<2#111111111111111111111100100:27, R/bits>>, L, A) -> dec_huffman(R, L - 27, <<A/binary, 222>>);
+dec_huffman(<<2#111111111111111111111100101:27, R/bits>>, L, A) -> dec_huffman(R, L - 27, <<A/binary, 223>>);
+dec_huffman(<<2#111111111111111111111100110:27, R/bits>>, L, A) -> dec_huffman(R, L - 27, <<A/binary, 241>>);
+dec_huffman(<<2#111111111111111111111100111:27, R/bits>>, L, A) -> dec_huffman(R, L - 27, <<A/binary, 244>>);
+dec_huffman(<<2#111111111111111111111101000:27, R/bits>>, L, A) -> dec_huffman(R, L - 27, <<A/binary, 245>>);
+dec_huffman(<<2#111111111111111111111101001:27, R/bits>>, L, A) -> dec_huffman(R, L - 27, <<A/binary, 246>>);
+dec_huffman(<<2#111111111111111111111101010:27, R/bits>>, L, A) -> dec_huffman(R, L - 27, <<A/binary, 247>>);
+dec_huffman(<<2#111111111111111111111101011:27, R/bits>>, L, A) -> dec_huffman(R, L - 27, <<A/binary, 248>>);
+dec_huffman(<<2#111111111111111111111101100:27, R/bits>>, L, A) -> dec_huffman(R, L - 27, <<A/binary, 250>>);
+dec_huffman(<<2#111111111111111111111101101:27, R/bits>>, L, A) -> dec_huffman(R, L - 27, <<A/binary, 251>>);
+dec_huffman(<<2#111111111111111111111101110:27, R/bits>>, L, A) -> dec_huffman(R, L - 27, <<A/binary, 252>>);
+dec_huffman(<<2#111111111111111111111101111:27, R/bits>>, L, A) -> dec_huffman(R, L - 27, <<A/binary, 253>>);
+dec_huffman(<<2#111111111111111111111110000:27, R/bits>>, L, A) -> dec_huffman(R, L - 27, <<A/binary, 254>>);
+dec_huffman(<<2#1111111111111111111111100010:28, R/bits>>, L, A) -> dec_huffman(R, L - 28, <<A/binary, 2>>);
+dec_huffman(<<2#1111111111111111111111100011:28, R/bits>>, L, A) -> dec_huffman(R, L - 28, <<A/binary, 3>>);
+dec_huffman(<<2#1111111111111111111111100100:28, R/bits>>, L, A) -> dec_huffman(R, L - 28, <<A/binary, 4>>);
+dec_huffman(<<2#1111111111111111111111100101:28, R/bits>>, L, A) -> dec_huffman(R, L - 28, <<A/binary, 5>>);
+dec_huffman(<<2#1111111111111111111111100110:28, R/bits>>, L, A) -> dec_huffman(R, L - 28, <<A/binary, 6>>);
+dec_huffman(<<2#1111111111111111111111100111:28, R/bits>>, L, A) -> dec_huffman(R, L - 28, <<A/binary, 7>>);
+dec_huffman(<<2#1111111111111111111111101000:28, R/bits>>, L, A) -> dec_huffman(R, L - 28, <<A/binary, 8>>);
+dec_huffman(<<2#1111111111111111111111101001:28, R/bits>>, L, A) -> dec_huffman(R, L - 28, <<A/binary, 11>>);
+dec_huffman(<<2#1111111111111111111111101010:28, R/bits>>, L, A) -> dec_huffman(R, L - 28, <<A/binary, 12>>);
+dec_huffman(<<2#1111111111111111111111101011:28, R/bits>>, L, A) -> dec_huffman(R, L - 28, <<A/binary, 14>>);
+dec_huffman(<<2#1111111111111111111111101100:28, R/bits>>, L, A) -> dec_huffman(R, L - 28, <<A/binary, 15>>);
+dec_huffman(<<2#1111111111111111111111101101:28, R/bits>>, L, A) -> dec_huffman(R, L - 28, <<A/binary, 16>>);
+dec_huffman(<<2#1111111111111111111111101110:28, R/bits>>, L, A) -> dec_huffman(R, L - 28, <<A/binary, 17>>);
+dec_huffman(<<2#1111111111111111111111101111:28, R/bits>>, L, A) -> dec_huffman(R, L - 28, <<A/binary, 18>>);
+dec_huffman(<<2#1111111111111111111111110000:28, R/bits>>, L, A) -> dec_huffman(R, L - 28, <<A/binary, 19>>);
+dec_huffman(<<2#1111111111111111111111110001:28, R/bits>>, L, A) -> dec_huffman(R, L - 28, <<A/binary, 20>>);
+dec_huffman(<<2#1111111111111111111111110010:28, R/bits>>, L, A) -> dec_huffman(R, L - 28, <<A/binary, 21>>);
+dec_huffman(<<2#1111111111111111111111110011:28, R/bits>>, L, A) -> dec_huffman(R, L - 28, <<A/binary, 23>>);
+dec_huffman(<<2#1111111111111111111111110100:28, R/bits>>, L, A) -> dec_huffman(R, L - 28, <<A/binary, 24>>);
+dec_huffman(<<2#1111111111111111111111110101:28, R/bits>>, L, A) -> dec_huffman(R, L - 28, <<A/binary, 25>>);
+dec_huffman(<<2#1111111111111111111111110110:28, R/bits>>, L, A) -> dec_huffman(R, L - 28, <<A/binary, 26>>);
+dec_huffman(<<2#1111111111111111111111110111:28, R/bits>>, L, A) -> dec_huffman(R, L - 28, <<A/binary, 27>>);
+dec_huffman(<<2#1111111111111111111111111000:28, R/bits>>, L, A) -> dec_huffman(R, L - 28, <<A/binary, 28>>);
+dec_huffman(<<2#1111111111111111111111111001:28, R/bits>>, L, A) -> dec_huffman(R, L - 28, <<A/binary, 29>>);
+dec_huffman(<<2#1111111111111111111111111010:28, R/bits>>, L, A) -> dec_huffman(R, L - 28, <<A/binary, 30>>);
+dec_huffman(<<2#1111111111111111111111111011:28, R/bits>>, L, A) -> dec_huffman(R, L - 28, <<A/binary, 31>>);
+dec_huffman(<<2#1111111111111111111111111100:28, R/bits>>, L, A) -> dec_huffman(R, L - 28, <<A/binary, 127>>);
+dec_huffman(<<2#1111111111111111111111111101:28, R/bits>>, L, A) -> dec_huffman(R, L - 28, <<A/binary, 220>>);
+dec_huffman(<<2#1111111111111111111111111110:28, R/bits>>, L, A) -> dec_huffman(R, L - 28, <<A/binary, 249>>);
+dec_huffman(<<2#111111111111111111111111111100:30, R/bits>>, L, A) -> dec_huffman(R, L - 30, <<A/binary, 10>>);
+dec_huffman(<<2#111111111111111111111111111101:30, R/bits>>, L, A) -> dec_huffman(R, L - 30, <<A/binary, 13>>);
+dec_huffman(<<2#111111111111111111111111111110:30, R/bits>>, L, A) -> dec_huffman(R, L - 30, <<A/binary, 22>>).
+
+-ifdef(TEST).
+req_decode_test() ->
+	%% First request (raw then huffman).
+	{Headers1, State1} = decode(<< 16#828684410f7777772e6578616d706c652e636f6d:160 >>),
+	{Headers1, State1} = decode(<< 16#828684418cf1e3c2e5f23a6ba0ab90f4ff:136 >>),
+	Headers1 = [
+		{<<":method">>, <<"GET">>},
+		{<<":scheme">>, <<"http">>},
+		{<<":path">>, <<"/">>},
+		{<<":authority">>, <<"www.example.com">>}
+	],
+	#state{size=57, dyn_table=[{57,{<<":authority">>, <<"www.example.com">>}}]} = State1,
+	%% Second request (raw then huffman).
+	{Headers2, State2} = decode(<< 16#828684be58086e6f2d6361636865:112 >>, State1),
+	{Headers2, State2} = decode(<< 16#828684be5886a8eb10649cbf:96 >>, State1),
+	Headers2 = [
+		{<<":method">>, <<"GET">>},
+		{<<":scheme">>, <<"http">>},
+		{<<":path">>, <<"/">>},
+		{<<":authority">>, <<"www.example.com">>},
+		{<<"cache-control">>, <<"no-cache">>}
+	],
+	#state{size=110, dyn_table=[
+		{53,{<<"cache-control">>, <<"no-cache">>}},
+		{57,{<<":authority">>, <<"www.example.com">>}}]} = State2,
+	%% Third request (raw then huffman).
+	{Headers3, State3} = decode(<< 16#828785bf400a637573746f6d2d6b65790c637573746f6d2d76616c7565:232 >>, State2),
+	{Headers3, State3} = decode(<< 16#828785bf408825a849e95ba97d7f8925a849e95bb8e8b4bf:192 >>, State2),
+	Headers3 = [
+		{<<":method">>, <<"GET">>},
+		{<<":scheme">>, <<"https">>},
+		{<<":path">>, <<"/index.html">>},
+		{<<":authority">>, <<"www.example.com">>},
+		{<<"custom-key">>, <<"custom-value">>}
+	],
+	#state{size=164, dyn_table=[
+		{54,{<<"custom-key">>, <<"custom-value">>}},
+		{53,{<<"cache-control">>, <<"no-cache">>}},
+		{57,{<<":authority">>, <<"www.example.com">>}}]} = State3,
+	ok.
+
+resp_decode_test() ->
+	%% Use a max_size of 256 to trigger header evictions.
+	State0 = init(256),
+	%% First response (raw then huffman).
+	{Headers1, State1} = decode(<< 16#4803333032580770726976617465611d4d6f6e2c203231204f637420323031332032303a31333a323120474d546e1768747470733a2f2f7777772e6578616d706c652e636f6d:560 >>, State0),
+	{Headers1, State1} = decode(<< 16#488264025885aec3771a4b6196d07abe941054d444a8200595040b8166e082a62d1bff6e919d29ad171863c78f0b97c8e9ae82ae43d3:432 >>, State0),
+	Headers1 = [
+		{<<":status">>, <<"302">>},
+		{<<"cache-control">>, <<"private">>},
+		{<<"date">>, <<"Mon, 21 Oct 2013 20:13:21 GMT">>},
+		{<<"location">>, <<"https://www.example.com">>}
+	],
+	#state{size=222, dyn_table=[
+		{63,{<<"location">>, <<"https://www.example.com">>}},
+		{65,{<<"date">>, <<"Mon, 21 Oct 2013 20:13:21 GMT">>}},
+		{52,{<<"cache-control">>, <<"private">>}},
+		{42,{<<":status">>, <<"302">>}}]} = State1,
+	%% Second response (raw then huffman).
+	{Headers2, State2} = decode(<< 16#4803333037c1c0bf:64 >>, State1),
+	{Headers2, State2} = decode(<< 16#4883640effc1c0bf:64 >>, State1),
+	Headers2 = [
+		{<<":status">>, <<"307">>},
+		{<<"cache-control">>, <<"private">>},
+		{<<"date">>, <<"Mon, 21 Oct 2013 20:13:21 GMT">>},
+		{<<"location">>, <<"https://www.example.com">>}
+	],
+	#state{size=180, dyn_table=[
+		{42,{<<":status">>, <<"307">>}},
+		{63,{<<"location">>, <<"https://www.example.com">>}},
+		{65,{<<"date">>, <<"Mon, 21 Oct 2013 20:13:21 GMT">>}},
+		{52,{<<"cache-control">>, <<"private">>}}]} = State2,
+	%% Third response (raw then huffman).
+	{Headers3, State3} = decode(<< 16#88c1611d4d6f6e2c203231204f637420323031332032303a31333a323220474d54c05a04677a69707738666f6f3d4153444a4b48514b425a584f5157454f50495541585157454f49553b206d61782d6167653d333630303b2076657273696f6e3d31:784 >>, State2),
+	{Headers3, State3} = decode(<< 16#88c16196d07abe941054d444a8200595040b8166e084a62d1bffc05a839bd9ab77ad94e7821dd7f2e6c7b335dfdfcd5b3960d5af27087f3672c1ab270fb5291f9587316065c003ed4ee5b1063d5007:632 >>, State2),
+	Headers3 = [
+		{<<":status">>, <<"200">>},
+		{<<"cache-control">>, <<"private">>},
+		{<<"date">>, <<"Mon, 21 Oct 2013 20:13:22 GMT">>},
+		{<<"location">>, <<"https://www.example.com">>},
+		{<<"content-encoding">>, <<"gzip">>},
+		{<<"set-cookie">>, <<"foo=ASDJKHQKBZXOQWEOPIUAXQWEOIU; max-age=3600; version=1">>}
+	],
+	#state{size=117, dyn_table=[
+		{98,{<<"set-cookie">>, <<"foo=ASDJKHQKBZXOQWEOPIUAXQWEOIU; max-age=3600; version=1">>}},
+		{52,{<<"content-encoding">>, <<"gzip">>}},
+		{65,{<<"date">>, <<"Mon, 21 Oct 2013 20:13:22 GMT">>}}]} = State3,
+	ok.
+-endif.
+
+%% Encoding.
+
+-spec encode(cow_http:headers()) -> iodata().
+encode(Headers) ->
+	encode(Headers, init(), #{}, []).
+
+-spec encode(cow_http:headers(), State) -> iodata() when State::state().
+encode(Headers, State) ->
+	encode(Headers, State, #{}, []).
+
+-spec encode(cow_http:headers(), State, opts()) -> iodata() when State::state().
+encode(Headers, State, Opts) ->
+	encode(Headers, State, Opts, []).
+
+%% @todo Handle cases where no/never indexing is expected.
+encode([], State, _, Acc) ->
+	{lists:reverse(Acc), State};
+encode([Header = {Name, Value}|Tail], State, Opts, Acc) ->
+	case table_find(Header, State) of
+		%% Indexed header field representation.
+		{field, Index} ->
+			encode(Tail, State, Opts, [enc_int7(Index, 2#1)|Acc]);
+		%% Literal header field representation: indexed name.
+		{name, Index} ->
+			State2 = table_insert(Header, State),
+			encode(Tail, State2, Opts, [[enc_int6(Index, 2#01), enc_str(Value, Opts)]|Acc]);
+		%% Literal header field representation: new name.
+		not_found ->
+			State2 = table_insert(Header, State),
+			encode(Tail, State2, Opts, [[<< 0:1, 1:1, 0:6 >>, enc_str(Name, Opts), enc_str(Value, Opts)]|Acc])
+	end.
+
+%% Encode an integer.
+
+enc_int6(Int, Prefix) when Int < 63 ->
+	<< Prefix:2, Int:6 >>;
+enc_int6(Int, Prefix) ->
+	[<< Prefix:2, 2#111111:6 >>|enc_big_int(Int - 63, [])].
+
+enc_int7(Int, Prefix) when Int < 127 ->
+	<< Prefix:1, Int:7 >>;
+enc_int7(Int, Prefix) ->
+	[<< Prefix:1, 2#1111111:7 >>|enc_big_int(Int - 127, [])].
+
+enc_big_int(Int, Acc) when Int < 128 ->
+	lists:reverse([<< Int:8 >>|Acc]);
+enc_big_int(Int, Acc) ->
+	enc_big_int(Int bsr 7, [<< 1:1, Int:7 >>|Acc]).
+
+%% Encode a string.
+
+enc_str(Str, Opts) ->
+	case maps:get(huffman, Opts, true) of
+		true ->
+			Str2 = enc_huffman(Str, <<>>),
+			[enc_int7(byte_size(Str2), 2#1), Str2];
+		false ->
+			[enc_int7(iolist_size(Str), 2#0), Str]
+	end.
+
+enc_huffman(<<>>, Acc) ->
+	case bit_size(Acc) rem 8 of
+		1 -> << Acc/bits, 2#1111111:7 >>;
+		2 -> << Acc/bits, 2#111111:6 >>;
+		3 -> << Acc/bits, 2#11111:5 >>;
+		4 -> << Acc/bits, 2#1111:4 >>;
+		5 -> << Acc/bits, 2#111:3 >>;
+		6 -> << Acc/bits, 2#11:2 >>;
+		7 -> << Acc/bits, 2#1:1 >>;
+		0 -> Acc
+	end;
+enc_huffman(<< 0, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111111000:13 >>);
+enc_huffman(<< 1, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#11111111111111111011000:23 >>);
+enc_huffman(<< 2, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111111111111111111100010:28 >>);
+enc_huffman(<< 3, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111111111111111111100011:28 >>);
+enc_huffman(<< 4, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111111111111111111100100:28 >>);
+enc_huffman(<< 5, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111111111111111111100101:28 >>);
+enc_huffman(<< 6, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111111111111111111100110:28 >>);
+enc_huffman(<< 7, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111111111111111111100111:28 >>);
+enc_huffman(<< 8, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111111111111111111101000:28 >>);
+enc_huffman(<< 9, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#111111111111111111101010:24 >>);
+enc_huffman(<< 10, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#111111111111111111111111111100:30 >>);
+enc_huffman(<< 11, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111111111111111111101001:28 >>);
+enc_huffman(<< 12, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111111111111111111101010:28 >>);
+enc_huffman(<< 13, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#111111111111111111111111111101:30 >>);
+enc_huffman(<< 14, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111111111111111111101011:28 >>);
+enc_huffman(<< 15, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111111111111111111101100:28 >>);
+enc_huffman(<< 16, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111111111111111111101101:28 >>);
+enc_huffman(<< 17, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111111111111111111101110:28 >>);
+enc_huffman(<< 18, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111111111111111111101111:28 >>);
+enc_huffman(<< 19, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111111111111111111110000:28 >>);
+enc_huffman(<< 20, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111111111111111111110001:28 >>);
+enc_huffman(<< 21, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111111111111111111110010:28 >>);
+enc_huffman(<< 22, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#111111111111111111111111111110:30 >>);
+enc_huffman(<< 23, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111111111111111111110011:28 >>);
+enc_huffman(<< 24, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111111111111111111110100:28 >>);
+enc_huffman(<< 25, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111111111111111111110101:28 >>);
+enc_huffman(<< 26, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111111111111111111110110:28 >>);
+enc_huffman(<< 27, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111111111111111111110111:28 >>);
+enc_huffman(<< 28, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111111111111111111111000:28 >>);
+enc_huffman(<< 29, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111111111111111111111001:28 >>);
+enc_huffman(<< 30, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111111111111111111111010:28 >>);
+enc_huffman(<< 31, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111111111111111111111011:28 >>);
+enc_huffman(<< 32, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#010100:6 >>);
+enc_huffman(<< 33, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111000:10 >>);
+enc_huffman(<< 34, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111001:10 >>);
+enc_huffman(<< 35, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#111111111010:12 >>);
+enc_huffman(<< 36, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111111001:13 >>);
+enc_huffman(<< 37, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#010101:6 >>);
+enc_huffman(<< 38, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#11111000:8 >>);
+enc_huffman(<< 39, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#11111111010:11 >>);
+enc_huffman(<< 40, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111010:10 >>);
+enc_huffman(<< 41, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111011:10 >>);
+enc_huffman(<< 42, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#11111001:8 >>);
+enc_huffman(<< 43, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#11111111011:11 >>);
+enc_huffman(<< 44, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#11111010:8 >>);
+enc_huffman(<< 45, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#010110:6 >>);
+enc_huffman(<< 46, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#010111:6 >>);
+enc_huffman(<< 47, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#011000:6 >>);
+enc_huffman(<< 48, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#00000:5 >>);
+enc_huffman(<< 49, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#00001:5 >>);
+enc_huffman(<< 50, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#00010:5 >>);
+enc_huffman(<< 51, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#011001:6 >>);
+enc_huffman(<< 52, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#011010:6 >>);
+enc_huffman(<< 53, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#011011:6 >>);
+enc_huffman(<< 54, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#011100:6 >>);
+enc_huffman(<< 55, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#011101:6 >>);
+enc_huffman(<< 56, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#011110:6 >>);
+enc_huffman(<< 57, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#011111:6 >>);
+enc_huffman(<< 58, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1011100:7 >>);
+enc_huffman(<< 59, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#11111011:8 >>);
+enc_huffman(<< 60, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#111111111111100:15 >>);
+enc_huffman(<< 61, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#100000:6 >>);
+enc_huffman(<< 62, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#111111111011:12 >>);
+enc_huffman(<< 63, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111100:10 >>);
+enc_huffman(<< 64, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111111010:13 >>);
+enc_huffman(<< 65, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#100001:6 >>);
+enc_huffman(<< 66, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1011101:7 >>);
+enc_huffman(<< 67, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1011110:7 >>);
+enc_huffman(<< 68, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1011111:7 >>);
+enc_huffman(<< 69, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1100000:7 >>);
+enc_huffman(<< 70, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1100001:7 >>);
+enc_huffman(<< 71, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1100010:7 >>);
+enc_huffman(<< 72, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1100011:7 >>);
+enc_huffman(<< 73, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1100100:7 >>);
+enc_huffman(<< 74, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1100101:7 >>);
+enc_huffman(<< 75, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1100110:7 >>);
+enc_huffman(<< 76, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1100111:7 >>);
+enc_huffman(<< 77, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1101000:7 >>);
+enc_huffman(<< 78, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1101001:7 >>);
+enc_huffman(<< 79, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1101010:7 >>);
+enc_huffman(<< 80, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1101011:7 >>);
+enc_huffman(<< 81, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1101100:7 >>);
+enc_huffman(<< 82, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1101101:7 >>);
+enc_huffman(<< 83, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1101110:7 >>);
+enc_huffman(<< 84, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1101111:7 >>);
+enc_huffman(<< 85, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1110000:7 >>);
+enc_huffman(<< 86, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1110001:7 >>);
+enc_huffman(<< 87, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1110010:7 >>);
+enc_huffman(<< 88, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#11111100:8 >>);
+enc_huffman(<< 89, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1110011:7 >>);
+enc_huffman(<< 90, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#11111101:8 >>);
+enc_huffman(<< 91, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111111011:13 >>);
+enc_huffman(<< 92, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111111111110000:19 >>);
+enc_huffman(<< 93, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111111100:13 >>);
+enc_huffman(<< 94, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#11111111111100:14 >>);
+enc_huffman(<< 95, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#100010:6 >>);
+enc_huffman(<< 96, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#111111111111101:15 >>);
+enc_huffman(<< 97, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#00011:5 >>);
+enc_huffman(<< 98, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#100011:6 >>);
+enc_huffman(<< 99, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#00100:5 >>);
+enc_huffman(<< 100, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#100100:6 >>);
+enc_huffman(<< 101, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#00101:5 >>);
+enc_huffman(<< 102, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#100101:6 >>);
+enc_huffman(<< 103, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#100110:6 >>);
+enc_huffman(<< 104, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#100111:6 >>);
+enc_huffman(<< 105, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#00110:5 >>);
+enc_huffman(<< 106, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1110100:7 >>);
+enc_huffman(<< 107, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1110101:7 >>);
+enc_huffman(<< 108, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#101000:6 >>);
+enc_huffman(<< 109, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#101001:6 >>);
+enc_huffman(<< 110, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#101010:6 >>);
+enc_huffman(<< 111, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#00111:5 >>);
+enc_huffman(<< 112, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#101011:6 >>);
+enc_huffman(<< 113, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1110110:7 >>);
+enc_huffman(<< 114, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#101100:6 >>);
+enc_huffman(<< 115, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#01000:5 >>);
+enc_huffman(<< 116, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#01001:5 >>);
+enc_huffman(<< 117, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#101101:6 >>);
+enc_huffman(<< 118, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1110111:7 >>);
+enc_huffman(<< 119, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111000:7 >>);
+enc_huffman(<< 120, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111001:7 >>);
+enc_huffman(<< 121, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111010:7 >>);
+enc_huffman(<< 122, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111011:7 >>);
+enc_huffman(<< 123, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#111111111111110:15 >>);
+enc_huffman(<< 124, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#11111111100:11 >>);
+enc_huffman(<< 125, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#11111111111101:14 >>);
+enc_huffman(<< 126, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111111101:13 >>);
+enc_huffman(<< 127, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111111111111111111111100:28 >>);
+enc_huffman(<< 128, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#11111111111111100110:20 >>);
+enc_huffman(<< 129, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111111111111010010:22 >>);
+enc_huffman(<< 130, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#11111111111111100111:20 >>);
+enc_huffman(<< 131, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#11111111111111101000:20 >>);
+enc_huffman(<< 132, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111111111111010011:22 >>);
+enc_huffman(<< 133, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111111111111010100:22 >>);
+enc_huffman(<< 134, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111111111111010101:22 >>);
+enc_huffman(<< 135, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#11111111111111111011001:23 >>);
+enc_huffman(<< 136, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111111111111010110:22 >>);
+enc_huffman(<< 137, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#11111111111111111011010:23 >>);
+enc_huffman(<< 138, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#11111111111111111011011:23 >>);
+enc_huffman(<< 139, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#11111111111111111011100:23 >>);
+enc_huffman(<< 140, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#11111111111111111011101:23 >>);
+enc_huffman(<< 141, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#11111111111111111011110:23 >>);
+enc_huffman(<< 142, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#111111111111111111101011:24 >>);
+enc_huffman(<< 143, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#11111111111111111011111:23 >>);
+enc_huffman(<< 144, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#111111111111111111101100:24 >>);
+enc_huffman(<< 145, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#111111111111111111101101:24 >>);
+enc_huffman(<< 146, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111111111111010111:22 >>);
+enc_huffman(<< 147, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#11111111111111111100000:23 >>);
+enc_huffman(<< 148, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#111111111111111111101110:24 >>);
+enc_huffman(<< 149, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#11111111111111111100001:23 >>);
+enc_huffman(<< 150, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#11111111111111111100010:23 >>);
+enc_huffman(<< 151, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#11111111111111111100011:23 >>);
+enc_huffman(<< 152, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#11111111111111111100100:23 >>);
+enc_huffman(<< 153, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#111111111111111011100:21 >>);
+enc_huffman(<< 154, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111111111111011000:22 >>);
+enc_huffman(<< 155, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#11111111111111111100101:23 >>);
+enc_huffman(<< 156, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111111111111011001:22 >>);
+enc_huffman(<< 157, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#11111111111111111100110:23 >>);
+enc_huffman(<< 158, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#11111111111111111100111:23 >>);
+enc_huffman(<< 159, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#111111111111111111101111:24 >>);
+enc_huffman(<< 160, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111111111111011010:22 >>);
+enc_huffman(<< 161, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#111111111111111011101:21 >>);
+enc_huffman(<< 162, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#11111111111111101001:20 >>);
+enc_huffman(<< 163, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111111111111011011:22 >>);
+enc_huffman(<< 164, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111111111111011100:22 >>);
+enc_huffman(<< 165, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#11111111111111111101000:23 >>);
+enc_huffman(<< 166, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#11111111111111111101001:23 >>);
+enc_huffman(<< 167, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#111111111111111011110:21 >>);
+enc_huffman(<< 168, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#11111111111111111101010:23 >>);
+enc_huffman(<< 169, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111111111111011101:22 >>);
+enc_huffman(<< 170, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111111111111011110:22 >>);
+enc_huffman(<< 171, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#111111111111111111110000:24 >>);
+enc_huffman(<< 172, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#111111111111111011111:21 >>);
+enc_huffman(<< 173, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111111111111011111:22 >>);
+enc_huffman(<< 174, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#11111111111111111101011:23 >>);
+enc_huffman(<< 175, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#11111111111111111101100:23 >>);
+enc_huffman(<< 176, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#111111111111111100000:21 >>);
+enc_huffman(<< 177, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#111111111111111100001:21 >>);
+enc_huffman(<< 178, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111111111111100000:22 >>);
+enc_huffman(<< 179, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#111111111111111100010:21 >>);
+enc_huffman(<< 180, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#11111111111111111101101:23 >>);
+enc_huffman(<< 181, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111111111111100001:22 >>);
+enc_huffman(<< 182, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#11111111111111111101110:23 >>);
+enc_huffman(<< 183, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#11111111111111111101111:23 >>);
+enc_huffman(<< 184, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#11111111111111101010:20 >>);
+enc_huffman(<< 185, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111111111111100010:22 >>);
+enc_huffman(<< 186, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111111111111100011:22 >>);
+enc_huffman(<< 187, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111111111111100100:22 >>);
+enc_huffman(<< 188, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#11111111111111111110000:23 >>);
+enc_huffman(<< 189, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111111111111100101:22 >>);
+enc_huffman(<< 190, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111111111111100110:22 >>);
+enc_huffman(<< 191, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#11111111111111111110001:23 >>);
+enc_huffman(<< 192, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#11111111111111111111100000:26 >>);
+enc_huffman(<< 193, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#11111111111111111111100001:26 >>);
+enc_huffman(<< 194, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#11111111111111101011:20 >>);
+enc_huffman(<< 195, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111111111110001:19 >>);
+enc_huffman(<< 196, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111111111111100111:22 >>);
+enc_huffman(<< 197, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#11111111111111111110010:23 >>);
+enc_huffman(<< 198, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111111111111101000:22 >>);
+enc_huffman(<< 199, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111111111111111101100:25 >>);
+enc_huffman(<< 200, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#11111111111111111111100010:26 >>);
+enc_huffman(<< 201, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#11111111111111111111100011:26 >>);
+enc_huffman(<< 202, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#11111111111111111111100100:26 >>);
+enc_huffman(<< 203, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#111111111111111111111011110:27 >>);
+enc_huffman(<< 204, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#111111111111111111111011111:27 >>);
+enc_huffman(<< 205, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#11111111111111111111100101:26 >>);
+enc_huffman(<< 206, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#111111111111111111110001:24 >>);
+enc_huffman(<< 207, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111111111111111101101:25 >>);
+enc_huffman(<< 208, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111111111110010:19 >>);
+enc_huffman(<< 209, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#111111111111111100011:21 >>);
+enc_huffman(<< 210, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#11111111111111111111100110:26 >>);
+enc_huffman(<< 211, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#111111111111111111111100000:27 >>);
+enc_huffman(<< 212, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#111111111111111111111100001:27 >>);
+enc_huffman(<< 213, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#11111111111111111111100111:26 >>);
+enc_huffman(<< 214, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#111111111111111111111100010:27 >>);
+enc_huffman(<< 215, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#111111111111111111110010:24 >>);
+enc_huffman(<< 216, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#111111111111111100100:21 >>);
+enc_huffman(<< 217, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#111111111111111100101:21 >>);
+enc_huffman(<< 218, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#11111111111111111111101000:26 >>);
+enc_huffman(<< 219, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#11111111111111111111101001:26 >>);
+enc_huffman(<< 220, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111111111111111111111101:28 >>);
+enc_huffman(<< 221, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#111111111111111111111100011:27 >>);
+enc_huffman(<< 222, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#111111111111111111111100100:27 >>);
+enc_huffman(<< 223, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#111111111111111111111100101:27 >>);
+enc_huffman(<< 224, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#11111111111111101100:20 >>);
+enc_huffman(<< 225, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#111111111111111111110011:24 >>);
+enc_huffman(<< 226, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#11111111111111101101:20 >>);
+enc_huffman(<< 227, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#111111111111111100110:21 >>);
+enc_huffman(<< 228, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111111111111101001:22 >>);
+enc_huffman(<< 229, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#111111111111111100111:21 >>);
+enc_huffman(<< 230, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#111111111111111101000:21 >>);
+enc_huffman(<< 231, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#11111111111111111110011:23 >>);
+enc_huffman(<< 232, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111111111111101010:22 >>);
+enc_huffman(<< 233, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111111111111101011:22 >>);
+enc_huffman(<< 234, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111111111111111101110:25 >>);
+enc_huffman(<< 235, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111111111111111101111:25 >>);
+enc_huffman(<< 236, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#111111111111111111110100:24 >>);
+enc_huffman(<< 237, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#111111111111111111110101:24 >>);
+enc_huffman(<< 238, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#11111111111111111111101010:26 >>);
+enc_huffman(<< 239, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#11111111111111111110100:23 >>);
+enc_huffman(<< 240, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#11111111111111111111101011:26 >>);
+enc_huffman(<< 241, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#111111111111111111111100110:27 >>);
+enc_huffman(<< 242, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#11111111111111111111101100:26 >>);
+enc_huffman(<< 243, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#11111111111111111111101101:26 >>);
+enc_huffman(<< 244, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#111111111111111111111100111:27 >>);
+enc_huffman(<< 245, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#111111111111111111111101000:27 >>);
+enc_huffman(<< 246, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#111111111111111111111101001:27 >>);
+enc_huffman(<< 247, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#111111111111111111111101010:27 >>);
+enc_huffman(<< 248, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#111111111111111111111101011:27 >>);
+enc_huffman(<< 249, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#1111111111111111111111111110:28 >>);
+enc_huffman(<< 250, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#111111111111111111111101100:27 >>);
+enc_huffman(<< 251, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#111111111111111111111101101:27 >>);
+enc_huffman(<< 252, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#111111111111111111111101110:27 >>);
+enc_huffman(<< 253, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#111111111111111111111101111:27 >>);
+enc_huffman(<< 254, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#111111111111111111111110000:27 >>);
+enc_huffman(<< 255, R/bits >>, A) -> enc_huffman(R, << A/bits, 2#11111111111111111111101110:26 >>).
+
+-ifdef(TEST).
+req_encode_test() ->
+	%% First request (raw then huffman).
+	Headers1 = [
+		{<<":method">>, <<"GET">>},
+		{<<":scheme">>, <<"http">>},
+		{<<":path">>, <<"/">>},
+		{<<":authority">>, <<"www.example.com">>}
+	],
+	{Raw1, State1} = encode(Headers1, init(), #{huffman => false}),
+	<< 16#828684410f7777772e6578616d706c652e636f6d:160 >> = iolist_to_binary(Raw1),
+	{Huff1, State1} = encode(Headers1),
+	<< 16#828684418cf1e3c2e5f23a6ba0ab90f4ff:136 >> = iolist_to_binary(Huff1),
+	#state{size=57, dyn_table=[{57,{<<":authority">>, <<"www.example.com">>}}]} = State1,
+	%% Second request (raw then huffman).
+	Headers2 = [
+		{<<":method">>, <<"GET">>},
+		{<<":scheme">>, <<"http">>},
+		{<<":path">>, <<"/">>},
+		{<<":authority">>, <<"www.example.com">>},
+		{<<"cache-control">>, <<"no-cache">>}
+	],
+	{Raw2, State2} = encode(Headers2, State1, #{huffman => false}),
+	<< 16#828684be58086e6f2d6361636865:112 >> = iolist_to_binary(Raw2),
+	{Huff2, State2} = encode(Headers2, State1),
+	<< 16#828684be5886a8eb10649cbf:96 >> = iolist_to_binary(Huff2),
+	#state{size=110, dyn_table=[
+		{53,{<<"cache-control">>, <<"no-cache">>}},
+		{57,{<<":authority">>, <<"www.example.com">>}}]} = State2,
+	%% Third request (raw then huffman).
+	Headers3 = [
+		{<<":method">>, <<"GET">>},
+		{<<":scheme">>, <<"https">>},
+		{<<":path">>, <<"/index.html">>},
+		{<<":authority">>, <<"www.example.com">>},
+		{<<"custom-key">>, <<"custom-value">>}
+	],
+	{Raw3, State3} = encode(Headers3, State2, #{huffman => false}),
+	<< 16#828785bf400a637573746f6d2d6b65790c637573746f6d2d76616c7565:232 >> = iolist_to_binary(Raw3),
+	{Huff3, State3} = encode(Headers3, State2),
+	<< 16#828785bf408825a849e95ba97d7f8925a849e95bb8e8b4bf:192 >> = iolist_to_binary(Huff3),
+	#state{size=164, dyn_table=[
+		{54,{<<"custom-key">>, <<"custom-value">>}},
+		{53,{<<"cache-control">>, <<"no-cache">>}},
+		{57,{<<":authority">>, <<"www.example.com">>}}]} = State3,
+	ok.
+
+resp_encode_test() ->
+	%% Use a max_size of 256 to trigger header evictions.
+	State0 = init(256),
+	%% First response (raw then huffman).
+	Headers1 = [
+		{<<":status">>, <<"302">>},
+		{<<"cache-control">>, <<"private">>},
+		{<<"date">>, <<"Mon, 21 Oct 2013 20:13:21 GMT">>},
+		{<<"location">>, <<"https://www.example.com">>}
+	],
+	{Raw1, State1} = encode(Headers1, State0, #{huffman => false}),
+	<< 16#4803333032580770726976617465611d4d6f6e2c203231204f637420323031332032303a31333a323120474d546e1768747470733a2f2f7777772e6578616d706c652e636f6d:560 >> = iolist_to_binary(Raw1),
+	{Huff1, State1} = encode(Headers1, State0),
+	<< 16#488264025885aec3771a4b6196d07abe941054d444a8200595040b8166e082a62d1bff6e919d29ad171863c78f0b97c8e9ae82ae43d3:432 >> = iolist_to_binary(Huff1),
+	#state{size=222, dyn_table=[
+		{63,{<<"location">>, <<"https://www.example.com">>}},
+		{65,{<<"date">>, <<"Mon, 21 Oct 2013 20:13:21 GMT">>}},
+		{52,{<<"cache-control">>, <<"private">>}},
+		{42,{<<":status">>, <<"302">>}}]} = State1,
+	%% Second response (raw then huffman).
+	Headers2 = [
+		{<<":status">>, <<"307">>},
+		{<<"cache-control">>, <<"private">>},
+		{<<"date">>, <<"Mon, 21 Oct 2013 20:13:21 GMT">>},
+		{<<"location">>, <<"https://www.example.com">>}
+	],
+	{Raw2, State2} = encode(Headers2, State1, #{huffman => false}),
+	<< 16#4803333037c1c0bf:64 >> = iolist_to_binary(Raw2),
+	{Huff2, State2} = encode(Headers2, State1),
+	<< 16#4883640effc1c0bf:64 >> = iolist_to_binary(Huff2),
+	#state{size=180, dyn_table=[
+		{42,{<<":status">>, <<"307">>}},
+		{63,{<<"location">>, <<"https://www.example.com">>}},
+		{65,{<<"date">>, <<"Mon, 21 Oct 2013 20:13:21 GMT">>}},
+		{52,{<<"cache-control">>, <<"private">>}}]} = State2,
+	%% Third response (raw then huffman).
+	Headers3 = [
+		{<<":status">>, <<"200">>},
+		{<<"cache-control">>, <<"private">>},
+		{<<"date">>, <<"Mon, 21 Oct 2013 20:13:22 GMT">>},
+		{<<"location">>, <<"https://www.example.com">>},
+		{<<"content-encoding">>, <<"gzip">>},
+		{<<"set-cookie">>, <<"foo=ASDJKHQKBZXOQWEOPIUAXQWEOIU; max-age=3600; version=1">>}
+	],
+	{Raw3, State3} = encode(Headers3, State2, #{huffman => false}),
+	<< 16#88c1611d4d6f6e2c203231204f637420323031332032303a31333a323220474d54c05a04677a69707738666f6f3d4153444a4b48514b425a584f5157454f50495541585157454f49553b206d61782d6167653d333630303b2076657273696f6e3d31:784 >> = iolist_to_binary(Raw3),
+	{Huff3, State3} = encode(Headers3, State2),
+	<< 16#88c16196d07abe941054d444a8200595040b8166e084a62d1bffc05a839bd9ab77ad94e7821dd7f2e6c7b335dfdfcd5b3960d5af27087f3672c1ab270fb5291f9587316065c003ed4ee5b1063d5007:632 >> = iolist_to_binary(Huff3),
+	#state{size=117, dyn_table=[
+		{98,{<<"set-cookie">>, <<"foo=ASDJKHQKBZXOQWEOPIUAXQWEOIU; max-age=3600; version=1">>}},
+		{52,{<<"content-encoding">>, <<"gzip">>}},
+		{65,{<<"date">>, <<"Mon, 21 Oct 2013 20:13:22 GMT">>}}]} = State3,
+	ok.
+-endif.
+
+%% Static and dynamic tables.
+
+%% @todo There must be a more efficient way.
+table_find({Name, Value}, State) ->
+	case table_find_field({Name, iolist_to_binary(Value)}, State) of
+		not_found ->
+			case table_find_name(Name, State) of
+				NotFound = not_found ->
+					NotFound;
+				Found ->
+					{name, Found}
+			end;
+		Found ->
+			{field, Found}
+	end.
+
+table_find_field({<<":authority">>, <<>>}, _) -> 1;
+table_find_field({<<":method">>, <<"GET">>}, _) -> 2;
+table_find_field({<<":method">>, <<"POST">>}, _) -> 3;
+table_find_field({<<":path">>, <<"/">>}, _) -> 4;
+table_find_field({<<":path">>, <<"/index.html">>}, _) -> 5;
+table_find_field({<<":scheme">>, <<"http">>}, _) -> 6;
+table_find_field({<<":scheme">>, <<"https">>}, _) -> 7;
+table_find_field({<<":status">>, <<"200">>}, _) -> 8;
+table_find_field({<<":status">>, <<"204">>}, _) -> 9;
+table_find_field({<<":status">>, <<"206">>}, _) -> 10;
+table_find_field({<<":status">>, <<"304">>}, _) -> 11;
+table_find_field({<<":status">>, <<"400">>}, _) -> 12;
+table_find_field({<<":status">>, <<"404">>}, _) -> 13;
+table_find_field({<<":status">>, <<"500">>}, _) -> 14;
+table_find_field({<<"accept-charset">>, <<>>}, _) -> 15;
+table_find_field({<<"accept-encoding">>, <<"gzip, deflate">>}, _) -> 16;
+table_find_field({<<"accept-language">>, <<>>}, _) -> 17;
+table_find_field({<<"accept-ranges">>, <<>>}, _) -> 18;
+table_find_field({<<"accept">>, <<>>}, _) -> 19;
+table_find_field({<<"access-control-allow-origin">>, <<>>}, _) -> 20;
+table_find_field({<<"age">>, <<>>}, _) -> 21;
+table_find_field({<<"allow">>, <<>>}, _) -> 22;
+table_find_field({<<"authorization">>, <<>>}, _) -> 23;
+table_find_field({<<"cache-control">>, <<>>}, _) -> 24;
+table_find_field({<<"content-disposition">>, <<>>}, _) -> 25;
+table_find_field({<<"content-encoding">>, <<>>}, _) -> 26;
+table_find_field({<<"content-language">>, <<>>}, _) -> 27;
+table_find_field({<<"content-length">>, <<>>}, _) -> 28;
+table_find_field({<<"content-location">>, <<>>}, _) -> 29;
+table_find_field({<<"content-range">>, <<>>}, _) -> 30;
+table_find_field({<<"content-type">>, <<>>}, _) -> 31;
+table_find_field({<<"cookie">>, <<>>}, _) -> 32;
+table_find_field({<<"date">>, <<>>}, _) -> 33;
+table_find_field({<<"etag">>, <<>>}, _) -> 34;
+table_find_field({<<"expect">>, <<>>}, _) -> 35;
+table_find_field({<<"expires">>, <<>>}, _) -> 36;
+table_find_field({<<"from">>, <<>>}, _) -> 37;
+table_find_field({<<"host">>, <<>>}, _) -> 38;
+table_find_field({<<"if-match">>, <<>>}, _) -> 39;
+table_find_field({<<"if-modified-since">>, <<>>}, _) -> 40;
+table_find_field({<<"if-none-match">>, <<>>}, _) -> 41;
+table_find_field({<<"if-range">>, <<>>}, _) -> 42;
+table_find_field({<<"if-unmodified-since">>, <<>>}, _) -> 43;
+table_find_field({<<"last-modified">>, <<>>}, _) -> 44;
+table_find_field({<<"link">>, <<>>}, _) -> 45;
+table_find_field({<<"location">>, <<>>}, _) -> 46;
+table_find_field({<<"max-forwards">>, <<>>}, _) -> 47;
+table_find_field({<<"proxy-authenticate">>, <<>>}, _) -> 48;
+table_find_field({<<"proxy-authorization">>, <<>>}, _) -> 49;
+table_find_field({<<"range">>, <<>>}, _) -> 50;
+table_find_field({<<"referer">>, <<>>}, _) -> 51;
+table_find_field({<<"refresh">>, <<>>}, _) -> 52;
+table_find_field({<<"retry-after">>, <<>>}, _) -> 53;
+table_find_field({<<"server">>, <<>>}, _) -> 54;
+table_find_field({<<"set-cookie">>, <<>>}, _) -> 55;
+table_find_field({<<"strict-transport-security">>, <<>>}, _) -> 56;
+table_find_field({<<"transfer-encoding">>, <<>>}, _) -> 57;
+table_find_field({<<"user-agent">>, <<>>}, _) -> 58;
+table_find_field({<<"vary">>, <<>>}, _) -> 59;
+table_find_field({<<"via">>, <<>>}, _) -> 60;
+table_find_field({<<"www-authenticate">>, <<>>}, _) -> 61;
+table_find_field(Header, #state{dyn_table=DynamicTable}) ->
+	table_find_field_dyn(Header, DynamicTable, 62).
+
+table_find_field_dyn(_, [], _) -> not_found;
+table_find_field_dyn(Header, [{_, Header}|_], Index) -> Index;
+table_find_field_dyn(Header, [_|Tail], Index) -> table_find_field_dyn(Header, Tail, Index + 1).
+
+table_find_name(<<":authority">>, _) -> 1;
+table_find_name(<<":method">>, _) -> 2;
+table_find_name(<<":path">>, _) -> 4;
+table_find_name(<<":scheme">>, _) -> 6;
+table_find_name(<<":status">>, _) -> 8;
+table_find_name(<<"accept-charset">>, _) -> 15;
+table_find_name(<<"accept-encoding">>, _) -> 16;
+table_find_name(<<"accept-language">>, _) -> 17;
+table_find_name(<<"accept-ranges">>, _) -> 18;
+table_find_name(<<"accept">>, _) -> 19;
+table_find_name(<<"access-control-allow-origin">>, _) -> 20;
+table_find_name(<<"age">>, _) -> 21;
+table_find_name(<<"allow">>, _) -> 22;
+table_find_name(<<"authorization">>, _) -> 23;
+table_find_name(<<"cache-control">>, _) -> 24;
+table_find_name(<<"content-disposition">>, _) -> 25;
+table_find_name(<<"content-encoding">>, _) -> 26;
+table_find_name(<<"content-language">>, _) -> 27;
+table_find_name(<<"content-length">>, _) -> 28;
+table_find_name(<<"content-location">>, _) -> 29;
+table_find_name(<<"content-range">>, _) -> 30;
+table_find_name(<<"content-type">>, _) -> 31;
+table_find_name(<<"cookie">>, _) -> 32;
+table_find_name(<<"date">>, _) -> 33;
+table_find_name(<<"etag">>, _) -> 34;
+table_find_name(<<"expect">>, _) -> 35;
+table_find_name(<<"expires">>, _) -> 36;
+table_find_name(<<"from">>, _) -> 37;
+table_find_name(<<"host">>, _) -> 38;
+table_find_name(<<"if-match">>, _) -> 39;
+table_find_name(<<"if-modified-since">>, _) -> 40;
+table_find_name(<<"if-none-match">>, _) -> 41;
+table_find_name(<<"if-range">>, _) -> 42;
+table_find_name(<<"if-unmodified-since">>, _) -> 43;
+table_find_name(<<"last-modified">>, _) -> 44;
+table_find_name(<<"link">>, _) -> 45;
+table_find_name(<<"location">>, _) -> 46;
+table_find_name(<<"max-forwards">>, _) -> 47;
+table_find_name(<<"proxy-authenticate">>, _) -> 48;
+table_find_name(<<"proxy-authorization">>, _) -> 49;
+table_find_name(<<"range">>, _) -> 50;
+table_find_name(<<"referer">>, _) -> 51;
+table_find_name(<<"refresh">>, _) -> 52;
+table_find_name(<<"retry-after">>, _) -> 53;
+table_find_name(<<"server">>, _) -> 54;
+table_find_name(<<"set-cookie">>, _) -> 55;
+table_find_name(<<"strict-transport-security">>, _) -> 56;
+table_find_name(<<"transfer-encoding">>, _) -> 57;
+table_find_name(<<"user-agent">>, _) -> 58;
+table_find_name(<<"vary">>, _) -> 59;
+table_find_name(<<"via">>, _) -> 60;
+table_find_name(<<"www-authenticate">>, _) -> 61;
+table_find_name(Name, #state{dyn_table=DynamicTable}) ->
+	table_find_name_dyn(Name, DynamicTable, 62).
+
+table_find_name_dyn(_, [], _) -> not_found;
+table_find_name_dyn(Name, [{Name, _}|_], Index) -> Index;
+table_find_name_dyn(Name, [_|Tail], Index) -> table_find_name_dyn(Name, Tail, Index + 1).
+
+table_get(1, _) -> {<<":authority">>, <<>>};
+table_get(2, _) -> {<<":method">>, <<"GET">>};
+table_get(3, _) -> {<<":method">>, <<"POST">>};
+table_get(4, _) -> {<<":path">>, <<"/">>};
+table_get(5, _) -> {<<":path">>, <<"/index.html">>};
+table_get(6, _) -> {<<":scheme">>, <<"http">>};
+table_get(7, _) -> {<<":scheme">>, <<"https">>};
+table_get(8, _) -> {<<":status">>, <<"200">>};
+table_get(9, _) -> {<<":status">>, <<"204">>};
+table_get(10, _) -> {<<":status">>, <<"206">>};
+table_get(11, _) -> {<<":status">>, <<"304">>};
+table_get(12, _) -> {<<":status">>, <<"400">>};
+table_get(13, _) -> {<<":status">>, <<"404">>};
+table_get(14, _) -> {<<":status">>, <<"500">>};
+table_get(15, _) -> {<<"accept-charset">>, <<>>};
+table_get(16, _) -> {<<"accept-encoding">>, <<"gzip, deflate">>};
+table_get(17, _) -> {<<"accept-language">>, <<>>};
+table_get(18, _) -> {<<"accept-ranges">>, <<>>};
+table_get(19, _) -> {<<"accept">>, <<>>};
+table_get(20, _) -> {<<"access-control-allow-origin">>, <<>>};
+table_get(21, _) -> {<<"age">>, <<>>};
+table_get(22, _) -> {<<"allow">>, <<>>};
+table_get(23, _) -> {<<"authorization">>, <<>>};
+table_get(24, _) -> {<<"cache-control">>, <<>>};
+table_get(25, _) -> {<<"content-disposition">>, <<>>};
+table_get(26, _) -> {<<"content-encoding">>, <<>>};
+table_get(27, _) -> {<<"content-language">>, <<>>};
+table_get(28, _) -> {<<"content-length">>, <<>>};
+table_get(29, _) -> {<<"content-location">>, <<>>};
+table_get(30, _) -> {<<"content-range">>, <<>>};
+table_get(31, _) -> {<<"content-type">>, <<>>};
+table_get(32, _) -> {<<"cookie">>, <<>>};
+table_get(33, _) -> {<<"date">>, <<>>};
+table_get(34, _) -> {<<"etag">>, <<>>};
+table_get(35, _) -> {<<"expect">>, <<>>};
+table_get(36, _) -> {<<"expires">>, <<>>};
+table_get(37, _) -> {<<"from">>, <<>>};
+table_get(38, _) -> {<<"host">>, <<>>};
+table_get(39, _) -> {<<"if-match">>, <<>>};
+table_get(40, _) -> {<<"if-modified-since">>, <<>>};
+table_get(41, _) -> {<<"if-none-match">>, <<>>};
+table_get(42, _) -> {<<"if-range">>, <<>>};
+table_get(43, _) -> {<<"if-unmodified-since">>, <<>>};
+table_get(44, _) -> {<<"last-modified">>, <<>>};
+table_get(45, _) -> {<<"link">>, <<>>};
+table_get(46, _) -> {<<"location">>, <<>>};
+table_get(47, _) -> {<<"max-forwards">>, <<>>};
+table_get(48, _) -> {<<"proxy-authenticate">>, <<>>};
+table_get(49, _) -> {<<"proxy-authorization">>, <<>>};
+table_get(50, _) -> {<<"range">>, <<>>};
+table_get(51, _) -> {<<"referer">>, <<>>};
+table_get(52, _) -> {<<"refresh">>, <<>>};
+table_get(53, _) -> {<<"retry-after">>, <<>>};
+table_get(54, _) -> {<<"server">>, <<>>};
+table_get(55, _) -> {<<"set-cookie">>, <<>>};
+table_get(56, _) -> {<<"strict-transport-security">>, <<>>};
+table_get(57, _) -> {<<"transfer-encoding">>, <<>>};
+table_get(58, _) -> {<<"user-agent">>, <<>>};
+table_get(59, _) -> {<<"vary">>, <<>>};
+table_get(60, _) -> {<<"via">>, <<>>};
+table_get(61, _) -> {<<"www-authenticate">>, <<>>};
+table_get(Index, #state{dyn_table=DynamicTable}) ->
+	{_, Header} = lists:nth(Index - 61, DynamicTable),
+	Header.
+
+table_get_name(1, _) -> <<":authority">>;
+table_get_name(2, _) -> <<":method">>;
+table_get_name(3, _) -> <<":method">>;
+table_get_name(4, _) -> <<":path">>;
+table_get_name(5, _) -> <<":path">>;
+table_get_name(6, _) -> <<":scheme">>;
+table_get_name(7, _) -> <<":scheme">>;
+table_get_name(8, _) -> <<":status">>;
+table_get_name(9, _) -> <<":status">>;
+table_get_name(10, _) -> <<":status">>;
+table_get_name(11, _) -> <<":status">>;
+table_get_name(12, _) -> <<":status">>;
+table_get_name(13, _) -> <<":status">>;
+table_get_name(14, _) -> <<":status">>;
+table_get_name(15, _) -> <<"accept-charset">>;
+table_get_name(16, _) -> <<"accept-encoding">>;
+table_get_name(17, _) -> <<"accept-language">>;
+table_get_name(18, _) -> <<"accept-ranges">>;
+table_get_name(19, _) -> <<"accept">>;
+table_get_name(20, _) -> <<"access-control-allow-origin">>;
+table_get_name(21, _) -> <<"age">>;
+table_get_name(22, _) -> <<"allow">>;
+table_get_name(23, _) -> <<"authorization">>;
+table_get_name(24, _) -> <<"cache-control">>;
+table_get_name(25, _) -> <<"content-disposition">>;
+table_get_name(26, _) -> <<"content-encoding">>;
+table_get_name(27, _) -> <<"content-language">>;
+table_get_name(28, _) -> <<"content-length">>;
+table_get_name(29, _) -> <<"content-location">>;
+table_get_name(30, _) -> <<"content-range">>;
+table_get_name(31, _) -> <<"content-type">>;
+table_get_name(32, _) -> <<"cookie">>;
+table_get_name(33, _) -> <<"date">>;
+table_get_name(34, _) -> <<"etag">>;
+table_get_name(35, _) -> <<"expect">>;
+table_get_name(36, _) -> <<"expires">>;
+table_get_name(37, _) -> <<"from">>;
+table_get_name(38, _) -> <<"host">>;
+table_get_name(39, _) -> <<"if-match">>;
+table_get_name(40, _) -> <<"if-modified-since">>;
+table_get_name(41, _) -> <<"if-none-match">>;
+table_get_name(42, _) -> <<"if-range">>;
+table_get_name(43, _) -> <<"if-unmodified-since">>;
+table_get_name(44, _) -> <<"last-modified">>;
+table_get_name(45, _) -> <<"link">>;
+table_get_name(46, _) -> <<"location">>;
+table_get_name(47, _) -> <<"max-forwards">>;
+table_get_name(48, _) -> <<"proxy-authenticate">>;
+table_get_name(49, _) -> <<"proxy-authorization">>;
+table_get_name(50, _) -> <<"range">>;
+table_get_name(51, _) -> <<"referer">>;
+table_get_name(52, _) -> <<"refresh">>;
+table_get_name(53, _) -> <<"retry-after">>;
+table_get_name(54, _) -> <<"server">>;
+table_get_name(55, _) -> <<"set-cookie">>;
+table_get_name(56, _) -> <<"strict-transport-security">>;
+table_get_name(57, _) -> <<"transfer-encoding">>;
+table_get_name(58, _) -> <<"user-agent">>;
+table_get_name(59, _) -> <<"vary">>;
+table_get_name(60, _) -> <<"via">>;
+table_get_name(61, _) -> <<"www-authenticate">>;
+table_get_name(Index, #state{dyn_table=DynamicTable}) ->
+	{_, {Name, _}} = lists:nth(Index - 61, DynamicTable),
+	Name.
+
+table_insert(Entry = {Name, Value}, State=#state{size=Size, max_size=MaxSize, dyn_table=DynamicTable}) ->
+	EntrySize = byte_size(Name) + byte_size(Value) + 32,
+	Size2 = Size + EntrySize,
+	{DynamicTable2, Size3} = if
+		Size + EntrySize > MaxSize ->
+			table_resize(DynamicTable, MaxSize - EntrySize, 0, []);
+		true ->
+			{DynamicTable, Size2}
+	end,
+	State#state{size=Size3, dyn_table=[{EntrySize, Entry}|DynamicTable2]}.
+
+table_resize([], _, Size, Acc) ->
+	{lists:reverse(Acc), Size};
+table_resize([{EntrySize, _}|_], MaxSize, Size, Acc) when Size + EntrySize > MaxSize ->
+	{lists:reverse(Acc), Size};
+table_resize([Entry = {EntrySize, _}|Tail], MaxSize, Size, Acc) ->
+	table_resize(Tail, MaxSize, Size + EntrySize, [Entry|Acc]).
+
+table_update_size(0, State) ->
+	State#state{size=0, max_size=0, dyn_table=[]};
+table_update_size(MaxSize, State=#state{max_size=MaxSize}) ->
+	State;
+table_update_size(MaxSize, #state{dyn_table=DynTable}) ->
+	{DynTable2, Size} = table_resize(DynTable, MaxSize, 0, []),
+	#state{size=Size, max_size=MaxSize, dyn_table=DynTable2}.
+
+-ifdef(TEST).
+prop_str_raw() ->
+	?FORALL(Str, binary(), begin
+		{Str, <<>>} =:= dec_str(iolist_to_binary(enc_str(Str, #{huffman => false})))
+	end).
+
+prop_str_huffman() ->
+	?FORALL(Str, binary(), begin
+		{Str, <<>>} =:= dec_str(iolist_to_binary(enc_str(Str, #{huffman => true})))
+	end).
+-endif.