Implement a minimal decoder for HPACK (HTTP/2 compression)

The decoder assumes everything is encoded as literals without indexing and does
not use Huffman encoding.

The decoder will be expanded to handle everything in the spec in future CLs.

This lands server change 60496510 by akalin.

BUG=339578

Review URL: https://codereview.chromium.org/150453002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@248064 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 98 insertions, 0 deletions

diff --git a/net/spdy/hpack_decoder_test.cc b/net/spdy/hpack_decoder_test.cc
new file mode 100644
index 0000000..dcc5ad8
--- /dev/null
+++ b/net/spdy/hpack_decoder_test.cc
@@ -0,0 +1,98 @@
+// Copyright 2014 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.
+
+#include "net/spdy/hpack_decoder.h"
+
+#include <map>
+#include <string>
+
+#include "base/basictypes.h"
+#include "net/spdy/hpack_encoder.h"
+#include "net/spdy/hpack_input_stream.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace net {
+
+namespace {
+
+using base::StringPiece;
+using std::string;
+
+// Decoding an encoded name with a valid string literal should work.
+TEST(HpackDecoderTest, DecodeNextNameLiteral) {
+  HpackDecoder decoder(kuint32max);
+  HpackInputStream input_stream(kuint32max, StringPiece("\x00\x04name", 6));
+
+  StringPiece string_piece;
+  EXPECT_TRUE(decoder.DecodeNextNameForTest(&input_stream, &string_piece));
+  EXPECT_EQ("name", string_piece);
+  EXPECT_FALSE(input_stream.HasMoreData());
+}
+
+// Decoding an encoded name with a valid index should work.
+TEST(HpackDecoderTest, DecodeNextNameIndexed) {
+  HpackDecoder decoder(kuint32max);
+  HpackInputStream input_stream(kuint32max, "\x01");
+
+  StringPiece string_piece;
+  EXPECT_TRUE(decoder.DecodeNextNameForTest(&input_stream, &string_piece));
+  EXPECT_EQ(":authority", string_piece);
+  EXPECT_FALSE(input_stream.HasMoreData());
+}
+
+// Decoding an encoded name with an invalid index should fail.
+TEST(HpackDecoderTest, DecodeNextNameInvalidIndex) {
+  // One more than the number of static table entries.
+  HpackDecoder decoder(kuint32max);
+  HpackInputStream input_stream(kuint32max, "\x3d");
+
+  StringPiece string_piece;
+  EXPECT_FALSE(decoder.DecodeNextNameForTest(&input_stream, &string_piece));
+}
+
+// Decoding two valid encoded literal headers with no indexing should
+// work.
+TEST(HpackDecoderTest, LiteralHeaderNoIndexing) {
+  HpackDecoder decoder(kuint32max);
+  HpackHeaderPairVector header_list;
+  // First header with indexed name, second header with string literal
+  // name.
+  EXPECT_TRUE(decoder.DecodeHeaderSet(
+      "\x44\x0c/sample/path\x40\x06:path2\x0e/sample/path/2",
+      &header_list));
+  std::map<string, string> header_set(header_list.begin(), header_list.end());
+
+  std::map<string, string> expected_header_set;
+  expected_header_set[":path"] = "/sample/path";
+  expected_header_set[":path2"] = "/sample/path/2";
+  EXPECT_EQ(expected_header_set, header_set);
+}
+
+// Round-tripping the header set from E.2.1 should work.
+TEST(HpackDecoderTest, BasicE21) {
+  HpackEncoder encoder(kuint32max);
+
+  std::map<string, string> expected_header_set;
+  expected_header_set[":method"] = "GET";
+  expected_header_set[":scheme"] = "http";
+  expected_header_set[":path"] = "/";
+  expected_header_set[":authority"] = "www.example.com";
+
+  string encoded_header_set;
+  EXPECT_TRUE(encoder.EncodeHeaderSet(
+      expected_header_set, &encoded_header_set));
+
+  HpackDecoder decoder(kuint32max);
+  HpackHeaderPairVector header_list;
+  EXPECT_TRUE(decoder.DecodeHeaderSet(encoded_header_set, &header_list));
+  std::map<string, string> header_set(header_list.begin(), header_list.end());
+  EXPECT_EQ(expected_header_set, header_set);
+}
+
+// TODO(akalin): Add test to exercise emission of the reference set
+// once we can decode opcodes that add to the reference set.
+
+}  // namespace
+
+}  // namespace net