| // Copyright 2008 The open-vcdiff Authors. All Rights Reserved. |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| |
| #include <config.h> |
| #include "google/vcencoder.h" |
| #include <stdlib.h> // free, posix_memalign |
| #include <string.h> // memcpy |
| #include <algorithm> |
| #include <string> |
| #include <vector> |
| #include "blockhash.h" |
| #include "checksum.h" |
| #include "testing.h" |
| #include "varint_bigendian.h" |
| #include "google/vcdecoder.h" |
| #include "google/jsonwriter.h" |
| #include "vcdiff_defs.h" |
| |
| #ifdef HAVE_EXT_ROPE |
| #include <ext/rope> |
| #include "output_string_crope.h" |
| using __gnu_cxx::crope; |
| #endif // HAVE_EXT_ROPE |
| |
| #ifdef HAVE_MALLOC_H |
| #include <malloc.h> |
| #endif // HAVE_MALLOC_H |
| |
| #ifdef HAVE_SYS_MMAN_H |
| #if !defined(_XOPEN_SOURCE) || _XOPEN_SOURCE < 600 |
| #undef _XOPEN_SOURCE |
| #define _XOPEN_SOURCE 600 // posix_memalign |
| #endif |
| #include <sys/mman.h> // mprotect |
| #endif // HAVE_SYS_MMAN_H |
| |
| #ifdef HAVE_UNISTD_H |
| #include <unistd.h> // getpagesize |
| #endif // HAVE_UNISTD_H |
| |
| namespace open_vcdiff { |
| namespace { |
| |
| static const size_t kFileHeaderSize = sizeof(DeltaFileHeader); |
| |
| // This is to check the maximum possible encoding size |
| // if using a single ADD instruction, so assume that the |
| // dictionary size, the length of the ADD data, the size |
| // of the target window, and the length of the delta window |
| // are all two-byte Varints, that is, 128 <= length < 4096. |
| // This figure includes three extra bytes for a zero-sized |
| // ADD instruction with a two-byte Varint explicit size. |
| // Any additional COPY & ADD instructions must reduce |
| // the length of the encoding from this maximum. |
| static const size_t kWindowHeaderSize = 21; |
| |
| class VerifyEncodedBytesTest : public testing::Test { |
| public: |
| typedef std::string string; |
| |
| VerifyEncodedBytesTest() : delta_index_(0) { } |
| virtual ~VerifyEncodedBytesTest() { } |
| |
| void ExpectByte(unsigned char b) { |
| EXPECT_EQ(b, static_cast<unsigned char>(delta_[delta_index_])); |
| ++delta_index_; |
| } |
| |
| void ExpectString(const char* s) { |
| const size_t size = strlen(s); // don't include terminating NULL char |
| EXPECT_EQ(s, string(delta_data() + delta_index_, size)); |
| delta_index_ += size; |
| } |
| |
| void ExpectNoMoreBytes() { |
| EXPECT_EQ(delta_index_, delta_size()); |
| } |
| |
| void ExpectSize(size_t size) { |
| const char* delta_size_pos = &delta_[delta_index_]; |
| EXPECT_EQ(size, |
| static_cast<size_t>( |
| VarintBE<int32_t>::Parse(delta_data() + delta_size(), |
| &delta_size_pos))); |
| delta_index_ = delta_size_pos - delta_data(); |
| } |
| |
| void ExpectChecksum(VCDChecksum checksum) { |
| const char* delta_checksum_pos = &delta_[delta_index_]; |
| EXPECT_EQ(checksum, |
| static_cast<VCDChecksum>( |
| VarintBE<int64_t>::Parse(delta_data() + delta_size(), |
| &delta_checksum_pos))); |
| delta_index_ = delta_checksum_pos - delta_data(); |
| } |
| |
| const string& delta_as_const() const { return delta_; } |
| string* delta() { return &delta_; } |
| |
| const char* delta_data() const { return delta_as_const().data(); } |
| size_t delta_size() const { return delta_as_const().size(); } |
| |
| private: |
| string delta_; |
| size_t delta_index_; |
| }; |
| |
| class VCDiffEncoderTest : public VerifyEncodedBytesTest { |
| protected: |
| static const char kDictionary[]; |
| static const char kTarget[]; |
| static const char kJSONDiff[]; |
| static const char kNonAscii[]; |
| |
| VCDiffEncoderTest(); |
| virtual ~VCDiffEncoderTest() { } |
| |
| void TestWithFixedChunkSize(VCDiffStreamingEncoder *encoder, |
| VCDiffStreamingDecoder *decoder, |
| size_t chunk_size); |
| void TestWithEncodedChunkVector(size_t chunk_size); |
| |
| HashedDictionary hashed_dictionary_; |
| VCDiffStreamingEncoder encoder_; |
| VCDiffStreamingDecoder decoder_; |
| VCDiffEncoder simple_encoder_; |
| VCDiffDecoder simple_decoder_; |
| VCDiffStreamingEncoder json_encoder_; |
| VCDiffStreamingEncoder external_encoder_; |
| VCDiffEncoder nonascii_simple_encoder_; |
| |
| string result_target_; |
| }; |
| |
| const char VCDiffEncoderTest::kDictionary[] = |
| "\"Just the place for a Snark!\" the Bellman cried,\n" |
| "As he landed his crew with care;\n" |
| "Supporting each man on the top of the tide\n" |
| "By a finger entwined in his hair.\n"; |
| |
| const char VCDiffEncoderTest::kTarget[] = |
| "\"Just the place for a Snark! I have said it twice:\n" |
| "That alone should encourage the crew.\n" |
| "Just the place for a Snark! I have said it thrice:\n" |
| "What I tell you three times is true.\"\n"; |
| |
| const char VCDiffEncoderTest::kJSONDiff[] = |
| "[\"\\\"Just the place for a Snark! I have said it twice:\\n" |
| "That alone should encourage the crew.\\n\"," |
| "161,44," |
| "\"hrice:\\nWhat I tell you three times is true.\\\"\\n\"]"; |
| |
| // NonASCII string "foo\x128". |
| const char VCDiffEncoderTest::kNonAscii[] = {102, 111, 111, 128, 0}; |
| |
| VCDiffEncoderTest::VCDiffEncoderTest() |
| : hashed_dictionary_(kDictionary, sizeof(kDictionary)), |
| encoder_(&hashed_dictionary_, |
| VCD_FORMAT_INTERLEAVED | VCD_FORMAT_CHECKSUM, |
| /* look_for_target_matches = */ true), |
| simple_encoder_(kDictionary, sizeof(kDictionary)), |
| json_encoder_(&hashed_dictionary_, |
| VCD_FORMAT_JSON, |
| /* look_for_target_matches = */ true), |
| external_encoder_(&hashed_dictionary_, |
| 0, |
| /* look_for_target_matches = */ true, |
| new JSONCodeTableWriter()), |
| nonascii_simple_encoder_(kNonAscii, sizeof(kNonAscii)) { |
| EXPECT_TRUE(hashed_dictionary_.Init()); |
| } |
| |
| TEST_F(VCDiffEncoderTest, EncodeBeforeStartEncoding) { |
| EXPECT_FALSE(encoder_.EncodeChunk(kTarget, strlen(kTarget), delta())); |
| } |
| |
| TEST_F(VCDiffEncoderTest, FinishBeforeStartEncoding) { |
| EXPECT_FALSE(encoder_.FinishEncoding(delta())); |
| } |
| |
| TEST_F(VCDiffEncoderTest, EncodeDecodeNothing) { |
| HashedDictionary nothing_dictionary("", 0); |
| EXPECT_TRUE(nothing_dictionary.Init()); |
| VCDiffStreamingEncoder nothing_encoder(¬hing_dictionary, |
| VCD_STANDARD_FORMAT, |
| false); |
| EXPECT_TRUE(nothing_encoder.StartEncoding(delta())); |
| EXPECT_TRUE(nothing_encoder.FinishEncoding(delta())); |
| decoder_.StartDecoding("", 0); |
| EXPECT_TRUE(decoder_.DecodeChunk(delta_data(), |
| delta_size(), |
| &result_target_)); |
| EXPECT_TRUE(decoder_.FinishDecoding()); |
| EXPECT_TRUE(result_target_.empty()); |
| } |
| |
| TEST_F(VCDiffEncoderTest, EncodeNothingJSON) { |
| HashedDictionary nothing_dictionary("", 0); |
| EXPECT_TRUE(nothing_dictionary.Init()); |
| VCDiffStreamingEncoder nothing_encoder(¬hing_dictionary, |
| VCD_FORMAT_JSON, |
| false); |
| EXPECT_TRUE(nothing_encoder.StartEncoding(delta())); |
| EXPECT_TRUE(nothing_encoder.FinishEncoding(delta())); |
| EXPECT_EQ("", delta_as_const()); |
| } |
| |
| // A NULL dictionary pointer is legal as long as the dictionary size is 0. |
| TEST_F(VCDiffEncoderTest, EncodeDecodeNullDictionaryPtr) { |
| HashedDictionary null_dictionary(NULL, 0); |
| EXPECT_TRUE(null_dictionary.Init()); |
| VCDiffStreamingEncoder null_encoder(&null_dictionary, |
| VCD_STANDARD_FORMAT, |
| false); |
| EXPECT_TRUE(null_encoder.StartEncoding(delta())); |
| EXPECT_TRUE(null_encoder.EncodeChunk(kTarget, strlen(kTarget), delta())); |
| EXPECT_TRUE(null_encoder.FinishEncoding(delta())); |
| EXPECT_GE(strlen(kTarget) + kFileHeaderSize + kWindowHeaderSize, |
| delta_size()); |
| decoder_.StartDecoding(NULL, 0); |
| EXPECT_TRUE(decoder_.DecodeChunk(delta_data(), |
| delta_size(), |
| &result_target_)); |
| EXPECT_TRUE(decoder_.FinishDecoding()); |
| EXPECT_EQ(kTarget, result_target_); |
| } |
| |
| TEST_F(VCDiffEncoderTest, EncodeDecodeSimple) { |
| EXPECT_TRUE(simple_encoder_.Encode(kTarget, strlen(kTarget), delta())); |
| EXPECT_GE(strlen(kTarget) + kFileHeaderSize + kWindowHeaderSize, |
| delta_size()); |
| EXPECT_TRUE(simple_decoder_.Decode(kDictionary, |
| sizeof(kDictionary), |
| delta_as_const(), |
| &result_target_)); |
| EXPECT_EQ(kTarget, result_target_); |
| } |
| |
| TEST_F(VCDiffEncoderTest, EncodeDecodeInterleaved) { |
| simple_encoder_.SetFormatFlags(VCD_FORMAT_INTERLEAVED); |
| EXPECT_TRUE(simple_encoder_.Encode(kTarget, strlen(kTarget), delta())); |
| EXPECT_GE(strlen(kTarget) + kFileHeaderSize + kWindowHeaderSize, |
| delta_size()); |
| EXPECT_TRUE(simple_decoder_.Decode(kDictionary, |
| sizeof(kDictionary), |
| delta_as_const(), |
| &result_target_)); |
| EXPECT_EQ(kTarget, result_target_); |
| } |
| |
| TEST_F(VCDiffEncoderTest, EncodeDecodeInterleavedChecksum) { |
| simple_encoder_.SetFormatFlags(VCD_FORMAT_INTERLEAVED | VCD_FORMAT_CHECKSUM); |
| EXPECT_TRUE(simple_encoder_.Encode(kTarget, |
| strlen(kTarget), |
| delta())); |
| EXPECT_GE(strlen(kTarget) + kFileHeaderSize + kWindowHeaderSize, |
| delta_size()); |
| EXPECT_TRUE(simple_decoder_.Decode(kDictionary, |
| sizeof(kDictionary), |
| delta_as_const(), |
| &result_target_)); |
| EXPECT_EQ(kTarget, result_target_); |
| } |
| |
| TEST_F(VCDiffEncoderTest, EncodeDecodeSingleChunk) { |
| EXPECT_TRUE(encoder_.StartEncoding(delta())); |
| EXPECT_TRUE(encoder_.EncodeChunk(kTarget, strlen(kTarget), delta())); |
| EXPECT_TRUE(encoder_.FinishEncoding(delta())); |
| EXPECT_GE(strlen(kTarget) + kFileHeaderSize + kWindowHeaderSize, |
| delta_size()); |
| decoder_.StartDecoding(kDictionary, sizeof(kDictionary)); |
| EXPECT_TRUE(decoder_.DecodeChunk(delta_data(), |
| delta_size(), |
| &result_target_)); |
| EXPECT_TRUE(decoder_.FinishDecoding()); |
| EXPECT_EQ(kTarget, result_target_); |
| } |
| |
| TEST_F(VCDiffEncoderTest, EncodeSimpleJSON) { |
| EXPECT_TRUE(json_encoder_.StartEncoding(delta())); |
| EXPECT_TRUE(json_encoder_.EncodeChunk(kTarget, strlen(kTarget), delta())); |
| EXPECT_TRUE(json_encoder_.FinishEncoding(delta())); |
| EXPECT_EQ(kJSONDiff, delta_as_const()); |
| } |
| |
| TEST_F(VCDiffEncoderTest, EncodeSimpleExternalJSON) { |
| EXPECT_TRUE(external_encoder_.StartEncoding(delta())); |
| EXPECT_TRUE(external_encoder_.EncodeChunk(kTarget, strlen(kTarget), delta())); |
| EXPECT_TRUE(external_encoder_.FinishEncoding(delta())); |
| EXPECT_EQ(kJSONDiff, delta_as_const()); |
| } |
| |
| TEST_F(VCDiffEncoderTest, EncodeDecodeSeparate) { |
| string delta_start, delta_encode, delta_finish; |
| EXPECT_TRUE(encoder_.StartEncoding(&delta_start)); |
| EXPECT_TRUE(encoder_.EncodeChunk(kTarget, strlen(kTarget), &delta_encode)); |
| EXPECT_TRUE(encoder_.FinishEncoding(&delta_finish)); |
| EXPECT_GE(strlen(kTarget) + kFileHeaderSize + kWindowHeaderSize, |
| delta_start.size() + delta_encode.size() + delta_finish.size()); |
| decoder_.StartDecoding(kDictionary, sizeof(kDictionary)); |
| EXPECT_TRUE(decoder_.DecodeChunk(delta_start.data(), |
| delta_start.size(), |
| &result_target_)); |
| EXPECT_TRUE(decoder_.DecodeChunk(delta_encode.data(), |
| delta_encode.size(), |
| &result_target_)); |
| EXPECT_TRUE(decoder_.DecodeChunk(delta_finish.data(), |
| delta_finish.size(), |
| &result_target_)); |
| EXPECT_TRUE(decoder_.FinishDecoding()); |
| EXPECT_EQ(kTarget, result_target_); |
| } |
| |
| TEST_F(VCDiffEncoderTest, NonasciiDictionary) { |
| EXPECT_TRUE(nonascii_simple_encoder_.Encode(kTarget, |
| strlen(kTarget), |
| delta())); |
| } |
| |
| TEST_F(VCDiffEncoderTest, NonasciiDictionaryWithJSON) { |
| nonascii_simple_encoder_.SetFormatFlags(VCD_FORMAT_JSON); |
| EXPECT_FALSE(nonascii_simple_encoder_.Encode(kTarget, |
| strlen(kTarget), |
| delta())); |
| } |
| |
| TEST_F(VCDiffEncoderTest, NonasciiTarget) { |
| EXPECT_TRUE(simple_encoder_.Encode(kNonAscii, strlen(kNonAscii), delta())); |
| } |
| |
| TEST_F(VCDiffEncoderTest, NonasciiTargetWithJSON) { |
| simple_encoder_.SetFormatFlags(VCD_FORMAT_JSON); |
| EXPECT_FALSE(simple_encoder_.Encode(kNonAscii, strlen(kNonAscii), delta())); |
| } |
| |
| #ifdef HAVE_EXT_ROPE |
| // Test that the crope class can be used in place of a string for encoding |
| // and decoding. |
| TEST_F(VCDiffEncoderTest, EncodeDecodeCrope) { |
| crope delta_crope, result_crope; |
| EXPECT_TRUE(encoder_.StartEncoding(&delta_crope)); |
| EXPECT_TRUE(encoder_.EncodeChunk(kTarget, strlen(kTarget), &delta_crope)); |
| EXPECT_TRUE(encoder_.FinishEncoding(&delta_crope)); |
| EXPECT_GE(strlen(kTarget) + kFileHeaderSize + kWindowHeaderSize, |
| delta_crope.size()); |
| decoder_.StartDecoding(kDictionary, sizeof(kDictionary)); |
| // crope can't guarantee that its characters are contiguous, so the decoding |
| // has to be done byte-by-byte. |
| for (crope::const_iterator it = delta_crope.begin(); |
| it != delta_crope.end(); it++) { |
| const char this_char = *it; |
| EXPECT_TRUE(decoder_.DecodeChunk(&this_char, 1, &result_crope)); |
| } |
| EXPECT_TRUE(decoder_.FinishDecoding()); |
| crope expected_target(kTarget); |
| EXPECT_EQ(expected_target, result_crope); |
| } |
| #endif // HAVE_EXT_ROPE |
| |
| // Test the encoding and decoding with a fixed chunk size. |
| // If decoder is null, only test the encoding. |
| void VCDiffEncoderTest::TestWithFixedChunkSize(VCDiffStreamingEncoder *encoder, |
| VCDiffStreamingDecoder *decoder, |
| size_t chunk_size) { |
| delta()->clear(); |
| EXPECT_TRUE(encoder->StartEncoding(delta())); |
| for (size_t chunk_start_index = 0; |
| chunk_start_index < strlen(kTarget); |
| chunk_start_index += chunk_size) { |
| size_t this_chunk_size = chunk_size; |
| const size_t bytes_available = strlen(kTarget) - chunk_start_index; |
| if (this_chunk_size > bytes_available) { |
| this_chunk_size = bytes_available; |
| } |
| EXPECT_TRUE(encoder->EncodeChunk(&kTarget[chunk_start_index], |
| this_chunk_size, |
| delta())); |
| } |
| EXPECT_TRUE(encoder->FinishEncoding(delta())); |
| const size_t num_windows = (strlen(kTarget) / chunk_size) + 1; |
| const size_t size_of_windows = |
| strlen(kTarget) + (kWindowHeaderSize * num_windows); |
| EXPECT_GE(kFileHeaderSize + size_of_windows, delta_size()); |
| result_target_.clear(); |
| |
| if (!decoder) return; |
| |
| decoder->StartDecoding(kDictionary, sizeof(kDictionary)); |
| for (size_t chunk_start_index = 0; |
| chunk_start_index < delta_size(); |
| chunk_start_index += chunk_size) { |
| size_t this_chunk_size = chunk_size; |
| const size_t bytes_available = delta_size() - chunk_start_index; |
| if (this_chunk_size > bytes_available) { |
| this_chunk_size = bytes_available; |
| } |
| EXPECT_TRUE(decoder->DecodeChunk(delta_data() + chunk_start_index, |
| this_chunk_size, |
| &result_target_)); |
| } |
| EXPECT_TRUE(decoder->FinishDecoding()); |
| EXPECT_EQ(kTarget, result_target_); |
| } |
| |
| TEST_F(VCDiffEncoderTest, EncodeDecodeFixedChunkSizes) { |
| // These specific chunk sizes have failed in the past |
| TestWithFixedChunkSize(&encoder_, &decoder_, 6); |
| TestWithFixedChunkSize(&encoder_, &decoder_, 45); |
| TestWithFixedChunkSize(&encoder_, &decoder_, 60); |
| |
| // Now loop through all possible chunk sizes |
| for (size_t chunk_size = 1; chunk_size < strlen(kTarget); ++chunk_size) { |
| TestWithFixedChunkSize(&encoder_, &decoder_, chunk_size); |
| } |
| } |
| |
| TEST_F(VCDiffEncoderTest, EncodeFixedChunkSizesJSON) { |
| // There is no JSON decoder; these diffs are created by hand. |
| TestWithFixedChunkSize(&json_encoder_, NULL, 6); |
| EXPECT_EQ("[\"\\\"Just \",\"the pl\",\"ace fo\",\"r a Sn\",\"ark! I\"," |
| "\" have \",\"said i\",\"t twic\",\"e:\\nTha\",\"t alon\"," |
| "\"e shou\",\"ld enc\",\"ourage\",\" the c\",\"rew.\\nJ\"," |
| "\"ust th\",\"e plac\",\"e for \",\"a Snar\",\"k! I h\"," |
| "\"ave sa\",\"id it \",\"thrice\",\":\\nWhat\",\" I tel\"," |
| "\"l you \",\"three \",\"times \",\"is tru\",\"e.\\\"\\n\"]", |
| delta_as_const()); |
| TestWithFixedChunkSize(&json_encoder_, NULL, 45); |
| EXPECT_EQ("[\"\\\"Just the place for a Snark! I have said it t\"," |
| "\"wice:\\nThat alone should encourage the crew.\\nJ\"," |
| "\"ust the place for a Snark! I have said it thr\",\"ice:\\n" |
| "What I tell you three times is true.\\\"\\n\"]", |
| delta_as_const()); |
| TestWithFixedChunkSize(&json_encoder_, NULL, 60); |
| EXPECT_EQ("[\"\\\"Just the place for a Snark! I have said it twice:\\n" |
| "That alon\",\"e should encourage the crew.\\n" |
| "Just the place for a Snark! I h\",\"ave said it thrice:\\n" |
| "What I tell you three times is true.\\\"\\n\"]", |
| delta_as_const()); |
| } |
| |
| |
| // If --allow_vcd_target=false is specified, the decoder will throw away some of |
| // the internally-stored decoded target beyond the current window. Try |
| // different numbers of encoded window sizes to make sure that this behavior |
| // does not affect the results. |
| TEST_F(VCDiffEncoderTest, EncodeDecodeFixedChunkSizesNoVcdTarget) { |
| decoder_.SetAllowVcdTarget(false); |
| // Loop through all possible chunk sizes |
| for (size_t chunk_size = 1; chunk_size < strlen(kTarget); ++chunk_size) { |
| TestWithFixedChunkSize(&encoder_, &decoder_, chunk_size); |
| } |
| } |
| |
| // Splits the text to be encoded into fixed-size chunks. Encodes each |
| // chunk and puts it into a vector of strings. Then decodes each string |
| // in the vector and appends the result into result_target_. |
| void VCDiffEncoderTest::TestWithEncodedChunkVector(size_t chunk_size) { |
| std::vector<string> encoded_chunks; |
| string this_encoded_chunk; |
| size_t total_chunk_size = 0; |
| EXPECT_TRUE(encoder_.StartEncoding(&this_encoded_chunk)); |
| encoded_chunks.push_back(this_encoded_chunk); |
| total_chunk_size += this_encoded_chunk.size(); |
| for (size_t chunk_start_index = 0; |
| chunk_start_index < strlen(kTarget); |
| chunk_start_index += chunk_size) { |
| size_t this_chunk_size = chunk_size; |
| const size_t bytes_available = strlen(kTarget) - chunk_start_index; |
| if (this_chunk_size > bytes_available) { |
| this_chunk_size = bytes_available; |
| } |
| this_encoded_chunk.clear(); |
| EXPECT_TRUE(encoder_.EncodeChunk(&kTarget[chunk_start_index], |
| this_chunk_size, |
| &this_encoded_chunk)); |
| encoded_chunks.push_back(this_encoded_chunk); |
| total_chunk_size += this_encoded_chunk.size(); |
| } |
| this_encoded_chunk.clear(); |
| EXPECT_TRUE(encoder_.FinishEncoding(&this_encoded_chunk)); |
| encoded_chunks.push_back(this_encoded_chunk); |
| total_chunk_size += this_encoded_chunk.size(); |
| const size_t num_windows = (strlen(kTarget) / chunk_size) + 1; |
| const size_t size_of_windows = |
| strlen(kTarget) + (kWindowHeaderSize * num_windows); |
| EXPECT_GE(kFileHeaderSize + size_of_windows, total_chunk_size); |
| result_target_.clear(); |
| decoder_.StartDecoding(kDictionary, sizeof(kDictionary)); |
| for (std::vector<string>::iterator it = encoded_chunks.begin(); |
| it != encoded_chunks.end(); ++it) { |
| EXPECT_TRUE(decoder_.DecodeChunk(it->data(), it->size(), &result_target_)); |
| } |
| EXPECT_TRUE(decoder_.FinishDecoding()); |
| EXPECT_EQ(kTarget, result_target_); |
| } |
| |
| TEST_F(VCDiffEncoderTest, EncodeDecodeStreamOfChunks) { |
| // Loop through all possible chunk sizes |
| for (size_t chunk_size = 1; chunk_size < strlen(kTarget); ++chunk_size) { |
| TestWithEncodedChunkVector(chunk_size); |
| } |
| } |
| |
| // Verify that HashedDictionary stores a copy of the dictionary text, |
| // rather than just storing a pointer to it. If the dictionary buffer |
| // is overwritten after creating a HashedDictionary from it, it shouldn't |
| // affect an encoder that uses that HashedDictionary. |
| TEST_F(VCDiffEncoderTest, DictionaryBufferOverwritten) { |
| string dictionary_copy(kDictionary, sizeof(kDictionary)); |
| HashedDictionary hd_copy(dictionary_copy.data(), dictionary_copy.size()); |
| EXPECT_TRUE(hd_copy.Init()); |
| VCDiffStreamingEncoder copy_encoder(&hd_copy, |
| VCD_FORMAT_INTERLEAVED |
| | VCD_FORMAT_CHECKSUM, |
| /* look_for_target_matches = */ true); |
| // Produce a reference version of the encoded text. |
| string delta_before; |
| EXPECT_TRUE(copy_encoder.StartEncoding(&delta_before)); |
| EXPECT_TRUE(copy_encoder.EncodeChunk(kTarget, |
| strlen(kTarget), |
| &delta_before)); |
| EXPECT_TRUE(copy_encoder.FinishEncoding(&delta_before)); |
| EXPECT_GE(strlen(kTarget) + kFileHeaderSize + kWindowHeaderSize, |
| delta_before.size()); |
| |
| // Overwrite the dictionary text with all 'Q' characters. |
| dictionary_copy.replace(0, |
| dictionary_copy.size(), |
| dictionary_copy.size(), |
| 'Q'); |
| // When the encoder is used on the same target text after overwriting |
| // the dictionary, it should produce the same encoded output. |
| string delta_after; |
| EXPECT_TRUE(copy_encoder.StartEncoding(&delta_after)); |
| EXPECT_TRUE(copy_encoder.EncodeChunk(kTarget, strlen(kTarget), &delta_after)); |
| EXPECT_TRUE(copy_encoder.FinishEncoding(&delta_after)); |
| EXPECT_EQ(delta_before, delta_after); |
| } |
| |
| // Binary data test part 1: The dictionary and target data should not |
| // be treated as NULL-terminated. An embedded NULL should be handled like |
| // any other byte of data. |
| TEST_F(VCDiffEncoderTest, DictionaryHasEmbeddedNULLs) { |
| const char embedded_null_dictionary_text[] = |
| { 0x00, 0xFF, 0xFE, 0xFD, 0x00, 0xFD, 0xFE, 0xFF, 0x00, 0x03 }; |
| const char embedded_null_target[] = |
| { 0xFD, 0x00, 0xFD, 0xFE, 0x03, 0x00, 0x01, 0x00 }; |
| CHECK_EQ(10, sizeof(embedded_null_dictionary_text)); |
| CHECK_EQ(8, sizeof(embedded_null_target)); |
| HashedDictionary embedded_null_dictionary(embedded_null_dictionary_text, |
| sizeof(embedded_null_dictionary_text)); |
| EXPECT_TRUE(embedded_null_dictionary.Init()); |
| VCDiffStreamingEncoder embedded_null_encoder(&embedded_null_dictionary, |
| VCD_FORMAT_INTERLEAVED | VCD_FORMAT_CHECKSUM, |
| /* look_for_target_matches = */ true); |
| EXPECT_TRUE(embedded_null_encoder.StartEncoding(delta())); |
| EXPECT_TRUE(embedded_null_encoder.EncodeChunk(embedded_null_target, |
| sizeof(embedded_null_target), |
| delta())); |
| EXPECT_TRUE(embedded_null_encoder.FinishEncoding(delta())); |
| decoder_.StartDecoding(embedded_null_dictionary_text, |
| sizeof(embedded_null_dictionary_text)); |
| EXPECT_TRUE(decoder_.DecodeChunk(delta_data(), |
| delta_size(), |
| &result_target_)); |
| EXPECT_TRUE(decoder_.FinishDecoding()); |
| EXPECT_EQ(sizeof(embedded_null_target), result_target_.size()); |
| EXPECT_EQ(string(embedded_null_target, |
| sizeof(embedded_null_target)), |
| result_target_); |
| } |
| |
| // Binary data test part 2: An embedded CR or LF should be handled like |
| // any other byte of data. No text-processing of the data should occur. |
| TEST_F(VCDiffEncoderTest, DictionaryHasEmbeddedNewlines) { |
| const char embedded_null_dictionary_text[] = |
| { 0x0C, 0xFF, 0xFE, 0x0C, 0x00, 0x0A, 0xFE, 0xFF, 0x00, 0x0A }; |
| const char embedded_null_target[] = |
| { 0x0C, 0x00, 0x0A, 0xFE, 0x03, 0x00, 0x0A, 0x00 }; |
| CHECK_EQ(10, sizeof(embedded_null_dictionary_text)); |
| CHECK_EQ(8, sizeof(embedded_null_target)); |
| HashedDictionary embedded_null_dictionary(embedded_null_dictionary_text, |
| sizeof(embedded_null_dictionary_text)); |
| EXPECT_TRUE(embedded_null_dictionary.Init()); |
| VCDiffStreamingEncoder embedded_null_encoder(&embedded_null_dictionary, |
| VCD_FORMAT_INTERLEAVED | VCD_FORMAT_CHECKSUM, |
| /* look_for_target_matches = */ true); |
| EXPECT_TRUE(embedded_null_encoder.StartEncoding(delta())); |
| EXPECT_TRUE(embedded_null_encoder.EncodeChunk(embedded_null_target, |
| sizeof(embedded_null_target), |
| delta())); |
| EXPECT_TRUE(embedded_null_encoder.FinishEncoding(delta())); |
| decoder_.StartDecoding(embedded_null_dictionary_text, |
| sizeof(embedded_null_dictionary_text)); |
| EXPECT_TRUE(decoder_.DecodeChunk(delta_data(), |
| delta_size(), |
| &result_target_)); |
| EXPECT_TRUE(decoder_.FinishDecoding()); |
| EXPECT_EQ(sizeof(embedded_null_target), result_target_.size()); |
| EXPECT_EQ(string(embedded_null_target, |
| sizeof(embedded_null_target)), |
| result_target_); |
| } |
| |
| TEST_F(VCDiffEncoderTest, UsingWideCharacters) { |
| const wchar_t wchar_dictionary_text[] = |
| L"\"Just the place for a Snark!\" the Bellman cried,\n" |
| L"As he landed his crew with care;\n" |
| L"Supporting each man on the top of the tide\n" |
| L"By a finger entwined in his hair.\n"; |
| |
| const wchar_t wchar_target[] = |
| L"\"Just the place for a Snark! I have said it twice:\n" |
| L"That alone should encourage the crew.\n" |
| L"Just the place for a Snark! I have said it thrice:\n" |
| L"What I tell you three times is true.\"\n"; |
| |
| HashedDictionary wchar_dictionary((const char*) wchar_dictionary_text, |
| sizeof(wchar_dictionary_text)); |
| EXPECT_TRUE(wchar_dictionary.Init()); |
| VCDiffStreamingEncoder wchar_encoder(&wchar_dictionary, |
| VCD_FORMAT_INTERLEAVED |
| | VCD_FORMAT_CHECKSUM, |
| /* look_for_target_matches = */ false); |
| EXPECT_TRUE(wchar_encoder.StartEncoding(delta())); |
| EXPECT_TRUE(wchar_encoder.EncodeChunk((const char*) wchar_target, |
| sizeof(wchar_target), |
| delta())); |
| EXPECT_TRUE(wchar_encoder.FinishEncoding(delta())); |
| decoder_.StartDecoding((const char*) wchar_dictionary_text, |
| sizeof(wchar_dictionary_text)); |
| EXPECT_TRUE(decoder_.DecodeChunk(delta_data(), |
| delta_size(), |
| &result_target_)); |
| EXPECT_TRUE(decoder_.FinishDecoding()); |
| const wchar_t* result_as_wchar = (const wchar_t*) result_target_.data(); |
| EXPECT_EQ(wcslen(wchar_target), wcslen(result_as_wchar)); |
| EXPECT_EQ(0, wcscmp(wchar_target, result_as_wchar)); |
| } |
| |
| #if defined(HAVE_MPROTECT) && \ |
| (defined(HAVE_MEMALIGN) || defined(HAVE_POSIX_MEMALIGN)) |
| // Bug 1220602: Make sure the encoder doesn't read past the end of the input |
| // buffer. |
| TEST_F(VCDiffEncoderTest, ShouldNotReadPastEndOfBuffer) { |
| const size_t target_size = strlen(kTarget); |
| |
| // Allocate two memory pages. |
| const int page_size = getpagesize(); |
| void* two_pages = NULL; |
| #ifdef HAVE_POSIX_MEMALIGN |
| posix_memalign(&two_pages, page_size, 2 * page_size); |
| #else // !HAVE_POSIX_MEMALIGN |
| two_pages = memalign(page_size, 2 * page_size); |
| #endif // HAVE_POSIX_MEMALIGN |
| char* const first_page = reinterpret_cast<char*>(two_pages); |
| char* const second_page = first_page + page_size; |
| |
| // Place the target string at the end of the first page. |
| char* const target_with_guard = second_page - target_size; |
| memcpy(target_with_guard, kTarget, target_size); |
| |
| // Make the second page unreadable. |
| mprotect(second_page, page_size, PROT_NONE); |
| |
| // Now perform the encode operation, which will cause a segmentation fault |
| // if it reads past the end of the buffer. |
| EXPECT_TRUE(encoder_.StartEncoding(delta())); |
| EXPECT_TRUE(encoder_.EncodeChunk(target_with_guard, target_size, delta())); |
| EXPECT_TRUE(encoder_.FinishEncoding(delta())); |
| |
| // Undo the mprotect. |
| mprotect(second_page, page_size, PROT_READ|PROT_WRITE); |
| free(two_pages); |
| } |
| |
| TEST_F(VCDiffEncoderTest, ShouldNotReadPastBeginningOfBuffer) { |
| const size_t target_size = strlen(kTarget); |
| |
| // Allocate two memory pages. |
| const int page_size = getpagesize(); |
| void* two_pages = NULL; |
| #ifdef HAVE_POSIX_MEMALIGN |
| posix_memalign(&two_pages, page_size, 2 * page_size); |
| #else // !HAVE_POSIX_MEMALIGN |
| two_pages = memalign(page_size, 2 * page_size); |
| #endif // HAVE_POSIX_MEMALIGN |
| char* const first_page = reinterpret_cast<char*>(two_pages); |
| char* const second_page = first_page + page_size; |
| |
| // Make the first page unreadable. |
| mprotect(first_page, page_size, PROT_NONE); |
| |
| // Place the target string at the beginning of the second page. |
| char* const target_with_guard = second_page; |
| memcpy(target_with_guard, kTarget, target_size); |
| |
| // Now perform the encode operation, which will cause a segmentation fault |
| // if it reads past the beginning of the buffer. |
| EXPECT_TRUE(encoder_.StartEncoding(delta())); |
| EXPECT_TRUE(encoder_.EncodeChunk(target_with_guard, target_size, delta())); |
| EXPECT_TRUE(encoder_.FinishEncoding(delta())); |
| |
| // Undo the mprotect. |
| mprotect(first_page, page_size, PROT_READ|PROT_WRITE); |
| free(two_pages); |
| } |
| #endif // HAVE_MPROTECT && (HAVE_MEMALIGN || HAVE_POSIX_MEMALIGN) |
| |
| class VCDiffHTML1Test : public VerifyEncodedBytesTest { |
| protected: |
| static const char kDictionary[]; |
| static const char kTarget[]; |
| static const char kRedundantTarget[]; |
| |
| VCDiffHTML1Test(); |
| virtual ~VCDiffHTML1Test() { } |
| |
| void SimpleEncode(); |
| void StreamingEncode(); |
| |
| HashedDictionary hashed_dictionary_; |
| VCDiffStreamingEncoder encoder_; |
| VCDiffStreamingDecoder decoder_; |
| VCDiffEncoder simple_encoder_; |
| VCDiffDecoder simple_decoder_; |
| |
| string result_target_; |
| }; |
| |
| const char VCDiffHTML1Test::kDictionary[] = |
| "<html><font color=red>This part from the dict</font><br>"; |
| |
| const char VCDiffHTML1Test::kTarget[] = |
| "<html><font color=red>This part from the dict</font><br>\n" |
| "And this part is not...</html>"; |
| |
| const char VCDiffHTML1Test::kRedundantTarget[] = |
| "AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA" |
| "AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA" |
| "AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA" |
| "AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"; // 256 |
| |
| VCDiffHTML1Test::VCDiffHTML1Test() |
| : hashed_dictionary_(kDictionary, sizeof(kDictionary)), |
| encoder_(&hashed_dictionary_, |
| VCD_FORMAT_INTERLEAVED | VCD_FORMAT_CHECKSUM, |
| /* look_for_target_matches = */ true), |
| simple_encoder_(kDictionary, sizeof(kDictionary)) { |
| EXPECT_TRUE(hashed_dictionary_.Init()); |
| } |
| |
| void VCDiffHTML1Test::SimpleEncode() { |
| EXPECT_TRUE(simple_encoder_.Encode(kTarget, strlen(kTarget), delta())); |
| EXPECT_GE(strlen(kTarget) + kFileHeaderSize + kWindowHeaderSize, |
| delta_size()); |
| EXPECT_TRUE(simple_decoder_.Decode(kDictionary, |
| sizeof(kDictionary), |
| delta_as_const(), |
| &result_target_)); |
| EXPECT_EQ(kTarget, result_target_); |
| } |
| |
| void VCDiffHTML1Test::StreamingEncode() { |
| EXPECT_TRUE(encoder_.StartEncoding(delta())); |
| EXPECT_TRUE(encoder_.EncodeChunk(kTarget, strlen(kTarget), delta())); |
| EXPECT_TRUE(encoder_.FinishEncoding(delta())); |
| } |
| |
| TEST_F(VCDiffHTML1Test, CheckOutputOfSimpleEncoder) { |
| SimpleEncode(); |
| // These values do not depend on the block size used for encoding |
| ExpectByte(0xD6); // 'V' | 0x80 |
| ExpectByte(0xC3); // 'C' | 0x80 |
| ExpectByte(0xC4); // 'D' | 0x80 |
| ExpectByte(0x00); // Simple encoder never uses interleaved format |
| ExpectByte(0x00); // Hdr_Indicator |
| ExpectByte(VCD_SOURCE); // Win_Indicator: VCD_SOURCE (dictionary) |
| ExpectByte(sizeof(kDictionary)); // Dictionary length |
| ExpectByte(0x00); // Source segment position: start of dictionary |
| if (BlockHash::kBlockSize < 16) { |
| // A medium block size will catch the "his part " match. |
| ExpectByte(0x22); // Length of the delta encoding |
| ExpectSize(strlen(kTarget)); // Size of the target window |
| ExpectByte(0x00); // Delta_indicator (no compression) |
| ExpectByte(0x16); // Length of the data section |
| ExpectByte(0x05); // Length of the instructions section |
| ExpectByte(0x02); // Length of the address section |
| // Data section |
| ExpectString("\nAnd t"); // Data for 1st ADD |
| ExpectString("is not...</html>"); // Data for 2nd ADD |
| // Instructions section |
| ExpectByte(0x73); // COPY size 0 mode VCD_SAME(0) |
| ExpectByte(0x38); // COPY size (56) |
| ExpectByte(0x07); // ADD size 6 |
| ExpectByte(0x19); // COPY size 9 mode VCD_SELF |
| ExpectByte(0x11); // ADD size 16 |
| // Address section |
| ExpectByte(0x00); // COPY address (0) mode VCD_SAME(0) |
| ExpectByte(0x17); // COPY address (23) mode VCD_SELF |
| } else if (BlockHash::kBlockSize <= 56) { |
| // Any block size up to 56 will catch the matching prefix string. |
| ExpectByte(0x29); // Length of the delta encoding |
| ExpectSize(strlen(kTarget)); // Size of the target window |
| ExpectByte(0x00); // Delta_indicator (no compression) |
| ExpectByte(0x1F); // Length of the data section |
| ExpectByte(0x04); // Length of the instructions section |
| ExpectByte(0x01); // Length of the address section |
| ExpectString("\nAnd this part is not...</html>"); // Data for ADD |
| // Instructions section |
| ExpectByte(0x73); // COPY size 0 mode VCD_SAME(0) |
| ExpectByte(0x38); // COPY size (56) |
| ExpectByte(0x01); // ADD size 0 |
| ExpectByte(0x1F); // Size of ADD (31) |
| // Address section |
| ExpectByte(0x00); // COPY address (0) mode VCD_SAME(0) |
| } else { |
| // The matching string is 56 characters long, and the block size is |
| // 64 or greater, so no match should be found. |
| ExpectSize(strlen(kTarget) + 7); // Delta encoding len |
| ExpectSize(strlen(kTarget)); // Size of the target window |
| ExpectByte(0x00); // Delta_indicator (no compression) |
| ExpectSize(strlen(kTarget)); // Length of the data section |
| ExpectByte(0x02); // Length of the instructions section |
| ExpectByte(0x00); // Length of the address section |
| // Data section |
| ExpectString(kTarget); |
| ExpectByte(0x01); // ADD size 0 |
| ExpectSize(strlen(kTarget)); |
| } |
| ExpectNoMoreBytes(); |
| } |
| |
| TEST_F(VCDiffHTML1Test, SimpleEncoderPerformsTargetMatching) { |
| EXPECT_TRUE(simple_encoder_.Encode(kRedundantTarget, |
| strlen(kRedundantTarget), |
| delta())); |
| EXPECT_GE(strlen(kRedundantTarget) + kFileHeaderSize + kWindowHeaderSize, |
| delta_size()); |
| EXPECT_TRUE(simple_decoder_.Decode(kDictionary, |
| sizeof(kDictionary), |
| delta_as_const(), |
| &result_target_)); |
| EXPECT_EQ(kRedundantTarget, result_target_); |
| // These values do not depend on the block size used for encoding |
| ExpectByte(0xD6); // 'V' | 0x80 |
| ExpectByte(0xC3); // 'C' | 0x80 |
| ExpectByte(0xC4); // 'D' | 0x80 |
| ExpectByte(0x00); // Simple encoder never uses interleaved format |
| ExpectByte(0x00); // Hdr_Indicator |
| ExpectByte(VCD_SOURCE); // Win_Indicator: VCD_SOURCE (dictionary) |
| ExpectByte(sizeof(kDictionary)); // Dictionary length |
| ExpectByte(0x00); // Source segment position: start of dictionary |
| ExpectByte(0x0C); // Length of the delta encoding |
| ExpectSize(strlen(kRedundantTarget)); // Size of the target window |
| ExpectByte(0x00); // Delta_indicator (no compression) |
| ExpectByte(0x01); // Length of the data section |
| ExpectByte(0x04); // Length of the instructions section |
| ExpectByte(0x01); // Length of the address section |
| // Data section |
| ExpectString("A"); // Data for ADD |
| // Instructions section |
| ExpectByte(0x02); // ADD size 1 |
| ExpectByte(0x23); // COPY size 0 mode VCD_HERE |
| ExpectSize(strlen(kRedundantTarget) - 1); // COPY size 255 |
| // Address section |
| ExpectByte(0x01); // COPY address (1) mode VCD_HERE |
| ExpectNoMoreBytes(); |
| } |
| |
| TEST_F(VCDiffHTML1Test, SimpleEncoderWithoutTargetMatching) { |
| simple_encoder_.SetTargetMatching(false); |
| EXPECT_TRUE(simple_encoder_.Encode(kRedundantTarget, |
| strlen(kRedundantTarget), |
| delta())); |
| EXPECT_GE(strlen(kRedundantTarget) + kFileHeaderSize + kWindowHeaderSize, |
| delta_size()); |
| EXPECT_TRUE(simple_decoder_.Decode(kDictionary, |
| sizeof(kDictionary), |
| delta_as_const(), |
| &result_target_)); |
| EXPECT_EQ(kRedundantTarget, result_target_); |
| // These values do not depend on the block size used for encoding |
| ExpectByte(0xD6); // 'V' | 0x80 |
| ExpectByte(0xC3); // 'C' | 0x80 |
| ExpectByte(0xC4); // 'D' | 0x80 |
| ExpectByte(0x00); // Simple encoder never uses interleaved format |
| ExpectByte(0x00); // Hdr_Indicator |
| ExpectByte(VCD_SOURCE); // Win_Indicator: VCD_SOURCE (dictionary) |
| ExpectByte(sizeof(kDictionary)); // Dictionary length |
| ExpectByte(0x00); // Source segment position: start of dictionary |
| ExpectSize(strlen(kRedundantTarget) + 0x0A); // Length of the delta encoding |
| ExpectSize(strlen(kRedundantTarget)); // Size of the target window |
| ExpectByte(0x00); // Delta_indicator (no compression) |
| ExpectSize(strlen(kRedundantTarget)); // Length of the data section |
| ExpectByte(0x03); // Length of the instructions section |
| ExpectByte(0x00); // Length of the address section |
| // Data section |
| ExpectString(kRedundantTarget); // Data for ADD |
| // Instructions section |
| ExpectByte(0x01); // ADD size 0 |
| ExpectSize(strlen(kRedundantTarget)); // ADD size |
| // Address section empty |
| ExpectNoMoreBytes(); |
| } |
| |
| class VCDiffHTML2Test : public VerifyEncodedBytesTest { |
| protected: |
| static const char kDictionary[]; |
| static const char kTarget[]; |
| |
| VCDiffHTML2Test(); |
| virtual ~VCDiffHTML2Test() { } |
| |
| void SimpleEncode(); |
| void StreamingEncode(); |
| |
| HashedDictionary hashed_dictionary_; |
| VCDiffStreamingEncoder encoder_; |
| VCDiffStreamingDecoder decoder_; |
| VCDiffEncoder simple_encoder_; |
| VCDiffDecoder simple_decoder_; |
| |
| string result_target_; |
| }; |
| |
| const char VCDiffHTML2Test::kDictionary[] = "10\nThis is a test"; |
| |
| const char VCDiffHTML2Test::kTarget[] = "This is a test!!!\n"; |
| |
| VCDiffHTML2Test::VCDiffHTML2Test() |
| : hashed_dictionary_(kDictionary, sizeof(kDictionary)), |
| encoder_(&hashed_dictionary_, |
| VCD_FORMAT_INTERLEAVED | VCD_FORMAT_CHECKSUM, |
| /* look_for_target_matches = */ true), |
| simple_encoder_(kDictionary, sizeof(kDictionary)) { |
| EXPECT_TRUE(hashed_dictionary_.Init()); |
| } |
| |
| void VCDiffHTML2Test::SimpleEncode() { |
| EXPECT_TRUE(simple_encoder_.Encode(kTarget, strlen(kTarget), delta())); |
| EXPECT_GE(strlen(kTarget) + kFileHeaderSize + kWindowHeaderSize, |
| delta_size()); |
| EXPECT_TRUE(simple_decoder_.Decode(kDictionary, |
| sizeof(kDictionary), |
| delta_as_const(), |
| &result_target_)); |
| EXPECT_EQ(kTarget, result_target_); |
| } |
| |
| void VCDiffHTML2Test::StreamingEncode() { |
| EXPECT_TRUE(encoder_.StartEncoding(delta())); |
| EXPECT_TRUE(encoder_.EncodeChunk(kTarget, strlen(kTarget), delta())); |
| EXPECT_GE(strlen(kTarget) + kFileHeaderSize + kWindowHeaderSize, |
| delta_size()); |
| EXPECT_TRUE(simple_decoder_.Decode(kDictionary, |
| sizeof(kDictionary), |
| delta_as_const(), |
| &result_target_)); |
| EXPECT_EQ(kTarget, result_target_); |
| } |
| |
| TEST_F(VCDiffHTML2Test, VerifyOutputOfSimpleEncoder) { |
| SimpleEncode(); |
| // These values do not depend on the block size used for encoding |
| ExpectByte(0xD6); // 'V' | 0x80 |
| ExpectByte(0xC3); // 'C' | 0x80 |
| ExpectByte(0xC4); // 'D' | 0x80 |
| ExpectByte(0x00); // Simple encoder never uses interleaved format |
| ExpectByte(0x00); // Hdr_Indicator |
| ExpectByte(VCD_SOURCE); // Win_Indicator: VCD_SOURCE (dictionary) |
| ExpectByte(sizeof(kDictionary)); // Dictionary length |
| ExpectByte(0x00); // Source segment position: start of dictionary |
| if (BlockHash::kBlockSize <= 8) { |
| ExpectByte(12); // Length of the delta encoding |
| ExpectSize(strlen(kTarget)); // Size of the target window |
| ExpectByte(0x00); // Delta_indicator (no compression) |
| ExpectByte(0x04); // Length of the data section |
| ExpectByte(0x02); // Length of the instructions section |
| ExpectByte(0x01); // Length of the address section |
| ExpectByte('!'); |
| ExpectByte('!'); |
| ExpectByte('!'); |
| ExpectByte('\n'); |
| ExpectByte(0x1E); // COPY size 14 mode VCD_SELF |
| ExpectByte(0x05); // ADD size 4 |
| ExpectByte(0x03); // COPY address (3) mode VCD_SELF |
| } else { |
| // Larger block sizes will not catch any matches. |
| ExpectSize(strlen(kTarget) + 7); // Delta encoding len |
| ExpectSize(strlen(kTarget)); // Size of the target window |
| ExpectByte(0x00); // Delta_indicator (no compression) |
| ExpectSize(strlen(kTarget)); // Length of the data section |
| ExpectByte(0x02); // Length of the instructions section |
| ExpectByte(0x00); // Length of the address section |
| // Data section |
| ExpectString(kTarget); |
| ExpectByte(0x01); // ADD size 0 |
| ExpectSize(strlen(kTarget)); |
| } |
| ExpectNoMoreBytes(); |
| } |
| |
| TEST_F(VCDiffHTML2Test, VerifyOutputWithChecksum) { |
| StreamingEncode(); |
| const VCDChecksum html2_checksum = ComputeAdler32(kTarget, strlen(kTarget)); |
| CHECK_EQ(5, VarintBE<int64_t>::Length(html2_checksum)); |
| // These values do not depend on the block size used for encoding |
| ExpectByte(0xD6); // 'V' | 0x80 |
| ExpectByte(0xC3); // 'C' | 0x80 |
| ExpectByte(0xC4); // 'D' | 0x80 |
| ExpectByte('S'); // Format extensions |
| ExpectByte(0x00); // Hdr_Indicator |
| ExpectByte(VCD_SOURCE | VCD_CHECKSUM); // Win_Indicator |
| ExpectByte(sizeof(kDictionary)); // Dictionary length |
| ExpectByte(0x00); // Source segment position: start of dictionary |
| if (BlockHash::kBlockSize <= 8) { |
| ExpectByte(17); // Length of the delta encoding |
| ExpectSize(strlen(kTarget)); // Size of the target window |
| ExpectByte(0x00); // Delta_indicator (no compression) |
| ExpectByte(0x00); // Length of the data section |
| ExpectByte(0x07); // Length of the instructions section |
| ExpectByte(0x00); // Length of the address section |
| ExpectChecksum(html2_checksum); |
| ExpectByte(0x1E); // COPY size 14 mode VCD_SELF |
| ExpectByte(0x03); // COPY address (3) mode VCD_SELF |
| ExpectByte(0x05); // ADD size 4 |
| ExpectByte('!'); |
| ExpectByte('!'); |
| ExpectByte('!'); |
| ExpectByte('\n'); |
| } else { |
| // Larger block sizes will not catch any matches. |
| ExpectSize(strlen(kTarget) + 12); // Delta encoding len |
| ExpectSize(strlen(kTarget)); // Size of the target window |
| ExpectByte(0x00); // Delta_indicator (no compression) |
| ExpectByte(0x00); // Length of the data section |
| ExpectSize(0x02 + strlen(kTarget)); // Interleaved |
| ExpectByte(0x00); // Length of the address section |
| ExpectChecksum(html2_checksum); |
| // Data section |
| ExpectByte(0x01); // ADD size 0 |
| ExpectSize(strlen(kTarget)); |
| ExpectString(kTarget); |
| } |
| ExpectNoMoreBytes(); |
| } |
| |
| } // anonymous namespace |
| } // namespace open_vcdiff |
