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Diffstat (limited to 'app/snappy/snappy_unittest.cc')
| -rw-r--r-- | app/snappy/snappy_unittest.cc | 1164 |
1 files changed, 1164 insertions, 0 deletions
diff --git a/app/snappy/snappy_unittest.cc b/app/snappy/snappy_unittest.cc new file mode 100644 index 00000000..59c108f4 --- /dev/null +++ b/app/snappy/snappy_unittest.cc @@ -0,0 +1,1164 @@ +// Copyright 2005 and onwards Google Inc. +// +// Redistribution and use in source and binary forms, with or without +// modification, are permitted provided that the following conditions are +// met: +// +// * Redistributions of source code must retain the above copyright +// notice, this list of conditions and the following disclaimer. +// * Redistributions in binary form must reproduce the above +// copyright notice, this list of conditions and the following disclaimer +// in the documentation and/or other materials provided with the +// distribution. +// * Neither the name of Google Inc. nor the names of its +// contributors may be used to endorse or promote products derived from +// this software without specific prior written permission. +// +// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + +#include <math.h> +#include <stdlib.h> + + +#include <algorithm> +#include <string> +#include <vector> + +#include "snappy.h" +#include "snappy-internal.h" +#include "snappy-test.h" +#include "snappy-sinksource.h" + +DEFINE_int32(start_len, -1, + "Starting prefix size for testing (-1: just full file contents)"); +DEFINE_int32(end_len, -1, + "Starting prefix size for testing (-1: just full file contents)"); +DEFINE_int32(bytes, 10485760, + "How many bytes to compress/uncompress per file for timing"); + +DEFINE_bool(zlib, false, + "Run zlib compression (http://www.zlib.net)"); +DEFINE_bool(lzo, false, + "Run LZO compression (http://www.oberhumer.com/opensource/lzo/)"); +DEFINE_bool(quicklz, false, + "Run quickLZ compression (http://www.quicklz.com/)"); +DEFINE_bool(liblzf, false, + "Run libLZF compression " + "(http://www.goof.com/pcg/marc/liblzf.html)"); +DEFINE_bool(fastlz, false, + "Run FastLZ compression (http://www.fastlz.org/"); +DEFINE_bool(snappy, true, "Run snappy compression"); + + +DEFINE_bool(write_compressed, false, + "Write compressed versions of each file to <file>.comp"); +DEFINE_bool(write_uncompressed, false, + "Write uncompressed versions of each file to <file>.uncomp"); + +namespace snappy { + + +#ifdef HAVE_FUNC_MMAP + +// To test against code that reads beyond its input, this class copies a +// string to a newly allocated group of pages, the last of which +// is made unreadable via mprotect. Note that we need to allocate the +// memory with mmap(), as POSIX allows mprotect() only on memory allocated +// with mmap(), and some malloc/posix_memalign implementations expect to +// be able to read previously allocated memory while doing heap allocations. +class DataEndingAtUnreadablePage { + public: + explicit DataEndingAtUnreadablePage(const string& s) { + const size_t page_size = getpagesize(); + const size_t size = s.size(); + // Round up space for string to a multiple of page_size. + size_t space_for_string = (size + page_size - 1) & ~(page_size - 1); + alloc_size_ = space_for_string + page_size; + mem_ = mmap(NULL, alloc_size_, + PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0); + CHECK_NE(MAP_FAILED, mem_); + protected_page_ = reinterpret_cast<char*>(mem_) + space_for_string; + char* dst = protected_page_ - size; + memcpy(dst, s.data(), size); + data_ = dst; + size_ = size; + // Make guard page unreadable. + CHECK_EQ(0, mprotect(protected_page_, page_size, PROT_NONE)); + } + + ~DataEndingAtUnreadablePage() { + // Undo the mprotect. + CHECK_EQ(0, mprotect(protected_page_, getpagesize(), PROT_READ|PROT_WRITE)); + CHECK_EQ(0, munmap(mem_, alloc_size_)); + } + + const char* data() const { return data_; } + size_t size() const { return size_; } + + private: + size_t alloc_size_; + void* mem_; + char* protected_page_; + const char* data_; + size_t size_; +}; + +#else // HAVE_FUNC_MMAP + +// Fallback for systems without mmap. +typedef string DataEndingAtUnreadablePage; + +#endif + +enum CompressorType { + ZLIB, LZO, LIBLZF, QUICKLZ, FASTLZ, SNAPPY +}; + +const char* names[] = { + "ZLIB", "LZO", "LIBLZF", "QUICKLZ", "FASTLZ", "SNAPPY" +}; + +static size_t MinimumRequiredOutputSpace(size_t input_size, + CompressorType comp) { + switch (comp) { +#ifdef ZLIB_VERSION + case ZLIB: + return ZLib::MinCompressbufSize(input_size); +#endif // ZLIB_VERSION + +#ifdef LZO_VERSION + case LZO: + return input_size + input_size/64 + 16 + 3; +#endif // LZO_VERSION + +#ifdef LZF_VERSION + case LIBLZF: + return input_size; +#endif // LZF_VERSION + +#ifdef QLZ_VERSION_MAJOR + case QUICKLZ: + return input_size + 36000; // 36000 is used for scratch. +#endif // QLZ_VERSION_MAJOR + +#ifdef FASTLZ_VERSION + case FASTLZ: + return max(static_cast<int>(ceil(input_size * 1.05)), 66); +#endif // FASTLZ_VERSION + + case SNAPPY: + return snappy::MaxCompressedLength(input_size); + + default: + LOG(FATAL) << "Unknown compression type number " << comp; + } +} + +// Returns true if we successfully compressed, false otherwise. +// +// If compressed_is_preallocated is set, do not resize the compressed buffer. +// This is typically what you want for a benchmark, in order to not spend +// time in the memory allocator. If you do set this flag, however, +// "compressed" must be preinitialized to at least MinCompressbufSize(comp) +// number of bytes, and may contain junk bytes at the end after return. +static bool Compress(const char* input, size_t input_size, CompressorType comp, + string* compressed, bool compressed_is_preallocated) { + if (!compressed_is_preallocated) { + compressed->resize(MinimumRequiredOutputSpace(input_size, comp)); + } + + switch (comp) { +#ifdef ZLIB_VERSION + case ZLIB: { + ZLib zlib; + uLongf destlen = compressed->size(); + int ret = zlib.Compress( + reinterpret_cast<Bytef*>(string_as_array(compressed)), + &destlen, + reinterpret_cast<const Bytef*>(input), + input_size); + CHECK_EQ(Z_OK, ret); + if (!compressed_is_preallocated) { + compressed->resize(destlen); + } + return true; + } +#endif // ZLIB_VERSION + +#ifdef LZO_VERSION + case LZO: { + unsigned char* mem = new unsigned char[LZO1X_1_15_MEM_COMPRESS]; + lzo_uint destlen; + int ret = lzo1x_1_15_compress( + reinterpret_cast<const uint8*>(input), + input_size, + reinterpret_cast<uint8*>(string_as_array(compressed)), + &destlen, + mem); + CHECK_EQ(LZO_E_OK, ret); + delete[] mem; + if (!compressed_is_preallocated) { + compressed->resize(destlen); + } + break; + } +#endif // LZO_VERSION + +#ifdef LZF_VERSION + case LIBLZF: { + int destlen = lzf_compress(input, + input_size, + string_as_array(compressed), + input_size); + if (destlen == 0) { + // lzf *can* cause lots of blowup when compressing, so they + // recommend to limit outsize to insize, and just not compress + // if it's bigger. Ideally, we'd just swap input and output. + compressed->assign(input, input_size); + destlen = input_size; + } + if (!compressed_is_preallocated) { + compressed->resize(destlen); + } + break; + } +#endif // LZF_VERSION + +#ifdef QLZ_VERSION_MAJOR + case QUICKLZ: { + qlz_state_compress *state_compress = new qlz_state_compress; + int destlen = qlz_compress(input, + string_as_array(compressed), + input_size, + state_compress); + delete state_compress; + CHECK_NE(0, destlen); + if (!compressed_is_preallocated) { + compressed->resize(destlen); + } + break; + } +#endif // QLZ_VERSION_MAJOR + +#ifdef FASTLZ_VERSION + case FASTLZ: { + // Use level 1 compression since we mostly care about speed. + int destlen = fastlz_compress_level( + 1, + input, + input_size, + string_as_array(compressed)); + if (!compressed_is_preallocated) { + compressed->resize(destlen); + } + CHECK_NE(destlen, 0); + break; + } +#endif // FASTLZ_VERSION + + case SNAPPY: { + size_t destlen; + snappy::RawCompress(input, input_size, + string_as_array(compressed), + &destlen); + CHECK_LE(destlen, snappy::MaxCompressedLength(input_size)); + if (!compressed_is_preallocated) { + compressed->resize(destlen); + } + break; + } + + + default: { + return false; // the asked-for library wasn't compiled in + } + } + return true; +} + +static bool Uncompress(const string& compressed, CompressorType comp, + int size, string* output) { + switch (comp) { +#ifdef ZLIB_VERSION + case ZLIB: { + output->resize(size); + ZLib zlib; + uLongf destlen = output->size(); + int ret = zlib.Uncompress( + reinterpret_cast<Bytef*>(string_as_array(output)), + &destlen, + reinterpret_cast<const Bytef*>(compressed.data()), + compressed.size()); + CHECK_EQ(Z_OK, ret); + CHECK_EQ(static_cast<uLongf>(size), destlen); + break; + } +#endif // ZLIB_VERSION + +#ifdef LZO_VERSION + case LZO: { + output->resize(size); + lzo_uint destlen; + int ret = lzo1x_decompress( + reinterpret_cast<const uint8*>(compressed.data()), + compressed.size(), + reinterpret_cast<uint8*>(string_as_array(output)), + &destlen, + NULL); + CHECK_EQ(LZO_E_OK, ret); + CHECK_EQ(static_cast<lzo_uint>(size), destlen); + break; + } +#endif // LZO_VERSION + +#ifdef LZF_VERSION + case LIBLZF: { + output->resize(size); + int destlen = lzf_decompress(compressed.data(), + compressed.size(), + string_as_array(output), + output->size()); + if (destlen == 0) { + // This error probably means we had decided not to compress, + // and thus have stored input in output directly. + output->assign(compressed.data(), compressed.size()); + destlen = compressed.size(); + } + CHECK_EQ(destlen, size); + break; + } +#endif // LZF_VERSION + +#ifdef QLZ_VERSION_MAJOR + case QUICKLZ: { + output->resize(size); + qlz_state_decompress *state_decompress = new qlz_state_decompress; + int destlen = qlz_decompress(compressed.data(), + string_as_array(output), + state_decompress); + delete state_decompress; + CHECK_EQ(destlen, size); + break; + } +#endif // QLZ_VERSION_MAJOR + +#ifdef FASTLZ_VERSION + case FASTLZ: { + output->resize(size); + int destlen = fastlz_decompress(compressed.data(), + compressed.length(), + string_as_array(output), + size); + CHECK_EQ(destlen, size); + break; + } +#endif // FASTLZ_VERSION + + case SNAPPY: { + snappy::RawUncompress(compressed.data(), compressed.size(), + string_as_array(output)); + break; + } + + + default: { + return false; // the asked-for library wasn't compiled in + } + } + return true; +} + +static void Measure(const char* data, + size_t length, + CompressorType comp, + int repeats, + int block_size) { + // Run tests a few time and pick median running times + static const int kRuns = 5; + double ctime[kRuns]; + double utime[kRuns]; + int compressed_size = 0; + + { + // Chop the input into blocks + int num_blocks = (length + block_size - 1) / block_size; + vector<const char*> input(num_blocks); + vector<size_t> input_length(num_blocks); + vector<string> compressed(num_blocks); + vector<string> output(num_blocks); + for (int b = 0; b < num_blocks; b++) { + int input_start = b * block_size; + int input_limit = min<int>((b+1)*block_size, length); + input[b] = data+input_start; + input_length[b] = input_limit-input_start; + + // Pre-grow the output buffer so we don't measure string append time. + compressed[b].resize(MinimumRequiredOutputSpace(block_size, comp)); + } + + // First, try one trial compression to make sure the code is compiled in + if (!Compress(input[0], input_length[0], comp, &compressed[0], true)) { + LOG(WARNING) << "Skipping " << names[comp] << ": " + << "library not compiled in"; + return; + } + + for (int run = 0; run < kRuns; run++) { + CycleTimer ctimer, utimer; + + for (int b = 0; b < num_blocks; b++) { + // Pre-grow the output buffer so we don't measure string append time. + compressed[b].resize(MinimumRequiredOutputSpace(block_size, comp)); + } + + ctimer.Start(); + for (int b = 0; b < num_blocks; b++) + for (int i = 0; i < repeats; i++) + Compress(input[b], input_length[b], comp, &compressed[b], true); + ctimer.Stop(); + + // Compress once more, with resizing, so we don't leave junk + // at the end that will confuse the decompressor. + for (int b = 0; b < num_blocks; b++) { + Compress(input[b], input_length[b], comp, &compressed[b], false); + } + + for (int b = 0; b < num_blocks; b++) { + output[b].resize(input_length[b]); + } + + utimer.Start(); + for (int i = 0; i < repeats; i++) + for (int b = 0; b < num_blocks; b++) + Uncompress(compressed[b], comp, input_length[b], &output[b]); + utimer.Stop(); + + ctime[run] = ctimer.Get(); + utime[run] = utimer.Get(); + } + + compressed_size = 0; + for (int i = 0; i < compressed.size(); i++) { + compressed_size += compressed[i].size(); + } + } + + sort(ctime, ctime + kRuns); + sort(utime, utime + kRuns); + const int med = kRuns/2; + + float comp_rate = (length / ctime[med]) * repeats / 1048576.0; + float uncomp_rate = (length / utime[med]) * repeats / 1048576.0; + string x = names[comp]; + x += ":"; + string urate = (uncomp_rate >= 0) + ? StringPrintf("%.1f", uncomp_rate) + : string("?"); + printf("%-7s [b %dM] bytes %6d -> %6d %4.1f%% " + "comp %5.1f MB/s uncomp %5s MB/s\n", + x.c_str(), + block_size/(1<<20), + static_cast<int>(length), static_cast<uint32>(compressed_size), + (compressed_size * 100.0) / max<int>(1, length), + comp_rate, + urate.c_str()); +} + + +static int VerifyString(const string& input) { + string compressed; + DataEndingAtUnreadablePage i(input); + const size_t written = snappy::Compress(i.data(), i.size(), &compressed); + CHECK_EQ(written, compressed.size()); + CHECK_LE(compressed.size(), + snappy::MaxCompressedLength(input.size())); + CHECK(snappy::IsValidCompressedBuffer(compressed.data(), compressed.size())); + + string uncompressed; + DataEndingAtUnreadablePage c(compressed); + CHECK(snappy::Uncompress(c.data(), c.size(), &uncompressed)); + CHECK_EQ(uncompressed, input); + return uncompressed.size(); +} + + +// Test that data compressed by a compressor that does not +// obey block sizes is uncompressed properly. +static void VerifyNonBlockedCompression(const string& input) { + if (input.length() > snappy::kBlockSize) { + // We cannot test larger blocks than the maximum block size, obviously. + return; + } + + string prefix; + Varint::Append32(&prefix, input.size()); + + // Setup compression table + snappy::internal::WorkingMemory wmem; + int table_size; + uint16* table = wmem.GetHashTable(input.size(), &table_size); + + // Compress entire input in one shot + string compressed; + compressed += prefix; + compressed.resize(prefix.size()+snappy::MaxCompressedLength(input.size())); + char* dest = string_as_array(&compressed) + prefix.size(); + char* end = snappy::internal::CompressFragment(input.data(), input.size(), + dest, table, table_size); + compressed.resize(end - compressed.data()); + + // Uncompress into string + string uncomp_str; + CHECK(snappy::Uncompress(compressed.data(), compressed.size(), &uncomp_str)); + CHECK_EQ(uncomp_str, input); + +} + +// Expand the input so that it is at least K times as big as block size +static string Expand(const string& input) { + static const int K = 3; + string data = input; + while (data.size() < K * snappy::kBlockSize) { + data += input; + } + return data; +} + +static int Verify(const string& input) { + VLOG(1) << "Verifying input of size " << input.size(); + + // Compress using string based routines + const int result = VerifyString(input); + + + VerifyNonBlockedCompression(input); + if (!input.empty()) { + VerifyNonBlockedCompression(Expand(input)); + } + + + return result; +} + +// This test checks to ensure that snappy doesn't coredump if it gets +// corrupted data. + +static bool IsValidCompressedBuffer(const string& c) { + return snappy::IsValidCompressedBuffer(c.data(), c.size()); +} +static bool Uncompress(const string& c, string* u) { + return snappy::Uncompress(c.data(), c.size(), u); +} + +TYPED_TEST(CorruptedTest, VerifyCorrupted) { + string source = "making sure we don't crash with corrupted input"; + VLOG(1) << source; + string dest; + TypeParam uncmp; + snappy::Compress(source.data(), source.size(), &dest); + + // Mess around with the data. It's hard to simulate all possible + // corruptions; this is just one example ... + CHECK_GT(dest.size(), 3); + dest[1]--; + dest[3]++; + // this really ought to fail. + CHECK(!IsValidCompressedBuffer(TypeParam(dest))); + CHECK(!Uncompress(TypeParam(dest), &uncmp)); + + // This is testing for a security bug - a buffer that decompresses to 100k + // but we lie in the snappy header and only reserve 0 bytes of memory :) + source.resize(100000); + for (int i = 0; i < source.length(); ++i) { + source[i] = 'A'; + } + snappy::Compress(source.data(), source.size(), &dest); + dest[0] = dest[1] = dest[2] = dest[3] = 0; + CHECK(!IsValidCompressedBuffer(TypeParam(dest))); + CHECK(!Uncompress(TypeParam(dest), &uncmp)); + + if (sizeof(void *) == 4) { + // Another security check; check a crazy big length can't DoS us with an + // over-allocation. + // Currently this is done only for 32-bit builds. On 64-bit builds, + // where 3 GB might be an acceptable allocation size, Uncompress() + // attempts to decompress, and sometimes causes the test to run out of + // memory. + dest[0] = dest[1] = dest[2] = dest[3] = 0xff; + // This decodes to a really large size, i.e., about 3 GB. + dest[4] = 'k'; + CHECK(!IsValidCompressedBuffer(TypeParam(dest))); + CHECK(!Uncompress(TypeParam(dest), &uncmp)); + } else { + LOG(WARNING) << "Crazy decompression lengths not checked on 64-bit build"; + } + + // This decodes to about 2 MB; much smaller, but should still fail. + dest[0] = dest[1] = dest[2] = 0xff; + dest[3] = 0x00; + CHECK(!IsValidCompressedBuffer(TypeParam(dest))); + CHECK(!Uncompress(TypeParam(dest), &uncmp)); + + // try reading stuff in from a bad file. + for (int i = 1; i <= 3; ++i) { + string data = ReadTestDataFile(StringPrintf("baddata%d.snappy", i).c_str(), + 0); + string uncmp; + // check that we don't return a crazy length + size_t ulen; + CHECK(!snappy::GetUncompressedLength(data.data(), data.size(), &ulen) + || (ulen < (1<<20))); + uint32 ulen2; + snappy::ByteArraySource source(data.data(), data.size()); + CHECK(!snappy::GetUncompressedLength(&source, &ulen2) || + (ulen2 < (1<<20))); + CHECK(!IsValidCompressedBuffer(TypeParam(data))); + CHECK(!Uncompress(TypeParam(data), &uncmp)); + } +} + +// Helper routines to construct arbitrary compressed strings. +// These mirror the compression code in snappy.cc, but are copied +// here so that we can bypass some limitations in the how snappy.cc +// invokes these routines. +static void AppendLiteral(string* dst, const string& literal) { + if (literal.empty()) return; + int n = literal.size() - 1; + if (n < 60) { + // Fit length in tag byte + dst->push_back(0 | (n << 2)); + } else { + // Encode in upcoming bytes + char number[4]; + int count = 0; + while (n > 0) { + number[count++] = n & 0xff; + n >>= 8; + } + dst->push_back(0 | ((59+count) << 2)); + *dst += string(number, count); + } + *dst += literal; +} + +static void AppendCopy(string* dst, int offset, int length) { + while (length > 0) { + // Figure out how much to copy in one shot + int to_copy; + if (length >= 68) { + to_copy = 64; + } else if (length > 64) { + to_copy = 60; + } else { + to_copy = length; + } + length -= to_copy; + + if ((to_copy < 12) && (offset < 2048)) { + assert(to_copy-4 < 8); // Must fit in 3 bits + dst->push_back(1 | ((to_copy-4) << 2) | ((offset >> 8) << 5)); + dst->push_back(offset & 0xff); + } else if (offset < 65536) { + dst->push_back(2 | ((to_copy-1) << 2)); + dst->push_back(offset & 0xff); + dst->push_back(offset >> 8); + } else { + dst->push_back(3 | ((to_copy-1) << 2)); + dst->push_back(offset & 0xff); + dst->push_back((offset >> 8) & 0xff); + dst->push_back((offset >> 16) & 0xff); + dst->push_back((offset >> 24) & 0xff); + } + } +} + +TEST(Snappy, SimpleTests) { + Verify(""); + Verify("a"); + Verify("ab"); + Verify("abc"); + + Verify("aaaaaaa" + string(16, 'b') + string("aaaaa") + "abc"); + Verify("aaaaaaa" + string(256, 'b') + string("aaaaa") + "abc"); + Verify("aaaaaaa" + string(2047, 'b') + string("aaaaa") + "abc"); + Verify("aaaaaaa" + string(65536, 'b') + string("aaaaa") + "abc"); + Verify("abcaaaaaaa" + string(65536, 'b') + string("aaaaa") + "abc"); +} + +// Verify max blowup (lots of four-byte copies) +TEST(Snappy, MaxBlowup) { + string input; + for (int i = 0; i < 20000; i++) { + ACMRandom rnd(i); + uint32 bytes = static_cast<uint32>(rnd.Next()); + input.append(reinterpret_cast<char*>(&bytes), sizeof(bytes)); + } + for (int i = 19999; i >= 0; i--) { + ACMRandom rnd(i); + uint32 bytes = static_cast<uint32>(rnd.Next()); + input.append(reinterpret_cast<char*>(&bytes), sizeof(bytes)); + } + Verify(input); +} + +TEST(Snappy, RandomData) { + ACMRandom rnd(FLAGS_test_random_seed); + + const int num_ops = 20000; + for (int i = 0; i < num_ops; i++) { + if ((i % 1000) == 0) { + VLOG(0) << "Random op " << i << " of " << num_ops; + } + + string x; + int len = rnd.Uniform(4096); + if (i < 100) { + len = 65536 + rnd.Uniform(65536); + } + while (x.size() < len) { + int run_len = 1; + if (rnd.OneIn(10)) { + run_len = rnd.Skewed(8); + } + char c = (i < 100) ? rnd.Uniform(256) : rnd.Skewed(3); + while (run_len-- > 0 && x.size() < len) { + x += c; + } + } + + Verify(x); + } +} + +TEST(Snappy, FourByteOffset) { + // The new compressor cannot generate four-byte offsets since + // it chops up the input into 32KB pieces. So we hand-emit the + // copy manually. + + // The two fragments that make up the input string. + string fragment1 = "012345689abcdefghijklmnopqrstuvwxyz"; + string fragment2 = "some other string"; + + // How many times each fragment is emitted. + const int n1 = 2; + const int n2 = 100000 / fragment2.size(); + const int length = n1 * fragment1.size() + n2 * fragment2.size(); + + string compressed; + Varint::Append32(&compressed, length); + + AppendLiteral(&compressed, fragment1); + string src = fragment1; + for (int i = 0; i < n2; i++) { + AppendLiteral(&compressed, fragment2); + src += fragment2; + } + AppendCopy(&compressed, src.size(), fragment1.size()); + src += fragment1; + CHECK_EQ(length, src.size()); + + string uncompressed; + CHECK(snappy::IsValidCompressedBuffer(compressed.data(), compressed.size())); + CHECK(snappy::Uncompress(compressed.data(), compressed.size(), + &uncompressed)); + CHECK_EQ(uncompressed, src); +} + + +static bool CheckUncompressedLength(const string& compressed, + size_t* ulength) { + const bool result1 = snappy::GetUncompressedLength(compressed.data(), + compressed.size(), + ulength); + + snappy::ByteArraySource source(compressed.data(), compressed.size()); + uint32 length; + const bool result2 = snappy::GetUncompressedLength(&source, &length); + CHECK_EQ(result1, result2); + return result1; +} + +TEST(SnappyCorruption, TruncatedVarint) { + string compressed, uncompressed; + size_t ulength; + compressed.push_back('\xf0'); + CHECK(!CheckUncompressedLength(compressed, &ulength)); + CHECK(!snappy::IsValidCompressedBuffer(compressed.data(), compressed.size())); + CHECK(!snappy::Uncompress(compressed.data(), compressed.size(), + &uncompressed)); +} + +TEST(SnappyCorruption, UnterminatedVarint) { + string compressed, uncompressed; + size_t ulength; + compressed.push_back(128); + compressed.push_back(128); + compressed.push_back(128); + compressed.push_back(128); + compressed.push_back(128); + compressed.push_back(10); + CHECK(!CheckUncompressedLength(compressed, &ulength)); + CHECK(!snappy::IsValidCompressedBuffer(compressed.data(), compressed.size())); + CHECK(!snappy::Uncompress(compressed.data(), compressed.size(), + &uncompressed)); +} + +TEST(Snappy, ReadPastEndOfBuffer) { + // Check that we do not read past end of input + + // Make a compressed string that ends with a single-byte literal + string compressed; + Varint::Append32(&compressed, 1); + AppendLiteral(&compressed, "x"); + + string uncompressed; + DataEndingAtUnreadablePage c(compressed); + CHECK(snappy::Uncompress(c.data(), c.size(), &uncompressed)); + CHECK_EQ(uncompressed, string("x")); +} + +// Check for an infinite loop caused by a copy with offset==0 +TEST(Snappy, ZeroOffsetCopy) { + const char* compressed = "\x40\x12\x00\x00"; + // \x40 Length (must be > kMaxIncrementCopyOverflow) + // \x12\x00\x00 Copy with offset==0, length==5 + char uncompressed[100]; + EXPECT_FALSE(snappy::RawUncompress(compressed, 4, uncompressed)); +} + +TEST(Snappy, ZeroOffsetCopyValidation) { + const char* compressed = "\x05\x12\x00\x00"; + // \x05 Length + // \x12\x00\x00 Copy with offset==0, length==5 + EXPECT_FALSE(snappy::IsValidCompressedBuffer(compressed, 4)); +} + + +namespace { + +int TestFindMatchLength(const char* s1, const char *s2, unsigned length) { + return snappy::internal::FindMatchLength(s1, s2, s2 + length); +} + +} // namespace + +TEST(Snappy, FindMatchLength) { + // Exercise all different code paths through the function. + // 64-bit version: + + // Hit s1_limit in 64-bit loop, hit s1_limit in single-character loop. + EXPECT_EQ(6, TestFindMatchLength("012345", "012345", 6)); + EXPECT_EQ(11, TestFindMatchLength("01234567abc", "01234567abc", 11)); + + // Hit s1_limit in 64-bit loop, find a non-match in single-character loop. + EXPECT_EQ(9, TestFindMatchLength("01234567abc", "01234567axc", 9)); + + // Same, but edge cases. + EXPECT_EQ(11, TestFindMatchLength("01234567abc!", "01234567abc!", 11)); + EXPECT_EQ(11, TestFindMatchLength("01234567abc!", "01234567abc?", 11)); + + // Find non-match at once in first loop. + EXPECT_EQ(0, TestFindMatchLength("01234567xxxxxxxx", "?1234567xxxxxxxx", 16)); + EXPECT_EQ(1, TestFindMatchLength("01234567xxxxxxxx", "0?234567xxxxxxxx", 16)); + EXPECT_EQ(4, TestFindMatchLength("01234567xxxxxxxx", "01237654xxxxxxxx", 16)); + EXPECT_EQ(7, TestFindMatchLength("01234567xxxxxxxx", "0123456?xxxxxxxx", 16)); + + // Find non-match in first loop after one block. + EXPECT_EQ(8, TestFindMatchLength("abcdefgh01234567xxxxxxxx", + "abcdefgh?1234567xxxxxxxx", 24)); + EXPECT_EQ(9, TestFindMatchLength("abcdefgh01234567xxxxxxxx", + "abcdefgh0?234567xxxxxxxx", 24)); + EXPECT_EQ(12, TestFindMatchLength("abcdefgh01234567xxxxxxxx", + "abcdefgh01237654xxxxxxxx", 24)); + EXPECT_EQ(15, TestFindMatchLength("abcdefgh01234567xxxxxxxx", + "abcdefgh0123456?xxxxxxxx", 24)); + + // 32-bit version: + + // Short matches. + EXPECT_EQ(0, TestFindMatchLength("01234567", "?1234567", 8)); + EXPECT_EQ(1, TestFindMatchLength("01234567", "0?234567", 8)); + EXPECT_EQ(2, TestFindMatchLength("01234567", "01?34567", 8)); + EXPECT_EQ(3, TestFindMatchLength("01234567", "012?4567", 8)); + EXPECT_EQ(4, TestFindMatchLength("01234567", "0123?567", 8)); + EXPECT_EQ(5, TestFindMatchLength("01234567", "01234?67", 8)); + EXPECT_EQ(6, TestFindMatchLength("01234567", "012345?7", 8)); + EXPECT_EQ(7, TestFindMatchLength("01234567", "0123456?", 8)); + EXPECT_EQ(7, TestFindMatchLength("01234567", "0123456?", 7)); + EXPECT_EQ(7, TestFindMatchLength("01234567!", "0123456??", 7)); + + // Hit s1_limit in 32-bit loop, hit s1_limit in single-character loop. + EXPECT_EQ(10, TestFindMatchLength("xxxxxxabcd", "xxxxxxabcd", 10)); + EXPECT_EQ(10, TestFindMatchLength("xxxxxxabcd?", "xxxxxxabcd?", 10)); + EXPECT_EQ(13, TestFindMatchLength("xxxxxxabcdef", "xxxxxxabcdef", 13)); + + // Same, but edge cases. + EXPECT_EQ(12, TestFindMatchLength("xxxxxx0123abc!", "xxxxxx0123abc!", 12)); + EXPECT_EQ(12, TestFindMatchLength("xxxxxx0123abc!", "xxxxxx0123abc?", 12)); + + // Hit s1_limit in 32-bit loop, find a non-match in single-character loop. + EXPECT_EQ(11, TestFindMatchLength("xxxxxx0123abc", "xxxxxx0123axc", 13)); + + // Find non-match at once in first loop. + EXPECT_EQ(6, TestFindMatchLength("xxxxxx0123xxxxxxxx", + "xxxxxx?123xxxxxxxx", 18)); + EXPECT_EQ(7, TestFindMatchLength("xxxxxx0123xxxxxxxx", + "xxxxxx0?23xxxxxxxx", 18)); + EXPECT_EQ(8, TestFindMatchLength("xxxxxx0123xxxxxxxx", + "xxxxxx0132xxxxxxxx", 18)); + EXPECT_EQ(9, TestFindMatchLength("xxxxxx0123xxxxxxxx", + "xxxxxx012?xxxxxxxx", 18)); + + // Same, but edge cases. + EXPECT_EQ(6, TestFindMatchLength("xxxxxx0123", "xxxxxx?123", 10)); + EXPECT_EQ(7, TestFindMatchLength("xxxxxx0123", "xxxxxx0?23", 10)); + EXPECT_EQ(8, TestFindMatchLength("xxxxxx0123", "xxxxxx0132", 10)); + EXPECT_EQ(9, TestFindMatchLength("xxxxxx0123", "xxxxxx012?", 10)); + + // Find non-match in first loop after one block. + EXPECT_EQ(10, TestFindMatchLength("xxxxxxabcd0123xx", + "xxxxxxabcd?123xx", 16)); + EXPECT_EQ(11, TestFindMatchLength("xxxxxxabcd0123xx", + "xxxxxxabcd0?23xx", 16)); + EXPECT_EQ(12, TestFindMatchLength("xxxxxxabcd0123xx", + "xxxxxxabcd0132xx", 16)); + EXPECT_EQ(13, TestFindMatchLength("xxxxxxabcd0123xx", + "xxxxxxabcd012?xx", 16)); + + // Same, but edge cases. + EXPECT_EQ(10, TestFindMatchLength("xxxxxxabcd0123", "xxxxxxabcd?123", 14)); + EXPECT_EQ(11, TestFindMatchLength("xxxxxxabcd0123", "xxxxxxabcd0?23", 14)); + EXPECT_EQ(12, TestFindMatchLength("xxxxxxabcd0123", "xxxxxxabcd0132", 14)); + EXPECT_EQ(13, TestFindMatchLength("xxxxxxabcd0123", "xxxxxxabcd012?", 14)); +} + +TEST(Snappy, FindMatchLengthRandom) { + const int kNumTrials = 10000; + const int kTypicalLength = 10; + ACMRandom rnd(FLAGS_test_random_seed); + + for (int i = 0; i < kNumTrials; i++) { + string s, t; + char a = rnd.Rand8(); + char b = rnd.Rand8(); + while (!rnd.OneIn(kTypicalLength)) { + s.push_back(rnd.OneIn(2) ? a : b); + t.push_back(rnd.OneIn(2) ? a : b); + } + DataEndingAtUnreadablePage u(s); + DataEndingAtUnreadablePage v(t); + int matched = snappy::internal::FindMatchLength( + u.data(), v.data(), v.data() + t.size()); + if (matched == t.size()) { + EXPECT_EQ(s, t); + } else { + EXPECT_NE(s[matched], t[matched]); + for (int j = 0; j < matched; j++) { + EXPECT_EQ(s[j], t[j]); + } + } + } +} + + +static void CompressFile(const char* fname) { + string fullinput; + file::GetContents(fname, &fullinput, file::Defaults()).CheckSuccess(); + + string compressed; + Compress(fullinput.data(), fullinput.size(), SNAPPY, &compressed, false); + + file::SetContents(string(fname).append(".comp"), compressed, file::Defaults()) + .CheckSuccess(); +} + +static void UncompressFile(const char* fname) { + string fullinput; + file::GetContents(fname, &fullinput, file::Defaults()).CheckSuccess(); + + size_t uncompLength; + CHECK(CheckUncompressedLength(fullinput, &uncompLength)); + + string uncompressed; + uncompressed.resize(uncompLength); + CHECK(snappy::Uncompress(fullinput.data(), fullinput.size(), &uncompressed)); + + file::SetContents(string(fname).append(".uncomp"), uncompressed, + file::Defaults()).CheckSuccess(); +} + +static void MeasureFile(const char* fname) { + string fullinput; + file::GetContents(fname, &fullinput, file::Defaults()).CheckSuccess(); + printf("%-40s :\n", fname); + + int start_len = (FLAGS_start_len < 0) ? fullinput.size() : FLAGS_start_len; + int end_len = fullinput.size(); + if (FLAGS_end_len >= 0) { + end_len = min<int>(fullinput.size(), FLAGS_end_len); + } + for (int len = start_len; len <= end_len; len++) { + const char* const input = fullinput.data(); + int repeats = (FLAGS_bytes + len) / (len + 1); + if (FLAGS_zlib) Measure(input, len, ZLIB, repeats, 1024<<10); + if (FLAGS_lzo) Measure(input, len, LZO, repeats, 1024<<10); + if (FLAGS_liblzf) Measure(input, len, LIBLZF, repeats, 1024<<10); + if (FLAGS_quicklz) Measure(input, len, QUICKLZ, repeats, 1024<<10); + if (FLAGS_fastlz) Measure(input, len, FASTLZ, repeats, 1024<<10); + if (FLAGS_snappy) Measure(input, len, SNAPPY, repeats, 4096<<10); + + // For block-size based measurements + if (0 && FLAGS_snappy) { + Measure(input, len, SNAPPY, repeats, 8<<10); + Measure(input, len, SNAPPY, repeats, 16<<10); + Measure(input, len, SNAPPY, repeats, 32<<10); + Measure(input, len, SNAPPY, repeats, 64<<10); + Measure(input, len, SNAPPY, repeats, 256<<10); + Measure(input, len, SNAPPY, repeats, 1024<<10); + } + } +} + +static struct { + const char* label; + const char* filename; + size_t size_limit; +} files[] = { + { "html", "html", 0 }, + { "urls", "urls.10K", 0 }, + { "jpg", "house.jpg", 0 }, + { "jpg_200", "house.jpg", 200 }, + { "pdf", "mapreduce-osdi-1.pdf", 0 }, + { "html4", "html_x_4", 0 }, + { "cp", "cp.html", 0 }, + { "c", "fields.c", 0 }, + { "lsp", "grammar.lsp", 0 }, + { "xls", "kennedy.xls", 0 }, + { "xls_200", "kennedy.xls", 200 }, + { "txt1", "alice29.txt", 0 }, + { "txt2", "asyoulik.txt", 0 }, + { "txt3", "lcet10.txt", 0 }, + { "txt4", "plrabn12.txt", 0 }, + { "bin", "ptt5", 0 }, + { "bin_200", "ptt5", 200 }, + { "sum", "sum", 0 }, + { "man", "xargs.1", 0 }, + { "pb", "geo.protodata", 0 }, + { "gaviota", "kppkn.gtb", 0 }, +}; + +static void BM_UFlat(int iters, int arg) { + StopBenchmarkTiming(); + + // Pick file to process based on "arg" + CHECK_GE(arg, 0); + CHECK_LT(arg, ARRAYSIZE(files)); + string contents = ReadTestDataFile(files[arg].filename, + files[arg].size_limit); + + string zcontents; + snappy::Compress(contents.data(), contents.size(), &zcontents); + char* dst = new char[contents.size()]; + + SetBenchmarkBytesProcessed(static_cast<int64>(iters) * + static_cast<int64>(contents.size())); + SetBenchmarkLabel(files[arg].label); + StartBenchmarkTiming(); + while (iters-- > 0) { + CHECK(snappy::RawUncompress(zcontents.data(), zcontents.size(), dst)); + } + StopBenchmarkTiming(); + + delete[] dst; +} +BENCHMARK(BM_UFlat)->DenseRange(0, ARRAYSIZE(files) - 1); + +static void BM_UValidate(int iters, int arg) { + StopBenchmarkTiming(); + + // Pick file to process based on "arg" + CHECK_GE(arg, 0); + CHECK_LT(arg, ARRAYSIZE(files)); + string contents = ReadTestDataFile(files[arg].filename, + files[arg].size_limit); + + string zcontents; + snappy::Compress(contents.data(), contents.size(), &zcontents); + + SetBenchmarkBytesProcessed(static_cast<int64>(iters) * + static_cast<int64>(contents.size())); + SetBenchmarkLabel(files[arg].label); + StartBenchmarkTiming(); + while (iters-- > 0) { + CHECK(snappy::IsValidCompressedBuffer(zcontents.data(), zcontents.size())); + } + StopBenchmarkTiming(); +} +BENCHMARK(BM_UValidate)->DenseRange(0, 4); + + +static void BM_ZFlat(int iters, int arg) { + StopBenchmarkTiming(); + + // Pick file to process based on "arg" + CHECK_GE(arg, 0); + CHECK_LT(arg, ARRAYSIZE(files)); + string contents = ReadTestDataFile(files[arg].filename, + files[arg].size_limit); + + char* dst = new char[snappy::MaxCompressedLength(contents.size())]; + + SetBenchmarkBytesProcessed(static_cast<int64>(iters) * + static_cast<int64>(contents.size())); + StartBenchmarkTiming(); + + size_t zsize = 0; + while (iters-- > 0) { + snappy::RawCompress(contents.data(), contents.size(), dst, &zsize); + } + StopBenchmarkTiming(); + const double compression_ratio = + static_cast<double>(zsize) / std::max<size_t>(1, contents.size()); + SetBenchmarkLabel(StringPrintf("%s (%.2f %%)", + files[arg].label, 100.0 * compression_ratio)); + VLOG(0) << StringPrintf("compression for %s: %zd -> %zd bytes", + files[arg].label, contents.size(), zsize); + delete[] dst; +} +BENCHMARK(BM_ZFlat)->DenseRange(0, ARRAYSIZE(files) - 1); + + +} // namespace snappy + + +int main(int argc, char** argv) { + InitGoogle(argv[0], &argc, &argv, true); + File::Init(); + RunSpecifiedBenchmarks(); + + + if (argc >= 2) { + for (int arg = 1; arg < argc; arg++) { + if (FLAGS_write_compressed) { + CompressFile(argv[arg]); + } else if (FLAGS_write_uncompressed) { + UncompressFile(argv[arg]); + } else { + MeasureFile(argv[arg]); + } + } + return 0; + } + + return RUN_ALL_TESTS(); +} |