1354 lines
39 KiB
Go
1354 lines
39 KiB
Go
// Copyright 2011 The Snappy-Go Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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package snappy
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import (
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"bytes"
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"encoding/binary"
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"flag"
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"fmt"
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"io"
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"io/ioutil"
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"math/rand"
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"net/http"
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"os"
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"os/exec"
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"path/filepath"
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"runtime"
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"strings"
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"testing"
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)
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var (
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download = flag.Bool("download", false, "If true, download any missing files before running benchmarks")
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testdataDir = flag.String("testdataDir", "testdata", "Directory containing the test data")
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benchdataDir = flag.String("benchdataDir", "testdata/bench", "Directory containing the benchmark data")
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)
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// goEncoderShouldMatchCppEncoder is whether to test that the algorithm used by
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// Go's encoder matches byte-for-byte what the C++ snappy encoder produces, on
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// this GOARCH. There is more than one valid encoding of any given input, and
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// there is more than one good algorithm along the frontier of trading off
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// throughput for output size. Nonetheless, we presume that the C++ encoder's
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// algorithm is a good one and has been tested on a wide range of inputs, so
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// matching that exactly should mean that the Go encoder's algorithm is also
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// good, without needing to gather our own corpus of test data.
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//
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// The exact algorithm used by the C++ code is potentially endian dependent, as
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// it puns a byte pointer to a uint32 pointer to load, hash and compare 4 bytes
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// at a time. The Go implementation is endian agnostic, in that its output is
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// the same (as little-endian C++ code), regardless of the CPU's endianness.
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//
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// Thus, when comparing Go's output to C++ output generated beforehand, such as
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// the "testdata/pi.txt.rawsnappy" file generated by C++ code on a little-
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// endian system, we can run that test regardless of the runtime.GOARCH value.
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//
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// When comparing Go's output to dynamically generated C++ output, i.e. the
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// result of fork/exec'ing a C++ program, we can run that test only on
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// little-endian systems, because the C++ output might be different on
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// big-endian systems. The runtime package doesn't export endianness per se,
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// but we can restrict this match-C++ test to common little-endian systems.
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const goEncoderShouldMatchCppEncoder = runtime.GOARCH == "386" || runtime.GOARCH == "amd64" || runtime.GOARCH == "arm"
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func TestMaxEncodedLenOfMaxBlockSize(t *testing.T) {
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got := maxEncodedLenOfMaxBlockSize
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want := MaxEncodedLen(maxBlockSize)
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if got != want {
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t.Fatalf("got %d, want %d", got, want)
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}
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}
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func cmp(a, b []byte) error {
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if bytes.Equal(a, b) {
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return nil
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}
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if len(a) != len(b) {
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return fmt.Errorf("got %d bytes, want %d", len(a), len(b))
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}
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for i := range a {
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if a[i] != b[i] {
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return fmt.Errorf("byte #%d: got 0x%02x, want 0x%02x", i, a[i], b[i])
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}
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}
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return nil
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}
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func roundtrip(b, ebuf, dbuf []byte) error {
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d, err := Decode(dbuf, Encode(ebuf, b))
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if err != nil {
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return fmt.Errorf("decoding error: %v", err)
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}
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if err := cmp(d, b); err != nil {
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return fmt.Errorf("roundtrip mismatch: %v", err)
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}
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return nil
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}
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func TestEmpty(t *testing.T) {
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if err := roundtrip(nil, nil, nil); err != nil {
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t.Fatal(err)
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}
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}
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func TestSmallCopy(t *testing.T) {
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for _, ebuf := range [][]byte{nil, make([]byte, 20), make([]byte, 64)} {
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for _, dbuf := range [][]byte{nil, make([]byte, 20), make([]byte, 64)} {
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for i := 0; i < 32; i++ {
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s := "aaaa" + strings.Repeat("b", i) + "aaaabbbb"
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if err := roundtrip([]byte(s), ebuf, dbuf); err != nil {
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t.Errorf("len(ebuf)=%d, len(dbuf)=%d, i=%d: %v", len(ebuf), len(dbuf), i, err)
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}
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}
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}
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}
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}
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func TestSmallRand(t *testing.T) {
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rng := rand.New(rand.NewSource(1))
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for n := 1; n < 20000; n += 23 {
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b := make([]byte, n)
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for i := range b {
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b[i] = uint8(rng.Intn(256))
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}
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if err := roundtrip(b, nil, nil); err != nil {
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t.Fatal(err)
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}
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}
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}
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func TestSmallRegular(t *testing.T) {
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for n := 1; n < 20000; n += 23 {
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b := make([]byte, n)
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for i := range b {
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b[i] = uint8(i%10 + 'a')
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}
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if err := roundtrip(b, nil, nil); err != nil {
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t.Fatal(err)
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}
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}
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}
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func TestInvalidVarint(t *testing.T) {
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testCases := []struct {
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desc string
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input string
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}{{
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"invalid varint, final byte has continuation bit set",
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"\xff",
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}, {
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"invalid varint, value overflows uint64",
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"\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\x00",
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}, {
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// https://github.com/google/snappy/blob/master/format_description.txt
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// says that "the stream starts with the uncompressed length [as a
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// varint] (up to a maximum of 2^32 - 1)".
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"valid varint (as uint64), but value overflows uint32",
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"\x80\x80\x80\x80\x10",
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}}
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for _, tc := range testCases {
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input := []byte(tc.input)
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if _, err := DecodedLen(input); err != ErrCorrupt {
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t.Errorf("%s: DecodedLen: got %v, want ErrCorrupt", tc.desc, err)
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}
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if _, err := Decode(nil, input); err != ErrCorrupt {
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t.Errorf("%s: Decode: got %v, want ErrCorrupt", tc.desc, err)
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}
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}
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}
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func TestDecode(t *testing.T) {
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lit40Bytes := make([]byte, 40)
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for i := range lit40Bytes {
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lit40Bytes[i] = byte(i)
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}
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lit40 := string(lit40Bytes)
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testCases := []struct {
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desc string
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input string
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want string
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wantErr error
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}{{
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`decodedLen=0; valid input`,
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"\x00",
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"",
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nil,
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}, {
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`decodedLen=3; tagLiteral, 0-byte length; length=3; valid input`,
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"\x03" + "\x08\xff\xff\xff",
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"\xff\xff\xff",
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nil,
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}, {
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`decodedLen=2; tagLiteral, 0-byte length; length=3; not enough dst bytes`,
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"\x02" + "\x08\xff\xff\xff",
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"",
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ErrCorrupt,
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}, {
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`decodedLen=3; tagLiteral, 0-byte length; length=3; not enough src bytes`,
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"\x03" + "\x08\xff\xff",
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"",
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ErrCorrupt,
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}, {
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`decodedLen=40; tagLiteral, 0-byte length; length=40; valid input`,
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"\x28" + "\x9c" + lit40,
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lit40,
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nil,
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}, {
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`decodedLen=1; tagLiteral, 1-byte length; not enough length bytes`,
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"\x01" + "\xf0",
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"",
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ErrCorrupt,
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}, {
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`decodedLen=3; tagLiteral, 1-byte length; length=3; valid input`,
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"\x03" + "\xf0\x02\xff\xff\xff",
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"\xff\xff\xff",
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nil,
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}, {
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`decodedLen=1; tagLiteral, 2-byte length; not enough length bytes`,
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"\x01" + "\xf4\x00",
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"",
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ErrCorrupt,
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}, {
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`decodedLen=3; tagLiteral, 2-byte length; length=3; valid input`,
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"\x03" + "\xf4\x02\x00\xff\xff\xff",
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"\xff\xff\xff",
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nil,
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}, {
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`decodedLen=1; tagLiteral, 3-byte length; not enough length bytes`,
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"\x01" + "\xf8\x00\x00",
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"",
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ErrCorrupt,
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}, {
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`decodedLen=3; tagLiteral, 3-byte length; length=3; valid input`,
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"\x03" + "\xf8\x02\x00\x00\xff\xff\xff",
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"\xff\xff\xff",
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nil,
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}, {
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`decodedLen=1; tagLiteral, 4-byte length; not enough length bytes`,
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"\x01" + "\xfc\x00\x00\x00",
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"",
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ErrCorrupt,
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}, {
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`decodedLen=1; tagLiteral, 4-byte length; length=3; not enough dst bytes`,
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"\x01" + "\xfc\x02\x00\x00\x00\xff\xff\xff",
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"",
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ErrCorrupt,
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}, {
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`decodedLen=4; tagLiteral, 4-byte length; length=3; not enough src bytes`,
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"\x04" + "\xfc\x02\x00\x00\x00\xff",
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"",
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ErrCorrupt,
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}, {
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`decodedLen=3; tagLiteral, 4-byte length; length=3; valid input`,
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"\x03" + "\xfc\x02\x00\x00\x00\xff\xff\xff",
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"\xff\xff\xff",
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nil,
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}, {
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`decodedLen=4; tagCopy1, 1 extra length|offset byte; not enough extra bytes`,
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"\x04" + "\x01",
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"",
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ErrCorrupt,
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}, {
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`decodedLen=4; tagCopy2, 2 extra length|offset bytes; not enough extra bytes`,
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"\x04" + "\x02\x00",
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"",
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ErrCorrupt,
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}, {
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`decodedLen=4; tagCopy4, 4 extra length|offset bytes; not enough extra bytes`,
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"\x04" + "\x03\x00\x00\x00",
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"",
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ErrCorrupt,
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}, {
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`decodedLen=4; tagLiteral (4 bytes "abcd"); valid input`,
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"\x04" + "\x0cabcd",
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"abcd",
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nil,
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}, {
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`decodedLen=13; tagLiteral (4 bytes "abcd"); tagCopy1; length=9 offset=4; valid input`,
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"\x0d" + "\x0cabcd" + "\x15\x04",
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"abcdabcdabcda",
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nil,
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}, {
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`decodedLen=8; tagLiteral (4 bytes "abcd"); tagCopy1; length=4 offset=4; valid input`,
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"\x08" + "\x0cabcd" + "\x01\x04",
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"abcdabcd",
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nil,
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}, {
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`decodedLen=8; tagLiteral (4 bytes "abcd"); tagCopy1; length=4 offset=2; valid input`,
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"\x08" + "\x0cabcd" + "\x01\x02",
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"abcdcdcd",
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nil,
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}, {
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`decodedLen=8; tagLiteral (4 bytes "abcd"); tagCopy1; length=4 offset=1; valid input`,
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"\x08" + "\x0cabcd" + "\x01\x01",
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"abcddddd",
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nil,
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}, {
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`decodedLen=8; tagLiteral (4 bytes "abcd"); tagCopy1; length=4 offset=0; zero offset`,
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"\x08" + "\x0cabcd" + "\x01\x00",
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"",
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ErrCorrupt,
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}, {
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`decodedLen=9; tagLiteral (4 bytes "abcd"); tagCopy1; length=4 offset=4; inconsistent dLen`,
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"\x09" + "\x0cabcd" + "\x01\x04",
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"",
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ErrCorrupt,
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}, {
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`decodedLen=8; tagLiteral (4 bytes "abcd"); tagCopy1; length=4 offset=5; offset too large`,
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"\x08" + "\x0cabcd" + "\x01\x05",
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"",
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ErrCorrupt,
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}, {
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`decodedLen=7; tagLiteral (4 bytes "abcd"); tagCopy1; length=4 offset=4; length too large`,
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"\x07" + "\x0cabcd" + "\x01\x04",
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"",
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ErrCorrupt,
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}, {
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`decodedLen=6; tagLiteral (4 bytes "abcd"); tagCopy2; length=2 offset=3; valid input`,
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"\x06" + "\x0cabcd" + "\x06\x03\x00",
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"abcdbc",
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nil,
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}, {
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`decodedLen=6; tagLiteral (4 bytes "abcd"); tagCopy4; length=2 offset=3; valid input`,
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"\x06" + "\x0cabcd" + "\x07\x03\x00\x00\x00",
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"abcdbc",
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nil,
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}}
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const (
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// notPresentXxx defines a range of byte values [0xa0, 0xc5) that are
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// not present in either the input or the output. It is written to dBuf
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// to check that Decode does not write bytes past the end of
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// dBuf[:dLen].
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//
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// The magic number 37 was chosen because it is prime. A more 'natural'
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// number like 32 might lead to a false negative if, for example, a
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// byte was incorrectly copied 4*8 bytes later.
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notPresentBase = 0xa0
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notPresentLen = 37
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)
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var dBuf [100]byte
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loop:
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for i, tc := range testCases {
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input := []byte(tc.input)
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for _, x := range input {
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if notPresentBase <= x && x < notPresentBase+notPresentLen {
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t.Errorf("#%d (%s): input shouldn't contain %#02x\ninput: % x", i, tc.desc, x, input)
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continue loop
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}
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}
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dLen, n := binary.Uvarint(input)
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if n <= 0 {
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t.Errorf("#%d (%s): invalid varint-encoded dLen", i, tc.desc)
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continue
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}
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if dLen > uint64(len(dBuf)) {
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t.Errorf("#%d (%s): dLen %d is too large", i, tc.desc, dLen)
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continue
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}
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for j := range dBuf {
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dBuf[j] = byte(notPresentBase + j%notPresentLen)
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}
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g, gotErr := Decode(dBuf[:], input)
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if got := string(g); got != tc.want || gotErr != tc.wantErr {
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t.Errorf("#%d (%s):\ngot %q, %v\nwant %q, %v",
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i, tc.desc, got, gotErr, tc.want, tc.wantErr)
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continue
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}
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for j, x := range dBuf {
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if uint64(j) < dLen {
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continue
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}
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if w := byte(notPresentBase + j%notPresentLen); x != w {
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t.Errorf("#%d (%s): Decode overrun: dBuf[%d] was modified: got %#02x, want %#02x\ndBuf: % x",
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i, tc.desc, j, x, w, dBuf)
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continue loop
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}
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}
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}
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}
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func TestDecodeCopy4(t *testing.T) {
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dots := strings.Repeat(".", 65536)
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input := strings.Join([]string{
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"\x89\x80\x04", // decodedLen = 65545.
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"\x0cpqrs", // 4-byte literal "pqrs".
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"\xf4\xff\xff" + dots, // 65536-byte literal dots.
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"\x13\x04\x00\x01\x00", // tagCopy4; length=5 offset=65540.
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}, "")
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gotBytes, err := Decode(nil, []byte(input))
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if err != nil {
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t.Fatal(err)
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}
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got := string(gotBytes)
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want := "pqrs" + dots + "pqrs."
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if len(got) != len(want) {
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t.Fatalf("got %d bytes, want %d", len(got), len(want))
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}
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if got != want {
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for i := 0; i < len(got); i++ {
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if g, w := got[i], want[i]; g != w {
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t.Fatalf("byte #%d: got %#02x, want %#02x", i, g, w)
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}
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}
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}
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}
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|
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// TestDecodeLengthOffset tests decoding an encoding of the form literal +
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// copy-length-offset + literal. For example: "abcdefghijkl" + "efghij" + "AB".
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func TestDecodeLengthOffset(t *testing.T) {
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const (
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prefix = "abcdefghijklmnopqr"
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suffix = "ABCDEFGHIJKLMNOPQR"
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|
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// notPresentXxx defines a range of byte values [0xa0, 0xc5) that are
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// not present in either the input or the output. It is written to
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// gotBuf to check that Decode does not write bytes past the end of
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// gotBuf[:totalLen].
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//
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// The magic number 37 was chosen because it is prime. A more 'natural'
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// number like 32 might lead to a false negative if, for example, a
|
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// byte was incorrectly copied 4*8 bytes later.
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notPresentBase = 0xa0
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notPresentLen = 37
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)
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var gotBuf, wantBuf, inputBuf [128]byte
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for length := 1; length <= 18; length++ {
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for offset := 1; offset <= 18; offset++ {
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loop:
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for suffixLen := 0; suffixLen <= 18; suffixLen++ {
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totalLen := len(prefix) + length + suffixLen
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inputLen := binary.PutUvarint(inputBuf[:], uint64(totalLen))
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inputBuf[inputLen] = tagLiteral + 4*byte(len(prefix)-1)
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inputLen++
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inputLen += copy(inputBuf[inputLen:], prefix)
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inputBuf[inputLen+0] = tagCopy2 + 4*byte(length-1)
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inputBuf[inputLen+1] = byte(offset)
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inputBuf[inputLen+2] = 0x00
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inputLen += 3
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if suffixLen > 0 {
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inputBuf[inputLen] = tagLiteral + 4*byte(suffixLen-1)
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inputLen++
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inputLen += copy(inputBuf[inputLen:], suffix[:suffixLen])
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}
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input := inputBuf[:inputLen]
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for i := range gotBuf {
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gotBuf[i] = byte(notPresentBase + i%notPresentLen)
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}
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got, err := Decode(gotBuf[:], input)
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if err != nil {
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t.Errorf("length=%d, offset=%d; suffixLen=%d: %v", length, offset, suffixLen, err)
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continue
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}
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wantLen := 0
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wantLen += copy(wantBuf[wantLen:], prefix)
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for i := 0; i < length; i++ {
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wantBuf[wantLen] = wantBuf[wantLen-offset]
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wantLen++
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}
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wantLen += copy(wantBuf[wantLen:], suffix[:suffixLen])
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want := wantBuf[:wantLen]
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for _, x := range input {
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if notPresentBase <= x && x < notPresentBase+notPresentLen {
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t.Errorf("length=%d, offset=%d; suffixLen=%d: input shouldn't contain %#02x\ninput: % x",
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length, offset, suffixLen, x, input)
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continue loop
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}
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}
|
|
for i, x := range gotBuf {
|
|
if i < totalLen {
|
|
continue
|
|
}
|
|
if w := byte(notPresentBase + i%notPresentLen); x != w {
|
|
t.Errorf("length=%d, offset=%d; suffixLen=%d; totalLen=%d: "+
|
|
"Decode overrun: gotBuf[%d] was modified: got %#02x, want %#02x\ngotBuf: % x",
|
|
length, offset, suffixLen, totalLen, i, x, w, gotBuf)
|
|
continue loop
|
|
}
|
|
}
|
|
for _, x := range want {
|
|
if notPresentBase <= x && x < notPresentBase+notPresentLen {
|
|
t.Errorf("length=%d, offset=%d; suffixLen=%d: want shouldn't contain %#02x\nwant: % x",
|
|
length, offset, suffixLen, x, want)
|
|
continue loop
|
|
}
|
|
}
|
|
|
|
if !bytes.Equal(got, want) {
|
|
t.Errorf("length=%d, offset=%d; suffixLen=%d:\ninput % x\ngot % x\nwant % x",
|
|
length, offset, suffixLen, input, got, want)
|
|
continue
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
const (
|
|
goldenText = "Mark.Twain-Tom.Sawyer.txt"
|
|
goldenCompressed = goldenText + ".rawsnappy"
|
|
)
|
|
|
|
func TestDecodeGoldenInput(t *testing.T) {
|
|
tDir := filepath.FromSlash(*testdataDir)
|
|
src, err := ioutil.ReadFile(filepath.Join(tDir, goldenCompressed))
|
|
if err != nil {
|
|
t.Fatalf("ReadFile: %v", err)
|
|
}
|
|
got, err := Decode(nil, src)
|
|
if err != nil {
|
|
t.Fatalf("Decode: %v", err)
|
|
}
|
|
want, err := ioutil.ReadFile(filepath.Join(tDir, goldenText))
|
|
if err != nil {
|
|
t.Fatalf("ReadFile: %v", err)
|
|
}
|
|
if err := cmp(got, want); err != nil {
|
|
t.Fatal(err)
|
|
}
|
|
}
|
|
|
|
func TestEncodeGoldenInput(t *testing.T) {
|
|
tDir := filepath.FromSlash(*testdataDir)
|
|
src, err := ioutil.ReadFile(filepath.Join(tDir, goldenText))
|
|
if err != nil {
|
|
t.Fatalf("ReadFile: %v", err)
|
|
}
|
|
got := Encode(nil, src)
|
|
want, err := ioutil.ReadFile(filepath.Join(tDir, goldenCompressed))
|
|
if err != nil {
|
|
t.Fatalf("ReadFile: %v", err)
|
|
}
|
|
if err := cmp(got, want); err != nil {
|
|
t.Fatal(err)
|
|
}
|
|
}
|
|
|
|
func TestExtendMatchGoldenInput(t *testing.T) {
|
|
tDir := filepath.FromSlash(*testdataDir)
|
|
src, err := ioutil.ReadFile(filepath.Join(tDir, goldenText))
|
|
if err != nil {
|
|
t.Fatalf("ReadFile: %v", err)
|
|
}
|
|
for i, tc := range extendMatchGoldenTestCases {
|
|
got := extendMatch(src, tc.i, tc.j)
|
|
if got != tc.want {
|
|
t.Errorf("test #%d: i, j = %5d, %5d: got %5d (= j + %6d), want %5d (= j + %6d)",
|
|
i, tc.i, tc.j, got, got-tc.j, tc.want, tc.want-tc.j)
|
|
}
|
|
}
|
|
}
|
|
|
|
func TestExtendMatch(t *testing.T) {
|
|
// ref is a simple, reference implementation of extendMatch.
|
|
ref := func(src []byte, i, j int) int {
|
|
for ; j < len(src) && src[i] == src[j]; i, j = i+1, j+1 {
|
|
}
|
|
return j
|
|
}
|
|
|
|
nums := []int{0, 1, 2, 7, 8, 9, 29, 30, 31, 32, 33, 34, 38, 39, 40}
|
|
for yIndex := 40; yIndex > 30; yIndex-- {
|
|
xxx := bytes.Repeat([]byte("x"), 40)
|
|
if yIndex < len(xxx) {
|
|
xxx[yIndex] = 'y'
|
|
}
|
|
for _, i := range nums {
|
|
for _, j := range nums {
|
|
if i >= j {
|
|
continue
|
|
}
|
|
got := extendMatch(xxx, i, j)
|
|
want := ref(xxx, i, j)
|
|
if got != want {
|
|
t.Errorf("yIndex=%d, i=%d, j=%d: got %d, want %d", yIndex, i, j, got, want)
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
const snappytoolCmdName = "cmd/snappytool/snappytool"
|
|
|
|
func skipTestSameEncodingAsCpp() (msg string) {
|
|
if !goEncoderShouldMatchCppEncoder {
|
|
return fmt.Sprintf("skipping testing that the encoding is byte-for-byte identical to C++: GOARCH=%s", runtime.GOARCH)
|
|
}
|
|
if _, err := os.Stat(snappytoolCmdName); err != nil {
|
|
return fmt.Sprintf("could not find snappytool: %v", err)
|
|
}
|
|
return ""
|
|
}
|
|
|
|
func runTestSameEncodingAsCpp(src []byte) error {
|
|
got := Encode(nil, src)
|
|
|
|
cmd := exec.Command(snappytoolCmdName, "-e")
|
|
cmd.Stdin = bytes.NewReader(src)
|
|
want, err := cmd.Output()
|
|
if err != nil {
|
|
return fmt.Errorf("could not run snappytool: %v", err)
|
|
}
|
|
return cmp(got, want)
|
|
}
|
|
|
|
func TestSameEncodingAsCppShortCopies(t *testing.T) {
|
|
if msg := skipTestSameEncodingAsCpp(); msg != "" {
|
|
t.Skip(msg)
|
|
}
|
|
src := bytes.Repeat([]byte{'a'}, 20)
|
|
for i := 0; i <= len(src); i++ {
|
|
if err := runTestSameEncodingAsCpp(src[:i]); err != nil {
|
|
t.Errorf("i=%d: %v", i, err)
|
|
}
|
|
}
|
|
}
|
|
|
|
func TestSameEncodingAsCppLongFiles(t *testing.T) {
|
|
if msg := skipTestSameEncodingAsCpp(); msg != "" {
|
|
t.Skip(msg)
|
|
}
|
|
bDir := filepath.FromSlash(*benchdataDir)
|
|
failed := false
|
|
for i, tf := range testFiles {
|
|
if err := downloadBenchmarkFiles(t, tf.filename); err != nil {
|
|
t.Fatalf("failed to download testdata: %s", err)
|
|
}
|
|
data := readFile(t, filepath.Join(bDir, tf.filename))
|
|
if n := tf.sizeLimit; 0 < n && n < len(data) {
|
|
data = data[:n]
|
|
}
|
|
if err := runTestSameEncodingAsCpp(data); err != nil {
|
|
t.Errorf("i=%d: %v", i, err)
|
|
failed = true
|
|
}
|
|
}
|
|
if failed {
|
|
t.Errorf("was the snappytool program built against the C++ snappy library version " +
|
|
"d53de187 or later, commited on 2016-04-05? See " +
|
|
"https://github.com/google/snappy/commit/d53de18799418e113e44444252a39b12a0e4e0cc")
|
|
}
|
|
}
|
|
|
|
// TestSlowForwardCopyOverrun tests the "expand the pattern" algorithm
|
|
// described in decode_amd64.s and its claim of a 10 byte overrun worst case.
|
|
func TestSlowForwardCopyOverrun(t *testing.T) {
|
|
const base = 100
|
|
|
|
for length := 1; length < 18; length++ {
|
|
for offset := 1; offset < 18; offset++ {
|
|
highWaterMark := base
|
|
d := base
|
|
l := length
|
|
o := offset
|
|
|
|
// makeOffsetAtLeast8
|
|
for o < 8 {
|
|
if end := d + 8; highWaterMark < end {
|
|
highWaterMark = end
|
|
}
|
|
l -= o
|
|
d += o
|
|
o += o
|
|
}
|
|
|
|
// fixUpSlowForwardCopy
|
|
a := d
|
|
d += l
|
|
|
|
// finishSlowForwardCopy
|
|
for l > 0 {
|
|
if end := a + 8; highWaterMark < end {
|
|
highWaterMark = end
|
|
}
|
|
a += 8
|
|
l -= 8
|
|
}
|
|
|
|
dWant := base + length
|
|
overrun := highWaterMark - dWant
|
|
if d != dWant || overrun < 0 || 10 < overrun {
|
|
t.Errorf("length=%d, offset=%d: d and overrun: got (%d, %d), want (%d, something in [0, 10])",
|
|
length, offset, d, overrun, dWant)
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
// TestEncodeNoiseThenRepeats encodes input for which the first half is very
|
|
// incompressible and the second half is very compressible. The encoded form's
|
|
// length should be closer to 50% of the original length than 100%.
|
|
func TestEncodeNoiseThenRepeats(t *testing.T) {
|
|
for _, origLen := range []int{256 * 1024, 2048 * 1024} {
|
|
src := make([]byte, origLen)
|
|
rng := rand.New(rand.NewSource(1))
|
|
firstHalf, secondHalf := src[:origLen/2], src[origLen/2:]
|
|
for i := range firstHalf {
|
|
firstHalf[i] = uint8(rng.Intn(256))
|
|
}
|
|
for i := range secondHalf {
|
|
secondHalf[i] = uint8(i >> 8)
|
|
}
|
|
dst := Encode(nil, src)
|
|
if got, want := len(dst), origLen*3/4; got >= want {
|
|
t.Errorf("origLen=%d: got %d encoded bytes, want less than %d", origLen, got, want)
|
|
}
|
|
}
|
|
}
|
|
|
|
func TestFramingFormat(t *testing.T) {
|
|
// src is comprised of alternating 1e5-sized sequences of random
|
|
// (incompressible) bytes and repeated (compressible) bytes. 1e5 was chosen
|
|
// because it is larger than maxBlockSize (64k).
|
|
src := make([]byte, 1e6)
|
|
rng := rand.New(rand.NewSource(1))
|
|
for i := 0; i < 10; i++ {
|
|
if i%2 == 0 {
|
|
for j := 0; j < 1e5; j++ {
|
|
src[1e5*i+j] = uint8(rng.Intn(256))
|
|
}
|
|
} else {
|
|
for j := 0; j < 1e5; j++ {
|
|
src[1e5*i+j] = uint8(i)
|
|
}
|
|
}
|
|
}
|
|
|
|
buf := new(bytes.Buffer)
|
|
if _, err := NewWriter(buf).Write(src); err != nil {
|
|
t.Fatalf("Write: encoding: %v", err)
|
|
}
|
|
dst, err := ioutil.ReadAll(NewReader(buf))
|
|
if err != nil {
|
|
t.Fatalf("ReadAll: decoding: %v", err)
|
|
}
|
|
if err := cmp(dst, src); err != nil {
|
|
t.Fatal(err)
|
|
}
|
|
}
|
|
|
|
func TestWriterGoldenOutput(t *testing.T) {
|
|
buf := new(bytes.Buffer)
|
|
w := NewBufferedWriter(buf)
|
|
defer w.Close()
|
|
w.Write([]byte("abcd")) // Not compressible.
|
|
w.Flush()
|
|
w.Write(bytes.Repeat([]byte{'A'}, 150)) // Compressible.
|
|
w.Flush()
|
|
// The next chunk is also compressible, but a naive, greedy encoding of the
|
|
// overall length 67 copy as a length 64 copy (the longest expressible as a
|
|
// tagCopy1 or tagCopy2) plus a length 3 remainder would be two 3-byte
|
|
// tagCopy2 tags (6 bytes), since the minimum length for a tagCopy1 is 4
|
|
// bytes. Instead, we could do it shorter, in 5 bytes: a 3-byte tagCopy2
|
|
// (of length 60) and a 2-byte tagCopy1 (of length 7).
|
|
w.Write(bytes.Repeat([]byte{'B'}, 68))
|
|
w.Write([]byte("efC")) // Not compressible.
|
|
w.Write(bytes.Repeat([]byte{'C'}, 20)) // Compressible.
|
|
w.Write(bytes.Repeat([]byte{'B'}, 20)) // Compressible.
|
|
w.Write([]byte("g")) // Not compressible.
|
|
w.Flush()
|
|
|
|
got := buf.String()
|
|
want := strings.Join([]string{
|
|
magicChunk,
|
|
"\x01\x08\x00\x00", // Uncompressed chunk, 8 bytes long (including 4 byte checksum).
|
|
"\x68\x10\xe6\xb6", // Checksum.
|
|
"\x61\x62\x63\x64", // Uncompressed payload: "abcd".
|
|
"\x00\x11\x00\x00", // Compressed chunk, 17 bytes long (including 4 byte checksum).
|
|
"\x5f\xeb\xf2\x10", // Checksum.
|
|
"\x96\x01", // Compressed payload: Uncompressed length (varint encoded): 150.
|
|
"\x00\x41", // Compressed payload: tagLiteral, length=1, "A".
|
|
"\xfe\x01\x00", // Compressed payload: tagCopy2, length=64, offset=1.
|
|
"\xfe\x01\x00", // Compressed payload: tagCopy2, length=64, offset=1.
|
|
"\x52\x01\x00", // Compressed payload: tagCopy2, length=21, offset=1.
|
|
"\x00\x18\x00\x00", // Compressed chunk, 24 bytes long (including 4 byte checksum).
|
|
"\x30\x85\x69\xeb", // Checksum.
|
|
"\x70", // Compressed payload: Uncompressed length (varint encoded): 112.
|
|
"\x00\x42", // Compressed payload: tagLiteral, length=1, "B".
|
|
"\xee\x01\x00", // Compressed payload: tagCopy2, length=60, offset=1.
|
|
"\x0d\x01", // Compressed payload: tagCopy1, length=7, offset=1.
|
|
"\x08\x65\x66\x43", // Compressed payload: tagLiteral, length=3, "efC".
|
|
"\x4e\x01\x00", // Compressed payload: tagCopy2, length=20, offset=1.
|
|
"\x4e\x5a\x00", // Compressed payload: tagCopy2, length=20, offset=90.
|
|
"\x00\x67", // Compressed payload: tagLiteral, length=1, "g".
|
|
}, "")
|
|
if got != want {
|
|
t.Fatalf("\ngot: % x\nwant: % x", got, want)
|
|
}
|
|
}
|
|
|
|
func TestEmitLiteral(t *testing.T) {
|
|
testCases := []struct {
|
|
length int
|
|
want string
|
|
}{
|
|
{1, "\x00"},
|
|
{2, "\x04"},
|
|
{59, "\xe8"},
|
|
{60, "\xec"},
|
|
{61, "\xf0\x3c"},
|
|
{62, "\xf0\x3d"},
|
|
{254, "\xf0\xfd"},
|
|
{255, "\xf0\xfe"},
|
|
{256, "\xf0\xff"},
|
|
{257, "\xf4\x00\x01"},
|
|
{65534, "\xf4\xfd\xff"},
|
|
{65535, "\xf4\xfe\xff"},
|
|
{65536, "\xf4\xff\xff"},
|
|
}
|
|
|
|
dst := make([]byte, 70000)
|
|
nines := bytes.Repeat([]byte{0x99}, 65536)
|
|
for _, tc := range testCases {
|
|
lit := nines[:tc.length]
|
|
n := emitLiteral(dst, lit)
|
|
if !bytes.HasSuffix(dst[:n], lit) {
|
|
t.Errorf("length=%d: did not end with that many literal bytes", tc.length)
|
|
continue
|
|
}
|
|
got := string(dst[:n-tc.length])
|
|
if got != tc.want {
|
|
t.Errorf("length=%d:\ngot % x\nwant % x", tc.length, got, tc.want)
|
|
continue
|
|
}
|
|
}
|
|
}
|
|
|
|
func TestEmitCopy(t *testing.T) {
|
|
testCases := []struct {
|
|
offset int
|
|
length int
|
|
want string
|
|
}{
|
|
{8, 04, "\x01\x08"},
|
|
{8, 11, "\x1d\x08"},
|
|
{8, 12, "\x2e\x08\x00"},
|
|
{8, 13, "\x32\x08\x00"},
|
|
{8, 59, "\xea\x08\x00"},
|
|
{8, 60, "\xee\x08\x00"},
|
|
{8, 61, "\xf2\x08\x00"},
|
|
{8, 62, "\xf6\x08\x00"},
|
|
{8, 63, "\xfa\x08\x00"},
|
|
{8, 64, "\xfe\x08\x00"},
|
|
{8, 65, "\xee\x08\x00\x05\x08"},
|
|
{8, 66, "\xee\x08\x00\x09\x08"},
|
|
{8, 67, "\xee\x08\x00\x0d\x08"},
|
|
{8, 68, "\xfe\x08\x00\x01\x08"},
|
|
{8, 69, "\xfe\x08\x00\x05\x08"},
|
|
{8, 80, "\xfe\x08\x00\x3e\x08\x00"},
|
|
|
|
{256, 04, "\x21\x00"},
|
|
{256, 11, "\x3d\x00"},
|
|
{256, 12, "\x2e\x00\x01"},
|
|
{256, 13, "\x32\x00\x01"},
|
|
{256, 59, "\xea\x00\x01"},
|
|
{256, 60, "\xee\x00\x01"},
|
|
{256, 61, "\xf2\x00\x01"},
|
|
{256, 62, "\xf6\x00\x01"},
|
|
{256, 63, "\xfa\x00\x01"},
|
|
{256, 64, "\xfe\x00\x01"},
|
|
{256, 65, "\xee\x00\x01\x25\x00"},
|
|
{256, 66, "\xee\x00\x01\x29\x00"},
|
|
{256, 67, "\xee\x00\x01\x2d\x00"},
|
|
{256, 68, "\xfe\x00\x01\x21\x00"},
|
|
{256, 69, "\xfe\x00\x01\x25\x00"},
|
|
{256, 80, "\xfe\x00\x01\x3e\x00\x01"},
|
|
|
|
{2048, 04, "\x0e\x00\x08"},
|
|
{2048, 11, "\x2a\x00\x08"},
|
|
{2048, 12, "\x2e\x00\x08"},
|
|
{2048, 13, "\x32\x00\x08"},
|
|
{2048, 59, "\xea\x00\x08"},
|
|
{2048, 60, "\xee\x00\x08"},
|
|
{2048, 61, "\xf2\x00\x08"},
|
|
{2048, 62, "\xf6\x00\x08"},
|
|
{2048, 63, "\xfa\x00\x08"},
|
|
{2048, 64, "\xfe\x00\x08"},
|
|
{2048, 65, "\xee\x00\x08\x12\x00\x08"},
|
|
{2048, 66, "\xee\x00\x08\x16\x00\x08"},
|
|
{2048, 67, "\xee\x00\x08\x1a\x00\x08"},
|
|
{2048, 68, "\xfe\x00\x08\x0e\x00\x08"},
|
|
{2048, 69, "\xfe\x00\x08\x12\x00\x08"},
|
|
{2048, 80, "\xfe\x00\x08\x3e\x00\x08"},
|
|
}
|
|
|
|
dst := make([]byte, 1024)
|
|
for _, tc := range testCases {
|
|
n := emitCopy(dst, tc.offset, tc.length)
|
|
got := string(dst[:n])
|
|
if got != tc.want {
|
|
t.Errorf("offset=%d, length=%d:\ngot % x\nwant % x", tc.offset, tc.length, got, tc.want)
|
|
}
|
|
}
|
|
}
|
|
|
|
func TestNewBufferedWriter(t *testing.T) {
|
|
// Test all 32 possible sub-sequences of these 5 input slices.
|
|
//
|
|
// Their lengths sum to 400,000, which is over 6 times the Writer ibuf
|
|
// capacity: 6 * maxBlockSize is 393,216.
|
|
inputs := [][]byte{
|
|
bytes.Repeat([]byte{'a'}, 40000),
|
|
bytes.Repeat([]byte{'b'}, 150000),
|
|
bytes.Repeat([]byte{'c'}, 60000),
|
|
bytes.Repeat([]byte{'d'}, 120000),
|
|
bytes.Repeat([]byte{'e'}, 30000),
|
|
}
|
|
loop:
|
|
for i := 0; i < 1<<uint(len(inputs)); i++ {
|
|
var want []byte
|
|
buf := new(bytes.Buffer)
|
|
w := NewBufferedWriter(buf)
|
|
for j, input := range inputs {
|
|
if i&(1<<uint(j)) == 0 {
|
|
continue
|
|
}
|
|
if _, err := w.Write(input); err != nil {
|
|
t.Errorf("i=%#02x: j=%d: Write: %v", i, j, err)
|
|
continue loop
|
|
}
|
|
want = append(want, input...)
|
|
}
|
|
if err := w.Close(); err != nil {
|
|
t.Errorf("i=%#02x: Close: %v", i, err)
|
|
continue
|
|
}
|
|
got, err := ioutil.ReadAll(NewReader(buf))
|
|
if err != nil {
|
|
t.Errorf("i=%#02x: ReadAll: %v", i, err)
|
|
continue
|
|
}
|
|
if err := cmp(got, want); err != nil {
|
|
t.Errorf("i=%#02x: %v", i, err)
|
|
continue
|
|
}
|
|
}
|
|
}
|
|
|
|
func TestFlush(t *testing.T) {
|
|
buf := new(bytes.Buffer)
|
|
w := NewBufferedWriter(buf)
|
|
defer w.Close()
|
|
if _, err := w.Write(bytes.Repeat([]byte{'x'}, 20)); err != nil {
|
|
t.Fatalf("Write: %v", err)
|
|
}
|
|
if n := buf.Len(); n != 0 {
|
|
t.Fatalf("before Flush: %d bytes were written to the underlying io.Writer, want 0", n)
|
|
}
|
|
if err := w.Flush(); err != nil {
|
|
t.Fatalf("Flush: %v", err)
|
|
}
|
|
if n := buf.Len(); n == 0 {
|
|
t.Fatalf("after Flush: %d bytes were written to the underlying io.Writer, want non-0", n)
|
|
}
|
|
}
|
|
|
|
func TestReaderUncompressedDataOK(t *testing.T) {
|
|
r := NewReader(strings.NewReader(magicChunk +
|
|
"\x01\x08\x00\x00" + // Uncompressed chunk, 8 bytes long (including 4 byte checksum).
|
|
"\x68\x10\xe6\xb6" + // Checksum.
|
|
"\x61\x62\x63\x64", // Uncompressed payload: "abcd".
|
|
))
|
|
g, err := ioutil.ReadAll(r)
|
|
if err != nil {
|
|
t.Fatal(err)
|
|
}
|
|
if got, want := string(g), "abcd"; got != want {
|
|
t.Fatalf("got %q, want %q", got, want)
|
|
}
|
|
}
|
|
|
|
func TestReaderUncompressedDataNoPayload(t *testing.T) {
|
|
r := NewReader(strings.NewReader(magicChunk +
|
|
"\x01\x04\x00\x00" + // Uncompressed chunk, 4 bytes long.
|
|
"", // No payload; corrupt input.
|
|
))
|
|
if _, err := ioutil.ReadAll(r); err != ErrCorrupt {
|
|
t.Fatalf("got %v, want %v", err, ErrCorrupt)
|
|
}
|
|
}
|
|
|
|
func TestReaderUncompressedDataTooLong(t *testing.T) {
|
|
// https://github.com/google/snappy/blob/master/framing_format.txt section
|
|
// 4.3 says that "the maximum legal chunk length... is 65540", or 0x10004.
|
|
const n = 0x10005
|
|
|
|
r := NewReader(strings.NewReader(magicChunk +
|
|
"\x01\x05\x00\x01" + // Uncompressed chunk, n bytes long.
|
|
strings.Repeat("\x00", n),
|
|
))
|
|
if _, err := ioutil.ReadAll(r); err != ErrCorrupt {
|
|
t.Fatalf("got %v, want %v", err, ErrCorrupt)
|
|
}
|
|
}
|
|
|
|
func TestReaderReset(t *testing.T) {
|
|
gold := bytes.Repeat([]byte("All that is gold does not glitter,\n"), 10000)
|
|
buf := new(bytes.Buffer)
|
|
if _, err := NewWriter(buf).Write(gold); err != nil {
|
|
t.Fatalf("Write: %v", err)
|
|
}
|
|
encoded, invalid, partial := buf.String(), "invalid", "partial"
|
|
r := NewReader(nil)
|
|
for i, s := range []string{encoded, invalid, partial, encoded, partial, invalid, encoded, encoded} {
|
|
if s == partial {
|
|
r.Reset(strings.NewReader(encoded))
|
|
if _, err := r.Read(make([]byte, 101)); err != nil {
|
|
t.Errorf("#%d: %v", i, err)
|
|
continue
|
|
}
|
|
continue
|
|
}
|
|
r.Reset(strings.NewReader(s))
|
|
got, err := ioutil.ReadAll(r)
|
|
switch s {
|
|
case encoded:
|
|
if err != nil {
|
|
t.Errorf("#%d: %v", i, err)
|
|
continue
|
|
}
|
|
if err := cmp(got, gold); err != nil {
|
|
t.Errorf("#%d: %v", i, err)
|
|
continue
|
|
}
|
|
case invalid:
|
|
if err == nil {
|
|
t.Errorf("#%d: got nil error, want non-nil", i)
|
|
continue
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
func TestWriterReset(t *testing.T) {
|
|
gold := bytes.Repeat([]byte("Not all those who wander are lost;\n"), 10000)
|
|
const n = 20
|
|
for _, buffered := range []bool{false, true} {
|
|
var w *Writer
|
|
if buffered {
|
|
w = NewBufferedWriter(nil)
|
|
defer w.Close()
|
|
} else {
|
|
w = NewWriter(nil)
|
|
}
|
|
|
|
var gots, wants [][]byte
|
|
failed := false
|
|
for i := 0; i <= n; i++ {
|
|
buf := new(bytes.Buffer)
|
|
w.Reset(buf)
|
|
want := gold[:len(gold)*i/n]
|
|
if _, err := w.Write(want); err != nil {
|
|
t.Errorf("#%d: Write: %v", i, err)
|
|
failed = true
|
|
continue
|
|
}
|
|
if buffered {
|
|
if err := w.Flush(); err != nil {
|
|
t.Errorf("#%d: Flush: %v", i, err)
|
|
failed = true
|
|
continue
|
|
}
|
|
}
|
|
got, err := ioutil.ReadAll(NewReader(buf))
|
|
if err != nil {
|
|
t.Errorf("#%d: ReadAll: %v", i, err)
|
|
failed = true
|
|
continue
|
|
}
|
|
gots = append(gots, got)
|
|
wants = append(wants, want)
|
|
}
|
|
if failed {
|
|
continue
|
|
}
|
|
for i := range gots {
|
|
if err := cmp(gots[i], wants[i]); err != nil {
|
|
t.Errorf("#%d: %v", i, err)
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
func TestWriterResetWithoutFlush(t *testing.T) {
|
|
buf0 := new(bytes.Buffer)
|
|
buf1 := new(bytes.Buffer)
|
|
w := NewBufferedWriter(buf0)
|
|
if _, err := w.Write([]byte("xxx")); err != nil {
|
|
t.Fatalf("Write #0: %v", err)
|
|
}
|
|
// Note that we don't Flush the Writer before calling Reset.
|
|
w.Reset(buf1)
|
|
if _, err := w.Write([]byte("yyy")); err != nil {
|
|
t.Fatalf("Write #1: %v", err)
|
|
}
|
|
if err := w.Flush(); err != nil {
|
|
t.Fatalf("Flush: %v", err)
|
|
}
|
|
got, err := ioutil.ReadAll(NewReader(buf1))
|
|
if err != nil {
|
|
t.Fatalf("ReadAll: %v", err)
|
|
}
|
|
if err := cmp(got, []byte("yyy")); err != nil {
|
|
t.Fatal(err)
|
|
}
|
|
}
|
|
|
|
type writeCounter int
|
|
|
|
func (c *writeCounter) Write(p []byte) (int, error) {
|
|
*c++
|
|
return len(p), nil
|
|
}
|
|
|
|
// TestNumUnderlyingWrites tests that each Writer flush only makes one or two
|
|
// Write calls on its underlying io.Writer, depending on whether or not the
|
|
// flushed buffer was compressible.
|
|
func TestNumUnderlyingWrites(t *testing.T) {
|
|
testCases := []struct {
|
|
input []byte
|
|
want int
|
|
}{
|
|
{bytes.Repeat([]byte{'x'}, 100), 1},
|
|
{bytes.Repeat([]byte{'y'}, 100), 1},
|
|
{[]byte("ABCDEFGHIJKLMNOPQRST"), 2},
|
|
}
|
|
|
|
var c writeCounter
|
|
w := NewBufferedWriter(&c)
|
|
defer w.Close()
|
|
for i, tc := range testCases {
|
|
c = 0
|
|
if _, err := w.Write(tc.input); err != nil {
|
|
t.Errorf("#%d: Write: %v", i, err)
|
|
continue
|
|
}
|
|
if err := w.Flush(); err != nil {
|
|
t.Errorf("#%d: Flush: %v", i, err)
|
|
continue
|
|
}
|
|
if int(c) != tc.want {
|
|
t.Errorf("#%d: got %d underlying writes, want %d", i, c, tc.want)
|
|
continue
|
|
}
|
|
}
|
|
}
|
|
|
|
func benchDecode(b *testing.B, src []byte) {
|
|
encoded := Encode(nil, src)
|
|
// Bandwidth is in amount of uncompressed data.
|
|
b.SetBytes(int64(len(src)))
|
|
b.ResetTimer()
|
|
for i := 0; i < b.N; i++ {
|
|
Decode(src, encoded)
|
|
}
|
|
}
|
|
|
|
func benchEncode(b *testing.B, src []byte) {
|
|
// Bandwidth is in amount of uncompressed data.
|
|
b.SetBytes(int64(len(src)))
|
|
dst := make([]byte, MaxEncodedLen(len(src)))
|
|
b.ResetTimer()
|
|
for i := 0; i < b.N; i++ {
|
|
Encode(dst, src)
|
|
}
|
|
}
|
|
|
|
func testOrBenchmark(b testing.TB) string {
|
|
if _, ok := b.(*testing.B); ok {
|
|
return "benchmark"
|
|
}
|
|
return "test"
|
|
}
|
|
|
|
func readFile(b testing.TB, filename string) []byte {
|
|
src, err := ioutil.ReadFile(filename)
|
|
if err != nil {
|
|
b.Skipf("skipping %s: %v", testOrBenchmark(b), err)
|
|
}
|
|
if len(src) == 0 {
|
|
b.Fatalf("%s has zero length", filename)
|
|
}
|
|
return src
|
|
}
|
|
|
|
// expand returns a slice of length n containing repeated copies of src.
|
|
func expand(src []byte, n int) []byte {
|
|
dst := make([]byte, n)
|
|
for x := dst; len(x) > 0; {
|
|
i := copy(x, src)
|
|
x = x[i:]
|
|
}
|
|
return dst
|
|
}
|
|
|
|
func benchWords(b *testing.B, n int, decode bool) {
|
|
// Note: the file is OS-language dependent so the resulting values are not
|
|
// directly comparable for non-US-English OS installations.
|
|
data := expand(readFile(b, "/usr/share/dict/words"), n)
|
|
if decode {
|
|
benchDecode(b, data)
|
|
} else {
|
|
benchEncode(b, data)
|
|
}
|
|
}
|
|
|
|
func BenchmarkWordsDecode1e1(b *testing.B) { benchWords(b, 1e1, true) }
|
|
func BenchmarkWordsDecode1e2(b *testing.B) { benchWords(b, 1e2, true) }
|
|
func BenchmarkWordsDecode1e3(b *testing.B) { benchWords(b, 1e3, true) }
|
|
func BenchmarkWordsDecode1e4(b *testing.B) { benchWords(b, 1e4, true) }
|
|
func BenchmarkWordsDecode1e5(b *testing.B) { benchWords(b, 1e5, true) }
|
|
func BenchmarkWordsDecode1e6(b *testing.B) { benchWords(b, 1e6, true) }
|
|
func BenchmarkWordsEncode1e1(b *testing.B) { benchWords(b, 1e1, false) }
|
|
func BenchmarkWordsEncode1e2(b *testing.B) { benchWords(b, 1e2, false) }
|
|
func BenchmarkWordsEncode1e3(b *testing.B) { benchWords(b, 1e3, false) }
|
|
func BenchmarkWordsEncode1e4(b *testing.B) { benchWords(b, 1e4, false) }
|
|
func BenchmarkWordsEncode1e5(b *testing.B) { benchWords(b, 1e5, false) }
|
|
func BenchmarkWordsEncode1e6(b *testing.B) { benchWords(b, 1e6, false) }
|
|
|
|
func BenchmarkRandomEncode(b *testing.B) {
|
|
rng := rand.New(rand.NewSource(1))
|
|
data := make([]byte, 1<<20)
|
|
for i := range data {
|
|
data[i] = uint8(rng.Intn(256))
|
|
}
|
|
benchEncode(b, data)
|
|
}
|
|
|
|
// testFiles' values are copied directly from
|
|
// https://raw.githubusercontent.com/google/snappy/master/snappy_unittest.cc
|
|
// The label field is unused in snappy-go.
|
|
var testFiles = []struct {
|
|
label string
|
|
filename string
|
|
sizeLimit int
|
|
}{
|
|
{"html", "html", 0},
|
|
{"urls", "urls.10K", 0},
|
|
{"jpg", "fireworks.jpeg", 0},
|
|
{"jpg_200", "fireworks.jpeg", 200},
|
|
{"pdf", "paper-100k.pdf", 0},
|
|
{"html4", "html_x_4", 0},
|
|
{"txt1", "alice29.txt", 0},
|
|
{"txt2", "asyoulik.txt", 0},
|
|
{"txt3", "lcet10.txt", 0},
|
|
{"txt4", "plrabn12.txt", 0},
|
|
{"pb", "geo.protodata", 0},
|
|
{"gaviota", "kppkn.gtb", 0},
|
|
}
|
|
|
|
const (
|
|
// The benchmark data files are at this canonical URL.
|
|
benchURL = "https://raw.githubusercontent.com/google/snappy/master/testdata/"
|
|
)
|
|
|
|
func downloadBenchmarkFiles(b testing.TB, basename string) (errRet error) {
|
|
bDir := filepath.FromSlash(*benchdataDir)
|
|
filename := filepath.Join(bDir, basename)
|
|
if stat, err := os.Stat(filename); err == nil && stat.Size() != 0 {
|
|
return nil
|
|
}
|
|
|
|
if !*download {
|
|
b.Skipf("test data not found; skipping %s without the -download flag", testOrBenchmark(b))
|
|
}
|
|
// Download the official snappy C++ implementation reference test data
|
|
// files for benchmarking.
|
|
if err := os.MkdirAll(bDir, 0777); err != nil && !os.IsExist(err) {
|
|
return fmt.Errorf("failed to create %s: %s", bDir, err)
|
|
}
|
|
|
|
f, err := os.Create(filename)
|
|
if err != nil {
|
|
return fmt.Errorf("failed to create %s: %s", filename, err)
|
|
}
|
|
defer f.Close()
|
|
defer func() {
|
|
if errRet != nil {
|
|
os.Remove(filename)
|
|
}
|
|
}()
|
|
url := benchURL + basename
|
|
resp, err := http.Get(url)
|
|
if err != nil {
|
|
return fmt.Errorf("failed to download %s: %s", url, err)
|
|
}
|
|
defer resp.Body.Close()
|
|
if s := resp.StatusCode; s != http.StatusOK {
|
|
return fmt.Errorf("downloading %s: HTTP status code %d (%s)", url, s, http.StatusText(s))
|
|
}
|
|
_, err = io.Copy(f, resp.Body)
|
|
if err != nil {
|
|
return fmt.Errorf("failed to download %s to %s: %s", url, filename, err)
|
|
}
|
|
return nil
|
|
}
|
|
|
|
func benchFile(b *testing.B, i int, decode bool) {
|
|
if err := downloadBenchmarkFiles(b, testFiles[i].filename); err != nil {
|
|
b.Fatalf("failed to download testdata: %s", err)
|
|
}
|
|
bDir := filepath.FromSlash(*benchdataDir)
|
|
data := readFile(b, filepath.Join(bDir, testFiles[i].filename))
|
|
if n := testFiles[i].sizeLimit; 0 < n && n < len(data) {
|
|
data = data[:n]
|
|
}
|
|
if decode {
|
|
benchDecode(b, data)
|
|
} else {
|
|
benchEncode(b, data)
|
|
}
|
|
}
|
|
|
|
// Naming convention is kept similar to what snappy's C++ implementation uses.
|
|
func Benchmark_UFlat0(b *testing.B) { benchFile(b, 0, true) }
|
|
func Benchmark_UFlat1(b *testing.B) { benchFile(b, 1, true) }
|
|
func Benchmark_UFlat2(b *testing.B) { benchFile(b, 2, true) }
|
|
func Benchmark_UFlat3(b *testing.B) { benchFile(b, 3, true) }
|
|
func Benchmark_UFlat4(b *testing.B) { benchFile(b, 4, true) }
|
|
func Benchmark_UFlat5(b *testing.B) { benchFile(b, 5, true) }
|
|
func Benchmark_UFlat6(b *testing.B) { benchFile(b, 6, true) }
|
|
func Benchmark_UFlat7(b *testing.B) { benchFile(b, 7, true) }
|
|
func Benchmark_UFlat8(b *testing.B) { benchFile(b, 8, true) }
|
|
func Benchmark_UFlat9(b *testing.B) { benchFile(b, 9, true) }
|
|
func Benchmark_UFlat10(b *testing.B) { benchFile(b, 10, true) }
|
|
func Benchmark_UFlat11(b *testing.B) { benchFile(b, 11, true) }
|
|
func Benchmark_ZFlat0(b *testing.B) { benchFile(b, 0, false) }
|
|
func Benchmark_ZFlat1(b *testing.B) { benchFile(b, 1, false) }
|
|
func Benchmark_ZFlat2(b *testing.B) { benchFile(b, 2, false) }
|
|
func Benchmark_ZFlat3(b *testing.B) { benchFile(b, 3, false) }
|
|
func Benchmark_ZFlat4(b *testing.B) { benchFile(b, 4, false) }
|
|
func Benchmark_ZFlat5(b *testing.B) { benchFile(b, 5, false) }
|
|
func Benchmark_ZFlat6(b *testing.B) { benchFile(b, 6, false) }
|
|
func Benchmark_ZFlat7(b *testing.B) { benchFile(b, 7, false) }
|
|
func Benchmark_ZFlat8(b *testing.B) { benchFile(b, 8, false) }
|
|
func Benchmark_ZFlat9(b *testing.B) { benchFile(b, 9, false) }
|
|
func Benchmark_ZFlat10(b *testing.B) { benchFile(b, 10, false) }
|
|
func Benchmark_ZFlat11(b *testing.B) { benchFile(b, 11, false) }
|
|
|
|
func BenchmarkExtendMatch(b *testing.B) {
|
|
tDir := filepath.FromSlash(*testdataDir)
|
|
src, err := ioutil.ReadFile(filepath.Join(tDir, goldenText))
|
|
if err != nil {
|
|
b.Fatalf("ReadFile: %v", err)
|
|
}
|
|
b.ResetTimer()
|
|
for i := 0; i < b.N; i++ {
|
|
for _, tc := range extendMatchGoldenTestCases {
|
|
extendMatch(src, tc.i, tc.j)
|
|
}
|
|
}
|
|
}
|