dc9e069ff2
Changed `matcher.Matches(file)` to `matcher.MatchesOrParentMatches(file)`:
cli/command/image/build/context.go:95:9: SA1019: matcher.Matches is deprecated: This implementation is buggy (it only checks a single parent dir against the pattern) and will be removed soon. Use either MatchesOrParentMatches or MatchesUsingParentResults instead. (staticcheck)
return matcher.Matches(file)
^
And updated a test to match the JSON omitting empty RootFS.Type fields (in
practice, this field should never be empty in real situations, and always
be "layer"). Changed the test to use subtests to easier find which case
is failing.
full diff: 343665850e...83b51522df
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
1125 lines
30 KiB
Go
1125 lines
30 KiB
Go
// Copyright 2019+ Klaus Post. All rights reserved.
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// License information can be found in the LICENSE file.
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// Based on work by Yann Collet, released under BSD License.
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package zstd
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import "fmt"
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const (
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dFastLongTableBits = 17 // Bits used in the long match table
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dFastLongTableSize = 1 << dFastLongTableBits // Size of the table
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dFastLongTableMask = dFastLongTableSize - 1 // Mask for table indices. Redundant, but can eliminate bounds checks.
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dFastLongLen = 8 // Bytes used for table hash
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dLongTableShardCnt = 1 << (dFastLongTableBits - dictShardBits) // Number of shards in the table
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dLongTableShardSize = dFastLongTableSize / tableShardCnt // Size of an individual shard
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dFastShortTableBits = tableBits // Bits used in the short match table
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dFastShortTableSize = 1 << dFastShortTableBits // Size of the table
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dFastShortTableMask = dFastShortTableSize - 1 // Mask for table indices. Redundant, but can eliminate bounds checks.
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dFastShortLen = 5 // Bytes used for table hash
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)
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type doubleFastEncoder struct {
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fastEncoder
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longTable [dFastLongTableSize]tableEntry
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}
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type doubleFastEncoderDict struct {
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fastEncoderDict
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longTable [dFastLongTableSize]tableEntry
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dictLongTable []tableEntry
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longTableShardDirty [dLongTableShardCnt]bool
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}
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// Encode mimmics functionality in zstd_dfast.c
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func (e *doubleFastEncoder) Encode(blk *blockEnc, src []byte) {
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const (
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// Input margin is the number of bytes we read (8)
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// and the maximum we will read ahead (2)
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inputMargin = 8 + 2
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minNonLiteralBlockSize = 16
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)
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// Protect against e.cur wraparound.
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for e.cur >= bufferReset {
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if len(e.hist) == 0 {
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for i := range e.table[:] {
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e.table[i] = tableEntry{}
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}
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for i := range e.longTable[:] {
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e.longTable[i] = tableEntry{}
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}
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e.cur = e.maxMatchOff
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break
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}
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// Shift down everything in the table that isn't already too far away.
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minOff := e.cur + int32(len(e.hist)) - e.maxMatchOff
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for i := range e.table[:] {
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v := e.table[i].offset
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if v < minOff {
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v = 0
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} else {
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v = v - e.cur + e.maxMatchOff
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}
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e.table[i].offset = v
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}
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for i := range e.longTable[:] {
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v := e.longTable[i].offset
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if v < minOff {
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v = 0
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} else {
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v = v - e.cur + e.maxMatchOff
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}
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e.longTable[i].offset = v
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}
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e.cur = e.maxMatchOff
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break
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}
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s := e.addBlock(src)
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blk.size = len(src)
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if len(src) < minNonLiteralBlockSize {
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blk.extraLits = len(src)
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blk.literals = blk.literals[:len(src)]
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copy(blk.literals, src)
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return
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}
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// Override src
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src = e.hist
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sLimit := int32(len(src)) - inputMargin
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// stepSize is the number of bytes to skip on every main loop iteration.
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// It should be >= 1.
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const stepSize = 1
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const kSearchStrength = 8
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// nextEmit is where in src the next emitLiteral should start from.
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nextEmit := s
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cv := load6432(src, s)
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// Relative offsets
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offset1 := int32(blk.recentOffsets[0])
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offset2 := int32(blk.recentOffsets[1])
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addLiterals := func(s *seq, until int32) {
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if until == nextEmit {
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return
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}
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blk.literals = append(blk.literals, src[nextEmit:until]...)
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s.litLen = uint32(until - nextEmit)
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}
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if debugEncoder {
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println("recent offsets:", blk.recentOffsets)
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}
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encodeLoop:
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for {
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var t int32
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// We allow the encoder to optionally turn off repeat offsets across blocks
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canRepeat := len(blk.sequences) > 2
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for {
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if debugAsserts && canRepeat && offset1 == 0 {
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panic("offset0 was 0")
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}
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nextHashS := hashLen(cv, dFastShortTableBits, dFastShortLen)
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nextHashL := hashLen(cv, dFastLongTableBits, dFastLongLen)
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candidateL := e.longTable[nextHashL]
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candidateS := e.table[nextHashS]
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const repOff = 1
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repIndex := s - offset1 + repOff
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entry := tableEntry{offset: s + e.cur, val: uint32(cv)}
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e.longTable[nextHashL] = entry
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e.table[nextHashS] = entry
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if canRepeat {
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if repIndex >= 0 && load3232(src, repIndex) == uint32(cv>>(repOff*8)) {
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// Consider history as well.
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var seq seq
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lenght := 4 + e.matchlen(s+4+repOff, repIndex+4, src)
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seq.matchLen = uint32(lenght - zstdMinMatch)
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// We might be able to match backwards.
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// Extend as long as we can.
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start := s + repOff
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// We end the search early, so we don't risk 0 literals
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// and have to do special offset treatment.
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startLimit := nextEmit + 1
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tMin := s - e.maxMatchOff
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if tMin < 0 {
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tMin = 0
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}
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for repIndex > tMin && start > startLimit && src[repIndex-1] == src[start-1] && seq.matchLen < maxMatchLength-zstdMinMatch-1 {
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repIndex--
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start--
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seq.matchLen++
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}
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addLiterals(&seq, start)
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// rep 0
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seq.offset = 1
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if debugSequences {
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println("repeat sequence", seq, "next s:", s)
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}
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blk.sequences = append(blk.sequences, seq)
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s += lenght + repOff
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nextEmit = s
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if s >= sLimit {
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if debugEncoder {
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println("repeat ended", s, lenght)
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}
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break encodeLoop
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}
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cv = load6432(src, s)
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continue
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}
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}
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// Find the offsets of our two matches.
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coffsetL := s - (candidateL.offset - e.cur)
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coffsetS := s - (candidateS.offset - e.cur)
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// Check if we have a long match.
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if coffsetL < e.maxMatchOff && uint32(cv) == candidateL.val {
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// Found a long match, likely at least 8 bytes.
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// Reference encoder checks all 8 bytes, we only check 4,
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// but the likelihood of both the first 4 bytes and the hash matching should be enough.
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t = candidateL.offset - e.cur
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if debugAsserts && s <= t {
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panic(fmt.Sprintf("s (%d) <= t (%d)", s, t))
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}
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if debugAsserts && s-t > e.maxMatchOff {
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panic("s - t >e.maxMatchOff")
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}
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if debugMatches {
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println("long match")
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}
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break
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}
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// Check if we have a short match.
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if coffsetS < e.maxMatchOff && uint32(cv) == candidateS.val {
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// found a regular match
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// See if we can find a long match at s+1
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const checkAt = 1
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cv := load6432(src, s+checkAt)
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nextHashL = hashLen(cv, dFastLongTableBits, dFastLongLen)
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candidateL = e.longTable[nextHashL]
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coffsetL = s - (candidateL.offset - e.cur) + checkAt
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// We can store it, since we have at least a 4 byte match.
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e.longTable[nextHashL] = tableEntry{offset: s + checkAt + e.cur, val: uint32(cv)}
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if coffsetL < e.maxMatchOff && uint32(cv) == candidateL.val {
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// Found a long match, likely at least 8 bytes.
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// Reference encoder checks all 8 bytes, we only check 4,
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// but the likelihood of both the first 4 bytes and the hash matching should be enough.
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t = candidateL.offset - e.cur
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s += checkAt
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if debugMatches {
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println("long match (after short)")
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}
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break
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}
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t = candidateS.offset - e.cur
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if debugAsserts && s <= t {
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panic(fmt.Sprintf("s (%d) <= t (%d)", s, t))
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}
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if debugAsserts && s-t > e.maxMatchOff {
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panic("s - t >e.maxMatchOff")
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}
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if debugAsserts && t < 0 {
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panic("t<0")
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}
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if debugMatches {
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println("short match")
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}
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break
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}
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// No match found, move forward in input.
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s += stepSize + ((s - nextEmit) >> (kSearchStrength - 1))
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if s >= sLimit {
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break encodeLoop
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}
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cv = load6432(src, s)
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}
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// A 4-byte match has been found. Update recent offsets.
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// We'll later see if more than 4 bytes.
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offset2 = offset1
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offset1 = s - t
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if debugAsserts && s <= t {
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panic(fmt.Sprintf("s (%d) <= t (%d)", s, t))
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}
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if debugAsserts && canRepeat && int(offset1) > len(src) {
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panic("invalid offset")
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}
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// Extend the 4-byte match as long as possible.
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l := e.matchlen(s+4, t+4, src) + 4
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// Extend backwards
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tMin := s - e.maxMatchOff
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if tMin < 0 {
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tMin = 0
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}
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for t > tMin && s > nextEmit && src[t-1] == src[s-1] && l < maxMatchLength {
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s--
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t--
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l++
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}
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// Write our sequence
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var seq seq
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seq.litLen = uint32(s - nextEmit)
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seq.matchLen = uint32(l - zstdMinMatch)
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if seq.litLen > 0 {
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blk.literals = append(blk.literals, src[nextEmit:s]...)
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}
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seq.offset = uint32(s-t) + 3
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s += l
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if debugSequences {
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println("sequence", seq, "next s:", s)
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}
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blk.sequences = append(blk.sequences, seq)
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nextEmit = s
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if s >= sLimit {
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break encodeLoop
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}
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// Index match start+1 (long) and start+2 (short)
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index0 := s - l + 1
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// Index match end-2 (long) and end-1 (short)
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index1 := s - 2
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cv0 := load6432(src, index0)
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cv1 := load6432(src, index1)
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te0 := tableEntry{offset: index0 + e.cur, val: uint32(cv0)}
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te1 := tableEntry{offset: index1 + e.cur, val: uint32(cv1)}
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e.longTable[hashLen(cv0, dFastLongTableBits, dFastLongLen)] = te0
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e.longTable[hashLen(cv1, dFastLongTableBits, dFastLongLen)] = te1
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cv0 >>= 8
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cv1 >>= 8
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te0.offset++
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te1.offset++
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te0.val = uint32(cv0)
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te1.val = uint32(cv1)
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e.table[hashLen(cv0, dFastShortTableBits, dFastShortLen)] = te0
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e.table[hashLen(cv1, dFastShortTableBits, dFastShortLen)] = te1
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cv = load6432(src, s)
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if !canRepeat {
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continue
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}
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// Check offset 2
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for {
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o2 := s - offset2
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if load3232(src, o2) != uint32(cv) {
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// Do regular search
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break
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}
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// Store this, since we have it.
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nextHashS := hashLen(cv, dFastShortTableBits, dFastShortLen)
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nextHashL := hashLen(cv, dFastLongTableBits, dFastLongLen)
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// We have at least 4 byte match.
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// No need to check backwards. We come straight from a match
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l := 4 + e.matchlen(s+4, o2+4, src)
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entry := tableEntry{offset: s + e.cur, val: uint32(cv)}
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e.longTable[nextHashL] = entry
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e.table[nextHashS] = entry
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seq.matchLen = uint32(l) - zstdMinMatch
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seq.litLen = 0
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// Since litlen is always 0, this is offset 1.
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seq.offset = 1
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s += l
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nextEmit = s
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if debugSequences {
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println("sequence", seq, "next s:", s)
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}
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blk.sequences = append(blk.sequences, seq)
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// Swap offset 1 and 2.
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offset1, offset2 = offset2, offset1
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if s >= sLimit {
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// Finished
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break encodeLoop
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}
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cv = load6432(src, s)
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}
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}
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if int(nextEmit) < len(src) {
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blk.literals = append(blk.literals, src[nextEmit:]...)
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blk.extraLits = len(src) - int(nextEmit)
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}
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blk.recentOffsets[0] = uint32(offset1)
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blk.recentOffsets[1] = uint32(offset2)
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if debugEncoder {
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println("returning, recent offsets:", blk.recentOffsets, "extra literals:", blk.extraLits)
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}
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}
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// EncodeNoHist will encode a block with no history and no following blocks.
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// Most notable difference is that src will not be copied for history and
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// we do not need to check for max match length.
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func (e *doubleFastEncoder) EncodeNoHist(blk *blockEnc, src []byte) {
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const (
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// Input margin is the number of bytes we read (8)
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// and the maximum we will read ahead (2)
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inputMargin = 8 + 2
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minNonLiteralBlockSize = 16
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)
|
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|
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// Protect against e.cur wraparound.
|
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if e.cur >= bufferReset {
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for i := range e.table[:] {
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e.table[i] = tableEntry{}
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}
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for i := range e.longTable[:] {
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e.longTable[i] = tableEntry{}
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}
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e.cur = e.maxMatchOff
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}
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|
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s := int32(0)
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blk.size = len(src)
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if len(src) < minNonLiteralBlockSize {
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blk.extraLits = len(src)
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blk.literals = blk.literals[:len(src)]
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copy(blk.literals, src)
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return
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}
|
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|
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// Override src
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sLimit := int32(len(src)) - inputMargin
|
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// stepSize is the number of bytes to skip on every main loop iteration.
|
|
// It should be >= 1.
|
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const stepSize = 1
|
|
|
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const kSearchStrength = 8
|
|
|
|
// nextEmit is where in src the next emitLiteral should start from.
|
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nextEmit := s
|
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cv := load6432(src, s)
|
|
|
|
// Relative offsets
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offset1 := int32(blk.recentOffsets[0])
|
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offset2 := int32(blk.recentOffsets[1])
|
|
|
|
addLiterals := func(s *seq, until int32) {
|
|
if until == nextEmit {
|
|
return
|
|
}
|
|
blk.literals = append(blk.literals, src[nextEmit:until]...)
|
|
s.litLen = uint32(until - nextEmit)
|
|
}
|
|
if debugEncoder {
|
|
println("recent offsets:", blk.recentOffsets)
|
|
}
|
|
|
|
encodeLoop:
|
|
for {
|
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var t int32
|
|
for {
|
|
|
|
nextHashS := hashLen(cv, dFastShortTableBits, dFastShortLen)
|
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nextHashL := hashLen(cv, dFastLongTableBits, dFastLongLen)
|
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candidateL := e.longTable[nextHashL]
|
|
candidateS := e.table[nextHashS]
|
|
|
|
const repOff = 1
|
|
repIndex := s - offset1 + repOff
|
|
entry := tableEntry{offset: s + e.cur, val: uint32(cv)}
|
|
e.longTable[nextHashL] = entry
|
|
e.table[nextHashS] = entry
|
|
|
|
if len(blk.sequences) > 2 {
|
|
if load3232(src, repIndex) == uint32(cv>>(repOff*8)) {
|
|
// Consider history as well.
|
|
var seq seq
|
|
//length := 4 + e.matchlen(s+4+repOff, repIndex+4, src)
|
|
length := 4 + int32(matchLen(src[s+4+repOff:], src[repIndex+4:]))
|
|
|
|
seq.matchLen = uint32(length - zstdMinMatch)
|
|
|
|
// We might be able to match backwards.
|
|
// Extend as long as we can.
|
|
start := s + repOff
|
|
// We end the search early, so we don't risk 0 literals
|
|
// and have to do special offset treatment.
|
|
startLimit := nextEmit + 1
|
|
|
|
tMin := s - e.maxMatchOff
|
|
if tMin < 0 {
|
|
tMin = 0
|
|
}
|
|
for repIndex > tMin && start > startLimit && src[repIndex-1] == src[start-1] {
|
|
repIndex--
|
|
start--
|
|
seq.matchLen++
|
|
}
|
|
addLiterals(&seq, start)
|
|
|
|
// rep 0
|
|
seq.offset = 1
|
|
if debugSequences {
|
|
println("repeat sequence", seq, "next s:", s)
|
|
}
|
|
blk.sequences = append(blk.sequences, seq)
|
|
s += length + repOff
|
|
nextEmit = s
|
|
if s >= sLimit {
|
|
if debugEncoder {
|
|
println("repeat ended", s, length)
|
|
|
|
}
|
|
break encodeLoop
|
|
}
|
|
cv = load6432(src, s)
|
|
continue
|
|
}
|
|
}
|
|
// Find the offsets of our two matches.
|
|
coffsetL := s - (candidateL.offset - e.cur)
|
|
coffsetS := s - (candidateS.offset - e.cur)
|
|
|
|
// Check if we have a long match.
|
|
if coffsetL < e.maxMatchOff && uint32(cv) == candidateL.val {
|
|
// Found a long match, likely at least 8 bytes.
|
|
// Reference encoder checks all 8 bytes, we only check 4,
|
|
// but the likelihood of both the first 4 bytes and the hash matching should be enough.
|
|
t = candidateL.offset - e.cur
|
|
if debugAsserts && s <= t {
|
|
panic(fmt.Sprintf("s (%d) <= t (%d). cur: %d", s, t, e.cur))
|
|
}
|
|
if debugAsserts && s-t > e.maxMatchOff {
|
|
panic("s - t >e.maxMatchOff")
|
|
}
|
|
if debugMatches {
|
|
println("long match")
|
|
}
|
|
break
|
|
}
|
|
|
|
// Check if we have a short match.
|
|
if coffsetS < e.maxMatchOff && uint32(cv) == candidateS.val {
|
|
// found a regular match
|
|
// See if we can find a long match at s+1
|
|
const checkAt = 1
|
|
cv := load6432(src, s+checkAt)
|
|
nextHashL = hashLen(cv, dFastLongTableBits, dFastLongLen)
|
|
candidateL = e.longTable[nextHashL]
|
|
coffsetL = s - (candidateL.offset - e.cur) + checkAt
|
|
|
|
// We can store it, since we have at least a 4 byte match.
|
|
e.longTable[nextHashL] = tableEntry{offset: s + checkAt + e.cur, val: uint32(cv)}
|
|
if coffsetL < e.maxMatchOff && uint32(cv) == candidateL.val {
|
|
// Found a long match, likely at least 8 bytes.
|
|
// Reference encoder checks all 8 bytes, we only check 4,
|
|
// but the likelihood of both the first 4 bytes and the hash matching should be enough.
|
|
t = candidateL.offset - e.cur
|
|
s += checkAt
|
|
if debugMatches {
|
|
println("long match (after short)")
|
|
}
|
|
break
|
|
}
|
|
|
|
t = candidateS.offset - e.cur
|
|
if debugAsserts && s <= t {
|
|
panic(fmt.Sprintf("s (%d) <= t (%d)", s, t))
|
|
}
|
|
if debugAsserts && s-t > e.maxMatchOff {
|
|
panic("s - t >e.maxMatchOff")
|
|
}
|
|
if debugAsserts && t < 0 {
|
|
panic("t<0")
|
|
}
|
|
if debugMatches {
|
|
println("short match")
|
|
}
|
|
break
|
|
}
|
|
|
|
// No match found, move forward in input.
|
|
s += stepSize + ((s - nextEmit) >> (kSearchStrength - 1))
|
|
if s >= sLimit {
|
|
break encodeLoop
|
|
}
|
|
cv = load6432(src, s)
|
|
}
|
|
|
|
// A 4-byte match has been found. Update recent offsets.
|
|
// We'll later see if more than 4 bytes.
|
|
offset2 = offset1
|
|
offset1 = s - t
|
|
|
|
if debugAsserts && s <= t {
|
|
panic(fmt.Sprintf("s (%d) <= t (%d)", s, t))
|
|
}
|
|
|
|
// Extend the 4-byte match as long as possible.
|
|
//l := e.matchlen(s+4, t+4, src) + 4
|
|
l := int32(matchLen(src[s+4:], src[t+4:])) + 4
|
|
|
|
// Extend backwards
|
|
tMin := s - e.maxMatchOff
|
|
if tMin < 0 {
|
|
tMin = 0
|
|
}
|
|
for t > tMin && s > nextEmit && src[t-1] == src[s-1] {
|
|
s--
|
|
t--
|
|
l++
|
|
}
|
|
|
|
// Write our sequence
|
|
var seq seq
|
|
seq.litLen = uint32(s - nextEmit)
|
|
seq.matchLen = uint32(l - zstdMinMatch)
|
|
if seq.litLen > 0 {
|
|
blk.literals = append(blk.literals, src[nextEmit:s]...)
|
|
}
|
|
seq.offset = uint32(s-t) + 3
|
|
s += l
|
|
if debugSequences {
|
|
println("sequence", seq, "next s:", s)
|
|
}
|
|
blk.sequences = append(blk.sequences, seq)
|
|
nextEmit = s
|
|
if s >= sLimit {
|
|
break encodeLoop
|
|
}
|
|
|
|
// Index match start+1 (long) and start+2 (short)
|
|
index0 := s - l + 1
|
|
// Index match end-2 (long) and end-1 (short)
|
|
index1 := s - 2
|
|
|
|
cv0 := load6432(src, index0)
|
|
cv1 := load6432(src, index1)
|
|
te0 := tableEntry{offset: index0 + e.cur, val: uint32(cv0)}
|
|
te1 := tableEntry{offset: index1 + e.cur, val: uint32(cv1)}
|
|
e.longTable[hashLen(cv0, dFastLongTableBits, dFastLongLen)] = te0
|
|
e.longTable[hashLen(cv1, dFastLongTableBits, dFastLongLen)] = te1
|
|
cv0 >>= 8
|
|
cv1 >>= 8
|
|
te0.offset++
|
|
te1.offset++
|
|
te0.val = uint32(cv0)
|
|
te1.val = uint32(cv1)
|
|
e.table[hashLen(cv0, dFastShortTableBits, dFastShortLen)] = te0
|
|
e.table[hashLen(cv1, dFastShortTableBits, dFastShortLen)] = te1
|
|
|
|
cv = load6432(src, s)
|
|
|
|
if len(blk.sequences) <= 2 {
|
|
continue
|
|
}
|
|
|
|
// Check offset 2
|
|
for {
|
|
o2 := s - offset2
|
|
if load3232(src, o2) != uint32(cv) {
|
|
// Do regular search
|
|
break
|
|
}
|
|
|
|
// Store this, since we have it.
|
|
nextHashS := hashLen(cv1>>8, dFastShortTableBits, dFastShortLen)
|
|
nextHashL := hashLen(cv, dFastLongTableBits, dFastLongLen)
|
|
|
|
// We have at least 4 byte match.
|
|
// No need to check backwards. We come straight from a match
|
|
//l := 4 + e.matchlen(s+4, o2+4, src)
|
|
l := 4 + int32(matchLen(src[s+4:], src[o2+4:]))
|
|
|
|
entry := tableEntry{offset: s + e.cur, val: uint32(cv)}
|
|
e.longTable[nextHashL] = entry
|
|
e.table[nextHashS] = entry
|
|
seq.matchLen = uint32(l) - zstdMinMatch
|
|
seq.litLen = 0
|
|
|
|
// Since litlen is always 0, this is offset 1.
|
|
seq.offset = 1
|
|
s += l
|
|
nextEmit = s
|
|
if debugSequences {
|
|
println("sequence", seq, "next s:", s)
|
|
}
|
|
blk.sequences = append(blk.sequences, seq)
|
|
|
|
// Swap offset 1 and 2.
|
|
offset1, offset2 = offset2, offset1
|
|
if s >= sLimit {
|
|
// Finished
|
|
break encodeLoop
|
|
}
|
|
cv = load6432(src, s)
|
|
}
|
|
}
|
|
|
|
if int(nextEmit) < len(src) {
|
|
blk.literals = append(blk.literals, src[nextEmit:]...)
|
|
blk.extraLits = len(src) - int(nextEmit)
|
|
}
|
|
if debugEncoder {
|
|
println("returning, recent offsets:", blk.recentOffsets, "extra literals:", blk.extraLits)
|
|
}
|
|
|
|
// We do not store history, so we must offset e.cur to avoid false matches for next user.
|
|
if e.cur < bufferReset {
|
|
e.cur += int32(len(src))
|
|
}
|
|
}
|
|
|
|
// Encode will encode the content, with a dictionary if initialized for it.
|
|
func (e *doubleFastEncoderDict) Encode(blk *blockEnc, src []byte) {
|
|
const (
|
|
// Input margin is the number of bytes we read (8)
|
|
// and the maximum we will read ahead (2)
|
|
inputMargin = 8 + 2
|
|
minNonLiteralBlockSize = 16
|
|
)
|
|
|
|
// Protect against e.cur wraparound.
|
|
for e.cur >= bufferReset {
|
|
if len(e.hist) == 0 {
|
|
for i := range e.table[:] {
|
|
e.table[i] = tableEntry{}
|
|
}
|
|
for i := range e.longTable[:] {
|
|
e.longTable[i] = tableEntry{}
|
|
}
|
|
e.markAllShardsDirty()
|
|
e.cur = e.maxMatchOff
|
|
break
|
|
}
|
|
// Shift down everything in the table that isn't already too far away.
|
|
minOff := e.cur + int32(len(e.hist)) - e.maxMatchOff
|
|
for i := range e.table[:] {
|
|
v := e.table[i].offset
|
|
if v < minOff {
|
|
v = 0
|
|
} else {
|
|
v = v - e.cur + e.maxMatchOff
|
|
}
|
|
e.table[i].offset = v
|
|
}
|
|
for i := range e.longTable[:] {
|
|
v := e.longTable[i].offset
|
|
if v < minOff {
|
|
v = 0
|
|
} else {
|
|
v = v - e.cur + e.maxMatchOff
|
|
}
|
|
e.longTable[i].offset = v
|
|
}
|
|
e.markAllShardsDirty()
|
|
e.cur = e.maxMatchOff
|
|
break
|
|
}
|
|
|
|
s := e.addBlock(src)
|
|
blk.size = len(src)
|
|
if len(src) < minNonLiteralBlockSize {
|
|
blk.extraLits = len(src)
|
|
blk.literals = blk.literals[:len(src)]
|
|
copy(blk.literals, src)
|
|
return
|
|
}
|
|
|
|
// Override src
|
|
src = e.hist
|
|
sLimit := int32(len(src)) - inputMargin
|
|
// stepSize is the number of bytes to skip on every main loop iteration.
|
|
// It should be >= 1.
|
|
const stepSize = 1
|
|
|
|
const kSearchStrength = 8
|
|
|
|
// nextEmit is where in src the next emitLiteral should start from.
|
|
nextEmit := s
|
|
cv := load6432(src, s)
|
|
|
|
// Relative offsets
|
|
offset1 := int32(blk.recentOffsets[0])
|
|
offset2 := int32(blk.recentOffsets[1])
|
|
|
|
addLiterals := func(s *seq, until int32) {
|
|
if until == nextEmit {
|
|
return
|
|
}
|
|
blk.literals = append(blk.literals, src[nextEmit:until]...)
|
|
s.litLen = uint32(until - nextEmit)
|
|
}
|
|
if debugEncoder {
|
|
println("recent offsets:", blk.recentOffsets)
|
|
}
|
|
|
|
encodeLoop:
|
|
for {
|
|
var t int32
|
|
// We allow the encoder to optionally turn off repeat offsets across blocks
|
|
canRepeat := len(blk.sequences) > 2
|
|
|
|
for {
|
|
if debugAsserts && canRepeat && offset1 == 0 {
|
|
panic("offset0 was 0")
|
|
}
|
|
|
|
nextHashS := hashLen(cv, dFastShortTableBits, dFastShortLen)
|
|
nextHashL := hashLen(cv, dFastLongTableBits, dFastLongLen)
|
|
candidateL := e.longTable[nextHashL]
|
|
candidateS := e.table[nextHashS]
|
|
|
|
const repOff = 1
|
|
repIndex := s - offset1 + repOff
|
|
entry := tableEntry{offset: s + e.cur, val: uint32(cv)}
|
|
e.longTable[nextHashL] = entry
|
|
e.markLongShardDirty(nextHashL)
|
|
e.table[nextHashS] = entry
|
|
e.markShardDirty(nextHashS)
|
|
|
|
if canRepeat {
|
|
if repIndex >= 0 && load3232(src, repIndex) == uint32(cv>>(repOff*8)) {
|
|
// Consider history as well.
|
|
var seq seq
|
|
lenght := 4 + e.matchlen(s+4+repOff, repIndex+4, src)
|
|
|
|
seq.matchLen = uint32(lenght - zstdMinMatch)
|
|
|
|
// We might be able to match backwards.
|
|
// Extend as long as we can.
|
|
start := s + repOff
|
|
// We end the search early, so we don't risk 0 literals
|
|
// and have to do special offset treatment.
|
|
startLimit := nextEmit + 1
|
|
|
|
tMin := s - e.maxMatchOff
|
|
if tMin < 0 {
|
|
tMin = 0
|
|
}
|
|
for repIndex > tMin && start > startLimit && src[repIndex-1] == src[start-1] && seq.matchLen < maxMatchLength-zstdMinMatch-1 {
|
|
repIndex--
|
|
start--
|
|
seq.matchLen++
|
|
}
|
|
addLiterals(&seq, start)
|
|
|
|
// rep 0
|
|
seq.offset = 1
|
|
if debugSequences {
|
|
println("repeat sequence", seq, "next s:", s)
|
|
}
|
|
blk.sequences = append(blk.sequences, seq)
|
|
s += lenght + repOff
|
|
nextEmit = s
|
|
if s >= sLimit {
|
|
if debugEncoder {
|
|
println("repeat ended", s, lenght)
|
|
|
|
}
|
|
break encodeLoop
|
|
}
|
|
cv = load6432(src, s)
|
|
continue
|
|
}
|
|
}
|
|
// Find the offsets of our two matches.
|
|
coffsetL := s - (candidateL.offset - e.cur)
|
|
coffsetS := s - (candidateS.offset - e.cur)
|
|
|
|
// Check if we have a long match.
|
|
if coffsetL < e.maxMatchOff && uint32(cv) == candidateL.val {
|
|
// Found a long match, likely at least 8 bytes.
|
|
// Reference encoder checks all 8 bytes, we only check 4,
|
|
// but the likelihood of both the first 4 bytes and the hash matching should be enough.
|
|
t = candidateL.offset - e.cur
|
|
if debugAsserts && s <= t {
|
|
panic(fmt.Sprintf("s (%d) <= t (%d)", s, t))
|
|
}
|
|
if debugAsserts && s-t > e.maxMatchOff {
|
|
panic("s - t >e.maxMatchOff")
|
|
}
|
|
if debugMatches {
|
|
println("long match")
|
|
}
|
|
break
|
|
}
|
|
|
|
// Check if we have a short match.
|
|
if coffsetS < e.maxMatchOff && uint32(cv) == candidateS.val {
|
|
// found a regular match
|
|
// See if we can find a long match at s+1
|
|
const checkAt = 1
|
|
cv := load6432(src, s+checkAt)
|
|
nextHashL = hashLen(cv, dFastLongTableBits, dFastLongLen)
|
|
candidateL = e.longTable[nextHashL]
|
|
coffsetL = s - (candidateL.offset - e.cur) + checkAt
|
|
|
|
// We can store it, since we have at least a 4 byte match.
|
|
e.longTable[nextHashL] = tableEntry{offset: s + checkAt + e.cur, val: uint32(cv)}
|
|
e.markLongShardDirty(nextHashL)
|
|
if coffsetL < e.maxMatchOff && uint32(cv) == candidateL.val {
|
|
// Found a long match, likely at least 8 bytes.
|
|
// Reference encoder checks all 8 bytes, we only check 4,
|
|
// but the likelihood of both the first 4 bytes and the hash matching should be enough.
|
|
t = candidateL.offset - e.cur
|
|
s += checkAt
|
|
if debugMatches {
|
|
println("long match (after short)")
|
|
}
|
|
break
|
|
}
|
|
|
|
t = candidateS.offset - e.cur
|
|
if debugAsserts && s <= t {
|
|
panic(fmt.Sprintf("s (%d) <= t (%d)", s, t))
|
|
}
|
|
if debugAsserts && s-t > e.maxMatchOff {
|
|
panic("s - t >e.maxMatchOff")
|
|
}
|
|
if debugAsserts && t < 0 {
|
|
panic("t<0")
|
|
}
|
|
if debugMatches {
|
|
println("short match")
|
|
}
|
|
break
|
|
}
|
|
|
|
// No match found, move forward in input.
|
|
s += stepSize + ((s - nextEmit) >> (kSearchStrength - 1))
|
|
if s >= sLimit {
|
|
break encodeLoop
|
|
}
|
|
cv = load6432(src, s)
|
|
}
|
|
|
|
// A 4-byte match has been found. Update recent offsets.
|
|
// We'll later see if more than 4 bytes.
|
|
offset2 = offset1
|
|
offset1 = s - t
|
|
|
|
if debugAsserts && s <= t {
|
|
panic(fmt.Sprintf("s (%d) <= t (%d)", s, t))
|
|
}
|
|
|
|
if debugAsserts && canRepeat && int(offset1) > len(src) {
|
|
panic("invalid offset")
|
|
}
|
|
|
|
// Extend the 4-byte match as long as possible.
|
|
l := e.matchlen(s+4, t+4, src) + 4
|
|
|
|
// Extend backwards
|
|
tMin := s - e.maxMatchOff
|
|
if tMin < 0 {
|
|
tMin = 0
|
|
}
|
|
for t > tMin && s > nextEmit && src[t-1] == src[s-1] && l < maxMatchLength {
|
|
s--
|
|
t--
|
|
l++
|
|
}
|
|
|
|
// Write our sequence
|
|
var seq seq
|
|
seq.litLen = uint32(s - nextEmit)
|
|
seq.matchLen = uint32(l - zstdMinMatch)
|
|
if seq.litLen > 0 {
|
|
blk.literals = append(blk.literals, src[nextEmit:s]...)
|
|
}
|
|
seq.offset = uint32(s-t) + 3
|
|
s += l
|
|
if debugSequences {
|
|
println("sequence", seq, "next s:", s)
|
|
}
|
|
blk.sequences = append(blk.sequences, seq)
|
|
nextEmit = s
|
|
if s >= sLimit {
|
|
break encodeLoop
|
|
}
|
|
|
|
// Index match start+1 (long) and start+2 (short)
|
|
index0 := s - l + 1
|
|
// Index match end-2 (long) and end-1 (short)
|
|
index1 := s - 2
|
|
|
|
cv0 := load6432(src, index0)
|
|
cv1 := load6432(src, index1)
|
|
te0 := tableEntry{offset: index0 + e.cur, val: uint32(cv0)}
|
|
te1 := tableEntry{offset: index1 + e.cur, val: uint32(cv1)}
|
|
longHash1 := hashLen(cv0, dFastLongTableBits, dFastLongLen)
|
|
longHash2 := hashLen(cv0, dFastLongTableBits, dFastLongLen)
|
|
e.longTable[longHash1] = te0
|
|
e.longTable[longHash2] = te1
|
|
e.markLongShardDirty(longHash1)
|
|
e.markLongShardDirty(longHash2)
|
|
cv0 >>= 8
|
|
cv1 >>= 8
|
|
te0.offset++
|
|
te1.offset++
|
|
te0.val = uint32(cv0)
|
|
te1.val = uint32(cv1)
|
|
hashVal1 := hashLen(cv0, dFastShortTableBits, dFastShortLen)
|
|
hashVal2 := hashLen(cv1, dFastShortTableBits, dFastShortLen)
|
|
e.table[hashVal1] = te0
|
|
e.markShardDirty(hashVal1)
|
|
e.table[hashVal2] = te1
|
|
e.markShardDirty(hashVal2)
|
|
|
|
cv = load6432(src, s)
|
|
|
|
if !canRepeat {
|
|
continue
|
|
}
|
|
|
|
// Check offset 2
|
|
for {
|
|
o2 := s - offset2
|
|
if load3232(src, o2) != uint32(cv) {
|
|
// Do regular search
|
|
break
|
|
}
|
|
|
|
// Store this, since we have it.
|
|
nextHashS := hashLen(cv, dFastShortTableBits, dFastShortLen)
|
|
nextHashL := hashLen(cv, dFastLongTableBits, dFastLongLen)
|
|
|
|
// We have at least 4 byte match.
|
|
// No need to check backwards. We come straight from a match
|
|
l := 4 + e.matchlen(s+4, o2+4, src)
|
|
|
|
entry := tableEntry{offset: s + e.cur, val: uint32(cv)}
|
|
e.longTable[nextHashL] = entry
|
|
e.markLongShardDirty(nextHashL)
|
|
e.table[nextHashS] = entry
|
|
e.markShardDirty(nextHashS)
|
|
seq.matchLen = uint32(l) - zstdMinMatch
|
|
seq.litLen = 0
|
|
|
|
// Since litlen is always 0, this is offset 1.
|
|
seq.offset = 1
|
|
s += l
|
|
nextEmit = s
|
|
if debugSequences {
|
|
println("sequence", seq, "next s:", s)
|
|
}
|
|
blk.sequences = append(blk.sequences, seq)
|
|
|
|
// Swap offset 1 and 2.
|
|
offset1, offset2 = offset2, offset1
|
|
if s >= sLimit {
|
|
// Finished
|
|
break encodeLoop
|
|
}
|
|
cv = load6432(src, s)
|
|
}
|
|
}
|
|
|
|
if int(nextEmit) < len(src) {
|
|
blk.literals = append(blk.literals, src[nextEmit:]...)
|
|
blk.extraLits = len(src) - int(nextEmit)
|
|
}
|
|
blk.recentOffsets[0] = uint32(offset1)
|
|
blk.recentOffsets[1] = uint32(offset2)
|
|
if debugEncoder {
|
|
println("returning, recent offsets:", blk.recentOffsets, "extra literals:", blk.extraLits)
|
|
}
|
|
// If we encoded more than 64K mark all dirty.
|
|
if len(src) > 64<<10 {
|
|
e.markAllShardsDirty()
|
|
}
|
|
}
|
|
|
|
// ResetDict will reset and set a dictionary if not nil
|
|
func (e *doubleFastEncoder) Reset(d *dict, singleBlock bool) {
|
|
e.fastEncoder.Reset(d, singleBlock)
|
|
if d != nil {
|
|
panic("doubleFastEncoder: Reset with dict not supported")
|
|
}
|
|
}
|
|
|
|
// ResetDict will reset and set a dictionary if not nil
|
|
func (e *doubleFastEncoderDict) Reset(d *dict, singleBlock bool) {
|
|
allDirty := e.allDirty
|
|
e.fastEncoderDict.Reset(d, singleBlock)
|
|
if d == nil {
|
|
return
|
|
}
|
|
|
|
// Init or copy dict table
|
|
if len(e.dictLongTable) != len(e.longTable) || d.id != e.lastDictID {
|
|
if len(e.dictLongTable) != len(e.longTable) {
|
|
e.dictLongTable = make([]tableEntry, len(e.longTable))
|
|
}
|
|
if len(d.content) >= 8 {
|
|
cv := load6432(d.content, 0)
|
|
e.dictLongTable[hashLen(cv, dFastLongTableBits, dFastLongLen)] = tableEntry{
|
|
val: uint32(cv),
|
|
offset: e.maxMatchOff,
|
|
}
|
|
end := int32(len(d.content)) - 8 + e.maxMatchOff
|
|
for i := e.maxMatchOff + 1; i < end; i++ {
|
|
cv = cv>>8 | (uint64(d.content[i-e.maxMatchOff+7]) << 56)
|
|
e.dictLongTable[hashLen(cv, dFastLongTableBits, dFastLongLen)] = tableEntry{
|
|
val: uint32(cv),
|
|
offset: i,
|
|
}
|
|
}
|
|
}
|
|
e.lastDictID = d.id
|
|
e.allDirty = true
|
|
}
|
|
// Reset table to initial state
|
|
e.cur = e.maxMatchOff
|
|
|
|
dirtyShardCnt := 0
|
|
if !allDirty {
|
|
for i := range e.longTableShardDirty {
|
|
if e.longTableShardDirty[i] {
|
|
dirtyShardCnt++
|
|
}
|
|
}
|
|
}
|
|
|
|
if allDirty || dirtyShardCnt > dLongTableShardCnt/2 {
|
|
copy(e.longTable[:], e.dictLongTable)
|
|
for i := range e.longTableShardDirty {
|
|
e.longTableShardDirty[i] = false
|
|
}
|
|
return
|
|
}
|
|
for i := range e.longTableShardDirty {
|
|
if !e.longTableShardDirty[i] {
|
|
continue
|
|
}
|
|
|
|
copy(e.longTable[i*dLongTableShardSize:(i+1)*dLongTableShardSize], e.dictLongTable[i*dLongTableShardSize:(i+1)*dLongTableShardSize])
|
|
e.longTableShardDirty[i] = false
|
|
}
|
|
}
|
|
|
|
func (e *doubleFastEncoderDict) markLongShardDirty(entryNum uint32) {
|
|
e.longTableShardDirty[entryNum/dLongTableShardSize] = true
|
|
}
|