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* Add Dependencie Update Script * update gitea.com/lunny/levelqueue * update github.com/PuerkitoBio/goquery * update github.com/alecthomas/chroma * update github.com/blevesearch/bleve/v2 * update github.com/caddyserver/certmagic * update github.com/go-enry/go-enry/v2 * update github.com/go-redis/redis/v8 * update github.com/hashicorp/golang-lru * update github.com/klauspost/compress * update github.com/markbates/goth * update github.com/mholt/archiver/v3 * update github.com/microcosm-cc/bluemonday * update github.com/minio/minio-go/v7 * update github.com/olivere/elastic/v7 * update github.com/xanzy/go-gitlab * update github.com/yuin/goldmark
737 lines
19 KiB
Go
Vendored
737 lines
19 KiB
Go
Vendored
// 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 (
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"errors"
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"fmt"
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"io"
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"sync"
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"github.com/klauspost/compress/huff0"
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"github.com/klauspost/compress/zstd/internal/xxhash"
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)
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type blockType uint8
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//go:generate stringer -type=blockType,literalsBlockType,seqCompMode,tableIndex
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const (
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blockTypeRaw blockType = iota
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blockTypeRLE
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blockTypeCompressed
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blockTypeReserved
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)
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type literalsBlockType uint8
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const (
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literalsBlockRaw literalsBlockType = iota
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literalsBlockRLE
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literalsBlockCompressed
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literalsBlockTreeless
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)
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const (
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// maxCompressedBlockSize is the biggest allowed compressed block size (128KB)
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maxCompressedBlockSize = 128 << 10
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// Maximum possible block size (all Raw+Uncompressed).
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maxBlockSize = (1 << 21) - 1
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// https://github.com/facebook/zstd/blob/dev/doc/zstd_compression_format.md#literals_section_header
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maxCompressedLiteralSize = 1 << 18
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maxRLELiteralSize = 1 << 20
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maxMatchLen = 131074
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maxSequences = 0x7f00 + 0xffff
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// We support slightly less than the reference decoder to be able to
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// use ints on 32 bit archs.
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maxOffsetBits = 30
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)
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var (
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huffDecoderPool = sync.Pool{New: func() interface{} {
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return &huff0.Scratch{}
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}}
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fseDecoderPool = sync.Pool{New: func() interface{} {
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return &fseDecoder{}
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}}
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)
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type blockDec struct {
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// Raw source data of the block.
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data []byte
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dataStorage []byte
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// Destination of the decoded data.
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dst []byte
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// Buffer for literals data.
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literalBuf []byte
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// Window size of the block.
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WindowSize uint64
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history chan *history
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input chan struct{}
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result chan decodeOutput
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sequenceBuf []seq
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err error
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decWG sync.WaitGroup
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// Frame to use for singlethreaded decoding.
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// Should not be used by the decoder itself since parent may be another frame.
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localFrame *frameDec
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// Block is RLE, this is the size.
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RLESize uint32
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tmp [4]byte
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Type blockType
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// Is this the last block of a frame?
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Last bool
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// Use less memory
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lowMem bool
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}
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func (b *blockDec) String() string {
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if b == nil {
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return "<nil>"
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}
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return fmt.Sprintf("Steam Size: %d, Type: %v, Last: %t, Window: %d", len(b.data), b.Type, b.Last, b.WindowSize)
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}
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func newBlockDec(lowMem bool) *blockDec {
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b := blockDec{
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lowMem: lowMem,
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result: make(chan decodeOutput, 1),
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input: make(chan struct{}, 1),
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history: make(chan *history, 1),
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}
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b.decWG.Add(1)
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go b.startDecoder()
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return &b
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}
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// reset will reset the block.
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// Input must be a start of a block and will be at the end of the block when returned.
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func (b *blockDec) reset(br byteBuffer, windowSize uint64) error {
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b.WindowSize = windowSize
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tmp, err := br.readSmall(3)
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if err != nil {
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println("Reading block header:", err)
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return err
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}
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bh := uint32(tmp[0]) | (uint32(tmp[1]) << 8) | (uint32(tmp[2]) << 16)
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b.Last = bh&1 != 0
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b.Type = blockType((bh >> 1) & 3)
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// find size.
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cSize := int(bh >> 3)
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maxSize := maxBlockSize
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switch b.Type {
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case blockTypeReserved:
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return ErrReservedBlockType
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case blockTypeRLE:
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b.RLESize = uint32(cSize)
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if b.lowMem {
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maxSize = cSize
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}
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cSize = 1
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case blockTypeCompressed:
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if debugDecoder {
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println("Data size on stream:", cSize)
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}
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b.RLESize = 0
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maxSize = maxCompressedBlockSize
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if windowSize < maxCompressedBlockSize && b.lowMem {
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maxSize = int(windowSize)
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}
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if cSize > maxCompressedBlockSize || uint64(cSize) > b.WindowSize {
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if debugDecoder {
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printf("compressed block too big: csize:%d block: %+v\n", uint64(cSize), b)
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}
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return ErrCompressedSizeTooBig
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}
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case blockTypeRaw:
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b.RLESize = 0
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// We do not need a destination for raw blocks.
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maxSize = -1
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default:
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panic("Invalid block type")
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}
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// Read block data.
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if cap(b.dataStorage) < cSize {
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if b.lowMem || cSize > maxCompressedBlockSize {
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b.dataStorage = make([]byte, 0, cSize)
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} else {
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b.dataStorage = make([]byte, 0, maxCompressedBlockSize)
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}
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}
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if cap(b.dst) <= maxSize {
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b.dst = make([]byte, 0, maxSize+1)
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}
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b.data, err = br.readBig(cSize, b.dataStorage)
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if err != nil {
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if debugDecoder {
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println("Reading block:", err, "(", cSize, ")", len(b.data))
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printf("%T", br)
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}
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return err
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}
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return nil
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}
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// sendEOF will make the decoder send EOF on this frame.
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func (b *blockDec) sendErr(err error) {
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b.Last = true
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b.Type = blockTypeReserved
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b.err = err
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b.input <- struct{}{}
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}
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// Close will release resources.
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// Closed blockDec cannot be reset.
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func (b *blockDec) Close() {
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close(b.input)
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close(b.history)
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close(b.result)
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b.decWG.Wait()
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}
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// decodeAsync will prepare decoding the block when it receives input.
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// This will separate output and history.
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func (b *blockDec) startDecoder() {
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defer b.decWG.Done()
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for range b.input {
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//println("blockDec: Got block input")
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switch b.Type {
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case blockTypeRLE:
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if cap(b.dst) < int(b.RLESize) {
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if b.lowMem {
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b.dst = make([]byte, b.RLESize)
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} else {
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b.dst = make([]byte, maxBlockSize)
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}
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}
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o := decodeOutput{
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d: b,
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b: b.dst[:b.RLESize],
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err: nil,
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}
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v := b.data[0]
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for i := range o.b {
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o.b[i] = v
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}
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hist := <-b.history
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hist.append(o.b)
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b.result <- o
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case blockTypeRaw:
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o := decodeOutput{
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d: b,
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b: b.data,
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err: nil,
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}
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hist := <-b.history
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hist.append(o.b)
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b.result <- o
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case blockTypeCompressed:
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b.dst = b.dst[:0]
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err := b.decodeCompressed(nil)
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o := decodeOutput{
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d: b,
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b: b.dst,
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err: err,
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}
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if debugDecoder {
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println("Decompressed to", len(b.dst), "bytes, error:", err)
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}
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b.result <- o
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case blockTypeReserved:
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// Used for returning errors.
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<-b.history
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b.result <- decodeOutput{
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d: b,
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b: nil,
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err: b.err,
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}
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default:
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panic("Invalid block type")
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}
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if debugDecoder {
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println("blockDec: Finished block")
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}
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}
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}
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// decodeAsync will prepare decoding the block when it receives the history.
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// If history is provided, it will not fetch it from the channel.
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func (b *blockDec) decodeBuf(hist *history) error {
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switch b.Type {
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case blockTypeRLE:
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if cap(b.dst) < int(b.RLESize) {
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if b.lowMem {
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b.dst = make([]byte, b.RLESize)
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} else {
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b.dst = make([]byte, maxBlockSize)
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}
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}
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b.dst = b.dst[:b.RLESize]
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v := b.data[0]
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for i := range b.dst {
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b.dst[i] = v
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}
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hist.appendKeep(b.dst)
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return nil
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case blockTypeRaw:
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hist.appendKeep(b.data)
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return nil
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case blockTypeCompressed:
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saved := b.dst
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b.dst = hist.b
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hist.b = nil
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err := b.decodeCompressed(hist)
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if debugDecoder {
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println("Decompressed to total", len(b.dst), "bytes, hash:", xxhash.Sum64(b.dst), "error:", err)
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}
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hist.b = b.dst
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b.dst = saved
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return err
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case blockTypeReserved:
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// Used for returning errors.
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return b.err
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default:
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panic("Invalid block type")
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}
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}
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// decodeCompressed will start decompressing a block.
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// If no history is supplied the decoder will decodeAsync as much as possible
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// before fetching from blockDec.history
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func (b *blockDec) decodeCompressed(hist *history) error {
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in := b.data
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delayedHistory := hist == nil
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if delayedHistory {
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// We must always grab history.
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defer func() {
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if hist == nil {
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<-b.history
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}
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}()
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}
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// There must be at least one byte for Literals_Block_Type and one for Sequences_Section_Header
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if len(in) < 2 {
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return ErrBlockTooSmall
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}
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litType := literalsBlockType(in[0] & 3)
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var litRegenSize int
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var litCompSize int
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sizeFormat := (in[0] >> 2) & 3
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var fourStreams bool
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switch litType {
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case literalsBlockRaw, literalsBlockRLE:
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switch sizeFormat {
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case 0, 2:
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// Regenerated_Size uses 5 bits (0-31). Literals_Section_Header uses 1 byte.
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litRegenSize = int(in[0] >> 3)
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in = in[1:]
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case 1:
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// Regenerated_Size uses 12 bits (0-4095). Literals_Section_Header uses 2 bytes.
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litRegenSize = int(in[0]>>4) + (int(in[1]) << 4)
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in = in[2:]
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case 3:
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// Regenerated_Size uses 20 bits (0-1048575). Literals_Section_Header uses 3 bytes.
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if len(in) < 3 {
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println("too small: litType:", litType, " sizeFormat", sizeFormat, len(in))
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return ErrBlockTooSmall
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}
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litRegenSize = int(in[0]>>4) + (int(in[1]) << 4) + (int(in[2]) << 12)
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in = in[3:]
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}
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case literalsBlockCompressed, literalsBlockTreeless:
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switch sizeFormat {
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case 0, 1:
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// Both Regenerated_Size and Compressed_Size use 10 bits (0-1023).
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if len(in) < 3 {
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println("too small: litType:", litType, " sizeFormat", sizeFormat, len(in))
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return ErrBlockTooSmall
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}
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n := uint64(in[0]>>4) + (uint64(in[1]) << 4) + (uint64(in[2]) << 12)
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litRegenSize = int(n & 1023)
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litCompSize = int(n >> 10)
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fourStreams = sizeFormat == 1
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in = in[3:]
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case 2:
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fourStreams = true
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if len(in) < 4 {
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println("too small: litType:", litType, " sizeFormat", sizeFormat, len(in))
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return ErrBlockTooSmall
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}
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n := uint64(in[0]>>4) + (uint64(in[1]) << 4) + (uint64(in[2]) << 12) + (uint64(in[3]) << 20)
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litRegenSize = int(n & 16383)
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litCompSize = int(n >> 14)
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in = in[4:]
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case 3:
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fourStreams = true
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if len(in) < 5 {
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println("too small: litType:", litType, " sizeFormat", sizeFormat, len(in))
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return ErrBlockTooSmall
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}
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n := uint64(in[0]>>4) + (uint64(in[1]) << 4) + (uint64(in[2]) << 12) + (uint64(in[3]) << 20) + (uint64(in[4]) << 28)
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litRegenSize = int(n & 262143)
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litCompSize = int(n >> 18)
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in = in[5:]
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}
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}
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if debugDecoder {
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println("literals type:", litType, "litRegenSize:", litRegenSize, "litCompSize:", litCompSize, "sizeFormat:", sizeFormat, "4X:", fourStreams)
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}
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var literals []byte
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var huff *huff0.Scratch
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switch litType {
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case literalsBlockRaw:
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if len(in) < litRegenSize {
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println("too small: litType:", litType, " sizeFormat", sizeFormat, "remain:", len(in), "want:", litRegenSize)
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return ErrBlockTooSmall
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}
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literals = in[:litRegenSize]
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in = in[litRegenSize:]
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//printf("Found %d uncompressed literals\n", litRegenSize)
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case literalsBlockRLE:
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if len(in) < 1 {
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println("too small: litType:", litType, " sizeFormat", sizeFormat, "remain:", len(in), "want:", 1)
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return ErrBlockTooSmall
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}
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if cap(b.literalBuf) < litRegenSize {
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if b.lowMem {
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b.literalBuf = make([]byte, litRegenSize)
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} else {
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if litRegenSize > maxCompressedLiteralSize {
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// Exceptional
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b.literalBuf = make([]byte, litRegenSize)
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} else {
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b.literalBuf = make([]byte, litRegenSize, maxCompressedLiteralSize)
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}
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}
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}
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literals = b.literalBuf[:litRegenSize]
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v := in[0]
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for i := range literals {
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literals[i] = v
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}
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in = in[1:]
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if debugDecoder {
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printf("Found %d RLE compressed literals\n", litRegenSize)
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}
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case literalsBlockTreeless:
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if len(in) < litCompSize {
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println("too small: litType:", litType, " sizeFormat", sizeFormat, "remain:", len(in), "want:", litCompSize)
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return ErrBlockTooSmall
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}
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// Store compressed literals, so we defer decoding until we get history.
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literals = in[:litCompSize]
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in = in[litCompSize:]
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if debugDecoder {
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printf("Found %d compressed literals\n", litCompSize)
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}
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case literalsBlockCompressed:
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if len(in) < litCompSize {
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println("too small: litType:", litType, " sizeFormat", sizeFormat, "remain:", len(in), "want:", litCompSize)
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return ErrBlockTooSmall
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}
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literals = in[:litCompSize]
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in = in[litCompSize:]
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huff = huffDecoderPool.Get().(*huff0.Scratch)
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var err error
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// Ensure we have space to store it.
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if cap(b.literalBuf) < litRegenSize {
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if b.lowMem {
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b.literalBuf = make([]byte, 0, litRegenSize)
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} else {
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b.literalBuf = make([]byte, 0, maxCompressedLiteralSize)
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}
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}
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if huff == nil {
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huff = &huff0.Scratch{}
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}
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huff, literals, err = huff0.ReadTable(literals, huff)
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if err != nil {
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println("reading huffman table:", err)
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return err
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}
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// Use our out buffer.
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if fourStreams {
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literals, err = huff.Decoder().Decompress4X(b.literalBuf[:0:litRegenSize], literals)
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} else {
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literals, err = huff.Decoder().Decompress1X(b.literalBuf[:0:litRegenSize], literals)
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}
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if err != nil {
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println("decoding compressed literals:", err)
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return err
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}
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// Make sure we don't leak our literals buffer
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if len(literals) != litRegenSize {
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return fmt.Errorf("literal output size mismatch want %d, got %d", litRegenSize, len(literals))
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}
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if debugDecoder {
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printf("Decompressed %d literals into %d bytes\n", litCompSize, litRegenSize)
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}
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}
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// Decode Sequences
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// https://github.com/facebook/zstd/blob/dev/doc/zstd_compression_format.md#sequences-section
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if len(in) < 1 {
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return ErrBlockTooSmall
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}
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seqHeader := in[0]
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nSeqs := 0
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switch {
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case seqHeader == 0:
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in = in[1:]
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case seqHeader < 128:
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nSeqs = int(seqHeader)
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in = in[1:]
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case seqHeader < 255:
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if len(in) < 2 {
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return ErrBlockTooSmall
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}
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nSeqs = int(seqHeader-128)<<8 | int(in[1])
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in = in[2:]
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case seqHeader == 255:
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if len(in) < 3 {
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return ErrBlockTooSmall
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}
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nSeqs = 0x7f00 + int(in[1]) + (int(in[2]) << 8)
|
|
in = in[3:]
|
|
}
|
|
// Allocate sequences
|
|
if cap(b.sequenceBuf) < nSeqs {
|
|
if b.lowMem {
|
|
b.sequenceBuf = make([]seq, nSeqs)
|
|
} else {
|
|
// Allocate max
|
|
b.sequenceBuf = make([]seq, nSeqs, maxSequences)
|
|
}
|
|
} else {
|
|
// Reuse buffer
|
|
b.sequenceBuf = b.sequenceBuf[:nSeqs]
|
|
}
|
|
var seqs = &sequenceDecs{}
|
|
if nSeqs > 0 {
|
|
if len(in) < 1 {
|
|
return ErrBlockTooSmall
|
|
}
|
|
br := byteReader{b: in, off: 0}
|
|
compMode := br.Uint8()
|
|
br.advance(1)
|
|
if debugDecoder {
|
|
printf("Compression modes: 0b%b", compMode)
|
|
}
|
|
for i := uint(0); i < 3; i++ {
|
|
mode := seqCompMode((compMode >> (6 - i*2)) & 3)
|
|
if debugDecoder {
|
|
println("Table", tableIndex(i), "is", mode)
|
|
}
|
|
var seq *sequenceDec
|
|
switch tableIndex(i) {
|
|
case tableLiteralLengths:
|
|
seq = &seqs.litLengths
|
|
case tableOffsets:
|
|
seq = &seqs.offsets
|
|
case tableMatchLengths:
|
|
seq = &seqs.matchLengths
|
|
default:
|
|
panic("unknown table")
|
|
}
|
|
switch mode {
|
|
case compModePredefined:
|
|
seq.fse = &fsePredef[i]
|
|
case compModeRLE:
|
|
if br.remain() < 1 {
|
|
return ErrBlockTooSmall
|
|
}
|
|
v := br.Uint8()
|
|
br.advance(1)
|
|
dec := fseDecoderPool.Get().(*fseDecoder)
|
|
symb, err := decSymbolValue(v, symbolTableX[i])
|
|
if err != nil {
|
|
printf("RLE Transform table (%v) error: %v", tableIndex(i), err)
|
|
return err
|
|
}
|
|
dec.setRLE(symb)
|
|
seq.fse = dec
|
|
if debugDecoder {
|
|
printf("RLE set to %+v, code: %v", symb, v)
|
|
}
|
|
case compModeFSE:
|
|
println("Reading table for", tableIndex(i))
|
|
dec := fseDecoderPool.Get().(*fseDecoder)
|
|
err := dec.readNCount(&br, uint16(maxTableSymbol[i]))
|
|
if err != nil {
|
|
println("Read table error:", err)
|
|
return err
|
|
}
|
|
err = dec.transform(symbolTableX[i])
|
|
if err != nil {
|
|
println("Transform table error:", err)
|
|
return err
|
|
}
|
|
if debugDecoder {
|
|
println("Read table ok", "symbolLen:", dec.symbolLen)
|
|
}
|
|
seq.fse = dec
|
|
case compModeRepeat:
|
|
seq.repeat = true
|
|
}
|
|
if br.overread() {
|
|
return io.ErrUnexpectedEOF
|
|
}
|
|
}
|
|
in = br.unread()
|
|
}
|
|
|
|
// Wait for history.
|
|
// All time spent after this is critical since it is strictly sequential.
|
|
if hist == nil {
|
|
hist = <-b.history
|
|
if hist.error {
|
|
return ErrDecoderClosed
|
|
}
|
|
}
|
|
|
|
// Decode treeless literal block.
|
|
if litType == literalsBlockTreeless {
|
|
// TODO: We could send the history early WITHOUT the stream history.
|
|
// This would allow decoding treeless literals before the byte history is available.
|
|
// Silencia stats: Treeless 4393, with: 32775, total: 37168, 11% treeless.
|
|
// So not much obvious gain here.
|
|
|
|
if hist.huffTree == nil {
|
|
return errors.New("literal block was treeless, but no history was defined")
|
|
}
|
|
// Ensure we have space to store it.
|
|
if cap(b.literalBuf) < litRegenSize {
|
|
if b.lowMem {
|
|
b.literalBuf = make([]byte, 0, litRegenSize)
|
|
} else {
|
|
b.literalBuf = make([]byte, 0, maxCompressedLiteralSize)
|
|
}
|
|
}
|
|
var err error
|
|
// Use our out buffer.
|
|
huff = hist.huffTree
|
|
if fourStreams {
|
|
literals, err = huff.Decoder().Decompress4X(b.literalBuf[:0:litRegenSize], literals)
|
|
} else {
|
|
literals, err = huff.Decoder().Decompress1X(b.literalBuf[:0:litRegenSize], literals)
|
|
}
|
|
// Make sure we don't leak our literals buffer
|
|
if err != nil {
|
|
println("decompressing literals:", err)
|
|
return err
|
|
}
|
|
if len(literals) != litRegenSize {
|
|
return fmt.Errorf("literal output size mismatch want %d, got %d", litRegenSize, len(literals))
|
|
}
|
|
} else {
|
|
if hist.huffTree != nil && huff != nil {
|
|
if hist.dict == nil || hist.dict.litEnc != hist.huffTree {
|
|
huffDecoderPool.Put(hist.huffTree)
|
|
}
|
|
hist.huffTree = nil
|
|
}
|
|
}
|
|
if huff != nil {
|
|
hist.huffTree = huff
|
|
}
|
|
if debugDecoder {
|
|
println("Final literals:", len(literals), "hash:", xxhash.Sum64(literals), "and", nSeqs, "sequences.")
|
|
}
|
|
|
|
if nSeqs == 0 {
|
|
// Decompressed content is defined entirely as Literals Section content.
|
|
b.dst = append(b.dst, literals...)
|
|
if delayedHistory {
|
|
hist.append(literals)
|
|
}
|
|
return nil
|
|
}
|
|
|
|
seqs, err := seqs.mergeHistory(&hist.decoders)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
if debugDecoder {
|
|
println("History merged ok")
|
|
}
|
|
br := &bitReader{}
|
|
if err := br.init(in); err != nil {
|
|
return err
|
|
}
|
|
|
|
// TODO: Investigate if sending history without decoders are faster.
|
|
// This would allow the sequences to be decoded async and only have to construct stream history.
|
|
// If only recent offsets were not transferred, this would be an obvious win.
|
|
// Also, if first 3 sequences don't reference recent offsets, all sequences can be decoded.
|
|
|
|
hbytes := hist.b
|
|
if len(hbytes) > hist.windowSize {
|
|
hbytes = hbytes[len(hbytes)-hist.windowSize:]
|
|
// We do not need history any more.
|
|
if hist.dict != nil {
|
|
hist.dict.content = nil
|
|
}
|
|
}
|
|
|
|
if err := seqs.initialize(br, hist, literals, b.dst); err != nil {
|
|
println("initializing sequences:", err)
|
|
return err
|
|
}
|
|
|
|
err = seqs.decode(nSeqs, br, hbytes)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
if !br.finished() {
|
|
return fmt.Errorf("%d extra bits on block, should be 0", br.remain())
|
|
}
|
|
|
|
err = br.close()
|
|
if err != nil {
|
|
printf("Closing sequences: %v, %+v\n", err, *br)
|
|
}
|
|
if len(b.data) > maxCompressedBlockSize {
|
|
return fmt.Errorf("compressed block size too large (%d)", len(b.data))
|
|
}
|
|
// Set output and release references.
|
|
b.dst = seqs.out
|
|
seqs.out, seqs.literals, seqs.hist = nil, nil, nil
|
|
|
|
if !delayedHistory {
|
|
// If we don't have delayed history, no need to update.
|
|
hist.recentOffsets = seqs.prevOffset
|
|
return nil
|
|
}
|
|
if b.Last {
|
|
// if last block we don't care about history.
|
|
println("Last block, no history returned")
|
|
hist.b = hist.b[:0]
|
|
return nil
|
|
}
|
|
hist.append(b.dst)
|
|
hist.recentOffsets = seqs.prevOffset
|
|
if debugDecoder {
|
|
println("Finished block with literals:", len(literals), "and", nSeqs, "sequences.")
|
|
}
|
|
|
|
return nil
|
|
}
|