Method resetBase

zstd/enc_base.go:160–199

Reset the encoding table.

(d *dict, singleBlock bool)

// Reset the encoding table.
func (e *fastBase) resetBase(d *dict, singleBlock bool) {
	if e.blk == nil {
		e.blk = &blockEnc{lowMem: e.lowMem}
		e.blk.init()
	} else {
		e.blk.reset(nil)
	}
	e.blk.initNewEncode()
	if e.crc == nil {
		e.crc = xxhash.New()
	} else {
		e.crc.Reset()
	}
	e.blk.dictLitEnc = nil
	if d != nil {
		low := e.lowMem
		if singleBlock {
			e.lowMem = true
		}
		e.ensureHist(d.ContentSize() + maxCompressedBlockSize)
		e.lowMem = low
	}

	// We offset current position so everything will be out of reach.
	// If above reset line, history will be purged.
	if e.cur < e.bufferReset {
		e.cur += e.maxMatchOff + int32(len(e.hist))
	}
	e.hist = e.hist[:0]
	if d != nil {
		// Set offsets (currently not used)
		for i, off := range d.offsets {
			e.blk.recentOffsets[i] = uint32(off)
			e.blk.prevRecentOffsets[i] = e.blk.recentOffsets[i]
		}
		// Transfer litenc.
		e.blk.dictLitEnc = d.litEnc
		e.hist = append(e.hist, d.content...)
	}
}