chore: migrate to gitea

vendor/github.com/ugorji/go/codec/cbor.go

@@ -0,0 +1,995 @@
+//go:build notmono || codec.notmono
+
+// Copyright (c) 2012-2020 Ugorji Nwoke. All rights reserved.
+// Use of this source code is governed by a MIT license found in the LICENSE file.
+
+package codec
+
+import (
+	"io"
+	"math"
+	"math/big"
+	"reflect"
+	"time"
+	"unicode/utf8"
+)
+
+// -------------------
+
+type cborEncDriver[T encWriter] struct {
+	noBuiltInTypes
+	encDriverNoState
+	encDriverNoopContainerWriter
+	encDriverContainerNoTrackerT
+
+	h   *CborHandle
+	e   *encoderBase
+	w   T
+	enc encoderI
+
+	// scratch buffer for: encode time, numbers, etc
+	//
+	// RFC3339Nano uses 35 chars: 2006-01-02T15:04:05.999999999Z07:00
+	b [40]byte
+}
+
+func (e *cborEncDriver[T]) EncodeNil() {
+	e.w.writen1(cborBdNil)
+}
+
+func (e *cborEncDriver[T]) EncodeBool(b bool) {
+	if b {
+		e.w.writen1(cborBdTrue)
+	} else {
+		e.w.writen1(cborBdFalse)
+	}
+}
+
+func (e *cborEncDriver[T]) EncodeFloat32(f float32) {
+	b := math.Float32bits(f)
+	if e.h.OptimumSize {
+		if h := floatToHalfFloatBits(b); halfFloatToFloatBits(h) == b {
+			e.w.writen1(cborBdFloat16)
+			e.w.writen2(bigen.PutUint16(h))
+			return
+		}
+	}
+	e.w.writen1(cborBdFloat32)
+	e.w.writen4(bigen.PutUint32(b))
+}
+
+func (e *cborEncDriver[T]) EncodeFloat64(f float64) {
+	if e.h.OptimumSize {
+		if f32 := float32(f); float64(f32) == f {
+			e.EncodeFloat32(f32)
+			return
+		}
+	}
+	e.w.writen1(cborBdFloat64)
+	e.w.writen8(bigen.PutUint64(math.Float64bits(f)))
+}
+
+func (e *cborEncDriver[T]) encUint(v uint64, bd byte) {
+	if v <= 0x17 {
+		e.w.writen1(byte(v) + bd)
+	} else if v <= math.MaxUint8 {
+		e.w.writen2(bd+0x18, uint8(v))
+	} else if v <= math.MaxUint16 {
+		e.w.writen1(bd + 0x19)
+		e.w.writen2(bigen.PutUint16(uint16(v)))
+	} else if v <= math.MaxUint32 {
+		e.w.writen1(bd + 0x1a)
+		e.w.writen4(bigen.PutUint32(uint32(v)))
+	} else { // if v <= math.MaxUint64 {
+		e.w.writen1(bd + 0x1b)
+		e.w.writen8(bigen.PutUint64(v))
+	}
+}
+
+func (e *cborEncDriver[T]) EncodeInt(v int64) {
+	if v < 0 {
+		e.encUint(uint64(-1-v), cborBaseNegInt)
+	} else {
+		e.encUint(uint64(v), cborBaseUint)
+	}
+}
+
+func (e *cborEncDriver[T]) EncodeUint(v uint64) {
+	e.encUint(v, cborBaseUint)
+}
+
+func (e *cborEncDriver[T]) encLen(bd byte, length int) {
+	e.encUint(uint64(length), bd)
+}
+
+func (e *cborEncDriver[T]) EncodeTime(t time.Time) {
+	if t.IsZero() {
+		e.EncodeNil()
+	} else if e.h.TimeRFC3339 {
+		e.encUint(0, cborBaseTag)
+		e.encStringBytesS(cborBaseString, stringView(t.AppendFormat(e.b[:0], time.RFC3339Nano)))
+	} else {
+		e.encUint(1, cborBaseTag)
+		t = t.UTC().Round(time.Microsecond)
+		sec, nsec := t.Unix(), uint64(t.Nanosecond())
+		if nsec == 0 {
+			e.EncodeInt(sec)
+		} else {
+			e.EncodeFloat64(float64(sec) + float64(nsec)/1e9)
+		}
+	}
+}
+
+func (e *cborEncDriver[T]) EncodeExt(rv interface{}, basetype reflect.Type, xtag uint64, ext Ext) {
+	e.encUint(uint64(xtag), cborBaseTag)
+	if ext == SelfExt {
+		e.enc.encodeAs(rv, basetype, false)
+	} else if v := ext.ConvertExt(rv); v == nil {
+		e.writeNilBytes()
+	} else {
+		e.enc.encodeI(v)
+	}
+}
+
+func (e *cborEncDriver[T]) EncodeRawExt(re *RawExt) {
+	e.encUint(uint64(re.Tag), cborBaseTag)
+	if re.Data != nil {
+		e.w.writeb(re.Data)
+	} else if re.Value != nil {
+		e.enc.encodeI(re.Value)
+	} else {
+		e.EncodeNil()
+	}
+}
+
+func (e *cborEncDriver[T]) WriteArrayEmpty() {
+	if e.h.IndefiniteLength {
+		e.w.writen2(cborBdIndefiniteArray, cborBdBreak)
+	} else {
+		e.w.writen1(cborBaseArray)
+		// e.encLen(cborBaseArray, 0)
+	}
+}
+
+func (e *cborEncDriver[T]) WriteMapEmpty() {
+	if e.h.IndefiniteLength {
+		e.w.writen2(cborBdIndefiniteMap, cborBdBreak)
+	} else {
+		e.w.writen1(cborBaseMap)
+		// e.encLen(cborBaseMap, 0)
+	}
+}
+
+func (e *cborEncDriver[T]) WriteArrayStart(length int) {
+	if e.h.IndefiniteLength {
+		e.w.writen1(cborBdIndefiniteArray)
+	} else {
+		e.encLen(cborBaseArray, length)
+	}
+}
+
+func (e *cborEncDriver[T]) WriteMapStart(length int) {
+	if e.h.IndefiniteLength {
+		e.w.writen1(cborBdIndefiniteMap)
+	} else {
+		e.encLen(cborBaseMap, length)
+	}
+}
+
+func (e *cborEncDriver[T]) WriteMapEnd() {
+	if e.h.IndefiniteLength {
+		e.w.writen1(cborBdBreak)
+	}
+}
+
+func (e *cborEncDriver[T]) WriteArrayEnd() {
+	if e.h.IndefiniteLength {
+		e.w.writen1(cborBdBreak)
+	}
+}
+
+func (e *cborEncDriver[T]) EncodeString(v string) {
+	bb := cborBaseString
+	if e.h.StringToRaw {
+		bb = cborBaseBytes
+	}
+	e.encStringBytesS(bb, v)
+}
+
+func (e *cborEncDriver[T]) EncodeStringNoEscape4Json(v string) { e.EncodeString(v) }
+
+func (e *cborEncDriver[T]) EncodeStringBytesRaw(v []byte) {
+	e.encStringBytesS(cborBaseBytes, stringView(v))
+}
+
+func (e *cborEncDriver[T]) encStringBytesS(bb byte, v string) {
+	if e.h.IndefiniteLength {
+		if bb == cborBaseBytes {
+			e.w.writen1(cborBdIndefiniteBytes)
+		} else {
+			e.w.writen1(cborBdIndefiniteString)
+		}
+		vlen := uint(len(v))
+		n := max(4, min(vlen/4, 1024))
+		for i := uint(0); i < vlen; {
+			i2 := i + n
+			if i2 >= vlen {
+				i2 = vlen
+			}
+			v2 := v[i:i2]
+			e.encLen(bb, len(v2))
+			e.w.writestr(v2)
+			i = i2
+		}
+		e.w.writen1(cborBdBreak)
+	} else {
+		e.encLen(bb, len(v))
+		e.w.writestr(v)
+	}
+}
+
+func (e *cborEncDriver[T]) EncodeBytes(v []byte) {
+	if v == nil {
+		e.writeNilBytes()
+		return
+	}
+	e.EncodeStringBytesRaw(v)
+}
+
+func (e *cborEncDriver[T]) writeNilOr(v byte) {
+	if !e.h.NilCollectionToZeroLength {
+		v = cborBdNil
+	}
+	e.w.writen1(v)
+}
+
+func (e *cborEncDriver[T]) writeNilArray() {
+	e.writeNilOr(cborBaseArray)
+}
+
+func (e *cborEncDriver[T]) writeNilMap() {
+	e.writeNilOr(cborBaseMap)
+}
+
+func (e *cborEncDriver[T]) writeNilBytes() {
+	e.writeNilOr(cborBaseBytes)
+}
+
+// ----------------------
+
+type cborDecDriver[T decReader] struct {
+	decDriverNoopContainerReader
+	// decDriverNoopNumberHelper
+	noBuiltInTypes
+
+	h   *CborHandle
+	d   *decoderBase
+	r   T
+	dec decoderI
+	bdAndBdread
+	// st bool // skip tags
+	// bytes bool
+}
+
+func (d *cborDecDriver[T]) readNextBd() {
+	d.bd = d.r.readn1()
+	d.bdRead = true
+}
+
+func (d *cborDecDriver[T]) advanceNil() (null bool) {
+	if !d.bdRead {
+		d.readNextBd()
+	}
+	if d.bd == cborBdNil || d.bd == cborBdUndefined {
+		d.bdRead = false
+		return true // null = true
+	}
+	return
+}
+
+func (d *cborDecDriver[T]) TryNil() bool {
+	return d.advanceNil()
+}
+
+// skipTags is called to skip any tags in the stream.
+//
+// Since any value can be tagged, then we should call skipTags
+// before any value is decoded.
+//
+// By definition, skipTags should not be called before
+// checking for break, or nil or undefined.
+func (d *cborDecDriver[T]) skipTags() {
+	for d.bd>>5 == cborMajorTag {
+		d.decUint()
+		d.bd = d.r.readn1()
+	}
+}
+
+func (d *cborDecDriver[T]) ContainerType() (vt valueType) {
+	if !d.bdRead {
+		d.readNextBd()
+	}
+	if d.h.SkipUnexpectedTags {
+		d.skipTags()
+	}
+	if d.bd == cborBdNil {
+		d.bdRead = false // always consume nil after seeing it in container type
+		return valueTypeNil
+	}
+	major := d.bd >> 5
+	if major == cborMajorBytes {
+		return valueTypeBytes
+	} else if major == cborMajorString {
+		return valueTypeString
+	} else if major == cborMajorArray {
+		return valueTypeArray
+	} else if major == cborMajorMap {
+		return valueTypeMap
+	}
+	return valueTypeUnset
+}
+
+func (d *cborDecDriver[T]) CheckBreak() (v bool) {
+	if !d.bdRead {
+		d.readNextBd()
+	}
+	if d.bd == cborBdBreak {
+		d.bdRead = false
+		v = true
+	}
+	return
+}
+
+func (d *cborDecDriver[T]) decUint() (ui uint64) {
+	v := d.bd & 0x1f
+	if v <= 0x17 {
+		ui = uint64(v)
+	} else if v == 0x18 {
+		ui = uint64(d.r.readn1())
+	} else if v == 0x19 {
+		ui = uint64(bigen.Uint16(d.r.readn2()))
+	} else if v == 0x1a {
+		ui = uint64(bigen.Uint32(d.r.readn4()))
+	} else if v == 0x1b {
+		ui = uint64(bigen.Uint64(d.r.readn8()))
+	} else {
+		halt.errorf("invalid descriptor decoding uint: %x/%s (%x)", d.bd, cbordesc(d.bd), v)
+	}
+	return
+}
+
+func (d *cborDecDriver[T]) decLen() int {
+	return int(d.decUint())
+}
+
+func (d *cborDecDriver[T]) decFloat() (f float64, ok bool) {
+	ok = true
+	switch d.bd {
+	case cborBdFloat16:
+		f = float64(math.Float32frombits(halfFloatToFloatBits(bigen.Uint16(d.r.readn2()))))
+	case cborBdFloat32:
+		f = float64(math.Float32frombits(bigen.Uint32(d.r.readn4())))
+	case cborBdFloat64:
+		f = math.Float64frombits(bigen.Uint64(d.r.readn8()))
+	default:
+		if d.bd>>5 == cborMajorTag {
+			// extension tag for bignum/decimal
+			switch d.bd & 0x1f { // tag
+			case 2:
+				f = d.decTagBigIntAsFloat(false)
+			case 3:
+				f = d.decTagBigIntAsFloat(true)
+			case 4:
+				f = d.decTagBigFloatAsFloat(true)
+			case 5:
+				f = d.decTagBigFloatAsFloat(false)
+			default:
+				ok = false
+			}
+		} else {
+			ok = false
+		}
+	}
+	return
+}
+
+func (d *cborDecDriver[T]) decInteger() (ui uint64, neg, ok bool) {
+	ok = true
+	switch d.bd >> 5 {
+	case cborMajorUint:
+		ui = d.decUint()
+	case cborMajorNegInt:
+		ui = d.decUint()
+		neg = true
+	default:
+		ok = false
+	}
+	return
+}
+
+func (d *cborDecDriver[T]) DecodeInt64() (i int64) {
+	if d.advanceNil() {
+		return
+	}
+	if d.h.SkipUnexpectedTags {
+		d.skipTags()
+	}
+	v1, v2, v3 := d.decInteger()
+	i = decNegintPosintFloatNumberHelper{d}.int64(v1, v2, v3, true)
+	d.bdRead = false
+	return
+}
+
+func (d *cborDecDriver[T]) DecodeUint64() (ui uint64) {
+	if d.advanceNil() {
+		return
+	}
+	if d.h.SkipUnexpectedTags {
+		d.skipTags()
+	}
+	ui = decNegintPosintFloatNumberHelper{d}.uint64(d.decInteger())
+	d.bdRead = false
+	return
+}
+
+func (d *cborDecDriver[T]) DecodeFloat64() (f float64) {
+	if d.advanceNil() {
+		return
+	}
+	if d.h.SkipUnexpectedTags {
+		d.skipTags()
+	}
+	v1, v2 := d.decFloat()
+	f = decNegintPosintFloatNumberHelper{d}.float64(v1, v2, true)
+	d.bdRead = false
+	return
+}
+
+// bool can be decoded from bool only (single byte).
+func (d *cborDecDriver[T]) DecodeBool() (b bool) {
+	if d.advanceNil() {
+		return
+	}
+	if d.h.SkipUnexpectedTags {
+		d.skipTags()
+	}
+	if d.bd == cborBdTrue {
+		b = true
+	} else if d.bd == cborBdFalse {
+	} else {
+		halt.errorf("not bool - %s %x/%s", msgBadDesc, d.bd, cbordesc(d.bd))
+	}
+	d.bdRead = false
+	return
+}
+
+func (d *cborDecDriver[T]) ReadMapStart() (length int) {
+	if d.advanceNil() {
+		return containerLenNil
+	}
+	if d.h.SkipUnexpectedTags {
+		d.skipTags()
+	}
+	d.bdRead = false
+	if d.bd == cborBdIndefiniteMap {
+		return containerLenUnknown
+	}
+	if d.bd>>5 != cborMajorMap {
+		halt.errorf("error reading map; got major type: %x, expected %x/%s", d.bd>>5, cborMajorMap, cbordesc(d.bd))
+	}
+	return d.decLen()
+}
+
+func (d *cborDecDriver[T]) ReadArrayStart() (length int) {
+	if d.advanceNil() {
+		return containerLenNil
+	}
+	if d.h.SkipUnexpectedTags {
+		d.skipTags()
+	}
+	d.bdRead = false
+	if d.bd == cborBdIndefiniteArray {
+		return containerLenUnknown
+	}
+	if d.bd>>5 != cborMajorArray {
+		halt.errorf("invalid array; got major type: %x, expect: %x/%s", d.bd>>5, cborMajorArray, cbordesc(d.bd))
+	}
+	return d.decLen()
+}
+
+// MARKER d.d.buf is ONLY used within DecodeBytes.
+// Safe to use freely here only.
+
+func (d *cborDecDriver[T]) DecodeBytes() (bs []byte, state dBytesAttachState) {
+	if d.advanceNil() {
+		return
+	}
+	if d.h.SkipUnexpectedTags {
+		d.skipTags()
+	}
+	fnEnsureNonNilBytes := func() {
+		// buf is nil at first. Ensure a non-nil value is returned.
+		if bs == nil {
+			bs = zeroByteSlice
+			state = dBytesDetach
+		}
+	}
+	if d.bd == cborBdIndefiniteBytes || d.bd == cborBdIndefiniteString {
+		major := d.bd >> 5
+		val4str := d.h.ValidateUnicode && major == cborMajorString
+		bs = d.d.buf[:0]
+		d.bdRead = false
+		for !d.CheckBreak() {
+			if d.bd>>5 != major {
+				const msg = "malformed indefinite string/bytes %x (%s); " +
+					"contains chunk with major type %v, expected %v"
+				halt.errorf(msg, d.bd, cbordesc(d.bd), d.bd>>5, major)
+			}
+			n := uint(d.decLen())
+			bs = append(bs, d.r.readx(n)...)
+			d.bdRead = false
+			if val4str && !utf8.Valid(bs[len(bs)-int(n):]) {
+				const msg = "indefinite-length text string contains chunk " +
+					"that is not a valid utf-8 sequence: 0x%x"
+				halt.errorf(msg, bs[len(bs)-int(n):])
+			}
+		}
+		d.bdRead = false
+		d.d.buf = bs
+		state = dBytesAttachBuffer
+		fnEnsureNonNilBytes()
+		return
+	}
+	if d.bd == cborBdIndefiniteArray {
+		d.bdRead = false
+		bs = d.d.buf[:0]
+		for !d.CheckBreak() {
+			bs = append(bs, uint8(chkOvf.UintV(d.DecodeUint64(), 8)))
+		}
+		d.d.buf = bs
+		state = dBytesAttachBuffer
+		fnEnsureNonNilBytes()
+		return
+	}
+	var cond bool
+	if d.bd>>5 == cborMajorArray {
+		d.bdRead = false
+		slen := d.decLen()
+		bs, cond = usableByteSlice(d.d.buf, slen)
+		for i := 0; i < len(bs); i++ {
+			bs[i] = uint8(chkOvf.UintV(d.DecodeUint64(), 8))
+		}
+		for i := len(bs); i < slen; i++ {
+			bs = append(bs, uint8(chkOvf.UintV(d.DecodeUint64(), 8)))
+		}
+		if cond {
+			d.d.buf = bs
+		}
+		state = dBytesAttachBuffer
+		fnEnsureNonNilBytes()
+		return
+	}
+	clen := d.decLen()
+	d.bdRead = false
+	bs, cond = d.r.readxb(uint(clen))
+	state = d.d.attachState(cond)
+	return
+}
+
+func (d *cborDecDriver[T]) DecodeStringAsBytes() (out []byte, state dBytesAttachState) {
+	out, state = d.DecodeBytes()
+	if d.h.ValidateUnicode && !utf8.Valid(out) {
+		halt.errorf("DecodeStringAsBytes: invalid UTF-8: %s", out)
+	}
+	return
+}
+
+func (d *cborDecDriver[T]) DecodeTime() (t time.Time) {
+	if d.advanceNil() {
+		return
+	}
+	if d.bd>>5 != cborMajorTag {
+		halt.errorf("error reading tag; expected major type: %x, got: %x", cborMajorTag, d.bd>>5)
+	}
+	xtag := d.decUint()
+	d.bdRead = false
+	return d.decodeTime(xtag)
+}
+
+func (d *cborDecDriver[T]) decodeTime(xtag uint64) (t time.Time) {
+	switch xtag {
+	case 0:
+		var err error
+		t, err = time.Parse(time.RFC3339, stringView(bytesOKs(d.DecodeStringAsBytes())))
+		halt.onerror(err)
+	case 1:
+		f1, f2 := math.Modf(d.DecodeFloat64())
+		t = time.Unix(int64(f1), int64(f2*1e9))
+	default:
+		halt.errorf("invalid tag for time.Time - expecting 0 or 1, got 0x%x", xtag)
+	}
+	t = t.UTC().Round(time.Microsecond)
+	return
+}
+
+func (d *cborDecDriver[T]) preDecodeExt(checkTag bool, xtag uint64) (realxtag uint64, ok bool) {
+	if d.advanceNil() {
+		return
+	}
+	if d.bd>>5 != cborMajorTag {
+		halt.errorf("error reading tag; expected major type: %x, got: %x", cborMajorTag, d.bd>>5)
+	}
+	realxtag = d.decUint()
+	d.bdRead = false
+	if checkTag && xtag != realxtag {
+		halt.errorf("Wrong extension tag. Got %b. Expecting: %v", realxtag, xtag)
+	}
+	ok = true
+	return
+}
+
+func (d *cborDecDriver[T]) DecodeRawExt(re *RawExt) {
+	if realxtag, ok := d.preDecodeExt(false, 0); ok {
+		re.Tag = realxtag
+		d.dec.decode(&re.Value)
+		d.bdRead = false
+	}
+}
+
+func (d *cborDecDriver[T]) DecodeExt(rv interface{}, basetype reflect.Type, xtag uint64, ext Ext) {
+	if _, ok := d.preDecodeExt(true, xtag); ok {
+		if ext == SelfExt {
+			d.dec.decodeAs(rv, basetype, false)
+		} else {
+			d.dec.interfaceExtConvertAndDecode(rv, ext)
+		}
+		d.bdRead = false
+	}
+}
+
+func (d *cborDecDriver[T]) decTagBigIntAsFloat(neg bool) (f float64) {
+	bs, _ := d.DecodeBytes()
+	bi := new(big.Int).SetBytes(bs)
+	if neg { // neg big.Int
+		bi0 := bi
+		bi = new(big.Int).Sub(big.NewInt(-1), bi0)
+	}
+	f, _ = bi.Float64()
+	return
+}
+
+func (d *cborDecDriver[T]) decTagBigFloatAsFloat(decimal bool) (f float64) {
+	if nn := d.r.readn1(); nn != 82 {
+		halt.errorf("(%d) decoding decimal/big.Float: expected 2 numbers", nn)
+	}
+	exp := d.DecodeInt64()
+	mant := d.DecodeInt64()
+	if decimal { // m*(10**e)
+		// MARKER: if precision/other issues crop, consider using big.Float on base 10.
+		// The logic is more convoluted, which is why we leverage readFloatResult for now.
+		rf := readFloatResult{exp: int8(exp)}
+		if mant >= 0 {
+			rf.mantissa = uint64(mant)
+		} else {
+			rf.neg = true
+			rf.mantissa = uint64(-mant)
+		}
+		f, _ = parseFloat64_reader(rf)
+		// f = float64(mant) * math.Pow10(exp)
+	} else { // m*(2**e)
+		// f = float64(mant) * math.Pow(2, exp)
+		bfm := new(big.Float).SetPrec(64).SetInt64(mant)
+		bf := new(big.Float).SetPrec(64).SetMantExp(bfm, int(exp))
+		f, _ = bf.Float64()
+	}
+	return
+}
+
+func (d *cborDecDriver[T]) DecodeNaked() {
+	if !d.bdRead {
+		d.readNextBd()
+	}
+
+	n := d.d.naked()
+	var decodeFurther bool
+	switch d.bd >> 5 {
+	case cborMajorUint:
+		if d.h.SignedInteger {
+			n.v = valueTypeInt
+			n.i = d.DecodeInt64()
+		} else {
+			n.v = valueTypeUint
+			n.u = d.DecodeUint64()
+		}
+	case cborMajorNegInt:
+		n.v = valueTypeInt
+		n.i = d.DecodeInt64()
+	case cborMajorBytes:
+		d.d.fauxUnionReadRawBytes(d, false, d.h.RawToString) //, d.h.ZeroCopy)
+	case cborMajorString:
+		n.v = valueTypeString
+		n.s = d.d.detach2Str(d.DecodeStringAsBytes())
+	case cborMajorArray:
+		n.v = valueTypeArray
+		decodeFurther = true
+	case cborMajorMap:
+		n.v = valueTypeMap
+		decodeFurther = true
+	case cborMajorTag:
+		n.v = valueTypeExt
+		n.u = d.decUint()
+		d.bdRead = false
+		n.l = nil
+		xx := d.h.getExtForTag(n.u)
+		if xx == nil {
+			switch n.u {
+			case 0, 1:
+				n.v = valueTypeTime
+				n.t = d.decodeTime(n.u)
+			case 2:
+				n.f = d.decTagBigIntAsFloat(false)
+				n.v = valueTypeFloat
+			case 3:
+				n.f = d.decTagBigIntAsFloat(true)
+				n.v = valueTypeFloat
+			case 4:
+				n.f = d.decTagBigFloatAsFloat(true)
+				n.v = valueTypeFloat
+			case 5:
+				n.f = d.decTagBigFloatAsFloat(false)
+				n.v = valueTypeFloat
+			case 55799: // skip
+				d.DecodeNaked()
+			default:
+				if d.h.SkipUnexpectedTags {
+					d.DecodeNaked()
+				}
+				// else we will use standard mode to decode ext e.g. into a RawExt
+			}
+			return
+		}
+		// if n.u == 0 || n.u == 1 {
+		// 	d.bdRead = false
+		// 	n.v = valueTypeTime
+		// 	n.t = d.decodeTime(n.u)
+		// } else if d.h.SkipUnexpectedTags && d.h.getExtForTag(n.u) == nil {
+		// 	// d.skipTags() // no need to call this - tags already skipped
+		// 	d.bdRead = false
+		// 	d.DecodeNaked()
+		// 	return // return when done (as true recursive function)
+		// }
+	case cborMajorSimpleOrFloat:
+		switch d.bd {
+		case cborBdNil, cborBdUndefined:
+			n.v = valueTypeNil
+		case cborBdFalse:
+			n.v = valueTypeBool
+			n.b = false
+		case cborBdTrue:
+			n.v = valueTypeBool
+			n.b = true
+		case cborBdFloat16, cborBdFloat32, cborBdFloat64:
+			n.v = valueTypeFloat
+			n.f = d.DecodeFloat64()
+		default:
+			halt.errorf("decodeNaked: Unrecognized d.bd: 0x%x", d.bd)
+		}
+	default: // should never happen
+		halt.errorf("decodeNaked: Unrecognized d.bd: 0x%x", d.bd)
+	}
+	if !decodeFurther {
+		d.bdRead = false
+	}
+}
+
+func (d *cborDecDriver[T]) uintBytes() (v []byte, ui uint64) {
+	// this is only used by nextValueBytes, so it's ok to
+	// use readx and bigenstd here.
+	switch vv := d.bd & 0x1f; vv {
+	case 0x18:
+		v = d.r.readx(1)
+		ui = uint64(v[0])
+	case 0x19:
+		v = d.r.readx(2)
+		ui = uint64(bigenstd.Uint16(v))
+	case 0x1a:
+		v = d.r.readx(4)
+		ui = uint64(bigenstd.Uint32(v))
+	case 0x1b:
+		v = d.r.readx(8)
+		ui = uint64(bigenstd.Uint64(v))
+	default:
+		if vv > 0x1b {
+			halt.errorf("invalid descriptor decoding uint: %x/%s", d.bd, cbordesc(d.bd))
+		}
+		ui = uint64(vv)
+	}
+	return
+}
+
+func (d *cborDecDriver[T]) nextValueBytes() (v []byte) {
+	if !d.bdRead {
+		d.readNextBd()
+	}
+	d.r.startRecording()
+	d.nextValueBytesBdReadR()
+	v = d.r.stopRecording()
+	d.bdRead = false
+	return
+}
+
+// func (d *cborDecDriver[T]) nextValueBytesR(v0 []byte) (v []byte) {
+// 	d.readNextBd()
+// 	v0 = append(v0, d.bd)
+// 	d.r.startRecording(v0)
+// 	d.nextValueBytesBdReadR()
+// 	v = d.r.stopRecording()
+// 	return
+// }
+
+func (d *cborDecDriver[T]) nextValueBytesBdReadR() {
+	// var bs []byte
+	var ui uint64
+
+	switch d.bd >> 5 {
+	case cborMajorUint, cborMajorNegInt:
+		d.uintBytes()
+	case cborMajorString, cborMajorBytes:
+		if d.bd == cborBdIndefiniteBytes || d.bd == cborBdIndefiniteString {
+			for {
+				d.readNextBd()
+				if d.bd == cborBdBreak {
+					break
+				}
+				_, ui = d.uintBytes()
+				d.r.skip(uint(ui))
+			}
+		} else {
+			_, ui = d.uintBytes()
+			d.r.skip(uint(ui))
+		}
+	case cborMajorArray:
+		if d.bd == cborBdIndefiniteArray {
+			for {
+				d.readNextBd()
+				if d.bd == cborBdBreak {
+					break
+				}
+				d.nextValueBytesBdReadR()
+			}
+		} else {
+			_, ui = d.uintBytes()
+			for i := uint64(0); i < ui; i++ {
+				d.readNextBd()
+				d.nextValueBytesBdReadR()
+			}
+		}
+	case cborMajorMap:
+		if d.bd == cborBdIndefiniteMap {
+			for {
+				d.readNextBd()
+				if d.bd == cborBdBreak {
+					break
+				}
+				d.nextValueBytesBdReadR()
+				d.readNextBd()
+				d.nextValueBytesBdReadR()
+			}
+		} else {
+			_, ui = d.uintBytes()
+			for i := uint64(0); i < ui; i++ {
+				d.readNextBd()
+				d.nextValueBytesBdReadR()
+				d.readNextBd()
+				d.nextValueBytesBdReadR()
+			}
+		}
+	case cborMajorTag:
+		d.uintBytes()
+		d.readNextBd()
+		d.nextValueBytesBdReadR()
+	case cborMajorSimpleOrFloat:
+		switch d.bd {
+		case cborBdNil, cborBdUndefined, cborBdFalse, cborBdTrue: // pass
+		case cborBdFloat16:
+			d.r.skip(2)
+		case cborBdFloat32:
+			d.r.skip(4)
+		case cborBdFloat64:
+			d.r.skip(8)
+		default:
+			halt.errorf("nextValueBytes: Unrecognized d.bd: 0x%x", d.bd)
+		}
+	default: // should never happen
+		halt.errorf("nextValueBytes: Unrecognized d.bd: 0x%x", d.bd)
+	}
+	return
+}
+
+func (d *cborDecDriver[T]) reset() {
+	d.bdAndBdread.reset()
+	// d.st = d.h.SkipUnexpectedTags
+}
+
+// ----
+//
+// The following below are similar across all format files (except for the format name).
+//
+// We keep them together here, so that we can easily copy and compare.
+
+// ----
+
+func (d *cborEncDriver[T]) init(hh Handle, shared *encoderBase, enc encoderI) (fp interface{}) {
+	callMake(&d.w)
+	d.h = hh.(*CborHandle)
+	d.e = shared
+	if shared.bytes {
+		fp = cborFpEncBytes
+	} else {
+		fp = cborFpEncIO
+	}
+	// d.w.init()
+	d.init2(enc)
+	return
+}
+
+func (e *cborEncDriver[T]) writeBytesAsis(b []byte) { e.w.writeb(b) }
+
+// func (e *cborEncDriver[T]) writeStringAsisDblQuoted(v string) { e.w.writeqstr(v) }
+
+func (e *cborEncDriver[T]) writerEnd() { e.w.end() }
+
+func (e *cborEncDriver[T]) resetOutBytes(out *[]byte) {
+	e.w.resetBytes(*out, out)
+}
+
+func (e *cborEncDriver[T]) resetOutIO(out io.Writer) {
+	e.w.resetIO(out, e.h.WriterBufferSize, &e.e.blist)
+}
+
+// ----
+
+func (d *cborDecDriver[T]) init(hh Handle, shared *decoderBase, dec decoderI) (fp interface{}) {
+	callMake(&d.r)
+	d.h = hh.(*CborHandle)
+	d.d = shared
+	if shared.bytes {
+		fp = cborFpDecBytes
+	} else {
+		fp = cborFpDecIO
+	}
+	// d.r.init()
+	d.init2(dec)
+	return
+}
+
+func (d *cborDecDriver[T]) NumBytesRead() int {
+	return int(d.r.numread())
+}
+
+func (d *cborDecDriver[T]) resetInBytes(in []byte) {
+	d.r.resetBytes(in)
+}
+
+func (d *cborDecDriver[T]) resetInIO(r io.Reader) {
+	d.r.resetIO(r, d.h.ReaderBufferSize, d.h.MaxInitLen, &d.d.blist)
+}
+
+// ---- (custom stanza)
+
+func (d *cborDecDriver[T]) descBd() string {
+	return sprintf("%v (%s)", d.bd, cbordesc(d.bd))
+}
+
+func (d *cborDecDriver[T]) DecodeFloat32() (f float32) {
+	return float32(chkOvf.Float32V(d.DecodeFloat64()))
+}
+
+func (d *cborEncDriver[T]) init2(enc encoderI) {
+	d.enc = enc
+}
+
+func (d *cborDecDriver[T]) init2(dec decoderI) {
+	d.dec = dec
+	// d.d.cbor = true
+}