Check in the vendor directory

Travis seems to be having issues pulling deps, so we'll have to check in
the vendor directory and prevent the makefile from trying to regenerate
it normally.

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

@@ -0,0 +1,756 @@
+// Copyright (c) 2012-2018 Ugorji Nwoke. All rights reserved.
+// Use of this source code is governed by a MIT license found in the LICENSE file.
+
+package codec
+
+import (
+	"math"
+	"reflect"
+	"time"
+)
+
+const (
+	cborMajorUint byte = iota
+	cborMajorNegInt
+	cborMajorBytes
+	cborMajorText
+	cborMajorArray
+	cborMajorMap
+	cborMajorTag
+	cborMajorOther
+)
+
+const (
+	cborBdFalse byte = 0xf4 + iota
+	cborBdTrue
+	cborBdNil
+	cborBdUndefined
+	cborBdExt
+	cborBdFloat16
+	cborBdFloat32
+	cborBdFloat64
+)
+
+const (
+	cborBdIndefiniteBytes  byte = 0x5f
+	cborBdIndefiniteString      = 0x7f
+	cborBdIndefiniteArray       = 0x9f
+	cborBdIndefiniteMap         = 0xbf
+	cborBdBreak                 = 0xff
+)
+
+// These define some in-stream descriptors for
+// manual encoding e.g. when doing explicit indefinite-length
+const (
+	CborStreamBytes  byte = 0x5f
+	CborStreamString      = 0x7f
+	CborStreamArray       = 0x9f
+	CborStreamMap         = 0xbf
+	CborStreamBreak       = 0xff
+)
+
+const (
+	cborBaseUint   byte = 0x00
+	cborBaseNegInt      = 0x20
+	cborBaseBytes       = 0x40
+	cborBaseString      = 0x60
+	cborBaseArray       = 0x80
+	cborBaseMap         = 0xa0
+	cborBaseTag         = 0xc0
+	cborBaseSimple      = 0xe0
+)
+
+func cbordesc(bd byte) string {
+	switch bd {
+	case cborBdNil:
+		return "nil"
+	case cborBdFalse:
+		return "false"
+	case cborBdTrue:
+		return "true"
+	case cborBdFloat16, cborBdFloat32, cborBdFloat64:
+		return "float"
+	case cborBdIndefiniteBytes:
+		return "bytes*"
+	case cborBdIndefiniteString:
+		return "string*"
+	case cborBdIndefiniteArray:
+		return "array*"
+	case cborBdIndefiniteMap:
+		return "map*"
+	default:
+		switch {
+		case bd >= cborBaseUint && bd < cborBaseNegInt:
+			return "(u)int"
+		case bd >= cborBaseNegInt && bd < cborBaseBytes:
+			return "int"
+		case bd >= cborBaseBytes && bd < cborBaseString:
+			return "bytes"
+		case bd >= cborBaseString && bd < cborBaseArray:
+			return "string"
+		case bd >= cborBaseArray && bd < cborBaseMap:
+			return "array"
+		case bd >= cborBaseMap && bd < cborBaseTag:
+			return "map"
+		case bd >= cborBaseTag && bd < cborBaseSimple:
+			return "ext"
+		default:
+			return "unknown"
+		}
+	}
+}
+
+// -------------------
+
+type cborEncDriver struct {
+	noBuiltInTypes
+	encDriverNoopContainerWriter
+	// encNoSeparator
+	e *Encoder
+	w encWriter
+	h *CborHandle
+	x [8]byte
+	_ [3]uint64 // padding
+}
+
+func (e *cborEncDriver) EncodeNil() {
+	e.w.writen1(cborBdNil)
+}
+
+func (e *cborEncDriver) EncodeBool(b bool) {
+	if b {
+		e.w.writen1(cborBdTrue)
+	} else {
+		e.w.writen1(cborBdFalse)
+	}
+}
+
+func (e *cborEncDriver) EncodeFloat32(f float32) {
+	e.w.writen1(cborBdFloat32)
+	bigenHelper{e.x[:4], e.w}.writeUint32(math.Float32bits(f))
+}
+
+func (e *cborEncDriver) EncodeFloat64(f float64) {
+	e.w.writen1(cborBdFloat64)
+	bigenHelper{e.x[:8], e.w}.writeUint64(math.Float64bits(f))
+}
+
+func (e *cborEncDriver) 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)
+		bigenHelper{e.x[:2], e.w}.writeUint16(uint16(v))
+	} else if v <= math.MaxUint32 {
+		e.w.writen1(bd + 0x1a)
+		bigenHelper{e.x[:4], e.w}.writeUint32(uint32(v))
+	} else { // if v <= math.MaxUint64 {
+		e.w.writen1(bd + 0x1b)
+		bigenHelper{e.x[:8], e.w}.writeUint64(v)
+	}
+}
+
+func (e *cborEncDriver) EncodeInt(v int64) {
+	if v < 0 {
+		e.encUint(uint64(-1-v), cborBaseNegInt)
+	} else {
+		e.encUint(uint64(v), cborBaseUint)
+	}
+}
+
+func (e *cborEncDriver) EncodeUint(v uint64) {
+	e.encUint(v, cborBaseUint)
+}
+
+func (e *cborEncDriver) encLen(bd byte, length int) {
+	e.encUint(uint64(length), bd)
+}
+
+func (e *cborEncDriver) EncodeTime(t time.Time) {
+	if t.IsZero() {
+		e.EncodeNil()
+	} else if e.h.TimeRFC3339 {
+		e.encUint(0, cborBaseTag)
+		e.EncodeString(cUTF8, t.Format(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) EncodeExt(rv interface{}, xtag uint64, ext Ext, en *Encoder) {
+	e.encUint(uint64(xtag), cborBaseTag)
+	if v := ext.ConvertExt(rv); v == nil {
+		e.EncodeNil()
+	} else {
+		en.encode(v)
+	}
+}
+
+func (e *cborEncDriver) EncodeRawExt(re *RawExt, en *Encoder) {
+	e.encUint(uint64(re.Tag), cborBaseTag)
+	if false && re.Data != nil {
+		en.encode(re.Data)
+	} else if re.Value != nil {
+		en.encode(re.Value)
+	} else {
+		e.EncodeNil()
+	}
+}
+
+func (e *cborEncDriver) WriteArrayStart(length int) {
+	if e.h.IndefiniteLength {
+		e.w.writen1(cborBdIndefiniteArray)
+	} else {
+		e.encLen(cborBaseArray, length)
+	}
+}
+
+func (e *cborEncDriver) WriteMapStart(length int) {
+	if e.h.IndefiniteLength {
+		e.w.writen1(cborBdIndefiniteMap)
+	} else {
+		e.encLen(cborBaseMap, length)
+	}
+}
+
+func (e *cborEncDriver) WriteMapEnd() {
+	if e.h.IndefiniteLength {
+		e.w.writen1(cborBdBreak)
+	}
+}
+
+func (e *cborEncDriver) WriteArrayEnd() {
+	if e.h.IndefiniteLength {
+		e.w.writen1(cborBdBreak)
+	}
+}
+
+func (e *cborEncDriver) EncodeString(c charEncoding, v string) {
+	e.encStringBytesS(cborBaseString, v)
+}
+
+func (e *cborEncDriver) EncodeStringBytes(c charEncoding, v []byte) {
+	if v == nil {
+		e.EncodeNil()
+	} else if c == cRAW {
+		e.encStringBytesS(cborBaseBytes, stringView(v))
+	} else {
+		e.encStringBytesS(cborBaseString, stringView(v))
+	}
+}
+
+func (e *cborEncDriver) encStringBytesS(bb byte, v string) {
+	if e.h.IndefiniteLength {
+		if bb == cborBaseBytes {
+			e.w.writen1(cborBdIndefiniteBytes)
+		} else {
+			e.w.writen1(cborBdIndefiniteString)
+		}
+		blen := len(v) / 4
+		if blen == 0 {
+			blen = 64
+		} else if blen > 1024 {
+			blen = 1024
+		}
+		for i := 0; i < len(v); {
+			var v2 string
+			i2 := i + blen
+			if i2 < len(v) {
+				v2 = v[i:i2]
+			} else {
+				v2 = v[i:]
+			}
+			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)
+	}
+}
+
+// ----------------------
+
+type cborDecDriver struct {
+	d *Decoder
+	h *CborHandle
+	r decReader
+	// b      [scratchByteArrayLen]byte
+	br     bool // bytes reader
+	bdRead bool
+	bd     byte
+	noBuiltInTypes
+	// decNoSeparator
+	decDriverNoopContainerReader
+	_ [3]uint64 // padding
+}
+
+func (d *cborDecDriver) readNextBd() {
+	d.bd = d.r.readn1()
+	d.bdRead = true
+}
+
+func (d *cborDecDriver) uncacheRead() {
+	if d.bdRead {
+		d.r.unreadn1()
+		d.bdRead = false
+	}
+}
+
+func (d *cborDecDriver) ContainerType() (vt valueType) {
+	if !d.bdRead {
+		d.readNextBd()
+	}
+	if d.bd == cborBdNil {
+		return valueTypeNil
+	} else if d.bd == cborBdIndefiniteBytes || (d.bd >= cborBaseBytes && d.bd < cborBaseString) {
+		return valueTypeBytes
+	} else if d.bd == cborBdIndefiniteString || (d.bd >= cborBaseString && d.bd < cborBaseArray) {
+		return valueTypeString
+	} else if d.bd == cborBdIndefiniteArray || (d.bd >= cborBaseArray && d.bd < cborBaseMap) {
+		return valueTypeArray
+	} else if d.bd == cborBdIndefiniteMap || (d.bd >= cborBaseMap && d.bd < cborBaseTag) {
+		return valueTypeMap
+	}
+	// else {
+	// d.d.errorf("isContainerType: unsupported parameter: %v", vt)
+	// }
+	return valueTypeUnset
+}
+
+func (d *cborDecDriver) TryDecodeAsNil() bool {
+	if !d.bdRead {
+		d.readNextBd()
+	}
+	// treat Nil and Undefined as nil values
+	if d.bd == cborBdNil || d.bd == cborBdUndefined {
+		d.bdRead = false
+		return true
+	}
+	return false
+}
+
+func (d *cborDecDriver) CheckBreak() bool {
+	if !d.bdRead {
+		d.readNextBd()
+	}
+	if d.bd == cborBdBreak {
+		d.bdRead = false
+		return true
+	}
+	return false
+}
+
+func (d *cborDecDriver) 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.readx(2)))
+		} else if v == 0x1a {
+			ui = uint64(bigen.Uint32(d.r.readx(4)))
+		} else if v == 0x1b {
+			ui = uint64(bigen.Uint64(d.r.readx(8)))
+		} else {
+			d.d.errorf("invalid descriptor decoding uint: %x/%s", d.bd, cbordesc(d.bd))
+			return
+		}
+	}
+	return
+}
+
+func (d *cborDecDriver) decCheckInteger() (neg bool) {
+	if !d.bdRead {
+		d.readNextBd()
+	}
+	major := d.bd >> 5
+	if major == cborMajorUint {
+	} else if major == cborMajorNegInt {
+		neg = true
+	} else {
+		d.d.errorf("not an integer - invalid major %v from descriptor %x/%s", major, d.bd, cbordesc(d.bd))
+		return
+	}
+	return
+}
+
+func (d *cborDecDriver) DecodeInt64() (i int64) {
+	neg := d.decCheckInteger()
+	ui := d.decUint()
+	// check if this number can be converted to an int without overflow
+	if neg {
+		i = -(chkOvf.SignedIntV(ui + 1))
+	} else {
+		i = chkOvf.SignedIntV(ui)
+	}
+	d.bdRead = false
+	return
+}
+
+func (d *cborDecDriver) DecodeUint64() (ui uint64) {
+	if d.decCheckInteger() {
+		d.d.errorf("assigning negative signed value to unsigned type")
+		return
+	}
+	ui = d.decUint()
+	d.bdRead = false
+	return
+}
+
+func (d *cborDecDriver) DecodeFloat64() (f float64) {
+	if !d.bdRead {
+		d.readNextBd()
+	}
+	if bd := d.bd; bd == cborBdFloat16 {
+		f = float64(math.Float32frombits(halfFloatToFloatBits(bigen.Uint16(d.r.readx(2)))))
+	} else if bd == cborBdFloat32 {
+		f = float64(math.Float32frombits(bigen.Uint32(d.r.readx(4))))
+	} else if bd == cborBdFloat64 {
+		f = math.Float64frombits(bigen.Uint64(d.r.readx(8)))
+	} else if bd >= cborBaseUint && bd < cborBaseBytes {
+		f = float64(d.DecodeInt64())
+	} else {
+		d.d.errorf("float only valid from float16/32/64 - invalid descriptor %x/%s", bd, cbordesc(bd))
+		return
+	}
+	d.bdRead = false
+	return
+}
+
+// bool can be decoded from bool only (single byte).
+func (d *cborDecDriver) DecodeBool() (b bool) {
+	if !d.bdRead {
+		d.readNextBd()
+	}
+	if bd := d.bd; bd == cborBdTrue {
+		b = true
+	} else if bd == cborBdFalse {
+	} else {
+		d.d.errorf("not bool - %s %x/%s", msgBadDesc, d.bd, cbordesc(d.bd))
+		return
+	}
+	d.bdRead = false
+	return
+}
+
+func (d *cborDecDriver) ReadMapStart() (length int) {
+	if !d.bdRead {
+		d.readNextBd()
+	}
+	d.bdRead = false
+	if d.bd == cborBdIndefiniteMap {
+		return -1
+	}
+	return d.decLen()
+}
+
+func (d *cborDecDriver) ReadArrayStart() (length int) {
+	if !d.bdRead {
+		d.readNextBd()
+	}
+	d.bdRead = false
+	if d.bd == cborBdIndefiniteArray {
+		return -1
+	}
+	return d.decLen()
+}
+
+func (d *cborDecDriver) decLen() int {
+	return int(d.decUint())
+}
+
+func (d *cborDecDriver) decAppendIndefiniteBytes(bs []byte) []byte {
+	d.bdRead = false
+	for {
+		if d.CheckBreak() {
+			break
+		}
+		if major := d.bd >> 5; major != cborMajorBytes && major != cborMajorText {
+			d.d.errorf("expect bytes/string major type in indefinite string/bytes;"+
+				" got major %v from descriptor %x/%x", major, d.bd, cbordesc(d.bd))
+			return nil
+		}
+		n := d.decLen()
+		oldLen := len(bs)
+		newLen := oldLen + n
+		if newLen > cap(bs) {
+			bs2 := make([]byte, newLen, 2*cap(bs)+n)
+			copy(bs2, bs)
+			bs = bs2
+		} else {
+			bs = bs[:newLen]
+		}
+		d.r.readb(bs[oldLen:newLen])
+		// bs = append(bs, d.r.readn()...)
+		d.bdRead = false
+	}
+	d.bdRead = false
+	return bs
+}
+
+func (d *cborDecDriver) DecodeBytes(bs []byte, zerocopy bool) (bsOut []byte) {
+	if !d.bdRead {
+		d.readNextBd()
+	}
+	if d.bd == cborBdNil || d.bd == cborBdUndefined {
+		d.bdRead = false
+		return nil
+	}
+	if d.bd == cborBdIndefiniteBytes || d.bd == cborBdIndefiniteString {
+		d.bdRead = false
+		if bs == nil {
+			if zerocopy {
+				return d.decAppendIndefiniteBytes(d.d.b[:0])
+			}
+			return d.decAppendIndefiniteBytes(zeroByteSlice)
+		}
+		return d.decAppendIndefiniteBytes(bs[:0])
+	}
+	// check if an "array" of uint8's (see ContainerType for how to infer if an array)
+	if d.bd == cborBdIndefiniteArray || (d.bd >= cborBaseArray && d.bd < cborBaseMap) {
+		bsOut, _ = fastpathTV.DecSliceUint8V(bs, true, d.d)
+		return
+	}
+	clen := d.decLen()
+	d.bdRead = false
+	if zerocopy {
+		if d.br {
+			return d.r.readx(clen)
+		} else if len(bs) == 0 {
+			bs = d.d.b[:]
+		}
+	}
+	return decByteSlice(d.r, clen, d.h.MaxInitLen, bs)
+}
+
+func (d *cborDecDriver) DecodeString() (s string) {
+	return string(d.DecodeBytes(d.d.b[:], true))
+}
+
+func (d *cborDecDriver) DecodeStringAsBytes() (s []byte) {
+	return d.DecodeBytes(d.d.b[:], true)
+}
+
+func (d *cborDecDriver) DecodeTime() (t time.Time) {
+	if !d.bdRead {
+		d.readNextBd()
+	}
+	if d.bd == cborBdNil || d.bd == cborBdUndefined {
+		d.bdRead = false
+		return
+	}
+	xtag := d.decUint()
+	d.bdRead = false
+	return d.decodeTime(xtag)
+}
+
+func (d *cborDecDriver) decodeTime(xtag uint64) (t time.Time) {
+	if !d.bdRead {
+		d.readNextBd()
+	}
+	switch xtag {
+	case 0:
+		var err error
+		if t, err = time.Parse(time.RFC3339, stringView(d.DecodeStringAsBytes())); err != nil {
+			d.d.errorv(err)
+		}
+	case 1:
+		// decode an int64 or a float, and infer time.Time from there.
+		// for floats, round to microseconds, as that is what is guaranteed to fit well.
+		switch {
+		case d.bd == cborBdFloat16, d.bd == cborBdFloat32:
+			f1, f2 := math.Modf(d.DecodeFloat64())
+			t = time.Unix(int64(f1), int64(f2*1e9))
+		case d.bd == cborBdFloat64:
+			f1, f2 := math.Modf(d.DecodeFloat64())
+			t = time.Unix(int64(f1), int64(f2*1e9))
+		case d.bd >= cborBaseUint && d.bd < cborBaseNegInt,
+			d.bd >= cborBaseNegInt && d.bd < cborBaseBytes:
+			t = time.Unix(d.DecodeInt64(), 0)
+		default:
+			d.d.errorf("time.Time can only be decoded from a number (or RFC3339 string)")
+		}
+	default:
+		d.d.errorf("invalid tag for time.Time - expecting 0 or 1, got 0x%x", xtag)
+	}
+	t = t.UTC().Round(time.Microsecond)
+	return
+}
+
+func (d *cborDecDriver) DecodeExt(rv interface{}, xtag uint64, ext Ext) (realxtag uint64) {
+	if !d.bdRead {
+		d.readNextBd()
+	}
+	u := d.decUint()
+	d.bdRead = false
+	realxtag = u
+	if ext == nil {
+		re := rv.(*RawExt)
+		re.Tag = realxtag
+		d.d.decode(&re.Value)
+	} else if xtag != realxtag {
+		d.d.errorf("Wrong extension tag. Got %b. Expecting: %v", realxtag, xtag)
+		return
+	} else {
+		var v interface{}
+		d.d.decode(&v)
+		ext.UpdateExt(rv, v)
+	}
+	d.bdRead = false
+	return
+}
+
+func (d *cborDecDriver) DecodeNaked() {
+	if !d.bdRead {
+		d.readNextBd()
+	}
+
+	n := d.d.n
+	var decodeFurther bool
+
+	switch d.bd {
+	case cborBdNil:
+		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()
+	case cborBdIndefiniteBytes:
+		n.v = valueTypeBytes
+		n.l = d.DecodeBytes(nil, false)
+	case cborBdIndefiniteString:
+		n.v = valueTypeString
+		n.s = d.DecodeString()
+	case cborBdIndefiniteArray:
+		n.v = valueTypeArray
+		decodeFurther = true
+	case cborBdIndefiniteMap:
+		n.v = valueTypeMap
+		decodeFurther = true
+	default:
+		switch {
+		case d.bd >= cborBaseUint && d.bd < cborBaseNegInt:
+			if d.h.SignedInteger {
+				n.v = valueTypeInt
+				n.i = d.DecodeInt64()
+			} else {
+				n.v = valueTypeUint
+				n.u = d.DecodeUint64()
+			}
+		case d.bd >= cborBaseNegInt && d.bd < cborBaseBytes:
+			n.v = valueTypeInt
+			n.i = d.DecodeInt64()
+		case d.bd >= cborBaseBytes && d.bd < cborBaseString:
+			n.v = valueTypeBytes
+			n.l = d.DecodeBytes(nil, false)
+		case d.bd >= cborBaseString && d.bd < cborBaseArray:
+			n.v = valueTypeString
+			n.s = d.DecodeString()
+		case d.bd >= cborBaseArray && d.bd < cborBaseMap:
+			n.v = valueTypeArray
+			decodeFurther = true
+		case d.bd >= cborBaseMap && d.bd < cborBaseTag:
+			n.v = valueTypeMap
+			decodeFurther = true
+		case d.bd >= cborBaseTag && d.bd < cborBaseSimple:
+			n.v = valueTypeExt
+			n.u = d.decUint()
+			n.l = nil
+			if n.u == 0 || n.u == 1 {
+				d.bdRead = false
+				n.v = valueTypeTime
+				n.t = d.decodeTime(n.u)
+			}
+			// d.bdRead = false
+			// d.d.decode(&re.Value) // handled by decode itself.
+			// decodeFurther = true
+		default:
+			d.d.errorf("decodeNaked: Unrecognized d.bd: 0x%x", d.bd)
+			return
+		}
+	}
+
+	if !decodeFurther {
+		d.bdRead = false
+	}
+	return
+}
+
+// -------------------------
+
+// CborHandle is a Handle for the CBOR encoding format,
+// defined at http://tools.ietf.org/html/rfc7049 and documented further at http://cbor.io .
+//
+// CBOR is comprehensively supported, including support for:
+//   - indefinite-length arrays/maps/bytes/strings
+//   - (extension) tags in range 0..0xffff (0 .. 65535)
+//   - half, single and double-precision floats
+//   - all numbers (1, 2, 4 and 8-byte signed and unsigned integers)
+//   - nil, true, false, ...
+//   - arrays and maps, bytes and text strings
+//
+// None of the optional extensions (with tags) defined in the spec are supported out-of-the-box.
+// Users can implement them as needed (using SetExt), including spec-documented ones:
+//   - timestamp, BigNum, BigFloat, Decimals,
+//   - Encoded Text (e.g. URL, regexp, base64, MIME Message), etc.
+type CborHandle struct {
+	binaryEncodingType
+	noElemSeparators
+	BasicHandle
+
+	// IndefiniteLength=true, means that we encode using indefinitelength
+	IndefiniteLength bool
+
+	// TimeRFC3339 says to encode time.Time using RFC3339 format.
+	// If unset, we encode time.Time using seconds past epoch.
+	TimeRFC3339 bool
+
+	// _ [1]uint64 // padding
+}
+
+// Name returns the name of the handle: cbor
+func (h *CborHandle) Name() string { return "cbor" }
+
+// SetInterfaceExt sets an extension
+func (h *CborHandle) SetInterfaceExt(rt reflect.Type, tag uint64, ext InterfaceExt) (err error) {
+	return h.SetExt(rt, tag, &extWrapper{bytesExtFailer{}, ext})
+}
+
+func (h *CborHandle) newEncDriver(e *Encoder) encDriver {
+	return &cborEncDriver{e: e, w: e.w, h: h}
+}
+
+func (h *CborHandle) newDecDriver(d *Decoder) decDriver {
+	return &cborDecDriver{d: d, h: h, r: d.r, br: d.bytes}
+}
+
+func (e *cborEncDriver) reset() {
+	e.w = e.e.w
+}
+
+func (d *cborDecDriver) reset() {
+	d.r, d.br = d.d.r, d.d.bytes
+	d.bd, d.bdRead = 0, false
+}
+
+var _ decDriver = (*cborDecDriver)(nil)
+var _ encDriver = (*cborEncDriver)(nil)