--- /dev/null
+// 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 (
+ _ uint8 = iota
+ simpleVdNil = 1
+ simpleVdFalse = 2
+ simpleVdTrue = 3
+ simpleVdFloat32 = 4
+ simpleVdFloat64 = 5
+
+ // each lasts for 4 (ie n, n+1, n+2, n+3)
+ simpleVdPosInt = 8
+ simpleVdNegInt = 12
+
+ simpleVdTime = 24
+
+ // containers: each lasts for 4 (ie n, n+1, n+2, ... n+7)
+ simpleVdString = 216
+ simpleVdByteArray = 224
+ simpleVdArray = 232
+ simpleVdMap = 240
+ simpleVdExt = 248
+)
+
+type simpleEncDriver struct {
+ noBuiltInTypes
+ // encNoSeparator
+ e *Encoder
+ h *SimpleHandle
+ w encWriter
+ b [8]byte
+ // c containerState
+ encDriverTrackContainerWriter
+ // encDriverNoopContainerWriter
+ _ [3]uint64 // padding
+}
+
+func (e *simpleEncDriver) EncodeNil() {
+ e.w.writen1(simpleVdNil)
+}
+
+func (e *simpleEncDriver) EncodeBool(b bool) {
+ if e.h.EncZeroValuesAsNil && e.c != containerMapKey && !b {
+ e.EncodeNil()
+ return
+ }
+ if b {
+ e.w.writen1(simpleVdTrue)
+ } else {
+ e.w.writen1(simpleVdFalse)
+ }
+}
+
+func (e *simpleEncDriver) EncodeFloat32(f float32) {
+ if e.h.EncZeroValuesAsNil && e.c != containerMapKey && f == 0.0 {
+ e.EncodeNil()
+ return
+ }
+ e.w.writen1(simpleVdFloat32)
+ bigenHelper{e.b[:4], e.w}.writeUint32(math.Float32bits(f))
+}
+
+func (e *simpleEncDriver) EncodeFloat64(f float64) {
+ if e.h.EncZeroValuesAsNil && e.c != containerMapKey && f == 0.0 {
+ e.EncodeNil()
+ return
+ }
+ e.w.writen1(simpleVdFloat64)
+ bigenHelper{e.b[:8], e.w}.writeUint64(math.Float64bits(f))
+}
+
+func (e *simpleEncDriver) EncodeInt(v int64) {
+ if v < 0 {
+ e.encUint(uint64(-v), simpleVdNegInt)
+ } else {
+ e.encUint(uint64(v), simpleVdPosInt)
+ }
+}
+
+func (e *simpleEncDriver) EncodeUint(v uint64) {
+ e.encUint(v, simpleVdPosInt)
+}
+
+func (e *simpleEncDriver) encUint(v uint64, bd uint8) {
+ if e.h.EncZeroValuesAsNil && e.c != containerMapKey && v == 0 {
+ e.EncodeNil()
+ return
+ }
+ if v <= math.MaxUint8 {
+ e.w.writen2(bd, uint8(v))
+ } else if v <= math.MaxUint16 {
+ e.w.writen1(bd + 1)
+ bigenHelper{e.b[:2], e.w}.writeUint16(uint16(v))
+ } else if v <= math.MaxUint32 {
+ e.w.writen1(bd + 2)
+ bigenHelper{e.b[:4], e.w}.writeUint32(uint32(v))
+ } else { // if v <= math.MaxUint64 {
+ e.w.writen1(bd + 3)
+ bigenHelper{e.b[:8], e.w}.writeUint64(v)
+ }
+}
+
+func (e *simpleEncDriver) encLen(bd byte, length int) {
+ if length == 0 {
+ e.w.writen1(bd)
+ } else if length <= math.MaxUint8 {
+ e.w.writen1(bd + 1)
+ e.w.writen1(uint8(length))
+ } else if length <= math.MaxUint16 {
+ e.w.writen1(bd + 2)
+ bigenHelper{e.b[:2], e.w}.writeUint16(uint16(length))
+ } else if int64(length) <= math.MaxUint32 {
+ e.w.writen1(bd + 3)
+ bigenHelper{e.b[:4], e.w}.writeUint32(uint32(length))
+ } else {
+ e.w.writen1(bd + 4)
+ bigenHelper{e.b[:8], e.w}.writeUint64(uint64(length))
+ }
+}
+
+func (e *simpleEncDriver) EncodeExt(rv interface{}, xtag uint64, ext Ext, _ *Encoder) {
+ bs := ext.WriteExt(rv)
+ if bs == nil {
+ e.EncodeNil()
+ return
+ }
+ e.encodeExtPreamble(uint8(xtag), len(bs))
+ e.w.writeb(bs)
+}
+
+func (e *simpleEncDriver) EncodeRawExt(re *RawExt, _ *Encoder) {
+ e.encodeExtPreamble(uint8(re.Tag), len(re.Data))
+ e.w.writeb(re.Data)
+}
+
+func (e *simpleEncDriver) encodeExtPreamble(xtag byte, length int) {
+ e.encLen(simpleVdExt, length)
+ e.w.writen1(xtag)
+}
+
+func (e *simpleEncDriver) WriteArrayStart(length int) {
+ e.c = containerArrayStart
+ e.encLen(simpleVdArray, length)
+}
+
+func (e *simpleEncDriver) WriteMapStart(length int) {
+ e.c = containerMapStart
+ e.encLen(simpleVdMap, length)
+}
+
+func (e *simpleEncDriver) EncodeString(c charEncoding, v string) {
+ if false && e.h.EncZeroValuesAsNil && e.c != containerMapKey && v == "" {
+ e.EncodeNil()
+ return
+ }
+ e.encLen(simpleVdString, len(v))
+ e.w.writestr(v)
+}
+
+// func (e *simpleEncDriver) EncodeSymbol(v string) {
+// e.EncodeString(cUTF8, v)
+// }
+
+func (e *simpleEncDriver) EncodeStringBytes(c charEncoding, v []byte) {
+ // if e.h.EncZeroValuesAsNil && e.c != containerMapKey && v == nil {
+ if v == nil {
+ e.EncodeNil()
+ return
+ }
+ e.encLen(simpleVdByteArray, len(v))
+ e.w.writeb(v)
+}
+
+func (e *simpleEncDriver) EncodeTime(t time.Time) {
+ // if e.h.EncZeroValuesAsNil && e.c != containerMapKey && t.IsZero() {
+ if t.IsZero() {
+ e.EncodeNil()
+ return
+ }
+ v, err := t.MarshalBinary()
+ if err != nil {
+ e.e.errorv(err)
+ return
+ }
+ // time.Time marshalbinary takes about 14 bytes.
+ e.w.writen2(simpleVdTime, uint8(len(v)))
+ e.w.writeb(v)
+}
+
+//------------------------------------
+
+type simpleDecDriver struct {
+ d *Decoder
+ h *SimpleHandle
+ r decReader
+ bdRead bool
+ bd byte
+ br bool // a bytes reader?
+ c containerState
+ // b [scratchByteArrayLen]byte
+ noBuiltInTypes
+ // noStreamingCodec
+ decDriverNoopContainerReader
+ // _ [3]uint64 // padding
+}
+
+func (d *simpleDecDriver) readNextBd() {
+ d.bd = d.r.readn1()
+ d.bdRead = true
+}
+
+func (d *simpleDecDriver) uncacheRead() {
+ if d.bdRead {
+ d.r.unreadn1()
+ d.bdRead = false
+ }
+}
+
+func (d *simpleDecDriver) ContainerType() (vt valueType) {
+ if !d.bdRead {
+ d.readNextBd()
+ }
+ switch d.bd {
+ case simpleVdNil:
+ return valueTypeNil
+ case simpleVdByteArray, simpleVdByteArray + 1,
+ simpleVdByteArray + 2, simpleVdByteArray + 3, simpleVdByteArray + 4:
+ return valueTypeBytes
+ case simpleVdString, simpleVdString + 1,
+ simpleVdString + 2, simpleVdString + 3, simpleVdString + 4:
+ return valueTypeString
+ case simpleVdArray, simpleVdArray + 1,
+ simpleVdArray + 2, simpleVdArray + 3, simpleVdArray + 4:
+ return valueTypeArray
+ case simpleVdMap, simpleVdMap + 1,
+ simpleVdMap + 2, simpleVdMap + 3, simpleVdMap + 4:
+ return valueTypeMap
+ // case simpleVdTime:
+ // return valueTypeTime
+ }
+ // else {
+ // d.d.errorf("isContainerType: unsupported parameter: %v", vt)
+ // }
+ return valueTypeUnset
+}
+
+func (d *simpleDecDriver) TryDecodeAsNil() bool {
+ if !d.bdRead {
+ d.readNextBd()
+ }
+ if d.bd == simpleVdNil {
+ d.bdRead = false
+ return true
+ }
+ return false
+}
+
+func (d *simpleDecDriver) decCheckInteger() (ui uint64, neg bool) {
+ if !d.bdRead {
+ d.readNextBd()
+ }
+ switch d.bd {
+ case simpleVdPosInt:
+ ui = uint64(d.r.readn1())
+ case simpleVdPosInt + 1:
+ ui = uint64(bigen.Uint16(d.r.readx(2)))
+ case simpleVdPosInt + 2:
+ ui = uint64(bigen.Uint32(d.r.readx(4)))
+ case simpleVdPosInt + 3:
+ ui = uint64(bigen.Uint64(d.r.readx(8)))
+ case simpleVdNegInt:
+ ui = uint64(d.r.readn1())
+ neg = true
+ case simpleVdNegInt + 1:
+ ui = uint64(bigen.Uint16(d.r.readx(2)))
+ neg = true
+ case simpleVdNegInt + 2:
+ ui = uint64(bigen.Uint32(d.r.readx(4)))
+ neg = true
+ case simpleVdNegInt + 3:
+ ui = uint64(bigen.Uint64(d.r.readx(8)))
+ neg = true
+ default:
+ d.d.errorf("integer only valid from pos/neg integer1..8. Invalid descriptor: %v", d.bd)
+ return
+ }
+ // don't do this check, because callers may only want the unsigned value.
+ // if ui > math.MaxInt64 {
+ // d.d.errorf("decIntAny: Integer out of range for signed int64: %v", ui)
+ // return
+ // }
+ return
+}
+
+func (d *simpleDecDriver) DecodeInt64() (i int64) {
+ ui, neg := d.decCheckInteger()
+ i = chkOvf.SignedIntV(ui)
+ if neg {
+ i = -i
+ }
+ d.bdRead = false
+ return
+}
+
+func (d *simpleDecDriver) DecodeUint64() (ui uint64) {
+ ui, neg := d.decCheckInteger()
+ if neg {
+ d.d.errorf("assigning negative signed value to unsigned type")
+ return
+ }
+ d.bdRead = false
+ return
+}
+
+func (d *simpleDecDriver) DecodeFloat64() (f float64) {
+ if !d.bdRead {
+ d.readNextBd()
+ }
+ if d.bd == simpleVdFloat32 {
+ f = float64(math.Float32frombits(bigen.Uint32(d.r.readx(4))))
+ } else if d.bd == simpleVdFloat64 {
+ f = math.Float64frombits(bigen.Uint64(d.r.readx(8)))
+ } else {
+ if d.bd >= simpleVdPosInt && d.bd <= simpleVdNegInt+3 {
+ f = float64(d.DecodeInt64())
+ } else {
+ d.d.errorf("float only valid from float32/64: Invalid descriptor: %v", d.bd)
+ return
+ }
+ }
+ d.bdRead = false
+ return
+}
+
+// bool can be decoded from bool only (single byte).
+func (d *simpleDecDriver) DecodeBool() (b bool) {
+ if !d.bdRead {
+ d.readNextBd()
+ }
+ if d.bd == simpleVdTrue {
+ b = true
+ } else if d.bd == simpleVdFalse {
+ } else {
+ d.d.errorf("cannot decode bool - %s: %x", msgBadDesc, d.bd)
+ return
+ }
+ d.bdRead = false
+ return
+}
+
+func (d *simpleDecDriver) ReadMapStart() (length int) {
+ if !d.bdRead {
+ d.readNextBd()
+ }
+ d.bdRead = false
+ d.c = containerMapStart
+ return d.decLen()
+}
+
+func (d *simpleDecDriver) ReadArrayStart() (length int) {
+ if !d.bdRead {
+ d.readNextBd()
+ }
+ d.bdRead = false
+ d.c = containerArrayStart
+ return d.decLen()
+}
+
+func (d *simpleDecDriver) ReadArrayElem() {
+ d.c = containerArrayElem
+}
+
+func (d *simpleDecDriver) ReadArrayEnd() {
+ d.c = containerArrayEnd
+}
+
+func (d *simpleDecDriver) ReadMapElemKey() {
+ d.c = containerMapKey
+}
+
+func (d *simpleDecDriver) ReadMapElemValue() {
+ d.c = containerMapValue
+}
+
+func (d *simpleDecDriver) ReadMapEnd() {
+ d.c = containerMapEnd
+}
+
+func (d *simpleDecDriver) decLen() int {
+ switch d.bd % 8 {
+ case 0:
+ return 0
+ case 1:
+ return int(d.r.readn1())
+ case 2:
+ return int(bigen.Uint16(d.r.readx(2)))
+ case 3:
+ ui := uint64(bigen.Uint32(d.r.readx(4)))
+ if chkOvf.Uint(ui, intBitsize) {
+ d.d.errorf("overflow integer: %v", ui)
+ return 0
+ }
+ return int(ui)
+ case 4:
+ ui := bigen.Uint64(d.r.readx(8))
+ if chkOvf.Uint(ui, intBitsize) {
+ d.d.errorf("overflow integer: %v", ui)
+ return 0
+ }
+ return int(ui)
+ }
+ d.d.errorf("cannot read length: bd%%8 must be in range 0..4. Got: %d", d.bd%8)
+ return -1
+}
+
+func (d *simpleDecDriver) DecodeString() (s string) {
+ return string(d.DecodeBytes(d.d.b[:], true))
+}
+
+func (d *simpleDecDriver) DecodeStringAsBytes() (s []byte) {
+ return d.DecodeBytes(d.d.b[:], true)
+}
+
+func (d *simpleDecDriver) DecodeBytes(bs []byte, zerocopy bool) (bsOut []byte) {
+ if !d.bdRead {
+ d.readNextBd()
+ }
+ if d.bd == simpleVdNil {
+ d.bdRead = false
+ return
+ }
+ // check if an "array" of uint8's (see ContainerType for how to infer if an array)
+ if d.bd >= simpleVdArray && d.bd <= simpleVdMap+4 {
+ if len(bs) == 0 && zerocopy {
+ bs = d.d.b[:]
+ }
+ 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.d.h.MaxInitLen, bs)
+}
+
+func (d *simpleDecDriver) DecodeTime() (t time.Time) {
+ if !d.bdRead {
+ d.readNextBd()
+ }
+ if d.bd == simpleVdNil {
+ d.bdRead = false
+ return
+ }
+ if d.bd != simpleVdTime {
+ d.d.errorf("invalid descriptor for time.Time - expect 0x%x, received 0x%x", simpleVdTime, d.bd)
+ return
+ }
+ d.bdRead = false
+ clen := int(d.r.readn1())
+ b := d.r.readx(clen)
+ if err := (&t).UnmarshalBinary(b); err != nil {
+ d.d.errorv(err)
+ }
+ return
+}
+
+func (d *simpleDecDriver) DecodeExt(rv interface{}, xtag uint64, ext Ext) (realxtag uint64) {
+ if xtag > 0xff {
+ d.d.errorf("ext: tag must be <= 0xff; got: %v", xtag)
+ return
+ }
+ realxtag1, xbs := d.decodeExtV(ext != nil, uint8(xtag))
+ realxtag = uint64(realxtag1)
+ if ext == nil {
+ re := rv.(*RawExt)
+ re.Tag = realxtag
+ re.Data = detachZeroCopyBytes(d.br, re.Data, xbs)
+ } else {
+ ext.ReadExt(rv, xbs)
+ }
+ return
+}
+
+func (d *simpleDecDriver) decodeExtV(verifyTag bool, tag byte) (xtag byte, xbs []byte) {
+ if !d.bdRead {
+ d.readNextBd()
+ }
+ switch d.bd {
+ case simpleVdExt, simpleVdExt + 1, simpleVdExt + 2, simpleVdExt + 3, simpleVdExt + 4:
+ l := d.decLen()
+ xtag = d.r.readn1()
+ if verifyTag && xtag != tag {
+ d.d.errorf("wrong extension tag. Got %b. Expecting: %v", xtag, tag)
+ return
+ }
+ if d.br {
+ xbs = d.r.readx(l)
+ } else {
+ xbs = decByteSlice(d.r, l, d.d.h.MaxInitLen, d.d.b[:])
+ }
+ case simpleVdByteArray, simpleVdByteArray + 1,
+ simpleVdByteArray + 2, simpleVdByteArray + 3, simpleVdByteArray + 4:
+ xbs = d.DecodeBytes(nil, true)
+ default:
+ d.d.errorf("ext - %s - expecting extensions/bytearray, got: 0x%x", msgBadDesc, d.bd)
+ return
+ }
+ d.bdRead = false
+ return
+}
+
+func (d *simpleDecDriver) DecodeNaked() {
+ if !d.bdRead {
+ d.readNextBd()
+ }
+
+ n := d.d.n
+ var decodeFurther bool
+
+ switch d.bd {
+ case simpleVdNil:
+ n.v = valueTypeNil
+ case simpleVdFalse:
+ n.v = valueTypeBool
+ n.b = false
+ case simpleVdTrue:
+ n.v = valueTypeBool
+ n.b = true
+ case simpleVdPosInt, simpleVdPosInt + 1, simpleVdPosInt + 2, simpleVdPosInt + 3:
+ if d.h.SignedInteger {
+ n.v = valueTypeInt
+ n.i = d.DecodeInt64()
+ } else {
+ n.v = valueTypeUint
+ n.u = d.DecodeUint64()
+ }
+ case simpleVdNegInt, simpleVdNegInt + 1, simpleVdNegInt + 2, simpleVdNegInt + 3:
+ n.v = valueTypeInt
+ n.i = d.DecodeInt64()
+ case simpleVdFloat32:
+ n.v = valueTypeFloat
+ n.f = d.DecodeFloat64()
+ case simpleVdFloat64:
+ n.v = valueTypeFloat
+ n.f = d.DecodeFloat64()
+ case simpleVdTime:
+ n.v = valueTypeTime
+ n.t = d.DecodeTime()
+ case simpleVdString, simpleVdString + 1,
+ simpleVdString + 2, simpleVdString + 3, simpleVdString + 4:
+ n.v = valueTypeString
+ n.s = d.DecodeString()
+ case simpleVdByteArray, simpleVdByteArray + 1,
+ simpleVdByteArray + 2, simpleVdByteArray + 3, simpleVdByteArray + 4:
+ n.v = valueTypeBytes
+ n.l = d.DecodeBytes(nil, false)
+ case simpleVdExt, simpleVdExt + 1, simpleVdExt + 2, simpleVdExt + 3, simpleVdExt + 4:
+ n.v = valueTypeExt
+ l := d.decLen()
+ n.u = uint64(d.r.readn1())
+ if d.br {
+ n.l = d.r.readx(l)
+ } else {
+ n.l = decByteSlice(d.r, l, d.d.h.MaxInitLen, d.d.b[:])
+ }
+ case simpleVdArray, simpleVdArray + 1, simpleVdArray + 2,
+ simpleVdArray + 3, simpleVdArray + 4:
+ n.v = valueTypeArray
+ decodeFurther = true
+ case simpleVdMap, simpleVdMap + 1, simpleVdMap + 2, simpleVdMap + 3, simpleVdMap + 4:
+ n.v = valueTypeMap
+ decodeFurther = true
+ default:
+ d.d.errorf("cannot infer value - %s 0x%x", msgBadDesc, d.bd)
+ }
+
+ if !decodeFurther {
+ d.bdRead = false
+ }
+ return
+}
+
+//------------------------------------
+
+// SimpleHandle is a Handle for a very simple encoding format.
+//
+// simple is a simplistic codec similar to binc, but not as compact.
+// - Encoding of a value is always preceded by the descriptor byte (bd)
+// - True, false, nil are encoded fully in 1 byte (the descriptor)
+// - Integers (intXXX, uintXXX) are encoded in 1, 2, 4 or 8 bytes (plus a descriptor byte).
+// There are positive (uintXXX and intXXX >= 0) and negative (intXXX < 0) integers.
+// - Floats are encoded in 4 or 8 bytes (plus a descriptor byte)
+// - Length of containers (strings, bytes, array, map, extensions)
+// are encoded in 0, 1, 2, 4 or 8 bytes.
+// Zero-length containers have no length encoded.
+// For others, the number of bytes is given by pow(2, bd%3)
+// - maps are encoded as [bd] [length] [[key][value]]...
+// - arrays are encoded as [bd] [length] [value]...
+// - extensions are encoded as [bd] [length] [tag] [byte]...
+// - strings/bytearrays are encoded as [bd] [length] [byte]...
+// - time.Time are encoded as [bd] [length] [byte]...
+//
+// The full spec will be published soon.
+type SimpleHandle struct {
+ BasicHandle
+ binaryEncodingType
+ noElemSeparators
+ // EncZeroValuesAsNil says to encode zero values for numbers, bool, string, etc as nil
+ EncZeroValuesAsNil bool
+
+ // _ [1]uint64 // padding
+}
+
+// Name returns the name of the handle: simple
+func (h *SimpleHandle) Name() string { return "simple" }
+
+// SetBytesExt sets an extension
+func (h *SimpleHandle) SetBytesExt(rt reflect.Type, tag uint64, ext BytesExt) (err error) {
+ return h.SetExt(rt, tag, &extWrapper{ext, interfaceExtFailer{}})
+}
+
+func (h *SimpleHandle) hasElemSeparators() bool { return true } // as it implements Write(Map|Array)XXX
+
+func (h *SimpleHandle) newEncDriver(e *Encoder) encDriver {
+ return &simpleEncDriver{e: e, w: e.w, h: h}
+}
+
+func (h *SimpleHandle) newDecDriver(d *Decoder) decDriver {
+ return &simpleDecDriver{d: d, h: h, r: d.r, br: d.bytes}
+}
+
+func (e *simpleEncDriver) reset() {
+ e.c = 0
+ e.w = e.e.w
+}
+
+func (d *simpleDecDriver) reset() {
+ d.c = 0
+ d.r, d.br = d.d.r, d.d.bytes
+ d.bd, d.bdRead = 0, false
+}
+
+var _ decDriver = (*simpleDecDriver)(nil)
+var _ encDriver = (*simpleEncDriver)(nil)
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