| // 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 |
| _ [2]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 |
| } |
| xbs = d.r.readx(l) |
| 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()) |
| n.l = d.r.readx(l) |
| 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) |
