1 // Copyright (c) 2012-2018 Ugorji Nwoke. All rights reserved.
2 // Use of this source code is governed by a MIT license found in the LICENSE file.
20 // each lasts for 4 (ie n, n+1, n+2, n+3)
26 // containers: each lasts for 4 (ie n, n+1, n+2, ... n+7)
28 simpleVdByteArray = 224
34 type simpleEncDriver struct {
42 encDriverTrackContainerWriter
43 // encDriverNoopContainerWriter
44 _ [3]uint64 // padding
47 func (e *simpleEncDriver) EncodeNil() {
48 e.w.writen1(simpleVdNil)
51 func (e *simpleEncDriver) EncodeBool(b bool) {
52 if e.h.EncZeroValuesAsNil && e.c != containerMapKey && !b {
57 e.w.writen1(simpleVdTrue)
59 e.w.writen1(simpleVdFalse)
63 func (e *simpleEncDriver) EncodeFloat32(f float32) {
64 if e.h.EncZeroValuesAsNil && e.c != containerMapKey && f == 0.0 {
68 e.w.writen1(simpleVdFloat32)
69 bigenHelper{e.b[:4], e.w}.writeUint32(math.Float32bits(f))
72 func (e *simpleEncDriver) EncodeFloat64(f float64) {
73 if e.h.EncZeroValuesAsNil && e.c != containerMapKey && f == 0.0 {
77 e.w.writen1(simpleVdFloat64)
78 bigenHelper{e.b[:8], e.w}.writeUint64(math.Float64bits(f))
81 func (e *simpleEncDriver) EncodeInt(v int64) {
83 e.encUint(uint64(-v), simpleVdNegInt)
85 e.encUint(uint64(v), simpleVdPosInt)
89 func (e *simpleEncDriver) EncodeUint(v uint64) {
90 e.encUint(v, simpleVdPosInt)
93 func (e *simpleEncDriver) encUint(v uint64, bd uint8) {
94 if e.h.EncZeroValuesAsNil && e.c != containerMapKey && v == 0 {
98 if v <= math.MaxUint8 {
99 e.w.writen2(bd, uint8(v))
100 } else if v <= math.MaxUint16 {
102 bigenHelper{e.b[:2], e.w}.writeUint16(uint16(v))
103 } else if v <= math.MaxUint32 {
105 bigenHelper{e.b[:4], e.w}.writeUint32(uint32(v))
106 } else { // if v <= math.MaxUint64 {
108 bigenHelper{e.b[:8], e.w}.writeUint64(v)
112 func (e *simpleEncDriver) encLen(bd byte, length int) {
115 } else if length <= math.MaxUint8 {
117 e.w.writen1(uint8(length))
118 } else if length <= math.MaxUint16 {
120 bigenHelper{e.b[:2], e.w}.writeUint16(uint16(length))
121 } else if int64(length) <= math.MaxUint32 {
123 bigenHelper{e.b[:4], e.w}.writeUint32(uint32(length))
126 bigenHelper{e.b[:8], e.w}.writeUint64(uint64(length))
130 func (e *simpleEncDriver) EncodeExt(rv interface{}, xtag uint64, ext Ext, _ *Encoder) {
131 bs := ext.WriteExt(rv)
136 e.encodeExtPreamble(uint8(xtag), len(bs))
140 func (e *simpleEncDriver) EncodeRawExt(re *RawExt, _ *Encoder) {
141 e.encodeExtPreamble(uint8(re.Tag), len(re.Data))
145 func (e *simpleEncDriver) encodeExtPreamble(xtag byte, length int) {
146 e.encLen(simpleVdExt, length)
150 func (e *simpleEncDriver) WriteArrayStart(length int) {
151 e.c = containerArrayStart
152 e.encLen(simpleVdArray, length)
155 func (e *simpleEncDriver) WriteMapStart(length int) {
156 e.c = containerMapStart
157 e.encLen(simpleVdMap, length)
160 func (e *simpleEncDriver) EncodeString(c charEncoding, v string) {
161 if false && e.h.EncZeroValuesAsNil && e.c != containerMapKey && v == "" {
165 e.encLen(simpleVdString, len(v))
169 // func (e *simpleEncDriver) EncodeSymbol(v string) {
170 // e.EncodeString(cUTF8, v)
173 func (e *simpleEncDriver) EncodeStringBytes(c charEncoding, v []byte) {
174 // if e.h.EncZeroValuesAsNil && e.c != containerMapKey && v == nil {
179 e.encLen(simpleVdByteArray, len(v))
183 func (e *simpleEncDriver) EncodeTime(t time.Time) {
184 // if e.h.EncZeroValuesAsNil && e.c != containerMapKey && t.IsZero() {
189 v, err := t.MarshalBinary()
194 // time.Time marshalbinary takes about 14 bytes.
195 e.w.writen2(simpleVdTime, uint8(len(v)))
199 //------------------------------------
201 type simpleDecDriver struct {
207 br bool // a bytes reader?
209 // b [scratchByteArrayLen]byte
212 decDriverNoopContainerReader
213 // _ [3]uint64 // padding
216 func (d *simpleDecDriver) readNextBd() {
221 func (d *simpleDecDriver) uncacheRead() {
228 func (d *simpleDecDriver) ContainerType() (vt valueType) {
235 case simpleVdByteArray, simpleVdByteArray + 1,
236 simpleVdByteArray + 2, simpleVdByteArray + 3, simpleVdByteArray + 4:
237 return valueTypeBytes
238 case simpleVdString, simpleVdString + 1,
239 simpleVdString + 2, simpleVdString + 3, simpleVdString + 4:
240 return valueTypeString
241 case simpleVdArray, simpleVdArray + 1,
242 simpleVdArray + 2, simpleVdArray + 3, simpleVdArray + 4:
243 return valueTypeArray
244 case simpleVdMap, simpleVdMap + 1,
245 simpleVdMap + 2, simpleVdMap + 3, simpleVdMap + 4:
247 // case simpleVdTime:
248 // return valueTypeTime
251 // d.d.errorf("isContainerType: unsupported parameter: %v", vt)
253 return valueTypeUnset
256 func (d *simpleDecDriver) TryDecodeAsNil() bool {
260 if d.bd == simpleVdNil {
267 func (d *simpleDecDriver) decCheckInteger() (ui uint64, neg bool) {
273 ui = uint64(d.r.readn1())
274 case simpleVdPosInt + 1:
275 ui = uint64(bigen.Uint16(d.r.readx(2)))
276 case simpleVdPosInt + 2:
277 ui = uint64(bigen.Uint32(d.r.readx(4)))
278 case simpleVdPosInt + 3:
279 ui = uint64(bigen.Uint64(d.r.readx(8)))
281 ui = uint64(d.r.readn1())
283 case simpleVdNegInt + 1:
284 ui = uint64(bigen.Uint16(d.r.readx(2)))
286 case simpleVdNegInt + 2:
287 ui = uint64(bigen.Uint32(d.r.readx(4)))
289 case simpleVdNegInt + 3:
290 ui = uint64(bigen.Uint64(d.r.readx(8)))
293 d.d.errorf("integer only valid from pos/neg integer1..8. Invalid descriptor: %v", d.bd)
296 // don't do this check, because callers may only want the unsigned value.
297 // if ui > math.MaxInt64 {
298 // d.d.errorf("decIntAny: Integer out of range for signed int64: %v", ui)
304 func (d *simpleDecDriver) DecodeInt64() (i int64) {
305 ui, neg := d.decCheckInteger()
306 i = chkOvf.SignedIntV(ui)
314 func (d *simpleDecDriver) DecodeUint64() (ui uint64) {
315 ui, neg := d.decCheckInteger()
317 d.d.errorf("assigning negative signed value to unsigned type")
324 func (d *simpleDecDriver) DecodeFloat64() (f float64) {
328 if d.bd == simpleVdFloat32 {
329 f = float64(math.Float32frombits(bigen.Uint32(d.r.readx(4))))
330 } else if d.bd == simpleVdFloat64 {
331 f = math.Float64frombits(bigen.Uint64(d.r.readx(8)))
333 if d.bd >= simpleVdPosInt && d.bd <= simpleVdNegInt+3 {
334 f = float64(d.DecodeInt64())
336 d.d.errorf("float only valid from float32/64: Invalid descriptor: %v", d.bd)
344 // bool can be decoded from bool only (single byte).
345 func (d *simpleDecDriver) DecodeBool() (b bool) {
349 if d.bd == simpleVdTrue {
351 } else if d.bd == simpleVdFalse {
353 d.d.errorf("cannot decode bool - %s: %x", msgBadDesc, d.bd)
360 func (d *simpleDecDriver) ReadMapStart() (length int) {
365 d.c = containerMapStart
369 func (d *simpleDecDriver) ReadArrayStart() (length int) {
374 d.c = containerArrayStart
378 func (d *simpleDecDriver) ReadArrayElem() {
379 d.c = containerArrayElem
382 func (d *simpleDecDriver) ReadArrayEnd() {
383 d.c = containerArrayEnd
386 func (d *simpleDecDriver) ReadMapElemKey() {
387 d.c = containerMapKey
390 func (d *simpleDecDriver) ReadMapElemValue() {
391 d.c = containerMapValue
394 func (d *simpleDecDriver) ReadMapEnd() {
395 d.c = containerMapEnd
398 func (d *simpleDecDriver) decLen() int {
403 return int(d.r.readn1())
405 return int(bigen.Uint16(d.r.readx(2)))
407 ui := uint64(bigen.Uint32(d.r.readx(4)))
408 if chkOvf.Uint(ui, intBitsize) {
409 d.d.errorf("overflow integer: %v", ui)
414 ui := bigen.Uint64(d.r.readx(8))
415 if chkOvf.Uint(ui, intBitsize) {
416 d.d.errorf("overflow integer: %v", ui)
421 d.d.errorf("cannot read length: bd%%8 must be in range 0..4. Got: %d", d.bd%8)
425 func (d *simpleDecDriver) DecodeString() (s string) {
426 return string(d.DecodeBytes(d.d.b[:], true))
429 func (d *simpleDecDriver) DecodeStringAsBytes() (s []byte) {
430 return d.DecodeBytes(d.d.b[:], true)
433 func (d *simpleDecDriver) DecodeBytes(bs []byte, zerocopy bool) (bsOut []byte) {
437 if d.bd == simpleVdNil {
441 // check if an "array" of uint8's (see ContainerType for how to infer if an array)
442 if d.bd >= simpleVdArray && d.bd <= simpleVdMap+4 {
443 if len(bs) == 0 && zerocopy {
446 bsOut, _ = fastpathTV.DecSliceUint8V(bs, true, d.d)
454 return d.r.readx(clen)
455 } else if len(bs) == 0 {
459 return decByteSlice(d.r, clen, d.d.h.MaxInitLen, bs)
462 func (d *simpleDecDriver) DecodeTime() (t time.Time) {
466 if d.bd == simpleVdNil {
470 if d.bd != simpleVdTime {
471 d.d.errorf("invalid descriptor for time.Time - expect 0x%x, received 0x%x", simpleVdTime, d.bd)
475 clen := int(d.r.readn1())
477 if err := (&t).UnmarshalBinary(b); err != nil {
483 func (d *simpleDecDriver) DecodeExt(rv interface{}, xtag uint64, ext Ext) (realxtag uint64) {
485 d.d.errorf("ext: tag must be <= 0xff; got: %v", xtag)
488 realxtag1, xbs := d.decodeExtV(ext != nil, uint8(xtag))
489 realxtag = uint64(realxtag1)
493 re.Data = detachZeroCopyBytes(d.br, re.Data, xbs)
500 func (d *simpleDecDriver) decodeExtV(verifyTag bool, tag byte) (xtag byte, xbs []byte) {
505 case simpleVdExt, simpleVdExt + 1, simpleVdExt + 2, simpleVdExt + 3, simpleVdExt + 4:
508 if verifyTag && xtag != tag {
509 d.d.errorf("wrong extension tag. Got %b. Expecting: %v", xtag, tag)
515 xbs = decByteSlice(d.r, l, d.d.h.MaxInitLen, d.d.b[:])
517 case simpleVdByteArray, simpleVdByteArray + 1,
518 simpleVdByteArray + 2, simpleVdByteArray + 3, simpleVdByteArray + 4:
519 xbs = d.DecodeBytes(nil, true)
521 d.d.errorf("ext - %s - expecting extensions/bytearray, got: 0x%x", msgBadDesc, d.bd)
528 func (d *simpleDecDriver) DecodeNaked() {
534 var decodeFurther bool
545 case simpleVdPosInt, simpleVdPosInt + 1, simpleVdPosInt + 2, simpleVdPosInt + 3:
546 if d.h.SignedInteger {
548 n.i = d.DecodeInt64()
551 n.u = d.DecodeUint64()
553 case simpleVdNegInt, simpleVdNegInt + 1, simpleVdNegInt + 2, simpleVdNegInt + 3:
555 n.i = d.DecodeInt64()
556 case simpleVdFloat32:
558 n.f = d.DecodeFloat64()
559 case simpleVdFloat64:
561 n.f = d.DecodeFloat64()
565 case simpleVdString, simpleVdString + 1,
566 simpleVdString + 2, simpleVdString + 3, simpleVdString + 4:
567 n.v = valueTypeString
568 n.s = d.DecodeString()
569 case simpleVdByteArray, simpleVdByteArray + 1,
570 simpleVdByteArray + 2, simpleVdByteArray + 3, simpleVdByteArray + 4:
572 n.l = d.DecodeBytes(nil, false)
573 case simpleVdExt, simpleVdExt + 1, simpleVdExt + 2, simpleVdExt + 3, simpleVdExt + 4:
576 n.u = uint64(d.r.readn1())
580 n.l = decByteSlice(d.r, l, d.d.h.MaxInitLen, d.d.b[:])
582 case simpleVdArray, simpleVdArray + 1, simpleVdArray + 2,
583 simpleVdArray + 3, simpleVdArray + 4:
586 case simpleVdMap, simpleVdMap + 1, simpleVdMap + 2, simpleVdMap + 3, simpleVdMap + 4:
590 d.d.errorf("cannot infer value - %s 0x%x", msgBadDesc, d.bd)
599 //------------------------------------
601 // SimpleHandle is a Handle for a very simple encoding format.
603 // simple is a simplistic codec similar to binc, but not as compact.
604 // - Encoding of a value is always preceded by the descriptor byte (bd)
605 // - True, false, nil are encoded fully in 1 byte (the descriptor)
606 // - Integers (intXXX, uintXXX) are encoded in 1, 2, 4 or 8 bytes (plus a descriptor byte).
607 // There are positive (uintXXX and intXXX >= 0) and negative (intXXX < 0) integers.
608 // - Floats are encoded in 4 or 8 bytes (plus a descriptor byte)
609 // - Length of containers (strings, bytes, array, map, extensions)
610 // are encoded in 0, 1, 2, 4 or 8 bytes.
611 // Zero-length containers have no length encoded.
612 // For others, the number of bytes is given by pow(2, bd%3)
613 // - maps are encoded as [bd] [length] [[key][value]]...
614 // - arrays are encoded as [bd] [length] [value]...
615 // - extensions are encoded as [bd] [length] [tag] [byte]...
616 // - strings/bytearrays are encoded as [bd] [length] [byte]...
617 // - time.Time are encoded as [bd] [length] [byte]...
619 // The full spec will be published soon.
620 type SimpleHandle struct {
624 // EncZeroValuesAsNil says to encode zero values for numbers, bool, string, etc as nil
625 EncZeroValuesAsNil bool
627 // _ [1]uint64 // padding
630 // Name returns the name of the handle: simple
631 func (h *SimpleHandle) Name() string { return "simple" }
633 // SetBytesExt sets an extension
634 func (h *SimpleHandle) SetBytesExt(rt reflect.Type, tag uint64, ext BytesExt) (err error) {
635 return h.SetExt(rt, tag, &extWrapper{ext, interfaceExtFailer{}})
638 func (h *SimpleHandle) hasElemSeparators() bool { return true } // as it implements Write(Map|Array)XXX
640 func (h *SimpleHandle) newEncDriver(e *Encoder) encDriver {
641 return &simpleEncDriver{e: e, w: e.w, h: h}
644 func (h *SimpleHandle) newDecDriver(d *Decoder) decDriver {
645 return &simpleDecDriver{d: d, h: h, r: d.r, br: d.bytes}
648 func (e *simpleEncDriver) reset() {
653 func (d *simpleDecDriver) reset() {
655 d.r, d.br = d.d.r, d.d.bytes
656 d.bd, d.bdRead = 0, false
659 var _ decDriver = (*simpleDecDriver)(nil)
660 var _ encDriver = (*simpleEncDriver)(nil)