// Copyright (c) 2012-2015 Ugorji Nwoke. All rights reserved. // Use of this source code is governed by a MIT license found in the LICENSE file. package codec import ( "bufio" "encoding" "fmt" "io" "reflect" "sort" "sync" "time" ) const defEncByteBufSize = 1 << 6 // 4:16, 6:64, 8:256, 10:1024 // AsSymbolFlag defines what should be encoded as symbols. type AsSymbolFlag uint8 const ( // AsSymbolDefault means only encode struct field names as symbols. AsSymbolDefault AsSymbolFlag = iota // AsSymbolAll means encode anything which could be a symbol as a symbol. AsSymbolAll = 0xfe // AsSymbolNone means do not encode anything as a symbol. AsSymbolNone = 1 << iota // AsSymbolMapStringKeysFlag means encode keys in map[string]XXX as symbols. AsSymbolMapStringKeysFlag // AsSymbolStructFieldNameFlag means encode struct field names as symbols. AsSymbolStructFieldNameFlag ) // encWriter abstracts writing to a byte array or to an io.Writer. type encWriter interface { writeb([]byte) writestr(string) writen1(byte) writen2(byte, byte) atEndOfEncode() } // encDriver abstracts the actual codec (binc vs msgpack, etc) type encDriver interface { // IsBuiltinType(rt uintptr) bool // Deprecated: left here for now so that old codecgen'ed filed will work. TODO: remove. EncodeBuiltin(rt uintptr, v interface{}) EncodeNil() EncodeInt(i int64) EncodeUint(i uint64) EncodeBool(b bool) EncodeFloat32(f float32) EncodeFloat64(f float64) // encodeExtPreamble(xtag byte, length int) EncodeRawExt(re *RawExt, e *Encoder) EncodeExt(v interface{}, xtag uint64, ext Ext, e *Encoder) WriteArrayStart(length int) WriteArrayElem() WriteArrayEnd() WriteMapStart(length int) WriteMapElemKey() WriteMapElemValue() WriteMapEnd() EncodeString(c charEncoding, v string) EncodeSymbol(v string) EncodeStringBytes(c charEncoding, v []byte) EncodeTime(time.Time) //TODO //encBignum(f *big.Int) //encStringRunes(c charEncoding, v []rune) reset() atEndOfEncode() } type ioEncStringWriter interface { WriteString(s string) (n int, err error) } type encDriverAsis interface { EncodeAsis(v []byte) } type encDriverNoopContainerWriter struct{} func (encDriverNoopContainerWriter) WriteArrayStart(length int) {} func (encDriverNoopContainerWriter) WriteArrayElem() {} func (encDriverNoopContainerWriter) WriteArrayEnd() {} func (encDriverNoopContainerWriter) WriteMapStart(length int) {} func (encDriverNoopContainerWriter) WriteMapElemKey() {} func (encDriverNoopContainerWriter) WriteMapElemValue() {} func (encDriverNoopContainerWriter) WriteMapEnd() {} func (encDriverNoopContainerWriter) atEndOfEncode() {} // type ioEncWriterWriter interface { // WriteByte(c byte) error // WriteString(s string) (n int, err error) // Write(p []byte) (n int, err error) // } // EncodeOptions captures configuration options during encode. type EncodeOptions struct { // Encode a struct as an array, and not as a map StructToArray bool // Canonical representation means that encoding a value will always result in the same // sequence of bytes. // // This only affects maps, as the iteration order for maps is random. // // The implementation MAY use the natural sort order for the map keys if possible: // // - If there is a natural sort order (ie for number, bool, string or []byte keys), // then the map keys are first sorted in natural order and then written // with corresponding map values to the strema. // - If there is no natural sort order, then the map keys will first be // encoded into []byte, and then sorted, // before writing the sorted keys and the corresponding map values to the stream. // Canonical bool // CheckCircularRef controls whether we check for circular references // and error fast during an encode. // // If enabled, an error is received if a pointer to a struct // references itself either directly or through one of its fields (iteratively). // // This is opt-in, as there may be a performance hit to checking circular references. CheckCircularRef bool // RecursiveEmptyCheck controls whether we descend into interfaces, structs and pointers // when checking if a value is empty. // // Note that this may make OmitEmpty more expensive, as it incurs a lot more reflect calls. RecursiveEmptyCheck bool // Raw controls whether we encode Raw values. // This is a "dangerous" option and must be explicitly set. // If set, we blindly encode Raw values as-is, without checking // if they are a correct representation of a value in that format. // If unset, we error out. Raw bool // AsSymbols defines what should be encoded as symbols. // // Encoding as symbols can reduce the encoded size significantly. // // However, during decoding, each string to be encoded as a symbol must // be checked to see if it has been seen before. Consequently, encoding time // will increase if using symbols, because string comparisons has a clear cost. // // Sample values: // AsSymbolNone // AsSymbolAll // AsSymbolMapStringKeys // AsSymbolMapStringKeysFlag | AsSymbolStructFieldNameFlag AsSymbols AsSymbolFlag // WriterBufferSize is the size of the buffer used when writing. // // if > 0, we use a smart buffer internally for performance purposes. WriterBufferSize int } // --------------------------------------------- type simpleIoEncWriter struct { io.Writer } // type bufIoEncWriter struct { // w io.Writer // buf []byte // err error // } // func (x *bufIoEncWriter) Write(b []byte) (n int, err error) { // if x.err != nil { // return 0, x.err // } // if cap(x.buf)-len(x.buf) >= len(b) { // x.buf = append(x.buf, b) // return len(b), nil // } // n, err = x.w.Write(x.buf) // if err != nil { // x.err = err // return 0, x.err // } // n, err = x.w.Write(b) // x.err = err // return // } // ioEncWriter implements encWriter and can write to an io.Writer implementation type ioEncWriter struct { w io.Writer ww io.Writer bw io.ByteWriter sw ioEncStringWriter fw ioFlusher b [8]byte } func (z *ioEncWriter) WriteByte(b byte) (err error) { // x.bs[0] = b // _, err = x.ww.Write(x.bs[:]) z.b[0] = b _, err = z.w.Write(z.b[:1]) return } func (z *ioEncWriter) WriteString(s string) (n int, err error) { return z.w.Write(bytesView(s)) } func (z *ioEncWriter) writeb(bs []byte) { // if len(bs) == 0 { // return // } if _, err := z.ww.Write(bs); err != nil { panic(err) } } func (z *ioEncWriter) writestr(s string) { // if len(s) == 0 { // return // } if _, err := z.sw.WriteString(s); err != nil { panic(err) } } func (z *ioEncWriter) writen1(b byte) { if err := z.bw.WriteByte(b); err != nil { panic(err) } } func (z *ioEncWriter) writen2(b1, b2 byte) { var err error if err = z.bw.WriteByte(b1); err == nil { if err = z.bw.WriteByte(b2); err == nil { return } } panic(err) } // func (z *ioEncWriter) writen5(b1, b2, b3, b4, b5 byte) { // z.b[0], z.b[1], z.b[2], z.b[3], z.b[4] = b1, b2, b3, b4, b5 // if _, err := z.ww.Write(z.b[:5]); err != nil { // panic(err) // } // } func (z *ioEncWriter) atEndOfEncode() { if z.fw != nil { z.fw.Flush() } } // ---------------------------------------- // bytesEncWriter implements encWriter and can write to an byte slice. // It is used by Marshal function. type bytesEncWriter struct { b []byte c int // cursor out *[]byte // write out on atEndOfEncode } func (z *bytesEncWriter) writeb(s []byte) { oc, a := z.growNoAlloc(len(s)) if a { z.growAlloc(len(s), oc) } copy(z.b[oc:], s) } func (z *bytesEncWriter) writestr(s string) { oc, a := z.growNoAlloc(len(s)) if a { z.growAlloc(len(s), oc) } copy(z.b[oc:], s) } func (z *bytesEncWriter) writen1(b1 byte) { oc, a := z.growNoAlloc(1) if a { z.growAlloc(1, oc) } z.b[oc] = b1 } func (z *bytesEncWriter) writen2(b1, b2 byte) { oc, a := z.growNoAlloc(2) if a { z.growAlloc(2, oc) } z.b[oc+1] = b2 z.b[oc] = b1 } func (z *bytesEncWriter) atEndOfEncode() { *(z.out) = z.b[:z.c] } // have a growNoalloc(n int), which can be inlined. // if allocation is needed, then call growAlloc(n int) func (z *bytesEncWriter) growNoAlloc(n int) (oldcursor int, allocNeeded bool) { oldcursor = z.c z.c = z.c + n if z.c > len(z.b) { if z.c > cap(z.b) { allocNeeded = true } else { z.b = z.b[:cap(z.b)] } } return } func (z *bytesEncWriter) growAlloc(n int, oldcursor int) { // appendslice logic (if cap < 1024, *2, else *1.25): more expensive. many copy calls. // bytes.Buffer model (2*cap + n): much better // bs := make([]byte, 2*cap(z.b)+n) bs := make([]byte, growCap(cap(z.b), 1, n)) copy(bs, z.b[:oldcursor]) z.b = bs } // --------------------------------------------- // func (e *Encoder) builtin(f *codecFnInfo, rv reflect.Value) { // e.e.EncodeBuiltin(f.ti.rtid, rv2i(rv)) // } func (e *Encoder) rawExt(f *codecFnInfo, rv reflect.Value) { // rev := rv2i(rv).(RawExt) // e.e.EncodeRawExt(&rev, e) // var re *RawExt // if rv.CanAddr() { // re = rv2i(rv.Addr()).(*RawExt) // } else { // rev := rv2i(rv).(RawExt) // re = &rev // } // e.e.EncodeRawExt(re, e) e.e.EncodeRawExt(rv2i(rv).(*RawExt), e) } func (e *Encoder) ext(f *codecFnInfo, rv reflect.Value) { // if this is a struct|array and it was addressable, then pass the address directly (not the value) // if k := rv.Kind(); (k == reflect.Struct || k == reflect.Array) && rv.CanAddr() { // rv = rv.Addr() // } e.e.EncodeExt(rv2i(rv), f.xfTag, f.xfFn, e) } // func rviptr(rv reflect.Value) (v interface{}) { // // If a non-pointer was passed to Encode(), then that value is not addressable. // // Take addr if addressable, else copy value to an addressable value. // if rv.CanAddr() { // v = rv2i(rv.Addr()) // } else { // rv2 := reflect.New(rv.Type()) // rv2.Elem().Set(rv) // v = rv2i(rv2) // } // return v // } func (e *Encoder) selferMarshal(f *codecFnInfo, rv reflect.Value) { rv2i(rv).(Selfer).CodecEncodeSelf(e) } func (e *Encoder) binaryMarshal(f *codecFnInfo, rv reflect.Value) { bs, fnerr := rv2i(rv).(encoding.BinaryMarshaler).MarshalBinary() e.marshal(bs, fnerr, false, cRAW) } func (e *Encoder) textMarshal(f *codecFnInfo, rv reflect.Value) { bs, fnerr := rv2i(rv).(encoding.TextMarshaler).MarshalText() e.marshal(bs, fnerr, false, cUTF8) } func (e *Encoder) jsonMarshal(f *codecFnInfo, rv reflect.Value) { bs, fnerr := rv2i(rv).(jsonMarshaler).MarshalJSON() e.marshal(bs, fnerr, true, cUTF8) } func (e *Encoder) raw(f *codecFnInfo, rv reflect.Value) { e.rawBytes(rv2i(rv).(Raw)) } func (e *Encoder) kInvalid(f *codecFnInfo, rv reflect.Value) { e.e.EncodeNil() } func (e *Encoder) kErr(f *codecFnInfo, rv reflect.Value) { e.errorf("unsupported kind %s, for %#v", rv.Kind(), rv) } func (e *Encoder) kSlice(f *codecFnInfo, rv reflect.Value) { ti := f.ti ee := e.e // array may be non-addressable, so we have to manage with care // (don't call rv.Bytes, rv.Slice, etc). // E.g. type struct S{B [2]byte}; // Encode(S{}) will bomb on "panic: slice of unaddressable array". if f.seq != seqTypeArray { if rv.IsNil() { ee.EncodeNil() return } // If in this method, then there was no extension function defined. // So it's okay to treat as []byte. if ti.rtid == uint8SliceTypId { ee.EncodeStringBytes(cRAW, rv.Bytes()) return } } if f.seq == seqTypeChan && ti.rt.ChanDir()&reflect.RecvDir == 0 { e.errorf("send-only channel cannot be used for receiving byte(s)") } elemsep := e.hh.hasElemSeparators() l := rv.Len() rtelem := ti.rt.Elem() rtelemIsByte := uint8TypId == rt2id(rtelem) // NOT rtelem.Kind() == reflect.Uint8 // if a slice, array or chan of bytes, treat specially if rtelemIsByte { switch f.seq { case seqTypeSlice: ee.EncodeStringBytes(cRAW, rv.Bytes()) case seqTypeArray: if rv.CanAddr() { ee.EncodeStringBytes(cRAW, rv.Slice(0, l).Bytes()) } else { var bs []byte if l <= cap(e.b) { bs = e.b[:l] } else { bs = make([]byte, l) } reflect.Copy(reflect.ValueOf(bs), rv) ee.EncodeStringBytes(cRAW, bs) } case seqTypeChan: bs := e.b[:0] // do not use range, so that the number of elements encoded // does not change, and encoding does not hang waiting on someone to close chan. // for b := range rv2i(rv).(<-chan byte) { bs = append(bs, b) } // ch := rv2i(rv).(<-chan byte) // fix error - that this is a chan byte, not a <-chan byte. irv := rv2i(rv) ch, ok := irv.(<-chan byte) if !ok { ch = irv.(chan byte) } for i := 0; i < l; i++ { bs = append(bs, <-ch) } ee.EncodeStringBytes(cRAW, bs) } return } if ti.mbs { if l%2 == 1 { e.errorf("mapBySlice requires even slice length, but got %v", l) return } ee.WriteMapStart(l / 2) } else { ee.WriteArrayStart(l) } if l > 0 { var fn *codecFn for rtelem.Kind() == reflect.Ptr { rtelem = rtelem.Elem() } // if kind is reflect.Interface, do not pre-determine the // encoding type, because preEncodeValue may break it down to // a concrete type and kInterface will bomb. if rtelem.Kind() != reflect.Interface { fn = e.cf.get(rtelem, true, true) } // TODO: Consider perf implication of encoding odd index values as symbols if type is string for j := 0; j < l; j++ { if elemsep { if ti.mbs { if j%2 == 0 { ee.WriteMapElemKey() } else { ee.WriteMapElemValue() } } else { ee.WriteArrayElem() } } if f.seq == seqTypeChan { if rv2, ok2 := rv.Recv(); ok2 { e.encodeValue(rv2, fn, true) } else { ee.EncodeNil() // WE HAVE TO DO SOMETHING, so nil if nothing received. } } else { e.encodeValue(rv.Index(j), fn, true) } } } if ti.mbs { ee.WriteMapEnd() } else { ee.WriteArrayEnd() } } func (e *Encoder) kStructNoOmitempty(f *codecFnInfo, rv reflect.Value) { fti := f.ti elemsep := e.hh.hasElemSeparators() tisfi := fti.sfip toMap := !(fti.toArray || e.h.StructToArray) if toMap { tisfi = fti.sfi } ee := e.e sfn := structFieldNode{v: rv, update: false} if toMap { ee.WriteMapStart(len(tisfi)) // asSymbols := e.h.AsSymbols&AsSymbolStructFieldNameFlag != 0 asSymbols := e.h.AsSymbols == AsSymbolDefault || e.h.AsSymbols&AsSymbolStructFieldNameFlag != 0 if !elemsep { for _, si := range tisfi { if asSymbols { ee.EncodeSymbol(si.encName) } else { ee.EncodeString(cUTF8, si.encName) } e.encodeValue(sfn.field(si), nil, true) } } else { for _, si := range tisfi { ee.WriteMapElemKey() if asSymbols { ee.EncodeSymbol(si.encName) } else { ee.EncodeString(cUTF8, si.encName) } ee.WriteMapElemValue() e.encodeValue(sfn.field(si), nil, true) } } ee.WriteMapEnd() } else { ee.WriteArrayStart(len(tisfi)) if !elemsep { for _, si := range tisfi { e.encodeValue(sfn.field(si), nil, true) } } else { for _, si := range tisfi { ee.WriteArrayElem() e.encodeValue(sfn.field(si), nil, true) } } ee.WriteArrayEnd() } } func (e *Encoder) kStruct(f *codecFnInfo, rv reflect.Value) { fti := f.ti elemsep := e.hh.hasElemSeparators() tisfi := fti.sfip toMap := !(fti.toArray || e.h.StructToArray) // if toMap, use the sorted array. If toArray, use unsorted array (to match sequence in struct) if toMap { tisfi = fti.sfi } newlen := len(fti.sfi) ee := e.e // Use sync.Pool to reduce allocating slices unnecessarily. // The cost of sync.Pool is less than the cost of new allocation. // // Each element of the array pools one of encStructPool(8|16|32|64). // It allows the re-use of slices up to 64 in length. // A performance cost of encoding structs was collecting // which values were empty and should be omitted. // We needed slices of reflect.Value and string to collect them. // This shared pool reduces the amount of unnecessary creation we do. // The cost is that of locking sometimes, but sync.Pool is efficient // enough to reduce thread contention. var spool *sync.Pool var poolv interface{} var fkvs []stringRv if newlen <= 8 { spool, poolv = pool.stringRv8() fkvs = poolv.(*[8]stringRv)[:newlen] } else if newlen <= 16 { spool, poolv = pool.stringRv16() fkvs = poolv.(*[16]stringRv)[:newlen] } else if newlen <= 32 { spool, poolv = pool.stringRv32() fkvs = poolv.(*[32]stringRv)[:newlen] } else if newlen <= 64 { spool, poolv = pool.stringRv64() fkvs = poolv.(*[64]stringRv)[:newlen] } else if newlen <= 128 { spool, poolv = pool.stringRv128() fkvs = poolv.(*[128]stringRv)[:newlen] } else { fkvs = make([]stringRv, newlen) } newlen = 0 var kv stringRv recur := e.h.RecursiveEmptyCheck sfn := structFieldNode{v: rv, update: false} for _, si := range tisfi { // kv.r = si.field(rv, false) kv.r = sfn.field(si) if toMap { if si.omitEmpty && isEmptyValue(kv.r, recur, recur) { continue } kv.v = si.encName } else { // use the zero value. // if a reference or struct, set to nil (so you do not output too much) if si.omitEmpty && isEmptyValue(kv.r, recur, recur) { switch kv.r.Kind() { case reflect.Struct, reflect.Interface, reflect.Ptr, reflect.Array, reflect.Map, reflect.Slice: kv.r = reflect.Value{} //encode as nil } } } fkvs[newlen] = kv newlen++ } if toMap { ee.WriteMapStart(newlen) // asSymbols := e.h.AsSymbols&AsSymbolStructFieldNameFlag != 0 asSymbols := e.h.AsSymbols == AsSymbolDefault || e.h.AsSymbols&AsSymbolStructFieldNameFlag != 0 if !elemsep { for j := 0; j < newlen; j++ { kv = fkvs[j] if asSymbols { ee.EncodeSymbol(kv.v) } else { ee.EncodeString(cUTF8, kv.v) } e.encodeValue(kv.r, nil, true) } } else { for j := 0; j < newlen; j++ { kv = fkvs[j] ee.WriteMapElemKey() if asSymbols { ee.EncodeSymbol(kv.v) } else { ee.EncodeString(cUTF8, kv.v) } ee.WriteMapElemValue() e.encodeValue(kv.r, nil, true) } } ee.WriteMapEnd() } else { ee.WriteArrayStart(newlen) if !elemsep { for j := 0; j < newlen; j++ { e.encodeValue(fkvs[j].r, nil, true) } } else { for j := 0; j < newlen; j++ { ee.WriteArrayElem() e.encodeValue(fkvs[j].r, nil, true) } } ee.WriteArrayEnd() } // do not use defer. Instead, use explicit pool return at end of function. // defer has a cost we are trying to avoid. // If there is a panic and these slices are not returned, it is ok. if spool != nil { spool.Put(poolv) } } func (e *Encoder) kMap(f *codecFnInfo, rv reflect.Value) { ee := e.e if rv.IsNil() { ee.EncodeNil() return } l := rv.Len() ee.WriteMapStart(l) elemsep := e.hh.hasElemSeparators() if l == 0 { ee.WriteMapEnd() return } var asSymbols bool // determine the underlying key and val encFn's for the map. // This eliminates some work which is done for each loop iteration i.e. // rv.Type(), ref.ValueOf(rt).Pointer(), then check map/list for fn. // // However, if kind is reflect.Interface, do not pre-determine the // encoding type, because preEncodeValue may break it down to // a concrete type and kInterface will bomb. var keyFn, valFn *codecFn ti := f.ti rtkey0 := ti.rt.Key() rtkey := rtkey0 rtval0 := ti.rt.Elem() rtval := rtval0 // rtkeyid := rt2id(rtkey0) for rtval.Kind() == reflect.Ptr { rtval = rtval.Elem() } if rtval.Kind() != reflect.Interface { valFn = e.cf.get(rtval, true, true) } mks := rv.MapKeys() if e.h.Canonical { e.kMapCanonical(rtkey, rv, mks, valFn, asSymbols) ee.WriteMapEnd() return } var keyTypeIsString = stringTypId == rt2id(rtkey0) // rtkeyid if keyTypeIsString { asSymbols = e.h.AsSymbols&AsSymbolMapStringKeysFlag != 0 } else { for rtkey.Kind() == reflect.Ptr { rtkey = rtkey.Elem() } if rtkey.Kind() != reflect.Interface { // rtkeyid = rt2id(rtkey) keyFn = e.cf.get(rtkey, true, true) } } // for j, lmks := 0, len(mks); j < lmks; j++ { for j := range mks { if elemsep { ee.WriteMapElemKey() } if keyTypeIsString { if asSymbols { ee.EncodeSymbol(mks[j].String()) } else { ee.EncodeString(cUTF8, mks[j].String()) } } else { e.encodeValue(mks[j], keyFn, true) } if elemsep { ee.WriteMapElemValue() } e.encodeValue(rv.MapIndex(mks[j]), valFn, true) } ee.WriteMapEnd() } func (e *Encoder) kMapCanonical(rtkey reflect.Type, rv reflect.Value, mks []reflect.Value, valFn *codecFn, asSymbols bool) { ee := e.e elemsep := e.hh.hasElemSeparators() // we previously did out-of-band if an extension was registered. // This is not necessary, as the natural kind is sufficient for ordering. // WHAT IS THIS? rtkeyid can never be a []uint8, per spec // if rtkeyid == uint8SliceTypId { // mksv := make([]bytesRv, len(mks)) // for i, k := range mks { // v := &mksv[i] // v.r = k // v.v = k.Bytes() // } // sort.Sort(bytesRvSlice(mksv)) // for i := range mksv { // if elemsep { // ee.WriteMapElemKey() // } // ee.EncodeStringBytes(cRAW, mksv[i].v) // if elemsep { // ee.WriteMapElemValue() // } // e.encodeValue(rv.MapIndex(mksv[i].r), valFn, true) // } // return // } switch rtkey.Kind() { case reflect.Bool: mksv := make([]boolRv, len(mks)) for i, k := range mks { v := &mksv[i] v.r = k v.v = k.Bool() } sort.Sort(boolRvSlice(mksv)) for i := range mksv { if elemsep { ee.WriteMapElemKey() } ee.EncodeBool(mksv[i].v) if elemsep { ee.WriteMapElemValue() } e.encodeValue(rv.MapIndex(mksv[i].r), valFn, true) } case reflect.String: mksv := make([]stringRv, len(mks)) for i, k := range mks { v := &mksv[i] v.r = k v.v = k.String() } sort.Sort(stringRvSlice(mksv)) for i := range mksv { if elemsep { ee.WriteMapElemKey() } if asSymbols { ee.EncodeSymbol(mksv[i].v) } else { ee.EncodeString(cUTF8, mksv[i].v) } if elemsep { ee.WriteMapElemValue() } e.encodeValue(rv.MapIndex(mksv[i].r), valFn, true) } case reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uint, reflect.Uintptr: mksv := make([]uintRv, len(mks)) for i, k := range mks { v := &mksv[i] v.r = k v.v = k.Uint() } sort.Sort(uintRvSlice(mksv)) for i := range mksv { if elemsep { ee.WriteMapElemKey() } ee.EncodeUint(mksv[i].v) if elemsep { ee.WriteMapElemValue() } e.encodeValue(rv.MapIndex(mksv[i].r), valFn, true) } case reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64, reflect.Int: mksv := make([]intRv, len(mks)) for i, k := range mks { v := &mksv[i] v.r = k v.v = k.Int() } sort.Sort(intRvSlice(mksv)) for i := range mksv { if elemsep { ee.WriteMapElemKey() } ee.EncodeInt(mksv[i].v) if elemsep { ee.WriteMapElemValue() } e.encodeValue(rv.MapIndex(mksv[i].r), valFn, true) } case reflect.Float32: mksv := make([]floatRv, len(mks)) for i, k := range mks { v := &mksv[i] v.r = k v.v = k.Float() } sort.Sort(floatRvSlice(mksv)) for i := range mksv { if elemsep { ee.WriteMapElemKey() } ee.EncodeFloat32(float32(mksv[i].v)) if elemsep { ee.WriteMapElemValue() } e.encodeValue(rv.MapIndex(mksv[i].r), valFn, true) } case reflect.Float64: mksv := make([]floatRv, len(mks)) for i, k := range mks { v := &mksv[i] v.r = k v.v = k.Float() } sort.Sort(floatRvSlice(mksv)) for i := range mksv { if elemsep { ee.WriteMapElemKey() } ee.EncodeFloat64(mksv[i].v) if elemsep { ee.WriteMapElemValue() } e.encodeValue(rv.MapIndex(mksv[i].r), valFn, true) } case reflect.Struct: if rv.Type() == timeTyp { mksv := make([]timeRv, len(mks)) for i, k := range mks { v := &mksv[i] v.r = k v.v = rv2i(k).(time.Time) } sort.Sort(timeRvSlice(mksv)) for i := range mksv { if elemsep { ee.WriteMapElemKey() } ee.EncodeTime(mksv[i].v) if elemsep { ee.WriteMapElemValue() } e.encodeValue(rv.MapIndex(mksv[i].r), valFn, true) } break } fallthrough default: // out-of-band // first encode each key to a []byte first, then sort them, then record var mksv []byte = make([]byte, 0, len(mks)*16) // temporary byte slice for the encoding e2 := NewEncoderBytes(&mksv, e.hh) mksbv := make([]bytesRv, len(mks)) for i, k := range mks { v := &mksbv[i] l := len(mksv) e2.MustEncode(k) v.r = k v.v = mksv[l:] } sort.Sort(bytesRvSlice(mksbv)) for j := range mksbv { if elemsep { ee.WriteMapElemKey() } e.asis(mksbv[j].v) if elemsep { ee.WriteMapElemValue() } e.encodeValue(rv.MapIndex(mksbv[j].r), valFn, true) } } } // // -------------------------------------------------- // An Encoder writes an object to an output stream in the codec format. type Encoder struct { // hopefully, reduce derefencing cost by laying the encWriter inside the Encoder e encDriver // NOTE: Encoder shouldn't call it's write methods, // as the handler MAY need to do some coordination. w encWriter hh Handle h *BasicHandle // ---- cpu cache line boundary? wi ioEncWriter wb bytesEncWriter bw bufio.Writer // cr containerStateRecv as encDriverAsis // ---- cpu cache line boundary? ci set err error b [scratchByteArrayLen]byte cf codecFner } // NewEncoder returns an Encoder for encoding into an io.Writer. // // For efficiency, Users are encouraged to pass in a memory buffered writer // (eg bufio.Writer, bytes.Buffer). func NewEncoder(w io.Writer, h Handle) *Encoder { e := newEncoder(h) e.Reset(w) return e } // NewEncoderBytes returns an encoder for encoding directly and efficiently // into a byte slice, using zero-copying to temporary slices. // // It will potentially replace the output byte slice pointed to. // After encoding, the out parameter contains the encoded contents. func NewEncoderBytes(out *[]byte, h Handle) *Encoder { e := newEncoder(h) e.ResetBytes(out) return e } func newEncoder(h Handle) *Encoder { e := &Encoder{hh: h, h: h.getBasicHandle()} e.e = h.newEncDriver(e) e.as, _ = e.e.(encDriverAsis) // e.cr, _ = e.e.(containerStateRecv) return e } // Reset resets the Encoder with a new output stream. // // This accommodates using the state of the Encoder, // where it has "cached" information about sub-engines. func (e *Encoder) Reset(w io.Writer) { var ok bool e.wi.w = w if e.h.WriterBufferSize > 0 { bw := bufio.NewWriterSize(w, e.h.WriterBufferSize) e.bw = *bw e.wi.bw = &e.bw e.wi.sw = &e.bw e.wi.fw = &e.bw e.wi.ww = &e.bw } else { if e.wi.bw, ok = w.(io.ByteWriter); !ok { e.wi.bw = &e.wi } if e.wi.sw, ok = w.(ioEncStringWriter); !ok { e.wi.sw = &e.wi } e.wi.fw, _ = w.(ioFlusher) e.wi.ww = w } e.w = &e.wi e.e.reset() e.cf.reset(e.hh) e.err = nil } // ResetBytes resets the Encoder with a new destination output []byte. func (e *Encoder) ResetBytes(out *[]byte) { in := *out if in == nil { in = make([]byte, defEncByteBufSize) } e.wb.b, e.wb.out, e.wb.c = in, out, 0 e.w = &e.wb e.e.reset() e.cf.reset(e.hh) e.err = nil } // Encode writes an object into a stream. // // Encoding can be configured via the struct tag for the fields. // The "codec" key in struct field's tag value is the key name, // followed by an optional comma and options. // Note that the "json" key is used in the absence of the "codec" key. // // To set an option on all fields (e.g. omitempty on all fields), you // can create a field called _struct, and set flags on it. // // Struct values "usually" encode as maps. Each exported struct field is encoded unless: // - the field's tag is "-", OR // - the field is empty (empty or the zero value) and its tag specifies the "omitempty" option. // // When encoding as a map, the first string in the tag (before the comma) // is the map key string to use when encoding. // // However, struct values may encode as arrays. This happens when: // - StructToArray Encode option is set, OR // - the tag on the _struct field sets the "toarray" option // Note that omitempty is ignored when encoding struct values as arrays, // as an entry must be encoded for each field, to maintain its position. // // Values with types that implement MapBySlice are encoded as stream maps. // // The empty values (for omitempty option) are false, 0, any nil pointer // or interface value, and any array, slice, map, or string of length zero. // // Anonymous fields are encoded inline except: // - the struct tag specifies a replacement name (first value) // - the field is of an interface type // // Examples: // // // NOTE: 'json:' can be used as struct tag key, in place 'codec:' below. // type MyStruct struct { // _struct bool `codec:",omitempty"` //set omitempty for every field // Field1 string `codec:"-"` //skip this field // Field2 int `codec:"myName"` //Use key "myName" in encode stream // Field3 int32 `codec:",omitempty"` //use key "Field3". Omit if empty. // Field4 bool `codec:"f4,omitempty"` //use key "f4". Omit if empty. // io.Reader //use key "Reader". // MyStruct `codec:"my1" //use key "my1". // MyStruct //inline it // ... // } // // type MyStruct struct { // _struct bool `codec:",toarray"` //encode struct as an array // } // // The mode of encoding is based on the type of the value. When a value is seen: // - If a Selfer, call its CodecEncodeSelf method // - If an extension is registered for it, call that extension function // - If it implements encoding.(Binary|Text|JSON)Marshaler, call its Marshal(Binary|Text|JSON) method // - Else encode it based on its reflect.Kind // // Note that struct field names and keys in map[string]XXX will be treated as symbols. // Some formats support symbols (e.g. binc) and will properly encode the string // only once in the stream, and use a tag to refer to it thereafter. func (e *Encoder) Encode(v interface{}) (err error) { defer panicToErrs2(&e.err, &err) e.MustEncode(v) return } // MustEncode is like Encode, but panics if unable to Encode. // This provides insight to the code location that triggered the error. func (e *Encoder) MustEncode(v interface{}) { if e.err != nil { panic(e.err) } e.encode(v) e.e.atEndOfEncode() e.w.atEndOfEncode() } func (e *Encoder) encode(iv interface{}) { if iv == nil || definitelyNil(iv) { e.e.EncodeNil() return } if v, ok := iv.(Selfer); ok { v.CodecEncodeSelf(e) return } switch v := iv.(type) { // case nil: // e.e.EncodeNil() // case Selfer: // v.CodecEncodeSelf(e) case Raw: e.rawBytes(v) case reflect.Value: e.encodeValue(v, nil, true) case string: e.e.EncodeString(cUTF8, v) case bool: e.e.EncodeBool(v) case int: e.e.EncodeInt(int64(v)) case int8: e.e.EncodeInt(int64(v)) case int16: e.e.EncodeInt(int64(v)) case int32: e.e.EncodeInt(int64(v)) case int64: e.e.EncodeInt(v) case uint: e.e.EncodeUint(uint64(v)) case uint8: e.e.EncodeUint(uint64(v)) case uint16: e.e.EncodeUint(uint64(v)) case uint32: e.e.EncodeUint(uint64(v)) case uint64: e.e.EncodeUint(v) case uintptr: e.e.EncodeUint(uint64(v)) case float32: e.e.EncodeFloat32(v) case float64: e.e.EncodeFloat64(v) case time.Time: e.e.EncodeTime(v) case []uint8: e.e.EncodeStringBytes(cRAW, v) case *Raw: e.rawBytes(*v) case *string: e.e.EncodeString(cUTF8, *v) case *bool: e.e.EncodeBool(*v) case *int: e.e.EncodeInt(int64(*v)) case *int8: e.e.EncodeInt(int64(*v)) case *int16: e.e.EncodeInt(int64(*v)) case *int32: e.e.EncodeInt(int64(*v)) case *int64: e.e.EncodeInt(*v) case *uint: e.e.EncodeUint(uint64(*v)) case *uint8: e.e.EncodeUint(uint64(*v)) case *uint16: e.e.EncodeUint(uint64(*v)) case *uint32: e.e.EncodeUint(uint64(*v)) case *uint64: e.e.EncodeUint(*v) case *uintptr: e.e.EncodeUint(uint64(*v)) case *float32: e.e.EncodeFloat32(*v) case *float64: e.e.EncodeFloat64(*v) case *time.Time: e.e.EncodeTime(*v) case *[]uint8: e.e.EncodeStringBytes(cRAW, *v) default: if !fastpathEncodeTypeSwitch(iv, e) { // checkfastpath=true (not false), as underlying slice/map type may be fast-path e.encodeValue(reflect.ValueOf(iv), nil, true) } } } func (e *Encoder) encodeValue(rv reflect.Value, fn *codecFn, checkFastpath bool) { // if a valid fn is passed, it MUST BE for the dereferenced type of rv var sptr uintptr var rvp reflect.Value var rvpValid bool TOP: switch rv.Kind() { case reflect.Ptr: if rv.IsNil() { e.e.EncodeNil() return } rvpValid = true rvp = rv rv = rv.Elem() if e.h.CheckCircularRef && rv.Kind() == reflect.Struct { // TODO: Movable pointers will be an issue here. Future problem. sptr = rv.UnsafeAddr() break TOP } goto TOP case reflect.Interface: if rv.IsNil() { e.e.EncodeNil() return } rv = rv.Elem() goto TOP case reflect.Slice, reflect.Map: if rv.IsNil() { e.e.EncodeNil() return } case reflect.Invalid, reflect.Func: e.e.EncodeNil() return } if sptr != 0 && (&e.ci).add(sptr) { e.errorf("circular reference found: # %d", sptr) } if fn == nil { rt := rv.Type() // always pass checkCodecSelfer=true, in case T or ****T is passed, where *T is a Selfer fn = e.cf.get(rt, checkFastpath, true) } if fn.i.addrE { if rvpValid { fn.fe(e, &fn.i, rvp) } else if rv.CanAddr() { fn.fe(e, &fn.i, rv.Addr()) } else { rv2 := reflect.New(rv.Type()) rv2.Elem().Set(rv) fn.fe(e, &fn.i, rv2) } } else { fn.fe(e, &fn.i, rv) } if sptr != 0 { (&e.ci).remove(sptr) } } func (e *Encoder) marshal(bs []byte, fnerr error, asis bool, c charEncoding) { if fnerr != nil { panic(fnerr) } if bs == nil { e.e.EncodeNil() } else if asis { e.asis(bs) } else { e.e.EncodeStringBytes(c, bs) } } func (e *Encoder) asis(v []byte) { if e.as == nil { e.w.writeb(v) } else { e.as.EncodeAsis(v) } } func (e *Encoder) rawBytes(vv Raw) { v := []byte(vv) if !e.h.Raw { e.errorf("Raw values cannot be encoded: %v", v) } if e.as == nil { e.w.writeb(v) } else { e.as.EncodeAsis(v) } } func (e *Encoder) errorf(format string, params ...interface{}) { err := fmt.Errorf(format, params...) panic(err) } func (e *Encoder) error(err error) { panic(err) }