// 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 // Contains code shared by both encode and decode. // Some shared ideas around encoding/decoding // ------------------------------------------ // // If an interface{} is passed, we first do a type assertion to see if it is // a primitive type or a map/slice of primitive types, and use a fastpath to handle it. // // If we start with a reflect.Value, we are already in reflect.Value land and // will try to grab the function for the underlying Type and directly call that function. // This is more performant than calling reflect.Value.Interface(). // // This still helps us bypass many layers of reflection, and give best performance. // // Containers // ------------ // Containers in the stream are either associative arrays (key-value pairs) or // regular arrays (indexed by incrementing integers). // // Some streams support indefinite-length containers, and use a breaking // byte-sequence to denote that the container has come to an end. // // Some streams also are text-based, and use explicit separators to denote the // end/beginning of different values. // // During encode, we use a high-level condition to determine how to iterate through // the container. That decision is based on whether the container is text-based (with // separators) or binary (without separators). If binary, we do not even call the // encoding of separators. // // During decode, we use a different high-level condition to determine how to iterate // through the containers. That decision is based on whether the stream contained // a length prefix, or if it used explicit breaks. If length-prefixed, we assume that // it has to be binary, and we do not even try to read separators. // // Philosophy // ------------ // On decode, this codec will update containers appropriately: // - If struct, update fields from stream into fields of struct. // If field in stream not found in struct, handle appropriately (based on option). // If a struct field has no corresponding value in the stream, leave it AS IS. // If nil in stream, set value to nil/zero value. // - If map, update map from stream. // If the stream value is NIL, set the map to nil. // - if slice, try to update up to length of array in stream. // if container len is less than stream array length, // and container cannot be expanded, handled (based on option). // This means you can decode 4-element stream array into 1-element array. // // ------------------------------------ // On encode, user can specify omitEmpty. This means that the value will be omitted // if the zero value. The problem may occur during decode, where omitted values do not affect // the value being decoded into. This means that if decoding into a struct with an // int field with current value=5, and the field is omitted in the stream, then after // decoding, the value will still be 5 (not 0). // omitEmpty only works if you guarantee that you always decode into zero-values. // // ------------------------------------ // We could have truncated a map to remove keys not available in the stream, // or set values in the struct which are not in the stream to their zero values. // We decided against it because there is no efficient way to do it. // We may introduce it as an option later. // However, that will require enabling it for both runtime and code generation modes. // // To support truncate, we need to do 2 passes over the container: // map // - first collect all keys (e.g. in k1) // - for each key in stream, mark k1 that the key should not be removed // - after updating map, do second pass and call delete for all keys in k1 which are not marked // struct: // - for each field, track the *typeInfo s1 // - iterate through all s1, and for each one not marked, set value to zero // - this involves checking the possible anonymous fields which are nil ptrs. // too much work. // // ------------------------------------------ // Error Handling is done within the library using panic. // // This way, the code doesn't have to keep checking if an error has happened, // and we don't have to keep sending the error value along with each call // or storing it in the En|Decoder and checking it constantly along the way. // // The disadvantage is that small functions which use panics cannot be inlined. // The code accounts for that by only using panics behind an interface; // since interface calls cannot be inlined, this is irrelevant. // // We considered storing the error is En|Decoder. // - once it has its err field set, it cannot be used again. // - panicing will be optional, controlled by const flag. // - code should always check error first and return early. // We eventually decided against it as it makes the code clumsier to always // check for these error conditions. import ( "bytes" "encoding" "encoding/binary" "errors" "fmt" "io" "math" "reflect" "sort" "strconv" "strings" "sync" "sync/atomic" "time" ) const ( scratchByteArrayLen = 32 // initCollectionCap = 16 // 32 is defensive. 16 is preferred. // Support encoding.(Binary|Text)(Unm|M)arshaler. // This constant flag will enable or disable it. supportMarshalInterfaces = true // for debugging, set this to false, to catch panic traces. // Note that this will always cause rpc tests to fail, since they need io.EOF sent via panic. recoverPanicToErr = true // arrayCacheLen is the length of the cache used in encoder or decoder for // allowing zero-alloc initialization. arrayCacheLen = 8 // size of the cacheline: defaulting to value for archs: amd64, arm64, 386 // should use "runtime/internal/sys".CacheLineSize, but that is not exposed. cacheLineSize = 64 wordSizeBits = 32 << (^uint(0) >> 63) // strconv.IntSize wordSize = wordSizeBits / 8 // so structFieldInfo fits into 8 bytes maxLevelsEmbedding = 14 // useFinalizers=true configures finalizers to release pool'ed resources // acquired by Encoder/Decoder during their GC. // // Note that calling SetFinalizer is always expensive, // as code must be run on the systemstack even for SetFinalizer(t, nil). // // We document that folks SHOULD call Release() when done, or they can // explicitly call SetFinalizer themselves e.g. // runtime.SetFinalizer(e, (*Encoder).Release) // runtime.SetFinalizer(d, (*Decoder).Release) useFinalizers = false removeFinalizerOnRelease = false ) var oneByteArr [1]byte var zeroByteSlice = oneByteArr[:0:0] var codecgen bool var refBitset bitset256 var pool pooler var panicv panicHdl func init() { pool.init() refBitset.set(byte(reflect.Map)) refBitset.set(byte(reflect.Ptr)) refBitset.set(byte(reflect.Func)) refBitset.set(byte(reflect.Chan)) } type clsErr struct { closed bool // is it closed? errClosed error // error on closing } // type entryType uint8 // const ( // entryTypeBytes entryType = iota // make this 0, so a comparison is cheap // entryTypeIo // entryTypeBufio // entryTypeUnset = 255 // ) type charEncoding uint8 const ( _ charEncoding = iota // make 0 unset cUTF8 cUTF16LE cUTF16BE cUTF32LE cUTF32BE // Deprecated: not a true char encoding value cRAW charEncoding = 255 ) // valueType is the stream type type valueType uint8 const ( valueTypeUnset valueType = iota valueTypeNil valueTypeInt valueTypeUint valueTypeFloat valueTypeBool valueTypeString valueTypeSymbol valueTypeBytes valueTypeMap valueTypeArray valueTypeTime valueTypeExt // valueTypeInvalid = 0xff ) var valueTypeStrings = [...]string{ "Unset", "Nil", "Int", "Uint", "Float", "Bool", "String", "Symbol", "Bytes", "Map", "Array", "Timestamp", "Ext", } func (x valueType) String() string { if int(x) < len(valueTypeStrings) { return valueTypeStrings[x] } return strconv.FormatInt(int64(x), 10) } type seqType uint8 const ( _ seqType = iota seqTypeArray seqTypeSlice seqTypeChan ) // note that containerMapStart and containerArraySend are not sent. // This is because the ReadXXXStart and EncodeXXXStart already does these. type containerState uint8 const ( _ containerState = iota containerMapStart // slot left open, since Driver method already covers it containerMapKey containerMapValue containerMapEnd containerArrayStart // slot left open, since Driver methods already cover it containerArrayElem containerArrayEnd ) // // sfiIdx used for tracking where a (field/enc)Name is seen in a []*structFieldInfo // type sfiIdx struct { // name string // index int // } // do not recurse if a containing type refers to an embedded type // which refers back to its containing type (via a pointer). // The second time this back-reference happens, break out, // so as not to cause an infinite loop. const rgetMaxRecursion = 2 // Anecdotally, we believe most types have <= 12 fields. // - even Java's PMD rules set TooManyFields threshold to 15. // However, go has embedded fields, which should be regarded as // top level, allowing structs to possibly double or triple. // In addition, we don't want to keep creating transient arrays, // especially for the sfi index tracking, and the evtypes tracking. // // So - try to keep typeInfoLoadArray within 2K bytes const ( typeInfoLoadArraySfisLen = 16 typeInfoLoadArraySfiidxLen = 8 * 112 typeInfoLoadArrayEtypesLen = 12 typeInfoLoadArrayBLen = 8 * 4 ) type typeInfoLoad struct { // fNames []string // encNames []string etypes []uintptr sfis []structFieldInfo } type typeInfoLoadArray struct { // fNames [typeInfoLoadArrayLen]string // encNames [typeInfoLoadArrayLen]string sfis [typeInfoLoadArraySfisLen]structFieldInfo sfiidx [typeInfoLoadArraySfiidxLen]byte etypes [typeInfoLoadArrayEtypesLen]uintptr b [typeInfoLoadArrayBLen]byte // scratch - used for struct field names } // mirror json.Marshaler and json.Unmarshaler here, // so we don't import the encoding/json package type jsonMarshaler interface { MarshalJSON() ([]byte, error) } type jsonUnmarshaler interface { UnmarshalJSON([]byte) error } type isZeroer interface { IsZero() bool } type codecError struct { name string err interface{} } func (e codecError) Cause() error { switch xerr := e.err.(type) { case nil: return nil case error: return xerr case string: return errors.New(xerr) case fmt.Stringer: return errors.New(xerr.String()) default: return fmt.Errorf("%v", e.err) } } func (e codecError) Error() string { return fmt.Sprintf("%s error: %v", e.name, e.err) } // type byteAccepter func(byte) bool var ( bigen = binary.BigEndian structInfoFieldName = "_struct" mapStrIntfTyp = reflect.TypeOf(map[string]interface{}(nil)) mapIntfIntfTyp = reflect.TypeOf(map[interface{}]interface{}(nil)) intfSliceTyp = reflect.TypeOf([]interface{}(nil)) intfTyp = intfSliceTyp.Elem() reflectValTyp = reflect.TypeOf((*reflect.Value)(nil)).Elem() stringTyp = reflect.TypeOf("") timeTyp = reflect.TypeOf(time.Time{}) rawExtTyp = reflect.TypeOf(RawExt{}) rawTyp = reflect.TypeOf(Raw{}) uintptrTyp = reflect.TypeOf(uintptr(0)) uint8Typ = reflect.TypeOf(uint8(0)) uint8SliceTyp = reflect.TypeOf([]uint8(nil)) uintTyp = reflect.TypeOf(uint(0)) intTyp = reflect.TypeOf(int(0)) mapBySliceTyp = reflect.TypeOf((*MapBySlice)(nil)).Elem() binaryMarshalerTyp = reflect.TypeOf((*encoding.BinaryMarshaler)(nil)).Elem() binaryUnmarshalerTyp = reflect.TypeOf((*encoding.BinaryUnmarshaler)(nil)).Elem() textMarshalerTyp = reflect.TypeOf((*encoding.TextMarshaler)(nil)).Elem() textUnmarshalerTyp = reflect.TypeOf((*encoding.TextUnmarshaler)(nil)).Elem() jsonMarshalerTyp = reflect.TypeOf((*jsonMarshaler)(nil)).Elem() jsonUnmarshalerTyp = reflect.TypeOf((*jsonUnmarshaler)(nil)).Elem() selferTyp = reflect.TypeOf((*Selfer)(nil)).Elem() missingFielderTyp = reflect.TypeOf((*MissingFielder)(nil)).Elem() iszeroTyp = reflect.TypeOf((*isZeroer)(nil)).Elem() uint8TypId = rt2id(uint8Typ) uint8SliceTypId = rt2id(uint8SliceTyp) rawExtTypId = rt2id(rawExtTyp) rawTypId = rt2id(rawTyp) intfTypId = rt2id(intfTyp) timeTypId = rt2id(timeTyp) stringTypId = rt2id(stringTyp) mapStrIntfTypId = rt2id(mapStrIntfTyp) mapIntfIntfTypId = rt2id(mapIntfIntfTyp) intfSliceTypId = rt2id(intfSliceTyp) // mapBySliceTypId = rt2id(mapBySliceTyp) intBitsize = uint8(intTyp.Bits()) uintBitsize = uint8(uintTyp.Bits()) // bsAll0x00 = []byte{0, 0, 0, 0, 0, 0, 0, 0} bsAll0xff = []byte{0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff} chkOvf checkOverflow errNoFieldNameToStructFieldInfo = errors.New("no field name passed to parseStructFieldInfo") ) var defTypeInfos = NewTypeInfos([]string{"codec", "json"}) var immutableKindsSet = [32]bool{ // reflect.Invalid: , reflect.Bool: true, reflect.Int: true, reflect.Int8: true, reflect.Int16: true, reflect.Int32: true, reflect.Int64: true, reflect.Uint: true, reflect.Uint8: true, reflect.Uint16: true, reflect.Uint32: true, reflect.Uint64: true, reflect.Uintptr: true, reflect.Float32: true, reflect.Float64: true, reflect.Complex64: true, reflect.Complex128: true, // reflect.Array // reflect.Chan // reflect.Func: true, // reflect.Interface // reflect.Map // reflect.Ptr // reflect.Slice reflect.String: true, // reflect.Struct // reflect.UnsafePointer } // Selfer defines methods by which a value can encode or decode itself. // // Any type which implements Selfer will be able to encode or decode itself. // Consequently, during (en|de)code, this takes precedence over // (text|binary)(M|Unm)arshal or extension support. // // By definition, it is not allowed for a Selfer to directly call Encode or Decode on itself. // If that is done, Encode/Decode will rightfully fail with a Stack Overflow style error. // For example, the snippet below will cause such an error. // type testSelferRecur struct{} // func (s *testSelferRecur) CodecEncodeSelf(e *Encoder) { e.MustEncode(s) } // func (s *testSelferRecur) CodecDecodeSelf(d *Decoder) { d.MustDecode(s) } // // Note: *the first set of bytes of any value MUST NOT represent nil in the format*. // This is because, during each decode, we first check the the next set of bytes // represent nil, and if so, we just set the value to nil. type Selfer interface { CodecEncodeSelf(*Encoder) CodecDecodeSelf(*Decoder) } // MissingFielder defines the interface allowing structs to internally decode or encode // values which do not map to struct fields. // // We expect that this interface is bound to a pointer type (so the mutation function works). // // A use-case is if a version of a type unexports a field, but you want compatibility between // both versions during encoding and decoding. // // Note that the interface is completely ignored during codecgen. type MissingFielder interface { // CodecMissingField is called to set a missing field and value pair. // // It returns true if the missing field was set on the struct. CodecMissingField(field []byte, value interface{}) bool // CodecMissingFields returns the set of fields which are not struct fields CodecMissingFields() map[string]interface{} } // MapBySlice is a tag interface that denotes wrapped slice should encode as a map in the stream. // The slice contains a sequence of key-value pairs. // This affords storing a map in a specific sequence in the stream. // // Example usage: // type T1 []string // or []int or []Point or any other "slice" type // func (_ T1) MapBySlice{} // T1 now implements MapBySlice, and will be encoded as a map // type T2 struct { KeyValues T1 } // // var kvs = []string{"one", "1", "two", "2", "three", "3"} // var v2 = T2{ KeyValues: T1(kvs) } // // v2 will be encoded like the map: {"KeyValues": {"one": "1", "two": "2", "three": "3"} } // // The support of MapBySlice affords the following: // - A slice type which implements MapBySlice will be encoded as a map // - A slice can be decoded from a map in the stream // - It MUST be a slice type (not a pointer receiver) that implements MapBySlice type MapBySlice interface { MapBySlice() } // BasicHandle encapsulates the common options and extension functions. // // Deprecated: DO NOT USE DIRECTLY. EXPORTED FOR GODOC BENEFIT. WILL BE REMOVED. type BasicHandle struct { // BasicHandle is always a part of a different type. // It doesn't have to fit into it own cache lines. // TypeInfos is used to get the type info for any type. // // If not configured, the default TypeInfos is used, which uses struct tag keys: codec, json TypeInfos *TypeInfos // Note: BasicHandle is not comparable, due to these slices here (extHandle, intf2impls). // If *[]T is used instead, this becomes comparable, at the cost of extra indirection. // Thses slices are used all the time, so keep as slices (not pointers). extHandle intf2impls inited uint32 _ uint32 // padding // ---- cache line RPCOptions // TimeNotBuiltin configures whether time.Time should be treated as a builtin type. // // All Handlers should know how to encode/decode time.Time as part of the core // format specification, or as a standard extension defined by the format. // // However, users can elect to handle time.Time as a custom extension, or via the // standard library's encoding.Binary(M|Unm)arshaler or Text(M|Unm)arshaler interface. // To elect this behavior, users can set TimeNotBuiltin=true. // Note: Setting TimeNotBuiltin=true can be used to enable the legacy behavior // (for Cbor and Msgpack), where time.Time was not a builtin supported type. TimeNotBuiltin bool // ExplicitRelease configures whether Release() is implicitly called after an encode or // decode call. // // If you will hold onto an Encoder or Decoder for re-use, by calling Reset(...) // on it or calling (Must)Encode repeatedly into a given []byte or io.Writer, // then you do not want it to be implicitly closed after each Encode/Decode call. // Doing so will unnecessarily return resources to the shared pool, only for you to // grab them right after again to do another Encode/Decode call. // // Instead, you configure ExplicitRelease=true, and you explicitly call Release() when // you are truly done. // // As an alternative, you can explicitly set a finalizer - so its resources // are returned to the shared pool before it is garbage-collected. Do it as below: // runtime.SetFinalizer(e, (*Encoder).Release) // runtime.SetFinalizer(d, (*Decoder).Release) ExplicitRelease bool be bool // is handle a binary encoding? js bool // is handle javascript handler? n byte // first letter of handle name _ uint16 // padding // ---- cache line DecodeOptions // ---- cache line EncodeOptions // noBuiltInTypeChecker rtidFns atomicRtidFnSlice mu sync.Mutex // r []uintptr // rtids mapped to s above } // basicHandle returns an initialized BasicHandle from the Handle. func basicHandle(hh Handle) (x *BasicHandle) { x = hh.getBasicHandle() if atomic.CompareAndSwapUint32(&x.inited, 0, 1) { x.be = hh.isBinary() _, x.js = hh.(*JsonHandle) x.n = hh.Name()[0] } return } func (x *BasicHandle) getBasicHandle() *BasicHandle { return x } func (x *BasicHandle) getTypeInfo(rtid uintptr, rt reflect.Type) (pti *typeInfo) { if x.TypeInfos == nil { return defTypeInfos.get(rtid, rt) } return x.TypeInfos.get(rtid, rt) } func findFn(s []codecRtidFn, rtid uintptr) (i uint, fn *codecFn) { // binary search. adapted from sort/search.go. // Note: we use goto (instead of for loop) so this can be inlined. // h, i, j := 0, 0, len(s) var h uint // var h, i uint var j = uint(len(s)) LOOP: if i < j { h = i + (j-i)/2 if s[h].rtid < rtid { i = h + 1 } else { j = h } goto LOOP } if i < uint(len(s)) && s[i].rtid == rtid { fn = s[i].fn } return } func (x *BasicHandle) fn(rt reflect.Type, checkFastpath, checkCodecSelfer bool) (fn *codecFn) { rtid := rt2id(rt) sp := x.rtidFns.load() if sp != nil { if _, fn = findFn(sp, rtid); fn != nil { // xdebugf("<<<< %c: found fn for %v in rtidfns of size: %v", c.n, rt, len(sp)) return } } c := x // xdebugf("#### for %c: load fn for %v in rtidfns of size: %v", c.n, rt, len(sp)) fn = new(codecFn) fi := &(fn.i) ti := c.getTypeInfo(rtid, rt) fi.ti = ti rk := reflect.Kind(ti.kind) if checkCodecSelfer && (ti.cs || ti.csp) { fn.fe = (*Encoder).selferMarshal fn.fd = (*Decoder).selferUnmarshal fi.addrF = true fi.addrD = ti.csp fi.addrE = ti.csp } else if rtid == timeTypId && !c.TimeNotBuiltin { fn.fe = (*Encoder).kTime fn.fd = (*Decoder).kTime } else if rtid == rawTypId { fn.fe = (*Encoder).raw fn.fd = (*Decoder).raw } else if rtid == rawExtTypId { fn.fe = (*Encoder).rawExt fn.fd = (*Decoder).rawExt fi.addrF = true fi.addrD = true fi.addrE = true } else if xfFn := c.getExt(rtid); xfFn != nil { fi.xfTag, fi.xfFn = xfFn.tag, xfFn.ext fn.fe = (*Encoder).ext fn.fd = (*Decoder).ext fi.addrF = true fi.addrD = true if rk == reflect.Struct || rk == reflect.Array { fi.addrE = true } } else if supportMarshalInterfaces && c.be && (ti.bm || ti.bmp) && (ti.bu || ti.bup) { fn.fe = (*Encoder).binaryMarshal fn.fd = (*Decoder).binaryUnmarshal fi.addrF = true fi.addrD = ti.bup fi.addrE = ti.bmp } else if supportMarshalInterfaces && !c.be && c.js && (ti.jm || ti.jmp) && (ti.ju || ti.jup) { //If JSON, we should check JSONMarshal before textMarshal fn.fe = (*Encoder).jsonMarshal fn.fd = (*Decoder).jsonUnmarshal fi.addrF = true fi.addrD = ti.jup fi.addrE = ti.jmp } else if supportMarshalInterfaces && !c.be && (ti.tm || ti.tmp) && (ti.tu || ti.tup) { fn.fe = (*Encoder).textMarshal fn.fd = (*Decoder).textUnmarshal fi.addrF = true fi.addrD = ti.tup fi.addrE = ti.tmp } else { if fastpathEnabled && checkFastpath && (rk == reflect.Map || rk == reflect.Slice) { if ti.pkgpath == "" { // un-named slice or map if idx := fastpathAV.index(rtid); idx != -1 { fn.fe = fastpathAV[idx].encfn fn.fd = fastpathAV[idx].decfn fi.addrD = true fi.addrF = false } } else { // use mapping for underlying type if there var rtu reflect.Type if rk == reflect.Map { rtu = reflect.MapOf(ti.key, ti.elem) } else { rtu = reflect.SliceOf(ti.elem) } rtuid := rt2id(rtu) if idx := fastpathAV.index(rtuid); idx != -1 { xfnf := fastpathAV[idx].encfn xrt := fastpathAV[idx].rt fn.fe = func(e *Encoder, xf *codecFnInfo, xrv reflect.Value) { xfnf(e, xf, xrv.Convert(xrt)) } fi.addrD = true fi.addrF = false // meaning it can be an address(ptr) or a value xfnf2 := fastpathAV[idx].decfn fn.fd = func(d *Decoder, xf *codecFnInfo, xrv reflect.Value) { if xrv.Kind() == reflect.Ptr { xfnf2(d, xf, xrv.Convert(reflect.PtrTo(xrt))) } else { xfnf2(d, xf, xrv.Convert(xrt)) } } } } } if fn.fe == nil && fn.fd == nil { switch rk { case reflect.Bool: fn.fe = (*Encoder).kBool fn.fd = (*Decoder).kBool case reflect.String: fn.fe = (*Encoder).kString fn.fd = (*Decoder).kString case reflect.Int: fn.fd = (*Decoder).kInt fn.fe = (*Encoder).kInt case reflect.Int8: fn.fe = (*Encoder).kInt8 fn.fd = (*Decoder).kInt8 case reflect.Int16: fn.fe = (*Encoder).kInt16 fn.fd = (*Decoder).kInt16 case reflect.Int32: fn.fe = (*Encoder).kInt32 fn.fd = (*Decoder).kInt32 case reflect.Int64: fn.fe = (*Encoder).kInt64 fn.fd = (*Decoder).kInt64 case reflect.Uint: fn.fd = (*Decoder).kUint fn.fe = (*Encoder).kUint case reflect.Uint8: fn.fe = (*Encoder).kUint8 fn.fd = (*Decoder).kUint8 case reflect.Uint16: fn.fe = (*Encoder).kUint16 fn.fd = (*Decoder).kUint16 case reflect.Uint32: fn.fe = (*Encoder).kUint32 fn.fd = (*Decoder).kUint32 case reflect.Uint64: fn.fe = (*Encoder).kUint64 fn.fd = (*Decoder).kUint64 case reflect.Uintptr: fn.fe = (*Encoder).kUintptr fn.fd = (*Decoder).kUintptr case reflect.Float32: fn.fe = (*Encoder).kFloat32 fn.fd = (*Decoder).kFloat32 case reflect.Float64: fn.fe = (*Encoder).kFloat64 fn.fd = (*Decoder).kFloat64 case reflect.Invalid: fn.fe = (*Encoder).kInvalid fn.fd = (*Decoder).kErr case reflect.Chan: fi.seq = seqTypeChan fn.fe = (*Encoder).kSlice fn.fd = (*Decoder).kSlice case reflect.Slice: fi.seq = seqTypeSlice fn.fe = (*Encoder).kSlice fn.fd = (*Decoder).kSlice case reflect.Array: fi.seq = seqTypeArray fn.fe = (*Encoder).kSlice fi.addrF = false fi.addrD = false rt2 := reflect.SliceOf(ti.elem) fn.fd = func(d *Decoder, xf *codecFnInfo, xrv reflect.Value) { d.h.fn(rt2, true, false).fd(d, xf, xrv.Slice(0, xrv.Len())) } // fn.fd = (*Decoder).kArray case reflect.Struct: if ti.anyOmitEmpty || ti.mf || ti.mfp { fn.fe = (*Encoder).kStruct } else { fn.fe = (*Encoder).kStructNoOmitempty } fn.fd = (*Decoder).kStruct case reflect.Map: fn.fe = (*Encoder).kMap fn.fd = (*Decoder).kMap case reflect.Interface: // encode: reflect.Interface are handled already by preEncodeValue fn.fd = (*Decoder).kInterface fn.fe = (*Encoder).kErr default: // reflect.Ptr and reflect.Interface are handled already by preEncodeValue fn.fe = (*Encoder).kErr fn.fd = (*Decoder).kErr } } } c.mu.Lock() var sp2 []codecRtidFn sp = c.rtidFns.load() if sp == nil { sp2 = []codecRtidFn{{rtid, fn}} c.rtidFns.store(sp2) // xdebugf(">>>> adding rt: %v to rtidfns of size: %v", rt, len(sp2)) // xdebugf(">>>> loading stored rtidfns of size: %v", len(c.rtidFns.load())) } else { idx, fn2 := findFn(sp, rtid) if fn2 == nil { sp2 = make([]codecRtidFn, len(sp)+1) copy(sp2, sp[:idx]) copy(sp2[idx+1:], sp[idx:]) sp2[idx] = codecRtidFn{rtid, fn} c.rtidFns.store(sp2) // xdebugf(">>>> adding rt: %v to rtidfns of size: %v", rt, len(sp2)) } } c.mu.Unlock() return } // Handle defines a specific encoding format. It also stores any runtime state // used during an Encoding or Decoding session e.g. stored state about Types, etc. // // Once a handle is configured, it can be shared across multiple Encoders and Decoders. // // Note that a Handle is NOT safe for concurrent modification. // Consequently, do not modify it after it is configured if shared among // multiple Encoders and Decoders in different goroutines. // // Consequently, the typical usage model is that a Handle is pre-configured // before first time use, and not modified while in use. // Such a pre-configured Handle is safe for concurrent access. type Handle interface { Name() string // return the basic handle. It may not have been inited. // Prefer to use basicHandle() helper function that ensures it has been inited. getBasicHandle() *BasicHandle recreateEncDriver(encDriver) bool newEncDriver(w *Encoder) encDriver newDecDriver(r *Decoder) decDriver isBinary() bool hasElemSeparators() bool // IsBuiltinType(rtid uintptr) bool } // Raw represents raw formatted bytes. // We "blindly" store it during encode and retrieve the raw bytes during decode. // Note: it is dangerous during encode, so we may gate the behaviour // behind an Encode flag which must be explicitly set. type Raw []byte // RawExt represents raw unprocessed extension data. // Some codecs will decode extension data as a *RawExt // if there is no registered extension for the tag. // // Only one of Data or Value is nil. // If Data is nil, then the content of the RawExt is in the Value. type RawExt struct { Tag uint64 // Data is the []byte which represents the raw ext. If nil, ext is exposed in Value. // Data is used by codecs (e.g. binc, msgpack, simple) which do custom serialization of types Data []byte // Value represents the extension, if Data is nil. // Value is used by codecs (e.g. cbor, json) which leverage the format to do // custom serialization of the types. Value interface{} } // BytesExt handles custom (de)serialization of types to/from []byte. // It is used by codecs (e.g. binc, msgpack, simple) which do custom serialization of the types. type BytesExt interface { // WriteExt converts a value to a []byte. // // Note: v is a pointer iff the registered extension type is a struct or array kind. WriteExt(v interface{}) []byte // ReadExt updates a value from a []byte. // // Note: dst is always a pointer kind to the registered extension type. ReadExt(dst interface{}, src []byte) } // InterfaceExt handles custom (de)serialization of types to/from another interface{} value. // The Encoder or Decoder will then handle the further (de)serialization of that known type. // // It is used by codecs (e.g. cbor, json) which use the format to do custom serialization of types. type InterfaceExt interface { // ConvertExt converts a value into a simpler interface for easy encoding // e.g. convert time.Time to int64. // // Note: v is a pointer iff the registered extension type is a struct or array kind. ConvertExt(v interface{}) interface{} // UpdateExt updates a value from a simpler interface for easy decoding // e.g. convert int64 to time.Time. // // Note: dst is always a pointer kind to the registered extension type. UpdateExt(dst interface{}, src interface{}) } // Ext handles custom (de)serialization of custom types / extensions. type Ext interface { BytesExt InterfaceExt } // addExtWrapper is a wrapper implementation to support former AddExt exported method. type addExtWrapper struct { encFn func(reflect.Value) ([]byte, error) decFn func(reflect.Value, []byte) error } func (x addExtWrapper) WriteExt(v interface{}) []byte { bs, err := x.encFn(reflect.ValueOf(v)) if err != nil { panic(err) } return bs } func (x addExtWrapper) ReadExt(v interface{}, bs []byte) { if err := x.decFn(reflect.ValueOf(v), bs); err != nil { panic(err) } } func (x addExtWrapper) ConvertExt(v interface{}) interface{} { return x.WriteExt(v) } func (x addExtWrapper) UpdateExt(dest interface{}, v interface{}) { x.ReadExt(dest, v.([]byte)) } type extWrapper struct { BytesExt InterfaceExt } type bytesExtFailer struct{} func (bytesExtFailer) WriteExt(v interface{}) []byte { panicv.errorstr("BytesExt.WriteExt is not supported") return nil } func (bytesExtFailer) ReadExt(v interface{}, bs []byte) { panicv.errorstr("BytesExt.ReadExt is not supported") } type interfaceExtFailer struct{} func (interfaceExtFailer) ConvertExt(v interface{}) interface{} { panicv.errorstr("InterfaceExt.ConvertExt is not supported") return nil } func (interfaceExtFailer) UpdateExt(dest interface{}, v interface{}) { panicv.errorstr("InterfaceExt.UpdateExt is not supported") } type binaryEncodingType struct{} func (binaryEncodingType) isBinary() bool { return true } type textEncodingType struct{} func (textEncodingType) isBinary() bool { return false } // noBuiltInTypes is embedded into many types which do not support builtins // e.g. msgpack, simple, cbor. // type noBuiltInTypeChecker struct{} // func (noBuiltInTypeChecker) IsBuiltinType(rt uintptr) bool { return false } // type noBuiltInTypes struct{ noBuiltInTypeChecker } type noBuiltInTypes struct{} func (noBuiltInTypes) EncodeBuiltin(rt uintptr, v interface{}) {} func (noBuiltInTypes) DecodeBuiltin(rt uintptr, v interface{}) {} // type noStreamingCodec struct{} // func (noStreamingCodec) CheckBreak() bool { return false } // func (noStreamingCodec) hasElemSeparators() bool { return false } type noElemSeparators struct{} func (noElemSeparators) hasElemSeparators() (v bool) { return } func (noElemSeparators) recreateEncDriver(e encDriver) (v bool) { return } // bigenHelper. // Users must already slice the x completely, because we will not reslice. type bigenHelper struct { x []byte // must be correctly sliced to appropriate len. slicing is a cost. w *encWriterSwitch } func (z bigenHelper) writeUint16(v uint16) { bigen.PutUint16(z.x, v) z.w.writeb(z.x) } func (z bigenHelper) writeUint32(v uint32) { bigen.PutUint32(z.x, v) z.w.writeb(z.x) } func (z bigenHelper) writeUint64(v uint64) { bigen.PutUint64(z.x, v) z.w.writeb(z.x) } type extTypeTagFn struct { rtid uintptr rtidptr uintptr rt reflect.Type tag uint64 ext Ext _ [1]uint64 // padding } type extHandle []extTypeTagFn // AddExt registes an encode and decode function for a reflect.Type. // To deregister an Ext, call AddExt with nil encfn and/or nil decfn. // // Deprecated: Use SetBytesExt or SetInterfaceExt on the Handle instead. func (o *extHandle) AddExt(rt reflect.Type, tag byte, encfn func(reflect.Value) ([]byte, error), decfn func(reflect.Value, []byte) error) (err error) { if encfn == nil || decfn == nil { return o.SetExt(rt, uint64(tag), nil) } return o.SetExt(rt, uint64(tag), addExtWrapper{encfn, decfn}) } // SetExt will set the extension for a tag and reflect.Type. // Note that the type must be a named type, and specifically not a pointer or Interface. // An error is returned if that is not honored. // To Deregister an ext, call SetExt with nil Ext. // // Deprecated: Use SetBytesExt or SetInterfaceExt on the Handle instead. func (o *extHandle) SetExt(rt reflect.Type, tag uint64, ext Ext) (err error) { // o is a pointer, because we may need to initialize it rk := rt.Kind() for rk == reflect.Ptr { rt = rt.Elem() rk = rt.Kind() } if rt.PkgPath() == "" || rk == reflect.Interface { // || rk == reflect.Ptr { return fmt.Errorf("codec.Handle.SetExt: Takes named type, not a pointer or interface: %v", rt) } rtid := rt2id(rt) switch rtid { case timeTypId, rawTypId, rawExtTypId: // all natively supported type, so cannot have an extension return // TODO: should we silently ignore, or return an error??? } // if o == nil { // return errors.New("codec.Handle.SetExt: extHandle not initialized") // } o2 := *o // if o2 == nil { // return errors.New("codec.Handle.SetExt: extHandle not initialized") // } for i := range o2 { v := &o2[i] if v.rtid == rtid { v.tag, v.ext = tag, ext return } } rtidptr := rt2id(reflect.PtrTo(rt)) *o = append(o2, extTypeTagFn{rtid, rtidptr, rt, tag, ext, [1]uint64{}}) return } func (o extHandle) getExt(rtid uintptr) (v *extTypeTagFn) { for i := range o { v = &o[i] if v.rtid == rtid || v.rtidptr == rtid { return } } return nil } func (o extHandle) getExtForTag(tag uint64) (v *extTypeTagFn) { for i := range o { v = &o[i] if v.tag == tag { return } } return nil } type intf2impl struct { rtid uintptr // for intf impl reflect.Type // _ [1]uint64 // padding // not-needed, as *intf2impl is never returned. } type intf2impls []intf2impl // Intf2Impl maps an interface to an implementing type. // This allows us support infering the concrete type // and populating it when passed an interface. // e.g. var v io.Reader can be decoded as a bytes.Buffer, etc. // // Passing a nil impl will clear the mapping. func (o *intf2impls) Intf2Impl(intf, impl reflect.Type) (err error) { if impl != nil && !impl.Implements(intf) { return fmt.Errorf("Intf2Impl: %v does not implement %v", impl, intf) } rtid := rt2id(intf) o2 := *o for i := range o2 { v := &o2[i] if v.rtid == rtid { v.impl = impl return } } *o = append(o2, intf2impl{rtid, impl}) return } func (o intf2impls) intf2impl(rtid uintptr) (rv reflect.Value) { for i := range o { v := &o[i] if v.rtid == rtid { if v.impl == nil { return } if v.impl.Kind() == reflect.Ptr { return reflect.New(v.impl.Elem()) } return reflect.New(v.impl).Elem() } } return } type structFieldInfoFlag uint8 const ( _ structFieldInfoFlag = 1 << iota structFieldInfoFlagReady structFieldInfoFlagOmitEmpty ) func (x *structFieldInfoFlag) flagSet(f structFieldInfoFlag) { *x = *x | f } func (x *structFieldInfoFlag) flagClr(f structFieldInfoFlag) { *x = *x &^ f } func (x structFieldInfoFlag) flagGet(f structFieldInfoFlag) bool { return x&f != 0 } func (x structFieldInfoFlag) omitEmpty() bool { return x.flagGet(structFieldInfoFlagOmitEmpty) } func (x structFieldInfoFlag) ready() bool { return x.flagGet(structFieldInfoFlagReady) } type structFieldInfo struct { encName string // encode name fieldName string // field name is [maxLevelsEmbedding]uint16 // (recursive/embedded) field index in struct nis uint8 // num levels of embedding. if 1, then it's not embedded. encNameAsciiAlphaNum bool // the encName only contains ascii alphabet and numbers structFieldInfoFlag _ [1]byte // padding } func (si *structFieldInfo) setToZeroValue(v reflect.Value) { if v, valid := si.field(v, false); valid { v.Set(reflect.Zero(v.Type())) } } // rv returns the field of the struct. // If anonymous, it returns an Invalid func (si *structFieldInfo) field(v reflect.Value, update bool) (rv2 reflect.Value, valid bool) { // replicate FieldByIndex for i, x := range si.is { if uint8(i) == si.nis { break } if v, valid = baseStructRv(v, update); !valid { return } v = v.Field(int(x)) } return v, true } // func (si *structFieldInfo) fieldval(v reflect.Value, update bool) reflect.Value { // v, _ = si.field(v, update) // return v // } func parseStructInfo(stag string) (toArray, omitEmpty bool, keytype valueType) { keytype = valueTypeString // default if stag == "" { return } for i, s := range strings.Split(stag, ",") { if i == 0 { } else { switch s { case "omitempty": omitEmpty = true case "toarray": toArray = true case "int": keytype = valueTypeInt case "uint": keytype = valueTypeUint case "float": keytype = valueTypeFloat // case "bool": // keytype = valueTypeBool case "string": keytype = valueTypeString } } } return } func (si *structFieldInfo) parseTag(stag string) { // if fname == "" { // panic(errNoFieldNameToStructFieldInfo) // } if stag == "" { return } for i, s := range strings.Split(stag, ",") { if i == 0 { if s != "" { si.encName = s } } else { switch s { case "omitempty": si.flagSet(structFieldInfoFlagOmitEmpty) // si.omitEmpty = true // case "toarray": // si.toArray = true } } } } type sfiSortedByEncName []*structFieldInfo func (p sfiSortedByEncName) Len() int { return len(p) } func (p sfiSortedByEncName) Less(i, j int) bool { return p[uint(i)].encName < p[uint(j)].encName } func (p sfiSortedByEncName) Swap(i, j int) { p[uint(i)], p[uint(j)] = p[uint(j)], p[uint(i)] } const structFieldNodeNumToCache = 4 type structFieldNodeCache struct { rv [structFieldNodeNumToCache]reflect.Value idx [structFieldNodeNumToCache]uint32 num uint8 } func (x *structFieldNodeCache) get(key uint32) (fv reflect.Value, valid bool) { for i, k := range &x.idx { if uint8(i) == x.num { return // break } if key == k { return x.rv[i], true } } return } func (x *structFieldNodeCache) tryAdd(fv reflect.Value, key uint32) { if x.num < structFieldNodeNumToCache { x.rv[x.num] = fv x.idx[x.num] = key x.num++ return } } type structFieldNode struct { v reflect.Value cache2 structFieldNodeCache cache3 structFieldNodeCache update bool } func (x *structFieldNode) field(si *structFieldInfo) (fv reflect.Value) { // return si.fieldval(x.v, x.update) // Note: we only cache if nis=2 or nis=3 i.e. up to 2 levels of embedding // This mostly saves us time on the repeated calls to v.Elem, v.Field, etc. var valid bool switch si.nis { case 1: fv = x.v.Field(int(si.is[0])) case 2: if fv, valid = x.cache2.get(uint32(si.is[0])); valid { fv = fv.Field(int(si.is[1])) return } fv = x.v.Field(int(si.is[0])) if fv, valid = baseStructRv(fv, x.update); !valid { return } x.cache2.tryAdd(fv, uint32(si.is[0])) fv = fv.Field(int(si.is[1])) case 3: var key uint32 = uint32(si.is[0])<<16 | uint32(si.is[1]) if fv, valid = x.cache3.get(key); valid { fv = fv.Field(int(si.is[2])) return } fv = x.v.Field(int(si.is[0])) if fv, valid = baseStructRv(fv, x.update); !valid { return } fv = fv.Field(int(si.is[1])) if fv, valid = baseStructRv(fv, x.update); !valid { return } x.cache3.tryAdd(fv, key) fv = fv.Field(int(si.is[2])) default: fv, _ = si.field(x.v, x.update) } return } func baseStructRv(v reflect.Value, update bool) (v2 reflect.Value, valid bool) { for v.Kind() == reflect.Ptr { if v.IsNil() { if !update { return } v.Set(reflect.New(v.Type().Elem())) } v = v.Elem() } return v, true } type typeInfoFlag uint8 const ( typeInfoFlagComparable = 1 << iota typeInfoFlagIsZeroer typeInfoFlagIsZeroerPtr ) // typeInfo keeps information about each (non-ptr) type referenced in the encode/decode sequence. // // During an encode/decode sequence, we work as below: // - If base is a built in type, en/decode base value // - If base is registered as an extension, en/decode base value // - If type is binary(M/Unm)arshaler, call Binary(M/Unm)arshal method // - If type is text(M/Unm)arshaler, call Text(M/Unm)arshal method // - Else decode appropriately based on the reflect.Kind type typeInfo struct { rt reflect.Type elem reflect.Type pkgpath string rtid uintptr // rv0 reflect.Value // saved zero value, used if immutableKind numMeth uint16 // number of methods kind uint8 chandir uint8 anyOmitEmpty bool // true if a struct, and any of the fields are tagged "omitempty" toArray bool // whether this (struct) type should be encoded as an array keyType valueType // if struct, how is the field name stored in a stream? default is string mbs bool // base type (T or *T) is a MapBySlice // ---- cpu cache line boundary? sfiSort []*structFieldInfo // sorted. Used when enc/dec struct to map. sfiSrc []*structFieldInfo // unsorted. Used when enc/dec struct to array. key reflect.Type // ---- cpu cache line boundary? // sfis []structFieldInfo // all sfi, in src order, as created. sfiNamesSort []byte // all names, with indexes into the sfiSort // format of marshal type fields below: [btj][mu]p? OR csp? bm bool // T is a binaryMarshaler bmp bool // *T is a binaryMarshaler bu bool // T is a binaryUnmarshaler bup bool // *T is a binaryUnmarshaler tm bool // T is a textMarshaler tmp bool // *T is a textMarshaler tu bool // T is a textUnmarshaler tup bool // *T is a textUnmarshaler jm bool // T is a jsonMarshaler jmp bool // *T is a jsonMarshaler ju bool // T is a jsonUnmarshaler jup bool // *T is a jsonUnmarshaler cs bool // T is a Selfer csp bool // *T is a Selfer mf bool // T is a MissingFielder mfp bool // *T is a MissingFielder // other flags, with individual bits representing if set. flags typeInfoFlag infoFieldOmitempty bool _ [6]byte // padding _ [2]uint64 // padding } func (ti *typeInfo) isFlag(f typeInfoFlag) bool { return ti.flags&f != 0 } func (ti *typeInfo) indexForEncName(name []byte) (index int16) { var sn []byte if len(name)+2 <= 32 { var buf [32]byte // should not escape to heap sn = buf[:len(name)+2] } else { sn = make([]byte, len(name)+2) } copy(sn[1:], name) sn[0], sn[len(sn)-1] = tiSep2(name), 0xff j := bytes.Index(ti.sfiNamesSort, sn) if j < 0 { return -1 } index = int16(uint16(ti.sfiNamesSort[j+len(sn)+1]) | uint16(ti.sfiNamesSort[j+len(sn)])<<8) return } type rtid2ti struct { rtid uintptr ti *typeInfo } // TypeInfos caches typeInfo for each type on first inspection. // // It is configured with a set of tag keys, which are used to get // configuration for the type. type TypeInfos struct { // infos: formerly map[uintptr]*typeInfo, now *[]rtid2ti, 2 words expected infos atomicTypeInfoSlice mu sync.Mutex tags []string _ [2]uint64 // padding } // NewTypeInfos creates a TypeInfos given a set of struct tags keys. // // This allows users customize the struct tag keys which contain configuration // of their types. func NewTypeInfos(tags []string) *TypeInfos { return &TypeInfos{tags: tags} } func (x *TypeInfos) structTag(t reflect.StructTag) (s string) { // check for tags: codec, json, in that order. // this allows seamless support for many configured structs. for _, x := range x.tags { s = t.Get(x) if s != "" { return s } } return } func findTypeInfo(s []rtid2ti, rtid uintptr) (i uint, ti *typeInfo) { // binary search. adapted from sort/search.go. // Note: we use goto (instead of for loop) so this can be inlined. // if sp == nil { // return -1, nil // } // s := *sp // h, i, j := 0, 0, len(s) var h uint // var h, i uint var j = uint(len(s)) LOOP: if i < j { h = i + (j-i)/2 if s[h].rtid < rtid { i = h + 1 } else { j = h } goto LOOP } if i < uint(len(s)) && s[i].rtid == rtid { ti = s[i].ti } return } func (x *TypeInfos) get(rtid uintptr, rt reflect.Type) (pti *typeInfo) { sp := x.infos.load() if sp != nil { _, pti = findTypeInfo(sp, rtid) if pti != nil { return } } rk := rt.Kind() if rk == reflect.Ptr { // || (rk == reflect.Interface && rtid != intfTypId) { panicv.errorf("invalid kind passed to TypeInfos.get: %v - %v", rk, rt) } // do not hold lock while computing this. // it may lead to duplication, but that's ok. ti := typeInfo{ rt: rt, rtid: rtid, kind: uint8(rk), pkgpath: rt.PkgPath(), keyType: valueTypeString, // default it - so it's never 0 } // ti.rv0 = reflect.Zero(rt) // ti.comparable = rt.Comparable() ti.numMeth = uint16(rt.NumMethod()) ti.bm, ti.bmp = implIntf(rt, binaryMarshalerTyp) ti.bu, ti.bup = implIntf(rt, binaryUnmarshalerTyp) ti.tm, ti.tmp = implIntf(rt, textMarshalerTyp) ti.tu, ti.tup = implIntf(rt, textUnmarshalerTyp) ti.jm, ti.jmp = implIntf(rt, jsonMarshalerTyp) ti.ju, ti.jup = implIntf(rt, jsonUnmarshalerTyp) ti.cs, ti.csp = implIntf(rt, selferTyp) ti.mf, ti.mfp = implIntf(rt, missingFielderTyp) b1, b2 := implIntf(rt, iszeroTyp) if b1 { ti.flags |= typeInfoFlagIsZeroer } if b2 { ti.flags |= typeInfoFlagIsZeroerPtr } if rt.Comparable() { ti.flags |= typeInfoFlagComparable } switch rk { case reflect.Struct: var omitEmpty bool if f, ok := rt.FieldByName(structInfoFieldName); ok { ti.toArray, omitEmpty, ti.keyType = parseStructInfo(x.structTag(f.Tag)) ti.infoFieldOmitempty = omitEmpty } else { ti.keyType = valueTypeString } pp, pi := pool.tiLoad() pv := pi.(*typeInfoLoadArray) pv.etypes[0] = ti.rtid // vv := typeInfoLoad{pv.fNames[:0], pv.encNames[:0], pv.etypes[:1], pv.sfis[:0]} vv := typeInfoLoad{pv.etypes[:1], pv.sfis[:0]} x.rget(rt, rtid, omitEmpty, nil, &vv) // ti.sfis = vv.sfis ti.sfiSrc, ti.sfiSort, ti.sfiNamesSort, ti.anyOmitEmpty = rgetResolveSFI(rt, vv.sfis, pv) pp.Put(pi) case reflect.Map: ti.elem = rt.Elem() ti.key = rt.Key() case reflect.Slice: ti.mbs, _ = implIntf(rt, mapBySliceTyp) ti.elem = rt.Elem() case reflect.Chan: ti.elem = rt.Elem() ti.chandir = uint8(rt.ChanDir()) case reflect.Array, reflect.Ptr: ti.elem = rt.Elem() } // sfi = sfiSrc x.mu.Lock() sp = x.infos.load() var sp2 []rtid2ti if sp == nil { pti = &ti sp2 = []rtid2ti{{rtid, pti}} x.infos.store(sp2) } else { var idx uint idx, pti = findTypeInfo(sp, rtid) if pti == nil { pti = &ti sp2 = make([]rtid2ti, len(sp)+1) copy(sp2, sp[:idx]) copy(sp2[idx+1:], sp[idx:]) sp2[idx] = rtid2ti{rtid, pti} x.infos.store(sp2) } } x.mu.Unlock() return } func (x *TypeInfos) rget(rt reflect.Type, rtid uintptr, omitEmpty bool, indexstack []uint16, pv *typeInfoLoad) { // Read up fields and store how to access the value. // // It uses go's rules for message selectors, // which say that the field with the shallowest depth is selected. // // Note: we consciously use slices, not a map, to simulate a set. // Typically, types have < 16 fields, // and iteration using equals is faster than maps there flen := rt.NumField() if flen > (1< %v fields are not supported - has %v fields", (1<= 0; i-- { // bounds-check elimination b := si.encName[i] if (b >= '0' && b <= '9') || (b >= 'a' && b <= 'z') || (b >= 'A' && b <= 'Z') { continue } si.encNameAsciiAlphaNum = false break } si.fieldName = f.Name si.flagSet(structFieldInfoFlagReady) // pv.encNames = append(pv.encNames, si.encName) // si.ikind = int(f.Type.Kind()) if len(indexstack) > maxLevelsEmbedding-1 { panicv.errorf("codec: only supports up to %v depth of embedding - type has %v depth", maxLevelsEmbedding-1, len(indexstack)) } si.nis = uint8(len(indexstack)) + 1 copy(si.is[:], indexstack) si.is[len(indexstack)] = j if omitEmpty { si.flagSet(structFieldInfoFlagOmitEmpty) } pv.sfis = append(pv.sfis, si) } } func tiSep(name string) uint8 { // (xn[0]%64) // (between 192-255 - outside ascii BMP) // return 0xfe - (name[0] & 63) // return 0xfe - (name[0] & 63) - uint8(len(name)) // return 0xfe - (name[0] & 63) - uint8(len(name)&63) // return ((0xfe - (name[0] & 63)) & 0xf8) | (uint8(len(name) & 0x07)) return 0xfe - (name[0] & 63) - uint8(len(name)&63) } func tiSep2(name []byte) uint8 { return 0xfe - (name[0] & 63) - uint8(len(name)&63) } // resolves the struct field info got from a call to rget. // Returns a trimmed, unsorted and sorted []*structFieldInfo. func rgetResolveSFI(rt reflect.Type, x []structFieldInfo, pv *typeInfoLoadArray) ( y, z []*structFieldInfo, ss []byte, anyOmitEmpty bool) { sa := pv.sfiidx[:0] sn := pv.b[:] n := len(x) var xn string var ui uint16 var sep byte for i := range x { ui = uint16(i) xn = x[i].encName // fieldName or encName? use encName for now. if len(xn)+2 > cap(pv.b) { sn = make([]byte, len(xn)+2) } else { sn = sn[:len(xn)+2] } // use a custom sep, so that misses are less frequent, // since the sep (first char in search) is as unique as first char in field name. sep = tiSep(xn) sn[0], sn[len(sn)-1] = sep, 0xff copy(sn[1:], xn) j := bytes.Index(sa, sn) if j == -1 { sa = append(sa, sep) sa = append(sa, xn...) sa = append(sa, 0xff, byte(ui>>8), byte(ui)) } else { index := uint16(sa[j+len(sn)+1]) | uint16(sa[j+len(sn)])<<8 // one of them must be reset to nil, // and the index updated appropriately to the other one if x[i].nis == x[index].nis { } else if x[i].nis < x[index].nis { sa[j+len(sn)], sa[j+len(sn)+1] = byte(ui>>8), byte(ui) if x[index].ready() { x[index].flagClr(structFieldInfoFlagReady) n-- } } else { if x[i].ready() { x[i].flagClr(structFieldInfoFlagReady) n-- } } } } var w []structFieldInfo sharingArray := len(x) <= typeInfoLoadArraySfisLen // sharing array with typeInfoLoadArray if sharingArray { w = make([]structFieldInfo, n) } // remove all the nils (non-ready) y = make([]*structFieldInfo, n) n = 0 var sslen int for i := range x { if !x[i].ready() { continue } if !anyOmitEmpty && x[i].omitEmpty() { anyOmitEmpty = true } if sharingArray { w[n] = x[i] y[n] = &w[n] } else { y[n] = &x[i] } sslen = sslen + len(x[i].encName) + 4 n++ } if n != len(y) { panicv.errorf("failure reading struct %v - expecting %d of %d valid fields, got %d", rt, len(y), len(x), n) } z = make([]*structFieldInfo, len(y)) copy(z, y) sort.Sort(sfiSortedByEncName(z)) sharingArray = len(sa) <= typeInfoLoadArraySfiidxLen if sharingArray { ss = make([]byte, 0, sslen) } else { ss = sa[:0] // reuse the newly made sa array if necessary } for i := range z { xn = z[i].encName sep = tiSep(xn) ui = uint16(i) ss = append(ss, sep) ss = append(ss, xn...) ss = append(ss, 0xff, byte(ui>>8), byte(ui)) } return } func implIntf(rt, iTyp reflect.Type) (base bool, indir bool) { return rt.Implements(iTyp), reflect.PtrTo(rt).Implements(iTyp) } // isEmptyStruct is only called from isEmptyValue, and checks if a struct is empty: // - does it implement IsZero() bool // - is it comparable, and can i compare directly using == // - if checkStruct, then walk through the encodable fields // and check if they are empty or not. func isEmptyStruct(v reflect.Value, tinfos *TypeInfos, deref, checkStruct bool) bool { // v is a struct kind - no need to check again. // We only check isZero on a struct kind, to reduce the amount of times // that we lookup the rtid and typeInfo for each type as we walk the tree. vt := v.Type() rtid := rt2id(vt) if tinfos == nil { tinfos = defTypeInfos } ti := tinfos.get(rtid, vt) if ti.rtid == timeTypId { return rv2i(v).(time.Time).IsZero() } if ti.isFlag(typeInfoFlagIsZeroerPtr) && v.CanAddr() { return rv2i(v.Addr()).(isZeroer).IsZero() } if ti.isFlag(typeInfoFlagIsZeroer) { return rv2i(v).(isZeroer).IsZero() } if ti.isFlag(typeInfoFlagComparable) { return rv2i(v) == rv2i(reflect.Zero(vt)) } if !checkStruct { return false } // We only care about what we can encode/decode, // so that is what we use to check omitEmpty. for _, si := range ti.sfiSrc { sfv, valid := si.field(v, false) if valid && !isEmptyValue(sfv, tinfos, deref, checkStruct) { return false } } return true } // func roundFloat(x float64) float64 { // t := math.Trunc(x) // if math.Abs(x-t) >= 0.5 { // return t + math.Copysign(1, x) // } // return t // } func panicToErr(h errDecorator, err *error) { // Note: This method MUST be called directly from defer i.e. defer panicToErr ... // else it seems the recover is not fully handled if recoverPanicToErr { if x := recover(); x != nil { // fmt.Printf("panic'ing with: %v\n", x) // debug.PrintStack() panicValToErr(h, x, err) } } } func panicValToErr(h errDecorator, v interface{}, err *error) { switch xerr := v.(type) { case nil: case error: switch xerr { case nil: case io.EOF, io.ErrUnexpectedEOF, errEncoderNotInitialized, errDecoderNotInitialized: // treat as special (bubble up) *err = xerr default: h.wrapErr(xerr, err) } case string: if xerr != "" { h.wrapErr(xerr, err) } case fmt.Stringer: if xerr != nil { h.wrapErr(xerr, err) } default: h.wrapErr(v, err) } } func isImmutableKind(k reflect.Kind) (v bool) { // return immutableKindsSet[k] // since we know reflect.Kind is in range 0..31, then use the k%32 == k constraint return immutableKindsSet[k%reflect.Kind(len(immutableKindsSet))] // bounds-check-elimination } // ---- type codecFnInfo struct { ti *typeInfo xfFn Ext xfTag uint64 seq seqType addrD bool addrF bool // if addrD, this says whether decode function can take a value or a ptr addrE bool } // codecFn encapsulates the captured variables and the encode function. // This way, we only do some calculations one times, and pass to the // code block that should be called (encapsulated in a function) // instead of executing the checks every time. type codecFn struct { i codecFnInfo fe func(*Encoder, *codecFnInfo, reflect.Value) fd func(*Decoder, *codecFnInfo, reflect.Value) _ [1]uint64 // padding } type codecRtidFn struct { rtid uintptr fn *codecFn } // ---- // these "checkOverflow" functions must be inlinable, and not call anybody. // Overflow means that the value cannot be represented without wrapping/overflow. // Overflow=false does not mean that the value can be represented without losing precision // (especially for floating point). type checkOverflow struct{} // func (checkOverflow) Float16(f float64) (overflow bool) { // panicv.errorf("unimplemented") // if f < 0 { // f = -f // } // return math.MaxFloat32 < f && f <= math.MaxFloat64 // } func (checkOverflow) Float32(v float64) (overflow bool) { if v < 0 { v = -v } return math.MaxFloat32 < v && v <= math.MaxFloat64 } func (checkOverflow) Uint(v uint64, bitsize uint8) (overflow bool) { if bitsize == 0 || bitsize >= 64 || v == 0 { return } if trunc := (v << (64 - bitsize)) >> (64 - bitsize); v != trunc { overflow = true } return } func (checkOverflow) Int(v int64, bitsize uint8) (overflow bool) { if bitsize == 0 || bitsize >= 64 || v == 0 { return } if trunc := (v << (64 - bitsize)) >> (64 - bitsize); v != trunc { overflow = true } return } func (checkOverflow) SignedInt(v uint64) (overflow bool) { //e.g. -127 to 128 for int8 pos := (v >> 63) == 0 ui2 := v & 0x7fffffffffffffff if pos { if ui2 > math.MaxInt64 { overflow = true } } else { if ui2 > math.MaxInt64-1 { overflow = true } } return } func (x checkOverflow) Float32V(v float64) float64 { if x.Float32(v) { panicv.errorf("float32 overflow: %v", v) } return v } func (x checkOverflow) UintV(v uint64, bitsize uint8) uint64 { if x.Uint(v, bitsize) { panicv.errorf("uint64 overflow: %v", v) } return v } func (x checkOverflow) IntV(v int64, bitsize uint8) int64 { if x.Int(v, bitsize) { panicv.errorf("int64 overflow: %v", v) } return v } func (x checkOverflow) SignedIntV(v uint64) int64 { if x.SignedInt(v) { panicv.errorf("uint64 to int64 overflow: %v", v) } return int64(v) } // ------------------ SORT ----------------- func isNaN(f float64) bool { return f != f } // ----------------------- type ioFlusher interface { Flush() error } type ioPeeker interface { Peek(int) ([]byte, error) } type ioBuffered interface { Buffered() int } // ----------------------- type intSlice []int64 type uintSlice []uint64 // type uintptrSlice []uintptr type floatSlice []float64 type boolSlice []bool type stringSlice []string // type bytesSlice [][]byte func (p intSlice) Len() int { return len(p) } func (p intSlice) Less(i, j int) bool { return p[uint(i)] < p[uint(j)] } func (p intSlice) Swap(i, j int) { p[uint(i)], p[uint(j)] = p[uint(j)], p[uint(i)] } func (p uintSlice) Len() int { return len(p) } func (p uintSlice) Less(i, j int) bool { return p[uint(i)] < p[uint(j)] } func (p uintSlice) Swap(i, j int) { p[uint(i)], p[uint(j)] = p[uint(j)], p[uint(i)] } // func (p uintptrSlice) Len() int { return len(p) } // func (p uintptrSlice) Less(i, j int) bool { return p[uint(i)] < p[uint(j)] } // func (p uintptrSlice) Swap(i, j int) { p[uint(i)], p[uint(j)] = p[uint(j)], p[uint(i)] } func (p floatSlice) Len() int { return len(p) } func (p floatSlice) Less(i, j int) bool { return p[uint(i)] < p[uint(j)] || isNaN(p[uint(i)]) && !isNaN(p[uint(j)]) } func (p floatSlice) Swap(i, j int) { p[uint(i)], p[uint(j)] = p[uint(j)], p[uint(i)] } func (p stringSlice) Len() int { return len(p) } func (p stringSlice) Less(i, j int) bool { return p[uint(i)] < p[uint(j)] } func (p stringSlice) Swap(i, j int) { p[uint(i)], p[uint(j)] = p[uint(j)], p[uint(i)] } // func (p bytesSlice) Len() int { return len(p) } // func (p bytesSlice) Less(i, j int) bool { return bytes.Compare(p[uint(i)], p[uint(j)]) == -1 } // func (p bytesSlice) Swap(i, j int) { p[uint(i)], p[uint(j)] = p[uint(j)], p[uint(i)] } func (p boolSlice) Len() int { return len(p) } func (p boolSlice) Less(i, j int) bool { return !p[uint(i)] && p[uint(j)] } func (p boolSlice) Swap(i, j int) { p[uint(i)], p[uint(j)] = p[uint(j)], p[uint(i)] } // --------------------- type sfiRv struct { v *structFieldInfo r reflect.Value } type intRv struct { v int64 r reflect.Value } type intRvSlice []intRv type uintRv struct { v uint64 r reflect.Value } type uintRvSlice []uintRv type floatRv struct { v float64 r reflect.Value } type floatRvSlice []floatRv type boolRv struct { v bool r reflect.Value } type boolRvSlice []boolRv type stringRv struct { v string r reflect.Value } type stringRvSlice []stringRv type bytesRv struct { v []byte r reflect.Value } type bytesRvSlice []bytesRv type timeRv struct { v time.Time r reflect.Value } type timeRvSlice []timeRv func (p intRvSlice) Len() int { return len(p) } func (p intRvSlice) Less(i, j int) bool { return p[uint(i)].v < p[uint(j)].v } func (p intRvSlice) Swap(i, j int) { p[uint(i)], p[uint(j)] = p[uint(j)], p[uint(i)] } func (p uintRvSlice) Len() int { return len(p) } func (p uintRvSlice) Less(i, j int) bool { return p[uint(i)].v < p[uint(j)].v } func (p uintRvSlice) Swap(i, j int) { p[uint(i)], p[uint(j)] = p[uint(j)], p[uint(i)] } func (p floatRvSlice) Len() int { return len(p) } func (p floatRvSlice) Less(i, j int) bool { return p[uint(i)].v < p[uint(j)].v || isNaN(p[uint(i)].v) && !isNaN(p[uint(j)].v) } func (p floatRvSlice) Swap(i, j int) { p[uint(i)], p[uint(j)] = p[uint(j)], p[uint(i)] } func (p stringRvSlice) Len() int { return len(p) } func (p stringRvSlice) Less(i, j int) bool { return p[uint(i)].v < p[uint(j)].v } func (p stringRvSlice) Swap(i, j int) { p[uint(i)], p[uint(j)] = p[uint(j)], p[uint(i)] } func (p bytesRvSlice) Len() int { return len(p) } func (p bytesRvSlice) Less(i, j int) bool { return bytes.Compare(p[uint(i)].v, p[uint(j)].v) == -1 } func (p bytesRvSlice) Swap(i, j int) { p[uint(i)], p[uint(j)] = p[uint(j)], p[uint(i)] } func (p boolRvSlice) Len() int { return len(p) } func (p boolRvSlice) Less(i, j int) bool { return !p[uint(i)].v && p[uint(j)].v } func (p boolRvSlice) Swap(i, j int) { p[uint(i)], p[uint(j)] = p[uint(j)], p[uint(i)] } func (p timeRvSlice) Len() int { return len(p) } func (p timeRvSlice) Less(i, j int) bool { return p[uint(i)].v.Before(p[uint(j)].v) } func (p timeRvSlice) Swap(i, j int) { p[uint(i)], p[uint(j)] = p[uint(j)], p[uint(i)] } // ----------------- type bytesI struct { v []byte i interface{} } type bytesISlice []bytesI func (p bytesISlice) Len() int { return len(p) } func (p bytesISlice) Less(i, j int) bool { return bytes.Compare(p[uint(i)].v, p[uint(j)].v) == -1 } func (p bytesISlice) Swap(i, j int) { p[uint(i)], p[uint(j)] = p[uint(j)], p[uint(i)] } // ----------------- type set []uintptr func (s *set) add(v uintptr) (exists bool) { // e.ci is always nil, or len >= 1 x := *s if x == nil { x = make([]uintptr, 1, 8) x[0] = v *s = x return } // typically, length will be 1. make this perform. if len(x) == 1 { if j := x[0]; j == 0 { x[0] = v } else if j == v { exists = true } else { x = append(x, v) *s = x } return } // check if it exists for _, j := range x { if j == v { exists = true return } } // try to replace a "deleted" slot for i, j := range x { if j == 0 { x[i] = v return } } // if unable to replace deleted slot, just append it. x = append(x, v) *s = x return } func (s *set) remove(v uintptr) (exists bool) { x := *s if len(x) == 0 { return } if len(x) == 1 { if x[0] == v { x[0] = 0 } return } for i, j := range x { if j == v { exists = true x[i] = 0 // set it to 0, as way to delete it. // copy(x[i:], x[i+1:]) // x = x[:len(x)-1] return } } return } // ------ // bitset types are better than [256]bool, because they permit the whole // bitset array being on a single cache line and use less memory. // // Also, since pos is a byte (0-255), there's no bounds checks on indexing (cheap). // // We previously had bitset128 [16]byte, and bitset32 [4]byte, but those introduces // bounds checking, so we discarded them, and everyone uses bitset256. // // given x > 0 and n > 0 and x is exactly 2^n, then pos/x === pos>>n AND pos%x === pos&(x-1). // consequently, pos/32 === pos>>5, pos/16 === pos>>4, pos/8 === pos>>3, pos%8 == pos&7 type bitset256 [32]byte func (x *bitset256) isset(pos byte) bool { return x[pos>>3]&(1<<(pos&7)) != 0 } // func (x *bitset256) issetv(pos byte) byte { // return x[pos>>3] & (1 << (pos & 7)) // } func (x *bitset256) set(pos byte) { x[pos>>3] |= (1 << (pos & 7)) } // func (x *bitset256) unset(pos byte) { // x[pos>>3] &^= (1 << (pos & 7)) // } // type bit2set256 [64]byte // func (x *bit2set256) set(pos byte, v1, v2 bool) { // var pos2 uint8 = (pos & 3) << 1 // returning 0, 2, 4 or 6 // if v1 { // x[pos>>2] |= 1 << (pos2 + 1) // } // if v2 { // x[pos>>2] |= 1 << pos2 // } // } // func (x *bit2set256) get(pos byte) uint8 { // var pos2 uint8 = (pos & 3) << 1 // returning 0, 2, 4 or 6 // return x[pos>>2] << (6 - pos2) >> 6 // 11000000 -> 00000011 // } // ------------ type pooler struct { // function-scoped pooled resources tiload sync.Pool // for type info loading strRv8, strRv16, strRv32, strRv64, strRv128 sync.Pool // for stringRV // lifetime-scoped pooled resources // dn sync.Pool // for decNaked buf1k, buf2k, buf4k, buf8k, buf16k sync.Pool // for [N]byte } func (p *pooler) init() { p.tiload.New = func() interface{} { return new(typeInfoLoadArray) } p.strRv8.New = func() interface{} { return new([8]sfiRv) } p.strRv16.New = func() interface{} { return new([16]sfiRv) } p.strRv32.New = func() interface{} { return new([32]sfiRv) } p.strRv64.New = func() interface{} { return new([64]sfiRv) } p.strRv128.New = func() interface{} { return new([128]sfiRv) } // p.dn.New = func() interface{} { x := new(decNaked); x.init(); return x } p.buf1k.New = func() interface{} { return new([1 * 1024]byte) } p.buf2k.New = func() interface{} { return new([2 * 1024]byte) } p.buf4k.New = func() interface{} { return new([4 * 1024]byte) } p.buf8k.New = func() interface{} { return new([8 * 1024]byte) } p.buf16k.New = func() interface{} { return new([16 * 1024]byte) } } func (p *pooler) sfiRv8() (sp *sync.Pool, v interface{}) { return &p.strRv8, p.strRv8.Get() } func (p *pooler) sfiRv16() (sp *sync.Pool, v interface{}) { return &p.strRv16, p.strRv16.Get() } func (p *pooler) sfiRv32() (sp *sync.Pool, v interface{}) { return &p.strRv32, p.strRv32.Get() } func (p *pooler) sfiRv64() (sp *sync.Pool, v interface{}) { return &p.strRv64, p.strRv64.Get() } func (p *pooler) sfiRv128() (sp *sync.Pool, v interface{}) { return &p.strRv128, p.strRv128.Get() } func (p *pooler) bytes1k() (sp *sync.Pool, v interface{}) { return &p.buf1k, p.buf1k.Get() } func (p *pooler) bytes2k() (sp *sync.Pool, v interface{}) { return &p.buf2k, p.buf2k.Get() } func (p *pooler) bytes4k() (sp *sync.Pool, v interface{}) { return &p.buf4k, p.buf4k.Get() } func (p *pooler) bytes8k() (sp *sync.Pool, v interface{}) { return &p.buf8k, p.buf8k.Get() } func (p *pooler) bytes16k() (sp *sync.Pool, v interface{}) { return &p.buf16k, p.buf16k.Get() } func (p *pooler) tiLoad() (sp *sync.Pool, v interface{}) { return &p.tiload, p.tiload.Get() } // func (p *pooler) decNaked() (sp *sync.Pool, v interface{}) { // return &p.dn, p.dn.Get() // } // func (p *pooler) decNaked() (v *decNaked, f func(*decNaked) ) { // sp := &(p.dn) // vv := sp.Get() // return vv.(*decNaked), func(x *decNaked) { sp.Put(vv) } // } // func (p *pooler) decNakedGet() (v interface{}) { // return p.dn.Get() // } // func (p *pooler) tiLoadGet() (v interface{}) { // return p.tiload.Get() // } // func (p *pooler) decNakedPut(v interface{}) { // p.dn.Put(v) // } // func (p *pooler) tiLoadPut(v interface{}) { // p.tiload.Put(v) // } // ---------------------------------------------------- type panicHdl struct{} func (panicHdl) errorv(err error) { if err != nil { panic(err) } } func (panicHdl) errorstr(message string) { if message != "" { panic(message) } } func (panicHdl) errorf(format string, params ...interface{}) { if format == "" { } else if len(params) == 0 { panic(format) } else { panic(fmt.Sprintf(format, params...)) } } // ---------------------------------------------------- type errDecorator interface { wrapErr(in interface{}, out *error) } type errDecoratorDef struct{} func (errDecoratorDef) wrapErr(v interface{}, e *error) { *e = fmt.Errorf("%v", v) } // ---------------------------------------------------- type must struct{} func (must) String(s string, err error) string { if err != nil { panicv.errorv(err) } return s } func (must) Int(s int64, err error) int64 { if err != nil { panicv.errorv(err) } return s } func (must) Uint(s uint64, err error) uint64 { if err != nil { panicv.errorv(err) } return s } func (must) Float(s float64, err error) float64 { if err != nil { panicv.errorv(err) } return s } // ------------------- type bytesBufPooler struct { pool *sync.Pool poolbuf interface{} } func (z *bytesBufPooler) end() { if z.pool != nil { z.pool.Put(z.poolbuf) z.pool, z.poolbuf = nil, nil } } func (z *bytesBufPooler) get(bufsize int) (buf []byte) { if bufsize <= 1*1024 { z.pool, z.poolbuf = pool.bytes1k() buf = z.poolbuf.(*[1 * 1024]byte)[:] } else if bufsize <= 2*1024 { z.pool, z.poolbuf = pool.bytes2k() buf = z.poolbuf.(*[2 * 1024]byte)[:] } else if bufsize <= 4*1024 { z.pool, z.poolbuf = pool.bytes4k() buf = z.poolbuf.(*[4 * 1024]byte)[:] } else if bufsize <= 8*1024 { z.pool, z.poolbuf = pool.bytes8k() buf = z.poolbuf.(*[8 * 1024]byte)[:] } else { z.pool, z.poolbuf = pool.bytes16k() buf = z.poolbuf.(*[16 * 1024]byte)[:] } return } // xdebugf prints the message in red on the terminal. // Use it in place of fmt.Printf (which it calls internally) func xdebugf(pattern string, args ...interface{}) { var delim string if len(pattern) > 0 && pattern[len(pattern)-1] != '\n' { delim = "\n" } fmt.Printf("\033[1;31m"+pattern+delim+"\033[0m", args...) } // func isImmutableKind(k reflect.Kind) (v bool) { // return false || // k == reflect.Int || // k == reflect.Int8 || // k == reflect.Int16 || // k == reflect.Int32 || // k == reflect.Int64 || // k == reflect.Uint || // k == reflect.Uint8 || // k == reflect.Uint16 || // k == reflect.Uint32 || // k == reflect.Uint64 || // k == reflect.Uintptr || // k == reflect.Float32 || // k == reflect.Float64 || // k == reflect.Bool || // k == reflect.String // } // func timeLocUTCName(tzint int16) string { // if tzint == 0 { // return "UTC" // } // var tzname = []byte("UTC+00:00") // //tzname := fmt.Sprintf("UTC%s%02d:%02d", tzsign, tz/60, tz%60) //perf issue using Sprintf. inline below. // //tzhr, tzmin := tz/60, tz%60 //faster if u convert to int first // var tzhr, tzmin int16 // if tzint < 0 { // tzname[3] = '-' // (TODO: verify. this works here) // tzhr, tzmin = -tzint/60, (-tzint)%60 // } else { // tzhr, tzmin = tzint/60, tzint%60 // } // tzname[4] = timeDigits[tzhr/10] // tzname[5] = timeDigits[tzhr%10] // tzname[7] = timeDigits[tzmin/10] // tzname[8] = timeDigits[tzmin%10] // return string(tzname) // //return time.FixedZone(string(tzname), int(tzint)*60) // }