2557 lines
62 KiB
Go
2557 lines
62 KiB
Go
// Copyright (c) 2012-2018 Ugorji Nwoke. All rights reserved.
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// Use of this source code is governed by a MIT license found in the LICENSE file.
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package codec
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import (
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"encoding"
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"errors"
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"fmt"
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"io"
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"reflect"
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"strconv"
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"sync"
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"time"
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)
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// Some tagging information for error messages.
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const (
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msgBadDesc = "unrecognized descriptor byte"
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msgDecCannotExpandArr = "cannot expand go array from %v to stream length: %v"
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)
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const decDefSliceCap = 8
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const decDefChanCap = 64 // should be large, as cap cannot be expanded
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const decScratchByteArrayLen = cacheLineSize - 8
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var (
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errstrOnlyMapOrArrayCanDecodeIntoStruct = "only encoded map or array can be decoded into a struct"
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errstrCannotDecodeIntoNil = "cannot decode into nil"
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errmsgExpandSliceOverflow = "expand slice: slice overflow"
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errmsgExpandSliceCannotChange = "expand slice: cannot change"
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errDecoderNotInitialized = errors.New("Decoder not initialized")
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errDecUnreadByteNothingToRead = errors.New("cannot unread - nothing has been read")
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errDecUnreadByteLastByteNotRead = errors.New("cannot unread - last byte has not been read")
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errDecUnreadByteUnknown = errors.New("cannot unread - reason unknown")
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)
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// decReader abstracts the reading source, allowing implementations that can
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// read from an io.Reader or directly off a byte slice with zero-copying.
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type decReader interface {
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unreadn1()
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// readx will use the implementation scratch buffer if possible i.e. n < len(scratchbuf), OR
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// just return a view of the []byte being decoded from.
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// Ensure you call detachZeroCopyBytes later if this needs to be sent outside codec control.
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readx(n int) []byte
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readb([]byte)
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readn1() uint8
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numread() int // number of bytes read
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track()
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stopTrack() []byte
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// skip will skip any byte that matches, and return the first non-matching byte
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skip(accept *bitset256) (token byte)
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// readTo will read any byte that matches, stopping once no-longer matching.
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readTo(in []byte, accept *bitset256) (out []byte)
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// readUntil will read, only stopping once it matches the 'stop' byte.
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readUntil(in []byte, stop byte) (out []byte)
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}
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type decDriver interface {
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// this will check if the next token is a break.
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CheckBreak() bool
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// Note: TryDecodeAsNil should be careful not to share any temporary []byte with
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// the rest of the decDriver. This is because sometimes, we optimize by holding onto
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// a transient []byte, and ensuring the only other call we make to the decDriver
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// during that time is maybe a TryDecodeAsNil() call.
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TryDecodeAsNil() bool
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// vt is one of: Bytes, String, Nil, Slice or Map. Return unSet if not known.
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ContainerType() (vt valueType)
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// IsBuiltinType(rt uintptr) bool
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// DecodeNaked will decode primitives (number, bool, string, []byte) and RawExt.
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// For maps and arrays, it will not do the decoding in-band, but will signal
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// the decoder, so that is done later, by setting the decNaked.valueType field.
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//
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// Note: Numbers are decoded as int64, uint64, float64 only (no smaller sized number types).
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// for extensions, DecodeNaked must read the tag and the []byte if it exists.
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// if the []byte is not read, then kInterfaceNaked will treat it as a Handle
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// that stores the subsequent value in-band, and complete reading the RawExt.
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//
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// extensions should also use readx to decode them, for efficiency.
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// kInterface will extract the detached byte slice if it has to pass it outside its realm.
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DecodeNaked()
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// Deprecated: use DecodeInt64 and DecodeUint64 instead
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// DecodeInt(bitsize uint8) (i int64)
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// DecodeUint(bitsize uint8) (ui uint64)
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DecodeInt64() (i int64)
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DecodeUint64() (ui uint64)
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DecodeFloat64() (f float64)
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DecodeBool() (b bool)
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// DecodeString can also decode symbols.
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// It looks redundant as DecodeBytes is available.
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// However, some codecs (e.g. binc) support symbols and can
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// return a pre-stored string value, meaning that it can bypass
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// the cost of []byte->string conversion.
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DecodeString() (s string)
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DecodeStringAsBytes() (v []byte)
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// DecodeBytes may be called directly, without going through reflection.
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// Consequently, it must be designed to handle possible nil.
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DecodeBytes(bs []byte, zerocopy bool) (bsOut []byte)
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// DecodeBytes(bs []byte, isstring, zerocopy bool) (bsOut []byte)
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// decodeExt will decode into a *RawExt or into an extension.
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DecodeExt(v interface{}, xtag uint64, ext Ext) (realxtag uint64)
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// decodeExt(verifyTag bool, tag byte) (xtag byte, xbs []byte)
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DecodeTime() (t time.Time)
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ReadArrayStart() int
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ReadArrayElem()
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ReadArrayEnd()
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ReadMapStart() int
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ReadMapElemKey()
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ReadMapElemValue()
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ReadMapEnd()
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reset()
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uncacheRead()
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}
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type decDriverNoopContainerReader struct{}
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func (x decDriverNoopContainerReader) ReadArrayStart() (v int) { return }
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func (x decDriverNoopContainerReader) ReadArrayElem() {}
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func (x decDriverNoopContainerReader) ReadArrayEnd() {}
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func (x decDriverNoopContainerReader) ReadMapStart() (v int) { return }
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func (x decDriverNoopContainerReader) ReadMapElemKey() {}
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func (x decDriverNoopContainerReader) ReadMapElemValue() {}
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func (x decDriverNoopContainerReader) ReadMapEnd() {}
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func (x decDriverNoopContainerReader) CheckBreak() (v bool) { return }
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// func (x decNoSeparator) uncacheRead() {}
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// DecodeOptions captures configuration options during decode.
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type DecodeOptions struct {
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// MapType specifies type to use during schema-less decoding of a map in the stream.
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// If nil (unset), we default to map[string]interface{} iff json handle and MapStringAsKey=true,
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// else map[interface{}]interface{}.
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MapType reflect.Type
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// SliceType specifies type to use during schema-less decoding of an array in the stream.
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// If nil (unset), we default to []interface{} for all formats.
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SliceType reflect.Type
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// MaxInitLen defines the maxinum initial length that we "make" a collection
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// (string, slice, map, chan). If 0 or negative, we default to a sensible value
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// based on the size of an element in the collection.
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//
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// For example, when decoding, a stream may say that it has 2^64 elements.
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// We should not auto-matically provision a slice of that size, to prevent Out-Of-Memory crash.
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// Instead, we provision up to MaxInitLen, fill that up, and start appending after that.
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MaxInitLen int
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// ReaderBufferSize is the size of the buffer used when reading.
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//
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// if > 0, we use a smart buffer internally for performance purposes.
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ReaderBufferSize int
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// If ErrorIfNoField, return an error when decoding a map
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// from a codec stream into a struct, and no matching struct field is found.
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ErrorIfNoField bool
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// If ErrorIfNoArrayExpand, return an error when decoding a slice/array that cannot be expanded.
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// For example, the stream contains an array of 8 items, but you are decoding into a [4]T array,
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// or you are decoding into a slice of length 4 which is non-addressable (and so cannot be set).
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ErrorIfNoArrayExpand bool
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// If SignedInteger, use the int64 during schema-less decoding of unsigned values (not uint64).
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SignedInteger bool
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// MapValueReset controls how we decode into a map value.
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//
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// By default, we MAY retrieve the mapping for a key, and then decode into that.
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// However, especially with big maps, that retrieval may be expensive and unnecessary
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// if the stream already contains all that is necessary to recreate the value.
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//
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// If true, we will never retrieve the previous mapping,
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// but rather decode into a new value and set that in the map.
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//
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// If false, we will retrieve the previous mapping if necessary e.g.
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// the previous mapping is a pointer, or is a struct or array with pre-set state,
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// or is an interface.
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MapValueReset bool
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// SliceElementReset: on decoding a slice, reset the element to a zero value first.
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//
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// concern: if the slice already contained some garbage, we will decode into that garbage.
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SliceElementReset bool
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// InterfaceReset controls how we decode into an interface.
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//
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// By default, when we see a field that is an interface{...},
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// or a map with interface{...} value, we will attempt decoding into the
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// "contained" value.
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//
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// However, this prevents us from reading a string into an interface{}
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// that formerly contained a number.
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//
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// If true, we will decode into a new "blank" value, and set that in the interface.
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// If false, we will decode into whatever is contained in the interface.
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InterfaceReset bool
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// InternString controls interning of strings during decoding.
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//
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// Some handles, e.g. json, typically will read map keys as strings.
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// If the set of keys are finite, it may help reduce allocation to
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// look them up from a map (than to allocate them afresh).
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//
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// Note: Handles will be smart when using the intern functionality.
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// Every string should not be interned.
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// An excellent use-case for interning is struct field names,
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// or map keys where key type is string.
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InternString bool
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// PreferArrayOverSlice controls whether to decode to an array or a slice.
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//
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// This only impacts decoding into a nil interface{}.
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// Consequently, it has no effect on codecgen.
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//
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// *Note*: This only applies if using go1.5 and above,
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// as it requires reflect.ArrayOf support which was absent before go1.5.
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PreferArrayOverSlice bool
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// DeleteOnNilMapValue controls how to decode a nil value in the stream.
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//
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// If true, we will delete the mapping of the key.
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// Else, just set the mapping to the zero value of the type.
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DeleteOnNilMapValue bool
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}
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// ------------------------------------
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type bufioDecReader struct {
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buf []byte
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r io.Reader
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c int // cursor
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n int // num read
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err error
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tr []byte
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trb bool
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b [4]byte
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}
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func (z *bufioDecReader) reset(r io.Reader) {
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z.r, z.c, z.n, z.err, z.trb = r, 0, 0, nil, false
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if z.tr != nil {
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z.tr = z.tr[:0]
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}
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}
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func (z *bufioDecReader) Read(p []byte) (n int, err error) {
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if z.err != nil {
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return 0, z.err
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}
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p0 := p
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n = copy(p, z.buf[z.c:])
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z.c += n
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if z.c == len(z.buf) {
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z.c = 0
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}
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z.n += n
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if len(p) == n {
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if z.c == 0 {
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z.buf = z.buf[:1]
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z.buf[0] = p[len(p)-1]
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z.c = 1
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}
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if z.trb {
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z.tr = append(z.tr, p0[:n]...)
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}
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return
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}
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p = p[n:]
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var n2 int
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// if we are here, then z.buf is all read
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if len(p) > len(z.buf) {
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n2, err = decReadFull(z.r, p)
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n += n2
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z.n += n2
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z.err = err
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// don't return EOF if some bytes were read. keep for next time.
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if n > 0 && err == io.EOF {
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err = nil
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}
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// always keep last byte in z.buf
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z.buf = z.buf[:1]
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z.buf[0] = p[len(p)-1]
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z.c = 1
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if z.trb {
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z.tr = append(z.tr, p0[:n]...)
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}
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return
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}
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// z.c is now 0, and len(p) <= len(z.buf)
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for len(p) > 0 && z.err == nil {
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// println("len(p) loop starting ... ")
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z.c = 0
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z.buf = z.buf[0:cap(z.buf)]
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n2, err = z.r.Read(z.buf)
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if n2 > 0 {
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if err == io.EOF {
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err = nil
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}
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z.buf = z.buf[:n2]
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n2 = copy(p, z.buf)
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z.c = n2
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n += n2
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z.n += n2
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p = p[n2:]
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}
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z.err = err
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// println("... len(p) loop done")
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}
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if z.c == 0 {
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z.buf = z.buf[:1]
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z.buf[0] = p[len(p)-1]
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z.c = 1
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}
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if z.trb {
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z.tr = append(z.tr, p0[:n]...)
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}
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return
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}
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func (z *bufioDecReader) ReadByte() (b byte, err error) {
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z.b[0] = 0
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_, err = z.Read(z.b[:1])
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b = z.b[0]
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return
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}
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func (z *bufioDecReader) UnreadByte() (err error) {
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if z.err != nil {
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return z.err
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}
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if z.c > 0 {
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z.c--
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z.n--
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if z.trb {
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z.tr = z.tr[:len(z.tr)-1]
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}
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return
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}
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return errDecUnreadByteNothingToRead
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}
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func (z *bufioDecReader) numread() int {
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return z.n
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}
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func (z *bufioDecReader) readx(n int) (bs []byte) {
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if n <= 0 || z.err != nil {
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return
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}
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if z.c+n <= len(z.buf) {
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bs = z.buf[z.c : z.c+n]
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z.n += n
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z.c += n
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if z.trb {
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z.tr = append(z.tr, bs...)
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}
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return
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}
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bs = make([]byte, n)
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_, err := z.Read(bs)
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if err != nil {
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panic(err)
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}
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return
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}
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func (z *bufioDecReader) readb(bs []byte) {
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_, err := z.Read(bs)
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if err != nil {
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panic(err)
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}
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}
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// func (z *bufioDecReader) readn1eof() (b uint8, eof bool) {
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// b, err := z.ReadByte()
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// if err != nil {
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// if err == io.EOF {
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// eof = true
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// } else {
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// panic(err)
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// }
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// }
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// return
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// }
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func (z *bufioDecReader) readn1() (b uint8) {
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b, err := z.ReadByte()
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if err != nil {
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panic(err)
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}
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return
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}
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func (z *bufioDecReader) search(in []byte, accept *bitset256, stop, flag uint8) (token byte, out []byte) {
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// flag: 1 (skip), 2 (readTo), 4 (readUntil)
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if flag == 4 {
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for i := z.c; i < len(z.buf); i++ {
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if z.buf[i] == stop {
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token = z.buf[i]
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z.n = z.n + (i - z.c) - 1
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i++
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out = z.buf[z.c:i]
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if z.trb {
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z.tr = append(z.tr, z.buf[z.c:i]...)
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}
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z.c = i
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return
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}
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}
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} else {
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for i := z.c; i < len(z.buf); i++ {
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if !accept.isset(z.buf[i]) {
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token = z.buf[i]
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z.n = z.n + (i - z.c) - 1
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if flag == 1 {
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i++
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} else {
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out = z.buf[z.c:i]
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}
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if z.trb {
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z.tr = append(z.tr, z.buf[z.c:i]...)
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}
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z.c = i
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return
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}
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}
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}
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z.n += len(z.buf) - z.c
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if flag != 1 {
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out = append(in, z.buf[z.c:]...)
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}
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if z.trb {
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z.tr = append(z.tr, z.buf[z.c:]...)
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}
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var n2 int
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if z.err != nil {
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return
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}
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for {
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z.c = 0
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z.buf = z.buf[0:cap(z.buf)]
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n2, z.err = z.r.Read(z.buf)
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if n2 > 0 && z.err != nil {
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z.err = nil
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}
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z.buf = z.buf[:n2]
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if flag == 4 {
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for i := 0; i < n2; i++ {
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if z.buf[i] == stop {
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token = z.buf[i]
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z.n += i - 1
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i++
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out = append(out, z.buf[z.c:i]...)
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if z.trb {
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z.tr = append(z.tr, z.buf[z.c:i]...)
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}
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z.c = i
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return
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}
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}
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} else {
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for i := 0; i < n2; i++ {
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if !accept.isset(z.buf[i]) {
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token = z.buf[i]
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z.n += i - 1
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if flag == 1 {
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i++
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}
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if flag != 1 {
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out = append(out, z.buf[z.c:i]...)
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}
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if z.trb {
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z.tr = append(z.tr, z.buf[z.c:i]...)
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}
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z.c = i
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return
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}
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}
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}
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if flag != 1 {
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out = append(out, z.buf[:n2]...)
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}
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z.n += n2
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if z.err != nil {
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return
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}
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if z.trb {
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z.tr = append(z.tr, z.buf[:n2]...)
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}
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}
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}
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func (z *bufioDecReader) skip(accept *bitset256) (token byte) {
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token, _ = z.search(nil, accept, 0, 1)
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return
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}
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func (z *bufioDecReader) readTo(in []byte, accept *bitset256) (out []byte) {
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_, out = z.search(in, accept, 0, 2)
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return
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|
}
|
|
|
|
func (z *bufioDecReader) readUntil(in []byte, stop byte) (out []byte) {
|
|
_, out = z.search(in, nil, stop, 4)
|
|
return
|
|
}
|
|
|
|
func (z *bufioDecReader) unreadn1() {
|
|
err := z.UnreadByte()
|
|
if err != nil {
|
|
panic(err)
|
|
}
|
|
}
|
|
|
|
func (z *bufioDecReader) track() {
|
|
if z.tr != nil {
|
|
z.tr = z.tr[:0]
|
|
}
|
|
z.trb = true
|
|
}
|
|
|
|
func (z *bufioDecReader) stopTrack() (bs []byte) {
|
|
z.trb = false
|
|
return z.tr
|
|
}
|
|
|
|
// ioDecReader is a decReader that reads off an io.Reader.
|
|
//
|
|
// It also has a fallback implementation of ByteScanner if needed.
|
|
type ioDecReader struct {
|
|
r io.Reader // the reader passed in
|
|
|
|
rr io.Reader
|
|
br io.ByteScanner
|
|
|
|
l byte // last byte
|
|
ls byte // last byte status. 0: init-canDoNothing, 1: canRead, 2: canUnread
|
|
trb bool // tracking bytes turned on
|
|
_ bool
|
|
b [4]byte // tiny buffer for reading single bytes
|
|
|
|
x [scratchByteArrayLen]byte // for: get struct field name, swallow valueTypeBytes, etc
|
|
n int // num read
|
|
tr []byte // tracking bytes read
|
|
}
|
|
|
|
func (z *ioDecReader) reset(r io.Reader) {
|
|
z.r = r
|
|
z.rr = r
|
|
z.l, z.ls, z.n, z.trb = 0, 0, 0, false
|
|
if z.tr != nil {
|
|
z.tr = z.tr[:0]
|
|
}
|
|
var ok bool
|
|
if z.br, ok = r.(io.ByteScanner); !ok {
|
|
z.br = z
|
|
z.rr = z
|
|
}
|
|
}
|
|
|
|
func (z *ioDecReader) Read(p []byte) (n int, err error) {
|
|
if len(p) == 0 {
|
|
return
|
|
}
|
|
var firstByte bool
|
|
if z.ls == 1 {
|
|
z.ls = 2
|
|
p[0] = z.l
|
|
if len(p) == 1 {
|
|
n = 1
|
|
return
|
|
}
|
|
firstByte = true
|
|
p = p[1:]
|
|
}
|
|
n, err = z.r.Read(p)
|
|
if n > 0 {
|
|
if err == io.EOF && n == len(p) {
|
|
err = nil // read was successful, so postpone EOF (till next time)
|
|
}
|
|
z.l = p[n-1]
|
|
z.ls = 2
|
|
}
|
|
if firstByte {
|
|
n++
|
|
}
|
|
return
|
|
}
|
|
|
|
func (z *ioDecReader) ReadByte() (c byte, err error) {
|
|
n, err := z.Read(z.b[:1])
|
|
if n == 1 {
|
|
c = z.b[0]
|
|
if err == io.EOF {
|
|
err = nil // read was successful, so postpone EOF (till next time)
|
|
}
|
|
}
|
|
return
|
|
}
|
|
|
|
func (z *ioDecReader) UnreadByte() (err error) {
|
|
switch z.ls {
|
|
case 2:
|
|
z.ls = 1
|
|
case 0:
|
|
err = errDecUnreadByteNothingToRead
|
|
case 1:
|
|
err = errDecUnreadByteLastByteNotRead
|
|
default:
|
|
err = errDecUnreadByteUnknown
|
|
}
|
|
return
|
|
}
|
|
|
|
func (z *ioDecReader) numread() int {
|
|
return z.n
|
|
}
|
|
|
|
func (z *ioDecReader) readx(n int) (bs []byte) {
|
|
if n <= 0 {
|
|
return
|
|
}
|
|
if n < len(z.x) {
|
|
bs = z.x[:n]
|
|
} else {
|
|
bs = make([]byte, n)
|
|
}
|
|
if _, err := decReadFull(z.rr, bs); err != nil {
|
|
panic(err)
|
|
}
|
|
z.n += len(bs)
|
|
if z.trb {
|
|
z.tr = append(z.tr, bs...)
|
|
}
|
|
return
|
|
}
|
|
|
|
func (z *ioDecReader) readb(bs []byte) {
|
|
// if len(bs) == 0 {
|
|
// return
|
|
// }
|
|
if _, err := decReadFull(z.rr, bs); err != nil {
|
|
panic(err)
|
|
}
|
|
z.n += len(bs)
|
|
if z.trb {
|
|
z.tr = append(z.tr, bs...)
|
|
}
|
|
}
|
|
|
|
func (z *ioDecReader) readn1eof() (b uint8, eof bool) {
|
|
b, err := z.br.ReadByte()
|
|
if err == nil {
|
|
z.n++
|
|
if z.trb {
|
|
z.tr = append(z.tr, b)
|
|
}
|
|
} else if err == io.EOF {
|
|
eof = true
|
|
} else {
|
|
panic(err)
|
|
}
|
|
return
|
|
}
|
|
|
|
func (z *ioDecReader) readn1() (b uint8) {
|
|
var err error
|
|
if b, err = z.br.ReadByte(); err == nil {
|
|
z.n++
|
|
if z.trb {
|
|
z.tr = append(z.tr, b)
|
|
}
|
|
return
|
|
}
|
|
panic(err)
|
|
}
|
|
|
|
func (z *ioDecReader) skip(accept *bitset256) (token byte) {
|
|
for {
|
|
var eof bool
|
|
token, eof = z.readn1eof()
|
|
if eof {
|
|
return
|
|
}
|
|
if accept.isset(token) {
|
|
continue
|
|
}
|
|
return
|
|
}
|
|
}
|
|
|
|
func (z *ioDecReader) readTo(in []byte, accept *bitset256) (out []byte) {
|
|
out = in
|
|
for {
|
|
token, eof := z.readn1eof()
|
|
if eof {
|
|
return
|
|
}
|
|
if accept.isset(token) {
|
|
out = append(out, token)
|
|
} else {
|
|
z.unreadn1()
|
|
return
|
|
}
|
|
}
|
|
}
|
|
|
|
func (z *ioDecReader) readUntil(in []byte, stop byte) (out []byte) {
|
|
out = in
|
|
for {
|
|
token, eof := z.readn1eof()
|
|
if eof {
|
|
panic(io.EOF)
|
|
}
|
|
out = append(out, token)
|
|
if token == stop {
|
|
return
|
|
}
|
|
}
|
|
}
|
|
|
|
func (z *ioDecReader) unreadn1() {
|
|
err := z.br.UnreadByte()
|
|
if err != nil {
|
|
panic(err)
|
|
}
|
|
z.n--
|
|
if z.trb {
|
|
if l := len(z.tr) - 1; l >= 0 {
|
|
z.tr = z.tr[:l]
|
|
}
|
|
}
|
|
}
|
|
|
|
func (z *ioDecReader) track() {
|
|
if z.tr != nil {
|
|
z.tr = z.tr[:0]
|
|
}
|
|
z.trb = true
|
|
}
|
|
|
|
func (z *ioDecReader) stopTrack() (bs []byte) {
|
|
z.trb = false
|
|
return z.tr
|
|
}
|
|
|
|
// ------------------------------------
|
|
|
|
var errBytesDecReaderCannotUnread = errors.New("cannot unread last byte read")
|
|
|
|
// bytesDecReader is a decReader that reads off a byte slice with zero copying
|
|
type bytesDecReader struct {
|
|
b []byte // data
|
|
c int // cursor
|
|
a int // available
|
|
t int // track start
|
|
}
|
|
|
|
func (z *bytesDecReader) reset(in []byte) {
|
|
z.b = in
|
|
z.a = len(in)
|
|
z.c = 0
|
|
z.t = 0
|
|
}
|
|
|
|
func (z *bytesDecReader) numread() int {
|
|
return z.c
|
|
}
|
|
|
|
func (z *bytesDecReader) unreadn1() {
|
|
if z.c == 0 || len(z.b) == 0 {
|
|
panic(errBytesDecReaderCannotUnread)
|
|
}
|
|
z.c--
|
|
z.a++
|
|
return
|
|
}
|
|
|
|
func (z *bytesDecReader) readx(n int) (bs []byte) {
|
|
// slicing from a non-constant start position is more expensive,
|
|
// as more computation is required to decipher the pointer start position.
|
|
// However, we do it only once, and it's better than reslicing both z.b and return value.
|
|
|
|
if n <= 0 {
|
|
} else if z.a == 0 {
|
|
panic(io.EOF)
|
|
} else if n > z.a {
|
|
panic(io.ErrUnexpectedEOF)
|
|
} else {
|
|
c0 := z.c
|
|
z.c = c0 + n
|
|
z.a = z.a - n
|
|
bs = z.b[c0:z.c]
|
|
}
|
|
return
|
|
}
|
|
|
|
func (z *bytesDecReader) readb(bs []byte) {
|
|
copy(bs, z.readx(len(bs)))
|
|
}
|
|
|
|
func (z *bytesDecReader) readn1() (v uint8) {
|
|
if z.a == 0 {
|
|
panic(io.EOF)
|
|
}
|
|
v = z.b[z.c]
|
|
z.c++
|
|
z.a--
|
|
return
|
|
}
|
|
|
|
// func (z *bytesDecReader) readn1eof() (v uint8, eof bool) {
|
|
// if z.a == 0 {
|
|
// eof = true
|
|
// return
|
|
// }
|
|
// v = z.b[z.c]
|
|
// z.c++
|
|
// z.a--
|
|
// return
|
|
// }
|
|
|
|
func (z *bytesDecReader) skip(accept *bitset256) (token byte) {
|
|
if z.a == 0 {
|
|
return
|
|
}
|
|
blen := len(z.b)
|
|
for i := z.c; i < blen; i++ {
|
|
if !accept.isset(z.b[i]) {
|
|
token = z.b[i]
|
|
i++
|
|
z.a -= (i - z.c)
|
|
z.c = i
|
|
return
|
|
}
|
|
}
|
|
z.a, z.c = 0, blen
|
|
return
|
|
}
|
|
|
|
func (z *bytesDecReader) readTo(_ []byte, accept *bitset256) (out []byte) {
|
|
if z.a == 0 {
|
|
return
|
|
}
|
|
blen := len(z.b)
|
|
for i := z.c; i < blen; i++ {
|
|
if !accept.isset(z.b[i]) {
|
|
out = z.b[z.c:i]
|
|
z.a -= (i - z.c)
|
|
z.c = i
|
|
return
|
|
}
|
|
}
|
|
out = z.b[z.c:]
|
|
z.a, z.c = 0, blen
|
|
return
|
|
}
|
|
|
|
func (z *bytesDecReader) readUntil(_ []byte, stop byte) (out []byte) {
|
|
if z.a == 0 {
|
|
panic(io.EOF)
|
|
}
|
|
blen := len(z.b)
|
|
for i := z.c; i < blen; i++ {
|
|
if z.b[i] == stop {
|
|
i++
|
|
out = z.b[z.c:i]
|
|
z.a -= (i - z.c)
|
|
z.c = i
|
|
return
|
|
}
|
|
}
|
|
z.a, z.c = 0, blen
|
|
panic(io.EOF)
|
|
}
|
|
|
|
func (z *bytesDecReader) track() {
|
|
z.t = z.c
|
|
}
|
|
|
|
func (z *bytesDecReader) stopTrack() (bs []byte) {
|
|
return z.b[z.t:z.c]
|
|
}
|
|
|
|
// ----------------------------------------
|
|
|
|
// func (d *Decoder) builtin(f *codecFnInfo, rv reflect.Value) {
|
|
// d.d.DecodeBuiltin(f.ti.rtid, rv2i(rv))
|
|
// }
|
|
|
|
func (d *Decoder) rawExt(f *codecFnInfo, rv reflect.Value) {
|
|
d.d.DecodeExt(rv2i(rv), 0, nil)
|
|
}
|
|
|
|
func (d *Decoder) ext(f *codecFnInfo, rv reflect.Value) {
|
|
d.d.DecodeExt(rv2i(rv), f.xfTag, f.xfFn)
|
|
}
|
|
|
|
func (d *Decoder) selferUnmarshal(f *codecFnInfo, rv reflect.Value) {
|
|
rv2i(rv).(Selfer).CodecDecodeSelf(d)
|
|
}
|
|
|
|
func (d *Decoder) binaryUnmarshal(f *codecFnInfo, rv reflect.Value) {
|
|
bm := rv2i(rv).(encoding.BinaryUnmarshaler)
|
|
xbs := d.d.DecodeBytes(nil, true)
|
|
if fnerr := bm.UnmarshalBinary(xbs); fnerr != nil {
|
|
panic(fnerr)
|
|
}
|
|
}
|
|
|
|
func (d *Decoder) textUnmarshal(f *codecFnInfo, rv reflect.Value) {
|
|
tm := rv2i(rv).(encoding.TextUnmarshaler)
|
|
fnerr := tm.UnmarshalText(d.d.DecodeStringAsBytes())
|
|
if fnerr != nil {
|
|
panic(fnerr)
|
|
}
|
|
}
|
|
|
|
func (d *Decoder) jsonUnmarshal(f *codecFnInfo, rv reflect.Value) {
|
|
tm := rv2i(rv).(jsonUnmarshaler)
|
|
// bs := d.d.DecodeBytes(d.b[:], true, true)
|
|
// grab the bytes to be read, as UnmarshalJSON needs the full JSON so as to unmarshal it itself.
|
|
fnerr := tm.UnmarshalJSON(d.nextValueBytes())
|
|
if fnerr != nil {
|
|
panic(fnerr)
|
|
}
|
|
}
|
|
|
|
func (d *Decoder) kErr(f *codecFnInfo, rv reflect.Value) {
|
|
d.errorf("no decoding function defined for kind %v", rv.Kind())
|
|
}
|
|
|
|
// var kIntfCtr uint64
|
|
|
|
func (d *Decoder) kInterfaceNaked(f *codecFnInfo) (rvn reflect.Value) {
|
|
// nil interface:
|
|
// use some hieristics to decode it appropriately
|
|
// based on the detected next value in the stream.
|
|
n := d.naked()
|
|
d.d.DecodeNaked()
|
|
if n.v == valueTypeNil {
|
|
return
|
|
}
|
|
// We cannot decode non-nil stream value into nil interface with methods (e.g. io.Reader).
|
|
if f.ti.numMeth > 0 {
|
|
d.errorf("cannot decode non-nil codec value into nil %v (%v methods)", f.ti.rt, f.ti.numMeth)
|
|
return
|
|
}
|
|
// var useRvn bool
|
|
switch n.v {
|
|
case valueTypeMap:
|
|
// if json, default to a map type with string keys
|
|
mtid := d.mtid
|
|
if mtid == 0 {
|
|
if d.jsms {
|
|
mtid = mapStrIntfTypId
|
|
} else {
|
|
mtid = mapIntfIntfTypId
|
|
}
|
|
}
|
|
if mtid == mapIntfIntfTypId {
|
|
n.initContainers()
|
|
if n.lm < arrayCacheLen {
|
|
n.ma[n.lm] = nil
|
|
rvn = n.rma[n.lm]
|
|
n.lm++
|
|
d.decode(&n.ma[n.lm-1])
|
|
n.lm--
|
|
} else {
|
|
var v2 map[interface{}]interface{}
|
|
d.decode(&v2)
|
|
rvn = reflect.ValueOf(&v2).Elem()
|
|
}
|
|
} else if mtid == mapStrIntfTypId { // for json performance
|
|
n.initContainers()
|
|
if n.ln < arrayCacheLen {
|
|
n.na[n.ln] = nil
|
|
rvn = n.rna[n.ln]
|
|
n.ln++
|
|
d.decode(&n.na[n.ln-1])
|
|
n.ln--
|
|
} else {
|
|
var v2 map[string]interface{}
|
|
d.decode(&v2)
|
|
rvn = reflect.ValueOf(&v2).Elem()
|
|
}
|
|
} else {
|
|
if d.mtr {
|
|
rvn = reflect.New(d.h.MapType)
|
|
d.decode(rv2i(rvn))
|
|
rvn = rvn.Elem()
|
|
} else {
|
|
rvn = reflect.New(d.h.MapType).Elem()
|
|
d.decodeValue(rvn, nil, true)
|
|
}
|
|
}
|
|
case valueTypeArray:
|
|
if d.stid == 0 || d.stid == intfSliceTypId {
|
|
n.initContainers()
|
|
if n.ls < arrayCacheLen {
|
|
n.sa[n.ls] = nil
|
|
rvn = n.rsa[n.ls]
|
|
n.ls++
|
|
d.decode(&n.sa[n.ls-1])
|
|
n.ls--
|
|
} else {
|
|
var v2 []interface{}
|
|
d.decode(&v2)
|
|
rvn = reflect.ValueOf(&v2).Elem()
|
|
}
|
|
if reflectArrayOfSupported && d.stid == 0 && d.h.PreferArrayOverSlice {
|
|
rvn2 := reflect.New(reflectArrayOf(rvn.Len(), intfTyp)).Elem()
|
|
reflect.Copy(rvn2, rvn)
|
|
rvn = rvn2
|
|
}
|
|
} else {
|
|
if d.str {
|
|
rvn = reflect.New(d.h.SliceType)
|
|
d.decode(rv2i(rvn))
|
|
rvn = rvn.Elem()
|
|
} else {
|
|
rvn = reflect.New(d.h.SliceType).Elem()
|
|
d.decodeValue(rvn, nil, true)
|
|
}
|
|
}
|
|
case valueTypeExt:
|
|
var v interface{}
|
|
tag, bytes := n.u, n.l // calling decode below might taint the values
|
|
if bytes == nil {
|
|
n.initContainers()
|
|
if n.li < arrayCacheLen {
|
|
n.ia[n.li] = nil
|
|
n.li++
|
|
d.decode(&n.ia[n.li-1])
|
|
// v = *(&n.ia[l])
|
|
n.li--
|
|
v = n.ia[n.li]
|
|
n.ia[n.li] = nil
|
|
} else {
|
|
d.decode(&v)
|
|
}
|
|
}
|
|
bfn := d.h.getExtForTag(tag)
|
|
if bfn == nil {
|
|
var re RawExt
|
|
re.Tag = tag
|
|
re.Data = detachZeroCopyBytes(d.bytes, nil, bytes)
|
|
re.Value = v
|
|
rvn = reflect.ValueOf(&re).Elem()
|
|
} else {
|
|
rvnA := reflect.New(bfn.rt)
|
|
if bytes != nil {
|
|
bfn.ext.ReadExt(rv2i(rvnA), bytes)
|
|
} else {
|
|
bfn.ext.UpdateExt(rv2i(rvnA), v)
|
|
}
|
|
rvn = rvnA.Elem()
|
|
}
|
|
case valueTypeNil:
|
|
// no-op
|
|
case valueTypeInt:
|
|
rvn = n.ri
|
|
case valueTypeUint:
|
|
rvn = n.ru
|
|
case valueTypeFloat:
|
|
rvn = n.rf
|
|
case valueTypeBool:
|
|
rvn = n.rb
|
|
case valueTypeString, valueTypeSymbol:
|
|
rvn = n.rs
|
|
case valueTypeBytes:
|
|
rvn = n.rl
|
|
case valueTypeTime:
|
|
rvn = n.rt
|
|
default:
|
|
panicv.errorf("kInterfaceNaked: unexpected valueType: %d", n.v)
|
|
}
|
|
return
|
|
}
|
|
|
|
func (d *Decoder) kInterface(f *codecFnInfo, rv reflect.Value) {
|
|
// Note:
|
|
// A consequence of how kInterface works, is that
|
|
// if an interface already contains something, we try
|
|
// to decode into what was there before.
|
|
// We do not replace with a generic value (as got from decodeNaked).
|
|
|
|
// every interface passed here MUST be settable.
|
|
var rvn reflect.Value
|
|
if rv.IsNil() || d.h.InterfaceReset {
|
|
// check if mapping to a type: if so, initialize it and move on
|
|
rvn = d.h.intf2impl(f.ti.rtid)
|
|
if rvn.IsValid() {
|
|
rv.Set(rvn)
|
|
} else {
|
|
rvn = d.kInterfaceNaked(f)
|
|
if rvn.IsValid() {
|
|
rv.Set(rvn)
|
|
} else if d.h.InterfaceReset {
|
|
// reset to zero value based on current type in there.
|
|
rv.Set(reflect.Zero(rv.Elem().Type()))
|
|
}
|
|
return
|
|
}
|
|
} else {
|
|
// now we have a non-nil interface value, meaning it contains a type
|
|
rvn = rv.Elem()
|
|
}
|
|
if d.d.TryDecodeAsNil() {
|
|
rv.Set(reflect.Zero(rvn.Type()))
|
|
return
|
|
}
|
|
|
|
// Note: interface{} is settable, but underlying type may not be.
|
|
// Consequently, we MAY have to create a decodable value out of the underlying value,
|
|
// decode into it, and reset the interface itself.
|
|
// fmt.Printf(">>>> kInterface: rvn type: %v, rv type: %v\n", rvn.Type(), rv.Type())
|
|
|
|
rvn2, canDecode := isDecodeable(rvn)
|
|
if canDecode {
|
|
d.decodeValue(rvn2, nil, true)
|
|
return
|
|
}
|
|
|
|
rvn2 = reflect.New(rvn.Type()).Elem()
|
|
rvn2.Set(rvn)
|
|
d.decodeValue(rvn2, nil, true)
|
|
rv.Set(rvn2)
|
|
}
|
|
|
|
func decStructFieldKey(dd decDriver, keyType valueType, b *[decScratchByteArrayLen]byte) (rvkencname []byte) {
|
|
// use if-else-if, not switch (which compiles to binary-search)
|
|
// since keyType is typically valueTypeString, branch prediction is pretty good.
|
|
|
|
if keyType == valueTypeString {
|
|
rvkencname = dd.DecodeStringAsBytes()
|
|
} else if keyType == valueTypeInt {
|
|
rvkencname = strconv.AppendInt(b[:0], dd.DecodeInt64(), 10)
|
|
} else if keyType == valueTypeUint {
|
|
rvkencname = strconv.AppendUint(b[:0], dd.DecodeUint64(), 10)
|
|
} else if keyType == valueTypeFloat {
|
|
rvkencname = strconv.AppendFloat(b[:0], dd.DecodeFloat64(), 'f', -1, 64)
|
|
} else {
|
|
rvkencname = dd.DecodeStringAsBytes()
|
|
}
|
|
return rvkencname
|
|
}
|
|
|
|
func (d *Decoder) kStruct(f *codecFnInfo, rv reflect.Value) {
|
|
fti := f.ti
|
|
dd := d.d
|
|
elemsep := d.esep
|
|
sfn := structFieldNode{v: rv, update: true}
|
|
ctyp := dd.ContainerType()
|
|
if ctyp == valueTypeMap {
|
|
containerLen := dd.ReadMapStart()
|
|
if containerLen == 0 {
|
|
dd.ReadMapEnd()
|
|
return
|
|
}
|
|
tisfi := fti.sfiSort
|
|
hasLen := containerLen >= 0
|
|
|
|
var rvkencname []byte
|
|
for j := 0; (hasLen && j < containerLen) || !(hasLen || dd.CheckBreak()); j++ {
|
|
if elemsep {
|
|
dd.ReadMapElemKey()
|
|
}
|
|
rvkencname = decStructFieldKey(dd, fti.keyType, &d.b)
|
|
if elemsep {
|
|
dd.ReadMapElemValue()
|
|
}
|
|
if k := fti.indexForEncName(rvkencname); k > -1 {
|
|
si := tisfi[k]
|
|
if dd.TryDecodeAsNil() {
|
|
si.setToZeroValue(rv)
|
|
} else {
|
|
d.decodeValue(sfn.field(si), nil, true)
|
|
}
|
|
} else {
|
|
d.structFieldNotFound(-1, stringView(rvkencname))
|
|
}
|
|
// keepAlive4StringView(rvkencnameB) // not needed, as reference is outside loop
|
|
}
|
|
dd.ReadMapEnd()
|
|
} else if ctyp == valueTypeArray {
|
|
containerLen := dd.ReadArrayStart()
|
|
if containerLen == 0 {
|
|
dd.ReadArrayEnd()
|
|
return
|
|
}
|
|
// Not much gain from doing it two ways for array.
|
|
// Arrays are not used as much for structs.
|
|
hasLen := containerLen >= 0
|
|
for j, si := range fti.sfiSrc {
|
|
if (hasLen && j == containerLen) || (!hasLen && dd.CheckBreak()) {
|
|
break
|
|
}
|
|
if elemsep {
|
|
dd.ReadArrayElem()
|
|
}
|
|
if dd.TryDecodeAsNil() {
|
|
si.setToZeroValue(rv)
|
|
} else {
|
|
d.decodeValue(sfn.field(si), nil, true)
|
|
}
|
|
}
|
|
if containerLen > len(fti.sfiSrc) {
|
|
// read remaining values and throw away
|
|
for j := len(fti.sfiSrc); j < containerLen; j++ {
|
|
if elemsep {
|
|
dd.ReadArrayElem()
|
|
}
|
|
d.structFieldNotFound(j, "")
|
|
}
|
|
}
|
|
dd.ReadArrayEnd()
|
|
} else {
|
|
d.errorstr(errstrOnlyMapOrArrayCanDecodeIntoStruct)
|
|
return
|
|
}
|
|
}
|
|
|
|
func (d *Decoder) kSlice(f *codecFnInfo, rv reflect.Value) {
|
|
// A slice can be set from a map or array in stream.
|
|
// This way, the order can be kept (as order is lost with map).
|
|
ti := f.ti
|
|
if f.seq == seqTypeChan && ti.chandir&uint8(reflect.SendDir) == 0 {
|
|
d.errorf("receive-only channel cannot be decoded")
|
|
}
|
|
dd := d.d
|
|
rtelem0 := ti.elem
|
|
ctyp := dd.ContainerType()
|
|
if ctyp == valueTypeBytes || ctyp == valueTypeString {
|
|
// you can only decode bytes or string in the stream into a slice or array of bytes
|
|
if !(ti.rtid == uint8SliceTypId || rtelem0.Kind() == reflect.Uint8) {
|
|
d.errorf("bytes/string in stream must decode into slice/array of bytes, not %v", ti.rt)
|
|
}
|
|
if f.seq == seqTypeChan {
|
|
bs2 := dd.DecodeBytes(nil, true)
|
|
irv := rv2i(rv)
|
|
ch, ok := irv.(chan<- byte)
|
|
if !ok {
|
|
ch = irv.(chan byte)
|
|
}
|
|
for _, b := range bs2 {
|
|
ch <- b
|
|
}
|
|
} else {
|
|
rvbs := rv.Bytes()
|
|
bs2 := dd.DecodeBytes(rvbs, false)
|
|
// if rvbs == nil && bs2 != nil || rvbs != nil && bs2 == nil || len(bs2) != len(rvbs) {
|
|
if !(len(bs2) > 0 && len(bs2) == len(rvbs) && &bs2[0] == &rvbs[0]) {
|
|
if rv.CanSet() {
|
|
rv.SetBytes(bs2)
|
|
} else if len(rvbs) > 0 && len(bs2) > 0 {
|
|
copy(rvbs, bs2)
|
|
}
|
|
}
|
|
}
|
|
return
|
|
}
|
|
|
|
// array := f.seq == seqTypeChan
|
|
|
|
slh, containerLenS := d.decSliceHelperStart() // only expects valueType(Array|Map)
|
|
|
|
// an array can never return a nil slice. so no need to check f.array here.
|
|
if containerLenS == 0 {
|
|
if rv.CanSet() {
|
|
if f.seq == seqTypeSlice {
|
|
if rv.IsNil() {
|
|
rv.Set(reflect.MakeSlice(ti.rt, 0, 0))
|
|
} else {
|
|
rv.SetLen(0)
|
|
}
|
|
} else if f.seq == seqTypeChan {
|
|
if rv.IsNil() {
|
|
rv.Set(reflect.MakeChan(ti.rt, 0))
|
|
}
|
|
}
|
|
}
|
|
slh.End()
|
|
return
|
|
}
|
|
|
|
rtelem0Size := int(rtelem0.Size())
|
|
rtElem0Kind := rtelem0.Kind()
|
|
rtelem0Mut := !isImmutableKind(rtElem0Kind)
|
|
rtelem := rtelem0
|
|
rtelemkind := rtelem.Kind()
|
|
for rtelemkind == reflect.Ptr {
|
|
rtelem = rtelem.Elem()
|
|
rtelemkind = rtelem.Kind()
|
|
}
|
|
|
|
var fn *codecFn
|
|
|
|
var rvCanset = rv.CanSet()
|
|
var rvChanged bool
|
|
var rv0 = rv
|
|
var rv9 reflect.Value
|
|
|
|
rvlen := rv.Len()
|
|
rvcap := rv.Cap()
|
|
hasLen := containerLenS > 0
|
|
if hasLen && f.seq == seqTypeSlice {
|
|
if containerLenS > rvcap {
|
|
oldRvlenGtZero := rvlen > 0
|
|
rvlen = decInferLen(containerLenS, d.h.MaxInitLen, int(rtelem0.Size()))
|
|
if rvlen <= rvcap {
|
|
if rvCanset {
|
|
rv.SetLen(rvlen)
|
|
}
|
|
} else if rvCanset {
|
|
rv = reflect.MakeSlice(ti.rt, rvlen, rvlen)
|
|
rvcap = rvlen
|
|
rvChanged = true
|
|
} else {
|
|
d.errorf("cannot decode into non-settable slice")
|
|
}
|
|
if rvChanged && oldRvlenGtZero && !isImmutableKind(rtelem0.Kind()) {
|
|
reflect.Copy(rv, rv0) // only copy up to length NOT cap i.e. rv0.Slice(0, rvcap)
|
|
}
|
|
} else if containerLenS != rvlen {
|
|
rvlen = containerLenS
|
|
if rvCanset {
|
|
rv.SetLen(rvlen)
|
|
}
|
|
// else {
|
|
// rv = rv.Slice(0, rvlen)
|
|
// rvChanged = true
|
|
// d.errorf("cannot decode into non-settable slice")
|
|
// }
|
|
}
|
|
}
|
|
|
|
// consider creating new element once, and just decoding into it.
|
|
var rtelem0Zero reflect.Value
|
|
var rtelem0ZeroValid bool
|
|
var decodeAsNil bool
|
|
var j int
|
|
d.cfer()
|
|
for ; (hasLen && j < containerLenS) || !(hasLen || dd.CheckBreak()); j++ {
|
|
if j == 0 && (f.seq == seqTypeSlice || f.seq == seqTypeChan) && rv.IsNil() {
|
|
if hasLen {
|
|
rvlen = decInferLen(containerLenS, d.h.MaxInitLen, rtelem0Size)
|
|
} else if f.seq == seqTypeSlice {
|
|
rvlen = decDefSliceCap
|
|
} else {
|
|
rvlen = decDefChanCap
|
|
}
|
|
if rvCanset {
|
|
if f.seq == seqTypeSlice {
|
|
rv = reflect.MakeSlice(ti.rt, rvlen, rvlen)
|
|
rvChanged = true
|
|
} else { // chan
|
|
// xdebugf(">>>>>> haslen = %v, make chan of type '%v' with length: %v", hasLen, ti.rt, rvlen)
|
|
rv = reflect.MakeChan(ti.rt, rvlen)
|
|
rvChanged = true
|
|
}
|
|
} else {
|
|
d.errorf("cannot decode into non-settable slice")
|
|
}
|
|
}
|
|
slh.ElemContainerState(j)
|
|
decodeAsNil = dd.TryDecodeAsNil()
|
|
if f.seq == seqTypeChan {
|
|
if decodeAsNil {
|
|
rv.Send(reflect.Zero(rtelem0))
|
|
continue
|
|
}
|
|
if rtelem0Mut || !rv9.IsValid() { // || (rtElem0Kind == reflect.Ptr && rv9.IsNil()) {
|
|
rv9 = reflect.New(rtelem0).Elem()
|
|
}
|
|
if fn == nil {
|
|
fn = d.cf.get(rtelem, true, true)
|
|
}
|
|
d.decodeValue(rv9, fn, true)
|
|
// xdebugf(">>>> rv9 sent on %v during decode: %v, with len=%v, cap=%v", rv.Type(), rv9, rv.Len(), rv.Cap())
|
|
rv.Send(rv9)
|
|
} else {
|
|
// if indefinite, etc, then expand the slice if necessary
|
|
var decodeIntoBlank bool
|
|
if j >= rvlen {
|
|
if f.seq == seqTypeArray {
|
|
d.arrayCannotExpand(rvlen, j+1)
|
|
decodeIntoBlank = true
|
|
} else { // if f.seq == seqTypeSlice
|
|
// rv = reflect.Append(rv, reflect.Zero(rtelem0)) // append logic + varargs
|
|
var rvcap2 int
|
|
var rvErrmsg2 string
|
|
rv9, rvcap2, rvChanged, rvErrmsg2 =
|
|
expandSliceRV(rv, ti.rt, rvCanset, rtelem0Size, 1, rvlen, rvcap)
|
|
if rvErrmsg2 != "" {
|
|
d.errorf(rvErrmsg2)
|
|
}
|
|
rvlen++
|
|
if rvChanged {
|
|
rv = rv9
|
|
rvcap = rvcap2
|
|
}
|
|
}
|
|
}
|
|
if decodeIntoBlank {
|
|
if !decodeAsNil {
|
|
d.swallow()
|
|
}
|
|
} else {
|
|
rv9 = rv.Index(j)
|
|
if d.h.SliceElementReset || decodeAsNil {
|
|
if !rtelem0ZeroValid {
|
|
rtelem0ZeroValid = true
|
|
rtelem0Zero = reflect.Zero(rtelem0)
|
|
}
|
|
rv9.Set(rtelem0Zero)
|
|
}
|
|
if decodeAsNil {
|
|
continue
|
|
}
|
|
|
|
if fn == nil {
|
|
fn = d.cf.get(rtelem, true, true)
|
|
}
|
|
d.decodeValue(rv9, fn, true)
|
|
}
|
|
}
|
|
}
|
|
if f.seq == seqTypeSlice {
|
|
if j < rvlen {
|
|
if rv.CanSet() {
|
|
rv.SetLen(j)
|
|
} else if rvCanset {
|
|
rv = rv.Slice(0, j)
|
|
rvChanged = true
|
|
} // else { d.errorf("kSlice: cannot change non-settable slice") }
|
|
rvlen = j
|
|
} else if j == 0 && rv.IsNil() {
|
|
if rvCanset {
|
|
rv = reflect.MakeSlice(ti.rt, 0, 0)
|
|
rvChanged = true
|
|
} // else { d.errorf("kSlice: cannot change non-settable slice") }
|
|
}
|
|
}
|
|
slh.End()
|
|
|
|
if rvChanged { // infers rvCanset=true, so it can be reset
|
|
rv0.Set(rv)
|
|
}
|
|
}
|
|
|
|
// func (d *Decoder) kArray(f *codecFnInfo, rv reflect.Value) {
|
|
// // d.decodeValueFn(rv.Slice(0, rv.Len()))
|
|
// f.kSlice(rv.Slice(0, rv.Len()))
|
|
// }
|
|
|
|
func (d *Decoder) kMap(f *codecFnInfo, rv reflect.Value) {
|
|
dd := d.d
|
|
containerLen := dd.ReadMapStart()
|
|
elemsep := d.esep
|
|
ti := f.ti
|
|
if rv.IsNil() {
|
|
rv.Set(makeMapReflect(ti.rt, containerLen))
|
|
}
|
|
|
|
if containerLen == 0 {
|
|
dd.ReadMapEnd()
|
|
return
|
|
}
|
|
|
|
ktype, vtype := ti.key, ti.elem
|
|
ktypeId := rt2id(ktype)
|
|
vtypeKind := vtype.Kind()
|
|
|
|
var keyFn, valFn *codecFn
|
|
var ktypeLo, vtypeLo reflect.Type
|
|
|
|
for ktypeLo = ktype; ktypeLo.Kind() == reflect.Ptr; ktypeLo = ktypeLo.Elem() {
|
|
}
|
|
|
|
for vtypeLo = vtype; vtypeLo.Kind() == reflect.Ptr; vtypeLo = vtypeLo.Elem() {
|
|
}
|
|
|
|
var mapGet, mapSet bool
|
|
rvvImmut := isImmutableKind(vtypeKind)
|
|
if !d.h.MapValueReset {
|
|
// if pointer, mapGet = true
|
|
// if interface, mapGet = true if !DecodeNakedAlways (else false)
|
|
// if builtin, mapGet = false
|
|
// else mapGet = true
|
|
if vtypeKind == reflect.Ptr {
|
|
mapGet = true
|
|
} else if vtypeKind == reflect.Interface {
|
|
if !d.h.InterfaceReset {
|
|
mapGet = true
|
|
}
|
|
} else if !rvvImmut {
|
|
mapGet = true
|
|
}
|
|
}
|
|
|
|
var rvk, rvkp, rvv, rvz reflect.Value
|
|
rvkMut := !isImmutableKind(ktype.Kind()) // if ktype is immutable, then re-use the same rvk.
|
|
ktypeIsString := ktypeId == stringTypId
|
|
ktypeIsIntf := ktypeId == intfTypId
|
|
hasLen := containerLen > 0
|
|
var kstrbs []byte
|
|
d.cfer()
|
|
for j := 0; (hasLen && j < containerLen) || !(hasLen || dd.CheckBreak()); j++ {
|
|
if rvkMut || !rvkp.IsValid() {
|
|
rvkp = reflect.New(ktype)
|
|
rvk = rvkp.Elem()
|
|
}
|
|
if elemsep {
|
|
dd.ReadMapElemKey()
|
|
}
|
|
if false && dd.TryDecodeAsNil() { // nil cannot be a map key, so disregard this block
|
|
// Previously, if a nil key, we just ignored the mapped value and continued.
|
|
// However, that makes the result of encoding and then decoding map[intf]intf{nil:nil}
|
|
// to be an empty map.
|
|
// Instead, we treat a nil key as the zero value of the type.
|
|
rvk.Set(reflect.Zero(ktype))
|
|
} else if ktypeIsString {
|
|
kstrbs = dd.DecodeStringAsBytes()
|
|
rvk.SetString(stringView(kstrbs))
|
|
// NOTE: if doing an insert, you MUST use a real string (not stringview)
|
|
} else {
|
|
if keyFn == nil {
|
|
keyFn = d.cf.get(ktypeLo, true, true)
|
|
}
|
|
d.decodeValue(rvk, keyFn, true)
|
|
}
|
|
// special case if a byte array.
|
|
if ktypeIsIntf {
|
|
if rvk2 := rvk.Elem(); rvk2.IsValid() {
|
|
if rvk2.Type() == uint8SliceTyp {
|
|
rvk = reflect.ValueOf(d.string(rvk2.Bytes()))
|
|
} else {
|
|
rvk = rvk2
|
|
}
|
|
}
|
|
}
|
|
|
|
if elemsep {
|
|
dd.ReadMapElemValue()
|
|
}
|
|
|
|
// Brittle, but OK per TryDecodeAsNil() contract.
|
|
// i.e. TryDecodeAsNil never shares slices with other decDriver procedures
|
|
if dd.TryDecodeAsNil() {
|
|
if ktypeIsString {
|
|
rvk.SetString(d.string(kstrbs))
|
|
}
|
|
if d.h.DeleteOnNilMapValue {
|
|
rv.SetMapIndex(rvk, reflect.Value{})
|
|
} else {
|
|
rv.SetMapIndex(rvk, reflect.Zero(vtype))
|
|
}
|
|
continue
|
|
}
|
|
|
|
mapSet = true // set to false if u do a get, and its a non-nil pointer
|
|
if mapGet {
|
|
// mapGet true only in case where kind=Ptr|Interface or kind is otherwise mutable.
|
|
rvv = rv.MapIndex(rvk)
|
|
if !rvv.IsValid() {
|
|
rvv = reflect.New(vtype).Elem()
|
|
} else if vtypeKind == reflect.Ptr {
|
|
if rvv.IsNil() {
|
|
rvv = reflect.New(vtype).Elem()
|
|
} else {
|
|
mapSet = false
|
|
}
|
|
} else if vtypeKind == reflect.Interface {
|
|
// not addressable, and thus not settable.
|
|
// e MUST create a settable/addressable variant
|
|
rvv2 := reflect.New(rvv.Type()).Elem()
|
|
if !rvv.IsNil() {
|
|
rvv2.Set(rvv)
|
|
}
|
|
rvv = rvv2
|
|
}
|
|
// else it is ~mutable, and we can just decode into it directly
|
|
} else if rvvImmut {
|
|
if !rvz.IsValid() {
|
|
rvz = reflect.New(vtype).Elem()
|
|
}
|
|
rvv = rvz
|
|
} else {
|
|
rvv = reflect.New(vtype).Elem()
|
|
}
|
|
|
|
// We MUST be done with the stringview of the key, before decoding the value
|
|
// so that we don't bastardize the reused byte array.
|
|
if mapSet && ktypeIsString {
|
|
rvk.SetString(d.string(kstrbs))
|
|
}
|
|
if valFn == nil {
|
|
valFn = d.cf.get(vtypeLo, true, true)
|
|
}
|
|
d.decodeValue(rvv, valFn, true)
|
|
// d.decodeValueFn(rvv, valFn)
|
|
if mapSet {
|
|
rv.SetMapIndex(rvk, rvv)
|
|
}
|
|
// if ktypeIsString {
|
|
// // keepAlive4StringView(kstrbs) // not needed, as reference is outside loop
|
|
// }
|
|
}
|
|
|
|
dd.ReadMapEnd()
|
|
}
|
|
|
|
// decNaked is used to keep track of the primitives decoded.
|
|
// Without it, we would have to decode each primitive and wrap it
|
|
// in an interface{}, causing an allocation.
|
|
// In this model, the primitives are decoded in a "pseudo-atomic" fashion,
|
|
// so we can rest assured that no other decoding happens while these
|
|
// primitives are being decoded.
|
|
//
|
|
// maps and arrays are not handled by this mechanism.
|
|
// However, RawExt is, and we accommodate for extensions that decode
|
|
// RawExt from DecodeNaked, but need to decode the value subsequently.
|
|
// kInterfaceNaked and swallow, which call DecodeNaked, handle this caveat.
|
|
//
|
|
// However, decNaked also keeps some arrays of default maps and slices
|
|
// used in DecodeNaked. This way, we can get a pointer to it
|
|
// without causing a new heap allocation.
|
|
//
|
|
// kInterfaceNaked will ensure that there is no allocation for the common
|
|
// uses.
|
|
|
|
type decNakedContainers struct {
|
|
// array/stacks for reducing allocation
|
|
// keep arrays at the bottom? Chance is that they are not used much.
|
|
ia [arrayCacheLen]interface{}
|
|
ma [arrayCacheLen]map[interface{}]interface{}
|
|
na [arrayCacheLen]map[string]interface{}
|
|
sa [arrayCacheLen][]interface{}
|
|
|
|
// ria [arrayCacheLen]reflect.Value // not needed, as we decode directly into &ia[n]
|
|
rma, rna, rsa [arrayCacheLen]reflect.Value // reflect.Value mapping to above
|
|
}
|
|
|
|
func (n *decNakedContainers) init() {
|
|
for i := 0; i < arrayCacheLen; i++ {
|
|
// n.ria[i] = reflect.ValueOf(&(n.ia[i])).Elem()
|
|
n.rma[i] = reflect.ValueOf(&(n.ma[i])).Elem()
|
|
n.rna[i] = reflect.ValueOf(&(n.na[i])).Elem()
|
|
n.rsa[i] = reflect.ValueOf(&(n.sa[i])).Elem()
|
|
}
|
|
}
|
|
|
|
type decNaked struct {
|
|
// r RawExt // used for RawExt, uint, []byte.
|
|
|
|
// primitives below
|
|
u uint64
|
|
i int64
|
|
f float64
|
|
l []byte
|
|
s string
|
|
|
|
// ---- cpu cache line boundary?
|
|
t time.Time
|
|
b bool
|
|
|
|
// state
|
|
v valueType
|
|
li, lm, ln, ls int8
|
|
inited bool
|
|
|
|
*decNakedContainers
|
|
|
|
ru, ri, rf, rl, rs, rb, rt reflect.Value // mapping to the primitives above
|
|
|
|
// _ [6]uint64 // padding // no padding - rt goes into next cache line
|
|
}
|
|
|
|
func (n *decNaked) init() {
|
|
if n.inited {
|
|
return
|
|
}
|
|
n.ru = reflect.ValueOf(&n.u).Elem()
|
|
n.ri = reflect.ValueOf(&n.i).Elem()
|
|
n.rf = reflect.ValueOf(&n.f).Elem()
|
|
n.rl = reflect.ValueOf(&n.l).Elem()
|
|
n.rs = reflect.ValueOf(&n.s).Elem()
|
|
n.rt = reflect.ValueOf(&n.t).Elem()
|
|
n.rb = reflect.ValueOf(&n.b).Elem()
|
|
|
|
n.inited = true
|
|
// n.rr[] = reflect.ValueOf(&n.)
|
|
}
|
|
|
|
func (n *decNaked) initContainers() {
|
|
if n.decNakedContainers == nil {
|
|
n.decNakedContainers = new(decNakedContainers)
|
|
n.decNakedContainers.init()
|
|
}
|
|
}
|
|
|
|
func (n *decNaked) reset() {
|
|
if n == nil {
|
|
return
|
|
}
|
|
n.li, n.lm, n.ln, n.ls = 0, 0, 0, 0
|
|
}
|
|
|
|
type rtid2rv struct {
|
|
rtid uintptr
|
|
rv reflect.Value
|
|
}
|
|
|
|
// --------------
|
|
|
|
type decReaderSwitch struct {
|
|
rb bytesDecReader
|
|
// ---- cpu cache line boundary?
|
|
ri *ioDecReader
|
|
mtr, str bool // whether maptype or slicetype are known types
|
|
|
|
be bool // is binary encoding
|
|
bytes bool // is bytes reader
|
|
js bool // is json handle
|
|
jsms bool // is json handle, and MapKeyAsString
|
|
esep bool // has elem separators
|
|
}
|
|
|
|
// TODO: Uncomment after mid-stack inlining enabled in go 1.11
|
|
//
|
|
// func (z *decReaderSwitch) unreadn1() {
|
|
// if z.bytes {
|
|
// z.rb.unreadn1()
|
|
// } else {
|
|
// z.ri.unreadn1()
|
|
// }
|
|
// }
|
|
// func (z *decReaderSwitch) readx(n int) []byte {
|
|
// if z.bytes {
|
|
// return z.rb.readx(n)
|
|
// }
|
|
// return z.ri.readx(n)
|
|
// }
|
|
// func (z *decReaderSwitch) readb(s []byte) {
|
|
// if z.bytes {
|
|
// z.rb.readb(s)
|
|
// } else {
|
|
// z.ri.readb(s)
|
|
// }
|
|
// }
|
|
// func (z *decReaderSwitch) readn1() uint8 {
|
|
// if z.bytes {
|
|
// return z.rb.readn1()
|
|
// }
|
|
// return z.ri.readn1()
|
|
// }
|
|
// func (z *decReaderSwitch) numread() int {
|
|
// if z.bytes {
|
|
// return z.rb.numread()
|
|
// }
|
|
// return z.ri.numread()
|
|
// }
|
|
// func (z *decReaderSwitch) track() {
|
|
// if z.bytes {
|
|
// z.rb.track()
|
|
// } else {
|
|
// z.ri.track()
|
|
// }
|
|
// }
|
|
// func (z *decReaderSwitch) stopTrack() []byte {
|
|
// if z.bytes {
|
|
// return z.rb.stopTrack()
|
|
// }
|
|
// return z.ri.stopTrack()
|
|
// }
|
|
// func (z *decReaderSwitch) skip(accept *bitset256) (token byte) {
|
|
// if z.bytes {
|
|
// return z.rb.skip(accept)
|
|
// }
|
|
// return z.ri.skip(accept)
|
|
// }
|
|
// func (z *decReaderSwitch) readTo(in []byte, accept *bitset256) (out []byte) {
|
|
// if z.bytes {
|
|
// return z.rb.readTo(in, accept)
|
|
// }
|
|
// return z.ri.readTo(in, accept)
|
|
// }
|
|
// func (z *decReaderSwitch) readUntil(in []byte, stop byte) (out []byte) {
|
|
// if z.bytes {
|
|
// return z.rb.readUntil(in, stop)
|
|
// }
|
|
// return z.ri.readUntil(in, stop)
|
|
// }
|
|
|
|
// A Decoder reads and decodes an object from an input stream in the codec format.
|
|
type Decoder struct {
|
|
panicHdl
|
|
// hopefully, reduce derefencing cost by laying the decReader inside the Decoder.
|
|
// Try to put things that go together to fit within a cache line (8 words).
|
|
|
|
d decDriver
|
|
// NOTE: Decoder shouldn't call it's read methods,
|
|
// as the handler MAY need to do some coordination.
|
|
r decReader
|
|
h *BasicHandle
|
|
bi *bufioDecReader
|
|
// cache the mapTypeId and sliceTypeId for faster comparisons
|
|
mtid uintptr
|
|
stid uintptr
|
|
|
|
// ---- cpu cache line boundary?
|
|
decReaderSwitch
|
|
|
|
// ---- cpu cache line boundary?
|
|
codecFnPooler
|
|
// cr containerStateRecv
|
|
n *decNaked
|
|
nsp *sync.Pool
|
|
err error
|
|
|
|
// ---- cpu cache line boundary?
|
|
b [decScratchByteArrayLen]byte // scratch buffer, used by Decoder and xxxEncDrivers
|
|
is map[string]string // used for interning strings
|
|
|
|
// padding - false sharing help // modify 232 if Decoder struct changes.
|
|
// _ [cacheLineSize - 232%cacheLineSize]byte
|
|
}
|
|
|
|
// NewDecoder returns a Decoder for decoding a stream of bytes from an io.Reader.
|
|
//
|
|
// For efficiency, Users are encouraged to pass in a memory buffered reader
|
|
// (eg bufio.Reader, bytes.Buffer).
|
|
func NewDecoder(r io.Reader, h Handle) *Decoder {
|
|
d := newDecoder(h)
|
|
d.Reset(r)
|
|
return d
|
|
}
|
|
|
|
// NewDecoderBytes returns a Decoder which efficiently decodes directly
|
|
// from a byte slice with zero copying.
|
|
func NewDecoderBytes(in []byte, h Handle) *Decoder {
|
|
d := newDecoder(h)
|
|
d.ResetBytes(in)
|
|
return d
|
|
}
|
|
|
|
var defaultDecNaked decNaked
|
|
|
|
func newDecoder(h Handle) *Decoder {
|
|
d := &Decoder{h: h.getBasicHandle(), err: errDecoderNotInitialized}
|
|
d.hh = h
|
|
d.be = h.isBinary()
|
|
// NOTE: do not initialize d.n here. It is lazily initialized in d.naked()
|
|
var jh *JsonHandle
|
|
jh, d.js = h.(*JsonHandle)
|
|
if d.js {
|
|
d.jsms = jh.MapKeyAsString
|
|
}
|
|
d.esep = d.hh.hasElemSeparators()
|
|
if d.h.InternString {
|
|
d.is = make(map[string]string, 32)
|
|
}
|
|
d.d = h.newDecDriver(d)
|
|
// d.cr, _ = d.d.(containerStateRecv)
|
|
return d
|
|
}
|
|
|
|
func (d *Decoder) resetCommon() {
|
|
d.n.reset()
|
|
d.d.reset()
|
|
d.err = nil
|
|
// reset all things which were cached from the Handle, but could change
|
|
d.mtid, d.stid = 0, 0
|
|
d.mtr, d.str = false, false
|
|
if d.h.MapType != nil {
|
|
d.mtid = rt2id(d.h.MapType)
|
|
d.mtr = fastpathAV.index(d.mtid) != -1
|
|
}
|
|
if d.h.SliceType != nil {
|
|
d.stid = rt2id(d.h.SliceType)
|
|
d.str = fastpathAV.index(d.stid) != -1
|
|
}
|
|
}
|
|
|
|
// Reset the Decoder with a new Reader to decode from,
|
|
// clearing all state from last run(s).
|
|
func (d *Decoder) Reset(r io.Reader) {
|
|
if r == nil {
|
|
return
|
|
}
|
|
if d.bi == nil {
|
|
d.bi = new(bufioDecReader)
|
|
}
|
|
d.bytes = false
|
|
if d.h.ReaderBufferSize > 0 {
|
|
d.bi.buf = make([]byte, 0, d.h.ReaderBufferSize)
|
|
d.bi.reset(r)
|
|
d.r = d.bi
|
|
} else {
|
|
// d.ri.x = &d.b
|
|
// d.s = d.sa[:0]
|
|
if d.ri == nil {
|
|
d.ri = new(ioDecReader)
|
|
}
|
|
d.ri.reset(r)
|
|
d.r = d.ri
|
|
}
|
|
d.resetCommon()
|
|
}
|
|
|
|
// ResetBytes resets the Decoder with a new []byte to decode from,
|
|
// clearing all state from last run(s).
|
|
func (d *Decoder) ResetBytes(in []byte) {
|
|
if in == nil {
|
|
return
|
|
}
|
|
d.bytes = true
|
|
d.rb.reset(in)
|
|
d.r = &d.rb
|
|
d.resetCommon()
|
|
}
|
|
|
|
// naked must be called before each call to .DecodeNaked,
|
|
// as they will use it.
|
|
func (d *Decoder) naked() *decNaked {
|
|
if d.n == nil {
|
|
// consider one of:
|
|
// - get from sync.Pool (if GC is frequent, there's no value here)
|
|
// - new alloc (safest. only init'ed if it a naked decode will be done)
|
|
// - field in Decoder (makes the Decoder struct very big)
|
|
// To support using a decoder where a DecodeNaked is not needed,
|
|
// we prefer #1 or #2.
|
|
// d.n = new(decNaked) // &d.nv // new(decNaked) // grab from a sync.Pool
|
|
// d.n.init()
|
|
var v interface{}
|
|
d.nsp, v = pool.decNaked()
|
|
d.n = v.(*decNaked)
|
|
}
|
|
return d.n
|
|
}
|
|
|
|
// Decode decodes the stream from reader and stores the result in the
|
|
// value pointed to by v. v cannot be a nil pointer. v can also be
|
|
// a reflect.Value of a pointer.
|
|
//
|
|
// Note that a pointer to a nil interface is not a nil pointer.
|
|
// If you do not know what type of stream it is, pass in a pointer to a nil interface.
|
|
// We will decode and store a value in that nil interface.
|
|
//
|
|
// Sample usages:
|
|
// // Decoding into a non-nil typed value
|
|
// var f float32
|
|
// err = codec.NewDecoder(r, handle).Decode(&f)
|
|
//
|
|
// // Decoding into nil interface
|
|
// var v interface{}
|
|
// dec := codec.NewDecoder(r, handle)
|
|
// err = dec.Decode(&v)
|
|
//
|
|
// When decoding into a nil interface{}, we will decode into an appropriate value based
|
|
// on the contents of the stream:
|
|
// - Numbers are decoded as float64, int64 or uint64.
|
|
// - Other values are decoded appropriately depending on the type:
|
|
// bool, string, []byte, time.Time, etc
|
|
// - Extensions are decoded as RawExt (if no ext function registered for the tag)
|
|
// Configurations exist on the Handle to override defaults
|
|
// (e.g. for MapType, SliceType and how to decode raw bytes).
|
|
//
|
|
// When decoding into a non-nil interface{} value, the mode of encoding is based on the
|
|
// type of the value. When a value is seen:
|
|
// - If an extension is registered for it, call that extension function
|
|
// - If it implements BinaryUnmarshaler, call its UnmarshalBinary(data []byte) error
|
|
// - Else decode it based on its reflect.Kind
|
|
//
|
|
// There are some special rules when decoding into containers (slice/array/map/struct).
|
|
// Decode will typically use the stream contents to UPDATE the container.
|
|
// - A map can be decoded from a stream map, by updating matching keys.
|
|
// - A slice can be decoded from a stream array,
|
|
// by updating the first n elements, where n is length of the stream.
|
|
// - A slice can be decoded from a stream map, by decoding as if
|
|
// it contains a sequence of key-value pairs.
|
|
// - A struct can be decoded from a stream map, by updating matching fields.
|
|
// - A struct can be decoded from a stream array,
|
|
// by updating fields as they occur in the struct (by index).
|
|
//
|
|
// When decoding a stream map or array with length of 0 into a nil map or slice,
|
|
// we reset the destination map or slice to a zero-length value.
|
|
//
|
|
// However, when decoding a stream nil, we reset the destination container
|
|
// to its "zero" value (e.g. nil for slice/map, etc).
|
|
//
|
|
// Note: we allow nil values in the stream anywhere except for map keys.
|
|
// A nil value in the encoded stream where a map key is expected is treated as an error.
|
|
func (d *Decoder) Decode(v interface{}) (err error) {
|
|
defer d.deferred(&err)
|
|
d.MustDecode(v)
|
|
return
|
|
}
|
|
|
|
// MustDecode is like Decode, but panics if unable to Decode.
|
|
// This provides insight to the code location that triggered the error.
|
|
func (d *Decoder) MustDecode(v interface{}) {
|
|
// TODO: Top-level: ensure that v is a pointer and not nil.
|
|
if d.err != nil {
|
|
panic(d.err)
|
|
}
|
|
if d.d.TryDecodeAsNil() {
|
|
setZero(v)
|
|
} else {
|
|
d.decode(v)
|
|
}
|
|
d.alwaysAtEnd()
|
|
// xprintf(">>>>>>>> >>>>>>>> num decFns: %v\n", d.cf.sn)
|
|
}
|
|
|
|
func (d *Decoder) deferred(err1 *error) {
|
|
d.alwaysAtEnd()
|
|
if recoverPanicToErr {
|
|
if x := recover(); x != nil {
|
|
panicValToErr(d, x, err1)
|
|
panicValToErr(d, x, &d.err)
|
|
}
|
|
}
|
|
}
|
|
|
|
func (d *Decoder) alwaysAtEnd() {
|
|
if d.n != nil {
|
|
// if n != nil, then nsp != nil (they are always set together)
|
|
d.nsp.Put(d.n)
|
|
d.n, d.nsp = nil, nil
|
|
}
|
|
d.codecFnPooler.alwaysAtEnd()
|
|
}
|
|
|
|
// // this is not a smart swallow, as it allocates objects and does unnecessary work.
|
|
// func (d *Decoder) swallowViaHammer() {
|
|
// var blank interface{}
|
|
// d.decodeValueNoFn(reflect.ValueOf(&blank).Elem())
|
|
// }
|
|
|
|
func (d *Decoder) swallow() {
|
|
// smarter decode that just swallows the content
|
|
dd := d.d
|
|
if dd.TryDecodeAsNil() {
|
|
return
|
|
}
|
|
elemsep := d.esep
|
|
switch dd.ContainerType() {
|
|
case valueTypeMap:
|
|
containerLen := dd.ReadMapStart()
|
|
hasLen := containerLen >= 0
|
|
for j := 0; (hasLen && j < containerLen) || !(hasLen || dd.CheckBreak()); j++ {
|
|
// if clenGtEqualZero {if j >= containerLen {break} } else if dd.CheckBreak() {break}
|
|
if elemsep {
|
|
dd.ReadMapElemKey()
|
|
}
|
|
d.swallow()
|
|
if elemsep {
|
|
dd.ReadMapElemValue()
|
|
}
|
|
d.swallow()
|
|
}
|
|
dd.ReadMapEnd()
|
|
case valueTypeArray:
|
|
containerLen := dd.ReadArrayStart()
|
|
hasLen := containerLen >= 0
|
|
for j := 0; (hasLen && j < containerLen) || !(hasLen || dd.CheckBreak()); j++ {
|
|
if elemsep {
|
|
dd.ReadArrayElem()
|
|
}
|
|
d.swallow()
|
|
}
|
|
dd.ReadArrayEnd()
|
|
case valueTypeBytes:
|
|
dd.DecodeBytes(d.b[:], true)
|
|
case valueTypeString:
|
|
dd.DecodeStringAsBytes()
|
|
default:
|
|
// these are all primitives, which we can get from decodeNaked
|
|
// if RawExt using Value, complete the processing.
|
|
n := d.naked()
|
|
dd.DecodeNaked()
|
|
if n.v == valueTypeExt && n.l == nil {
|
|
n.initContainers()
|
|
if n.li < arrayCacheLen {
|
|
n.ia[n.li] = nil
|
|
n.li++
|
|
d.decode(&n.ia[n.li-1])
|
|
n.ia[n.li-1] = nil
|
|
n.li--
|
|
} else {
|
|
var v2 interface{}
|
|
d.decode(&v2)
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
func setZero(iv interface{}) {
|
|
if iv == nil || definitelyNil(iv) {
|
|
return
|
|
}
|
|
var canDecode bool
|
|
switch v := iv.(type) {
|
|
case *string:
|
|
*v = ""
|
|
case *bool:
|
|
*v = false
|
|
case *int:
|
|
*v = 0
|
|
case *int8:
|
|
*v = 0
|
|
case *int16:
|
|
*v = 0
|
|
case *int32:
|
|
*v = 0
|
|
case *int64:
|
|
*v = 0
|
|
case *uint:
|
|
*v = 0
|
|
case *uint8:
|
|
*v = 0
|
|
case *uint16:
|
|
*v = 0
|
|
case *uint32:
|
|
*v = 0
|
|
case *uint64:
|
|
*v = 0
|
|
case *float32:
|
|
*v = 0
|
|
case *float64:
|
|
*v = 0
|
|
case *[]uint8:
|
|
*v = nil
|
|
case *Raw:
|
|
*v = nil
|
|
case *time.Time:
|
|
*v = time.Time{}
|
|
case reflect.Value:
|
|
if v, canDecode = isDecodeable(v); canDecode && v.CanSet() {
|
|
v.Set(reflect.Zero(v.Type()))
|
|
} // TODO: else drain if chan, clear if map, set all to nil if slice???
|
|
default:
|
|
if !fastpathDecodeSetZeroTypeSwitch(iv) {
|
|
v := reflect.ValueOf(iv)
|
|
if v, canDecode = isDecodeable(v); canDecode && v.CanSet() {
|
|
v.Set(reflect.Zero(v.Type()))
|
|
} // TODO: else drain if chan, clear if map, set all to nil if slice???
|
|
}
|
|
}
|
|
}
|
|
|
|
func (d *Decoder) decode(iv interface{}) {
|
|
// check nil and interfaces explicitly,
|
|
// so that type switches just have a run of constant non-interface types.
|
|
if iv == nil {
|
|
d.errorstr(errstrCannotDecodeIntoNil)
|
|
return
|
|
}
|
|
if v, ok := iv.(Selfer); ok {
|
|
v.CodecDecodeSelf(d)
|
|
return
|
|
}
|
|
|
|
switch v := iv.(type) {
|
|
// case nil:
|
|
// case Selfer:
|
|
|
|
case reflect.Value:
|
|
v = d.ensureDecodeable(v)
|
|
d.decodeValue(v, nil, true)
|
|
|
|
case *string:
|
|
*v = d.d.DecodeString()
|
|
case *bool:
|
|
*v = d.d.DecodeBool()
|
|
case *int:
|
|
*v = int(chkOvf.IntV(d.d.DecodeInt64(), intBitsize))
|
|
case *int8:
|
|
*v = int8(chkOvf.IntV(d.d.DecodeInt64(), 8))
|
|
case *int16:
|
|
*v = int16(chkOvf.IntV(d.d.DecodeInt64(), 16))
|
|
case *int32:
|
|
*v = int32(chkOvf.IntV(d.d.DecodeInt64(), 32))
|
|
case *int64:
|
|
*v = d.d.DecodeInt64()
|
|
case *uint:
|
|
*v = uint(chkOvf.UintV(d.d.DecodeUint64(), uintBitsize))
|
|
case *uint8:
|
|
*v = uint8(chkOvf.UintV(d.d.DecodeUint64(), 8))
|
|
case *uint16:
|
|
*v = uint16(chkOvf.UintV(d.d.DecodeUint64(), 16))
|
|
case *uint32:
|
|
*v = uint32(chkOvf.UintV(d.d.DecodeUint64(), 32))
|
|
case *uint64:
|
|
*v = d.d.DecodeUint64()
|
|
case *float32:
|
|
f64 := d.d.DecodeFloat64()
|
|
if chkOvf.Float32(f64) {
|
|
d.errorf("float32 overflow: %v", f64)
|
|
}
|
|
*v = float32(f64)
|
|
case *float64:
|
|
*v = d.d.DecodeFloat64()
|
|
case *[]uint8:
|
|
*v = d.d.DecodeBytes(*v, false)
|
|
case []uint8:
|
|
b := d.d.DecodeBytes(v, false)
|
|
if !(len(b) > 0 && len(b) == len(v) && &b[0] == &v[0]) {
|
|
copy(v, b)
|
|
}
|
|
case *time.Time:
|
|
*v = d.d.DecodeTime()
|
|
case *Raw:
|
|
*v = d.rawBytes()
|
|
|
|
case *interface{}:
|
|
d.decodeValue(reflect.ValueOf(iv).Elem(), nil, true)
|
|
// d.decodeValueNotNil(reflect.ValueOf(iv).Elem())
|
|
|
|
default:
|
|
if !fastpathDecodeTypeSwitch(iv, d) {
|
|
v := reflect.ValueOf(iv)
|
|
v = d.ensureDecodeable(v)
|
|
d.decodeValue(v, nil, false)
|
|
// d.decodeValueFallback(v)
|
|
}
|
|
}
|
|
}
|
|
|
|
func (d *Decoder) decodeValue(rv reflect.Value, fn *codecFn, chkAll bool) {
|
|
// If stream is not containing a nil value, then we can deref to the base
|
|
// non-pointer value, and decode into that.
|
|
var rvp reflect.Value
|
|
var rvpValid bool
|
|
if rv.Kind() == reflect.Ptr {
|
|
rvpValid = true
|
|
for {
|
|
if rv.IsNil() {
|
|
rv.Set(reflect.New(rv.Type().Elem()))
|
|
}
|
|
rvp = rv
|
|
rv = rv.Elem()
|
|
if rv.Kind() != reflect.Ptr {
|
|
break
|
|
}
|
|
}
|
|
}
|
|
|
|
if fn == nil {
|
|
// always pass checkCodecSelfer=true, in case T or ****T is passed, where *T is a Selfer
|
|
fn = d.cfer().get(rv.Type(), chkAll, true) // chkAll, chkAll)
|
|
}
|
|
if fn.i.addrD {
|
|
if rvpValid {
|
|
fn.fd(d, &fn.i, rvp)
|
|
} else if rv.CanAddr() {
|
|
fn.fd(d, &fn.i, rv.Addr())
|
|
} else if !fn.i.addrF {
|
|
fn.fd(d, &fn.i, rv)
|
|
} else {
|
|
d.errorf("cannot decode into a non-pointer value")
|
|
}
|
|
} else {
|
|
fn.fd(d, &fn.i, rv)
|
|
}
|
|
// return rv
|
|
}
|
|
|
|
func (d *Decoder) structFieldNotFound(index int, rvkencname string) {
|
|
// NOTE: rvkencname may be a stringView, so don't pass it to another function.
|
|
if d.h.ErrorIfNoField {
|
|
if index >= 0 {
|
|
d.errorf("no matching struct field found when decoding stream array at index %v", index)
|
|
return
|
|
} else if rvkencname != "" {
|
|
d.errorf("no matching struct field found when decoding stream map with key " + rvkencname)
|
|
return
|
|
}
|
|
}
|
|
d.swallow()
|
|
}
|
|
|
|
func (d *Decoder) arrayCannotExpand(sliceLen, streamLen int) {
|
|
if d.h.ErrorIfNoArrayExpand {
|
|
d.errorf("cannot expand array len during decode from %v to %v", sliceLen, streamLen)
|
|
}
|
|
}
|
|
|
|
func isDecodeable(rv reflect.Value) (rv2 reflect.Value, canDecode bool) {
|
|
switch rv.Kind() {
|
|
case reflect.Array:
|
|
return rv, true
|
|
case reflect.Ptr:
|
|
if !rv.IsNil() {
|
|
return rv.Elem(), true
|
|
}
|
|
case reflect.Slice, reflect.Chan, reflect.Map:
|
|
if !rv.IsNil() {
|
|
return rv, true
|
|
}
|
|
}
|
|
return
|
|
}
|
|
|
|
func (d *Decoder) ensureDecodeable(rv reflect.Value) (rv2 reflect.Value) {
|
|
// decode can take any reflect.Value that is a inherently addressable i.e.
|
|
// - array
|
|
// - non-nil chan (we will SEND to it)
|
|
// - non-nil slice (we will set its elements)
|
|
// - non-nil map (we will put into it)
|
|
// - non-nil pointer (we can "update" it)
|
|
rv2, canDecode := isDecodeable(rv)
|
|
if canDecode {
|
|
return
|
|
}
|
|
if !rv.IsValid() {
|
|
d.errorstr(errstrCannotDecodeIntoNil)
|
|
return
|
|
}
|
|
if !rv.CanInterface() {
|
|
d.errorf("cannot decode into a value without an interface: %v", rv)
|
|
return
|
|
}
|
|
rvi := rv2i(rv)
|
|
rvk := rv.Kind()
|
|
d.errorf("cannot decode into value of kind: %v, type: %T, %v", rvk, rvi, rvi)
|
|
return
|
|
}
|
|
|
|
// Possibly get an interned version of a string
|
|
//
|
|
// This should mostly be used for map keys, where the key type is string.
|
|
// This is because keys of a map/struct are typically reused across many objects.
|
|
func (d *Decoder) string(v []byte) (s string) {
|
|
if d.is == nil {
|
|
return string(v) // don't return stringView, as we need a real string here.
|
|
}
|
|
s, ok := d.is[string(v)] // no allocation here, per go implementation
|
|
if !ok {
|
|
s = string(v) // new allocation here
|
|
d.is[s] = s
|
|
}
|
|
return s
|
|
}
|
|
|
|
// nextValueBytes returns the next value in the stream as a set of bytes.
|
|
func (d *Decoder) nextValueBytes() (bs []byte) {
|
|
d.d.uncacheRead()
|
|
d.r.track()
|
|
d.swallow()
|
|
bs = d.r.stopTrack()
|
|
return
|
|
}
|
|
|
|
func (d *Decoder) rawBytes() []byte {
|
|
// ensure that this is not a view into the bytes
|
|
// i.e. make new copy always.
|
|
bs := d.nextValueBytes()
|
|
bs2 := make([]byte, len(bs))
|
|
copy(bs2, bs)
|
|
return bs2
|
|
}
|
|
|
|
func (d *Decoder) wrapErrstr(v interface{}, err *error) {
|
|
*err = fmt.Errorf("%s decode error [pos %d]: %v", d.hh.Name(), d.r.numread(), v)
|
|
}
|
|
|
|
func (d *Decoder) NumBytesRead() int {
|
|
return d.r.numread()
|
|
}
|
|
|
|
// --------------------------------------------------
|
|
|
|
// decSliceHelper assists when decoding into a slice, from a map or an array in the stream.
|
|
// A slice can be set from a map or array in stream. This supports the MapBySlice interface.
|
|
type decSliceHelper struct {
|
|
d *Decoder
|
|
// ct valueType
|
|
array bool
|
|
}
|
|
|
|
func (d *Decoder) decSliceHelperStart() (x decSliceHelper, clen int) {
|
|
dd := d.d
|
|
ctyp := dd.ContainerType()
|
|
switch ctyp {
|
|
case valueTypeArray:
|
|
x.array = true
|
|
clen = dd.ReadArrayStart()
|
|
case valueTypeMap:
|
|
clen = dd.ReadMapStart() * 2
|
|
default:
|
|
d.errorf("only encoded map or array can be decoded into a slice (%d)", ctyp)
|
|
}
|
|
// x.ct = ctyp
|
|
x.d = d
|
|
return
|
|
}
|
|
|
|
func (x decSliceHelper) End() {
|
|
if x.array {
|
|
x.d.d.ReadArrayEnd()
|
|
} else {
|
|
x.d.d.ReadMapEnd()
|
|
}
|
|
}
|
|
|
|
func (x decSliceHelper) ElemContainerState(index int) {
|
|
if x.array {
|
|
x.d.d.ReadArrayElem()
|
|
} else if index%2 == 0 {
|
|
x.d.d.ReadMapElemKey()
|
|
} else {
|
|
x.d.d.ReadMapElemValue()
|
|
}
|
|
}
|
|
|
|
func decByteSlice(r decReader, clen, maxInitLen int, bs []byte) (bsOut []byte) {
|
|
if clen == 0 {
|
|
return zeroByteSlice
|
|
}
|
|
if len(bs) == clen {
|
|
bsOut = bs
|
|
r.readb(bsOut)
|
|
} else if cap(bs) >= clen {
|
|
bsOut = bs[:clen]
|
|
r.readb(bsOut)
|
|
} else {
|
|
// bsOut = make([]byte, clen)
|
|
len2 := decInferLen(clen, maxInitLen, 1)
|
|
bsOut = make([]byte, len2)
|
|
r.readb(bsOut)
|
|
for len2 < clen {
|
|
len3 := decInferLen(clen-len2, maxInitLen, 1)
|
|
bs3 := bsOut
|
|
bsOut = make([]byte, len2+len3)
|
|
copy(bsOut, bs3)
|
|
r.readb(bsOut[len2:])
|
|
len2 += len3
|
|
}
|
|
}
|
|
return
|
|
}
|
|
|
|
func detachZeroCopyBytes(isBytesReader bool, dest []byte, in []byte) (out []byte) {
|
|
if xlen := len(in); xlen > 0 {
|
|
if isBytesReader || xlen <= scratchByteArrayLen {
|
|
if cap(dest) >= xlen {
|
|
out = dest[:xlen]
|
|
} else {
|
|
out = make([]byte, xlen)
|
|
}
|
|
copy(out, in)
|
|
return
|
|
}
|
|
}
|
|
return in
|
|
}
|
|
|
|
// decInferLen will infer a sensible length, given the following:
|
|
// - clen: length wanted.
|
|
// - maxlen: max length to be returned.
|
|
// if <= 0, it is unset, and we infer it based on the unit size
|
|
// - unit: number of bytes for each element of the collection
|
|
func decInferLen(clen, maxlen, unit int) (rvlen int) {
|
|
// handle when maxlen is not set i.e. <= 0
|
|
if clen <= 0 {
|
|
return
|
|
}
|
|
if unit == 0 {
|
|
return clen
|
|
}
|
|
if maxlen <= 0 {
|
|
// no maxlen defined. Use maximum of 256K memory, with a floor of 4K items.
|
|
// maxlen = 256 * 1024 / unit
|
|
// if maxlen < (4 * 1024) {
|
|
// maxlen = 4 * 1024
|
|
// }
|
|
if unit < (256 / 4) {
|
|
maxlen = 256 * 1024 / unit
|
|
} else {
|
|
maxlen = 4 * 1024
|
|
}
|
|
}
|
|
if clen > maxlen {
|
|
rvlen = maxlen
|
|
} else {
|
|
rvlen = clen
|
|
}
|
|
return
|
|
}
|
|
|
|
func expandSliceRV(s reflect.Value, st reflect.Type, canChange bool, stElemSize, num, slen, scap int) (
|
|
s2 reflect.Value, scap2 int, changed bool, err string) {
|
|
l1 := slen + num // new slice length
|
|
if l1 < slen {
|
|
err = errmsgExpandSliceOverflow
|
|
return
|
|
}
|
|
if l1 <= scap {
|
|
if s.CanSet() {
|
|
s.SetLen(l1)
|
|
} else if canChange {
|
|
s2 = s.Slice(0, l1)
|
|
scap2 = scap
|
|
changed = true
|
|
} else {
|
|
err = errmsgExpandSliceCannotChange
|
|
return
|
|
}
|
|
return
|
|
}
|
|
if !canChange {
|
|
err = errmsgExpandSliceCannotChange
|
|
return
|
|
}
|
|
scap2 = growCap(scap, stElemSize, num)
|
|
s2 = reflect.MakeSlice(st, l1, scap2)
|
|
changed = true
|
|
reflect.Copy(s2, s)
|
|
return
|
|
}
|
|
|
|
func decReadFull(r io.Reader, bs []byte) (n int, err error) {
|
|
var nn int
|
|
for n < len(bs) && err == nil {
|
|
nn, err = r.Read(bs[n:])
|
|
if nn > 0 {
|
|
if err == io.EOF {
|
|
// leave EOF for next time
|
|
err = nil
|
|
}
|
|
n += nn
|
|
}
|
|
}
|
|
|
|
// do not do this - it serves no purpose
|
|
// if n != len(bs) && err == io.EOF { err = io.ErrUnexpectedEOF }
|
|
return
|
|
}
|