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package cbor
import (
"encoding/binary"
"math"
)
func (i Uint) len() int {
return itoarglen(uint64(i))
}
func (i Uint) encode(p []byte) int {
return encodeArg(majorTypeUint, uint64(i), p)
}
func (i NegInt) len() int {
return itoarglen(uint64(i) - 1)
}
func (i NegInt) encode(p []byte) int {
return encodeArg(majorTypeNegInt, uint64(i-1), p)
}
func (s Slice) len() int {
return itoarglen(len(s)) + len(s)
}
func (s Slice) encode(p []byte) int {
off := encodeArg(majorTypeSlice, len(s), p)
copy(p[off:], []byte(s))
return off + len(s)
}
func (s String) len() int {
return itoarglen(len(s)) + len(s)
}
func (s String) encode(p []byte) int {
off := encodeArg(majorTypeString, len(s), p)
copy(p[off:], []byte(s))
return off + len(s)
}
func (l List) len() int {
total := itoarglen(len(l))
for _, v := range l {
total += v.len()
}
return total
}
func (l List) encode(p []byte) int {
off := encodeArg(majorTypeList, len(l), p)
for _, v := range l {
off += v.encode(p[off:])
}
return off
}
func (m Map) len() int {
total := itoarglen(len(m))
for k, v := range m {
total += String(k).len() + v.len()
}
return total
}
func (m Map) encode(p []byte) int {
off := encodeArg(majorTypeMap, len(m), p)
for k, v := range m {
off += String(k).encode(p[off:])
off += v.encode(p[off:])
}
return off
}
func (t Tag) len() int {
return itoarglen(t.ID) + t.Value.len()
}
func (t Tag) encode(p []byte) int {
off := encodeArg(majorTypeTag, t.ID, p)
return off + t.Value.encode(p[off:])
}
func (b Bool) len() int {
return 1
}
func (b Bool) encode(p []byte) int {
if b {
p[0] = compose(majorType7, major7True)
} else {
p[0] = compose(majorType7, major7False)
}
return 1
}
func (*Nil) len() int {
return 1
}
func (*Nil) encode(p []byte) int {
p[0] = compose(majorType7, major7Nil)
return 1
}
func (*Undefined) len() int {
return 1
}
func (*Undefined) encode(p []byte) int {
p[0] = compose(majorType7, major7Undefined)
return 1
}
func (f Float32) len() int {
return 5
}
func (f Float32) encode(p []byte) int {
p[0] = compose(majorType7, major7Float32)
binary.BigEndian.PutUint32(p[1:], math.Float32bits(float32(f)))
return 5
}
func (f Float64) len() int {
return 9
}
func (f Float64) encode(p []byte) int {
p[0] = compose(majorType7, major7Float64)
binary.BigEndian.PutUint64(p[1:], math.Float64bits(float64(f)))
return 9
}
func compose(major majorType, minor byte) byte {
return byte(major)<<5 | minor
}
func itoarglen[I int | uint64](v I) int {
vv := uint64(v)
if vv < 24 {
return 1 // type and len in single byte
} else if vv < 0x100 {
return 2 // type + 1-byte len
} else if vv < 0x10000 {
return 3 // type + 2-byte len
} else if vv < 0x100000000 {
return 5 // type + 4-byte len
}
return 9 // type + 8-byte len
}
func encodeArg[I int | uint64](t majorType, arg I, p []byte) int {
aarg := uint64(arg)
if aarg < 24 {
p[0] = byte(t)<<5 | byte(aarg)
return 1
} else if aarg < 0x100 {
p[0] = compose(t, minorArg1)
p[1] = byte(aarg)
return 2
} else if aarg < 0x10000 {
p[0] = compose(t, minorArg2)
binary.BigEndian.PutUint16(p[1:], uint16(aarg))
return 3
} else if aarg < 0x100000000 {
p[0] = compose(t, minorArg4)
binary.BigEndian.PutUint32(p[1:], uint32(aarg))
return 5
}
p[0] = compose(t, minorArg8)
binary.BigEndian.PutUint64(p[1:], uint64(aarg))
return 9
}
// EncodeRaw encodes opaque CBOR data.
//
// This is used by the encoder for the purpose of embedding document shapes.
// Decode will never return values of this type.
type EncodeRaw []byte
func (v EncodeRaw) len() int { return len(v) }
func (v EncodeRaw) encode(p []byte) int {
copy(p, v)
return len(v)
}
// FixedUint encodes fixed-width Uint values.
//
// This is used by the encoder for the purpose of embedding integrals in
// document shapes. Decode will never return values of this type.
type EncodeFixedUint uint64
func (EncodeFixedUint) len() int { return 9 }
func (v EncodeFixedUint) encode(p []byte) int {
p[0] = compose(majorTypeUint, minorArg8)
binary.BigEndian.PutUint64(p[1:], uint64(v))
return 9
}
// FixedUint encodes fixed-width NegInt values.
//
// This is used by the encoder for the purpose of embedding integrals in
// document shapes. Decode will never return values of this type.
type EncodeFixedNegInt uint64
func (EncodeFixedNegInt) len() int { return 9 }
func (v EncodeFixedNegInt) encode(p []byte) int {
p[0] = compose(majorTypeNegInt, minorArg8)
binary.BigEndian.PutUint64(p[1:], uint64(v-1))
return 9
}
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