gitea/vendor/github.com/tinylib/msgp/msgp/number.go

268 lines
5.4 KiB
Go

package msgp
import (
"math"
"strconv"
)
// The portable parts of the Number implementation
// Number can be
// an int64, uint64, float32,
// or float64 internally.
// It can decode itself
// from any of the native
// messagepack number types.
// The zero-value of Number
// is Int(0). Using the equality
// operator with Number compares
// both the type and the value
// of the number.
type Number struct {
// internally, this
// is just a tagged union.
// the raw bits of the number
// are stored the same way regardless.
bits uint64
typ Type
}
// AsInt sets the number to an int64.
func (n *Number) AsInt(i int64) {
// we always store int(0)
// as {0, InvalidType} in
// order to preserve
// the behavior of the == operator
if i == 0 {
n.typ = InvalidType
n.bits = 0
return
}
n.typ = IntType
n.bits = uint64(i)
}
// AsUint sets the number to a uint64.
func (n *Number) AsUint(u uint64) {
n.typ = UintType
n.bits = u
}
// AsFloat32 sets the value of the number
// to a float32.
func (n *Number) AsFloat32(f float32) {
n.typ = Float32Type
n.bits = uint64(math.Float32bits(f))
}
// AsFloat64 sets the value of the
// number to a float64.
func (n *Number) AsFloat64(f float64) {
n.typ = Float64Type
n.bits = math.Float64bits(f)
}
// Int casts the number as an int64, and
// returns whether or not that was the
// underlying type.
func (n *Number) Int() (int64, bool) {
return int64(n.bits), n.typ == IntType || n.typ == InvalidType
}
// Uint casts the number as a uint64, and returns
// whether or not that was the underlying type.
func (n *Number) Uint() (uint64, bool) {
return n.bits, n.typ == UintType
}
// Float casts the number to a float64, and
// returns whether or not that was the underlying
// type (either a float64 or a float32).
func (n *Number) Float() (float64, bool) {
switch n.typ {
case Float32Type:
return float64(math.Float32frombits(uint32(n.bits))), true
case Float64Type:
return math.Float64frombits(n.bits), true
default:
return 0.0, false
}
}
// Type will return one of:
// Float64Type, Float32Type, UintType, or IntType.
func (n *Number) Type() Type {
if n.typ == InvalidType {
return IntType
}
return n.typ
}
// DecodeMsg implements msgp.Decodable
func (n *Number) DecodeMsg(r *Reader) error {
typ, err := r.NextType()
if err != nil {
return err
}
switch typ {
case Float32Type:
f, err := r.ReadFloat32()
if err != nil {
return err
}
n.AsFloat32(f)
return nil
case Float64Type:
f, err := r.ReadFloat64()
if err != nil {
return err
}
n.AsFloat64(f)
return nil
case IntType:
i, err := r.ReadInt64()
if err != nil {
return err
}
n.AsInt(i)
return nil
case UintType:
u, err := r.ReadUint64()
if err != nil {
return err
}
n.AsUint(u)
return nil
default:
return TypeError{Encoded: typ, Method: IntType}
}
}
// UnmarshalMsg implements msgp.Unmarshaler
func (n *Number) UnmarshalMsg(b []byte) ([]byte, error) {
typ := NextType(b)
switch typ {
case IntType:
i, o, err := ReadInt64Bytes(b)
if err != nil {
return b, err
}
n.AsInt(i)
return o, nil
case UintType:
u, o, err := ReadUint64Bytes(b)
if err != nil {
return b, err
}
n.AsUint(u)
return o, nil
case Float64Type:
f, o, err := ReadFloat64Bytes(b)
if err != nil {
return b, err
}
n.AsFloat64(f)
return o, nil
case Float32Type:
f, o, err := ReadFloat32Bytes(b)
if err != nil {
return b, err
}
n.AsFloat32(f)
return o, nil
default:
return b, TypeError{Method: IntType, Encoded: typ}
}
}
// MarshalMsg implements msgp.Marshaler
func (n *Number) MarshalMsg(b []byte) ([]byte, error) {
switch n.typ {
case IntType:
return AppendInt64(b, int64(n.bits)), nil
case UintType:
return AppendUint64(b, uint64(n.bits)), nil
case Float64Type:
return AppendFloat64(b, math.Float64frombits(n.bits)), nil
case Float32Type:
return AppendFloat32(b, math.Float32frombits(uint32(n.bits))), nil
default:
return AppendInt64(b, 0), nil
}
}
// EncodeMsg implements msgp.Encodable
func (n *Number) EncodeMsg(w *Writer) error {
switch n.typ {
case IntType:
return w.WriteInt64(int64(n.bits))
case UintType:
return w.WriteUint64(n.bits)
case Float64Type:
return w.WriteFloat64(math.Float64frombits(n.bits))
case Float32Type:
return w.WriteFloat32(math.Float32frombits(uint32(n.bits)))
default:
return w.WriteInt64(0)
}
}
// Msgsize implements msgp.Sizer
func (n *Number) Msgsize() int {
switch n.typ {
case Float32Type:
return Float32Size
case Float64Type:
return Float64Size
case IntType:
return Int64Size
case UintType:
return Uint64Size
default:
return 1 // fixint(0)
}
}
// MarshalJSON implements json.Marshaler
func (n *Number) MarshalJSON() ([]byte, error) {
t := n.Type()
if t == InvalidType {
return []byte{'0'}, nil
}
out := make([]byte, 0, 32)
switch t {
case Float32Type, Float64Type:
f, _ := n.Float()
return strconv.AppendFloat(out, f, 'f', -1, 64), nil
case IntType:
i, _ := n.Int()
return strconv.AppendInt(out, i, 10), nil
case UintType:
u, _ := n.Uint()
return strconv.AppendUint(out, u, 10), nil
default:
panic("(*Number).typ is invalid")
}
}
// String implements fmt.Stringer
func (n *Number) String() string {
switch n.typ {
case InvalidType:
return "0"
case Float32Type, Float64Type:
f, _ := n.Float()
return strconv.FormatFloat(f, 'f', -1, 64)
case IntType:
i, _ := n.Int()
return strconv.FormatInt(i, 10)
case UintType:
u, _ := n.Uint()
return strconv.FormatUint(u, 10)
default:
panic("(*Number).typ is invalid")
}
}