lotus/chain/types/bigint.go

85 lines
1.5 KiB
Go

package types
import (
"encoding/json"
"fmt"
"math/big"
cbor "github.com/ipfs/go-ipld-cbor"
"github.com/polydawn/refmt/obj/atlas"
)
func init() {
cbor.RegisterCborType(atlas.BuildEntry(BigInt{}).UseTag(2).Transform().
TransformMarshal(atlas.MakeMarshalTransformFunc(
func(i BigInt) ([]byte, error) {
if i.Int == nil {
return []byte{}, nil
}
return i.Bytes(), nil
})).
TransformUnmarshal(atlas.MakeUnmarshalTransformFunc(
func(x []byte) (BigInt, error) {
return BigFromBytes(x), nil
})).
Complete())
}
var EmptyInt = BigInt{}
type BigInt struct {
*big.Int
}
func NewInt(i uint64) BigInt {
return BigInt{big.NewInt(0).SetUint64(i)}
}
func BigFromBytes(b []byte) BigInt {
i := big.NewInt(0).SetBytes(b)
return BigInt{i}
}
func BigMul(a, b BigInt) BigInt {
return BigInt{big.NewInt(0).Mul(a.Int, b.Int)}
}
func BigAdd(a, b BigInt) BigInt {
return BigInt{big.NewInt(0).Add(a.Int, b.Int)}
}
func BigSub(a, b BigInt) BigInt {
return BigInt{big.NewInt(0).Sub(a.Int, b.Int)}
}
func BigCmp(a, b BigInt) int {
return a.Int.Cmp(b.Int)
}
func (bi *BigInt) Nil() bool {
return bi.Int == nil
}
func (bi *BigInt) MarshalJSON() ([]byte, error) {
return json.Marshal(bi.String())
}
func (bi *BigInt) UnmarshalJSON(b []byte) error {
var s string
if err := json.Unmarshal(b, &s); err != nil {
return err
}
i, ok := big.NewInt(0).SetString(s, 10)
if !ok {
if string(s) == "<nil>" {
return nil
}
return fmt.Errorf("failed to parse bigint string")
}
bi.Int = i
return nil
}