golang big 代码
文件路径：/src/crypto/internal/boring/bbig/big.go
// Copyright 2022 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package bbig
import (
"crypto/internal/boring"
"math/big"
"unsafe"
)
func Enc(b *big.Int) boring.BigInt {
if b == nil {
return nil
}
x := b.Bits()
if len(x) == 0 {
return boring.BigInt{}
}
return unsafe.Slice((*uint)(&x[0]), len(x))
}
func Dec(b boring.BigInt) *big.Int {
if b == nil {
return nil
}
if len(b) == 0 {
return new(big.Int)
}
x := unsafe.Slice((*big.Word)(&b[0]), len(b))
return new(big.Int).SetBits(x)
}