go-ethereum/ethutil/big.go

76 lines
1.2 KiB
Go

package ethutil
import (
"math/big"
)
var BigInt0 *big.Int = big.NewInt(0)
// True
var BigTrue *big.Int = big.NewInt(1)
// False
var BigFalse *big.Int = big.NewInt(0)
// Big pow
//
// Returns the power of two big integers
func BigPow(a, b int) *big.Int {
c := new(big.Int)
c.Exp(big.NewInt(int64(a)), big.NewInt(int64(b)), big.NewInt(0))
return c
}
// Big
//
// Shortcut for new(big.Int).SetString(..., 0)
func Big(num string) *big.Int {
n := new(big.Int)
n.SetString(num, 0)
return n
}
// BigD
//
// Shortcut for new(big.Int).SetBytes(...)
func BigD(data []byte) *big.Int {
n := new(big.Int)
n.SetBytes(data)
return n
}
// Big to bytes
//
// Returns the bytes of a big integer with the size specified by **base**
// Attempts to pad the byte array with zeros.
func BigToBytes(num *big.Int, base int) []byte {
ret := make([]byte, base/8)
if len(num.Bytes()) > base/8 {
return num.Bytes()
}
return append(ret[:len(ret)-len(num.Bytes())], num.Bytes()...)
}
// Big copy
//
// Creates a copy of the given big integer
func BigCopy(src *big.Int) *big.Int {
return new(big.Int).Set(src)
}
// Big max
//
// Returns the maximum size big integer
func BigMax(x, y *big.Int) *big.Int {
if x.Cmp(y) <= 0 {
return y
}
return x
}