// Copyright 2015 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
package common
import (
"encoding/hex"
"fmt"
"math/big"
"math/rand"
"reflect"
"github.com/ethereum/go-ethereum/common/hexutil"
"github.com/ethereum/go-ethereum/crypto/sha3"
)
const (
HashLength = 32
AddressLength = 20
)
var (
hashT = reflect.TypeOf(Hash{})
addressT = reflect.TypeOf(Address{})
)
// Hash represents the 32 byte Keccak256 hash of arbitrary data.
type Hash [HashLength]byte
func BytesToHash(b []byte) Hash {
var h Hash
h.SetBytes(b)
return h
}
func StringToHash(s string) Hash { return BytesToHash([]byte(s)) }
func BigToHash(b *big.Int) Hash { return BytesToHash(b.Bytes()) }
func HexToHash(s string) Hash { return BytesToHash(FromHex(s)) }
// Get the string representation of the underlying hash
func (h Hash) Str() string { return string(h[:]) }
func (h Hash) Bytes() []byte { return h[:] }
func (h Hash) Big() *big.Int { return new(big.Int).SetBytes(h[:]) }
func (h Hash) Hex() string { return hexutil.Encode(h[:]) }
// TerminalString implements log.TerminalStringer, formatting a string for console
// output during logging.
func (h Hash) TerminalString() string {
return fmt.Sprintf("%x…%x", h[:3], h[29:])
}
// String implements the stringer interface and is used also by the logger when
// doing full logging into a file.
func (h Hash) String() string {
return h.Hex()
}
// Format implements fmt.Formatter, forcing the byte slice to be formatted as is,
// without going through the stringer interface used for logging.
func (h Hash) Format(s fmt.State, c rune) {
fmt.Fprintf(s, "%"+string(c), h[:])
}
// UnmarshalText parses a hash in hex syntax.
func (h *Hash) UnmarshalText(input []byte) error {
return hexutil.UnmarshalFixedText("Hash", input, h[:])
}
// UnmarshalJSON parses a hash in hex syntax.
func (h *Hash) UnmarshalJSON(input []byte) error {
return hexutil.UnmarshalFixedJSON(hashT, input, h[:])
}
// MarshalText returns the hex representation of h.
func (h Hash) MarshalText() ([]byte, error) {
return hexutil.Bytes(h[:]).MarshalText()
}
// Sets the hash to the value of b. If b is larger than len(h), 'b' will be cropped (from the left).
func (h *Hash) SetBytes(b []byte) {
if len(b) > len(h) {
b = b[len(b)-HashLength:]
}
copy(h[HashLength-len(b):], b)
}
// Set string `s` to h. If s is larger than len(h) s will be cropped (from left) to fit.
func (h *Hash) SetString(s string) { h.SetBytes([]byte(s)) }
// Sets h to other
func (h *Hash) Set(other Hash) {
for i, v := range other {
h[i] = v
}
}
// Generate implements testing/quick.Generator.
func (h Hash) Generate(rand *rand.Rand, size int) reflect.Value {
m := rand.Intn(len(h))
for i := len(h) - 1; i > m; i-- {
h[i] = byte(rand.Uint32())
}
return reflect.ValueOf(h)
}
func EmptyHash(h Hash) bool {
return h == Hash{}
}
// UnprefixedHash allows marshaling a Hash without 0x prefix.
type UnprefixedHash Hash
// UnmarshalText decodes the hash from hex. The 0x prefix is optional.
func (h *UnprefixedHash) UnmarshalText(input []byte) error {
return hexutil.UnmarshalFixedUnprefixedText("UnprefixedHash", input, h[:])
}
// MarshalText encodes the hash as hex.
func (h UnprefixedHash) MarshalText() ([]byte, error) {
return []byte(hex.EncodeToString(h[:])), nil
}
/////////// Address
// Address represents the 20 byte address of an Ethereum account.
type Address [AddressLength]byte
func BytesToAddress(b []byte) Address {
var a Address
a.SetBytes(b)
return a
}
func StringToAddress(s string) Address { return BytesToAddress([]byte(s)) }
func BigToAddress(b *big.Int) Address { return BytesToAddress(b.Bytes()) }
func HexToAddress(s string) Address { return BytesToAddress(FromHex(s)) }
// IsHexAddress verifies whether a string can represent a valid hex-encoded
// Ethereum address or not.
func IsHexAddress(s string) bool {
if hasHexPrefix(s) {
s = s[2:]
}
return len(s) == 2*AddressLength && isHex(s)
}
// Get the string representation of the underlying address
func (a Address) Str() string { return string(a[:]) }
func (a Address) Bytes() []byte { return a[:] }
func (a Address) Big() *big.Int { return new(big.Int).SetBytes(a[:]) }
func (a Address) Hash() Hash { return BytesToHash(a[:]) }
// Hex returns an EIP55-compliant hex string representation of the address.
func (a Address) Hex() string {
unchecksummed := hex.EncodeToString(a[:])
sha := sha3.NewKeccak256()
sha.Write([]byte(unchecksummed))
hash := sha.Sum(nil)
result := []byte(unchecksummed)
for i := 0; i < len(result); i++ {
hashByte := hash[i/2]
if i%2 == 0 {
hashByte = hashByte >> 4
} else {
hashByte &= 0xf
}
if result[i] > '9' && hashByte > 7 {
result[i] -= 32
}
}
return "0x" + string(result)
}
// String implements the stringer interface and is used also by the logger.
func (a Address) String() string {
return a.Hex()
}
// Format implements fmt.Formatter, forcing the byte slice to be formatted as is,
// without going through the stringer interface used for logging.
func (a Address) Format(s fmt.State, c rune) {
fmt.Fprintf(s, "%"+string(c), a[:])
}
// Sets the address to the value of b. If b is larger than len(a) it will panic
func (a *Address) SetBytes(b []byte) {
if len(b) > len(a) {
b = b[len(b)-AddressLength:]
}
copy(a[AddressLength-len(b):], b)
}
// Set string `s` to a. If s is larger than len(a) it will panic
func (a *Address) SetString(s string) { a.SetBytes([]byte(s)) }
// Sets a to other
func (a *Address) Set(other Address) {
for i, v := range other {
a[i] = v
}
}
// MarshalText returns the hex representation of a.
func (a Address) MarshalText() ([]byte, error) {
return hexutil.Bytes(a[:]).MarshalText()
}
// UnmarshalText parses a hash in hex syntax.
func (a *Address) UnmarshalText(input []byte) error {
return hexutil.UnmarshalFixedText("Address", input, a[:])
}
// UnmarshalJSON parses a hash in hex syntax.
func (a *Address) UnmarshalJSON(input []byte) error {
return hexutil.UnmarshalFixedJSON(addressT, input, a[:])
}
// UnprefixedHash allows marshaling an Address without 0x prefix.
type UnprefixedAddress Address
// UnmarshalText decodes the address from hex. The 0x prefix is optional.
func (a *UnprefixedAddress) UnmarshalText(input []byte) error {
return hexutil.UnmarshalFixedUnprefixedText("UnprefixedAddress", input, a[:])
}
// MarshalText encodes the address as hex.
func (a UnprefixedAddress) MarshalText() ([]byte, error) {
return []byte(hex.EncodeToString(a[:])), nil
}
