19 var hashJsonLengthErr = errors.New("common: unmarshalJSON failed: hash must be exactly 32 bytes")
25 func BytesToHash(b []byte) Hash {
30 func StringToHash(s string) Hash { return BytesToHash([]byte(s)) }
31 func BigToHash(b *big.Int) Hash { return BytesToHash(b.Bytes()) }
32 func HexToHash(s string) Hash { return BytesToHash(FromHex(s)) }
34 // Don't use the default 'String' method in case we want to overwrite
36 // Get the string representation of the underlying hash
37 func (h Hash) Str() string { return string(h[:]) }
38 func (h Hash) Bytes() []byte { return h[:] }
39 func (h Hash) Big() *big.Int { return Bytes2Big(h[:]) }
40 func (h Hash) Hex() string { return "0x" + Bytes2Hex(h[:]) }
42 // UnmarshalJSON parses a hash in its hex from to a hash.
43 func (h *Hash) UnmarshalJSON(input []byte) error {
45 if length >= 2 && input[0] == '"' && input[length-1] == '"' {
46 input = input[1 : length-1]
48 // strip "0x" for length check
49 if len(input) > 1 && strings.ToLower(string(input[:2])) == "0x" {
53 // validate the length of the input hash
54 if len(input) != HashLength*2 {
55 return hashJsonLengthErr
57 h.SetBytes(FromHex(string(input)))
61 // Serialize given hash to JSON
62 func (h Hash) MarshalJSON() ([]byte, error) {
63 return json.Marshal(h.Hex())
66 // Sets the hash to the value of b. If b is larger than len(h) it will panic
67 func (h *Hash) SetBytes(b []byte) {
69 b = b[len(b)-HashLength:]
72 copy(h[HashLength-len(b):], b)
75 // Set string `s` to h. If s is larger than len(h) it will panic
76 func (h *Hash) SetString(s string) { h.SetBytes([]byte(s)) }
79 func (h *Hash) Set(other Hash) {
80 for i, v := range other {
85 // Generate implements testing/quick.Generator.
86 func (h Hash) Generate(rand *rand.Rand, size int) reflect.Value {
87 m := rand.Intn(len(h))
88 for i := len(h) - 1; i > m; i-- {
89 h[i] = byte(rand.Uint32())
91 return reflect.ValueOf(h)
94 func EmptyHash(h Hash) bool {