Merge pull request #201 from Bytom/v0.1

[bytom/vapor.git] / vendor / github.com / bytom / common / types.go

diff --git a/vendor/github.com/bytom/common/types.go b/vendor/github.com/bytom/common/types.go
new file mode 100644 (file)
index 0000000..a6ac9fa
--- /dev/null
+++ b/vendor/github.com/bytom/common/types.go
@@ -0,0 +1,92 @@
+package common
+
+import (
+       _ "encoding/hex"
+       "encoding/json"
+       "errors"
+       "math/big"
+       "math/rand"
+       "reflect"
+       "strings"
+)
+
+const (
+       HashLength       = 32
+       AddressLength    = 42
+       PubkeyHashLength = 20
+)
+
+var hashJsonLengthErr = errors.New("common: unmarshalJSON failed: hash must be exactly 32 bytes")
+
+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()) }
+
+// Don't use the default 'String' method in case we want to overwrite
+
+// 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) Hex() string   { return "0x" + Bytes2Hex(h[:]) }
+
+// UnmarshalJSON parses a hash in its hex from to a hash.
+func (h *Hash) UnmarshalJSON(input []byte) error {
+       length := len(input)
+       if length >= 2 && input[0] == '"' && input[length-1] == '"' {
+               input = input[1 : length-1]
+       }
+       // strip "0x" for length check
+       if len(input) > 1 && strings.ToLower(string(input[:2])) == "0x" {
+               input = input[2:]
+       }
+
+       // validate the length of the input hash
+       if len(input) != HashLength*2 {
+               return hashJsonLengthErr
+       }
+       h.SetBytes(FromHex(string(input)))
+       return nil
+}
+
+// Serialize given hash to JSON
+func (h Hash) MarshalJSON() ([]byte, error) {
+       return json.Marshal(h.Hex())
+}
+
+// Sets the hash to the value of b. If b is larger than len(h) it will panic
+func (h *Hash) SetBytes(b []byte) {
+       if len(b) > len(h) {
+               b = b[len(b)-HashLength:]
+       }
+
+       copy(h[HashLength-len(b):], b)
+}
+
+// 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{}
+}