added

vendor/github.com/glycerine/zygomys/zygo/blake2.go

@@ -0,0 +1,26 @@
+package zygo
+
+import (
+	"encoding/binary"
+	"github.com/glycerine/blake2b"
+)
+
+// Blake2bUint64 returns an 8 byte BLAKE2b cryptographic
+// hash of the raw.
+//
+// we're using the pure go: https://github.com/dchest/blake2b
+//
+// but the C-wrapped refence may be helpful as well --
+//
+// reference: https://godoc.org/github.com/codahale/blake2
+// reference: https://blake2.net/
+// reference: https://tools.ietf.org/html/rfc7693
+//
+func Blake2bUint64(raw []byte) uint64 {
+	cfg := &blake2b.Config{Size: 8}
+	h, err := blake2b.New(cfg)
+	panicOn(err)
+	h.Write(raw)
+	by := h.Sum(nil)
+	return binary.LittleEndian.Uint64(by[:8])
+}