Hulk did something

[bytom/vapor.git] / crypto / sha3pool / pool.go

diff --git a/crypto/sha3pool/pool.go b/crypto/sha3pool/pool.go
new file mode 100644 (file)
index 0000000..ca69b6a
--- /dev/null
+++ b/crypto/sha3pool/pool.go
@@ -0,0 +1,31 @@
+// Package sha3pool is a freelist for SHA3-256 hash objects.
+package sha3pool
+
+import (
+       "sync"
+
+       "golang.org/x/crypto/sha3"
+)
+
+var pool = &sync.Pool{New: func() interface{} { return sha3.New256() }}
+
+// Get256 returns an initialized SHA3-256 hash ready to use.
+// It is like sha3.New256 except it uses the freelist.
+// The caller should call Put256 when finished with the returned object.
+func Get256() sha3.ShakeHash {
+       return pool.Get().(sha3.ShakeHash)
+}
+
+// Put256 resets h and puts it in the freelist.
+func Put256(h sha3.ShakeHash) {
+       h.Reset()
+       pool.Put(h)
+}
+
+// Sum256 uses a ShakeHash from the pool to sum into hash.
+func Sum256(hash, data []byte) {
+       h := Get256()
+       h.Write(data)
+       h.Read(hash)
+       Put256(h)
+}