Initial release

1 files changed, 24 insertions, 0 deletions

diff --git a/lru.go b/lru.go
new file mode 100644
index 0000000..e0a386f
--- /dev/null
+++ b/lru.go
@@ -0,0 +1,24 @@
+package main
+
+import "encoding/binary"
+
+const (
+	// FNV-1a
+	offset32 = uint32(2166136261)
+	prime32  = uint32(16777619)
+)
+
+func hashPacket(p PacketTruncated) uint32 {
+	h := offset32
+	b := make([]byte, 12)
+	binary.BigEndian.PutUint32(b[0:4], p.To)
+	binary.BigEndian.PutUint32(b[4:8], p.From)
+	binary.BigEndian.PutUint32(b[8:12], p.ID)
+	for ; len(b) >= 4; b = b[4:] {
+		h = (h ^ uint32(b[0])) * prime32
+		h = (h ^ uint32(b[1])) * prime32
+		h = (h ^ uint32(b[2])) * prime32
+		h = (h ^ uint32(b[3])) * prime32
+	}
+	return h
+}