From 5a4db558980be6bec1f4166d0eebf8524fddb791 Mon Sep 17 00:00:00 2001
From: Leonid Evdokimov <leon@darkk.net.ru>
Date: Fri, 27 Sep 2024 13:04:14 +0300
Subject: [PATCH] FNV128: fix shift UB and ensure that the test vector match

The test vectors are `golden128` from
https://github.com/golang/go/blob/master/src/hash/fnv/fnv_test.go

FNV128("") =    6c62272e07bb014262b821756295c58d
FNV128("a") =   d228cb69101a8caf78912b704e4a141e
FNV128("ab") =  0880945aeeab1be95aa073305526c088
FNV128("abc") = a68bb2a4348b5822836dbc78c6aee73b
---
 Hashes.cpp | 2 +-
 main.cpp   | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/Hashes.cpp b/Hashes.cpp
index 55c81fc2..f02bbb53 100644
--- a/Hashes.cpp
+++ b/Hashes.cpp
@@ -388,7 +388,7 @@ FNV128(uint64_t buf[2], const char *key, int len, uint64_t seed)
     uint64_t s0 = multhi;                 // high
     uint64_t s1 = prime128Lower * buf[1]; // low
     
-    s0 += buf[1] << (prime128Shift + prime128Lower * buf[0]);
+    s0 += (buf[1] << prime128Shift) + prime128Lower * buf[0];
 
     // Update the values
     buf[1] = s1;
diff --git a/main.cpp b/main.cpp
index 386af516..8cc72027 100644
--- a/main.cpp
+++ b/main.cpp
@@ -276,7 +276,7 @@ HashInfo g_hashes[] =
   {0x811c9dc5, 0x23d4a49d} /* !! */ },
 { FNV64a_test,          64, 0x103455FC, "FNV64",       "Fowler-Noll-Vo hash, 64-bit", POOR,
   {0x811c9dc5, 0xcbf29ce4, 0x84222325, 0xcbf29ce484222325} /* TODO */},
-{ FNV128_test,         128, 0xBCAA1426, "FNV128",      "Go variant of FNV, 128-bit", POOR, {} },
+{ FNV128_test,         128, 0xC6FF4526, "FNV128",      "Go variant of FNV, 128-bit", POOR, {} },
 #endif
 { FNV2_test,    __WORDSIZE, FNV2_VERIF, "FNV2",        "wordwise FNV", POOR, {} },
 { fletcher2_test,       64, 0x890767C0, "fletcher2",   "fletcher2 ZFS", POOR, {0UL} /* !! */ },