From 73263c3d044c1d7bd8e2a74a302817fd2c05b405 Mon Sep 17 00:00:00 2001
From: cyberman54 <cyberman@obh.snafu.de>
Date: Sun, 27 Dec 2020 23:43:45 +0100
Subject: [PATCH] externalize hash code to library

---
 include/hash.h      |  2 +-
 platformio_orig.ini |  1 +
 src/hash.cpp        | 52 +++------------------------------------------
 3 files changed, 5 insertions(+), 50 deletions(-)

diff --git a/include/hash.h b/include/hash.h
index 2caa6133..cfd96ce7 100644
--- a/include/hash.h
+++ b/include/hash.h
@@ -2,7 +2,7 @@
 #define _HASH_H
 
 #include <Arduino.h>
-#include <inttypes.h>
+#include <RokkitHash.h>
 
 uint32_t IRAM_ATTR hash(const char *data, int len);
 
diff --git a/platformio_orig.ini b/platformio_orig.ini
index 3b013c97..27e0e688 100644
--- a/platformio_orig.ini
+++ b/platformio_orig.ini
@@ -79,6 +79,7 @@ lib_deps_sensors =
     boschsensortec/BSEC Software Library @ 1.6.1480
     https://github.com/ricki-z/SDS011.git
 lib_deps_basic =
+    https://github.com/SukkoPera/Arduino-Rokkit-Hash.git
     bblanchon/ArduinoJson @ ^6
     jchristensen/Timezone @ ^1.2.4
     makuna/RTC @ ^2.3.5
diff --git a/src/hash.cpp b/src/hash.cpp
index 172dca5d..32e8b1c5 100644
--- a/src/hash.cpp
+++ b/src/hash.cpp
@@ -36,55 +36,9 @@
 
 #include "hash.h"
 
-uint32_t IRAM_ATTR rokkit(const char *data, int len) {
-  uint32_t hash, tmp;
-  int rem;
-
-  if (len <= 0 || data == 0)
-    return 0;
-  hash = len;
-  rem = len & 3;
-  len >>= 2;
-
-  /* Main loop */
-  while (len > 0) {
-    hash += *((uint16_t *)data);
-    tmp = (*((uint16_t *)(data + 2)) << 11) ^ hash;
-    hash = (hash << 16) ^ tmp;
-    data += 2 * 2;
-    hash += hash >> 11;
-    len--;
-  }
-
-  /* Handle end cases */
-  switch (rem) {
-  case 3:
-    hash += *((uint16_t *)data);
-    hash ^= hash << 16;
-    hash ^= ((uint32_t)data[2]) << 18;
-    hash += hash >> 11;
-    break;
-  case 2:
-    hash += *((uint16_t *)data);
-    hash ^= hash << 11;
-    hash += hash >> 17;
-    break;
-  case 1:
-    hash += (signed char)*data;
-    hash ^= hash << 10;
-    hash += hash >> 1;
-  }
-
-  /* Force "avalanching" of final 127 bits */
-  hash ^= hash << 3;
-  hash += hash >> 5;
-  hash ^= hash << 4;
-  hash += hash >> 17;
-  hash ^= hash << 25;
-  hash += hash >> 6;
-
-  return hash;
-}
+#ifdef ROKKIT_ENABLE_8BIT_OPTIMIZATIONS
+#undef ROKKIT_ENABLE_8BIT_OPTIMIZATIONS
+#endif
 
 uint32_t IRAM_ATTR hash(const char *data, int len) {
   return rokkit(data, len);