hash: add hash_fast_murmur()

baresip · Feb 1, 2023 · df1eb59 · df1eb59
1 parent 059b9d5
commit df1eb59
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diff --git a/include/re_hash.h b/include/re_hash.h
@@ -33,3 +33,4 @@ uint32_t hash_joaat_pl(const struct pl *pl);
 uint32_t hash_joaat_pl_ci(const struct pl *pl);
 uint32_t hash_fast(const char *k, size_t len);
 uint32_t hash_fast_str(const char *str);
+uint32_t hash_fast_murmur(uint32_t key);
diff --git a/src/hash/func.c b/src/hash/func.c
@@ -185,3 +185,22 @@ uint32_t hash_fast_str(const char *str)
 
 	return h;
 }
+
+
+/**
+ * Calculate hash-value using modified murmur (fast finalize part)
+ *
+ * @param key    Key value
+ *
+ * @return Calculated hash-value
+ */
+uint32_t hash_fast_murmur(uint32_t key)
+{
+	key ^= key >> 16;
+	key *= 0x85ebca6b;
+	key ^= key >> 13;
+	key *= 0xc2b2ae35;
+	key ^= key >> 16;
+
+	return key;
+}