+/* Murmurhash by Austin Appleby,
+ * from http://code.google.com/p/smhasher/source/browse/trunk/MurmurHash3.cpp.
+ *
+ * The upstream license there says:
+ *
+ * // MurmurHash3 was written by Austin Appleby, and is placed in the public
+ * // domain. The author hereby disclaims copyright to this source code.
+ *
+ * Murmurhash is faster and higher-quality than the Jenkins lookup3 hash. When
+ * we have a little more familiarity with it, it's probably a good idea to
+ * switch all of OVS to it.
+ *
+ * For now, we have this implementation here for use by code that needs a hash
+ * that is convenient for use one word at a time, since the Jenkins lookup3
+ * hash works three words at a time.
+ *
+ * See mhash_words() for sample usage. */
+
+uint32_t mhash_words(const uint32_t data[], size_t n_words, uint32_t basis);
+
+static inline uint32_t mhash_add(uint32_t hash, uint32_t data)
+{
+ data *= 0xcc9e2d51;
+ data = hash_rot(data, 15);
+ data *= 0x1b873593;
+
+ hash ^= data;
+ hash = hash_rot(hash, 13);
+ return hash * 5 + 0xe6546b64;
+}
+
+static inline uint32_t mhash_finish(uint32_t hash, size_t n)
+{
+ hash ^= n * 4;
+ hash ^= hash_rot(hash, 16);
+ hash *= 0x85ebca6b;
+ hash ^= hash_rot(hash, 13);
+ hash *= 0xc2b2ae35;
+ hash ^= hash_rot(hash, 16);
+ return hash;
+}
+