1 files changed, 73 insertions, 0 deletions
diff --git a/murmurhash.c b/murmurhash.c
new file mode 100644
index 0000000..427b3d2
--- /dev/null
+++ b/murmurhash.c
@@ -0,0 +1,73 @@
+
+/**
+ * `murmurhash.h' - murmurhash
+ *
+ * copyright (c) 2014 joseph werle <joseph.werle@gmail.com>
+ */
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <murmurhash.h>
+
+uint32_t
+murmurhash (const char *key, uint32_t len, uint32_t seed) {
+  uint32_t c1 = 0xcc9e2d51;
+  uint32_t c2 = 0x1b873593;
+  uint32_t r1 = 15;
+  uint32_t r2 = 13;
+  uint32_t m = 5;
+  uint32_t n = 0xe6546b64;
+  uint32_t h = 0;
+  uint32_t k = 0;
+  uint8_t *d = (uint8_t *) key; // 32 bit extract from `key'
+  const uint32_t *chunks = 0;
+  const uint8_t *tail = 0; // tail - last 8 bytes
+  int i = 0;
+  int l = len / 4; // chunk length
+
+  h = seed;
+
+  chunks = (const uint32_t *) (d + l * 4); // body
+  tail = (const uint8_t *) (d + l * 4); // last 8 byte chunk of `key'
+
+  // for each 4 byte chunk of `key'
+  for (i = -l; i != 0; ++i) {
+    // next 4 byte chunk of `key'
+    k = chunks[i];
+
+    // encode next 4 byte chunk of `key'
+    k *= c1;
+    k = (k << r1) | (k >> (32 - r1));
+    k *= c2;
+
+    // append to hash
+    h ^= k;
+    h = (h << r2) | (h >> (32 - r2));
+    h = h * m + n;
+  }
+
+  k = 0;
+
+  // remainder
+  switch (len & 3) { // `len % 4'
+    case 3: k ^= (tail[2] << 16);
+    case 2: k ^= (tail[1] << 8);
+
+    case 1:
+      k ^= tail[0];
+      k *= c1;
+      k = (k << r1) | (k >> (32 - r1));
+      k *= c2;
+      h ^= k;
+  }
+
+  h ^= len;
+
+  h ^= (h >> 16);
+  h *= 0x85ebca6b;
+  h ^= (h >> 13);
+  h *= 0xc2b2ae35;
+  h ^= (h >> 16);
+
+  return h;
+}