From 339adb3600c15d3d61320ed729bd5f002f7d7e94 Mon Sep 17 00:00:00 2001
From: Joseph Werle <joseph.werle@gmail.com>
Date: Mon, 5 May 2014 08:57:14 -0400
Subject: init

---
 Makefile     | 12 ++++++++++
 murmurhash.c | 73 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 murmurhash.h | 18 +++++++++++++++
 package.json |  9 ++++++++
 test.c       | 57 +++++++++++++++++++++++++++++++++++++++++++++++
 5 files changed, 169 insertions(+)
 create mode 100644 Makefile
 create mode 100644 murmurhash.c
 create mode 100644 murmurhash.h
 create mode 100644 package.json
 create mode 100644 test.c

diff --git a/Makefile b/Makefile
new file mode 100644
index 0000000..5a87aa9
--- /dev/null
+++ b/Makefile
@@ -0,0 +1,12 @@
+
+SRC = murmurhash.c
+CFLAGS += -std=c99 -Wall -I.
+
+clean:
+	rm -f test
+
+test:
+	$(CC) test.c $(SRC) $(CFLAGS) -o test
+	./test
+
+.PHONY: test
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;
+}
diff --git a/murmurhash.h b/murmurhash.h
new file mode 100644
index 0000000..48d39bf
--- /dev/null
+++ b/murmurhash.h
@@ -0,0 +1,18 @@
+
+/**
+ * `murmurhash.h' - murmurhash
+ *
+ * copyright (c) 2014 joseph werle <joseph.werle@gmail.com>
+ */
+
+#ifndef MURMURHASH_H
+#define MURMURHASH_H 1
+
+/**
+ *
+ */
+
+uint32_t
+murmurhash (const char *, uint32_t, uint32_t);
+
+#endif
diff --git a/package.json b/package.json
new file mode 100644
index 0000000..940797c
--- /dev/null
+++ b/package.json
@@ -0,0 +1,9 @@
+{
+  "name": "murmurhash",
+  "version": "0.0.1",
+  "repo": "jwerle/murmurhash.c",
+  "description": "MurmurHash3 general hash bashed lookup function implementation",
+  "keywords": ["murmur", "hash", "murmurhash"],
+  "license": "MIT",
+  "src": [ "murmurhash.h", "murmurhash.c" ]
+}
diff --git a/test.c b/test.c
new file mode 100644
index 0000000..27b69ab
--- /dev/null
+++ b/test.c
@@ -0,0 +1,57 @@
+
+/**
+ * `test.c' - murmurhash
+ *
+ * copyright (c) 2014 joseph werle <joseph.werle@gmail.com>
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <inttypes.h>
+#include <assert.h>
+#include <murmurhash.h>
+
+int
+main (void) {
+  uint32_t hash = 0;
+  uint32_t seed = 0;
+
+#define t(str, seed, expected) {                 \
+  uint32_t len = (uint32_t) strlen(str);         \
+  hash = murmurhash(str, len, seed);             \
+  printf(                                        \
+      "['%s'] '%" PRIu32 "' = '%" PRIu32 "'",    \
+      str, (uint32_t) expected, hash);           \
+  assert((uint32_t) expected == hash);           \
+  printf(" ...ok\n");                            \
+}
+
+  seed = 0;
+  t("", seed, 0x00000000);
+  t("0", seed, 0xd271c07f);
+  t("01", seed, 0x61ec6600);
+  t("012", seed, 0xec6cff8c);
+  t("0123", seed, 0xd41994a0);
+  t("01234", seed, 0x19d02170);
+  t("2", seed, 0x0129e217);
+  t("88", seed, 0x7a0040a5);
+
+  t("asdfqwer", seed, 0xa46b5209);
+  t("asdfqwerty", seed, 0xa3cfe04b);
+  t("asd", seed, 0x14570c6f);
+
+  t("Hello", seed, 0x12da77c8);
+  t("Hello1", seed, 0x6357e0a6);
+  t("Hello2", seed, 0xe5ce223e);
+
+  t("hey", seed, 0x12f94418);
+  t("dude", seed, 0xef0487f3);
+  t("test", seed, 0xba6bd213);
+
+
+  seed = 1;
+  t("", seed, 0x514e28b7);
+
+  return 0;
+}
-- 
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