Initial version.

1 files changed, 84 insertions, 0 deletions

diff --git a/src/nxt_murmur_hash.c b/src/nxt_murmur_hash.c
new file mode 100644
index 00000000..e9adabfa
--- /dev/null
+++ b/src/nxt_murmur_hash.c
@@ -0,0 +1,84 @@
+
+/*
+ * The code is based on the code by Austin Appleby,
+ * released to the public domain.
+ */
+
+#include <nxt_main.h>
+
+
+uint32_t
+nxt_murmur_hash2(const void *data, size_t len)
+{
+    uint32_t        h, k;
+    const u_char    *p;
+    const uint32_t  m = 0x5bd1e995;
+
+    p = data;
+    h = 0 ^ (uint32_t) len;
+
+    while (len >= 4) {
+        k  = p[0];
+        k |= p[1] << 8;
+        k |= p[2] << 16;
+        k |= p[3] << 24;
+
+        k *= m;
+        k ^= k >> 24;
+        k *= m;
+
+        h *= m;
+        h ^= k;
+
+        p += 4;
+        len -= 4;
+    }
+
+    switch (len) {
+    case 3:
+        h ^= p[2] << 16;
+    case 2:
+        h ^= p[1] << 8;
+    case 1:
+        h ^= p[0];
+        h *= m;
+    }
+
+    h ^= h >> 13;
+    h *= m;
+    h ^= h >> 15;
+
+    return h;
+}
+
+
+/* The MurmurHash2 for fixed 4 byte length. */
+
+uint32_t
+nxt_murmur_hash2_uint32(const void *data)
+{
+    uint32_t        h, k;
+    const u_char    *p;
+    const uint32_t  m = 0x5bd1e995;
+
+    p = data;
+
+    k  = p[0];
+    k |= p[1] << 8;
+    k |= p[2] << 16;
+    k |= p[3] << 24;
+
+    k *= m;
+    k ^= k >> 24;
+    k *= m;
+
+    h = 0 ^ 4;
+    h *= m;
+    h ^= k;
+
+    h ^= h >> 13;
+    h *= m;
+    h ^= h >> 15;
+
+    return h;
+}