1 files changed, 101 insertions, 0 deletions
diff --git a/src/hash/murmur.c b/src/hash/murmur.c
new file mode 100644
index 0000000..9d913db
--- /dev/null
+++ b/src/hash/murmur.c
@@ -0,0 +1,101 @@
+#include "../i_util.h"
+#include "../crypto.h"
+#include <stdio.h>
+#include <stdint.h>
+
+uint32_t murmur1_32(uint8_t* in, size_t len, uint32_t seed){
+    uint32_t m = 0xc6a4a793;
+    uint32_t hash = seed ^ (len * m);
+
+    for(;len >= 4; len-=4){
+        hash+=*(uint32_t*)in;
+        hash*=m;
+        hash^=hash >> 16;
+
+        in+=4;
+    }
+
+    switch(len){
+        case 3:
+            hash+=in[2]<<16;
+        case 2:
+            hash+=in[1]<<8;
+        case 1:
+            hash+=in[0];
+            hash*=m;
+            hash^=hash>>16;
+            break;
+    }
+
+    hash*=m;
+    hash^=hash>>10;
+    hash*=m;
+    hash^=hash>>17;
+
+    return hash;
+}
+
+uint32_t murmur2_32(uint8_t* in, size_t len, uint32_t seed){
+    uint32_t m = 0x5bd1e995;
+    uint32_t hash = seed ^ len;
+
+    for(;len >= 4; len-=4){
+        uint32_t k = *(uint32_t*)in;
+
+        k*=m;
+        k^=k>>24;
+        k*=m;
+
+        hash*=m;
+        hash^=k;
+
+        in+=4;
+    }
+
+    switch(len){
+        case 3:
+            hash+=in[2]<<16;
+        case 2:
+            hash+=in[1]<<8;
+        case 1:
+            hash+=in[0];
+            hash*=m;
+            break;
+    }
+
+    hash^=hash>>13;
+    hash*=m;
+    hash^=hash>>15;
+
+    return hash;
+}
+
+int l_murmur1_32(lua_State* L){ 
+  size_t len = 0;
+  uint8_t* a = (uint8_t*)luaL_checklstring(L, 1, &len);
+  int argv = lua_gettop(L);
+  uint64_t seed = 0;
+  if(argv > 1) seed = luaL_checkinteger(L, 2);
+
+  char digest[64];
+
+  uint64_t u = murmur1_32(a, len, seed);
+  sprintf(digest,"%08lx",u);
+  lua_pushstring(L, digest);
+  return 1;
+}
+
+int l_murmur2_32(lua_State* L){ 
+  size_t len = 0;
+  uint8_t* a = (uint8_t*)luaL_checklstring(L, 1, &len);
+  int argv = lua_gettop(L);
+  uint64_t seed = 0;
+  if(argv > 1) seed = luaL_checkinteger(L, 2);
+
+  char digest[64];
+
+  uint64_t u = murmur2_32(a, len, seed);
+  sprintf(digest,"%08lx",u);
+  lua_pushstring(L, digest);
+  return 1;
+}