fix length calculation error when Buffer as first argument

binding.cc

@@ -21,6 +21,7 @@
 #include <v8.h>
 #include <string.h>
 #include <sstream>
+#include <node_buffer.h>
 #include "city.h"
 #ifdef __SSE4_2__
 #include "citycrc.h"
@@ -30,6 +31,7 @@
 #define MAX_128_HASH_LEN MAX_64_HASH_LEN*2
 
 using namespace v8;
+using node::Buffer;
 
 inline uint32 Uint64High32(const uint64 &x) {
     return (uint32)((x >> 32) & 0xFFFFFFFF);
@@ -235,6 +237,12 @@ node_CityHash64(const Arguments& args) {
     const char* str = *data;
     size_t len = data.length();
 
+    if (Buffer::HasInstance(args[0])) {
+      Local<Object> obj = args[0]->ToObject();
+      str = Buffer::Data(obj);
+      len = Buffer::Length(obj);
+    }
+
     uint64 hash;
 
     if(args_len == 1) {

package.json

@@ -1,6 +1,6 @@
 {
   "name": "cityhash",
-  "version": "0.0.2",
+  "version": "0.0.3",
   "main": "./build/Release/node-cityhash",
   "description": "NodeJS binding for Google CityHash.",
   "dependencies": [ ],

test.js

@@ -88,6 +88,15 @@ assertEqual({
         value: '15738392108067291633'
     }, cityhash.hash64('Hello', 87392039), 'Hash64 for "hello" with seed 87392039');
 
+var b = new Buffer(4)
+b.writeUInt32LE(7771789, 0)
+assertEqual({
+    low: 3883967176,
+    high: 3780832496,
+    uint64: true,
+    value:'16238551925858017992'
+    }, cityhash.hash64(b, "2310915232984335893"), 'Hash64 for Buffer');
+
 assertEqual({
         low: 2569634289,
         high: 3664379964,