Avoid infinite loop on malformed message (#1208)

* Avoid infinite loop on malformed message

If handling of such messages is deemed unimportant, `indexOf` is still faster (~40%) and cleaner than a manual loop.

Addresses #1048 to an extent.

* Use indexOf fallback for Node ≤0.12

lib/connection.js

@@ -13,6 +13,21 @@ var util = require('util');
 var Writer = require('buffer-writer');
 var Reader = require('packet-reader');
 
+var indexOf =
+  'indexOf' in Buffer.prototype ?
+    function indexOf(buffer, value, start) {
+      return buffer.indexOf(value, start);
+    } :
+    function indexOf(buffer, value, start) {
+      for (var i = start, len = buffer.length; i < len; i++) {
+        if (buffer[i] === value) {
+          return i;
+        }
+      }
+
+      return -1;
+    };
+
 var TEXT_MODE = 0;
 var BINARY_MODE = 1;
 var Connection = function(config) {
@@ -647,8 +662,9 @@ Connection.prototype.readBytes = function(buffer, length) {
 
 Connection.prototype.parseCString = function(buffer) {
   var start = this.offset;
-  while(buffer[this.offset++] !== 0) { }
-  return buffer.toString(this.encoding, start, this.offset - 1);
+  var end = indexOf(buffer, 0, start);
+  this.offset = end + 1;
+  return buffer.toString(this.encoding, start, end);
 };
 //end parsing methods
 module.exports = Connection;