1 files changed, 28 insertions, 22 deletions
diff --git a/lib/buffer.js b/lib/buffer.js
index dfd79e6290..de0ab040dd 100644
--- a/lib/buffer.js
+++ b/lib/buffer.js
@@ -202,40 +202,46 @@ Buffer.prototype.parent = undefined;
 
 // toString(encoding, start=0, end=buffer.length)
 Buffer.prototype.toString = function(encoding, start, end) {
-  encoding = !!encoding ? (encoding + '').toLowerCase() : 'utf8';
+  var loweredCase = false;
 
-  start = ~~start;
-  end = util.isUndefined(end) ? this.length : ~~end;
+  start = start >>> 0;
+  end = util.isUndefined(end) ? this.length : end >>> 0;
 
+  if (!encoding) encoding = 'utf8';
   if (start < 0) start = 0;
   if (end > this.length) end = this.length;
   if (end <= start) return '';
 
-  switch (encoding) {
-    case 'hex':
-      return this.hexSlice(start, end);
+  while (true) {
+    switch (encoding) {
+      case 'hex':
+        return this.hexSlice(start, end);
 
-    case 'utf8':
-    case 'utf-8':
-      return this.utf8Slice(start, end);
+      case 'utf8':
+      case 'utf-8':
+        return this.utf8Slice(start, end);
 
-    case 'ascii':
-      return this.asciiSlice(start, end);
+      case 'ascii':
+        return this.asciiSlice(start, end);
 
-    case 'binary':
-      return this.binarySlice(start, end);
+      case 'binary':
+        return this.binarySlice(start, end);
 
-    case 'base64':
-      return this.base64Slice(start, end);
+      case 'base64':
+        return this.base64Slice(start, end);
 
-    case 'ucs2':
-    case 'ucs-2':
-    case 'utf16le':
-    case 'utf-16le':
-      return this.ucs2Slice(start, end);
+      case 'ucs2':
+      case 'ucs-2':
+      case 'utf16le':
+      case 'utf-16le':
+        return this.ucs2Slice(start, end);
 
-    default:
-      throw new TypeError('Unknown encoding: ' + encoding);
+      default:
+        if (loweredCase)
+          throw new TypeError('Unknown encoding: ' + encoding);
+        encoding = (encoding + '').toLowerCase();
+        loweredCase = true;
+    }
   }
 };