add Buffer.compare, #compare, #equals

diff --git a/index.js b/index.js
index d687ce22ef1aa68645fd3d708e6561e5d87dc355..c10884771d3522571e83ec4884516d4d2cfc7bf3 100644 (file)
--- a/index.js
+++ b/index.js
@@ -192,6 +192,24 @@ Buffer.concat = function (list, totalLength) {
   return buf
 }
 
+Buffer.compare = function (a, b) {
+  assert(Buffer.isBuffer(a) && Buffer.isBuffer(b), 'Arguments must be Buffers')
+  var x = a.length
+  var y = b.length
+  for (var i = 0, len = Math.min(x, y); i < len && a[i] === b[i]; i++) {}
+  if (i !== len) {
+    x = a[i]
+    y = b[i]
+  }
+  if (x < y) {
+    return -1
+  }
+  if (y < x) {
+    return 1
+  }
+  return 0
+}
+
 // BUFFER INSTANCE METHODS
 // =======================
 
@@ -358,6 +376,17 @@ Buffer.prototype.toJSON = function () {
   }
 }
 
+Buffer.prototype.equals = function (b) {
+  assert(Buffer.isBuffer(b), 'Argument must be a Buffer')
+  console.log(this, b)
+  return Buffer.compare(this, b) === 0
+}
+
+Buffer.prototype.compare = function (b) {
+  assert(Buffer.isBuffer(b), 'Argument must be a Buffer')
+  return Buffer.compare(this, b)
+}
+
 // copy(targetBuffer, targetStart=0, sourceStart=0, sourceEnd=buffer.length)
 Buffer.prototype.copy = function (target, target_start, start, end) {
   var source = this
@@ -944,6 +973,8 @@ Buffer._augment = function (arr) {
   arr.toString = BP.toString
   arr.toLocaleString = BP.toString
   arr.toJSON = BP.toJSON
+  arr.equals = BP.equals
+  arr.compare = BP.compare
   arr.copy = BP.copy
   arr.slice = BP.slice
   arr.readUInt8 = BP.readUInt8