update node

node/node_modules/ws/lib/buffer-util.js

@@ -1,5 +1,7 @@
 'use strict';
 
+const { EMPTY_BUFFER } = require('./constants');
+
 /**
  * Merges an array of buffers into a new buffer.
  *
@@ -8,7 +10,10 @@
  * @return {Buffer} The resulting buffer
  * @public
  */
-function concat (list, totalLength) {
+function concat(list, totalLength) {
+  if (list.length === 0) return EMPTY_BUFFER;
+  if (list.length === 1) return list[0];
+
   const target = Buffer.allocUnsafe(totalLength);
   var offset = 0;
 
@@ -31,7 +36,7 @@ function concat (list, totalLength) {
  * @param {Number} length The number of bytes to mask.
  * @public
  */
-function _mask (source, mask, output, offset, length) {
+function _mask(source, mask, output, offset, length) {
   for (var i = 0; i < length; i++) {
     output[offset + i] = source[i] ^ mask[i & 3];
   }
@@ -44,7 +49,7 @@ function _mask (source, mask, output, offset, length) {
  * @param {Buffer} mask The mask to use
  * @public
  */
-function _unmask (buffer, mask) {
+function _unmask(buffer, mask) {
   // Required until https://github.com/nodejs/node/issues/9006 is resolved.
   const length = buffer.length;
   for (var i = 0; i < length; i++) {
@@ -52,21 +57,88 @@ function _unmask (buffer, mask) {
   }
 }
 
+/**
+ * Converts a buffer to an `ArrayBuffer`.
+ *
+ * @param {Buffer} buf The buffer to convert
+ * @return {ArrayBuffer} Converted buffer
+ * @public
+ */
+function toArrayBuffer(buf) {
+  if (buf.byteLength === buf.buffer.byteLength) {
+    return buf.buffer;
+  }
+
+  return buf.buffer.slice(buf.byteOffset, buf.byteOffset + buf.byteLength);
+}
+
+/**
+ * Converts `data` to a `Buffer`.
+ *
+ * @param {*} data The data to convert
+ * @return {Buffer} The buffer
+ * @throws {TypeError}
+ * @public
+ */
+function toBuffer(data) {
+  toBuffer.readOnly = true;
+
+  if (Buffer.isBuffer(data)) return data;
+
+  var buf;
+
+  if (data instanceof ArrayBuffer) {
+    buf = Buffer.from(data);
+  } else if (ArrayBuffer.isView(data)) {
+    buf = viewToBuffer(data);
+  } else {
+    buf = Buffer.from(data);
+    toBuffer.readOnly = false;
+  }
+
+  return buf;
+}
+
+/**
+ * Converts an `ArrayBuffer` view into a buffer.
+ *
+ * @param {(DataView|TypedArray)} view The view to convert
+ * @return {Buffer} Converted view
+ * @private
+ */
+function viewToBuffer(view) {
+  const buf = Buffer.from(view.buffer);
+
+  if (view.byteLength !== view.buffer.byteLength) {
+    return buf.slice(view.byteOffset, view.byteOffset + view.byteLength);
+  }
+
+  return buf;
+}
+
 try {
   const bufferUtil = require('bufferutil');
   const bu = bufferUtil.BufferUtil || bufferUtil;
 
   module.exports = {
-    mask (source, mask, output, offset, length) {
+    concat,
+    mask(source, mask, output, offset, length) {
       if (length < 48) _mask(source, mask, output, offset, length);
       else bu.mask(source, mask, output, offset, length);
     },
-    unmask (buffer, mask) {
+    toArrayBuffer,
+    toBuffer,
+    unmask(buffer, mask) {
       if (buffer.length < 32) _unmask(buffer, mask);
       else bu.unmask(buffer, mask);
-    },
-    concat
+    }
   };
 } catch (e) /* istanbul ignore next */ {
-  module.exports = { concat, mask: _mask, unmask: _unmask };
+  module.exports = {
+    concat,
+    mask: _mask,
+    toArrayBuffer,
+    toBuffer,
+    unmask: _unmask
+  };
 }