stream: improve read() performance more

PR-URL: #28989
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Michaël Zasso <targos@protonmail.com>
Reviewed-By: Trivikram Kamat <trivikr.dev@gmail.com>

Author: mscdex

lib/internal/streams/buffer_list.js

@@ -139,7 +139,10 @@ module.exports = class BufferList {
     while (p = p.next) {
       const buf = p.data;
       const nb = (n > buf.length ? buf.length : n);
-      buf.copy(ret, ret.length - n, 0, nb);
+      if (nb === buf.length)
+        ret.set(buf, ret.length - n);
+      else
+        ret.set(new Uint8Array(buf.buffer, buf.byteOffset, nb), ret.length - n);
       n -= nb;
       if (n === 0) {
         if (nb === buf.length) {