src: clean up `req.bytes` tracking

Simply always tell the caller how many bytes were written, rather
than letting them track it.

In the case of writing a string, also keep track of the bytes
written by the earlier `DoTryWrite()`.

Refs: https://github.com/nodejs/node/issues/19562

PR-URL: https://github.com/nodejs/node/pull/19551
Reviewed-By: James M Snell <jasnell@gmail.com>

1 files changed, 5 insertions, 3 deletions

diff --git a/src/stream_base-inl.h b/src/stream_base-inl.h
index 35e49dfea2..392dc2c87c 100644
--- a/src/stream_base-inl.h
+++ b/src/stream_base-inl.h
@@ -194,13 +194,15 @@ inline StreamWriteResult StreamBase::Write(
   Environment* env = stream_env();
   int err;
 
+  size_t total_bytes = 0;
   for (size_t i = 0; i < count; ++i)
-    bytes_written_ += bufs[i].len;
+    total_bytes += bufs[i].len;
+  bytes_written_ += total_bytes;
 
   if (send_handle == nullptr) {
     err = DoTryWrite(&bufs, &count);
     if (err != 0 || count == 0) {
-      return StreamWriteResult { false, err, nullptr };
+      return StreamWriteResult { false, err, nullptr, total_bytes };
     }
   }
 
@@ -230,7 +232,7 @@ inline StreamWriteResult StreamBase::Write(
     ClearError();
   }
 
-  return StreamWriteResult { async, err, req_wrap };
+  return StreamWriteResult { async, err, req_wrap, total_bytes };
 }
 
 template <typename OtherBase>