Re: [Libguestfs] [nbdkit PATCH v2] server: Don't assert on send if client hangs up early

26 Feb 2023


      On 2/24/23 23:59, Eric Blake wrote:
...
@@ -752,14 +742,15 @@ protocol_recv_request_send_reply (void)
       (cmd == NBD_CMD_READ || cmd == NBD_CMD_BLOCK_STATUS)) {
     if (!error) {
       if (cmd == NBD_CMD_READ)
-        send_structured_reply_read (request.handle, cmd, buf, count, offset);
+        return send_structured_reply_read (request.handle, cmd, buf, count,
+                                           offset);
       else /* NBD_CMD_BLOCK_STATUS */
-        send_structured_reply_block_status (request.handle, cmd, flags,
-                                            count, offset, extents);
+        return send_structured_reply_block_status (request.handle, cmd, flags,
+                                                   count, offset, extents);
     }
     else
-      send_structured_reply_error (request.handle, cmd, flags, error);
+      return send_structured_reply_error (request.handle, cmd, flags, error);
   }
   else
-    send_simple_reply (request.handle, cmd, flags, buf, count, error);
+    return send_simple_reply (request.handle, cmd, flags, buf, count, error);
 }
I think this would look better:

  if (!conn->structured_replies ||
      (cmd != NBD_CMD_READ && cmd != NBD_CMD_BLOCK_STATUS))
    return send_simple_reply (request.handle, cmd, flags, buf, count, error);

  if (error) {
    return send_structured_reply_error (request.handle, cmd, flags, error);

  if (cmd == NBD_CMD_READ)
    return send_structured_reply_read (request.handle, cmd, buf, count, offset);

  /* NBD_CMD_BLOCK_STATUS */
  return send_structured_reply_block_status (request.handle, cmd, flags,
                                             count, offset, extents);

Either way:

Reviewed-by: Laszlo Ersek <lersek@redhat.com>

    