Short sftp packet!

[Rafael Hovhannisyan <psrafo@xxxxxxxxx>]

Hello everybody.

I have a problem, which I can't understand by myself. When I am trying to
write long files(bigger than 255 kb) via sftp_write function, I am getting
an error message(Short sftp packet!); but when file was created/updated on
remote server, it was with zero bytes.

Code: https://github.com/psrafo/justup/blob/master/src/justup.c#L330