err := d.Decode(v)
	if errors.Is(err, io.EOF) {
		err = &xml.SyntaxError{
			Line: 0,
			Msg:  err.Error(),
		}
	}
	return err
}

// hasContentMD5 returns true if Content-MD5 header is set.
func hasContentMD5(h http.Header) bool {
	_, ok := h[xhttp.ContentMD5]
	return ok
}

// http://docs.aws.amazon.com/AmazonS3/latest/dev/UploadingObjects.html
const (