[PATCH 2/3] libfile: Add copy_fd()

[Trent Piepho]

On Tue, Jun 22, 2021 at 9:34 PM Sascha Hauer <s.hauer at pengutronix.de> wrote:
> +       while (1) {
> +               int now, wr;
> +
> +               now = read(in, buf, bs);
> +               if (now < 0) {
> +                       ret = now;
> +                       goto err;
> +               }
> +
> +               if (!now)
> +                       break;
> +
> +               wr = write_full(out, buf, now);
> +               if (wr < 0) {
> +                       ret = wr;
> +                       goto err;
> +               }
> +       }
> +
> +       ret = 0;
> +err:
> +        free(buf);
> +
> +       return ret;

This can be quite a bit shorter:

while (1) {
       ret = read(in, buf, bs);
       if (ret <= 0)
               break;
       ret = write_full(out, buf, ret);
       if (ret < 0)
               break;
}
free(buf)
return ret;