Re: [PATCH] midx: use buffered I/O to talk to pack-objects

[Chris Torek <chris.torek@gmail.com>]

On Sun, Aug 2, 2020 at 7:40 AM René Scharfe <l.s.r@web.de> wrote:
> @@ -1443,10 +1446,15 @@ int midx_repack(struct repository *r, const char *object_dir, size_t batch_size,
>                         continue;
>
>                 nth_midxed_object_oid(&oid, m, i);
> -               xwrite(cmd.in, oid_to_hex(&oid), the_hash_algo->hexsz);
> -               xwrite(cmd.in, "\n", 1);
> +               fprintf(cmd_in, "%s\n", oid_to_hex(&oid));
> +       }
> +
> +       if (fclose(cmd_in)) {
> +               error_errno(_("could not close stdin of pack-objects"));
> +               result = 1;
> +               finish_command(&cmd);
> +               goto cleanup;
>         }
> -       close(cmd.in);
>
>         if (finish_command(&cmd)) {
>                 error(_("could not finish pack-objects"));
> --
> 2.28.0

Here, we don't have any explicit errno checking, but
of course error_errno() uses errno.  This too needs
an ferror() (or fflush()) test before the final fclose(),
and then we just need to use plain error().  Otherwise
you'll need the clumsier test-after-each-fprintf() and
an explicit final fflush()-and-test.

Chris