[Libguestfs] [PATCH] convert_linux: translate the first CD-ROM's references in boot conf files

[Richard W.M. Jones]

On Tue, Dec 14, 2021 at 04:17:49PM +0100, Laszlo Ersek wrote:
> +    match cdroms with
> +    | _ :: _ :: _ -> warning (f_"multiple CD-ROMs found; translation of \
> +                                 CD-ROM references may be inexact")
> +    | _ -> ();
> +
> +    let map = map @

This part is either wrong or indented incorrectly.  The "let map ..."
part is part of the second branch of the match statement and doesn't
run if the warning is printed.

In any case it's probably better to replace the confusing first match
with something simpler such as:

  if List.length cdroms > 2 then
    warning (f_"multiple CD-ROMs found; translation of CD-ROM references may be inexact");

The \ is also not necessary in the original since OCaml lets you have
arbitrary length strings over multiple lines (a good thing), plus we
automatically wrap warning and error strings on whitespace.

> +      (match cdroms with
> +       | cdrom :: _ ->
> +           (match (cdrom.s_removable_controller, cdrom.s_removable_slot,
> +                   family, inspect.i_major_version) with
> +            | Some Source_IDE, Some slot, `RHEL_family, v when v <= 5 ->

You can just match to arbitrary depth in single match statements, so
the whole match would become something like:

  let map = map @
    match cdroms with
    | { Some Source_IDE, Some slot, `RHEL_family v } :: _ when v <= 5 ->
           [("hd" ^ drive_name slot, "cdrom")]
    | _ -> [] in

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
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