[Libguestfs] [PATCH 1/2] package handlers: add possibility for final teardown

[Richard W.M. Jones]

On Wed, Sep 17, 2014 at 01:58:24PM +0200, Pino Toscano wrote:
> Add a ph_fini callback to package handlers, so they can do teardown
> operations, if needed, at the very end of the supermin run.
> 
> Currently all of the current package handlers do nothing.
> ---
>  src/dpkg.ml             |  1 +
>  src/package_handler.ml  | 10 ++++++++++
>  src/package_handler.mli | 10 ++++++++++
>  src/pacman.ml           |  1 +
>  src/rpm.ml              |  1 +
>  src/supermin.ml         |  4 +++-
>  6 files changed, 26 insertions(+), 1 deletion(-)
> 
> diff --git a/src/dpkg.ml b/src/dpkg.ml
> index 1bb3f7f..ed899cf 100644
> --- a/src/dpkg.ml
> +++ b/src/dpkg.ml
> @@ -191,6 +191,7 @@ let () =
>    let ph = {
>      ph_detect = dpkg_detect;
>      ph_init = dpkg_init;
> +    ph_fini = PHNoFini;
>      ph_package_of_string = dpkg_package_of_string;
>      ph_package_to_string = dpkg_package_to_string;
>      ph_package_name = dpkg_package_name;
> diff --git a/src/package_handler.ml b/src/package_handler.ml
> index b1dffc0..74d68f4 100644
> --- a/src/package_handler.ml
> +++ b/src/package_handler.ml
> @@ -59,6 +59,7 @@ let file_source file =
>  type package_handler = {
>    ph_detect : unit -> bool;
>    ph_init : settings -> unit;
> +  ph_fini : ph_fini;
>    ph_package_of_string : string -> package option;
>    ph_package_to_string : package -> string;
>    ph_package_name : package -> string;
> @@ -76,6 +77,9 @@ and ph_get_files =
>  and ph_download_package =
>  | PHDownloadPackage of (package -> string -> unit)
>  | PHDownloadAllPackages of (PackageSet.t -> string -> unit)
> +and ph_fini =
> +| PHNoFini
> +| PHFini of (unit -> unit)

This is unnecessary, since you can write the default (no handler) as:

  ph_fini = fun () -> ()

and thus avoid all the other special cases below.

ACK to the patch, but please remove the ph_fini type before committing.

Rich.

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