[bug#37039] [PATCH] machine: Use 'become-command'.

[Christopher Lemmer Webber <cwebber@dustycloud.org>]

Looks fine and simple.  Merged and pushed.

Jakob L. Kreuze writes:

> * gnu/machine/ssh.scm (managed-host-remote-eval): Pass an appropriate
> 'become-command' to 'remote-eval'.
> * guix/ssh.scm (remote-authorize-signing-key): Add optional
> 'become-command' argument.
> All callers changed.
> ---
>  gnu/machine/ssh.scm | 7 +++++--
>  guix/ssh.scm        | 5 +++--
>  2 files changed, 8 insertions(+), 4 deletions(-)
>
> diff --git a/gnu/machine/ssh.scm b/gnu/machine/ssh.scm
> index ac3aa3e370..aafe0ccf41 100644
> --- a/gnu/machine/ssh.scm
> +++ b/gnu/machine/ssh.scm
> @@ -126,7 +126,9 @@ an environment type of 'managed-host."
>                   #:build-locally?
>                   (machine-ssh-configuration-build-locally? config)
>                   #:system
> -                 (machine-ssh-configuration-system config))))
> +                 (machine-ssh-configuration-system config)
> +                 #:become-command
> +                 (machine-become-command machine))))
>  
>  \f
>  ;;;
> @@ -377,7 +379,8 @@ have you run 'guix archive --generate-key?'")
>                                      (lambda (port)
>                                        (string->canonical-sexp
>                                         (get-string-all port))))
> -                                  (machine-ssh-session machine)))
> +                                  (machine-ssh-session machine)
> +                                  (machine-become-command machine)))
>    (mlet %store-monad ((_ (check-deployment-sanity machine))
>                        (boot-parameters (machine-boot-parameters machine)))
>      (let* ((os (machine-operating-system machine))
> diff --git a/guix/ssh.scm b/guix/ssh.scm
> index 24834c6f68..7bc499a2fe 100644
> --- a/guix/ssh.scm
> +++ b/guix/ssh.scm
> @@ -302,7 +302,7 @@ the machine on the other end of SESSION."
>    (inferior-remote-eval '(begin (use-modules (guix utils)) (%current-system))
>                          session))
>  
> -(define (remote-authorize-signing-key key session)
> +(define* (remote-authorize-signing-key key session #:optional become-command)
>    "Send KEY, a canonical sexp containing a public key, over SESSION and add it
>  to the system ACL file if it has not yet been authorized."
>    (inferior-remote-eval
> @@ -321,7 +321,8 @@ to the system ACL file if it has not yet been authorized."
>            (mkdir-p (dirname %acl-file))
>            (with-atomic-file-output %acl-file
>              (cut write-acl acl <>)))))
> -   session))
> +   session
> +   become-command))
>  
>  (define* (send-files local files remote
>                       #:key