installer: Implement a dialog on /var/guix/installer-socket.

This will allow us to automate testing of the installer.

* gnu/installer/utils.scm (%client-socket-file)
(current-server-socket, current-clients): New variables.
(open-server-socket, call-with-server-socket): New procedure.
(with-server-socket): New macro.
(run-shell-command): Add call to 'send-to-clients'.  Select on both
current-input-port and current-clients.
* gnu/installer/steps.scm (run-installer-steps): Wrap 'call-with-prompt'
in 'with-socket-server'.  Call 'sigaction' for SIGPIPE.
* gnu/installer/newt/page.scm (watch-clients!, close-port-and-reuse-fd)
(run-form-with-clients, send-to-clients): New procedures.
(draw-info-page): Add call to 'run-form-with-clients'.
(run-input-page): Likewise.  Handle EXIT-REASON equal to 'exit-fd-ready.
(run-confirmation-page): Likewise.
(run-listbox-selection-page): Likewise.  Define 'choice->item' and use it.
(run-checkbox-tree-page): Likewise.
(run-file-textbox-page): Add call to 'run-form-with-clients'.  Handle
'exit-fd-ready'.
* gnu/installer/newt/partition.scm (run-disk-page): Pass
 #:client-callback-procedure to 'run-listbox-selection-page'.
* gnu/installer/newt/user.scm (run-user-page): Call
'run-form-with-clients'.  Handle 'exit-fd-ready'.
* gnu/installer/newt/welcome.scm (run-menu-page): Define
'choice->item' and use it.  Call 'run-form-with-clients'.
* gnu/installer/newt/final.scm (run-install-success-page)
(run-install-failed-page): When (current-clients) is non-empty, call
'send-to-clients' without displaying a choice window.

1 files changed, 7 insertions, 1 deletions

diff --git a/gnu/installer/newt/partition.scm b/gnu/installer/newt/partition.scm
index 3cba7f77dd..c925e410a9 100644
--- a/gnu/installer/newt/partition.scm
+++ b/gnu/installer/newt/partition.scm
@@ -1,6 +1,6 @@
 ;;; GNU Guix --- Functional package management for GNU
 ;;; Copyright © 2018, 2019 Mathieu Othacehe <m.othacehe@gmail.com>
-;;; Copyright © 2019 Ludovic Courtès <ludo@gnu.org>
+;;; Copyright © 2019, 2020 Ludovic Courtès <ludo@gnu.org>
 ;;; Copyright © 2020 Tobias Geerinckx-Rice <me@tobias.gr>
 ;;;
 ;;; This file is part of GNU Guix.
@@ -682,6 +682,12 @@ by pressing the Exit button.~%~%")))
           #:allow-delete? #t
           #:button-text (G_ "OK")
           #:button-callback-procedure button-ok-action
+
+          ;; Consider client replies equivalent to hitting the "OK" button.
+          ;; XXX: In practice this means that clients cannot do anything but
+          ;; approve the predefined list of partitions.
+          #:client-callback-procedure (lambda (_) (button-ok-action))
+
           #:button2-text (G_ "Exit")
           #:button2-callback-procedure button-exit-action
           #:listbox-callback-procedure listbox-action