bug#40493: installer: Provide a way to select multiple keyboard layouts

["pelzflorian (Florian Pelz)" <pelzflorian@pelzflorian.de>]

[-- Attachment #1: Type: text/plain, Size: 725 bytes --]

On Tue, Apr 07, 2020 at 10:38:16PM +0200, Ludovic Courtès wrote:
> I think the approach is OK, even as-is.  We can then improve it by
> (hopefully) replacing the hard-coded list of non-Latin layouts (ar, jp,
> etc.) with code that determines whether the main layout is Latin or not.
>

I am still doing final testing, but I believe I can push the attached
patch.


> > +    (match first-layout
> > +      (("ar" "azerty") (list "ar,fr" "azerty," "grp:alt_shift_toggle"))
>                                                ^
> Remove comma?

The comma is needed, for example the Japanese Kana ("jp" "kana")
layout breaks otherwise.  I believe the reason is that the "kana"
variant gets applied to "us" layout.

Regards,
Florian

[-- Attachment #2: 0001-installer-Allow-Alt-Shift-toggle-from-non-Latin-keyb.patch --]
[-- Type: text/plain, Size: 12075 bytes --]

From 68fc18d2816e3997f38d0a3c69566d85b26c8719 Mon Sep 17 00:00:00 2001
From: Florian Pelz <pelzflorian@pelzflorian.de>
Date: Wed, 8 Apr 2020 11:46:16 +0200
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Subject: [PATCH] installer: Allow Alt+Shift toggle from non-Latin keyboard
 layouts.

Fixes <https://bugs.gnu.org/40493>.

* gnu/installer/newt/keymap.scm (%non-latin-layouts): New variable.
(toggleable-latin-layout): New procedure to compute combined layouts.
(run-keymap-page): Use it.
(keyboard-layout->configuration): Apply it in config.scm.
* gnu/installer/newt/help.scm (run-help-page): Mention Alt+Shift.
* gnu/installer/keymap.scm (kmscon-update-keymap): Pass on XKB options.
* gnu/installer/record.scm (<installer>): Adjust code comments.
* gnu/installer.scm (apply-keymap): Pass on XKB options.
(installer-steps): Adjust code comments.
* gnu/packages/patches/kmscon-runtime-keymap-switch.patch: Apply XKB options.
---
 gnu/installer.scm                             | 14 ++++---
 gnu/installer/keymap.scm                      |  8 +++-
 gnu/installer/newt/help.scm                   |  5 ++-
 gnu/installer/newt/keymap.scm                 | 40 ++++++++++++++++---
 gnu/installer/record.scm                      |  3 +-
 .../kmscon-runtime-keymap-switch.patch        | 27 ++++---------
 6 files changed, 63 insertions(+), 34 deletions(-)

diff --git a/gnu/installer.scm b/gnu/installer.scm
index 75c5a01570..72b7d195fd 100644
--- a/gnu/installer.scm
+++ b/gnu/installer.scm
@@ -2,6 +2,7 @@
 ;;; Copyright © 2018, 2020 Mathieu Othacehe <m.othacehe@gmail.com>
 ;;; Copyright © 2019, 2020 Ludovic Courtès <ludo@gnu.org>
 ;;; Copyright © 2019, 2020 Tobias Geerinckx-Rice <me@tobias.gr>
+;;; Copyright © 2020 Florian Pelz <pelzflorian@pelzflorian.de>
 ;;;
 ;;; This file is part of GNU Guix.
 ;;;
@@ -170,9 +171,9 @@ been performed at build time."
 (define apply-keymap
   ;; Apply the specified keymap. Use the default keyboard model.
   #~(match-lambda
-      ((layout variant)
+      ((layout variant options)
        (kmscon-update-keymap (default-keyboard-model)
-                             layout variant))))
+                             layout variant options))))
 
 (define* (compute-keymap-step context)
   "Return a gexp that runs the keymap-page of INSTALLER and install the
@@ -235,12 +236,13 @@ selected keymap."
 
          ;; The installer runs in a kmscon virtual terminal where loadkeys
          ;; won't work. kmscon uses libxkbcommon as a backend for keyboard
-         ;; input. It is possible to update kmscon current keymap by sending it
-         ;; a keyboard model, layout and variant, in a somehow similar way as
-         ;; what is done with setxkbmap utility.
+         ;; input. It is possible to update kmscon current keymap by sending
+         ;; it a keyboard model, layout, variant and options, in a somehow
+         ;; similar way as what is done with setxkbmap utility.
          ;;
          ;; So ask for a keyboard model, layout and variant to update the
-         ;; current kmscon keymap.
+         ;; current kmscon keymap.  For non-Latin layouts, we add an
+         ;; appropriate second layout and toggle via Alt+Shift.
          (installer-step
           (id 'keymap)
           (description (G_ "Keyboard mapping selection"))
diff --git a/gnu/installer/keymap.scm b/gnu/installer/keymap.scm
index df9fc5e441..d520b782fd 100644
--- a/gnu/installer/keymap.scm
+++ b/gnu/installer/keymap.scm
@@ -1,5 +1,6 @@
 ;;; GNU Guix --- Functional package management for GNU
 ;;; Copyright © 2018 Mathieu Othacehe <m.othacehe@gmail.com>
+;;; Copyright © 2020 Florian Pelz <pelzflorian@pelzflorian.de>
 ;;;
 ;;; This file is part of GNU Guix.
 ;;;
@@ -154,8 +155,8 @@ Configuration Database, describing possible XKB configurations."
       ((models layouts)
        (values models layouts)))))
 
-(define (kmscon-update-keymap model layout variant)
-  "Update kmscon keymap with the provided MODEL, LAYOUT and VARIANT."
+(define (kmscon-update-keymap model layout variant options)
+  "Update kmscon keymap with the provided MODEL, LAYOUT, VARIANT and OPTIONS."
   (and=>
    (getenv "KEYMAP_UPDATE")
    (lambda (keymap-file)
@@ -175,4 +176,7 @@ Configuration Database, describing possible XKB configurations."
          (put-u8 port 0)
 
          (format port variant)
+         (put-u8 port 0)
+
+         (format port options)
          (put-u8 port 0))))))
diff --git a/gnu/installer/newt/help.scm b/gnu/installer/newt/help.scm
index a488f5fa2a..3ccfaf2e54 100644
--- a/gnu/installer/newt/help.scm
+++ b/gnu/installer/newt/help.scm
@@ -1,5 +1,6 @@
 ;;; GNU Guix --- Functional package management for GNU
 ;;; Copyright © 2020 Mathieu Othacehe <m.othacehe@gmail.com>
+;;; Copyright © 2020 Florian Pelz <pelzflorian@pelzflorian.de>
 ;;;
 ;;; This file is part of GNU Guix.
 ;;;
@@ -31,7 +32,9 @@
            (cons (G_ "Change keyboard layout") keyboard-layout-selection)))
          (result
           (run-listbox-selection-page
-           #:info-text (G_ "This is the help menu, please choose an action.")
+           #:info-text (G_ "This is the help menu.  Here you can change your
+keyboard layout.  Non-Latin layouts can also be toggled with Alt+Shift.
+Please choose an action.")
            #:title (G_ "Installation help")
            #:listbox-items items
            #:listbox-item->text car
diff --git a/gnu/installer/newt/keymap.scm b/gnu/installer/newt/keymap.scm
index 0147a0b9d5..475ffc2261 100644
--- a/gnu/installer/newt/keymap.scm
+++ b/gnu/installer/newt/keymap.scm
@@ -1,6 +1,7 @@
 ;;; GNU Guix --- Functional package management for GNU
 ;;; Copyright © 2018, 2020 Mathieu Othacehe <m.othacehe@gmail.com>
 ;;; Copyright © 2019 Ludovic Courtès <ludo@gnu.org>
+;;; Copyright © 2020 Florian Pelz <pelzflorian@pelzflorian.de>
 ;;;
 ;;; This file is part of GNU Guix.
 ;;;
@@ -112,10 +113,35 @@ You can switch to different layout at any time from the help menu.")))
          variants))
     (cut append <> <>)))
 
+(define %non-latin-layouts
+  ;; List of keyboard layouts marked as $nonlatin in xkeyboard-config.
+  '("am" "ara" "ben" "bd" "bg" "bt" "by" "cs" "deva" "ge" "gh"
+    "gr" "guj" "guru" "il" "in" "ir" "iku" "jp" "kan" "kh" "kr"
+    "la" "lao" "lk" "mk" "mm" "mn" "mv" "mal" "olck" "ori" "pk"
+    "ru" "scc" "sy" "syr" "tel" "th" "tj" "tam" "ua" "uz"
+    ;; The list from xkeyboard-config is incomplete.  Add more layouts when
+    ;; noticed:
+    "et"))
+
+(define (toggleable-latin-layout layout variant)
+  "If LAYOUT is a non-Latin layout, return a new combined layout,
+a variant, and options that allow the user to switch between the
+non-Latin and the Latin layout.  Otherwise, return LAYOUT, VARIANT,
+and the empty string."
+  (if (member layout %non-latin-layouts)
+      (let ((latin-layout (if (string=? variant "azerty") "fr" "us")))
+        (list
+         (string-append layout "," latin-layout)
+         (string-append variant ",") ;comma to use variant only for non-Latin
+         "grp:alt_shift_toggle"))
+      (list layout variant "")))
+
 (define* (run-keymap-page layouts #:key (context #f))
   "Run a page asking the user to select a keyboard layout and variant. LAYOUTS
-is a list of supported X11-KEYMAP-LAYOUT. Return a list of two elements, the
-names of the selected keyboard layout and variant."
+is a list of supported X11-KEYMAP-LAYOUT.  For non-Latin keyboard layouts, a
+second layout and toggle options will be added automatically.  Return a list
+of three elements, the names of the selected keyboard layout, variant and
+options."
   (define keymap-steps
     (list
      (installer-step
@@ -151,14 +177,18 @@ names of the selected keyboard layout and variant."
                           (lambda (variant)
                             (gettext (x11-keymap-variant-name variant)
                                      "xkeyboard-config")))))
-      (list layout (or variant ""))))
+      (apply toggleable-latin-layout
+             (list layout (or variant "")))))
   (format-result
    (run-installer-steps #:steps keymap-steps)))
 
 (define (keyboard-layout->configuration keymap)
   "Return the operating system configuration snippet to install KEYMAP."
   (match keymap
-    ((name "")
+    ((name "" "")
      `((keyboard-layout (keyboard-layout ,name))))
-    ((name variant)
+    ((name variant "grp:alt_shift_toggle")
+     `((keyboard-layout (keyboard-layout ,name ,variant
+                                         #:options '("grp:alt_shift_toggle")))))
+    ((name variant _)
      `((keyboard-layout (keyboard-layout ,name ,variant))))))
diff --git a/gnu/installer/record.scm b/gnu/installer/record.scm
index 78acf50c63..13acd33fc6 100644
--- a/gnu/installer/record.scm
+++ b/gnu/installer/record.scm
@@ -1,5 +1,6 @@
 ;;; GNU Guix --- Functional package management for GNU
 ;;; Copyright © 2018, 2020 Mathieu Othacehe <m.othacehe@gmail.com>
+;;; Copyright © 2020 Florian Pelz <pelzflorian@pelzflorian.de>
 ;;;
 ;;; This file is part of GNU Guix.
 ;;;
@@ -63,7 +64,7 @@
   (exit-error installer-exit-error)
   ;; procedure void -> void
   (final-page installer-final-page)
-  ;; procedure (layouts context) -> (list layout variant)
+  ;; procedure (layouts context) -> (list layout variant options)
   (keymap-page installer-keymap-page)
   ;; procedure: (#:key supported-locales iso639-languages iso3166-territories)
   ;; -> glibc-locale
diff --git a/gnu/packages/patches/kmscon-runtime-keymap-switch.patch b/gnu/packages/patches/kmscon-runtime-keymap-switch.patch
index 656c76fa40..deb5688daf 100644
--- a/gnu/packages/patches/kmscon-runtime-keymap-switch.patch
+++ b/gnu/packages/patches/kmscon-runtime-keymap-switch.patch
@@ -1,14 +1,5 @@
-From 360d44d67e7be46108bec982ff2e79b89f04a9a3 Mon Sep 17 00:00:00 2001
-From: Mathieu Othacehe <m.othacehe@gmail.com>
-Date: Thu, 15 Nov 2018 14:34:40 +0900
-Subject: [PATCH] add runtime keymap switch support.
-
----
- src/pty.c                  | 23 ++++++++++-
- src/uterm_input.c          |  2 +
- src/uterm_input_internal.h |  5 +++
- src/uterm_input_uxkb.c     | 83 ++++++++++++++++++++++++++++++++++++++
- 4 files changed, 111 insertions(+), 2 deletions(-)
+By Mathieu Othacehe <m.othacehe@gmail.com>.
+Modified by Florian Pelz <pelzflorian@pelzflorian.de>.
 
 diff --git a/src/pty.c b/src/pty.c
 index 1443f4a..f64cb5b 100644
@@ -124,7 +115,7 @@ index 04e6cc9..ec44459 100644
  		     uint16_t key_state,
  		     uint16_t code);
 diff --git a/src/uterm_input_uxkb.c b/src/uterm_input_uxkb.c
-index 925c755..4760972 100644
+index 925c755..5d5c22e 100644
 --- a/src/uterm_input_uxkb.c
 +++ b/src/uterm_input_uxkb.c
 @@ -31,6 +31,9 @@
@@ -137,7 +128,7 @@ index 925c755..4760972 100644
  #include <xkbcommon/xkbcommon.h>
  #include "shl_hook.h"
  #include "shl_llog.h"
-@@ -178,6 +181,86 @@ static void timer_event(struct ev_timer *timer, uint64_t num, void *data)
+@@ -178,6 +181,87 @@ static void timer_event(struct ev_timer *timer, uint64_t num, void *data)
  	shl_hook_call(dev->input->hook, dev->input, &dev->repeat_event);
  }
  
@@ -145,11 +136,11 @@ index 925c755..4760972 100644
 +{
 +	struct uterm_input_dev *dev = data;
 +	char in;
-+	char keymap[3][255];
++	char keymap[4][255];
 +	int pos = 0;
 +	int curr_keymap = 0;
 +	int ret;
-+	char *model, *layout, *variant;
++	char *model, *layout, *variant, *options;
 +
 +	if (!(mask & EV_READABLE))
 +		return;
@@ -159,6 +150,7 @@ index 925c755..4760972 100644
 +	model = keymap[0];
 +	layout = keymap[1];
 +	variant = keymap[2];
++	options = keymap[3];
 +
 +	do {
 +	  ret = read(dev->rupdate_fd, &in, sizeof(in));
@@ -175,7 +167,7 @@ index 925c755..4760972 100644
 +
 +	llog_info(dev->input, "HANDLER CALLED %s|%s|%s\n",
 +		  model, layout, variant);
-+	uxkb_desc_init(dev->input, model, layout, variant, NULL, NULL);
++	uxkb_desc_init(dev->input, model, layout, variant, options, NULL);
 +
 +	dev->state = xkb_state_new(dev->input->keymap);
 +	if (!dev->state) {
@@ -224,6 +216,3 @@ index 925c755..4760972 100644
  int uxkb_dev_init(struct uterm_input_dev *dev)
  {
  	int ret;
--- 
-2.17.1
-
-- 
2.26.0