contrib/: expand font setting capabilities

ZFSBootMenu binary releases use a default font size that's barely
suitable for 2k screens and entirely unsuitable for 4k screens. In an
attempt to fix this, a new script has been added that introduces
automatic console font resizing.

Utilizing the Terminus font, we can pick a range of bold font sizes to
better match screen resolutions. Working backwards from the largest to
the smallest, the hook simply runs `setfont` and then checks if COLUMNS
is at least 100 characters. If it is not, the next font is selected and
it tries again.

Based on documentation, Terminus fonts prefixed with a 'v' have all
mappings/codepages in them; so they should support the maximal number of
languages.

contrib/20-console-autosize.sh is included in all release and recovery
images. The automatic font setting behavior can be disabled via
zbm.autosize=(0|off).

contrib/console-init.sh has been renamed to ensure it precedes this
hook, since 10-console-init.sh calls console_init from Dracut, which is
hard-coded to set a console font. Since console_init also performs setting
a keymap, it should always be executed.

The legacy behavior of setting a font via rd.vconsole.font
overrides/disables zbm.autosize.

contrib/20-console-autosize.sh

@@ -0,0 +1,37 @@
+#!/bin/bash
+# vim: softtabstop=2 shiftwidth=2 expandtab
+
+## This early-setup hook attempts to get a physical (non-serial) console
+## to at least 100 columns. The Dracut module 'i18n' is required to populate
+## /usr/share/consolefonts and to add the 'setfont' binary.
+##
+## This hook is enabled by default in Release and Recovery builds. To disable,
+## add `zbm.autosize=off` to the ZFSBootMenu kernel commandline.
+## If rd.vconsole.font is defined, autosizing is skipped to not override
+## this font preference.
+
+
+#shellcheck disable=SC1091
+source /lib/zfsbootmenu-kcl.sh || exit 1
+source /lib/kmsg-log-lib.sh || exit 1
+
+if [ -z "${control_term}" ] && [ -f /etc/zfsbootmenu.conf ]; then
+  #shellcheck disable=SC1091
+  source /etc/zfsbootmenu.conf
+fi
+
+[ -c "${control_term}" ] || exit 1
+
+# Ensure that control_term is not a serial console
+tty_re='/dev/tty[0-9]'
+[[ ${control_term} =~ ${tty_re} ]] || exit 1
+
+if get_zbm_bool 1 zbm.autosize && ! font=$( get_zbm_arg rd.vconsole.font ) ; then
+  for font in ter-v32b ter-v28b ter-v24b ter-v20b ter-v14b ; do
+    setfont "${font}" >/dev/null 2>&1
+    if [ "${COLUMNS}" -ge 100 ]; then
+      zdebug "set font to ${font}, screen is ${COLUMNS}x${LINES}"
+      break
+    fi
+  done
+fi

etc/zfsbootmenu/release.conf.d/common.conf

@@ -1,5 +1,5 @@
 zfsbootmenu_teardown+=" /zbm/contrib/xhci-teardown.sh "
-zfsbootmenu_early_setup+=" /zbm/contrib/console-init.sh "
+zfsbootmenu_early_setup+=" /zbm/contrib/10-console-init.sh /zbm/contrib/20-console-autosize.sh "
 
 install_optional_items+=" /etc/zbm-commit-hash "
 

etc/zfsbootmenu/release.yaml

@@ -11,4 +11,4 @@ EFI:
   Versions: false
   Enabled: true
 Kernel:
-  CommandLine: zfsbootmenu loglevel=4 nomodeset
+  CommandLine: loglevel=4 nomodeset

testing/run.sh

@@ -234,6 +234,14 @@ fi
 if [ -n "${DISPLAY_TYPE}" ]; then
   # Use the indicated graphical display
   DISPLAY_ARGS=( "-display" "${DISPLAY_TYPE}" )
+
+  # Add release hooks, supported only under Dracut
+  if ((DRACUT)); then
+    cat <<-EOF >> "${TESTDIR}/dracut.conf.d/testing.conf"
+	zfsbootmenu_early_setup+=" $( realpath -e ../contrib )/10-console-init.sh "
+	zfsbootmenu_early_setup+=" $( realpath -e ../contrib )/20-console-autosize.sh "
+	EOF
+  fi
 else
   # Suppress graphical display (implies serial mode)
   DISPLAY_ARGS=( "-nographic" )