From fbcc3889178a98d6189da5ef0ed1146613cce750 Mon Sep 17 00:00:00 2001
From: Pascal Hambourg <pascal@plouf.fr.eu.org>
Date: Mon, 24 Feb 2025 18:10:45 +0100
Subject: [PATCH] util/grub.d/30_os-prober.in: Conditionally show or hide chain
 and efi menu entries

On systems which support multiple boot platforms such as BIOS and
EFI, it makes no sense to show menu entries which are not supported
by the current boot platform. Menu entries generated from os-prober
"chain" boot type use boot sector chainloading which is supported
on PC BIOS platform only.

Show "chain" menu entries only if boot platform is PC BIOS.
Show "efi" menu entries only if boot platform is EFI.

This is aimed to allow os-prober to report both EFI and PC BIOS
boot loaders regardless of the current boot mode on x86 systems
which support both EFI and legacy BIOS boot, in order to generate
a config file which can be used with either BIOS or EFI boot.

Signed-off-by: Pascal Hambourg <pascal@plouf.fr.eu.org>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
---
 util/grub.d/30_os-prober.in | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/util/grub.d/30_os-prober.in b/util/grub.d/30_os-prober.in
index 394747759..5d8d75292 100644
--- a/util/grub.d/30_os-prober.in
+++ b/util/grub.d/30_os-prober.in
@@ -162,6 +162,8 @@ for OS in ${OSPROBED} ; do
 
 	  onstr="$(gettext_printf "(on %s)" "${DEVICE}")"
       cat << EOF
+# This menu entry is supported only on PC BIOS platforms.
+if [ "\$grub_platform" = "pc" ]; then
 menuentry '$(echo "${LONGNAME} $onstr" | grub_quote)' $CLASS --class os \$menuentry_id_option 'osprober-chain-$(grub_get_device_id "${DEVICE}")' {
 EOF
       save_default_entry | grub_add_tab
@@ -186,6 +188,7 @@ EOF
       cat <<EOF
 	chainloader +1
 }
+fi
 EOF
     ;;
     efi)
@@ -194,6 +197,8 @@ EOF
 	DEVICE=${DEVICE%@*}
 	onstr="$(gettext_printf "(on %s)" "${DEVICE}")"
       cat << EOF
+# This menu entry is supported only on EFI platforms.
+if [ "\$grub_platform" = "efi" ]; then
 menuentry '$(echo "${LONGNAME} $onstr" | grub_quote)' $CLASS --class os \$menuentry_id_option 'osprober-efi-$(grub_get_device_id "${DEVICE}")' {
 EOF
       save_default_entry | sed -e "s/^/\t/"
@@ -202,6 +207,7 @@ EOF
       cat <<EOF
 	chainloader ${EFIPATH}
 }
+fi
 EOF
     ;;
     linux)