spec/posttrans: move grub config stub creation out of spec

Resolves: #RHEL-69944
Signed-off-by: Nicolas Frayer <nfrayer@redhat.com>

gen_grub_cfgstub

@@ -0,0 +1,29 @@
+#!/bin/sh
+set -eu
+
+if [ $# -ne 2 ]
+  then
+    echo "Missing argument"
+    echo "Usage: script.sh GRUB_HOME EFI_HOME"
+    exit 1
+fi
+
+GRUB_HOME=$1
+EFI_HOME=$2
+
+# create a stub grub2 config in EFI
+BOOT_UUID=$(grub2-probe --target=fs_uuid "${GRUB_HOME}")
+GRUB_DIR=$(grub2-mkrelpath "${GRUB_HOME}")
+
+echo "Generating grub stub config for drive " "${BOOT_UUID}"
+echo "GRUB_DIR=" "${GRUB_DIR}"
+echo "EFI_HOME=" "${EFI_HOME}"
+
+cat << EOF > "${EFI_HOME}"/grub.cfg.stb
+search --no-floppy --root-dev-only --fs-uuid --set=dev ${BOOT_UUID}
+set prefix=(\$dev)${GRUB_DIR}
+export \$prefix
+configfile \$prefix/grub.cfg
+EOF
+
+mv ${EFI_HOME}/grub.cfg.stb ${EFI_HOME}/grub.cfg

grub.macros

@@ -522,6 +522,8 @@ install -m 700 %{3} $RPM_BUILD_ROOT%{efi_esp_dir}/%{3}		\
 %ifarch %{arm}							\
 install -D -m 700 %{2} $RPM_BUILD_ROOT%{efi_esp_boot}/BOOTARM.EFI \
 %endif								\
+install -D -m 700 %{SOURCE13}                                  \\\
+    ${RPM_BUILD_ROOT}/usr/bin/gen_grub_cfgstub         		\
 install -D -m 700 unicode.pf2					\\\
 	${RPM_BUILD_ROOT}/boot/%{name}/fonts/unicode.pf2		\
 ${RPM_BUILD_ROOT}/%{_bindir}/%{name}-editenv			\\\
@@ -633,6 +635,7 @@ ln -s ../boot/%{name}/grub.cfg					\\\
 %attr(0700,root,root) %verify(not mtime) %{efi_esp_boot}/BOOTARM.EFI \
 %endif								\
 %attr(0700,root,root)/boot/%{name}/fonts			\
+%attr(0700,root,root)/usr/bin/gen_grub_cfgstub			\
 %dir %attr(0700,root,root)/boot/loader/entries			\
 %ghost %config(noreplace) %attr(0600,root,root)/boot/%{name}/grub.cfg	\
 %ghost %config(noreplace) %verify(not mtime) %attr(0700,root,root)%{efi_esp_dir}/grub.cfg	\

grub2.spec

@@ -16,7 +16,7 @@
 Name:		grub2
 Epoch:		1
 Version:	2.06
-Release:	110%{?dist}
+Release:	111%{?dist}
 Summary:	Bootloader with support for Linux, Multiboot and more
 License:	GPLv3+
 URL:		http://www.gnu.org/software/grub/
@@ -34,6 +34,7 @@ Source9:	strtoull_test.c
 Source10:	20-grub.install
 Source11:	grub.patches
 Source12:	sbat.csv.in
+Source13:	gen_grub_cfgstub
 
 %include %{SOURCE1}
 
@@ -361,23 +362,13 @@ if test -f ${EFI_HOME}/grub.cfg; then
 fi
 
 # create a stub grub2 config in EFI
-BOOT_UUID=$(%{name}-probe --target=fs_uuid ${GRUB_HOME})
+gen_grub_cfgstub $GRUB_HOME $EFI_HOME || :
-GRUB_DIR=$(%{name}-mkrelpath ${GRUB_HOME})
-
-cat << EOF > ${EFI_HOME}/grub.cfg.stb
-search --no-floppy --root-dev-only --fs-uuid --set=dev ${BOOT_UUID}
-set prefix=(\$dev)${GRUB_DIR}
-export \$prefix
-configfile \$prefix/grub.cfg
-EOF
 
 if test -f ${EFI_HOME}/grubenv; then
     cp -a ${EFI_HOME}/grubenv ${EFI_HOME}/grubenv.rpmsave
     mv --force ${EFI_HOME}/grubenv ${GRUB_HOME}/grubenv
 fi
 
-mv ${EFI_HOME}/grub.cfg.stb ${EFI_HOME}/grub.cfg
-
 %files common -f grub.lang
 %dir %{_libdir}/grub/
 %dir %{_datarootdir}/grub/
@@ -547,6 +538,10 @@ mv ${EFI_HOME}/grub.cfg.stb ${EFI_HOME}/grub.cfg
 %endif
 
 %changelog
+* Tue Jul 29 2025 Nicolas Frayer <nfrayer@redhat.com> 2.06-111
+- spec/posttrans: move grub config stub creation out of spec
+- Resolves: #RHEL-69944
+
 * Fri Jun 6 2025 Nicolas Frayer <nfrayer@redhat.com> - 2.06-110
 - osdep/linux/getroot: Detect DDF container similar to IMSM
 - Resolves: #RHEL-44336