[Buildroot] [PATCH v4 1/1] package/mender-grubenv: fix grub module checks

[Adam Duskett]

Commit 3efb5e31fc05705ce3c46b1f0ec031978a5cfab6 broke mender-grubenv by
splititng up BR2_TARGET_GRUB2_BUILTIN_MODULES and
BR2_TARGET_GRUB2_BUILTIN_MODULES_EFI. Indeed, when a user now builds a system
with EFI, the MENDER_GRUBENV_MODULES_MISSING list always returns a full list
of grub modules, resulting in the error condition on line 46 to trigger.

In addition, BR2_TARGET_GRUB2_BUILTIN_MODULES has been renamed to
BR2_TARGET_GRUB2_BUILTIN_MODULES_PC, so this is changed in mender-grubenv.mk
as well.

- Add a ifneq check for both efi and i386 targets. If any of them are selected,
  check if the corresponding module list is empty and print an error message if
  so.

- Add two ifeqs, one for BR2_TARGET_GRUB2_BUILTIN_MODULES_EFI and the other
  for BR2_TARGET_GRUB2_BUILTIN_MODULES_PC. If either is not empty,
  check for the required modules and error out if either of the two
  have missing modules.

- Split up the MENDER_GRUBENV_INSTALL_IMAGES_CMDS into two separate parts, one
  for I386_PC/ARM_UBOOT, and another for EFI targets. This allows both EFI and
  I386 builds to install at the same time.

Signed-off-by: Adam Duskett <aduskett at gmail.com>
---
changes v1 -> v2:
  - Change ifeq ($(BR2_TARGET_GRUB2_X86_64_EFI),y) to
    ifneq ($(BR2_TARGET_GRUB2_BUILTIN_MODULES_EFI),) to cover all grub2 efi
    scenarios. (Thomas)
  
  - Change BR2_TARGET_GRUB2_BUILTIN_MODULES to
    BR2_TARGET_GRUB2_BUILTIN_MODULES_PC (thomas)

Changes v2 -> v3:
  - Check for both MODULES_EFI and MODULES_PC (Thomas)

Changes v3 -> v4:
  - Add qstrips to needed variables (Thomas)
  - Check for empty module lists (Thomas)
  - Split up MENDER_GRUBENV_INSTALL_IMAGES_CMDS to work with pc and efi at the
    same time.

 package/mender-grubenv/mender-grubenv.mk | 52 ++++++++++++++++++------
 1 file changed, 40 insertions(+), 12 deletions(-)

diff --git a/package/mender-grubenv/mender-grubenv.mk b/package/mender-grubenv/mender-grubenv.mk
index 07df25512c..bb4ec87755 100644
--- a/package/mender-grubenv/mender-grubenv.mk
+++ b/package/mender-grubenv/mender-grubenv.mk
@@ -31,14 +31,38 @@ MENDER_GRUBENV_DEFINES = \
 # These grub modules must be built in for the grub scripts to work properly.
 # Without them, the system will not boot.
 MENDER_GRUBENV_MANDATORY_MODULES=loadenv hashsum echo halt gcry_sha256 test regexp
-MENDER_GRUBENV_MODULES_MISSING = \
-	$(filter-out $(call qstrip,$(BR2_TARGET_GRUB2_BUILTIN_MODULES)),\
+
+# Unfortuantly, there is no easy way to check if the efi list is empty without
+# checking to see if any of the supported EFI platforms are selected.
+ifneq ($(BR2_TARGET_GRUB2_I386_EFI)$(BR2_TARGET_GRUB2_X86_64_EFI)$(BR2_TARGET_GRUB2_ARM_EFI)$(BR2_TARGET_GRUB2_ARM64_EFI),)
+ifeq ($(call qstrip,$(BR2_TARGET_GRUB2_BUILTIN_MODULES_EFI)),)
+$(error The following missing grub2 efi modules must be enabled for mender-grubenv \
+	to work: $(MENDER_GRUBENV_MANDATORY_MODULES))
+endif
+MENDER_GRUBENV_MODULES_MISSING_EFI = \
+	$(filter-out $(call qstrip,$(BR2_TARGET_GRUB2_BUILTIN_MODULES_EFI)),\
+		$(MENDER_GRUBENV_MANDATORY_MODULES))
+endif
+
+ifeq ($(BR2_TARGET_GRUB2_I386_PC),y)
+ifeq ($(call qstrip,$(BR2_TARGET_GRUB2_BUILTIN_MODULES_PC)),)
+$(error The following missing grub2 efi modules must be enabled for mender-grubenv \
+	to work: $(MENDER_GRUBENV_MANDATORY_MODULES))
+endif
+MENDER_GRUBENV_MODULES_MISSING_PC = \
+	$(filter-out $(call qstrip,$(BR2_TARGET_GRUB2_BUILTIN_MODULES_PC)),\
 		$(MENDER_GRUBENV_MANDATORY_MODULES))
+endif
 
 ifeq ($(BR2_PACKAGE_MENDER_GRUBENV)$(BR_BUILDING),yy)
-ifneq ($(MENDER_GRUBENV_MODULES_MISSING),)
-$(error The following missing grub2 modules must be enabled for mender-grubenv \
-	to work: $(MENDER_GRUBENV_MODULES_MISSING))
+ifneq ($(MENDER_GRUBENV_MODULES_MISSING_EFI),)
+$(error The following missing grub2 efi modules must be enabled for mender-grubenv \
+	to work: $(MENDER_GRUBENV_MODULES_MISSING_EFI))
+endif
+
+ifneq ($(MENDER_GRUBENV_MODULES_MISSING_PC),)
+$(error The following missing grub2 pc modules must be enabled for mender-grubenv \
+	to work: $(MENDER_GRUBENV_MODULES_MISSING_PC))
 endif
 endif
 
@@ -56,19 +80,23 @@ endef
 
 # Overwrite the default grub2 config files with the ones in this package.
 ifeq ($(BR2_TARGET_GRUB2_I386_PC)$(BR2_TARGET_GRUB2_ARM_UBOOT),y)
-define MENDER_GRUBENV_INSTALL_IMAGES_CMDS
-	mkdir -p $(BINARIES_DIR)/boot-part/grub
+define MENDER_GRUBENV_INSTALL_I386_CFG
+	mkdir -p $(BINARIES_DIR)/boot-part/grub;
 	cp -dpfr $(TARGET_DIR)/boot/grub/grub.cfg \
 		$(TARGET_DIR)/boot/grub/mender_grubenv* \
-		$(BINARIES_DIR)/boot-part/grub
+		$(BINARIES_DIR)/boot-part/grub;
 endef
-else
-define MENDER_GRUBENV_INSTALL_IMAGES_CMDS
-	mkdir -p $(BINARIES_DIR)/efi-part/EFI/BOOT
+MENDER_GRUBENV_INSTALL_IMAGES_CMDS += $(MENDER_GRUBENV_INSTALL_I386_CFG)
+endif
+
+ifneq ($(BR2_TARGET_GRUB2_I386_EFI)$(BR2_TARGET_GRUB2_X86_64_EFI)$(BR2_TARGET_GRUB2_ARM_EFI)$(BR2_TARGET_GRUB2_ARM64_EFI),)
+define MENDER_GRUBENV_INSTALL_EFI_CFG
+	mkdir -p $(BINARIES_DIR)/efi-part/EFI/BOOT;
 	cp -dpfr $(TARGET_DIR)/boot/EFI/BOOT/grub.cfg \
 		$(TARGET_DIR)/boot/EFI/BOOT/mender_grubenv* \
-		$(BINARIES_DIR)/efi-part/EFI/BOOT
+		$(BINARIES_DIR)/efi-part/EFI/BOOT;
 endef
+MENDER_GRUBENV_INSTALL_IMAGES_CMDS += $(MENDER_GRUBENV_INSTALL_EFI_CFG)
 endif
 
 $(eval $(generic-package))
-- 
2.33.1