grub: Add an optional efiBootloaderId setting.

If the efiBootloaderId is set, it is used as the --bootloader-id when
installing grub-efi. The rationale is pretty much the same as for the
Gummiboot case.

If the setting is not used, the --bootloader-id is determined from the
branding's bootloaderEntryName (as before).

src/modules/grub/grub.conf

@@ -4,3 +4,8 @@
 grubInstall: "grub-install"
 grubMkconfig: "grub-mkconfig"
 grubCfg: "/boot/grub/grub.cfg"
+# Optionally set the --bootloader-id to use for EFI. If not set, this defaults
+# to the bootloaderEntryName from branding.desc with problematic characters
+# replaced. If an efiBootloaderId is specified here, it is taken to already be a
+# valid directory name, so no such postprocessing is done in this case.
+# efiBootloaderId: "dirname"

src/modules/grub/main.py

@@ -26,10 +26,14 @@ from libcalamares.utils import check_chroot_call
 def install_grub(boot_loader, fw_type):
     if fw_type == 'efi':
         efi_directory = "/boot/efi"
+        if "efiBootloaderId" in libcalamares.job.configuration:
+            efi_bootloader_id = libcalamares.job.configuration["efiBootloaderId"]
+        else:
             branding = libcalamares.globalstorage.value("branding")
             distribution = branding["bootloaderEntryName"]
             file_name_sanitizer = str.maketrans(" /", "_-")
-        check_chroot_call([libcalamares.job.configuration["grubInstall"], "--target=x86_64-efi", "--efi-directory={!s}".format(efi_directory), "--bootloader-id={!s}".format(distribution.translate(file_name_sanitizer))])
+            efi_bootloader_id = distribution.translate(file_name_sanitizer)
+        check_chroot_call([libcalamares.job.configuration["grubInstall"], "--target=x86_64-efi", "--efi-directory={!s}".format(efi_directory), "--bootloader-id={!s}".format(efi_bootloader_id)])
     else:
         install_path = boot_loader["installPath"]
         check_chroot_call([libcalamares.job.configuration["grubInstall"], install_path])