From 95f286b9b474fc71889bfeb0c31f5ca07b8ff245 Mon Sep 17 00:00:00 2001
From: Simon de Vlieger <cmdr@supakeen.com>
Date: Mon, 3 Aug 2026 18:12:06 +0200
Subject: [PATCH] kernel-config: entry_name_format in install.conf

Extend load_kernel_install_conf_at() to parse the new entry_name_format=
setting from install.conf. This plumbing only, no behavioral change yet.
Existing callers pass NULL for the new parameter.

The entry_name_format= setting will allow configuring the boot entry
filename format using specifiers, replacing the current hardcoded
$ENTRY_TOKEN-$KERNEL_VERSION pattern. This is useful for image-based OS
builds (e.g. via mkosi, or image-builder) that require versioned UKI
filenames in the ESP for sysupdate A/B updates.

Having this configuration option allows to do that directly at build
time without having to side-step kernel-install and moving files around
manually.
---
 src/bootctl/bootctl-install.c       |  3 ++-
 src/kernel-install/kernel-install.c |  3 ++-
 src/shared/kernel-config.c          | 19 ++++++++++++-------
 src/shared/kernel-config.h          |  8 +++++---
 4 files changed, 21 insertions(+), 12 deletions(-)

diff --git a/src/bootctl/bootctl-install.c b/src/bootctl/bootctl-install.c
index 1610d11e920..080900c1f57 100644
--- a/src/bootctl/bootctl-install.c
+++ b/src/bootctl/bootctl-install.c
@@ -338,7 +338,8 @@ static int load_kernel_install_layout(InstallContext *c) {
                         /* ret_boot_root= */ NULL,
                         &layout,
                         /* ret_initrd_generator= */ NULL,
-                        /* ret_uki_generator= */ NULL);
+                        /* ret_uki_generator= */ NULL,
+                        /* ret_entry_name_format= */ NULL);
         if (r <= 0)
                 return r;
 
diff --git a/src/kernel-install/kernel-install.c b/src/kernel-install/kernel-install.c
index 69fdbcfc34a..8f5be2b42b4 100644
--- a/src/kernel-install/kernel-install.c
+++ b/src/kernel-install/kernel-install.c
@@ -467,7 +467,8 @@ static int context_load_install_conf(Context *c) {
                         &boot_root,
                         &layout,
                         &initrd_generator,
-                        &uki_generator);
+                        &uki_generator,
+                        /* ret_entry_name_format= */ NULL);
         if (r <= 0)
                 return r;
 
diff --git a/src/shared/kernel-config.c b/src/shared/kernel-config.c
index 3f575439a78..d12ad61d93e 100644
--- a/src/shared/kernel-config.c
+++ b/src/shared/kernel-config.c
@@ -14,16 +14,19 @@ int load_kernel_install_conf_at(
                 char **ret_boot_root,
                 char **ret_layout,
                 char **ret_initrd_generator,
-                char **ret_uki_generator) {
+                char **ret_uki_generator,
+                char **ret_entry_name_format) {
 
         _cleanup_free_ char *machine_id = NULL, *boot_root = NULL, *layout = NULL,
-                            *initrd_generator = NULL, *uki_generator = NULL;
+                            *initrd_generator = NULL, *uki_generator = NULL,
+                            *entry_name_format = NULL;
         const ConfigTableItem items[] = {
-                { NULL, "MACHINE_ID",       config_parse_string, 0, &machine_id       },
-                { NULL, "BOOT_ROOT",        config_parse_string, 0, &boot_root        },
-                { NULL, "layout",           config_parse_string, 0, &layout           },
-                { NULL, "initrd_generator", config_parse_string, 0, &initrd_generator },
-                { NULL, "uki_generator",    config_parse_string, 0, &uki_generator    },
+                { NULL, "MACHINE_ID",        config_parse_string, 0, &machine_id        },
+                { NULL, "BOOT_ROOT",         config_parse_string, 0, &boot_root         },
+                { NULL, "layout",            config_parse_string, 0, &layout            },
+                { NULL, "initrd_generator",  config_parse_string, 0, &initrd_generator  },
+                { NULL, "uki_generator",     config_parse_string, 0, &uki_generator     },
+                { NULL, "entry_name_format", config_parse_string, 0, &entry_name_format },
                 {}
         };
         int r;
@@ -71,5 +74,7 @@ int load_kernel_install_conf_at(
                 *ret_initrd_generator = TAKE_PTR(initrd_generator);
         if (ret_uki_generator)
                 *ret_uki_generator = TAKE_PTR(uki_generator);
+        if (ret_entry_name_format)
+                *ret_entry_name_format = TAKE_PTR(entry_name_format);
         return r >= 0;  /* Return 0 if we got -ENOENT above, 1 otherwise. */
 }
diff --git a/src/shared/kernel-config.h b/src/shared/kernel-config.h
index d46aba82785..34c71387b9b 100644
--- a/src/shared/kernel-config.h
+++ b/src/shared/kernel-config.h
@@ -12,7 +12,8 @@ int load_kernel_install_conf_at(
                 char **ret_boot_root,
                 char **ret_layout,
                 char **ret_initrd_generator,
-                char **ret_uki_generator);
+                char **ret_uki_generator,
+                char **ret_entry_name_format);
 
 static inline int load_kernel_install_conf(
                 const char *root,
@@ -21,7 +22,8 @@ static inline int load_kernel_install_conf(
                 char **ret_boot_root,
                 char **ret_layout,
                 char **ret_initrd_generator,
-                char **ret_uki_generator) {
+                char **ret_uki_generator,
+                char **ret_entry_name_format) {
 
-        return load_kernel_install_conf_at(root, XAT_FDROOT, conf_root, ret_machine_id, ret_boot_root, ret_layout, ret_initrd_generator, ret_uki_generator);
+        return load_kernel_install_conf_at(root, XAT_FDROOT, conf_root, ret_machine_id, ret_boot_root, ret_layout, ret_initrd_generator, ret_uki_generator, ret_entry_name_format);
 }