tool(systemd-boot): install it once instead of checking for each generation

systemd-boot is now installed once for many generations rather than multiple times.

This means it is not really possible to manage different system in the same "machine", which is a very
obscure usecase, theoretically possible, but not yet encountered.

rust/tool/shared/src/esp.rs

@@ -53,7 +53,7 @@ impl Architecture {
 /// Generic ESP paths which can be specific to a bootloader
 pub trait EspPaths<const N: usize> {
     /// Build an ESP path structure out of the ESP root directory
-    fn new(esp: impl AsRef<Path>) -> Self;
+    fn new(esp: impl AsRef<Path>, arch: Architecture) -> Self;
 
     /// Return the used file paths to store as garbage collection roots.
     fn iter(&self) -> std::array::IntoIter<&PathBuf, N>;

rust/tool/systemd/src/install.rs

@@ -45,8 +45,8 @@ impl Installer {
         generation_links: Vec<PathBuf>,
     ) -> Self {
         let mut gc_roots = Roots::new();
-        let esp_paths = SystemdEspPaths::new(esp);
-        gc_roots.extend(esp_paths.iter());
+        let esp_paths = EspPaths::new(esp, target_arch);
+        gc_roots.extend(esp_paths.to_iter());
 
         Self {
             broken_gens: BTreeSet::new(),

rust/tool/systemd/tests/common/mod.rs

@@ -156,6 +156,8 @@ pub fn lanzaboote_install(
         .env("LANZABOOTE_STUB", test_systemd_stub)
         .arg("-vv")
         .arg("install")
+        .arg("--system")
+        .arg(TARGET_SYSTEM_DOUBLE)
         .arg("--systemd")
         .arg(test_systemd)
         .arg("--systemd-boot-loader-config")

rust/tool/systemd/tests/systemd_boot.rs

@@ -2,6 +2,8 @@ use std::fs;
 use std::path::PathBuf;
 
 use anyhow::Result;
+use lanzaboote_tool::architecture::Architecture;
+use lzbt_systemd::architecture::SystemdArchitectureExt;
 use tempfile::tempdir;
 
 mod common;
@@ -113,9 +115,15 @@ fn overwrite_unsigned_systemd_boot_binaries() -> Result<()> {
 }
 
 fn systemd_boot_path(esp: &tempfile::TempDir) -> PathBuf {
-    esp.path().join("EFI/systemd/systemd-bootx64.efi")
+    let arch = Architecture::from_nixos_system(TARGET_SYSTEM_DOUBLE).unwrap();
+    esp.path()
+        .join("EFI/systemd/")
+        .join(arch.systemd_filename())
 }
 
 fn systemd_boot_fallback_path(esp: &tempfile::TempDir) -> PathBuf {
-    esp.path().join("EFI/BOOT/BOOTX64.EFI")
+    let arch = Architecture::from_nixos_system(TARGET_SYSTEM_DOUBLE).unwrap();
+    esp.path()
+        .join("EFI/BOOT/")
+        .join(arch.efi_fallback_filename())
 }