From 785307c0e2da48c1f66f1170aa50177c9a2817cd Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Lauri=20Kentt=C3=A4?= <lauri.kentta@gmail.com>
Date: Fri, 21 Mar 2025 19:33:31 +0200
Subject: [PATCH] Allow overriding ESP path

---
 README.md    |  1 +
 src/Setup.cs | 11 ++++++++++-
 2 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/README.md b/README.md
index bce193b..1dcf4e4 100644
--- a/README.md
+++ b/README.md
@@ -53,6 +53,7 @@ The *shim* boot loader is maintained by Red Hat, Inc, and the included signed co
 	* `uninstall` – disable and remove completely.
 	* `show-boot-log` – show the debug log collected during boot (if `log=1` is set in `config.txt`).
 	* `arch=...` – force architecture.
+	* `esp=...` – force EFI System Partition path.
 	* `dry-run` – skip actual changes.
 * For example, run `setup.exe batch install allow-secure-boot enable-overwrite` to copy files and overwrite the MS boot loader regardless of Secure Boot status.
 
diff --git a/src/Setup.cs b/src/Setup.cs
index f89ba9f..6a5eba1 100644
--- a/src/Setup.cs
+++ b/src/Setup.cs
@@ -106,6 +106,9 @@ public class Setup {
 	/** @var Dry run? */
 	protected bool DryRun;
 
+	/** @var User-defined ESP path */
+	protected string UserEspPath;
+
 	/** @var Run in batch mode? */
 	protected bool Batch;
 
@@ -289,6 +292,11 @@ public class Setup {
 		if (DryRun) {
 			Directory.CreateDirectory(Path.Combine("dry-run", "EFI"));
 			Esp.TryPath("dry-run", false);
+		} else if (UserEspPath != null) {
+			WriteLine($"Using user-defined ESP path: {UserEspPath}");
+			if (!Esp.TryPath(UserEspPath, false)) {
+				throw new SetupException("The ESP path doesn't look like an EFI System Partition.");
+			}
 		}
 		if (Esp.Location == null && !Esp.Find() && !Esp.Mount() && !Batch) {
 			WriteLine("EFI System Partition was not found.");
@@ -1045,7 +1053,7 @@ public class Setup {
 		AllowSecureBoot = args.Contains("allow-secure-boot");
 		AllowBitLocker = args.Contains("allow-bitlocker");
 		SkipShim = args.Contains("skip-shim");
-		ForwardArguments = String.Join(" ", args.Where(s => ForwardableArguments.Contains(s) || s.StartsWith("arch=")));
+		ForwardArguments = String.Join(" ", args.Where(s => ForwardableArguments.Contains(s) || s.StartsWith("arch=") || s.StartsWith("esp=")));
 		try {
 			if (!(Directory.Exists("efi") || Directory.Exists("efi-signed")) || !File.Exists("config.txt")) {
 				WriteLine("This setup program is not in the correct directory!");
@@ -1053,6 +1061,7 @@ public class Setup {
 				return 1;
 			}
 			SetArch(args.Where(s => s.StartsWith("arch=")).Select(s => s.Substring(5)).LastOrDefault());
+			UserEspPath = args.Where(s => s.StartsWith("esp=")).Select(s => s.Substring(4)).LastOrDefault();
 			if (args.Contains("is-elevated") && !HasPrivileges() && !DryRun) {
 				WriteLine("This installer needs to be run as administrator!");
 				return 1;