From e8956ae02ed780cd2e7e390c646eb12fa656d582 Mon Sep 17 00:00:00 2001
From: Edoardo Lolletti <edoardo762@gmail.com>
Date: Thu, 25 Apr 2024 15:37:31 +0200
Subject: [PATCH] Fix unlaunch being wrongly detected as installed

---
 arm9/src/main.c     |  7 ++++++-
 arm9/src/unlaunch.c | 14 ++++++++++++++
 arm9/src/unlaunch.h |  2 ++
 3 files changed, 22 insertions(+), 1 deletion(-)

diff --git a/arm9/src/main.c b/arm9/src/main.c
index 6a99a10..8f730a5 100644
--- a/arm9/src/main.c
+++ b/arm9/src/main.c
@@ -203,6 +203,7 @@ int main(int argc, char **argv)
 	const char* hnaaTmdPath = "nand:/title/00030017/484e4141/content/title.tmd";
 	{
 		FILE* file = fopen("nand:/sys/HWINFO_S.dat", "rb");
+		bool mainTmdIsPatched = false;
 		if (file)
 		{
 			fseek(file, 0xA0, SEEK_SET);
@@ -224,6 +225,10 @@ int main(int argc, char **argv)
 				//if size isn't 520 then the tmd either is not present (size 0), or is already invalid, thus no need to patch
 				retailLauncherTmdPresentAndToBePatched = false;
 			}
+			else
+			{
+				mainTmdIsPatched = isLauncherTmdPatched(retailLauncherTmdPath);
+			}
 			// HWINFO_S may not always exist (PRE_IMPORT). Fill in defaults if that happens.
 		}
 		
@@ -231,7 +236,7 @@ int main(int argc, char **argv)
 		// These can normally be identified by having the region set to ALL (0x41)
 		retailConsole = (region != 0x41 && region != 0xFF);
 		
-		if (!unlaunchFound)
+		if (!unlaunchFound && (mainTmdIsPatched || !retailConsole))
 		{
 			unsigned long long tmdSize = getFileSizePath(hnaaTmdPath);
 			if (tmdSize > 520)
diff --git a/arm9/src/unlaunch.c b/arm9/src/unlaunch.c
index cb20f27..da665fb 100644
--- a/arm9/src/unlaunch.c
+++ b/arm9/src/unlaunch.c
@@ -8,6 +8,20 @@
 static char unlaunchInstallerBuffer[0x30000];
 static const char* hnaaTmdPath = "nand:/title/00030017/484e4141/content/title.tmd";
 
+bool isLauncherTmdPatched(const char* path)
+{
+	FILE* launcherTmd = fopen(path, "rb");
+	if(!launcherTmd)
+	{
+		return false;
+	}
+	fseek(launcherTmd, 0x190, SEEK_SET);
+	char c;
+	fread(&c, 1, 1, launcherTmd);
+	fclose(launcherTmd);
+	return c == 0x47;
+}
+
 static bool restoreMainTmd(const char* path)
 {
 	FILE* launcherTmd = fopen(path, "r+b");
diff --git a/arm9/src/unlaunch.h b/arm9/src/unlaunch.h
index 4c74d6b..bbc5cee 100644
--- a/arm9/src/unlaunch.h
+++ b/arm9/src/unlaunch.h
@@ -5,4 +5,6 @@
 bool uninstallUnlaunch(bool notProto, const char* retailLauncherTmdPath);
 bool installUnlaunch(bool retailConsole, const char* retailLauncherTmdPath);
 
+bool isLauncherTmdPatched(const char* path);
+
 #endif
\ No newline at end of file