From 101269a3a8a5a8b68ebf085f514fc8324dd0a596 Mon Sep 17 00:00:00 2001
From: Edoardo Lolletti <edoardo762@gmail.com>
Date: Sat, 27 Apr 2024 12:42:32 +0200
Subject: [PATCH] Properly map to "sd" deviceList path, even if it says "nand"

Hiya passes the appname as nand:/, but the nand device is set as being external storage, so is actually mapped to the sd, account for that
---
 arm9/src/deviceList.c | 38 ++++++++++++++++++++++++++++++++++----
 1 file changed, 34 insertions(+), 4 deletions(-)

diff --git a/arm9/src/deviceList.c b/arm9/src/deviceList.c
index 83c7351..584c0bc 100644
--- a/arm9/src/deviceList.c
+++ b/arm9/src/deviceList.c
@@ -4,19 +4,49 @@
 #define DEVICE_LIST_SENTINEL *(vu32*)0x02300020
 #define DEVICE_LIST_ADDR (vu8*)0x02300024
 
+size_t getDeviceNameLenFromAppName(const char (appname)[0x40])
+{
+	for(int i = 0; i < 0x40; ++i)
+	{
+		if(appname[i] == ':')
+		{
+			return i;
+		}
+	}
+	return 0;
+}
+
 DeviceList* getDeviceList(void)
 {
 	static bool gotDeviceList = false;
 	if(!gotDeviceList) {
 		while(!DEVICE_LIST_SENTINEL);
 		DeviceList* list = (DeviceList*)DEVICE_LIST_ADDR;
-		bool isSd = strncmp(list->appname, "sdmc", 4) == 0;
-		if(!isSd && strncmp(list->appname, "nand", 4) != 0)
+		
+		size_t deviceNameLen = getDeviceNameLenFromAppName(list->appname);
+		
+		if(deviceNameLen == 0)
+		{
 			return 0;
+		}
+		bool isSd = false;
+		
+		for(int i = 0; i < 11; ++i)
+		{
+			Device* device = &list->devices[i];
+			if(device->deviceName[deviceNameLen] == '\0' && strncmp(device->deviceName, list->appname, deviceNameLen) == 0)
+			{
+				isSd = device->phisicalDrive == 0;
+				break;
+			}
+		}
+		
 		if(isSd)
 		{
-			//transform sdmc:/ to sd:/
-			memmove(list->appname + 2, list->appname + 4, sizeof(list->appname) - 4);
+			//transform the root path to sd:/ (can be sdmc:/, nand:/,  nand2:/, etc)
+			memmove(list->appname + (deviceNameLen - 2), list->appname + deviceNameLen, sizeof(list->appname) - deviceNameLen);
+			list->appname[0] = 's';
+			list->appname[1] = 'd';
 			list->appname[sizeof(list->appname) - 1] = '\0';
 			list->appname[sizeof(list->appname) - 2] = '\0';
 		}