From b845992d44d5a05a6a5bf6a3c8df8ea903bf9aa0 Mon Sep 17 00:00:00 2001
From: Maschell <Maschell@gmx.de>
Date: Mon, 14 Feb 2022 19:25:54 +0100
Subject: [PATCH] Guard access to global variables with mutex

---
 src/FileWrapper.cpp | 12 +++++++++---
 src/fileinfos.cpp   | 28 ++++++++++++++++++++++------
 src/main.cpp        | 14 ++++++++++++--
 3 files changed, 43 insertions(+), 11 deletions(-)

diff --git a/src/FileWrapper.cpp b/src/FileWrapper.cpp
index ec8cfa7..aeb358c 100644
--- a/src/FileWrapper.cpp
+++ b/src/FileWrapper.cpp
@@ -2,6 +2,7 @@
 #include "fileinfos.h"
 #include "utils/logger.h"
 #include <coreinit/cache.h>
+#include <coreinit/mutex.h>
 #include <cstdio>
 #include <cstdlib>
 #include <cstring>
@@ -9,15 +10,20 @@
 
 FileHandleWrapper gFileHandleWrapper[FILE_WRAPPER_SIZE] __attribute__((section(".data")));
 
+extern OSMutex fileWrapperMutex;
+
 int FileHandleWrapper_GetSlot() {
+    OSLockMutex(&fileWrapperMutex);
+    int res = -1;
     for (int i = 0; i < FILE_WRAPPER_SIZE; i++) {
         if (!gFileHandleWrapper[i].inUse) {
             gFileHandleWrapper[i].inUse = true;
-            DCFlushRange(&gFileHandleWrapper[i], sizeof(FileHandleWrapper));
-            return i;
+            res                         = i;
         }
     }
-    return -1;
+    OSMemoryBarrier();
+    OSUnlockMutex(&fileWrapperMutex);
+    return res;
 }
 
 int OpenFileForID(int id, const char *filepath, int *handle) {
diff --git a/src/fileinfos.cpp b/src/fileinfos.cpp
index a5e59af..c2a5172 100644
--- a/src/fileinfos.cpp
+++ b/src/fileinfos.cpp
@@ -1,24 +1,33 @@
 #include "fileinfos.h"
 #include "utils/logger.h"
+#include <coreinit/cache.h>
+#include <coreinit/mutex.h>
+#include <cstdio>
 #include <cstring>
 #include <rpxloader.h>
-#include <stdio.h>
 
 FileInfos gFileInfos[FILE_INFO_SIZE] __attribute__((section(".data")));
+extern OSMutex fileinfoMutex;
 
 int32_t getIDByLowerTitleID(uint32_t lowerTitleID) {
+    OSLockMutex(&fileinfoMutex);
+    int res = -1;
     for (int i = 0; i < FILE_INFO_SIZE; i++) {
         if (strlen(gFileInfos[i].path) > 0 && gFileInfos[i].lowerTitleID == lowerTitleID) {
-            return i;
+            res = i;
+            break;
         }
     }
-    return -1;
+    OSMemoryBarrier();
+    OSUnlockMutex(&fileinfoMutex);
+    return res;
 }
 
 void unmountRomfs(uint32_t id) {
     if (id >= FILE_INFO_SIZE) {
         return;
     }
+    OSLockMutex(&fileinfoMutex);
     if (gFileInfos[id].romfsMounted) {
         char romName[10];
         snprintf(romName, 10, "%08X", id);
@@ -27,6 +36,8 @@ void unmountRomfs(uint32_t id) {
         DEBUG_FUNCTION_LINE("res: %d", res);
         gFileInfos[id].romfsMounted = false;
     }
+    OSMemoryBarrier();
+    OSUnlockMutex(&fileinfoMutex);
 }
 
 void unmountAllRomfs() {
@@ -40,6 +51,8 @@ bool mountRomfs(uint32_t id) {
         DEBUG_FUNCTION_LINE("HANDLE WAS TOO BIG %d", id);
         return false;
     }
+    OSLockMutex(&fileinfoMutex);
+    bool result = false;
     if (!gFileInfos[id].romfsMounted) {
         char buffer[256];
         snprintf(buffer, 256, "/vol/external01/%s", gFileInfos[id].path);
@@ -50,11 +63,14 @@ bool mountRomfs(uint32_t id) {
         if ((res = RL_MountBundle(romName, buffer, BundleSource_FileDescriptor_CafeOS)) == 0) {
             DEBUG_FUNCTION_LINE("Mounted successfully ");
             gFileInfos[id].romfsMounted = true;
-            return true;
+            result                      = true;
         } else {
             DEBUG_FUNCTION_LINE("Mounting failed %d", res);
-            return false;
+            result = false;
         }
     }
-    return true;
+
+    OSMemoryBarrier();
+    OSUnlockMutex(&fileinfoMutex);
+    return result;
 }
\ No newline at end of file
diff --git a/src/main.cpp b/src/main.cpp
index 8358729..8aa0750 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -8,6 +8,7 @@
 #include <coreinit/debug.h>
 #include <coreinit/filesystem.h>
 #include <coreinit/mcp.h>
+#include <coreinit/mutex.h>
 #include <coreinit/systeminfo.h>
 #include <coreinit/title.h>
 #include <cstring>
@@ -49,11 +50,16 @@ extern "C" void _SYSLaunchTitleWithStdArgsInNoSplash(uint64_t, uint32_t);
 
 WUPS_USE_WUT_DEVOPTAB();
 
+OSMutex fileWrapperMutex;
+OSMutex fileinfoMutex;
+
 INITIALIZE_PLUGIN() {
     memset((void *) &current_launched_title_info, 0, sizeof(current_launched_title_info));
     memset((void *) &gLaunchXML, 0, sizeof(gLaunchXML));
     memset((void *) &gFileInfos, 0, sizeof(gFileInfos));
     gHomebrewLaunched = FALSE;
+    OSInitMutex(&fileWrapperMutex);
+    OSInitMutex(&fileinfoMutex);
 }
 
 ON_APPLICATION_START() {
@@ -266,6 +272,7 @@ DECL_FUNCTION(int32_t, MCP_TitleList, uint32_t handle, uint32_t *outTitleCount,
     int32_t result      = real_MCP_TitleList(handle, outTitleCount, titleList, size);
     uint32_t titlecount = *outTitleCount;
 
+    OSLockMutex(&fileinfoMutex);
     for (auto &gFileInfo : gFileInfos) {
         if (gFileInfo.lowerTitleID == 0) {
             break;
@@ -273,6 +280,7 @@ DECL_FUNCTION(int32_t, MCP_TitleList, uint32_t handle, uint32_t *outTitleCount,
         memcpy(&(titleList[titlecount]), &(gFileInfo.titleInfo), sizeof(gFileInfo.titleInfo));
         titlecount++;
     }
+    OSUnlockMutex(&fileinfoMutex);
 
     *outTitleCount = titlecount;
 
@@ -343,8 +351,9 @@ DECL_FUNCTION(FSStatus, FSCloseFile, FSClient *client, FSCmdBlock *block, FSFile
     if (handle == 0x13371338) {
         return FS_STATUS_OK;
     } else if ((handle & 0xFF000000) == 0xFF000000) {
-        int32_t fd         = (handle & 0x00000FFF);
-        int32_t romid      = (handle & 0x00FFF000) >> 12;
+        int32_t fd    = (handle & 0x00000FFF);
+        int32_t romid = (handle & 0x00FFF000) >> 12;
+        OSLockMutex(&fileinfoMutex);
         uint32_t rl_handle = gFileHandleWrapper[fd].handle;
         RL_FileClose(rl_handle);
         if (gFileInfos[romid].openedFiles--) {
@@ -354,6 +363,7 @@ DECL_FUNCTION(FSStatus, FSCloseFile, FSClient *client, FSCmdBlock *block, FSFile
                 unmountRomfs(romid);
             }
         }
+        OSUnlockMutex(&fileinfoMutex);
         return FS_STATUS_OK;
     }
     return real_FSCloseFile(client, block, handle, flags);