From 1237946a8daa0ebdcee5d2eb1dc2274cbf846c27 Mon Sep 17 00:00:00 2001
From: Wojtek Figat <wojtek@figat.pl>
Date: Wed, 16 Jun 2021 23:39:05 +0200
Subject: [PATCH] Fix synchronization for dbg symbols on Windows

---
 .../Platform/Windows/WindowsPlatform.cpp      | 39 ++++++++++++++-----
 Source/ThirdParty/tracy/tracy.Build.cs        |  2 +
 2 files changed, 32 insertions(+), 9 deletions(-)

diff --git a/Source/Engine/Platform/Windows/WindowsPlatform.cpp b/Source/Engine/Platform/Windows/WindowsPlatform.cpp
index 89e050267..52b0bdaa3 100644
--- a/Source/Engine/Platform/Windows/WindowsPlatform.cpp
+++ b/Source/Engine/Platform/Windows/WindowsPlatform.cpp
@@ -29,6 +29,28 @@
 const Char* WindowsPlatform::ApplicationWindowClass = TEXT("FlaxWindow");
 void* WindowsPlatform::Instance = nullptr;
 
+#if CRASH_LOG_ENABLE || TRACY_ENABLE
+// Lock for symbols list, shared with Tracy
+extern "C" {
+static HANDLE dbgHelpLock;
+
+void DbgHelpInit()
+{
+    dbgHelpLock = CreateMutexW(nullptr, FALSE, nullptr);
+}
+
+void DbgHelpLock()
+{
+    WaitForSingleObject(dbgHelpLock, INFINITE);
+}
+
+void DbgHelpUnlock()
+{
+    ReleaseMutex(dbgHelpLock);
+}
+}
+#endif
+
 namespace
 {
     String UserLocale, ComputerName, UserName, WindowsName;
@@ -39,7 +61,6 @@ namespace
     int32 VersionBuild = 0;
     int32 SystemDpi = 96;
 #if CRASH_LOG_ENABLE
-    CriticalSection SymLocker;
 #if TRACY_ENABLE
     bool SymInitialized = true;
 #else
@@ -501,7 +522,7 @@ void WindowsPlatform::PreInit(void* hInstance)
 
 #if CRASH_LOG_ENABLE
     TCHAR buffer[MAX_PATH] = { 0 };
-    SymLocker.Lock();
+    DbgHelpLock();
     if (::GetModuleFileNameW(::GetModuleHandleW(nullptr), buffer, MAX_PATH))
         SymbolsPath.Add(StringUtils::GetDirectoryName(buffer));
     if (::GetEnvironmentVariableW(TEXT("_NT_SYMBOL_PATH"), buffer, MAX_PATH))
@@ -510,7 +531,7 @@ void WindowsPlatform::PreInit(void* hInstance)
     options |= SYMOPT_LOAD_LINES | SYMOPT_FAIL_CRITICAL_ERRORS | SYMOPT_DEFERRED_LOADS | SYMOPT_EXACT_SYMBOLS;
     SymSetOptions(options);
     OnSymbolsPathModified();
-    SymLocker.Unlock();
+    DbgHelpUnlock();
 #endif
 
     GetWindowsVersion(WindowsName, VersionMajor, VersionMinor, VersionBuild);
@@ -654,7 +675,7 @@ void WindowsPlatform::BeforeExit()
 void WindowsPlatform::Exit()
 {
 #if CRASH_LOG_ENABLE
-    SymLocker.Lock();
+    DbgHelpLock();
 #if !TRACY_ENABLE
     if (SymInitialized)
     {
@@ -663,7 +684,7 @@ void WindowsPlatform::Exit()
     }
 #endif
     SymbolsPath.Resize(0);
-    SymLocker.Unlock();
+    DbgHelpUnlock();
 #endif
 
     // Unregister app class
@@ -1170,13 +1191,13 @@ void* WindowsPlatform::LoadLibrary(const Char* filename)
 
 #if CRASH_LOG_ENABLE
     // Refresh modules info during next stack trace collecting to have valid debug symbols information
-    SymLocker.Lock();
+    DbgHelpLock();
     if (folder.HasChars() && !SymbolsPath.Contains(folder))
     {
         SymbolsPath.Add(folder);
         OnSymbolsPathModified();
     }
-    SymLocker.Unlock();
+    DbgHelpUnlock();
 #endif
 
     return handle;
@@ -1186,7 +1207,7 @@ Array<PlatformBase::StackFrame> WindowsPlatform::GetStackFrames(int32 skipCount,
 {
     Array<StackFrame> result;
 #if CRASH_LOG_ENABLE
-    SymLocker.Lock();
+    DbgHelpLock();
 
     // Initialize
     HANDLE process = GetCurrentProcess();
@@ -1310,7 +1331,7 @@ Array<PlatformBase::StackFrame> WindowsPlatform::GetStackFrames(int32 skipCount,
         }
     }
 
-    SymLocker.Unlock();
+    DbgHelpUnlock();
 #endif
     return result;
 }
diff --git a/Source/ThirdParty/tracy/tracy.Build.cs b/Source/ThirdParty/tracy/tracy.Build.cs
index aa10c514f..abcc83da4 100644
--- a/Source/ThirdParty/tracy/tracy.Build.cs
+++ b/Source/ThirdParty/tracy/tracy.Build.cs
@@ -33,6 +33,8 @@ public class tracy : ThirdPartyModule
         options.SourceFiles.Add(Path.Combine(FolderPath, "TracyClient.cpp"));
 
         options.PublicDefinitions.Add("TRACY_ENABLE");
+        if (options.Platform.Target == TargetPlatform.Windows)
+            options.PrivateDefinitions.Add("TRACY_DBGHELP_LOCK=DbgHelp");
     }
 
     /// <inheritdoc />