Introduce reusable TLS in x64dbg.dll

src/dbg/main.cpp

@@ -5,10 +5,13 @@
  */
 
 #include "debugger.h"
+#include "threading.h"
 
 extern "C" DLL_EXPORT BOOL APIENTRY DllMain(HINSTANCE hinstDLL, DWORD fdwReason, LPVOID lpvReserved)
 {
-    if(fdwReason == DLL_PROCESS_ATTACH)
+    switch(fdwReason)
+    {
+    case DLL_PROCESS_ATTACH:
     {
         hInst = hinstDLL;
 
@@ -27,9 +30,12 @@ extern "C" DLL_EXPORT BOOL APIENTRY DllMain(HINSTANCE hinstDLL, DWORD fdwReason,
                 szProgramDir[len] = 0;
             }
         }
+    }
 
-        // https://docs.microsoft.com/en-us/windows/win32/api/libloaderapi/nf-libloaderapi-disablethreadlibrarycalls
-        DisableThreadLibraryCalls(hinstDLL);
+    case DLL_THREAD_ATTACH:
+    {
+
+    }
     }
     return TRUE;
 }

src/dbg/threading.cpp

@@ -145,3 +145,48 @@ void SectionLockerGlobal::Deinitialize()
 
     m_Initialized = false;
 }
+
+static DWORD gTlsIndex = TLS_OUT_OF_INDEXES;
+
+TLSData::TLSData()
+{
+    moduleHashLower.reserve(MAX_MODULE_SIZE);
+}
+
+bool TLSData::notify(DWORD fdwReason)
+{
+    switch(fdwReason)
+    {
+    case DLL_PROCESS_ATTACH:
+        gTlsIndex = TlsAlloc();
+        return gTlsIndex != TLS_OUT_OF_INDEXES;
+
+    case DLL_THREAD_DETACH:
+    {
+        auto data = (TLSData*)TlsGetValue(gTlsIndex);
+        delete data;
+    }
+    return true;
+
+    case DLL_PROCESS_DETACH:
+    {
+        auto data = (TLSData*)TlsGetValue(gTlsIndex);
+        delete data;
+        TlsFree(gTlsIndex);
+    }
+    return true;
+    }
+
+    return false;
+}
+
+TLSData* TLSData::get()
+{
+    auto data = (TLSData*)TlsGetValue(gTlsIndex);
+    if(data == nullptr)
+    {
+        data = new TLSData();
+        TlsSetValue(gTlsIndex, data);
+    }
+    return data;
+}

src/dbg/threading.h

@@ -1,5 +1,4 @@
-#ifndef _THREADING_H
-#define _THREADING_H
+#pragma once
 
 #include "_global.h"
 
@@ -256,4 +255,14 @@ private:
     using Internal = SectionLockerGlobal;
 };
 
-#endif // _THREADING_H
+struct TLSData
+{
+    String moduleHashLower;
+
+    TLSData();
+    TLSData(const TLSData &) = delete;
+    TLSData & operator=(const TLSData &) = delete;
+
+    static bool notify(DWORD fdwReason);
+    static TLSData* get();
+};