Support DLL build by exporting GetMmpGlobalDataPtr()

- problems with exported global at runtime
- wrapping data access in a function allows additional controls

Author: Dan Dees

MemoryModule/Initialize.cpp

@@ -5,6 +5,12 @@
 
 PMMP_GLOBAL_DATA MmpGlobalDataPtr;
 
+// DLL compliant access
+PMMP_GLOBAL_DATA NTAPI GetMmpGlobalDataPtr()
+{
+   return MmpGlobalDataPtr;
+}
+
 #if MEMORY_MODULE_IS_PREVIEW(MEMORY_MODULE_MINOR_VERSION)
 #pragma message("WARNING: You are using a preview version of MemoryModulePP.")
 #endif
@@ -621,6 +627,6 @@ BOOL APIENTRY DllMain(HMODULE hModule, DWORD  ul_reason_for_call, LPVOID lpReser
 }
 #else
 #ifdef _HAS_AUTO_INITIALIZE
-const NTSTATUS Initializer = MmInitialize();
+static const NTSTATUS Initializer = MmInitialize();
 #endif
 #endif

MemoryModule/MemoryModulePP.def

@@ -15,3 +15,4 @@ LdrUnloadDllMemoryAndExitThread
 LdrQuerySystemMemoryModuleFeatures
 
 MmpGlobalDataPtr
+GetMmpGlobalDataPtr

MemoryModule/MmpGlobalData.h

@@ -153,3 +153,4 @@ typedef struct _MMP_GLOBAL_DATA {
 )
 
 extern PMMP_GLOBAL_DATA MmpGlobalDataPtr;
+PMMP_GLOBAL_DATA NTAPI GetMmpGlobalDataPtr() ;

test/test.cpp

@@ -4,7 +4,12 @@
 #include <string>
 #pragma comment(lib,"ntdll.lib")
 
-static void DisplayStatus() {
+static int DisplayStatus() {
+    const auto gdp = GetMmpGlobalDataPtr();
+    if ( !gdp ) {
+        printf("failed GetMmpGlobalDataPtr().\n");
+        return -1 ;
+    }
     printf(
         "\
 MemoryModulePP [Version %d.%d%s]\n\n\t\
@@ -16,17 +21,18 @@ RtlRbRemoveNode = %p\n\n\t\
 LdrpInvertedFunctionTable = %p\n\n\t\
 LdrpHashTable = %p\n\n\
 ",
-        MmpGlobalDataPtr->MajorVersion,
-        MEMORY_MODULE_GET_MINOR_VERSION(MmpGlobalDataPtr->MinorVersion),
-        MEMORY_MODULE_IS_PREVIEW(MmpGlobalDataPtr->MinorVersion) ? " Preview" : "",
-        MmpGlobalDataPtr->MmpFeatures,
-        MmpGlobalDataPtr->MmpBaseAddressIndex->LdrpModuleBaseAddressIndex,
-        MmpGlobalDataPtr->MmpBaseAddressIndex->NtdllLdrEntry,
-        MmpGlobalDataPtr->MmpBaseAddressIndex->_RtlRbInsertNodeEx,
-        MmpGlobalDataPtr->MmpBaseAddressIndex->_RtlRbRemoveNode,
-        MmpGlobalDataPtr->MmpInvertedFunctionTable->LdrpInvertedFunctionTable,
-        MmpGlobalDataPtr->MmpLdrEntry->LdrpHashTable
+        gdp->MajorVersion,
+        MEMORY_MODULE_GET_MINOR_VERSION(gdp->MinorVersion),
+        MEMORY_MODULE_IS_PREVIEW(gdp->MinorVersion) ? " Preview" : "",
+        gdp->MmpFeatures,
+        (PVOID)gdp->MmpBaseAddressIndex->LdrpModuleBaseAddressIndex,
+        (PVOID)gdp->MmpBaseAddressIndex->NtdllLdrEntry,
+        gdp->MmpBaseAddressIndex->_RtlRbInsertNodeEx,
+        gdp->MmpBaseAddressIndex->_RtlRbRemoveNode,
+        gdp->MmpInvertedFunctionTable->LdrpInvertedFunctionTable,
+        (PVOID)gdp->MmpLdrEntry->LdrpHashTable
     );
+    return 0 ;
 }
 
 static PVOID ReadDllFile(const std::string& FilePath) {
@@ -141,7 +147,10 @@ int test(const std::string& dll_path) {
 
 int main(int argc, char* argv[]) {
 
-    DisplayStatus();
+    // check MemoryModulePP initialization
+    if ( DisplayStatus() ) {
+        return -1 ;
+    }
 
     std::string dll_path("a.dll"); // default
     dll_path = argc > 1 ?  argv[1] : ResolveWithModulePath(dll_path);