1 files changed, 69 insertions, 0 deletions
diff --git a/src/port/win32ntdll.c b/src/port/win32ntdll.c
new file mode 100644
index 0000000..10c33c6
--- /dev/null
+++ b/src/port/win32ntdll.c
@@ -0,0 +1,69 @@
+/*-------------------------------------------------------------------------
+ *
+ * win32ntdll.c
+ *	  Dynamically loaded Windows NT functions.
+ *
+ * Portions Copyright (c) 2021-2022, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
+ *
+ *
+ * IDENTIFICATION
+ *	  src/port/win32ntdll.c
+ *
+ *-------------------------------------------------------------------------
+ */
+
+#define UMDF_USING_NTSTATUS
+
+#include "c.h"
+
+#include "port/win32ntdll.h"
+
+RtlGetLastNtStatus_t pg_RtlGetLastNtStatus;
+
+typedef struct NtDllRoutine
+{
+	const char *name;
+	pg_funcptr_t *address;
+} NtDllRoutine;
+
+static const NtDllRoutine routines[] = {
+	{"RtlGetLastNtStatus", (pg_funcptr_t *) &pg_RtlGetLastNtStatus}
+};
+
+static bool initialized;
+
+int
+initialize_ntdll(void)
+{
+	HMODULE		module;
+
+	if (initialized)
+		return 0;
+
+	if (!(module = LoadLibraryEx("ntdll.dll", NULL, 0)))
+	{
+		_dosmaperr(GetLastError());
+		return -1;
+	}
+
+	for (int i = 0; i < lengthof(routines); ++i)
+	{
+		pg_funcptr_t address;
+
+		address = (pg_funcptr_t) GetProcAddress(module, routines[i].name);
+		if (!address)
+		{
+			_dosmaperr(GetLastError());
+			FreeLibrary(module);
+
+			return -1;
+		}
+
+		*(pg_funcptr_t *) routines[i].address = address;
+	}
+
+	initialized = true;
+
+	return 0;
+}