1 files changed, 41 insertions, 0 deletions
diff --git a/NorthstarDLL/sigscanning.cpp b/NorthstarDLL/sigscanning.cpp
new file mode 100644
index 00000000..761f9f08
--- /dev/null
+++ b/NorthstarDLL/sigscanning.cpp
@@ -0,0 +1,41 @@
+#include "pch.h"
+#include "sigscanning.h"
+#include <map>
+
+// note: sigscanning is only really intended to be used for resolving stuff like shared function definitions
+// we mostly use raw function addresses for stuff
+
+size_t GetModuleLength(HMODULE moduleHandle)
+{
+	// based on sigscn code from ttf2sdk, which is in turn based on CSigScan from https://wiki.alliedmods.net/Signature_Scanning
+	MEMORY_BASIC_INFORMATION mem;
+	VirtualQuery(moduleHandle, &mem, sizeof(mem));
+
+	IMAGE_DOS_HEADER* dos = (IMAGE_DOS_HEADER*)mem.AllocationBase;
+	IMAGE_NT_HEADERS* pe = (IMAGE_NT_HEADERS*)((unsigned char*)dos + dos->e_lfanew);
+
+	return pe->OptionalHeader.SizeOfImage;
+}
+
+void* FindSignature(std::string dllName, const char* sig, const char* mask)
+{
+	HMODULE module = GetModuleHandleA(dllName.c_str());
+
+	unsigned char* dllAddress = (unsigned char*)module;
+	unsigned char* dllEnd = dllAddress + GetModuleLength(module);
+
+	size_t sigLength = strlen(mask);
+
+	for (auto i = dllAddress; i < dllEnd - sigLength + 1; i++)
+	{
+		int j = 0;
+		for (; j < sigLength; j++)
+			if (mask[j] != '?' && sig[j] != i[j])
+				break;
+
+		if (j == sigLength) // loop finished of its own accord
+			return i;
+	}
+
+	return nullptr;
+}