WinUpdater: Removed MAX_PATH limitation on path to updater, also fixed a wrong size parameter

Source/Core/WinUpdater/Main.cpp

@@ -6,6 +6,7 @@
 #include <ShlObj.h>
 #include <shellapi.h>
 
+#include <optional>
 #include <string>
 #include <vector>
 
@@ -32,6 +33,28 @@ std::vector<std::string> CommandLineToUtf8Argv(PCWSTR command_line)
   LocalFree(tokenized);
   return argv;
 }
+
+std::optional<std::wstring> GetModuleName(HINSTANCE hInstance)
+{
+  std::wstring name;
+  DWORD max_size = 50;  // Start with space for 50 characters and grow if needed
+  name.resize(max_size);
+
+  DWORD size;
+  while ((size = GetModuleFileNameW(hInstance, name.data(), max_size)) == max_size &&
+         GetLastError() == ERROR_INSUFFICIENT_BUFFER)
+  {
+    max_size *= 2;
+    name.resize(max_size);
+  }
+
+  if (size == 0)
+  {
+    return {};
+  }
+  name.resize(size);
+  return name;
+}
 };  // namespace
 
 int WINAPI wWinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, PWSTR pCmdLine, int nCmdShow)
@@ -64,15 +87,15 @@ int WINAPI wWinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, PWSTR pCmdLine
       return 1;
     }
 
-    wchar_t path[MAX_PATH];
+    auto path = GetModuleName(hInstance);
-    if (GetModuleFileName(hInstance, path, sizeof(path)) == 0)
+    if (!path)
     {
       MessageBox(nullptr, L"Failed to get updater filename.", L"Error", MB_ICONERROR);
       return 1;
     }
 
     // Relaunch the updater as administrator
-    ShellExecuteW(nullptr, L"runas", path, pCmdLine, NULL, SW_SHOW);
+    ShellExecuteW(nullptr, L"runas", path->c_str(), pCmdLine, NULL, SW_SHOW);
     return 0;
   }