build: delay-load node.exe imports so addons work in any Node-API host on Windows

CMakeLists.txt

@@ -40,6 +40,14 @@ function(add_node_api_cts_addon ADDON_NAME)
   endif()
   target_include_directories(${ADDON_NAME} PRIVATE ${NODE_API_HEADERS_DIR})
   target_link_libraries(${ADDON_NAME} PRIVATE ${NODE_API_LIB})
+  if(MSVC)
+    # Delay-load the node.exe imports and resolve them against the host
+    # process at runtime, so the addons can be loaded by any Node-API host
+    # executable regardless of its file name (the node-gyp approach).
+    target_sources(${ADDON_NAME} PRIVATE ${PROJECT_SOURCE_DIR}/src/win_delay_load_hook.cc)
+    target_link_libraries(${ADDON_NAME} PRIVATE delayimp)
+    target_link_options(${ADDON_NAME} PRIVATE "/DELAYLOAD:NODE.EXE")
+  endif()
   target_compile_features(${ADDON_NAME} PRIVATE cxx_std_17)
   target_compile_definitions(${ADDON_NAME} PRIVATE ADDON_NAME=${ADDON_NAME})
 endfunction()

src/win_delay_load_hook.cc

@@ -0,0 +1,39 @@
+/*
+ * When this file is linked to a DLL, it sets up a delay-load hook that
+ * intervenes when the DLL is trying to load 'node.exe' dynamically. Instead
+ * of trying to locate the .exe file it'll just return a handle to the
+ * process image.
+ *
+ * This allows the test addons to load into any Node-API host executable,
+ * regardless of its file name. Same approach as node-gyp's
+ * win_delay_load_hook.cc.
+ */
+
+#ifdef _MSC_VER
+
+#ifndef WIN32_LEAN_AND_MEAN
+#define WIN32_LEAN_AND_MEAN
+#endif
+
+#include <windows.h>
+
+#include <delayimp.h>
+#include <string.h>
+
+static FARPROC WINAPI load_exe_hook(unsigned int event, DelayLoadInfo* info) {
+  HMODULE m;
+  if (event != dliNotePreLoadLibrary)
+    return NULL;
+
+  if (_stricmp(info->szDll, "node.exe") != 0)
+    return NULL;
+
+  // Prefer libnode.dll to support a Node.js built as a shared library.
+  m = GetModuleHandle(TEXT("libnode.dll"));
+  if (m == NULL) m = GetModuleHandle(NULL);
+  return (FARPROC) m;
+}
+
+decltype(__pfnDliNotifyHook2) __pfnDliNotifyHook2 = load_exe_hook;
+
+#endif