Harden LinuxCNC wasm and native probe workflows

core/wasm_shims/dlfcn.cc

@@ -0,0 +1,30 @@
+#include "dlfcn.h"
+
+#include <cstring>
+
+namespace {
+
+thread_local char last_error[128] = "dynamic loading is unavailable in wasm-safe probe";
+
+} // namespace
+
+extern "C" {
+
+void *dlopen(const char *, int) {
+    return nullptr;
+}
+
+void *dlsym(void *, const char *) {
+    return nullptr;
+}
+
+char *dlerror(void) {
+    return last_error;
+}
+
+int dlclose(void *) {
+    return 0;
+}
+
+} // extern "C"
+