iOS: Fix loading of xcframework dynamic libraries.

The logic used to determine whether to invoke the in-memory registration or to
delegate the loading of a library is incorrect for xcframework packages - as
these can contain either static or dynamic libraries.

This change instead lets the operating system handle the library request, and if
it fails, it attempts to load from the internal registry.

With this change, xcframeworks containing dynamic libraries work without
workarounds on iOS.

With an additional fallback case courtesy of @bruvzg

This fixes godotengine#112783

Author: migueldeicaza

core/extension/gdextension_library_loader.cpp

@@ -195,9 +195,13 @@ Error GDExtensionLibraryLoader::open_library(const String &p_path) {
 		&abs_dependencies_paths, // library_dependencies
 	};
 
-	err = OS::get_singleton()->open_dynamic_library(is_static_library ? String() : abs_path, library, &data);
+	// Apple has a complex lookup system which goes beyond looking up the filename, so we try that first.
+	err = OS::get_singleton()->open_dynamic_library(abs_path, library, &data);
 	if (err != OK) {
-		return err;
+		err = OS::get_singleton()->open_dynamic_library(String(), library, &data);
+		if (err != OK) {
+			return err;
+		}
 	}
 
 	return OK;
@@ -361,8 +365,6 @@ Error GDExtensionLibraryLoader::parse_gdextension_file(const String &p_path) {
 		return ERR_FILE_NOT_FOUND;
 	}
 
-	is_static_library = library_path.ends_with(".a") || library_path.ends_with(".xcframework");
-
 	if (!library_path.is_resource_file() && !library_path.is_absolute_path()) {
 		library_path = p_path.get_base_dir().path_join(library_path);
 	}

core/extension/gdextension_library_loader.h

@@ -49,8 +49,6 @@ class GDExtensionLibraryLoader : public GDExtensionLoader {
 	String library_path;
 	String entry_symbol;
 
-	bool is_static_library = false;
-
 #ifdef TOOLS_ENABLED
 	bool is_reloadable = false;
 #endif

drivers/apple_embedded/os_apple_embedded.mm

@@ -279,6 +279,11 @@ Rect2 fit_keep_aspect_covered(const Vector2 &p_container, const Vector2 &p_rect)
 		path = get_framework_executable(get_executable_path().get_base_dir().path_join(p_path.get_file().get_basename() + ".framework"));
 	}
 
+	if (!FileAccess::exists(path)) {
+		// Load .dylib from within the executable path.
+		path = get_framework_executable(get_executable_path().get_base_dir().path_join(p_path.get_file().get_basename() + ".dylib"));
+	}
+
 	if (!FileAccess::exists(path)) {
 		// Load .dylib or framework from a standard iOS location.
 		path = get_framework_executable(get_executable_path().get_base_dir().path_join("Frameworks").path_join(p_path.get_file()));
@@ -289,8 +294,16 @@ Rect2 fit_keep_aspect_covered(const Vector2 &p_container, const Vector2 &p_rect)
 		path = get_framework_executable(get_executable_path().get_base_dir().path_join("Frameworks").path_join(p_path.get_file().get_basename() + ".framework"));
 	}
 
-	ERR_FAIL_COND_V(!FileAccess::exists(path), ERR_FILE_NOT_FOUND);
+	if (!FileAccess::exists(path)) {
+		// Load .dylib from a standard iOS location.
+		path = get_framework_executable(get_executable_path().get_base_dir().path_join("Frameworks").path_join(p_path.get_file().get_basename() + ".dylib"));
+	}
 
+	if (!FileAccess::exists(path) && (p_path.ends_with(".a") || p_path.ends_with(".xcframework"))) {
+		path = String(); // Try loading static library.
+	} else {
+		ERR_FAIL_COND_V(!FileAccess::exists(path), ERR_FILE_NOT_FOUND);
+	}
 	p_library_handle = dlopen(path.utf8().get_data(), RTLD_NOW);
 	ERR_FAIL_NULL_V_MSG(p_library_handle, ERR_CANT_OPEN, vformat("Can't open dynamic library: %s. Error: %s.", p_path, dlerror()));