Backport import function target IDs (#70)

examples/wasm-test/.godot/global_script_class_cache.cfg

@@ -5,6 +5,12 @@ list=Array[Dictionary]([{
 "language": &"GDScript",
 "path": "res://utils/GodotWasmTestSuite.gd"
 }, {
+"base": &"Object",
+"class": &"ImportTarget",
+"icon": "",
+"language": &"GDScript",
+"path": "res://utils/ImportTarget.gd"
+}, {
 "base": &"Node",
 "class": &"TestRunner",
 "icon": "",

examples/wasm-test/TestImports.gd

@@ -43,6 +43,43 @@ func test_invalid_imports():
 	expect_eq(error, ERR_CANT_CREATE)
 	expect_error("Invalid import method import.import_int")
 
+func test_instantiation_freed_target():
+	var target = ImportTarget.new()
+	var imports = { "functions": {
+		"import.import_int": target.dummy_import(),
+		"import.import_float": target.dummy_import(),
+	} }
+	var wasm = Wasm.new()
+	var buffer = read_file("import")
+	var error = wasm.compile(buffer)
+	expect_eq(error, OK)
+	target.free() # Free target before instantiation
+	error = wasm.instantiate(imports)
+	expect_eq(error, ERR_CANT_CREATE)
+	expect_error("Invalid import target import.import_(int|float)")
+
+func test_invocation_freed_target():
+	var target = ImportTarget.new()
+	var imports = { "functions": {
+		"import.import_int": target.dummy_import(),
+		"import.import_float": target.dummy_import(),
+	} }
+	var wasm = load_wasm("import", imports)
+	target.free() # Free target before invocation
+	wasm.function("callback", [])
+	expect_error("Failed to retrieve import function target")
+	expect_error("Failed calling function callback")
+
+func test_import_method_missing():
+	var imports = { "functions": {
+		"import.import_int": [self, "invalid_method_0"],
+		"import.import_float": [self, "invalid_method_1"],
+	} }
+	var wasm = load_wasm("import", imports)
+	wasm.function("callback", [])
+	expect_error(".*::invalid_method_0': Method not found.*")
+	expect_error(".*::invalid_method_1': Method not found.*")
+
 func test_callback_function():
 	var imports = { "functions": {
 		"import.import_int": dummy_import(),

examples/wasm-test/utils/ImportTarget.gd

@@ -0,0 +1,11 @@
+extends Object
+class_name ImportTarget
+
+# Dummy import to supply to Wasm modules
+static func _dummy_import(a = "", b = "", c = "", d = ""):
+	var message = "Dummy import %s %s %s %s" % [a, b, c, d]
+	print(message.strip_edges())
+	return a
+
+func dummy_import() -> Array:
+	return [self, "_dummy_import"]

examples/wasm-test/utils/Utils.gd

@@ -2,7 +2,7 @@ extends Object
 class_name Utils
 
 static func comparable(o):
-	return o.hash() if (o is Dictionary or o is Object) else o
+	return o.hash() if ((o is Dictionary or o is Object) and o != null) else o
 
 static func make_regex(pattern: String) -> RegEx:
 	var regex = RegEx.new()

register_types.cpp

@@ -2,7 +2,7 @@
 
 #include "register_types.h"
 #include "core/class_db.h"
-#include "src/godot-wasm.h"
+#include "src/wasm.h"
 #include "src/wasm-memory.h"
 
 void register_wasm_types() {

src/defs.h

@@ -7,9 +7,9 @@ Useful for minimizing changes to implementation files between targets e.g. GDExt
 */
 
 #ifdef GODOT_MODULE // Godot includes when building module
-  #include "core/os/os.h"
-  #include "core/crypto/crypto.h"
-  #include "core/io/stream_peer.h"
+  #include <core/os/os.h>
+  #include <core/crypto/crypto.h>
+  #include <core/io/stream_peer.h>
 #else // Godot addon includes
   #include <Godot.hpp>
   #include <OS.hpp>
@@ -18,9 +18,11 @@ Useful for minimizing changes to implementation files between targets e.g. GDExt
 #endif
 
 #ifdef GODOT_MODULE
-  #define godot_error Error
   #define PRINT(message) print_line(String(message))
   #define PRINT_ERROR(message) print_error("Godot Wasm: " + String(message))
+  #define godot_error Error
+  #define INSTANCE_FROM_ID(id) ObjectDB::get_instance(id)
+  #define INSTANCE_VALIDATE(id) VariantUtilityFunctions::is_instance_valid(id)
   #define REGISTRATION_METHOD _bind_methods
   #define RANDOM_BYTES(n) Crypto::create()->generate_random_bytes(n)
 #else
@@ -32,6 +34,8 @@ Useful for minimizing changes to implementation files between targets e.g. GDExt
   #define ERR_PARAMETER_RANGE_ERROR GODOT_ERR_PARAMETER_RANGE_ERROR
   #define PRINT(message) Godot::print(String(message))
   #define PRINT_ERROR(message) Godot::print_error("Godot Wasm: " + String(message), __func__, __FILE__, __LINE__)
+  #define INSTANCE_FROM_ID(id) ObjectDB::get_instance(id)
+  #define INSTANCE_VALIDATE(id) UtilityFunctions::is_instance_valid(id)
   #define GDCLASS GODOT_CLASS
   #define REGISTRATION_METHOD _register_methods
   #define RANDOM_BYTES(n) Crypto::_new()->generate_random_bytes(n)

src/store.h

@@ -6,7 +6,7 @@ Singleton Wasm C API store
 The same store is used between all compiled Wasm modules
 */
 
-#include "wasm.h"
+#include <wasm.h>
 
 #define STORE ::godot_wasm::Store::instance().store
 

src/wasi-shim.cpp

@@ -2,7 +2,7 @@
 #include <vector>
 #include <map>
 #include "wasi-shim.h"
-#include "godot-wasm.h"
+#include "wasm.h"
 #include "defer.h"
 #include "string-container.h"
 

src/wasi-shim.h

@@ -2,7 +2,7 @@
 #define WASI_SHIM_H
 
 #include <functional>
-#include "wasm.h"
+#include <wasm.h>
 #include "defs.h"
 
 namespace godot {

src/wasm-memory.cpp

@@ -1,4 +1,4 @@
-#include "wasm.h"
+#include <wasm.h>
 #include "wasm-memory.h"
 #include "store.h"
 

src/godot-wasm.cpp → src/wasm.cpp

@@ -1,6 +1,6 @@
 #include <string>
 #include <vector>
-#include "godot-wasm.h"
+#include "wasm.h"
 #include "wasi-shim.h"
 #include "defer.h"
 #include "store.h"
@@ -13,7 +13,7 @@ namespace godot {
     };
 
     struct ContextFuncImport: public ContextExtern {
-      Object* target; // The object from which to invoke callback method
+      ObjectID target; // The ID of the object on which to invoke callback method
       String method; // External name; doesn't necessarily match import name
       std::vector<wasm_valkind_t> results; // Return types
       ContextFuncImport(uint16_t i, const wasm_functype_t* func_type): ContextExtern(i) {
@@ -204,8 +204,9 @@ namespace godot {
       Array params = Array();
       // TODO: Check if args and results match expected sizes
       for (uint16_t i = 0; i < args->size; i++) params.push_back(decode_variant(args->data[i]));
-      // TODO: Ensure target is valid and has method
-      Variant variant = context->target->callv(context->method, params);
+      Object* target = INSTANCE_FROM_ID(context->target);
+      FAIL_IF(target == nullptr, "Failed to retrieve import function target", trap("Failed to retrieve import function target\0"));
+      Variant variant = target->callv(context->method, params);
       godot_error error = extract_results(variant, context, results);
       if (error) FAIL("Extracting import function results failed", trap("Extracting import function results failed\0"));
       return NULL;
@@ -334,9 +335,10 @@ namespace godot {
       const Array& import = dict_safe_get(functions, it.first, Array());
       FAIL_IF(import.size() != 2, "Invalid import function " + it.first, ERR_CANT_CREATE);
       FAIL_IF(import[0].get_type() != Variant::OBJECT, "Invalid import target " + it.first, ERR_CANT_CREATE);
+      FAIL_IF(!INSTANCE_VALIDATE(import[0]), "Invalid import target " + it.first, ERR_CANT_CREATE);
       FAIL_IF(import[1].get_type() != Variant::STRING, "Invalid import method " + it.first, ERR_CANT_CREATE);
       godot_wasm::ContextFuncImport* context = (godot_wasm::ContextFuncImport*)&it.second;
-      context->target = import[0];
+      context->target = import[0].operator Object*()->get_instance_id();
       context->method = import[1];
       extern_map[it.second.index] = wasm_func_as_extern(create_callback(context));
     }

src/godot-wasm.h → src/wasm.h

@@ -2,7 +2,7 @@
 #define GODOT_WASM_H
 
 #include <map>
-#include "wasm.h"
+#include <wasm.h>
 #include "defs.h"
 #include "wasm-memory.h"