/* * Copyright (c) 2021, Ali Mohammad Pur * Copyright (c) 2023, Tim Flynn * * SPDX-License-Identifier: BSD-2-Clause */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include namespace Web::WebAssembly { static GC::Ref asynchronously_compile_webassembly_module(JS::VM&, ByteBuffer, HTML::Task::Source = HTML::Task::Source::Unspecified); static GC::Ref instantiate_promise_of_module(JS::VM&, GC::Ref, GC::Ptr import_object); static GC::Ref asynchronously_instantiate_webassembly_module(JS::VM&, GC::Ref, GC::Ptr import_object); static GC::Ref compile_potential_webassembly_response(JS::VM&, GC::Ref); namespace Detail { HashMap, WebAssemblyCache> s_caches; WebAssemblyCache& get_cache(JS::Realm& realm) { return s_caches.ensure(realm.global_object()); } } void visit_edges(JS::Object& object, JS::Cell::Visitor& visitor) { auto& global_object = HTML::relevant_global_object(object); if (auto maybe_cache = Detail::s_caches.get(global_object); maybe_cache.has_value()) { auto& cache = maybe_cache.release_value(); visitor.visit(cache.function_instances()); visitor.visit(cache.imported_objects()); visitor.visit(cache.extern_values()); visitor.visit(cache.global_instances()); cache.abstract_machine().visit_external_resources({ .visit_trap = [&visitor](Wasm::ExternallyManagedTrap const& trap) { auto& completion = trap.unsafe_external_object_as(); visitor.visit(completion.value()); } }); } } void finalize(JS::Object& object) { auto& global_object = HTML::relevant_global_object(object); Detail::s_caches.remove(global_object); } // https://webassembly.github.io/spec/js-api/#error-objects void initialize(JS::Object& self, JS::Realm& realm) { // 1. Let namespaceObject be the namespace object. auto& namespace_object = self; // 2. For each error of « "CompileError", "LinkError", "RuntimeError" », // 2.1. Let constructor be a new object, implementing the NativeError Object Structure, with NativeError set to error. // 2.2. ! DefineMethodProperty(namespaceObject, error, constructor, false). // 2..2.2 for error=CompileError: auto descriptor = JS::PropertyDescriptor { .writable = true, .enumerable = false, .configurable = true, }; descriptor.value = &Bindings::ensure_web_constructor(realm, "CompileError"_fly_string); MUST(namespace_object.define_property_or_throw("CompileError"_string, descriptor)); // 2..2.2 for error=LinkError: descriptor.value = &Bindings::ensure_web_constructor(realm, "LinkError"_fly_string); MUST(namespace_object.define_property_or_throw("LinkError"_string, descriptor)); // 2..2.2 for error=RuntimeError: descriptor.value = &Bindings::ensure_web_constructor(realm, "RuntimeError"_fly_string); MUST(namespace_object.define_property_or_throw("RuntimeError"_string, descriptor)); } // https://webassembly.github.io/spec/js-api/#dom-webassembly-validate bool validate(JS::VM& vm, GC::Root& bytes) { // 1. Let stableBytes be a copy of the bytes held by the buffer bytes. auto stable_bytes = WebIDL::get_buffer_source_copy(*bytes->raw_object()); if (stable_bytes.is_error()) { VERIFY(stable_bytes.error().code() == ENOMEM); return false; } // 2. Compile stableBytes as a WebAssembly module and store the results as module. auto module_or_error = Detail::compile_a_webassembly_module(vm, stable_bytes.release_value()); // 3. If module is error, return false. if (module_or_error.is_error()) return false; // 4. Return true. return true; } // https://webassembly.github.io/spec/js-api/#dom-webassembly-compile WebIDL::ExceptionOr> compile(JS::VM& vm, GC::Root& bytes) { auto& realm = *vm.current_realm(); // 1. Let stableBytes be a copy of the bytes held by the buffer bytes. auto stable_bytes = WebIDL::get_buffer_source_copy(*bytes->raw_object()); if (stable_bytes.is_error()) { VERIFY(stable_bytes.error().code() == ENOMEM); return WebIDL::create_rejected_promise_from_exception(realm, vm.throw_completion(vm.error_message(JS::VM::ErrorMessage::OutOfMemory))); } // 2. Asynchronously compile a WebAssembly module from stableBytes and return the result. return asynchronously_compile_webassembly_module(vm, stable_bytes.release_value()); } // https://webassembly.github.io/spec/web-api/index.html#dom-webassembly-compilestreaming WebIDL::ExceptionOr> compile_streaming(JS::VM& vm, GC::Root source) { // The compileStreaming(source) method, when invoked, returns the result of compiling a potential WebAssembly response with source. return compile_potential_webassembly_response(vm, *source); } // https://webassembly.github.io/spec/js-api/#dom-webassembly-instantiate WebIDL::ExceptionOr> instantiate(JS::VM& vm, GC::Root& bytes, Optional>& import_object_handle) { auto& realm = *vm.current_realm(); // 1. Let stableBytes be a copy of the bytes held by the buffer bytes. auto stable_bytes = WebIDL::get_buffer_source_copy(*bytes->raw_object()); if (stable_bytes.is_error()) { VERIFY(stable_bytes.error().code() == ENOMEM); return WebIDL::create_rejected_promise_from_exception(realm, vm.throw_completion(vm.error_message(JS::VM::ErrorMessage::OutOfMemory))); } // 2. Asynchronously compile a WebAssembly module from stableBytes and let promiseOfModule be the result. auto promise_of_module = asynchronously_compile_webassembly_module(vm, stable_bytes.release_value()); // 3. Instantiate promiseOfModule with imports importObject and return the result. GC::Ptr const import_object = import_object_handle.has_value() ? import_object_handle.value().ptr() : nullptr; return instantiate_promise_of_module(vm, promise_of_module, import_object); } // https://webassembly.github.io/spec/js-api/#dom-webassembly-instantiate-moduleobject-importobject WebIDL::ExceptionOr> instantiate(JS::VM& vm, Module const& module_object, Optional>& import_object) { // 1. Asynchronously instantiate the WebAssembly module moduleObject importing importObject, and return the result. GC::Ref module { const_cast(module_object) }; GC::Ptr const imports = import_object.has_value() ? import_object.value().ptr() : nullptr; return asynchronously_instantiate_webassembly_module(vm, module, imports); } // https://webassembly.github.io/spec/web-api/index.html#dom-webassembly-instantiatestreaming WebIDL::ExceptionOr> instantiate_streaming(JS::VM& vm, GC::Root source, Optional>& import_object) { // The instantiateStreaming(source, importObject) method, when invoked, performs the following steps: // 1. Let promiseOfModule be the result of compiling a potential WebAssembly response with source. auto promise_of_module = compile_potential_webassembly_response(vm, *source); // 2. Return the result of instantiating the promise of a module promiseOfModule with imports importObject. auto imports = GC::Ptr { import_object.has_value() ? import_object.value().ptr() : nullptr }; return instantiate_promise_of_module(vm, promise_of_module, imports); } namespace Detail { #define TRY_OR_RETURN_TRAP(...) \ ({ \ /* Ignore -Wshadow to allow nesting the macro. */ \ AK_IGNORE_DIAGNOSTIC("-Wshadow", \ auto&& _temporary_result = (__VA_ARGS__)); \ static_assert(!::AK::Detail::IsLvalueReference, \ "Do not return a reference from a fallible expression"); \ if (_temporary_result.is_error()) [[unlikely]] \ return Wasm::Trap::from_external_object(_temporary_result.release_error()); \ _temporary_result.release_value(); \ }) #define TRY_OR_RETURN_OOM_TRAP(vm, ...) \ ({ \ /* Ignore -Wshadow to allow nesting the macro. */ \ AK_IGNORE_DIAGNOSTIC("-Wshadow", \ auto&& _temporary_result = (__VA_ARGS__)); \ if (_temporary_result.is_error()) { \ VERIFY(_temporary_result.error().code() == ENOMEM); \ return Wasm::Trap::from_external_object((vm).throw_completion((vm).error_message(::JS::VM::ErrorMessage::OutOfMemory))); \ } \ static_assert(!::AK::Detail::IsLvalueReference, \ "Do not return a reference from a fallible expression"); \ _temporary_result.release_value(); \ }) JS::ThrowCompletionOr> instantiate_module(JS::VM& vm, Wasm::Module const& module, GC::Ptr import_object) { Wasm::Linker linker { module }; auto& cache = get_cache(*vm.current_realm()); // https://webassembly.github.io/spec/js-api/index.html#read-the-imports // 1. If module.imports is not empty, and importObject is undefined, throw a TypeError exception. if (!module.import_section().imports().is_empty() && !import_object) { return vm.throw_completion("ImportObject must be provided when module has imports"sv); } // 2. Let imports be « ». HashMap resolved_imports; if (import_object) { dbgln_if(LIBWEB_WASM_DEBUG, "Trying to resolve stuff because import object was specified"); // 3. For each (moduleName, componentName, externtype) of module_imports(module), for (Wasm::Linker::Name const& import_name : linker.unresolved_imports()) { dbgln_if(LIBWEB_WASM_DEBUG, "Trying to resolve {}::{}", import_name.module, import_name.name); // 3.1. Let o be ? Get(importObject, moduleName). auto value_or_error = import_object->get(MUST(String::from_byte_string(import_name.module))); if (value_or_error.is_error()) break; auto value = value_or_error.release_value(); // 3.2. If o is not an Object, throw a TypeError exception. auto object_or_error = value.to_object(vm); if (object_or_error.is_error()) break; auto object = object_or_error.release_value(); // 3.3. Let v be ? Get(o, componentName). auto import_or_error = object->get(MUST(String::from_byte_string(import_name.name))); if (import_or_error.is_error()) break; auto import_ = import_or_error.release_value(); TRY(import_name.type.visit( // 3.4. If externtype is of the form func functype, [&](Wasm::TypeIndex index) -> JS::ThrowCompletionOr { dbgln_if(LIBWEB_WASM_DEBUG, "Trying to resolve a function {}::{}, type index {}", import_name.module, import_name.name, index.value()); auto& type = module.type_section().types()[index.value()]; // FIXME: 3.4.1. If IsCallable(v) is false, throw a LinkError exception. if (!import_.is_function()) return {}; auto& function = import_.as_function(); // 3.4.2. If v has a [[FunctionAddress]] internal slot, and therefore is an Exported Function, Optional address; if (is(function)) { // 3.4.2.1. Let funcaddr be the value of v’s [[FunctionAddress]] internal slot. auto& exported_function = static_cast(function); address = exported_function.exported_address(); } // 3.4.3. Otherwise, else { // 3.4.3.1. Create a host function from v and functype, and let funcaddr be the result. cache.add_imported_object(function); Wasm::HostFunction host_function { [&](auto&, auto& arguments) -> Wasm::Result { GC::RootVector argument_values { vm.heap() }; size_t index = 0; for (auto& entry : arguments) { argument_values.append(to_js_value(vm, entry, type.parameters()[index])); ++index; } auto result = TRY_OR_RETURN_TRAP(JS::call(vm, function, JS::js_undefined(), argument_values.span())); if (type.results().is_empty()) return Wasm::Result { Vector {} }; if (type.results().size() == 1) return Wasm::Result { Vector { TRY_OR_RETURN_TRAP(to_webassembly_value(vm, result, type.results().first())) } }; auto method = TRY_OR_RETURN_TRAP(result.get_method(vm, vm.names.iterator)); if (method == JS::js_undefined()) return Wasm::Trap::from_external_object(vm.throw_completion(JS::ErrorType::NotIterable, result.to_string_without_side_effects())); auto values = TRY_OR_RETURN_TRAP(JS::iterator_to_list(vm, TRY_OR_RETURN_TRAP(JS::get_iterator_from_method(vm, result, *method)))); if (values.size() != type.results().size()) return Wasm::Trap::from_external_object(vm.throw_completion(ByteString::formatted("Invalid number of return values for multi-value wasm return of {} objects", type.results().size()))); Vector wasm_values; TRY_OR_RETURN_OOM_TRAP(vm, wasm_values.try_ensure_capacity(values.size())); size_t i = 0; for (auto& value : values) wasm_values.append(TRY_OR_RETURN_TRAP(to_webassembly_value(vm, value, type.results()[i++]))); return Wasm::Result { move(wasm_values) }; }, type, ByteString::formatted("func{}", resolved_imports.size()), }; address = cache.abstract_machine().store().allocate(move(host_function)); // FIXME: 3.4.3.2. Let index be the number of external functions in imports. This value index is known as the index of the host function funcaddr. // 'index' doesn't seem to be used anywhere? } dbgln_if(LIBWEB_WASM_DEBUG, "Resolved to {}", address->value()); // FIXME: LinkError instead. VERIFY(address.has_value()); // 3.4.4. Let externfunc be the external value func funcaddr. // 3.4.5. Append externfunc to imports. resolved_imports.set(import_name, Wasm::ExternValue { Wasm::FunctionAddress { *address } }); return {}; }, // 3.5. If externtype is of the form global mut valtype, [&](Wasm::GlobalType const& type) -> JS::ThrowCompletionOr { Optional address; // 3.5.1. If v is a Number or v is a BigInt, if (import_.is_number() || import_.is_bigint()) { // 3.5.1.1. If valtype is i64 and v is a Number, if (import_.is_number() && type.type().kind() == Wasm::ValueType::I64) { // 3.5.1.1.1. Throw a LinkError exception. return vm.throw_completion("Import resolution attempted to cast a Number to a BigInteger"sv); } // 3.5.1.2. If valtype is not i64 and v is a BigInt, if (import_.is_bigint() && type.type().kind() != Wasm::ValueType::I64) { // 3.5.1.2.1. Throw a LinkError exception. return vm.throw_completion("Import resolution attempted to cast a BigInteger to a Number"sv); } // 3.5.1.3. If valtype is v128, if (type.type().kind() == Wasm::ValueType::V128) { // 3.5.1.3.1. Throw a LinkError exception. return vm.throw_completion("Import resolution attempted to cast a Number or BigInt to a V128"sv); } // 3.5.1.4. Let value be ToWebAssemblyValue(v, valtype). auto cast_value = TRY(to_webassembly_value(vm, import_, type.type())); // 3.5.1.5. Let store be the surrounding agent's associated store. // 3.5.1.6. Let (store, globaladdr) be global_alloc(store, const valtype, value). // 3.5.1.7. Set the surrounding agent's associated store to store. address = cache.abstract_machine().store().allocate({ type.type(), false }, cast_value); } // FIXME: 3.5.2. Otherwise, if v implements Global, // FIXME: 3.5.2.1. Let globaladdr be v.[[Global]]. // 3.5.3. Otherwise, else { // 3.5.3.1. Throw a LinkError exception. return vm.throw_completion("Invalid value for global type"sv); } // 3.5.4. Let externglobal be global globaladdr. // 3.5.5. Append externglobal to imports. resolved_imports.set(import_name, Wasm::ExternValue { *address }); return {}; }, // 3.6. If externtype is of the form mem memtype, [&](Wasm::MemoryType const&) -> JS::ThrowCompletionOr { // 3.6.1. If v does not implement Memory, throw a LinkError exception. if (!import_.is_object() || !is(import_.as_object())) { return vm.throw_completion("Expected an instance of WebAssembly.Memory for a memory import"sv); } // 3.6.2. Let externmem be the external value mem v.[[Memory]]. auto address = static_cast(import_.as_object()).address(); // 3.6.3. Append externmem to imports. resolved_imports.set(import_name, Wasm::ExternValue { address }); return {}; }, // 3.7. If externtype is of the form table tabletype, [&](Wasm::TableType const&) -> JS::ThrowCompletionOr { // 3.7.1. If v does not implement Table, throw a LinkError exception. if (!import_.is_object() || !is(import_.as_object())) { return vm.throw_completion("Expected an instance of WebAssembly.Table for a table import"sv); } // 3.7.2. Let tableaddr be v.[[Table]]. // 3.7.3. Let externtable be the external value table tableaddr. auto address = static_cast(import_.as_object()).address(); // 3.7.4. Append externtable to imports. resolved_imports.set(import_name, Wasm::ExternValue { address }); return {}; }, [&](auto const&) -> JS::ThrowCompletionOr { // (noop) return {}; })); } } // (inlined) 4. Return imports. linker.link(resolved_imports); auto link_result = linker.finish(); if (link_result.is_error()) { StringBuilder builder; builder.append("Missing "sv); builder.join(' ', link_result.error().missing_imports); return vm.throw_completion(MUST(builder.to_string())); } auto instance_result = cache.abstract_machine().instantiate(module, link_result.release_value()); if (instance_result.is_error()) { return vm.throw_completion(instance_result.error().error); } return instance_result.release_value(); } // // https://webassembly.github.io/spec/js-api/#compile-a-webassembly-module JS::ThrowCompletionOr> compile_a_webassembly_module(JS::VM& vm, ByteBuffer data) { FixedMemoryStream stream { data.bytes() }; auto module_result = Wasm::Module::parse(stream); if (module_result.is_error()) { return vm.throw_completion(Wasm::parse_error_to_byte_string(module_result.error())); } auto& cache = get_cache(*vm.current_realm()); if (auto validation_result = cache.abstract_machine().validate(module_result.value()); validation_result.is_error()) { return vm.throw_completion(validation_result.error().error_string); } auto compiled_module = make_ref_counted(module_result.release_value()); cache.add_compiled_module(compiled_module); return compiled_module; } GC_DEFINE_ALLOCATOR(ExportedWasmFunction); GC::Ref ExportedWasmFunction::create(JS::Realm& realm, FlyString const& name, Function(JS::VM&)> behavior, Wasm::FunctionAddress exported_address) { auto prototype = realm.intrinsics().function_prototype(); return realm.create( name, move(behavior), exported_address, prototype); } ExportedWasmFunction::ExportedWasmFunction(FlyString name, AK::Function(JS::VM&)> behavior, Wasm::FunctionAddress exported_address, JS::Object& prototype) : NativeFunction(move(name), move(behavior), prototype) , m_exported_address(exported_address) { } JS::NativeFunction* create_native_function(JS::VM& vm, Wasm::FunctionAddress address, String const& name, Instance* instance) { auto& realm = *vm.current_realm(); Optional type; auto& cache = get_cache(realm); cache.abstract_machine().store().get(address)->visit([&](auto const& value) { type = value.type(); }); if (auto entry = cache.get_function_instance(address); entry.has_value()) return *entry; auto function = ExportedWasmFunction::create( realm, name, [address, type = type.release_value(), instance](JS::VM& vm) -> JS::ThrowCompletionOr { (void)instance; auto& realm = *vm.current_realm(); Vector values; values.ensure_capacity(type.parameters().size()); // Grab as many values as needed and convert them. size_t index = 0; for (auto& type : type.parameters()) values.append(TRY(to_webassembly_value(vm, vm.argument(index++), type))); auto& cache = get_cache(realm); auto result = cache.abstract_machine().invoke(address, move(values)); // FIXME: Use the convoluted mapping of errors defined in the spec. if (result.is_trap()) { if (auto ptr = result.trap().data.get_pointer()) return ptr->unsafe_external_object_as(); auto& trap = result.trap().data.get(); // https://webassembly.github.io/spec/js-api/#stack-overflow // 6.1. Whenever a stack overflow occurs in WebAssembly code, the same class of exception is thrown as for a stack overflow in JavaScript. if (trap.ends_with(Wasm::Constants::stack_exhaustion_message)) return vm.throw_completion(JS::ErrorType::CallStackSizeExceeded); return vm.throw_completion(TRY_OR_THROW_OOM(vm, String::formatted("Wasm execution trapped (WIP): {}", trap))); } if (result.values().is_empty()) return JS::js_undefined(); if (result.values().size() == 1) return to_js_value(vm, result.values().first(), type.results().first()); // Put result values into a JS::Array in reverse order. auto js_result_values = GC::RootVector { realm.heap() }; js_result_values.ensure_capacity(result.values().size()); for (size_t i = result.values().size(); i > 0; i--) { // Safety: ensure_capacity is called just before this. js_result_values.unchecked_append(to_js_value(vm, result.values().at(i - 1), type.results().at(i - 1))); } return JS::Value(JS::Array::create_from(realm, js_result_values)); }, address); cache.add_function_instance(address, function); return function; } JS::ThrowCompletionOr to_webassembly_value(JS::VM& vm, JS::Value value, Wasm::ValueType const& type) { static ::Crypto::SignedBigInteger two_64 = TRY_OR_THROW_OOM(vm, "1"_sbigint.shift_left(64)); switch (type.kind()) { case Wasm::ValueType::I64: { auto bigint = TRY(value.to_bigint(vm)); auto value = bigint->big_integer().divided_by(two_64).remainder; VERIFY(value.unsigned_value().byte_length() <= sizeof(i64)); i64 integer = static_cast(value.unsigned_value().to_u64()); if (value.is_negative()) integer = -integer; return Wasm::Value { integer }; } case Wasm::ValueType::I32: { auto _i32 = TRY(value.to_i32(vm)); return Wasm::Value { static_cast(_i32) }; } case Wasm::ValueType::F64: { auto number = TRY(value.to_double(vm)); return Wasm::Value { static_cast(number) }; } case Wasm::ValueType::F32: { auto number = TRY(value.to_double(vm)); return Wasm::Value { static_cast(number) }; } case Wasm::ValueType::FunctionReference: { if (value.is_null()) return Wasm::Value(Wasm::ValueType { Wasm::ValueType::Kind::FunctionReference }); if (value.is_function()) { auto& function = value.as_function(); auto& cache = get_cache(*vm.current_realm()); for (auto& entry : cache.function_instances()) { if (entry.value == &function) return Wasm::Value { Wasm::Reference { Wasm::Reference::Func { entry.key, cache.abstract_machine().store().get_module_for(entry.key) } } }; } } return vm.throw_completion(JS::ErrorType::NotAnObjectOfType, "Exported function"); } case Wasm::ValueType::ExternReference: { if (value.is_null()) return Wasm::Value(Wasm::ValueType { Wasm::ValueType::Kind::ExternReference }); auto& cache = get_cache(*vm.current_realm()); for (auto& entry : cache.extern_values()) { if (entry.value == value) return Wasm::Value { Wasm::Reference { Wasm::Reference::Extern { entry.key } } }; } Wasm::ExternAddress extern_addr = cache.extern_values().size(); cache.add_extern_value(extern_addr, value); return Wasm::Value { Wasm::Reference { Wasm::Reference::Extern { extern_addr } } }; } case Wasm::ValueType::V128: return vm.throw_completion("Cannot convert a vector value to a javascript value"sv); } VERIFY_NOT_REACHED(); } Wasm::Value default_webassembly_value(JS::VM& vm, Wasm::ValueType type) { switch (type.kind()) { case Wasm::ValueType::I32: case Wasm::ValueType::I64: case Wasm::ValueType::F32: case Wasm::ValueType::F64: case Wasm::ValueType::V128: case Wasm::ValueType::FunctionReference: return Wasm::Value(type); case Wasm::ValueType::ExternReference: return MUST(to_webassembly_value(vm, JS::js_undefined(), type)); } VERIFY_NOT_REACHED(); } // https://webassembly.github.io/spec/js-api/#tojsvalue JS::Value to_js_value(JS::VM& vm, Wasm::Value& wasm_value, Wasm::ValueType type) { auto& realm = *vm.current_realm(); switch (type.kind()) { case Wasm::ValueType::I64: return realm.create(::Crypto::SignedBigInteger { wasm_value.to() }); case Wasm::ValueType::I32: return JS::Value(wasm_value.to()); case Wasm::ValueType::F64: return JS::Value(wasm_value.to()); case Wasm::ValueType::F32: return JS::Value(static_cast(wasm_value.to())); case Wasm::ValueType::FunctionReference: { auto ref_ = wasm_value.to(); if (ref_.ref().has()) return JS::js_null(); auto address = ref_.ref().get().address; auto& cache = get_cache(realm); auto* function = cache.abstract_machine().store().get(address); auto name = function->visit( [&](Wasm::WasmFunction& wasm_function) { auto index = *wasm_function.module().functions().find_first_index(address); return ByteString::formatted("func{}", index); }, [](Wasm::HostFunction& host_function) { return host_function.name(); }); return create_native_function(vm, address, MUST(String::from_byte_string(name))); } case Wasm::ValueType::ExternReference: { auto ref_ = wasm_value.to(); if (ref_.ref().has()) return JS::js_null(); auto address = ref_.ref().get().address; auto& cache = get_cache(realm); auto value = cache.get_extern_value(address); return value.release_value(); } case Wasm::ValueType::V128: VERIFY_NOT_REACHED(); } VERIFY_NOT_REACHED(); } } // https://webassembly.github.io/spec/js-api/#asynchronously-compile-a-webassembly-module GC::Ref asynchronously_compile_webassembly_module(JS::VM& vm, ByteBuffer bytes, HTML::Task::Source task_source) { auto& realm = *vm.current_realm(); // 1. Let promise be a new Promise. auto promise = WebIDL::create_promise(realm); // 2. Run the following steps in parallel: Platform::EventLoopPlugin::the().deferred_invoke(GC::create_function(vm.heap(), [&vm, &realm, bytes = move(bytes), promise, task_source]() mutable { HTML::TemporaryExecutionContext context(realm, HTML::TemporaryExecutionContext::CallbacksEnabled::Yes); // 1. Compile the WebAssembly module bytes and store the result as module. auto module_or_error = Detail::compile_a_webassembly_module(vm, move(bytes)); // 2. Queue a task to perform the following steps. If taskSource was provided, queue the task on that task source. HTML::queue_a_task(task_source, nullptr, nullptr, GC::create_function(vm.heap(), [&realm, promise, module_or_error = move(module_or_error)]() mutable { HTML::TemporaryExecutionContext context(realm, HTML::TemporaryExecutionContext::CallbacksEnabled::Yes); auto& realm = HTML::relevant_realm(*promise->promise()); // 1. If module is error, reject promise with a CompileError exception. if (module_or_error.is_error()) { WebIDL::reject_promise(realm, promise, module_or_error.error_value()); } // 2. Otherwise, else { // 1. Construct a WebAssembly module object from module and bytes, and let moduleObject be the result. // FIXME: Save bytes to the Module instance instead of moving into compile_a_webassembly_module auto module_object = realm.create(realm, module_or_error.release_value()); // 2. Resolve promise with moduleObject. WebIDL::resolve_promise(realm, promise, module_object); } })); })); // 3. Return promise. return promise; } // https://webassembly.github.io/spec/js-api/#asynchronously-instantiate-a-webassembly-module GC::Ref asynchronously_instantiate_webassembly_module(JS::VM& vm, GC::Ref module_object, GC::Ptr import_object) { auto& realm = *vm.current_realm(); // 1. Let promise be a new promise. auto promise = WebIDL::create_promise(realm); // 2. Let module be moduleObject.[[Module]]. auto module = module_object->compiled_module(); // 3. Read the imports of module with imports importObject, and let imports be the result. // If this operation throws an exception, catch it, reject promise with the exception, and return promise. // Note: We do this at the same time as instantiation in instantiate_module. // 4. Run the following steps in parallel: // 1. Queue a task to perform the following steps: Note: Implementation-specific work may be performed here. HTML::queue_a_task(HTML::Task::Source::Unspecified, nullptr, nullptr, GC::create_function(vm.heap(), [&vm, &realm, promise, module, import_object]() { HTML::TemporaryExecutionContext context(realm, HTML::TemporaryExecutionContext::CallbacksEnabled::Yes); auto& realm = HTML::relevant_realm(*promise->promise()); // 1. Instantiate the core of a WebAssembly module module with imports, and let instance be the result. // If this throws an exception, catch it, reject promise with the exception, and terminate these substeps. auto result = Detail::instantiate_module(vm, module->module, import_object); if (result.is_error()) { WebIDL::reject_promise(realm, promise, result.error_value()); return; } auto instance = result.release_value(); // 2. Let instanceObject be a new Instance. // 3. Initialize instanceObject from module and instance. If this throws an exception, catch it, reject promise with the exception, and terminate these substeps. // FIXME: Investigate whether we are doing all the proper steps for "initialize an instance object" auto instance_object = realm.create(realm, move(instance)); // 4. Resolve promise with instanceObject. WebIDL::resolve_promise(realm, promise, instance_object); })); // 5. Return promise. return promise; } // https://webassembly.github.io/spec/js-api/#instantiate-a-promise-of-a-module GC::Ref instantiate_promise_of_module(JS::VM& vm, GC::Ref promise_of_module, GC::Ptr import_object) { auto& realm = *vm.current_realm(); // 1. Let promise be a new Promise. auto promise = WebIDL::create_promise(realm); // FIXME: Spec should use react to promise here instead of separate upon fulfillment and upon rejection steps // 2. Upon fulfillment of promiseOfModule with value module: auto fulfillment_steps = GC::create_function(vm.heap(), [&vm, promise, import_object](JS::Value module_value) -> WebIDL::ExceptionOr { VERIFY(module_value.is_object() && is(module_value.as_object())); auto module = GC::Ref { static_cast(module_value.as_object()) }; // 1. Instantiate the WebAssembly module module importing importObject, and let innerPromise be the result. auto inner_promise = asynchronously_instantiate_webassembly_module(vm, module, import_object); // 2. Upon fulfillment of innerPromise with value instance. auto instantiate_fulfillment_steps = GC::create_function(vm.heap(), [promise, module](JS::Value instance_value) -> WebIDL::ExceptionOr { auto& realm = HTML::relevant_realm(*promise->promise()); VERIFY(instance_value.is_object() && is(instance_value.as_object())); auto instance = GC::Ref { static_cast(instance_value.as_object()) }; // 1. Let result be the WebAssemblyInstantiatedSource value «[ "module" → module, "instance" → instance ]». auto result = JS::Object::create(realm, nullptr); result->define_direct_property("module"_fly_string, module, JS::default_attributes); result->define_direct_property("instance"_fly_string, instance, JS::default_attributes); // 2. Resolve promise with result. WebIDL::resolve_promise(realm, promise, result); return JS::js_undefined(); }); // 3. Upon rejection of innerPromise with reason reason. auto instantiate_rejection_steps = GC::create_function(vm.heap(), [promise](JS::Value reason) -> WebIDL::ExceptionOr { auto& realm = HTML::relevant_realm(*promise->promise()); // 1. Reject promise with reason. WebIDL::reject_promise(realm, promise, reason); return JS::js_undefined(); }); WebIDL::react_to_promise(inner_promise, instantiate_fulfillment_steps, instantiate_rejection_steps); return JS::js_undefined(); }); // 3. Upon rejection of promiseOfModule with reason reason: auto rejection_steps = GC::create_function(vm.heap(), [promise](JS::Value reason) -> WebIDL::ExceptionOr { auto& realm = HTML::relevant_realm(*promise->promise()); // 1. Reject promise with reason. WebIDL::reject_promise(realm, promise, reason); return JS::js_undefined(); }); WebIDL::react_to_promise(promise_of_module, fulfillment_steps, rejection_steps); // 4. Return promise. return promise; } // https://webassembly.github.io/spec/web-api/index.html#compile-a-potential-webassembly-response GC::Ref compile_potential_webassembly_response(JS::VM& vm, GC::Ref source) { auto& realm = *vm.current_realm(); // Note: This algorithm accepts a Response object, or a promise for one, and compiles and instantiates the resulting bytes of the response. // This compilation can be performed in the background and in a streaming manner. // If the Response is not CORS-same-origin, does not represent an ok status, or does not match the `application/wasm` MIME type, // the returned promise will be rejected with a TypeError; if compilation or instantiation fails, // the returned promise will be rejected with a CompileError or other relevant error type, depending on the cause of failure. // 1. Let returnValue be a new promise auto return_value = WebIDL::create_promise(realm); // 2. Upon fulfillment of source with value unwrappedSource: auto fulfillment_steps = GC::create_function(vm.heap(), [&vm, return_value](JS::Value unwrapped_source) -> WebIDL::ExceptionOr { auto& realm = HTML::relevant_realm(*return_value->promise()); // 1. Let response be unwrappedSource’s response. if (!unwrapped_source.is_object() || !is(unwrapped_source.as_object())) { WebIDL::reject_promise(realm, return_value, vm.throw_completion(JS::ErrorType::NotAnObjectOfType, "Response").value()); return JS::js_undefined(); } auto& response_object = static_cast(unwrapped_source.as_object()); auto response = response_object.response(); // 2. Let mimeType be the result of getting `Content-Type` from response’s header list. // 3. If mimeType is null, reject returnValue with a TypeError and abort these substeps. // 4. Remove all HTTP tab or space byte from the start and end of mimeType. // 5. If mimeType is not a byte-case-insensitive match for `application/wasm`, reject returnValue with a TypeError and abort these substeps. // Note: extra parameters are not allowed, including the empty `application/wasm;`. // FIXME: Validate these extra constraints that are not checked by extract_mime_type() if (auto mime = response->header_list()->extract_mime_type(); !mime.has_value() || mime.value().essence() != "application/wasm"sv) { WebIDL::reject_promise(realm, return_value, vm.throw_completion("Response does not match the application/wasm MIME type"sv).value()); return JS::js_undefined(); } // 6. If response is not CORS-same-origin, reject returnValue with a TypeError and abort these substeps. if (!response->is_cors_same_origin()) { WebIDL::reject_promise(realm, return_value, vm.throw_completion("Response is not CORS-same-origin"sv).value()); return JS::js_undefined(); } // 7. If response’s status is not an ok status, reject returnValue with a TypeError and abort these substeps. if (!response_object.ok()) { WebIDL::reject_promise(realm, return_value, vm.throw_completion("Response does not represent an ok status"sv).value()); return JS::js_undefined(); } // 8. Consume response’s body as an ArrayBuffer, and let bodyPromise be the result. auto body_promise_or_error = response_object.array_buffer(); if (body_promise_or_error.is_error()) { auto throw_completion = Bindings::exception_to_throw_completion(realm.vm(), body_promise_or_error.release_error()); WebIDL::reject_promise(realm, return_value, throw_completion.value()); return JS::js_undefined(); } auto body_promise = body_promise_or_error.release_value(); // 9. Upon fulfillment of bodyPromise with value bodyArrayBuffer: auto body_fulfillment_steps = GC::create_function(vm.heap(), [&vm, return_value](JS::Value body_array_buffer) -> WebIDL::ExceptionOr { // 1. Let stableBytes be a copy of the bytes held by the buffer bodyArrayBuffer. VERIFY(body_array_buffer.is_object()); auto stable_bytes = WebIDL::get_buffer_source_copy(body_array_buffer.as_object()); if (stable_bytes.is_error()) { VERIFY(stable_bytes.error().code() == ENOMEM); WebIDL::reject_promise(HTML::relevant_realm(*return_value->promise()), return_value, vm.throw_completion(vm.error_message(JS::VM::ErrorMessage::OutOfMemory)).value()); return JS::js_undefined(); } // 2. Asynchronously compile the WebAssembly module stableBytes using the networking task source and resolve returnValue with the result. auto result = asynchronously_compile_webassembly_module(vm, stable_bytes.release_value(), HTML::Task::Source::Networking); // Need to manually convert WebIDL promise to an ECMAScript value here to resolve WebIDL::resolve_promise(HTML::relevant_realm(*return_value->promise()), return_value, result->promise()); return JS::js_undefined(); }); // 10. Upon rejection of bodyPromise with reason reason: auto body_rejection_steps = GC::create_function(vm.heap(), [return_value](JS::Value reason) -> WebIDL::ExceptionOr { // 1. Reject returnValue with reason. WebIDL::reject_promise(HTML::relevant_realm(*return_value->promise()), return_value, reason); return JS::js_undefined(); }); WebIDL::react_to_promise(body_promise, body_fulfillment_steps, body_rejection_steps); return JS::js_undefined(); }); // 3. Upon rejection of source with reason reason: auto rejection_steps = GC::create_function(vm.heap(), [return_value](JS::Value reason) -> WebIDL::ExceptionOr { // 1. Reject returnValue with reason. WebIDL::reject_promise(HTML::relevant_realm(*return_value->promise()), return_value, reason); return JS::js_undefined(); }); WebIDL::react_to_promise(source, fulfillment_steps, rejection_steps); // 4. Return returnValue. return return_value; } #define DEFINE_WASM_NATIVE_ERROR(ClassName, snake_name, PrototypeName, ConstructorName) \ GC_DEFINE_ALLOCATOR(ClassName); \ GC::Ref ClassName::create(JS::Realm& realm) \ { \ return realm.create(Bindings::ensure_web_prototype(realm, #ClassName##_fly_string)); \ } \ \ GC::Ref ClassName::create(JS::Realm& realm, String message) \ { \ auto& vm = realm.vm(); \ auto error = ClassName::create(realm); \ u8 const attr = JS::Attribute::Writable | JS::Attribute::Configurable; \ error->define_direct_property(vm.names.message, JS::PrimitiveString::create(vm, move(message)), attr); \ return error; \ } \ \ GC::Ref ClassName::create(JS::Realm& realm, StringView message) \ { \ return create(realm, MUST(String::from_utf8(message))); \ } \ \ ClassName::ClassName(JS::Object& prototype) \ : Error(prototype) \ { \ } DEFINE_WASM_NATIVE_ERROR(CompileError, compile_error, CompileErrorPrototype, CompileErrorConstructor) DEFINE_WASM_NATIVE_ERROR(LinkError, link_error, LinkErrorPrototype, LinkErrorConstructor) DEFINE_WASM_NATIVE_ERROR(RuntimeError, runtime_error, RuntimeErrorPrototype, RuntimeErrorConstructor) #undef DEFINE_WASM_NATIVE_ERROR #define DEFINE_WASM_NATIVE_ERROR_CONSTRUCTOR(ClassName, snake_name, PrototypeName, ConstructorName) \ GC_DEFINE_ALLOCATOR(ConstructorName); \ ConstructorName::ConstructorName(JS::Realm& realm) \ : NativeFunction(#ClassName##_string, *realm.intrinsics().error_constructor()) \ { \ } \ \ void ConstructorName::initialize(JS::Realm& realm) \ { \ auto& vm = this->vm(); \ Base::initialize(realm); \ \ /* 20.5.6.2.1 NativeError.prototype, https://tc39.es/ecma262/#sec-nativeerror.prototype */ \ define_direct_property(vm.names.prototype, &Bindings::ensure_web_prototype(realm, #ClassName##_fly_string), 0); \ \ define_direct_property(vm.names.length, JS::Value(1), JS::Attribute::Configurable); \ } \ \ ConstructorName::~ConstructorName() = default; \ \ /* 20.5.6.1.1 NativeError ( message [ , options ] ), https://tc39.es/ecma262/#sec-nativeerror */ \ JS::ThrowCompletionOr ConstructorName::call() \ { \ /* 1. If NewTarget is undefined, let newTarget be the active function object; else let newTarget be NewTarget. */ \ return TRY(construct(*this)); \ } \ \ /* 20.5.6.1.1 NativeError ( message [ , options ] ), https://tc39.es/ecma262/#sec-nativeerror */ \ JS::ThrowCompletionOr> ConstructorName::construct(JS::FunctionObject& new_target) \ { \ auto& vm = this->vm(); \ \ auto message = vm.argument(0); \ auto options = vm.argument(1); \ \ /* 2. Let O be ? OrdinaryCreateFromConstructor(newTarget, "%NativeError.prototype%", « [[ErrorData]] »). */ \ auto error = TRY(ordinary_create_from_constructor(vm, new_target, &JS::Intrinsics::error_prototype)); \ \ /* 3. If message is not undefined, then */ \ if (!message.is_undefined()) { \ /* a. Let msg be ? ToString(message). */ \ auto msg = TRY(message.to_string(vm)); \ \ /* b. Perform CreateNonEnumerableDataPropertyOrThrow(O, "message", msg). */ \ error->create_non_enumerable_data_property_or_throw(vm.names.message, JS::PrimitiveString::create(vm, move(msg))); \ } \ \ /* 4. Perform ? InstallErrorCause(O, options). */ \ TRY(error->install_error_cause(options)); \ \ /* 5. Return O. */ \ return error; \ } DEFINE_WASM_NATIVE_ERROR_CONSTRUCTOR(CompileError, compile_error, CompileErrorPrototype, CompileErrorConstructor) DEFINE_WASM_NATIVE_ERROR_CONSTRUCTOR(LinkError, link_error, LinkErrorPrototype, LinkErrorConstructor) DEFINE_WASM_NATIVE_ERROR_CONSTRUCTOR(RuntimeError, runtime_error, RuntimeErrorPrototype, RuntimeErrorConstructor) #undef DEFINE_WASM_NATIVE_ERROR_CONSTRUCTOR #define DEFINE_WASM_NATIVE_ERROR_PROTOTYPE(ClassName, snake_name, PrototypeName, ConstructorName) \ GC_DEFINE_ALLOCATOR(PrototypeName); \ \ PrototypeName::PrototypeName(JS::Realm& realm) \ : PrototypeObject(realm.intrinsics().error_prototype()) \ { \ } \ \ void PrototypeName::initialize(JS::Realm& realm) \ { \ auto& vm = this->vm(); \ Base::initialize(realm); \ u8 const attr = JS::Attribute::Writable | JS::Attribute::Configurable; \ define_direct_property(vm.names.name, JS::PrimitiveString::create(vm, #ClassName##_string), attr); \ define_direct_property(vm.names.message, JS::PrimitiveString::create(vm, String {}), attr); \ } DEFINE_WASM_NATIVE_ERROR_PROTOTYPE(CompileError, compile_error, CompileErrorPrototype, CompileErrorConstructor) DEFINE_WASM_NATIVE_ERROR_PROTOTYPE(LinkError, link_error, LinkErrorPrototype, LinkErrorConstructor) DEFINE_WASM_NATIVE_ERROR_PROTOTYPE(RuntimeError, runtime_error, RuntimeErrorPrototype, RuntimeErrorConstructor) #undef DEFINE_WASM_NATIVE_ERROR_PROTOTYPE } #define DEFINE_WASM_ERROR_PROTOTYPE_AND_CONSTRUCTOR_WEB_INTRINSIC(ClassName, snake_name, PrototypeName, ConstructorName) \ template<> \ void Intrinsics::create_web_prototype_and_constructor(JS::Realm & realm) \ { \ auto& vm = realm.vm(); \ auto prototype = heap().allocate(realm); \ m_prototypes.set(#ClassName##_string, prototype); \ \ auto constructor = heap().allocate(realm); \ m_constructors.set(#ClassName##_string, constructor); \ \ prototype->define_direct_property(vm.names.constructor, constructor.ptr(), JS::Attribute::Writable | JS::Attribute::Configurable); \ constructor->define_direct_property(vm.names.name, JS::PrimitiveString::create(vm, #ClassName##_string), JS::Attribute::Configurable); \ } namespace Web::Bindings { DEFINE_WASM_ERROR_PROTOTYPE_AND_CONSTRUCTOR_WEB_INTRINSIC(CompileError, compile_error, CompileErrorPrototype, CompileErrorConstructor) DEFINE_WASM_ERROR_PROTOTYPE_AND_CONSTRUCTOR_WEB_INTRINSIC(LinkError, link_error, LinkErrorPrototype, LinkErrorConstructor) DEFINE_WASM_ERROR_PROTOTYPE_AND_CONSTRUCTOR_WEB_INTRINSIC(RuntimeError, runtime_error, RuntimeErrorPrototype, RuntimeErrorConstructor) } #undef DEFINE_WASM_ERROR_PROTOTYPE_AND_CONSTRUCTOR_WEB_INTRINSIC