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GCC Code Coverage Report

Directory:	./		Exec	Total	Coverage
File:	node_wasm_web_api.cc	Lines:	93	99	93.9 %
Date:	2022-05-16 04:15:04	Branches:	29	54	53.7 %


#include "node_wasm_web_api.h"

#include "memory_tracker-inl.h"
#include "node_errors.h"

namespace node {
namespace wasm_web_api {

using v8::ArrayBuffer;
using v8::ArrayBufferView;
using v8::Context;
using v8::Function;
using v8::FunctionCallbackInfo;
using v8::FunctionTemplate;
using v8::Local;
using v8::MaybeLocal;
using v8::Object;
using v8::Value;
using v8::WasmStreaming;

Local<Function> WasmStreamingObject::Initialize(Environment* env) {
  Local<Function> templ = env->wasm_streaming_object_constructor();
  if (!templ.IsEmpty()) {
    return templ;
  }

  Local<FunctionTemplate> t = env->NewFunctionTemplate(New);
  t->Inherit(BaseObject::GetConstructorTemplate(env));
  t->InstanceTemplate()->SetInternalFieldCount(
      WasmStreamingObject::kInternalFieldCount);

  env->SetProtoMethod(t, "setURL", SetURL);
  env->SetProtoMethod(t, "push", Push);
  env->SetProtoMethod(t, "finish", Finish);
  env->SetProtoMethod(t, "abort", Abort);

  auto function = t->GetFunction(env->context()).ToLocalChecked();
  env->set_wasm_streaming_object_constructor(function);
  return function;
}

void WasmStreamingObject::RegisterExternalReferences(
    ExternalReferenceRegistry* registry) {
  registry->Register(New);
  registry->Register(Push);
  registry->Register(Finish);
  registry->Register(Abort);
}

void WasmStreamingObject::MemoryInfo(MemoryTracker* tracker) const {
  // v8::WasmStreaming is opaque. We assume that the size of the WebAssembly
  // module that is being compiled is roughly what V8 allocates (as in, off by
  // only a small factor).
  tracker->TrackFieldWithSize("streaming", wasm_size_);
}

MaybeLocal<Object> WasmStreamingObject::Create(
    Environment* env, std::shared_ptr<WasmStreaming> streaming) {
  Local<Function> ctor = Initialize(env);
  Local<Object> obj;
  if (!ctor->NewInstance(env->context(), 0, nullptr).ToLocal(&obj)) {
    return MaybeLocal<Object>();
  }

  CHECK(streaming);

  WasmStreamingObject* ptr = Unwrap<WasmStreamingObject>(obj);
  CHECK_NOT_NULL(ptr);
  ptr->streaming_ = streaming;
  ptr->wasm_size_ = 0;
  return obj;
}

void WasmStreamingObject::New(const FunctionCallbackInfo<Value>& args) {
  CHECK(args.IsConstructCall());
  Environment* env = Environment::GetCurrent(args);
  new WasmStreamingObject(env, args.This());
}

void WasmStreamingObject::SetURL(const FunctionCallbackInfo<Value>& args) {
  WasmStreamingObject* obj;
  ASSIGN_OR_RETURN_UNWRAP(&obj, args.Holder());
  CHECK(obj->streaming_);

  CHECK_EQ(args.Length(), 1);
  CHECK(args[0]->IsString());
  Utf8Value url(Environment::GetCurrent(args)->isolate(), args[0]);
  obj->streaming_->SetUrl(url.out(), url.length());
}

void WasmStreamingObject::Push(const FunctionCallbackInfo<Value>& args) {
  WasmStreamingObject* obj;
  ASSIGN_OR_RETURN_UNWRAP(&obj, args.Holder());
  CHECK(obj->streaming_);

  CHECK_EQ(args.Length(), 1);
  Local<Value> chunk = args[0];

  // The start of the memory section backing the ArrayBuffer(View), the offset
  // of the ArrayBuffer(View) within the memory section, and its size in bytes.
  const void* bytes;
  size_t offset;
  size_t size;

  if (LIKELY(chunk->IsArrayBufferView())) {
    Local<ArrayBufferView> view = chunk.As<ArrayBufferView>();
    bytes = view->Buffer()->GetBackingStore()->Data();
    offset = view->ByteOffset();
    size = view->ByteLength();
  } else if (LIKELY(chunk->IsArrayBuffer())) {
    Local<ArrayBuffer> buffer = chunk.As<ArrayBuffer>();
    bytes = buffer->GetBackingStore()->Data();
    offset = 0;
    size = buffer->ByteLength();
  } else {
    return node::THROW_ERR_INVALID_ARG_TYPE(
        Environment::GetCurrent(args),
        "chunk must be an ArrayBufferView or an ArrayBuffer");
  }

  // Forward the data to V8. Internally, V8 will make a copy.
  obj->streaming_->OnBytesReceived(static_cast<const uint8_t*>(bytes) + offset,
                                   size);
  obj->wasm_size_ += size;
}

void WasmStreamingObject::Finish(const FunctionCallbackInfo<Value>& args) {
  WasmStreamingObject* obj;
  ASSIGN_OR_RETURN_UNWRAP(&obj, args.Holder());
  CHECK(obj->streaming_);

  CHECK_EQ(args.Length(), 0);
  obj->streaming_->Finish();
}

void WasmStreamingObject::Abort(const FunctionCallbackInfo<Value>& args) {
  WasmStreamingObject* obj;
  ASSIGN_OR_RETURN_UNWRAP(&obj, args.Holder());
  CHECK(obj->streaming_);

  CHECK_EQ(args.Length(), 1);
  obj->streaming_->Abort(args[0]);
}

void StartStreamingCompilation(const FunctionCallbackInfo<Value>& info) {
  // V8 passes an instance of v8::WasmStreaming to this callback, which we can
  // use to pass the WebAssembly module bytes to V8 as we receive them.
  // Unfortunately, our fetch() implementation is a JavaScript dependency, so it
  // is difficult to implement the required logic here. Instead, we create a
  // a WasmStreamingObject that encapsulates v8::WasmStreaming and that we can
  // pass to the JavaScript implementation. The JavaScript implementation can
  // then push() bytes from the Response and eventually either finish() or
  // abort() the operation.

  // Create the wrapper object.
  std::shared_ptr<WasmStreaming> streaming =
      WasmStreaming::Unpack(info.GetIsolate(), info.Data());
  Environment* env = Environment::GetCurrent(info);
  Local<Object> obj;
  if (!WasmStreamingObject::Create(env, streaming).ToLocal(&obj)) {
    // A JavaScript exception is pending. Let V8 deal with it.
    return;
  }

  // V8 always passes one argument to this callback.
  CHECK_EQ(info.Length(), 1);

  // Prepare the JavaScript implementation for invocation. We will pass the
  // WasmStreamingObject as the first argument, followed by the argument that we
  // received from V8, i.e., the first argument passed to compileStreaming (or
  // instantiateStreaming).
  Local<Function> impl = env->wasm_streaming_compilation_impl();
  CHECK(!impl.IsEmpty());
  Local<Value> args[] = {obj, info[0]};

  // Hand control to the JavaScript implementation. It should never throw an
  // error, but if it does, we leave it to the calling V8 code to handle that
  // gracefully. Otherwise, we assert that the JavaScript function does not
  // return anything.
  MaybeLocal<Value> maybe_ret =
      impl->Call(env->context(), info.This(), 2, args);
  Local<Value> ret;
  CHECK_IMPLIES(maybe_ret.ToLocal(&ret), ret->IsUndefined());
}

// Called once by JavaScript during initialization.
void SetImplementation(const FunctionCallbackInfo<Value>& info) {
  Environment* env = Environment::GetCurrent(info);
  env->set_wasm_streaming_compilation_impl(info[0].As<Function>());
}

void Initialize(Local<Object> target,
                Local<Value>,
                Local<Context> context,
                void*) {
  Environment* env = Environment::GetCurrent(context);
  env->SetMethod(target, "setImplementation", SetImplementation);
}

void RegisterExternalReferences(ExternalReferenceRegistry* registry) {
  registry->Register(SetImplementation);
  registry->Register(StartStreamingCompilation);
  WasmStreamingObject::RegisterExternalReferences(registry);
}

}  // namespace wasm_web_api
}  // namespace node

NODE_MODULE_CONTEXT_AWARE_INTERNAL(wasm_web_api, node::wasm_web_api::Initialize)
NODE_MODULE_EXTERNAL_REFERENCE(wasm_web_api,
                               node::wasm_web_api::RegisterExternalReferences)


Generated by: GCOVR (Version 4.2)

Line	Branch	Exec	Source
1			#include "node_wasm_web_api.h"
2
3			#include "memory_tracker-inl.h"
4			#include "node_errors.h"
5
6			namespace node {
7			namespace wasm_web_api {
8
9			using v8::ArrayBuffer;
10			using v8::ArrayBufferView;
11			using v8::Context;
12			using v8::Function;
13			using v8::FunctionCallbackInfo;
14			using v8::FunctionTemplate;
15			using v8::Local;
16			using v8::MaybeLocal;
17			using v8::Object;
18			using v8::Value;
19			using v8::WasmStreaming;
20
21		228	Local<Function> WasmStreamingObject::Initialize(Environment* env) {
22		228	Local<Function> templ = env->wasm_streaming_object_constructor();
23	✓✓	228	if (!templ.IsEmpty()) {
24		220	return templ;
25			}
26
27		8	Local<FunctionTemplate> t = env->NewFunctionTemplate(New);
28		8	t->Inherit(BaseObject::GetConstructorTemplate(env));
29		16	t->InstanceTemplate()->SetInternalFieldCount(
30			WasmStreamingObject::kInternalFieldCount);
31
32		8	env->SetProtoMethod(t, "setURL", SetURL);
33		8	env->SetProtoMethod(t, "push", Push);
34		8	env->SetProtoMethod(t, "finish", Finish);
35		8	env->SetProtoMethod(t, "abort", Abort);
36
37		8	auto function = t->GetFunction(env->context()).ToLocalChecked();
38		8	env->set_wasm_streaming_object_constructor(function);
39		8	return function;
40			}
41
42		5180	void WasmStreamingObject::RegisterExternalReferences(
43			ExternalReferenceRegistry* registry) {
44		5180	registry->Register(New);
45		5180	registry->Register(Push);
46		5180	registry->Register(Finish);
47		5180	registry->Register(Abort);
48		5180	}
49
50			void WasmStreamingObject::MemoryInfo(MemoryTracker* tracker) const {
51			// v8::WasmStreaming is opaque. We assume that the size of the WebAssembly
52			// module that is being compiled is roughly what V8 allocates (as in, off by
53			// only a small factor).
54			tracker->TrackFieldWithSize("streaming", wasm_size_);
55			}
56
57		228	MaybeLocal<Object> WasmStreamingObject::Create(
58			Environment* env, std::shared_ptr<WasmStreaming> streaming) {
59		228	Local<Function> ctor = Initialize(env);
60			Local<Object> obj;
61	✗✓	456	if (!ctor->NewInstance(env->context(), 0, nullptr).ToLocal(&obj)) {
62			return MaybeLocal<Object>();
63			}
64
65	✗✓	228	CHECK(streaming);
66
67		228	WasmStreamingObject* ptr = Unwrap<WasmStreamingObject>(obj);
68	✗✓	228	CHECK_NOT_NULL(ptr);
69		228	ptr->streaming_ = streaming;
70		228	ptr->wasm_size_ = 0;
71		228	return obj;
72			}
73
74		228	void WasmStreamingObject::New(const FunctionCallbackInfo<Value>& args) {
75	✗✓	228	CHECK(args.IsConstructCall());
76		228	Environment* env = Environment::GetCurrent(args);
77		228	new WasmStreamingObject(env, args.This());
78		228	}
79
80		12	void WasmStreamingObject::SetURL(const FunctionCallbackInfo<Value>& args) {
81			WasmStreamingObject* obj;
82	✗✓	12	ASSIGN_OR_RETURN_UNWRAP(&obj, args.Holder());
83	✗✓	12	CHECK(obj->streaming_);
84
85	✗✓	12	CHECK_EQ(args.Length(), 1);
86	✗✓	24	CHECK(args[0]->IsString());
87		24	Utf8Value url(Environment::GetCurrent(args)->isolate(), args[0]);
88		12	obj->streaming_->SetUrl(url.out(), url.length());
89			}
90
91		352	void WasmStreamingObject::Push(const FunctionCallbackInfo<Value>& args) {
92			WasmStreamingObject* obj;
93	✗✓	352	ASSIGN_OR_RETURN_UNWRAP(&obj, args.Holder());
94	✗✓	352	CHECK(obj->streaming_);
95
96	✗✓	352	CHECK_EQ(args.Length(), 1);
97		352	Local<Value> chunk = args[0];
98
99			// The start of the memory section backing the ArrayBuffer(View), the offset
100			// of the ArrayBuffer(View) within the memory section, and its size in bytes.
101			const void* bytes;
102			size_t offset;
103			size_t size;
104
105	✓✓	352	if (LIKELY(chunk->IsArrayBufferView())) {
106		350	Local<ArrayBufferView> view = chunk.As<ArrayBufferView>();
107		700	bytes = view->Buffer()->GetBackingStore()->Data();
108		350	offset = view->ByteOffset();
109		350	size = view->ByteLength();
110	✓✗	2	} else if (LIKELY(chunk->IsArrayBuffer())) {
111		2	Local<ArrayBuffer> buffer = chunk.As<ArrayBuffer>();
112		2	bytes = buffer->GetBackingStore()->Data();
113		2	offset = 0;
114		2	size = buffer->ByteLength();
115			} else {
116			return node::THROW_ERR_INVALID_ARG_TYPE(
117			Environment::GetCurrent(args),
118			"chunk must be an ArrayBufferView or an ArrayBuffer");
119			}
120
121			// Forward the data to V8. Internally, V8 will make a copy.
122		352	obj->streaming_->OnBytesReceived(static_cast<const uint8_t*>(bytes) + offset,
123			size);
124		352	obj->wasm_size_ += size;
125			}
126
127		154	void WasmStreamingObject::Finish(const FunctionCallbackInfo<Value>& args) {
128			WasmStreamingObject* obj;
129	✗✓	154	ASSIGN_OR_RETURN_UNWRAP(&obj, args.Holder());
130	✗✓	154	CHECK(obj->streaming_);
131
132	✗✓	154	CHECK_EQ(args.Length(), 0);
133		154	obj->streaming_->Finish();
134			}
135
136		74	void WasmStreamingObject::Abort(const FunctionCallbackInfo<Value>& args) {
137			WasmStreamingObject* obj;
138	✗✓	74	ASSIGN_OR_RETURN_UNWRAP(&obj, args.Holder());
139	✗✓	74	CHECK(obj->streaming_);
140
141	✗✓	74	CHECK_EQ(args.Length(), 1);
142		148	obj->streaming_->Abort(args[0]);
143			}
144
145		228	void StartStreamingCompilation(const FunctionCallbackInfo<Value>& info) {
146			// V8 passes an instance of v8::WasmStreaming to this callback, which we can
147			// use to pass the WebAssembly module bytes to V8 as we receive them.
148			// Unfortunately, our fetch() implementation is a JavaScript dependency, so it
149			// is difficult to implement the required logic here. Instead, we create a
150			// a WasmStreamingObject that encapsulates v8::WasmStreaming and that we can
151			// pass to the JavaScript implementation. The JavaScript implementation can
152			// then push() bytes from the Response and eventually either finish() or
153			// abort() the operation.
154
155			// Create the wrapper object.
156			std::shared_ptr<WasmStreaming> streaming =
157		228	WasmStreaming::Unpack(info.GetIsolate(), info.Data());
158		228	Environment* env = Environment::GetCurrent(info);
159			Local<Object> obj;
160	✗✓	456	if (!WasmStreamingObject::Create(env, streaming).ToLocal(&obj)) {
161			// A JavaScript exception is pending. Let V8 deal with it.
162			return;
163			}
164
165			// V8 always passes one argument to this callback.
166	✗✓	228	CHECK_EQ(info.Length(), 1);
167
168			// Prepare the JavaScript implementation for invocation. We will pass the
169			// WasmStreamingObject as the first argument, followed by the argument that we
170			// received from V8, i.e., the first argument passed to compileStreaming (or
171			// instantiateStreaming).
172		228	Local<Function> impl = env->wasm_streaming_compilation_impl();
173	✗✓	228	CHECK(!impl.IsEmpty());
174	✓✗	456	Local<Value> args[] = {obj, info[0]};
175
176			// Hand control to the JavaScript implementation. It should never throw an
177			// error, but if it does, we leave it to the calling V8 code to handle that
178			// gracefully. Otherwise, we assert that the JavaScript function does not
179			// return anything.
180			MaybeLocal<Value> maybe_ret =
181		456	impl->Call(env->context(), info.This(), 2, args);
182			Local<Value> ret;
183	✓✗✗✓ ✗✓	684	CHECK_IMPLIES(maybe_ret.ToLocal(&ret), ret->IsUndefined());
184			}
185
186			// Called once by JavaScript during initialization.
187		5995	void SetImplementation(const FunctionCallbackInfo<Value>& info) {
188		5995	Environment* env = Environment::GetCurrent(info);
189		11990	env->set_wasm_streaming_compilation_impl(info[0].As<Function>());
190		5995	}
191
192		5995	void Initialize(Local<Object> target,
193			Local<Value>,
194			Local<Context> context,
195			void*) {
196		5995	Environment* env = Environment::GetCurrent(context);
197		5995	env->SetMethod(target, "setImplementation", SetImplementation);
198		5995	}
199
200		5180	void RegisterExternalReferences(ExternalReferenceRegistry* registry) {
201		5180	registry->Register(SetImplementation);
202		5180	registry->Register(StartStreamingCompilation);
203		5180	WasmStreamingObject::RegisterExternalReferences(registry);
204		5180	}
205
206			} // namespace wasm_web_api
207			} // namespace node
208
209		5248	NODE_MODULE_CONTEXT_AWARE_INTERNAL(wasm_web_api, node::wasm_web_api::Initialize)
210		5180	NODE_MODULE_EXTERNAL_REFERENCE(wasm_web_api,
211			node::wasm_web_api::RegisterExternalReferences)