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GCC Code Coverage Report

Directory:	./		Exec	Total	Coverage
File:	node_wasm_web_api.cc	Lines:	81	94	86.2 %
Date:	2022-04-27 04:15:16	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(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);
}

}  // 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		220	Local<Function> WasmStreamingObject::Initialize(Environment* env) {
22		220	Local<Function> templ = env->wasm_streaming_object_constructor();
23	✓✓	220	if (!templ.IsEmpty()) {
24		213	return templ;
25			}
26
27		7	Local<FunctionTemplate> t = env->NewFunctionTemplate(New);
28		7	t->Inherit(BaseObject::GetConstructorTemplate(env));
29		14	t->InstanceTemplate()->SetInternalFieldCount(
30			WasmStreamingObject::kInternalFieldCount);
31
32		7	env->SetProtoMethod(t, "setURL", SetURL);
33		7	env->SetProtoMethod(t, "push", Push);
34		7	env->SetProtoMethod(t, "finish", Finish);
35		7	env->SetProtoMethod(t, "abort", Abort);
36
37		7	auto function = t->GetFunction(env->context()).ToLocalChecked();
38		7	env->set_wasm_streaming_object_constructor(function);
39		7	return function;
40			}
41
42			void WasmStreamingObject::RegisterExternalReferences(
43			ExternalReferenceRegistry* registry) {
44			registry->Register(Push);
45			registry->Register(Finish);
46			registry->Register(Abort);
47			}
48
49			void WasmStreamingObject::MemoryInfo(MemoryTracker* tracker) const {
50			// v8::WasmStreaming is opaque. We assume that the size of the WebAssembly
51			// module that is being compiled is roughly what V8 allocates (as in, off by
52			// only a small factor).
53			tracker->TrackFieldWithSize("streaming", wasm_size_);
54			}
55
56		220	MaybeLocal<Object> WasmStreamingObject::Create(
57			Environment* env, std::shared_ptr<WasmStreaming> streaming) {
58		220	Local<Function> ctor = Initialize(env);
59			Local<Object> obj;
60	✗✓	440	if (!ctor->NewInstance(env->context(), 0, nullptr).ToLocal(&obj)) {
61			return MaybeLocal<Object>();
62			}
63
64	✗✓	220	CHECK(streaming);
65
66		220	WasmStreamingObject* ptr = Unwrap<WasmStreamingObject>(obj);
67	✗✓	220	CHECK_NOT_NULL(ptr);
68		220	ptr->streaming_ = streaming;
69		220	ptr->wasm_size_ = 0;
70		220	return obj;
71			}
72
73		220	void WasmStreamingObject::New(const FunctionCallbackInfo<Value>& args) {
74	✗✓	220	CHECK(args.IsConstructCall());
75		220	Environment* env = Environment::GetCurrent(args);
76		220	new WasmStreamingObject(env, args.This());
77		220	}
78
79		12	void WasmStreamingObject::SetURL(const FunctionCallbackInfo<Value>& args) {
80			WasmStreamingObject* obj;
81	✗✓	12	ASSIGN_OR_RETURN_UNWRAP(&obj, args.Holder());
82	✗✓	12	CHECK(obj->streaming_);
83
84	✗✓	12	CHECK_EQ(args.Length(), 1);
85	✗✓	24	CHECK(args[0]->IsString());
86		24	Utf8Value url(Environment::GetCurrent(args)->isolate(), args[0]);
87		12	obj->streaming_->SetUrl(url.out(), url.length());
88			}
89
90		348	void WasmStreamingObject::Push(const FunctionCallbackInfo<Value>& args) {
91			WasmStreamingObject* obj;
92	✗✓	348	ASSIGN_OR_RETURN_UNWRAP(&obj, args.Holder());
93	✗✓	348	CHECK(obj->streaming_);
94
95	✗✓	348	CHECK_EQ(args.Length(), 1);
96		348	Local<Value> chunk = args[0];
97
98			// The start of the memory section backing the ArrayBuffer(View), the offset
99			// of the ArrayBuffer(View) within the memory section, and its size in bytes.
100			const void* bytes;
101			size_t offset;
102			size_t size;
103
104	✓✓	348	if (LIKELY(chunk->IsArrayBufferView())) {
105		346	Local<ArrayBufferView> view = chunk.As<ArrayBufferView>();
106		692	bytes = view->Buffer()->GetBackingStore()->Data();
107		346	offset = view->ByteOffset();
108		346	size = view->ByteLength();
109	✓✗	2	} else if (LIKELY(chunk->IsArrayBuffer())) {
110		2	Local<ArrayBuffer> buffer = chunk.As<ArrayBuffer>();
111		2	bytes = buffer->GetBackingStore()->Data();
112		2	offset = 0;
113		2	size = buffer->ByteLength();
114			} else {
115			return node::THROW_ERR_INVALID_ARG_TYPE(
116			Environment::GetCurrent(args),
117			"chunk must be an ArrayBufferView or an ArrayBuffer");
118			}
119
120			// Forward the data to V8. Internally, V8 will make a copy.
121		348	obj->streaming_->OnBytesReceived(static_cast<const uint8_t*>(bytes) + offset,
122			size);
123		348	obj->wasm_size_ += size;
124			}
125
126		146	void WasmStreamingObject::Finish(const FunctionCallbackInfo<Value>& args) {
127			WasmStreamingObject* obj;
128	✗✓	146	ASSIGN_OR_RETURN_UNWRAP(&obj, args.Holder());
129	✗✓	146	CHECK(obj->streaming_);
130
131	✗✓	146	CHECK_EQ(args.Length(), 0);
132		146	obj->streaming_->Finish();
133			}
134
135		74	void WasmStreamingObject::Abort(const FunctionCallbackInfo<Value>& args) {
136			WasmStreamingObject* obj;
137	✗✓	74	ASSIGN_OR_RETURN_UNWRAP(&obj, args.Holder());
138	✗✓	74	CHECK(obj->streaming_);
139
140	✗✓	74	CHECK_EQ(args.Length(), 1);
141		148	obj->streaming_->Abort(args[0]);
142			}
143
144		220	void StartStreamingCompilation(const FunctionCallbackInfo<Value>& info) {
145			// V8 passes an instance of v8::WasmStreaming to this callback, which we can
146			// use to pass the WebAssembly module bytes to V8 as we receive them.
147			// Unfortunately, our fetch() implementation is a JavaScript dependency, so it
148			// is difficult to implement the required logic here. Instead, we create a
149			// a WasmStreamingObject that encapsulates v8::WasmStreaming and that we can
150			// pass to the JavaScript implementation. The JavaScript implementation can
151			// then push() bytes from the Response and eventually either finish() or
152			// abort() the operation.
153
154			// Create the wrapper object.
155			std::shared_ptr<WasmStreaming> streaming =
156		220	WasmStreaming::Unpack(info.GetIsolate(), info.Data());
157		220	Environment* env = Environment::GetCurrent(info);
158			Local<Object> obj;
159	✗✓	440	if (!WasmStreamingObject::Create(env, streaming).ToLocal(&obj)) {
160			// A JavaScript exception is pending. Let V8 deal with it.
161			return;
162			}
163
164			// V8 always passes one argument to this callback.
165	✗✓	220	CHECK_EQ(info.Length(), 1);
166
167			// Prepare the JavaScript implementation for invocation. We will pass the
168			// WasmStreamingObject as the first argument, followed by the argument that we
169			// received from V8, i.e., the first argument passed to compileStreaming (or
170			// instantiateStreaming).
171		220	Local<Function> impl = env->wasm_streaming_compilation_impl();
172	✗✓	220	CHECK(!impl.IsEmpty());
173	✓✗	440	Local<Value> args[] = {obj, info[0]};
174
175			// Hand control to the JavaScript implementation. It should never throw an
176			// error, but if it does, we leave it to the calling V8 code to handle that
177			// gracefully. Otherwise, we assert that the JavaScript function does not
178			// return anything.
179			MaybeLocal<Value> maybe_ret =
180		440	impl->Call(env->context(), info.This(), 2, args);
181			Local<Value> ret;
182	✓✗✗✓ ✗✓	660	CHECK_IMPLIES(maybe_ret.ToLocal(&ret), ret->IsUndefined());
183			}
184
185			// Called once by JavaScript during initialization.
186		5530	void SetImplementation(const FunctionCallbackInfo<Value>& info) {
187		5530	Environment* env = Environment::GetCurrent(info);
188		11060	env->set_wasm_streaming_compilation_impl(info[0].As<Function>());
189		5530	}
190
191		5530	void Initialize(Local<Object> target,
192			Local<Value>,
193			Local<Context> context,
194			void*) {
195		5530	Environment* env = Environment::GetCurrent(context);
196		5530	env->SetMethod(target, "setImplementation", SetImplementation);
197		5530	}
198
199			void RegisterExternalReferences(ExternalReferenceRegistry* registry) {
200			registry->Register(SetImplementation);
201			}
202
203			} // namespace wasm_web_api
204			} // namespace node
205
206		5000	NODE_MODULE_CONTEXT_AWARE_INTERNAL(wasm_web_api, node::wasm_web_api::Initialize)
207			NODE_MODULE_EXTERNAL_REFERENCE(wasm_web_api,
208			node::wasm_web_api::RegisterExternalReferences)