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GCC Code Coverage Report

Directory:	./		Exec	Total	Coverage
File:	base_object.cc	Lines:	84	86	97.7 %
Date:	2022-12-07 04:23:16	Branches:	51	62	82.3 %


#include "base_object.h"
#include "env-inl.h"
#include "node_realm-inl.h"

namespace node {

using v8::FunctionCallbackInfo;
using v8::FunctionTemplate;
using v8::HandleScope;
using v8::Local;
using v8::Object;
using v8::Value;
using v8::WeakCallbackInfo;
using v8::WeakCallbackType;

BaseObject::BaseObject(Realm* realm, Local<Object> object)
    : persistent_handle_(realm->isolate(), object), realm_(realm) {
  CHECK_EQ(false, object.IsEmpty());
  CHECK_GE(object->InternalFieldCount(), BaseObject::kInternalFieldCount);
  SetInternalFields(object, static_cast<void*>(this));
  realm->AddCleanupHook(DeleteMe, static_cast<void*>(this));
  realm->modify_base_object_count(1);
}

BaseObject::~BaseObject() {
  realm()->modify_base_object_count(-1);
  realm()->RemoveCleanupHook(DeleteMe, static_cast<void*>(this));

  if (UNLIKELY(has_pointer_data())) {
    PointerData* metadata = pointer_data();
    CHECK_EQ(metadata->strong_ptr_count, 0);
    metadata->self = nullptr;
    if (metadata->weak_ptr_count == 0) delete metadata;
  }

  if (persistent_handle_.IsEmpty()) {
    // This most likely happened because the weak callback below cleared it.
    return;
  }

  {
    HandleScope handle_scope(realm()->isolate());
    object()->SetAlignedPointerInInternalField(BaseObject::kSlot, nullptr);
  }
}

void BaseObject::MakeWeak() {
  if (has_pointer_data()) {
    pointer_data()->wants_weak_jsobj = true;
    if (pointer_data()->strong_ptr_count > 0) return;
  }

  persistent_handle_.SetWeak(
      this,
      [](const WeakCallbackInfo<BaseObject>& data) {
        BaseObject* obj = data.GetParameter();
        // Clear the persistent handle so that ~BaseObject() doesn't attempt
        // to mess with internal fields, since the JS object may have
        // transitioned into an invalid state.
        // Refs: https://github.com/nodejs/node/issues/18897
        obj->persistent_handle_.Reset();
        CHECK_IMPLIES(obj->has_pointer_data(),
                      obj->pointer_data()->strong_ptr_count == 0);
        obj->OnGCCollect();
      },
      WeakCallbackType::kParameter);
}

// This just has to be different from the Chromium ones:
// https://source.chromium.org/chromium/chromium/src/+/main:gin/public/gin_embedders.h;l=18-23;drc=5a758a97032f0b656c3c36a3497560762495501a
// Otherwise, when Node is loaded in an isolate which uses cppgc, cppgc will
// misinterpret the data stored in the embedder fields and try to garbage
// collect them.
uint16_t kNodeEmbedderId = 0x90de;

void BaseObject::LazilyInitializedJSTemplateConstructor(
    const FunctionCallbackInfo<Value>& args) {
  DCHECK(args.IsConstructCall());
  CHECK_GE(args.This()->InternalFieldCount(), BaseObject::kInternalFieldCount);
  SetInternalFields(args.This(), nullptr);
}

Local<FunctionTemplate> BaseObject::MakeLazilyInitializedJSTemplate(
    Environment* env) {
  return MakeLazilyInitializedJSTemplate(env->isolate_data());
}

Local<FunctionTemplate> BaseObject::MakeLazilyInitializedJSTemplate(
    IsolateData* isolate_data) {
  Local<FunctionTemplate> t = NewFunctionTemplate(
      isolate_data->isolate(), LazilyInitializedJSTemplateConstructor);
  t->Inherit(BaseObject::GetConstructorTemplate(isolate_data));
  t->InstanceTemplate()->SetInternalFieldCount(BaseObject::kInternalFieldCount);
  return t;
}

BaseObject::PointerData* BaseObject::pointer_data() {
  if (!has_pointer_data()) {
    PointerData* metadata = new PointerData();
    metadata->wants_weak_jsobj = persistent_handle_.IsWeak();
    metadata->self = this;
    pointer_data_ = metadata;
  }
  CHECK(has_pointer_data());
  return pointer_data_;
}

void BaseObject::decrease_refcount() {
  CHECK(has_pointer_data());
  PointerData* metadata = pointer_data();
  CHECK_GT(metadata->strong_ptr_count, 0);
  unsigned int new_refcount = --metadata->strong_ptr_count;
  if (new_refcount == 0) {
    if (metadata->is_detached) {
      OnGCCollect();
    } else if (metadata->wants_weak_jsobj && !persistent_handle_.IsEmpty()) {
      MakeWeak();
    }
  }
}

void BaseObject::increase_refcount() {
  unsigned int prev_refcount = pointer_data()->strong_ptr_count++;
  if (prev_refcount == 0 && !persistent_handle_.IsEmpty())
    persistent_handle_.ClearWeak();
}

void BaseObject::DeleteMe(void* data) {
  BaseObject* self = static_cast<BaseObject*>(data);
  if (self->has_pointer_data() && self->pointer_data()->strong_ptr_count > 0) {
    return self->Detach();
  }
  delete self;
}

bool BaseObject::IsDoneInitializing() const {
  return true;
}

Local<Object> BaseObject::WrappedObject() const {
  return object();
}

bool BaseObject::IsRootNode() const {
  return !persistent_handle_.IsWeak();
}

Local<FunctionTemplate> BaseObject::GetConstructorTemplate(
    IsolateData* isolate_data) {
  Local<FunctionTemplate> tmpl = isolate_data->base_object_ctor_template();
  if (tmpl.IsEmpty()) {
    tmpl = NewFunctionTemplate(isolate_data->isolate(), nullptr);
    tmpl->SetClassName(
        FIXED_ONE_BYTE_STRING(isolate_data->isolate(), "BaseObject"));
    isolate_data->set_base_object_ctor_template(tmpl);
  }
  return tmpl;
}

bool BaseObject::IsNotIndicativeOfMemoryLeakAtExit() const {
  return IsWeakOrDetached();
}

}  // namespace node


Generated by: GCOVR (Version 4.2)

Line	Branch	Exec	Source
1			#include "base_object.h"
2			#include "env-inl.h"
3			#include "node_realm-inl.h"
4
5			namespace node {
6
7			using v8::FunctionCallbackInfo;
8			using v8::FunctionTemplate;
9			using v8::HandleScope;
10			using v8::Local;
11			using v8::Object;
12			using v8::Value;
13			using v8::WeakCallbackInfo;
14			using v8::WeakCallbackType;
15
16		1466227	BaseObject::BaseObject(Realm* realm, Local<Object> object)
17		2932454	: persistent_handle_(realm->isolate(), object), realm_(realm) {
18	✗✓	1466227	CHECK_EQ(false, object.IsEmpty());
19	✗✓	1466227	CHECK_GE(object->InternalFieldCount(), BaseObject::kInternalFieldCount);
20		1466227	SetInternalFields(object, static_cast<void*>(this));
21		1466227	realm->AddCleanupHook(DeleteMe, static_cast<void*>(this));
22		1466227	realm->modify_base_object_count(1);
23		1466227	}
24
25	✓✓✓✓	7959980	BaseObject::~BaseObject() {
26		2900202	realm()->modify_base_object_count(-1);
27		2900202	realm()->RemoveCleanupHook(DeleteMe, static_cast<void*>(this));
28
29	✓✓	2900202	if (UNLIKELY(has_pointer_data())) {
30		395598	PointerData* metadata = pointer_data();
31	✗✓	395598	CHECK_EQ(metadata->strong_ptr_count, 0);
32		395598	metadata->self = nullptr;
33	✓✓	395598	if (metadata->weak_ptr_count == 0) delete metadata;
34			}
35
36	✓✓	2900202	if (persistent_handle_.IsEmpty()) {
37			// This most likely happened because the weak callback below cleared it.
38		2159576	return;
39			}
40
41			{
42		740626	HandleScope handle_scope(realm()->isolate());
43		1481252	object()->SetAlignedPointerInInternalField(BaseObject::kSlot, nullptr);
44			}
45			}
46
47		1329514	void BaseObject::MakeWeak() {
48	✓✓	1329514	if (has_pointer_data()) {
49		44519	pointer_data()->wants_weak_jsobj = true;
50	✓✓	44519	if (pointer_data()->strong_ptr_count > 0) return;
51			}
52
53		2657786	persistent_handle_.SetWeak(
54			this,
55		1079787	[](const WeakCallbackInfo<BaseObject>& data) {
56		1079787	BaseObject* obj = data.GetParameter();
57			// Clear the persistent handle so that ~BaseObject() doesn't attempt
58			// to mess with internal fields, since the JS object may have
59			// transitioned into an invalid state.
60			// Refs: https://github.com/nodejs/node/issues/18897
61		1079787	obj->persistent_handle_.Reset();
62	✓✓✗✓ ✗✓	1079787	CHECK_IMPLIES(obj->has_pointer_data(),
63			obj->pointer_data()->strong_ptr_count == 0);
64		1079787	obj->OnGCCollect();
65		1079787	},
66			WeakCallbackType::kParameter);
67			}
68
69			// This just has to be different from the Chromium ones:
70			// https://source.chromium.org/chromium/chromium/src/+/main:gin/public/gin_embedders.h;l=18-23;drc=5a758a97032f0b656c3c36a3497560762495501a
71			// Otherwise, when Node is loaded in an isolate which uses cppgc, cppgc will
72			// misinterpret the data stored in the embedder fields and try to garbage
73			// collect them.
74			uint16_t kNodeEmbedderId = 0x90de;
75
76		23733	void BaseObject::LazilyInitializedJSTemplateConstructor(
77			const FunctionCallbackInfo<Value>& args) {
78			DCHECK(args.IsConstructCall());
79	✗✓	23733	CHECK_GE(args.This()->InternalFieldCount(), BaseObject::kInternalFieldCount);
80		23733	SetInternalFields(args.This(), nullptr);
81		23733	}
82
83		22225	Local<FunctionTemplate> BaseObject::MakeLazilyInitializedJSTemplate(
84			Environment* env) {
85		22225	return MakeLazilyInitializedJSTemplate(env->isolate_data());
86			}
87
88		23034	Local<FunctionTemplate> BaseObject::MakeLazilyInitializedJSTemplate(
89			IsolateData* isolate_data) {
90			Local<FunctionTemplate> t = NewFunctionTemplate(
91		23034	isolate_data->isolate(), LazilyInitializedJSTemplateConstructor);
92		23034	t->Inherit(BaseObject::GetConstructorTemplate(isolate_data));
93		46068	t->InstanceTemplate()->SetInternalFieldCount(BaseObject::kInternalFieldCount);
94		23034	return t;
95			}
96
97		3401627	BaseObject::PointerData* BaseObject::pointer_data() {
98	✓✓	3401627	if (!has_pointer_data()) {
99		200870	PointerData* metadata = new PointerData();
100		200870	metadata->wants_weak_jsobj = persistent_handle_.IsWeak();
101		200870	metadata->self = this;
102		200870	pointer_data_ = metadata;
103			}
104	✗✓	3401627	CHECK(has_pointer_data());
105		3401627	return pointer_data_;
106			}
107
108		849153	void BaseObject::decrease_refcount() {
109	✗✓	849153	CHECK(has_pointer_data());
110		849153	PointerData* metadata = pointer_data();
111	✗✓	849153	CHECK_GT(metadata->strong_ptr_count, 0);
112		849153	unsigned int new_refcount = --metadata->strong_ptr_count;
113	✓✓	849153	if (new_refcount == 0) {
114	✓✓	265771	if (metadata->is_detached) {
115		191159	OnGCCollect();
116	✓✓✓✗ ✓✓	74612	} else if (metadata->wants_weak_jsobj && !persistent_handle_.IsEmpty()) {
117		43898	MakeWeak();
118			}
119			}
120		849153	}
121
122		852251	void BaseObject::increase_refcount() {
123		852251	unsigned int prev_refcount = pointer_data()->strong_ptr_count++;
124	✓✓✓✓ ✓✓	852251	if (prev_refcount == 0 && !persistent_handle_.IsEmpty())
125		268695	persistent_handle_.ClearWeak();
126		852251	}
127
128		169841	void BaseObject::DeleteMe(void* data) {
129		169841	BaseObject* self = static_cast<BaseObject*>(data);
130	✓✓✓✓ ✓✓	169841	if (self->has_pointer_data() && self->pointer_data()->strong_ptr_count > 0) {
131		904	return self->Detach();
132			}
133	✓✗	168937	delete self;
134			}
135
136		1786	bool BaseObject::IsDoneInitializing() const {
137		1786	return true;
138			}
139
140		976	Local<Object> BaseObject::WrappedObject() const {
141		976	return object();
142			}
143
144		1767	bool BaseObject::IsRootNode() const {
145		3534	return !persistent_handle_.IsWeak();
146			}
147
148		58244	Local<FunctionTemplate> BaseObject::GetConstructorTemplate(
149			IsolateData* isolate_data) {
150		58244	Local<FunctionTemplate> tmpl = isolate_data->base_object_ctor_template();
151	✓✓	58244	if (tmpl.IsEmpty()) {
152		809	tmpl = NewFunctionTemplate(isolate_data->isolate(), nullptr);
153		809	tmpl->SetClassName(
154			FIXED_ONE_BYTE_STRING(isolate_data->isolate(), "BaseObject"));
155		809	isolate_data->set_base_object_ctor_template(tmpl);
156			}
157		58244	return tmpl;
158			}
159
160			bool BaseObject::IsNotIndicativeOfMemoryLeakAtExit() const {
161			return IsWeakOrDetached();
162			}
163
164			} // namespace node