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GCC Code Coverage Report

Directory:	./		Exec	Total	Coverage
File:	node_snapshotable.h	Lines:	14	14	100.0 %
Date:	2022-08-30 04:20:47	Branches:	0	0	- %



#ifndef SRC_NODE_SNAPSHOTABLE_H_
#define SRC_NODE_SNAPSHOTABLE_H_

#if defined(NODE_WANT_INTERNALS) && NODE_WANT_INTERNALS

#include "base_object.h"
#include "util.h"

namespace node {

class Environment;
struct EnvSerializeInfo;
struct SnapshotData;
class ExternalReferenceRegistry;

#define SERIALIZABLE_OBJECT_TYPES(V)                                           \
  V(fs_binding_data, fs::BindingData)                                          \
  V(v8_binding_data, v8_utils::BindingData)                                    \
  V(blob_binding_data, BlobBindingData)                                        \
  V(process_binding_data, process::BindingData)                                \
  V(util_weak_reference, util::WeakReference)

enum class EmbedderObjectType : uint8_t {
#define V(PropertyName, NativeType) k_##PropertyName,
  SERIALIZABLE_OBJECT_TYPES(V)
#undef V
};

typedef size_t SnapshotIndex;

// When serializing an embedder object, we'll serialize the native states
// into a chunk that can be mapped into a subclass of InternalFieldInfoBase,
// and pass it into the V8 callback as the payload of StartupData.
// The memory chunk looks like this:
//
// [   type   ] - EmbedderObjectType (a uint8_t)
// [  length  ] - a size_t
// [    ...   ] - custom bytes of size |length - header size|
struct InternalFieldInfoBase {
 public:
  EmbedderObjectType type;
  size_t length;

  template <typename T>
  static T* New(EmbedderObjectType type) {
    static_assert(std::is_base_of_v<InternalFieldInfoBase, T> ||
                      std::is_same_v<InternalFieldInfoBase, T>,
                  "Can only accept InternalFieldInfoBase subclasses");
    void* buf = ::operator new[](sizeof(T));
    T* result = new (buf) T;
    result->type = type;
    result->length = sizeof(T);
    return result;
  }

  template <typename T>
  T* Copy() const {
    static_assert(std::is_base_of_v<InternalFieldInfoBase, T> ||
                      std::is_same_v<InternalFieldInfoBase, T>,
                  "Can only accept InternalFieldInfoBase subclasses");
    static_assert(std::is_trivially_copyable_v<T>,
                  "Can only memcpy trivially copyable class");
    void* buf = ::operator new[](sizeof(T));
    T* result = new (buf) T;
    memcpy(result, this, sizeof(T));
    return result;
  }

  void Delete() { ::operator delete[](this); }

  InternalFieldInfoBase() = default;
};

// An interface for snapshotable native objects to inherit from.
// Use the SERIALIZABLE_OBJECT_METHODS() macro in the class to define
// the following methods to implement:
//
// - PrepareForSerialization(): This would be run prior to context
//   serialization. Use this method to e.g. release references that
//   can be re-initialized, or perform property store operations
//   that needs a V8 context.
// - Serialize(): This would be called during context serialization,
//   once for each embedder field of the object.
//   Allocate and construct an InternalFieldInfoBase object that contains
//   data that can be used to deserialize native states.
// - Deserialize(): This would be called after the context is
//   deserialized and the object graph is complete, once for each
//   embedder field of the object. Use this to restore native states
//   in the object.
class SnapshotableObject : public BaseObject {
 public:
  SnapshotableObject(Environment* env,
                     v8::Local<v8::Object> wrap,
                     EmbedderObjectType type);
  const char* GetTypeNameChars() const;

  // If returns false, the object will not be serialized.
  virtual bool PrepareForSerialization(v8::Local<v8::Context> context,
                                       v8::SnapshotCreator* creator) = 0;
  virtual InternalFieldInfoBase* Serialize(int index) = 0;
  bool is_snapshotable() const override { return true; }
  // We'll make sure that the type is set in the constructor
  EmbedderObjectType type() { return type_; }

 private:
  EmbedderObjectType type_;
};

#define SERIALIZABLE_OBJECT_METHODS()                                          \
  bool PrepareForSerialization(v8::Local<v8::Context> context,                 \
                               v8::SnapshotCreator* creator) override;         \
  InternalFieldInfoBase* Serialize(int index) override;                        \
  static void Deserialize(v8::Local<v8::Context> context,                      \
                          v8::Local<v8::Object> holder,                        \
                          int index,                                           \
                          InternalFieldInfoBase* info);

v8::StartupData SerializeNodeContextInternalFields(v8::Local<v8::Object> holder,
                                                   int index,
                                                   void* env);
void DeserializeNodeInternalFields(v8::Local<v8::Object> holder,
                                   int index,
                                   v8::StartupData payload,
                                   void* env);
void SerializeSnapshotableObjects(Environment* env,
                                  v8::SnapshotCreator* creator,
                                  EnvSerializeInfo* info);
}  // namespace node

#endif  // defined(NODE_WANT_INTERNALS) && NODE_WANT_INTERNALS

#endif  // SRC_NODE_SNAPSHOTABLE_H_


Generated by: GCOVR (Version 4.2)

Line	Branch	Exec	Source
1
2			#ifndef SRC_NODE_SNAPSHOTABLE_H_
3			#define SRC_NODE_SNAPSHOTABLE_H_
4
5			#if defined(NODE_WANT_INTERNALS) && NODE_WANT_INTERNALS
6
7			#include "base_object.h"
8			#include "util.h"
9
10			namespace node {
11
12			class Environment;
13			struct EnvSerializeInfo;
14			struct SnapshotData;
15			class ExternalReferenceRegistry;
16
17			#define SERIALIZABLE_OBJECT_TYPES(V) \
18			V(fs_binding_data, fs::BindingData) \
19			V(v8_binding_data, v8_utils::BindingData) \
20			V(blob_binding_data, BlobBindingData) \
21			V(process_binding_data, process::BindingData) \
22			V(util_weak_reference, util::WeakReference)
23
24			enum class EmbedderObjectType : uint8_t {
25			#define V(PropertyName, NativeType) k_##PropertyName,
26			SERIALIZABLE_OBJECT_TYPES(V)
27			#undef V
28			};
29
30			typedef size_t SnapshotIndex;
31
32			// When serializing an embedder object, we'll serialize the native states
33			// into a chunk that can be mapped into a subclass of InternalFieldInfoBase,
34			// and pass it into the V8 callback as the payload of StartupData.
35			// The memory chunk looks like this:
36			//
37			// [ type ] - EmbedderObjectType (a uint8_t)
38			// [ length ] - a size_t
39			// [ ... ] - custom bytes of size \|length - header size\|
40			struct InternalFieldInfoBase {
41			public:
42			EmbedderObjectType type;
43			size_t length;
44
45			template <typename T>
46		24	static T* New(EmbedderObjectType type) {
47			static_assert(std::is_base_of_v<InternalFieldInfoBase, T> \|\|
48			std::is_same_v<InternalFieldInfoBase, T>,
49			"Can only accept InternalFieldInfoBase subclasses");
50		24	void* buf = ::operator new[](sizeof(T));
51		24	T* result = new (buf) T;
52		24	result->type = type;
53		24	result->length = sizeof(T);
54		24	return result;
55			}
56
57			template <typename T>
58		43296	T* Copy() const {
59			static_assert(std::is_base_of_v<InternalFieldInfoBase, T> \|\|
60			std::is_same_v<InternalFieldInfoBase, T>,
61			"Can only accept InternalFieldInfoBase subclasses");
62			static_assert(std::is_trivially_copyable_v<T>,
63			"Can only memcpy trivially copyable class");
64		43296	void* buf = ::operator new[](sizeof(T));
65		43296	T* result = new (buf) T;
66		43296	memcpy(result, this, sizeof(T));
67		43296	return result;
68			}
69
70		21644	void Delete() { ::operator delete[](this); }
71
72			InternalFieldInfoBase() = default;
73			};
74
75			// An interface for snapshotable native objects to inherit from.
76			// Use the SERIALIZABLE_OBJECT_METHODS() macro in the class to define
77			// the following methods to implement:
78			//
79			// - PrepareForSerialization(): This would be run prior to context
80			// serialization. Use this method to e.g. release references that
81			// can be re-initialized, or perform property store operations
82			// that needs a V8 context.
83			// - Serialize(): This would be called during context serialization,
84			// once for each embedder field of the object.
85			// Allocate and construct an InternalFieldInfoBase object that contains
86			// data that can be used to deserialize native states.
87			// - Deserialize(): This would be called after the context is
88			// deserialized and the object graph is complete, once for each
89			// embedder field of the object. Use this to restore native states
90			// in the object.
91			class SnapshotableObject : public BaseObject {
92			public:
93			SnapshotableObject(Environment* env,
94			v8::Local<v8::Object> wrap,
95			EmbedderObjectType type);
96			const char* GetTypeNameChars() const;
97
98			// If returns false, the object will not be serialized.
99			virtual bool PrepareForSerialization(v8::Local<v8::Context> context,
100			v8::SnapshotCreator* creator) = 0;
101			virtual InternalFieldInfoBase* Serialize(int index) = 0;
102		24	bool is_snapshotable() const override { return true; }
103			// We'll make sure that the type is set in the constructor
104		24	EmbedderObjectType type() { return type_; }
105
106			private:
107			EmbedderObjectType type_;
108			};
109
110			#define SERIALIZABLE_OBJECT_METHODS() \
111			bool PrepareForSerialization(v8::Local<v8::Context> context, \
112			v8::SnapshotCreator* creator) override; \
113			InternalFieldInfoBase* Serialize(int index) override; \
114			static void Deserialize(v8::Local<v8::Context> context, \
115			v8::Local<v8::Object> holder, \
116			int index, \
117			InternalFieldInfoBase* info);
118
119			v8::StartupData SerializeNodeContextInternalFields(v8::Local<v8::Object> holder,
120			int index,
121			void* env);
122			void DeserializeNodeInternalFields(v8::Local<v8::Object> holder,
123			int index,
124			v8::StartupData payload,
125			void* env);
126			void SerializeSnapshotableObjects(Environment* env,
127			v8::SnapshotCreator* creator,
128			EnvSerializeInfo* info);
129			} // namespace node
130
131			#endif // defined(NODE_WANT_INTERNALS) && NODE_WANT_INTERNALS
132
133			#endif // SRC_NODE_SNAPSHOTABLE_H_