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GCC Code Coverage Report

Directory:	./		Exec	Total	Coverage
File:	node_snapshotable.h	Lines:	14	14	100.0 %
Date:	2022-08-16 04:20:39	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)

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
23			enum class EmbedderObjectType : uint8_t {
24			#define V(PropertyName, NativeType) k_##PropertyName,
25			SERIALIZABLE_OBJECT_TYPES(V)
26			#undef V
27			};
28
29			typedef size_t SnapshotIndex;
30
31			// When serializing an embedder object, we'll serialize the native states
32			// into a chunk that can be mapped into a subclass of InternalFieldInfoBase,
33			// and pass it into the V8 callback as the payload of StartupData.
34			// The memory chunk looks like this:
35			//
36			// [ type ] - EmbedderObjectType (a uint8_t)
37			// [ length ] - a size_t
38			// [ ... ] - custom bytes of size \|length - header size\|
39			struct InternalFieldInfoBase {
40			public:
41			EmbedderObjectType type;
42			size_t length;
43
44			template <typename T>
45		24	static T* New(EmbedderObjectType type) {
46			static_assert(std::is_base_of_v<InternalFieldInfoBase, T> \|\|
47			std::is_same_v<InternalFieldInfoBase, T>,
48			"Can only accept InternalFieldInfoBase subclasses");
49		24	void* buf = ::operator new[](sizeof(T));
50		24	T* result = new (buf) T;
51		24	result->type = type;
52		24	result->length = sizeof(T);
53		24	return result;
54			}
55
56			template <typename T>
57		21324	T* Copy() const {
58			static_assert(std::is_base_of_v<InternalFieldInfoBase, T> \|\|
59			std::is_same_v<InternalFieldInfoBase, T>,
60			"Can only accept InternalFieldInfoBase subclasses");
61			static_assert(std::is_trivially_copyable_v<T>,
62			"Can only memcpy trivially copyable class");
63		21324	void* buf = ::operator new[](sizeof(T));
64		21324	T* result = new (buf) T;
65		21324	memcpy(result, this, sizeof(T));
66		21324	return result;
67			}
68
69		21324	void Delete() { ::operator delete[](this); }
70
71			InternalFieldInfoBase() = default;
72			};
73
74			// An interface for snapshotable native objects to inherit from.
75			// Use the SERIALIZABLE_OBJECT_METHODS() macro in the class to define
76			// the following methods to implement:
77			//
78			// - PrepareForSerialization(): This would be run prior to context
79			// serialization. Use this method to e.g. release references that
80			// can be re-initialized, or perform property store operations
81			// that needs a V8 context.
82			// - Serialize(): This would be called during context serialization,
83			// once for each embedder field of the object.
84			// Allocate and construct an InternalFieldInfoBase object that contains
85			// data that can be used to deserialize native states.
86			// - Deserialize(): This would be called after the context is
87			// deserialized and the object graph is complete, once for each
88			// embedder field of the object. Use this to restore native states
89			// in the object.
90			class SnapshotableObject : public BaseObject {
91			public:
92			SnapshotableObject(Environment* env,
93			v8::Local<v8::Object> wrap,
94			EmbedderObjectType type);
95			const char* GetTypeNameChars() const;
96
97			// If returns false, the object will not be serialized.
98			virtual bool PrepareForSerialization(v8::Local<v8::Context> context,
99			v8::SnapshotCreator* creator) = 0;
100			virtual InternalFieldInfoBase* Serialize(int index) = 0;
101		24	bool is_snapshotable() const override { return true; }
102			// We'll make sure that the type is set in the constructor
103		24	EmbedderObjectType type() { return type_; }
104
105			private:
106			EmbedderObjectType type_;
107			};
108
109			#define SERIALIZABLE_OBJECT_METHODS() \
110			bool PrepareForSerialization(v8::Local<v8::Context> context, \
111			v8::SnapshotCreator* creator) override; \
112			InternalFieldInfoBase* Serialize(int index) override; \
113			static void Deserialize(v8::Local<v8::Context> context, \
114			v8::Local<v8::Object> holder, \
115			int index, \
116			InternalFieldInfoBase* info);
117
118			v8::StartupData SerializeNodeContextInternalFields(v8::Local<v8::Object> holder,
119			int index,
120			void* env);
121			void DeserializeNodeInternalFields(v8::Local<v8::Object> holder,
122			int index,
123			v8::StartupData payload,
124			void* env);
125			void SerializeSnapshotableObjects(Environment* env,
126			v8::SnapshotCreator* creator,
127			EnvSerializeInfo* info);
128			} // namespace node
129
130			#endif // defined(NODE_WANT_INTERNALS) && NODE_WANT_INTERNALS
131
132			#endif // SRC_NODE_SNAPSHOTABLE_H_