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#include "diagnosticfilename-inl.h"
#include "env-inl.h"
#include "memory_tracker-inl.h"
#include "node_external_reference.h"
#include "stream_base-inl.h"
#include "util-inl.h"
using v8::Array;
using v8::Boolean;
using v8::Context;
using v8::EmbedderGraph;
using v8::EscapableHandleScope;
using v8::FunctionCallbackInfo;
using v8::FunctionTemplate;
using v8::Global;
using v8::HandleScope;
using v8::HeapSnapshot;
using v8::Isolate;
using v8::Local;
using v8::MaybeLocal;
using v8::Number;
using v8::Object;
using v8::ObjectTemplate;
using v8::String;
using v8::Value;
namespace node {
namespace heap {
class JSGraphJSNode : public EmbedderGraph::Node {
public:
const char* Name() override { return "<JS Node>"; }
size_t SizeInBytes() override { return 0; }
bool IsEmbedderNode() override { return false; }
Local<Value> JSValue() { return PersistentToLocal::Strong(persistent_); }
int IdentityHash() {
Local<Value> v = JSValue();
if (v->IsObject()) return v.As<Object>()->GetIdentityHash();
if (v->IsName()) return v.As<v8::Name>()->GetIdentityHash();
if (v->IsInt32()) return v.As<v8::Int32>()->Value();
return 0;
}
JSGraphJSNode(Isolate* isolate, Local<Value> val)
: persistent_(isolate, val) {
CHECK(!val.IsEmpty());
}
struct Hash {
inline size_t operator()(JSGraphJSNode* n) const {
return static_cast<size_t>(n->IdentityHash());
}
};
struct Equal {
inline bool operator()(JSGraphJSNode* a, JSGraphJSNode* b) const {
return a->JSValue()->SameValue(b->JSValue());
}
};
private:
Global<Value> persistent_;
};
class JSGraph : public EmbedderGraph {
public:
explicit JSGraph(Isolate* isolate) : isolate_(isolate) {}
Node* V8Node(const Local<Value>& value) override {
std::unique_ptr<JSGraphJSNode> n { new JSGraphJSNode(isolate_, value) };
auto it = engine_nodes_.find(n.get());
if (it != engine_nodes_.end())
return *it;
engine_nodes_.insert(n.get());
return AddNode(std::unique_ptr<Node>(n.release()));
}
Node* AddNode(std::unique_ptr<Node> node) override {
Node* n = node.get();
nodes_.emplace(std::move(node));
return n;
}
void AddEdge(Node* from, Node* to, const char* name = nullptr) override {
edges_[from].insert(std::make_pair(name, to));
}
MaybeLocal<Array> CreateObject() const {
EscapableHandleScope handle_scope(isolate_);
Local<Context> context = isolate_->GetCurrentContext();
Environment* env = Environment::GetCurrent(context);
std::unordered_map<Node*, Local<Object>> info_objects;
Local<Array> nodes = Array::New(isolate_, nodes_.size());
Local<String> edges_string = FIXED_ONE_BYTE_STRING(isolate_, "edges");
Local<String> is_root_string = FIXED_ONE_BYTE_STRING(isolate_, "isRoot");
Local<String> name_string = env->name_string();
Local<String> size_string = env->size_string();
Local<String> value_string = env->value_string();
Local<String> wraps_string = FIXED_ONE_BYTE_STRING(isolate_, "wraps");
Local<String> to_string = FIXED_ONE_BYTE_STRING(isolate_, "to");
for (const std::unique_ptr<Node>& n : nodes_)
info_objects[n.get()] = Object::New(isolate_);
{
HandleScope handle_scope(isolate_);
size_t i = 0;
for (const std::unique_ptr<Node>& n : nodes_) {
Local<Object> obj = info_objects[n.get()];
Local<Value> value;
std::string name_str;
const char* prefix = n->NamePrefix();
if (prefix == nullptr) {
name_str = n->Name();
} else {
name_str = n->NamePrefix();
name_str += " ";
name_str += n->Name();
}
if (!String::NewFromUtf8(isolate_, name_str.c_str()).ToLocal(&value) ||
obj->Set(context, name_string, value).IsNothing() ||
obj->Set(context,
is_root_string,
Boolean::New(isolate_, n->IsRootNode()))
.IsNothing() ||
obj->Set(
context,
size_string,
Number::New(isolate_, static_cast<double>(n->SizeInBytes())))
.IsNothing() ||
obj->Set(context, edges_string, Array::New(isolate_)).IsNothing()) {
return MaybeLocal<Array>();
}
if (nodes->Set(context, i++, obj).IsNothing())
return MaybeLocal<Array>();
if (!n->IsEmbedderNode()) {
value = static_cast<JSGraphJSNode*>(n.get())->JSValue();
if (obj->Set(context, value_string, value).IsNothing())
return MaybeLocal<Array>();
}
}
}
for (const std::unique_ptr<Node>& n : nodes_) {
Node* wraps = n->WrapperNode();
if (wraps == nullptr) continue;
Local<Object> from = info_objects[n.get()];
Local<Object> to = info_objects[wraps];
if (from->Set(context, wraps_string, to).IsNothing())
return MaybeLocal<Array>();
}
for (const auto& edge_info : edges_) {
Node* source = edge_info.first;
Local<Value> edges;
if (!info_objects[source]->Get(context, edges_string).ToLocal(&edges) ||
!edges->IsArray()) {
return MaybeLocal<Array>();
}
size_t i = 0;
size_t j = 0;
for (const auto& edge : edge_info.second) {
Local<Object> to_object = info_objects[edge.second];
Local<Object> edge_obj = Object::New(isolate_);
Local<Value> edge_name_value;
const char* edge_name = edge.first;
if (edge_name != nullptr) {
if (!String::NewFromUtf8(isolate_, edge_name)
.ToLocal(&edge_name_value)) {
return MaybeLocal<Array>();
}
} else {
edge_name_value = Number::New(isolate_, static_cast<double>(j++));
}
if (edge_obj->Set(context, name_string, edge_name_value).IsNothing() ||
edge_obj->Set(context, to_string, to_object).IsNothing() ||
edges.As<Array>()->Set(context, i++, edge_obj).IsNothing()) {
return MaybeLocal<Array>();
}
}
}
return handle_scope.Escape(nodes);
}
private:
Isolate* isolate_;
std::unordered_set<std::unique_ptr<Node>> nodes_;
std::unordered_set<JSGraphJSNode*, JSGraphJSNode::Hash, JSGraphJSNode::Equal>
engine_nodes_;
std::unordered_map<Node*, std::set<std::pair<const char*, Node*>>> edges_;
};
void BuildEmbedderGraph(const FunctionCallbackInfo<Value>& args) {
Environment* env = Environment::GetCurrent(args);
JSGraph graph(env->isolate());
Environment::BuildEmbedderGraph(env->isolate(), &graph, env);
Local<Array> ret;
if (graph.CreateObject().ToLocal(&ret))
args.GetReturnValue().Set(ret);
}
namespace {
class FileOutputStream : public v8::OutputStream {
public:
explicit FileOutputStream(FILE* stream) : stream_(stream) {}
int GetChunkSize() override {
return 65536; // big chunks == faster
}
void EndOfStream() override {}
WriteResult WriteAsciiChunk(char* data, int size) override {
const size_t len = static_cast<size_t>(size);
size_t off = 0;
while (off < len && !feof(stream_) && !ferror(stream_))
off += fwrite(data + off, 1, len - off, stream_);
return off == len ? kContinue : kAbort;
}
private:
FILE* stream_;
};
class HeapSnapshotStream : public AsyncWrap,
public StreamBase,
public v8::OutputStream {
public:
HeapSnapshotStream(
Environment* env,
HeapSnapshotPointer&& snapshot,
Local<Object> obj) :
AsyncWrap(env, obj, AsyncWrap::PROVIDER_HEAPSNAPSHOT),
StreamBase(env),
snapshot_(std::move(snapshot)) {
MakeWeak();
StreamBase::AttachToObject(GetObject());
}
~HeapSnapshotStream() override {}
int GetChunkSize() override {
return 65536; // big chunks == faster
}
void EndOfStream() override {
EmitRead(UV_EOF);
snapshot_.reset();
}
WriteResult WriteAsciiChunk(char* data, int size) override {
int len = size;
while (len != 0) {
uv_buf_t buf = EmitAlloc(size);
ssize_t avail = len;
if (static_cast<ssize_t>(buf.len) < avail)
avail = buf.len;
memcpy(buf.base, data, avail);
data += avail;
len -= static_cast<int>(avail);
EmitRead(size, buf);
}
return kContinue;
}
int ReadStart() override {
CHECK_NE(snapshot_, nullptr);
snapshot_->Serialize(this, HeapSnapshot::kJSON);
return 0;
}
int ReadStop() override {
return 0;
}
int DoShutdown(ShutdownWrap* req_wrap) override {
UNREACHABLE();
}
int DoWrite(WriteWrap* w,
uv_buf_t* bufs,
size_t count,
uv_stream_t* send_handle) override {
UNREACHABLE();
}
bool IsAlive() override { return snapshot_ != nullptr; }
bool IsClosing() override { return snapshot_ == nullptr; }
AsyncWrap* GetAsyncWrap() override { return this; }
void MemoryInfo(MemoryTracker* tracker) const override {
if (snapshot_ != nullptr) {
tracker->TrackFieldWithSize(
"snapshot", sizeof(*snapshot_), "HeapSnapshot");
}
}
SET_MEMORY_INFO_NAME(HeapSnapshotStream)
SET_SELF_SIZE(HeapSnapshotStream)
private:
HeapSnapshotPointer snapshot_;
};
inline void TakeSnapshot(Environment* env, v8::OutputStream* out) {
HeapSnapshotPointer snapshot {
env->isolate()->GetHeapProfiler()->TakeHeapSnapshot() };
snapshot->Serialize(out, HeapSnapshot::kJSON);
}
} // namespace
bool WriteSnapshot(Environment* env, const char* filename) {
FILE* fp = fopen(filename, "w");
if (fp == nullptr) {
env->ThrowErrnoException(errno, "open");
return false;
}
FileOutputStream stream(fp);
TakeSnapshot(env, &stream);
if (fclose(fp) == EOF) {
env->ThrowErrnoException(errno, "close");
return false;
}
return true;
}
void DeleteHeapSnapshot(const HeapSnapshot* snapshot) {
const_cast<HeapSnapshot*>(snapshot)->Delete();
}
BaseObjectPtr<AsyncWrap> CreateHeapSnapshotStream(
Environment* env, HeapSnapshotPointer&& snapshot) {
HandleScope scope(env->isolate());
if (env->streambaseoutputstream_constructor_template().IsEmpty()) {
// Create FunctionTemplate for HeapSnapshotStream
Local<FunctionTemplate> os = FunctionTemplate::New(env->isolate());
os->Inherit(AsyncWrap::GetConstructorTemplate(env));
Local<ObjectTemplate> ost = os->InstanceTemplate();
ost->SetInternalFieldCount(StreamBase::kInternalFieldCount);
os->SetClassName(
FIXED_ONE_BYTE_STRING(env->isolate(), "HeapSnapshotStream"));
StreamBase::AddMethods(env, os);
env->set_streambaseoutputstream_constructor_template(ost);
}
Local<Object> obj;
if (!env->streambaseoutputstream_constructor_template()
->NewInstance(env->context())
.ToLocal(&obj)) {
return {};
}
return MakeBaseObject<HeapSnapshotStream>(env, std::move(snapshot), obj);
}
void CreateHeapSnapshotStream(const FunctionCallbackInfo<Value>& args) {
Environment* env = Environment::GetCurrent(args);
HeapSnapshotPointer snapshot {
env->isolate()->GetHeapProfiler()->TakeHeapSnapshot() };
CHECK(snapshot);
BaseObjectPtr<AsyncWrap> stream =
CreateHeapSnapshotStream(env, std::move(snapshot));
if (stream)
args.GetReturnValue().Set(stream->object());
}
void TriggerHeapSnapshot(const FunctionCallbackInfo<Value>& args) {
Environment* env = Environment::GetCurrent(args);
Isolate* isolate = args.GetIsolate();
Local<Value> filename_v = args[0];
if (filename_v->IsUndefined()) {
DiagnosticFilename name(env, "Heap", "heapsnapshot");
if (!WriteSnapshot(env, *name))
return;
if (String::NewFromUtf8(isolate, *name).ToLocal(&filename_v)) {
args.GetReturnValue().Set(filename_v);
}
return;
}
BufferValue path(isolate, filename_v);
CHECK_NOT_NULL(*path);
if (!WriteSnapshot(env, *path))
return;
return args.GetReturnValue().Set(filename_v);
}
void Initialize(Local<Object> target,
Local<Value> unused,
Local<Context> context,
void* priv) {
Environment* env = Environment::GetCurrent(context);
env->SetMethod(target, "buildEmbedderGraph", BuildEmbedderGraph);
env->SetMethod(target, "triggerHeapSnapshot", TriggerHeapSnapshot);
env->SetMethod(target, "createHeapSnapshotStream", CreateHeapSnapshotStream);
}
void RegisterExternalReferences(ExternalReferenceRegistry* registry) {
registry->Register(BuildEmbedderGraph);
registry->Register(TriggerHeapSnapshot);
registry->Register(CreateHeapSnapshotStream);
}
} // namespace heap
} // namespace node
NODE_MODULE_CONTEXT_AWARE_INTERNAL(heap_utils, node::heap::Initialize)
NODE_MODULE_EXTERNAL_REFERENCE(heap_utils,
node::heap::RegisterExternalReferences)
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