OSSForks/node
1
0
Fork 0
mirror of https://github.com/zebrajr/node.git synced 2026-01-15 12:15:26 +00:00
Code Issues Actions 8 Packages Projects Releases Wiki Activity
Files
6f0d104f9dcb6d9f39c43394b4175c58f12f80bb
node/src/node_snapshotable.cc
Chengzhong Wu b8e264d3c3 src: tag v8 aligned pointer slots with embedder data type tags 
PR-URL: https://github.com/nodejs/node/pull/60602
Fixes: https://github.com/nodejs/node/issues/60589
Reviewed-By: Joyee Cheung <joyeec9h3@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Yagiz Nizipli <yagiz@nizipli.com>
Reviewed-By: Juan José Arboleda <soyjuanarbol@gmail.com>
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
2025-11-08 14:27:25 +00:00

1674 lines
58 KiB
C++
Raw Blame History

#include "node_snapshotable.h"
#include <fstream>
#include <iostream>
#include <sstream>
#include <vector>
#include "aliased_buffer-inl.h"
#include "base_object-inl.h"
#include "blob_serializer_deserializer-inl.h"
#include "debug_utils-inl.h"
#include "embedded_data.h"
#include "encoding_binding.h"
#include "env-inl.h"
#include "node_blob.h"
#include "node_builtins.h"
#include "node_contextify.h"
#include "node_errors.h"
#include "node_external_reference.h"
#include "node_file.h"
#include "node_internals.h"
#include "node_main_instance.h"
#include "node_metadata.h"
#include "node_modules.h"
#include "node_process.h"
#include "node_snapshot_builder.h"
#include "node_url.h"
#include "node_v8.h"
#include "node_v8_platform-inl.h"
#include "simdjson.h"
#include "timers.h"
#if HAVE_INSPECTOR
#include "inspector/worker_inspector.h" // ParentInspectorHandle
#endif
namespace node {
using v8::Context;
using v8::Function;
using v8::FunctionCallbackInfo;
using v8::HandleScope;
using v8::Isolate;
using v8::Local;
using v8::LocalVector;
using v8::MaybeLocal;
using v8::Object;
using v8::ObjectTemplate;
using v8::ScriptCompiler;
using v8::ScriptOrigin;
using v8::SnapshotCreator;
using v8::StartupData;
using v8::String;
using v8::TryCatch;
using v8::Value;
const uint32_t SnapshotData::kMagic;
std::ostream& operator<<(std::ostream& output,
const builtins::CodeCacheInfo& info) {
output << "<builtins::CodeCacheInfo id=" << info.id
<< ", length=" << info.data.length << ">\n";
return output;
}
std::ostream& operator<<(std::ostream& output,
const std::vector<builtins::CodeCacheInfo>& vec) {
output << "{\n";
for (const auto& info : vec) {
output << info;
}
output << "}\n";
return output;
}
std::ostream& operator<<(std::ostream& output,
const std::vector<uint8_t>& vec) {
output << "{\n";
for (const auto& i : vec) {
output << i << ",";
}
output << "}";
return output;
}
std::ostream& operator<<(std::ostream& output,
const std::vector<PropInfo>& vec) {
output << "{\n";
for (const auto& info : vec) {
output << " " << info << ",\n";
}
output << "}";
return output;
}
std::ostream& operator<<(std::ostream& output, const PropInfo& info) {
output << "{ \"" << info.name << "\", " << std::to_string(info.id) << ", "
<< std::to_string(info.index) << " }";
return output;
}
std::ostream& operator<<(std::ostream& output,
const std::vector<std::string>& vec) {
output << "{\n";
for (const auto& info : vec) {
output << " \"" << info << "\",\n";
}
output << "}";
return output;
}
std::ostream& operator<<(std::ostream& output, const RealmSerializeInfo& i) {
output << "{\n"
<< "// -- builtins begins --\n"
<< i.builtins << ",\n"
<< "// -- builtins ends --\n"
<< "// -- persistent_values begins --\n"
<< i.persistent_values << ",\n"
<< "// -- persistent_values ends --\n"
<< "// -- native_objects begins --\n"
<< i.native_objects << ",\n"
<< "// -- native_objects ends --\n"
<< i.context << ", // context\n"
<< "}";
return output;
}
std::ostream& operator<<(std::ostream& output, const EnvSerializeInfo& i) {
output << "{\n"
<< "// -- async_hooks begins --\n"
<< i.async_hooks << ",\n"
<< "// -- async_hooks ends --\n"
<< i.tick_info << ", // tick_info\n"
<< i.immediate_info << ", // immediate_info\n"
<< i.timeout_info << ", // timeout_info\n"
<< "// -- performance_state begins --\n"
<< i.performance_state << ",\n"
<< "// -- performance_state ends --\n"
<< i.exit_info << ", // exit_info\n"
<< i.stream_base_state << ", // stream_base_state\n"
<< i.should_abort_on_uncaught_toggle
<< ", // should_abort_on_uncaught_toggle\n"
<< "// -- principal_realm begins --\n"
<< i.principal_realm << ",\n"
<< "// -- principal_realm ends --\n"
<< "}";
return output;
}
class SnapshotDeserializer : public BlobDeserializer<SnapshotDeserializer> {
public:
explicit SnapshotDeserializer(std::string_view v)
: BlobDeserializer<SnapshotDeserializer>(
per_process::enabled_debug_list.enabled(
DebugCategory::SNAPSHOT_SERDES),
v) {}
template <typename T,
std::enable_if_t<!std::is_same<T, std::string>::value>* = nullptr,
std::enable_if_t<!std::is_arithmetic<T>::value>* = nullptr>
T Read();
};
class SnapshotSerializer : public BlobSerializer<SnapshotSerializer> {
public:
SnapshotSerializer()
: BlobSerializer<SnapshotSerializer>(
per_process::enabled_debug_list.enabled(
DebugCategory::SNAPSHOT_SERDES)) {
// Currently the snapshot blob built with an empty script is around 4MB.
// So use that as the default sink size.
sink.reserve(4 * 1024 * 1024);
}
template <typename T,
std::enable_if_t<!std::is_same<T, std::string>::value>* = nullptr,
std::enable_if_t<!std::is_arithmetic<T>::value>* = nullptr>
size_t Write(const T& data);
};
// Layout of v8::StartupData
// [ 4/8 bytes ] raw_size
// [ |raw_size| bytes ] contents
template <>
v8::StartupData SnapshotDeserializer::Read() {
Debug("Read<v8::StartupData>()\n");
int raw_size = ReadArithmetic<int>();
Debug("size=%d\n", raw_size);
CHECK_GT(raw_size, 0); // There should be no startup data of size 0.
// The data pointer of v8::StartupData would be deleted so it must be new'ed.
std::unique_ptr<char> buf = std::unique_ptr<char>(new char[raw_size]);
ReadArithmetic<char>(buf.get(), raw_size);
return v8::StartupData{buf.release(), raw_size};
}
template <>
size_t SnapshotSerializer::Write(const v8::StartupData& data) {
Debug("\nWrite<v8::StartupData>() size=%d\n", data.raw_size);
CHECK_GT(data.raw_size, 0); // There should be no startup data of size 0.
size_t written_total = WriteArithmetic<int>(data.raw_size);
written_total +=
WriteArithmetic<char>(data.data, static_cast<size_t>(data.raw_size));
Debug("Write<v8::StartupData>() wrote %d bytes\n\n", written_total);
return written_total;
}
// Layout of builtins::CodeCacheInfo
// [ 4/8 bytes ] length of the module id string
// [ ... ] |length| bytes of module id
// [ 4/8 bytes ] length of module code cache
// [ ... ] |length| bytes of module code cache
template <>
builtins::CodeCacheInfo SnapshotDeserializer::Read() {
Debug("Read<builtins::CodeCacheInfo>()\n");
std::string id = ReadString();
auto owning_ptr =
std::make_shared<std::vector<uint8_t>>(ReadVector<uint8_t>());
builtins::BuiltinCodeCacheData code_cache_data{std::move(owning_ptr)};
builtins::CodeCacheInfo result{id, code_cache_data};
if (is_debug) {
std::string str = ToStr(result);
Debug("Read<builtins::CodeCacheInfo>() %s\n", str.c_str());
}
return result;
}
template <>
size_t SnapshotSerializer::Write(const builtins::CodeCacheInfo& info) {
Debug("\nWrite<builtins::CodeCacheInfo>() id = %s"
", length=%d\n",
info.id.c_str(),
info.data.length);
size_t written_total = WriteString(info.id);
written_total += WriteArithmetic<size_t>(info.data.length);
written_total += WriteArithmetic(info.data.data, info.data.length);
Debug("Write<builtins::CodeCacheInfo>() wrote %d bytes\n", written_total);
return written_total;
}
// Layout of PropInfo
// [ 4/8 bytes ] length of the data name string
// [ ... ] |length| bytes of data name
// [ 4 bytes ] index in the PropInfo vector
// [ 4/8 bytes ] index in the snapshot blob, can be used with
// GetDataFromSnapshotOnce().
template <>
PropInfo SnapshotDeserializer::Read() {
Debug("Read<PropInfo>()\n");
PropInfo result;
result.name = ReadString();
result.id = ReadArithmetic<uint32_t>();
result.index = ReadArithmetic<SnapshotIndex>();
if (is_debug) {
std::string str = ToStr(result);
Debug("Read<PropInfo>() %s\n", str.c_str());
}
return result;
}
template <>
size_t SnapshotSerializer::Write(const PropInfo& data) {
if (is_debug) {
std::string str = ToStr(data);
Debug("Write<PropInfo>() %s\n", str.c_str());
}
size_t written_total = WriteString(data.name);
written_total += WriteArithmetic<uint32_t>(data.id);
written_total += WriteArithmetic<SnapshotIndex>(data.index);
Debug("Write<PropInfo>() wrote %d bytes\n", written_total);
return written_total;
}
// Layout of AsyncHooks::SerializeInfo
// [ 4/8 bytes ] snapshot index of async_ids_stack
// [ 4/8 bytes ] snapshot index of fields
// [ 4/8 bytes ] snapshot index of async_id_fields
// [ 4/8 bytes ] snapshot index of js_execution_async_resources
// [ 4/8 bytes ] length of native_execution_async_resources
// [ ... ] snapshot indices of each element in
// native_execution_async_resources
template <>
AsyncHooks::SerializeInfo SnapshotDeserializer::Read() {
Debug("Read<AsyncHooks::SerializeInfo>()\n");
AsyncHooks::SerializeInfo result;
result.async_ids_stack = ReadArithmetic<AliasedBufferIndex>();
result.fields = ReadArithmetic<AliasedBufferIndex>();
result.async_id_fields = ReadArithmetic<AliasedBufferIndex>();
result.js_execution_async_resources = ReadArithmetic<SnapshotIndex>();
result.native_execution_async_resources = ReadVector<SnapshotIndex>();
if (is_debug) {
std::string str = ToStr(result);
Debug("Read<AsyncHooks::SerializeInfo>() %s\n", str.c_str());
}
return result;
}
template <>
size_t SnapshotSerializer::Write(const AsyncHooks::SerializeInfo& data) {
if (is_debug) {
std::string str = ToStr(data);
Debug("Write<AsyncHooks::SerializeInfo>() %s\n", str.c_str());
}
size_t written_total =
WriteArithmetic<AliasedBufferIndex>(data.async_ids_stack);
written_total += WriteArithmetic<AliasedBufferIndex>(data.fields);
written_total += WriteArithmetic<AliasedBufferIndex>(data.async_id_fields);
written_total +=
WriteArithmetic<SnapshotIndex>(data.js_execution_async_resources);
written_total +=
WriteVector<SnapshotIndex>(data.native_execution_async_resources);
Debug("Write<AsyncHooks::SerializeInfo>() wrote %d bytes\n", written_total);
return written_total;
}
// Layout of TickInfo::SerializeInfo
// [ 4/8 bytes ] snapshot index of fields
template <>
TickInfo::SerializeInfo SnapshotDeserializer::Read() {
Debug("Read<TickInfo::SerializeInfo>()\n");
TickInfo::SerializeInfo result;
result.fields = ReadArithmetic<AliasedBufferIndex>();
if (is_debug) {
std::string str = ToStr(result);
Debug("Read<TickInfo::SerializeInfo>() %s\n", str.c_str());
}
return result;
}
template <>
size_t SnapshotSerializer::Write(const TickInfo::SerializeInfo& data) {
if (is_debug) {
std::string str = ToStr(data);
Debug("Write<TickInfo::SerializeInfo>() %s\n", str.c_str());
}
size_t written_total = WriteArithmetic<AliasedBufferIndex>(data.fields);
Debug("Write<TickInfo::SerializeInfo>() wrote %d bytes\n", written_total);
return written_total;
}
// Layout of TickInfo::SerializeInfo
// [ 4/8 bytes ] snapshot index of fields
template <>
ImmediateInfo::SerializeInfo SnapshotDeserializer::Read() {
Debug("Read<ImmediateInfo::SerializeInfo>()\n");
ImmediateInfo::SerializeInfo result;
result.fields = ReadArithmetic<AliasedBufferIndex>();
if (is_debug) {
std::string str = ToStr(result);
Debug("Read<ImmediateInfo::SerializeInfo>() %s\n", str.c_str());
}
return result;
}
template <>
size_t SnapshotSerializer::Write(const ImmediateInfo::SerializeInfo& data) {
if (is_debug) {
std::string str = ToStr(data);
Debug("Write<ImmediateInfo::SerializeInfo>() %s\n", str.c_str());
}
size_t written_total = WriteArithmetic<AliasedBufferIndex>(data.fields);
Debug("Write<ImmediateInfo::SerializeInfo>() wrote %d bytes\n",
written_total);
return written_total;
}
// Layout of PerformanceState::SerializeInfo
// [ 4/8 bytes ] snapshot index of root
// [ 4/8 bytes ] snapshot index of milestones
// [ 4/8 bytes ] snapshot index of observers
template <>
performance::PerformanceState::SerializeInfo SnapshotDeserializer::Read() {
Debug("Read<PerformanceState::SerializeInfo>()\n");
performance::PerformanceState::SerializeInfo result;
result.root = ReadArithmetic<AliasedBufferIndex>();
result.milestones = ReadArithmetic<AliasedBufferIndex>();
result.observers = ReadArithmetic<AliasedBufferIndex>();
if (is_debug) {
std::string str = ToStr(result);
Debug("Read<PerformanceState::SerializeInfo>() %s\n", str.c_str());
}
return result;
}
template <>
size_t SnapshotSerializer::Write(
const performance::PerformanceState::SerializeInfo& data) {
if (is_debug) {
std::string str = ToStr(data);
Debug("Write<PerformanceState::SerializeInfo>() %s\n", str.c_str());
}
size_t written_total = WriteArithmetic<AliasedBufferIndex>(data.root);
written_total += WriteArithmetic<AliasedBufferIndex>(data.milestones);
written_total += WriteArithmetic<AliasedBufferIndex>(data.observers);
Debug("Write<PerformanceState::SerializeInfo>() wrote %d bytes\n",
written_total);
return written_total;
}
// Layout of IsolateDataSerializeInfo
// [ 4/8 bytes ] length of primitive_values vector
// [ ... ] |length| of primitive_values indices
// [ 4/8 bytes ] length of template_values vector
// [ ... ] |length| of PropInfo data
template <>
IsolateDataSerializeInfo SnapshotDeserializer::Read() {
Debug("Read<IsolateDataSerializeInfo>()\n");
IsolateDataSerializeInfo result;
result.primitive_values = ReadVector<SnapshotIndex>();
result.template_values = ReadVector<PropInfo>();
if (is_debug) {
std::string str = ToStr(result);
Debug("Read<IsolateDataSerializeInfo>() %s\n", str.c_str());
}
return result;
}
template <>
size_t SnapshotSerializer::Write(const IsolateDataSerializeInfo& data) {
if (is_debug) {
std::string str = ToStr(data);
Debug("Write<IsolateDataSerializeInfo>() %s\n", str.c_str());
}
size_t written_total = WriteVector<SnapshotIndex>(data.primitive_values);
written_total += WriteVector<PropInfo>(data.template_values);
Debug("Write<IsolateDataSerializeInfo>() wrote %d bytes\n", written_total);
return written_total;
}
template <>
RealmSerializeInfo SnapshotDeserializer::Read() {
Debug("Read<RealmSerializeInfo>()\n");
RealmSerializeInfo result;
result.builtins = ReadVector<std::string>();
result.persistent_values = ReadVector<PropInfo>();
result.native_objects = ReadVector<PropInfo>();
result.context = ReadArithmetic<SnapshotIndex>();
return result;
}
template <>
size_t SnapshotSerializer::Write(const RealmSerializeInfo& data) {
if (is_debug) {
std::string str = ToStr(data);
Debug("\nWrite<RealmSerializeInfo>() %s\n", str.c_str());
}
// Use += here to ensure order of evaluation.
size_t written_total = WriteVector<std::string>(data.builtins);
written_total += WriteVector<PropInfo>(data.persistent_values);
written_total += WriteVector<PropInfo>(data.native_objects);
written_total += WriteArithmetic<SnapshotIndex>(data.context);
Debug("Write<RealmSerializeInfo>() wrote %d bytes\n", written_total);
return written_total;
}
template <>
EnvSerializeInfo SnapshotDeserializer::Read() {
Debug("Read<EnvSerializeInfo>()\n");
EnvSerializeInfo result;
result.async_hooks = Read<AsyncHooks::SerializeInfo>();
result.tick_info = Read<TickInfo::SerializeInfo>();
result.immediate_info = Read<ImmediateInfo::SerializeInfo>();
result.timeout_info = ReadArithmetic<AliasedBufferIndex>();
result.performance_state =
Read<performance::PerformanceState::SerializeInfo>();
result.exit_info = ReadArithmetic<AliasedBufferIndex>();
result.stream_base_state = ReadArithmetic<AliasedBufferIndex>();
result.should_abort_on_uncaught_toggle = ReadArithmetic<AliasedBufferIndex>();
result.principal_realm = Read<RealmSerializeInfo>();
return result;
}
template <>
size_t SnapshotSerializer::Write(const EnvSerializeInfo& data) {
if (is_debug) {
std::string str = ToStr(data);
Debug("\nWrite<EnvSerializeInfo>() %s\n", str.c_str());
}
// Use += here to ensure order of evaluation.
size_t written_total = Write<AsyncHooks::SerializeInfo>(data.async_hooks);
written_total += Write<TickInfo::SerializeInfo>(data.tick_info);
written_total += Write<ImmediateInfo::SerializeInfo>(data.immediate_info);
written_total += WriteArithmetic<AliasedBufferIndex>(data.timeout_info);
written_total += Write<performance::PerformanceState::SerializeInfo>(
data.performance_state);
written_total += WriteArithmetic<AliasedBufferIndex>(data.exit_info);
written_total += WriteArithmetic<AliasedBufferIndex>(data.stream_base_state);
written_total +=
WriteArithmetic<AliasedBufferIndex>(data.should_abort_on_uncaught_toggle);
written_total += Write<RealmSerializeInfo>(data.principal_realm);
Debug("Write<EnvSerializeInfo>() wrote %d bytes\n", written_total);
return written_total;
}
// Layout of SnapshotMetadata
// [ 1 byte ] type of the snapshot
// [ 4/8 bytes ] length of the node version string
// [ ... ] |length| bytes of node version
// [ 4/8 bytes ] length of the node arch string
// [ ... ] |length| bytes of node arch
// [ 4/8 bytes ] length of the node platform string
// [ ... ] |length| bytes of node platform
// [ 4 bytes ] v8 cache version tag
template <>
SnapshotMetadata SnapshotDeserializer::Read() {
Debug("Read<SnapshotMetadata>()\n");
SnapshotMetadata result;
result.type = static_cast<SnapshotMetadata::Type>(ReadArithmetic<uint8_t>());
result.node_version = ReadString();
result.node_arch = ReadString();
result.node_platform = ReadString();
result.flags = static_cast<SnapshotFlags>(ReadArithmetic<uint32_t>());
if (is_debug) {
std::string str = ToStr(result);
Debug("Read<SnapshotMetadata>() %s\n", str.c_str());
}
return result;
}
template <>
size_t SnapshotSerializer::Write(const SnapshotMetadata& data) {
if (is_debug) {
std::string str = ToStr(data);
Debug("\nWrite<SnapshotMetadata>() %s\n", str.c_str());
}
size_t written_total = 0;
// We need the Node.js version, platform and arch to match because
// Node.js may perform synchronizations that are platform-specific and they
// can be changed in semver-patches.
Debug("Write snapshot type %d\n", static_cast<uint8_t>(data.type));
written_total += WriteArithmetic<uint8_t>(static_cast<uint8_t>(data.type));
Debug("Write Node.js version %s\n", data.node_version.c_str());
written_total += WriteString(data.node_version);
Debug("Write Node.js arch %s\n", data.node_arch);
written_total += WriteString(data.node_arch);
Debug("Write Node.js platform %s\n", data.node_platform);
written_total += WriteString(data.node_platform);
Debug("Write snapshot flags %" PRIx32 "\n",
static_cast<uint32_t>(data.flags));
written_total += WriteArithmetic<uint32_t>(static_cast<uint32_t>(data.flags));
return written_total;
}
// Layout of the snapshot blob
// [ 4 bytes ] kMagic
// [ 4/8 bytes ] length of Node.js version string
// [ ... ] contents of Node.js version string
// [ 4/8 bytes ] length of Node.js arch string
// [ ... ] contents of Node.js arch string
// [ ... ] v8_snapshot_blob_data from SnapshotCreator::CreateBlob()
// [ ... ] isolate_data_info
// [ ... ] env_info
// [ ... ] code_cache
std::vector<char> SnapshotData::ToBlob() const {
std::vector<char> result;
SnapshotSerializer w;
w.Debug("SnapshotData::ToBlob()\n");
size_t written_total = 0;
// Metadata
w.Debug("0x%x: Write magic %" PRIx32 "\n", w.sink.size(), kMagic);
written_total += w.WriteArithmetic<uint32_t>(kMagic);
w.Debug("0x%x: Write metadata\n", w.sink.size());
written_total += w.Write<SnapshotMetadata>(metadata);
w.Debug("0x%x: Write snapshot blob\n", w.sink.size());
written_total += w.Write<v8::StartupData>(v8_snapshot_blob_data);
w.Debug("0x%x: Write IsolateDataSerializeInfo\n", w.sink.size());
written_total += w.Write<IsolateDataSerializeInfo>(isolate_data_info);
w.Debug("0x%x: Write EnvSerializeInfo\n", w.sink.size());
written_total += w.Write<EnvSerializeInfo>(env_info);
w.Debug("0x%x: Write CodeCacheInfo\n", w.sink.size());
written_total += w.WriteVector<builtins::CodeCacheInfo>(code_cache);
w.Debug("SnapshotData::ToBlob() Wrote %d bytes\n", written_total);
// Return using the temporary value to enable copy elision.
std::swap(result, w.sink);
return result;
}
void SnapshotData::ToFile(FILE* out) const {
const std::vector<char> sink = ToBlob();
size_t num_written = fwrite(sink.data(), sink.size(), 1, out);
CHECK_EQ(num_written, 1);
CHECK_EQ(fflush(out), 0);
}
const SnapshotData* SnapshotData::FromEmbedderWrapper(
const EmbedderSnapshotData* data) {
return data != nullptr ? data->impl_ : nullptr;
}
EmbedderSnapshotData::Pointer SnapshotData::AsEmbedderWrapper() const {
return EmbedderSnapshotData::Pointer{new EmbedderSnapshotData(this, false)};
}
bool SnapshotData::FromFile(SnapshotData* out, FILE* in) {
return FromBlob(out, ReadFileSync(in));
}
bool SnapshotData::FromBlob(SnapshotData* out, const std::vector<char>& in) {
return FromBlob(out, std::string_view(in.data(), in.size()));
}
bool SnapshotData::FromBlob(SnapshotData* out, std::string_view in) {
SnapshotDeserializer r(in);
r.Debug("SnapshotData::FromBlob()\n");
DCHECK_EQ(out->data_ownership, SnapshotData::DataOwnership::kOwned);
// Metadata
uint32_t magic = r.ReadArithmetic<uint32_t>();
r.Debug("Read magic %" PRIx32 "\n", magic);
CHECK_EQ(magic, kMagic);
out->metadata = r.Read<SnapshotMetadata>();
r.Debug("Read metadata\n");
if (!out->Check()) {
return false;
}
out->v8_snapshot_blob_data = r.Read<v8::StartupData>();
r.Debug("Read isolate_data_info\n");
out->isolate_data_info = r.Read<IsolateDataSerializeInfo>();
out->env_info = r.Read<EnvSerializeInfo>();
r.Debug("Read code_cache\n");
out->code_cache = r.ReadVector<builtins::CodeCacheInfo>();
r.Debug("SnapshotData::FromBlob() read %d bytes\n", r.read_total);
return true;
}
bool SnapshotData::Check() const {
if (metadata.node_version != per_process::metadata.versions.node) {
fprintf(stderr,
"Failed to load the startup snapshot because it was built with"
"Node.js version %s and the current Node.js version is %s.\n",
metadata.node_version.c_str(),
NODE_VERSION);
return false;
}
if (metadata.node_arch != per_process::metadata.arch) {
fprintf(stderr,
"Failed to load the startup snapshot because it was built with"
"architecture %s and the architecture is %s.\n",
metadata.node_arch.c_str(),
NODE_ARCH);
return false;
}
if (metadata.node_platform != per_process::metadata.platform) {
fprintf(stderr,
"Failed to load the startup snapshot because it was built with"
"platform %s and the current platform is %s.\n",
metadata.node_platform.c_str(),
NODE_PLATFORM);
return false;
}
// TODO(joyeecheung): check incompatible Node.js flags.
return true;
}
SnapshotData::~SnapshotData() {
if (data_ownership == DataOwnership::kOwned &&
v8_snapshot_blob_data.data != nullptr) {
delete[] v8_snapshot_blob_data.data;
}
}
static std::string GetCodeCacheDefName(const std::string& id) {
char buf[64] = {0};
size_t size = id.size();
CHECK_LT(size, sizeof(buf));
for (size_t i = 0; i < size; ++i) {
char ch = id[i];
buf[i] = (ch == '-' || ch == '/') ? '_' : ch;
}
return std::string(buf) + std::string("_cache_data");
}
static std::string FormatSize(size_t size) {
char buf[64] = {0};
if (size < 1024) {
snprintf(buf, sizeof(buf), "%.2fB", static_cast<double>(size));
} else if (size < 1024 * 1024) {
snprintf(buf, sizeof(buf), "%.2fKB", static_cast<double>(size / 1024));
} else {
snprintf(
buf, sizeof(buf), "%.2fMB", static_cast<double>(size / 1024 / 1024));
}
return buf;
}
template <typename T>
void WriteByteVectorLiteral(std::ostream* ss,
const T* vec,
size_t size,
const char* var_name,
bool use_array_literals) {
constexpr bool is_uint8_t = std::is_same_v<T, uint8_t>;
static_assert(is_uint8_t || std::is_same_v<T, char>);
constexpr const char* type_name = is_uint8_t ? "uint8_t" : "char";
if (!use_array_literals) {
const uint8_t* data = reinterpret_cast<const uint8_t*>(vec);
*ss << "static const " << type_name << " *" << var_name << " = ";
*ss << (is_uint8_t ? R"(reinterpret_cast<const uint8_t *>(")" : "\"");
for (size_t i = 0; i < size; i++) {
const uint8_t ch = data[i];
*ss << GetOctalCode(ch);
if (i % 64 == 63) {
// Go to a newline every 64 bytes since many text editors have
// problems with very long lines.
*ss << "\"\n\"";
}
}
*ss << (is_uint8_t ? "\");\n" : "\";\n");
} else {
*ss << "static const " << type_name << " " << var_name << "[] = {";
for (size_t i = 0; i < size; i++) {
*ss << std::to_string(vec[i]) << (i == size - 1 ? '\n' : ',');
if (i % 64 == 63) {
// Print a newline every 64 units and a offset to improve
// readability.
*ss << " // " << (i / 64) << "\n";
}
}
*ss << "};\n";
}
}
static void WriteCodeCacheInitializer(std::ostream* ss,
const std::string& id,
size_t size) {
std::string def_name = GetCodeCacheDefName(id);
*ss << " { \"" << id << "\",\n";
*ss << " {" << def_name << ",\n";
*ss << " " << size << ",\n";
*ss << " }\n";
*ss << " },\n";
}
void FormatBlob(std::ostream& ss,
const SnapshotData* data,
bool use_array_literals) {
ss << R"(#include <cstddef>
#include "env.h"
#include "node_snapshot_builder.h"
#include "v8.h"
// This file is generated by tools/snapshot. Do not edit.
namespace node {
)";
WriteByteVectorLiteral(&ss,
data->v8_snapshot_blob_data.data,
data->v8_snapshot_blob_data.raw_size,
"v8_snapshot_blob_data",
use_array_literals);
ss << R"(static const int v8_snapshot_blob_size = )"
<< data->v8_snapshot_blob_data.raw_size << ";\n";
// Windows can't deal with too many large vector initializers.
// Store the data into static arrays first.
for (const auto& item : data->code_cache) {
std::string var_name = GetCodeCacheDefName(item.id);
WriteByteVectorLiteral(&ss,
item.data.data,
item.data.length,
var_name.c_str(),
use_array_literals);
}
ss << R"(const SnapshotData snapshot_data {
// -- data_ownership begins --
SnapshotData::DataOwnership::kNotOwned,
// -- data_ownership ends --
// -- metadata begins --
)" << data->metadata
<< R"(,
// -- metadata ends --
// -- v8_snapshot_blob_data begins --
{ v8_snapshot_blob_data, v8_snapshot_blob_size },
// -- v8_snapshot_blob_data ends --
// -- isolate_data_info begins --
)" << data->isolate_data_info
<< R"(
// -- isolate_data_info ends --
,
// -- env_info begins --
)" << data->env_info
<< R"(
// -- env_info ends --
,
// -- code_cache begins --
{)";
for (const auto& item : data->code_cache) {
WriteCodeCacheInitializer(&ss, item.id, item.data.length);
}
ss << R"(
}
// -- code_cache ends --
};
const SnapshotData* SnapshotBuilder::GetEmbeddedSnapshotData() {
return &snapshot_data;
}
} // namespace node
)";
}
// Reset context settings that need to be initialized again after
// deserialization.
static void ResetContextSettingsBeforeSnapshot(Local<Context> context) {
// Reset the AllowCodeGenerationFromStrings flag to true (default value) so
// that it can be re-initialized with v8 flag
// --disallow-code-generation-from-strings and recognized in
// node::InitializeContextRuntime.
context->AllowCodeGenerationFromStrings(true);
}
const std::vector<intptr_t>& SnapshotBuilder::CollectExternalReferences() {
static auto registry = std::make_unique<ExternalReferenceRegistry>();
return registry->external_references();
}
void SnapshotBuilder::InitializeIsolateParams(const SnapshotData* data,
Isolate::CreateParams* params) {
CHECK_NULL(params->snapshot_blob);
if (params->external_references == nullptr) {
params->external_references = CollectExternalReferences().data();
}
params->snapshot_blob =
const_cast<v8::StartupData*>(&(data->v8_snapshot_blob_data));
}
SnapshotFlags operator|(SnapshotFlags x, SnapshotFlags y) {
return static_cast<SnapshotFlags>(static_cast<uint32_t>(x) |
static_cast<uint32_t>(y));
}
SnapshotFlags operator&(SnapshotFlags x, SnapshotFlags y) {
return static_cast<SnapshotFlags>(static_cast<uint32_t>(x) &
static_cast<uint32_t>(y));
}
SnapshotFlags operator|=(/* NOLINT (runtime/references) */ SnapshotFlags& x,
SnapshotFlags y) {
return x = x | y;
}
bool WithoutCodeCache(const SnapshotFlags& flags) {
return static_cast<bool>(flags & SnapshotFlags::kWithoutCodeCache);
}
bool WithoutCodeCache(const SnapshotConfig& config) {
return WithoutCodeCache(config.flags);
}
std::optional<SnapshotConfig> ReadSnapshotConfig(const char* config_path) {
std::string config_content;
int r = ReadFileSync(&config_content, config_path);
if (r != 0) {
FPrintF(stderr,
"Cannot read snapshot configuration from %s: %s\n",
config_path,
uv_strerror(r));
return std::nullopt;
}
SnapshotConfig result;
simdjson::ondemand::parser parser;
simdjson::ondemand::document document;
simdjson::ondemand::object main_object;
simdjson::error_code error =
parser.iterate(simdjson::pad(config_content)).get(document);
if (!error) {
error = document.get_object().get(main_object);
}
if (error) {
FPrintF(stderr,
"Cannot parse JSON from %s: %s\n",
config_path,
simdjson::error_message(error));
return std::nullopt;
}
for (auto field : main_object) {
std::string_view key;
if (field.unescaped_key().get(key)) {
FPrintF(stderr, "Cannot read key from %s\n", config_path);
return std::nullopt;
}
if (key == "builder") {
std::string builder_path;
if (field.value().get_string().get(builder_path) ||
builder_path.empty()) {
FPrintF(stderr,
"\"builder\" field of %s is not a non-empty string\n",
config_path);
return std::nullopt;
}
result.builder_script_path = builder_path;
} else if (key == "withoutCodeCache") {
bool without_code_cache_value = false;
if (field.value().get_bool().get(without_code_cache_value)) {
FPrintF(stderr,
"\"withoutCodeCache\" field of %s is not a boolean\n",
config_path);
return std::nullopt;
}
if (without_code_cache_value) {
result.flags |= SnapshotFlags::kWithoutCodeCache;
}
}
}
if (!result.builder_script_path.has_value()) {
FPrintF(stderr,
"\"builder\" field of %s is not a non-empty string\n",
config_path);
return std::nullopt;
}
return result;
}
ExitCode BuildSnapshotWithoutCodeCache(
SnapshotData* out,
const std::vector<std::string>& args,
const std::vector<std::string>& exec_args,
std::optional<std::string_view> builder_script_content,
const SnapshotConfig& config) {
DCHECK(builder_script_content.has_value() ==
config.builder_script_path.has_value());
// The default snapshot is meant to be runtime-independent and has more
// restrictions. We do not enable the inspector and do not run the event
// loop when building the default snapshot to avoid inconsistencies, but
// we do for the fully customized one, and they are expected to fixup the
// inconsistencies using v8.startupSnapshot callbacks.
SnapshotMetadata::Type snapshot_type =
builder_script_content.has_value()
? SnapshotMetadata::Type::kFullyCustomized
: SnapshotMetadata::Type::kDefault;
std::vector<std::string> errors;
auto setup = CommonEnvironmentSetup::CreateForSnapshotting(
per_process::v8_platform.Platform(), &errors, args, exec_args, config);
if (!setup) {
for (const std::string& err : errors)
fprintf(stderr, "%s: %s\n", args[0].c_str(), err.c_str());
return ExitCode::kBootstrapFailure;
}
Isolate* isolate = setup->isolate();
v8::Locker locker(isolate);
{
HandleScope scope(isolate);
TryCatch bootstrapCatch(isolate);
auto print_Exception = OnScopeLeave([&]() {
if (bootstrapCatch.HasCaught()) {
PrintCaughtException(
isolate, isolate->GetCurrentContext(), bootstrapCatch);
}
});
Context::Scope context_scope(setup->context());
Environment* env = setup->env();
// Run the custom main script for fully customized snapshots.
if (snapshot_type == SnapshotMetadata::Type::kFullyCustomized) {
#if HAVE_INSPECTOR
env->InitializeInspector({});
#endif
if (LoadEnvironment(env, builder_script_content.value()).IsEmpty()) {
return ExitCode::kGenericUserError;
}
}
// Drain the loop and platform tasks before creating a snapshot. This is
// necessary to ensure that the no roots are held by the the platform
// tasks, which may reference objects associated with a context. For
// example, a WeakRef may schedule an per-isolate platform task as a GC
// root, and referencing an object in a context, causing an assertion in
// the snapshot creator.
ExitCode exit_code =
SpinEventLoopInternal(env).FromMaybe(ExitCode::kGenericUserError);
if (exit_code != ExitCode::kNoFailure) {
return exit_code;
}
}
return SnapshotBuilder::CreateSnapshot(out, setup.get());
}
ExitCode BuildCodeCacheFromSnapshot(SnapshotData* out,
const std::vector<std::string>& args,
const std::vector<std::string>& exec_args) {
RAIIIsolate raii_isolate(out);
Isolate* isolate = raii_isolate.get();
v8::Locker locker(isolate);
Isolate::Scope isolate_scope(isolate);
HandleScope handle_scope(isolate);
TryCatch bootstrapCatch(isolate);
auto print_Exception = OnScopeLeave([&]() {
if (bootstrapCatch.HasCaught()) {
PrintCaughtException(
isolate, isolate->GetCurrentContext(), bootstrapCatch);
}
});
Local<Context> context = Context::New(isolate);
Context::Scope context_scope(context);
builtins::BuiltinLoader builtin_loader;
// Regenerate all the code cache.
if (!builtin_loader.CompileAllBuiltinsAndCopyCodeCache(
context,
out->env_info.principal_realm.builtins,
&(out->code_cache))) {
return ExitCode::kGenericUserError;
}
if (per_process::enabled_debug_list.enabled(DebugCategory::MKSNAPSHOT)) {
for (const auto& item : out->code_cache) {
std::string size_str = FormatSize(item.data.length);
per_process::Debug(DebugCategory::MKSNAPSHOT,
"Generated code cache for %d: %s\n",
item.id.c_str(),
size_str.c_str());
}
}
return ExitCode::kNoFailure;
}
ExitCode SnapshotBuilder::Generate(
SnapshotData* out,
const std::vector<std::string>& args,
const std::vector<std::string>& exec_args,
std::optional<std::string_view> builder_script_content,
const SnapshotConfig& snapshot_config) {
ExitCode code = BuildSnapshotWithoutCodeCache(
out, args, exec_args, builder_script_content, snapshot_config);
if (code != ExitCode::kNoFailure) {
return code;
}
if (!WithoutCodeCache(snapshot_config)) {
per_process::Debug(
DebugCategory::CODE_CACHE,
"---\nGenerate code cache to complement snapshot\n---\n");
// Deserialize the snapshot to recompile code cache. We need to do this in
// the second pass because V8 requires the code cache to be compiled with a
// finalized read-only space.
return BuildCodeCacheFromSnapshot(out, args, exec_args);
}
return ExitCode::kNoFailure;
}
ExitCode SnapshotBuilder::CreateSnapshot(SnapshotData* out,
CommonEnvironmentSetup* setup) {
const SnapshotConfig* config = setup->isolate_data()->snapshot_config();
DCHECK_NOT_NULL(config);
SnapshotMetadata::Type snapshot_type =
config->builder_script_path.has_value()
? SnapshotMetadata::Type::kFullyCustomized
: SnapshotMetadata::Type::kDefault;
Isolate* isolate = setup->isolate();
Environment* env = setup->env();
SnapshotCreator* creator = setup->snapshot_creator();
{
HandleScope scope(isolate);
Local<Context> main_context = setup->context();
// The default context with only things created by V8.
Local<Context> default_context = Context::New(isolate);
// The context used by the vm module.
Local<Context> vm_context;
{
Local<ObjectTemplate> global_template =
setup->isolate_data()->contextify_global_template();
CHECK(!global_template.IsEmpty());
if (!contextify::ContextifyContext::CreateV8Context(
isolate, global_template, nullptr, nullptr)
.ToLocal(&vm_context)) {
return ExitCode::kStartupSnapshotFailure;
}
}
// The Node.js-specific context with primodials, can be used by workers
// TODO(joyeecheung): investigate if this can be used by vm contexts
// without breaking compatibility.
Local<Context> base_context = NewContext(isolate);
if (base_context.IsEmpty()) {
return ExitCode::kBootstrapFailure;
}
ResetContextSettingsBeforeSnapshot(base_context);
{
Context::Scope context_scope(main_context);
if (per_process::enabled_debug_list.enabled(DebugCategory::MKSNAPSHOT)) {
env->ForEachRealm([](Realm* realm) { realm->PrintInfoForSnapshot(); });
fprintf(stderr, "Environment = %p\n", env);
}
// Clean up the states left by the inspector because V8 cannot serialize
// them. They don't need to be persisted and can be created from scratch
// after snapshot deserialization.
RunAtExit(env);
#if HAVE_INSPECTOR
env->StopInspector();
#endif
// Serialize the native states
out->isolate_data_info = setup->isolate_data()->Serialize(creator);
out->env_info = env->Serialize(creator);
ResetContextSettingsBeforeSnapshot(main_context);
}
// Global handles to the contexts can't be disposed before the
// blob is created. So initialize all the contexts before adding them.
// TODO(joyeecheung): figure out how to remove this restriction.
creator->SetDefaultContext(default_context);
size_t index = creator->AddContext(vm_context);
CHECK_EQ(index, SnapshotData::kNodeVMContextIndex);
index = creator->AddContext(base_context);
CHECK_EQ(index, SnapshotData::kNodeBaseContextIndex);
index = creator->AddContext(
main_context,
v8::SerializeInternalFieldsCallback(SerializeNodeContextInternalFields,
env),
v8::SerializeContextDataCallback(SerializeNodeContextData, env));
CHECK_EQ(index, SnapshotData::kNodeMainContextIndex);
}
// Must be out of HandleScope
SnapshotCreator::FunctionCodeHandling handling =
WithoutCodeCache(*config) ? SnapshotCreator::FunctionCodeHandling::kClear
: SnapshotCreator::FunctionCodeHandling::kKeep;
out->v8_snapshot_blob_data = creator->CreateBlob(handling);
// We must be able to rehash the blob when we restore it or otherwise
// the hash seed would be fixed by V8, introducing a vulnerability.
if (!out->v8_snapshot_blob_data.CanBeRehashed()) {
return ExitCode::kStartupSnapshotFailure;
}
out->metadata = SnapshotMetadata{snapshot_type,
per_process::metadata.versions.node,
per_process::metadata.arch,
per_process::metadata.platform,
config->flags};
// We cannot resurrect the handles from the snapshot, so make sure that
// no handles are left open in the environment after the blob is created
// (which should trigger a GC and close all handles that can be closed).
bool queues_are_empty =
env->req_wrap_queue()->IsEmpty() && env->handle_wrap_queue()->IsEmpty();
if (!queues_are_empty ||
per_process::enabled_debug_list.enabled(DebugCategory::MKSNAPSHOT)) {
PrintLibuvHandleInformation(env->event_loop(), stderr);
}
if (!queues_are_empty) {
return ExitCode::kStartupSnapshotFailure;
}
return ExitCode::kNoFailure;
}
ExitCode SnapshotBuilder::GenerateAsSource(
const char* out_path,
const std::vector<std::string>& args,
const std::vector<std::string>& exec_args,
const SnapshotConfig& config,
bool use_array_literals) {
std::string builder_script_content;
std::optional<std::string_view> builder_script_optional;
if (config.builder_script_path.has_value()) {
std::string_view builder_script_path = config.builder_script_path.value();
int r = ReadFileSync(&builder_script_content, builder_script_path.data());
if (r != 0) {
FPrintF(stderr,
"Cannot read main script %s for building snapshot. %s: %s",
builder_script_path,
uv_err_name(r),
uv_strerror(r));
return ExitCode::kGenericUserError;
}
builder_script_optional = builder_script_content;
}
std::ofstream out(out_path, std::ios::out | std::ios::binary);
if (!out) {
FPrintF(stderr, "Cannot open %s for output.\n", out_path);
return ExitCode::kGenericUserError;
}
SnapshotData data;
ExitCode exit_code =
Generate(&data, args, exec_args, builder_script_optional, config);
if (exit_code != ExitCode::kNoFailure) {
return exit_code;
}
FormatBlob(out, &data, use_array_literals);
if (!out) {
std::cerr << "Failed to write to " << out_path << "\n";
exit_code = node::ExitCode::kGenericUserError;
}
return exit_code;
}
SnapshotableObject::SnapshotableObject(Realm* realm,
Local<Object> wrap,
EmbedderObjectType type)
: BaseObject(realm, wrap), type_(type) {}
std::string SnapshotableObject::GetTypeName() const {
switch (type_) {
#define V(PropertyName, NativeTypeName) \
case EmbedderObjectType::k_##PropertyName: { \
return #NativeTypeName; \
}
SERIALIZABLE_OBJECT_TYPES(V)
#undef V
default: { UNREACHABLE(); }
}
}
void DeserializeNodeContextData(Local<Context> holder,
int index,
StartupData payload,
void* callback_data) {
// We will reset all the pointers in Environment::AssignToContext()
// via the realm constructor.
switch (index) {
case ContextEmbedderIndex::kEnvironment:
case ContextEmbedderIndex::kContextifyContext:
case ContextEmbedderIndex::kRealm:
case ContextEmbedderIndex::kContextTag: {
uint64_t index_64;
int size = sizeof(index_64);
CHECK_EQ(payload.raw_size, size);
memcpy(&index_64, payload.data, payload.raw_size);
CHECK_EQ(index_64, static_cast<uint64_t>(index));
break;
}
default:
UNREACHABLE();
}
}
StartupData SerializeNodeContextData(Local<Context> holder,
int index,
void* callback_data) {
// For pointer values, we need to return some non-empty data so that V8
// does not serialize them verbatim, making the snapshot unreproducible.
switch (index) {
case ContextEmbedderIndex::kEnvironment:
case ContextEmbedderIndex::kContextifyContext:
case ContextEmbedderIndex::kRealm:
case ContextEmbedderIndex::kContextTag: {
void* data = holder->GetAlignedPointerFromEmbedderData(
index, EmbedderDataTag::kPerContextData);
per_process::Debug(
DebugCategory::MKSNAPSHOT,
"Serialize context data, index=%d, holder=%p, ptr=%p\n",
static_cast<int>(index),
*holder,
data);
// We use uint64_t to avoid padding.
uint64_t index_64 = static_cast<uint64_t>(index);
// It must be allocated with new[] because V8 will call delete[] on it.
size_t size = sizeof(index_64);
char* startup_data = new char[size];
memcpy(startup_data, &index_64, size);
return {startup_data, static_cast<int>(size)};
}
default:
UNREACHABLE();
}
}
void DeserializeNodeInternalFields(Local<Object> holder,
int index,
StartupData payload,
void* callback_data) {
if (payload.raw_size == 0) {
return;
}
per_process::Debug(DebugCategory::MKSNAPSHOT,
"Deserialize internal field %d of %p, size=%d\n",
static_cast<int>(index),
(*holder),
static_cast<int>(payload.raw_size));
Environment* env = static_cast<Environment*>(callback_data);
// To deserialize the first field, check the type and re-tag the object.
if (index == BaseObject::kEmbedderType) {
int size = sizeof(EmbedderTypeInfo);
DCHECK_EQ(payload.raw_size, size);
EmbedderTypeInfo read_data;
memcpy(&read_data, payload.data, size);
// For now we only support non-cppgc objects.
CHECK_EQ(read_data.mode, EmbedderTypeInfo::MemoryMode::kBaseObject);
BaseObject::TagBaseObject(env->isolate_data(), holder);
return;
}
// To deserialize the second field, enqueue a deserialize request.
DCHECK_IS_SNAPSHOT_SLOT(index);
const InternalFieldInfoBase* info =
reinterpret_cast<const InternalFieldInfoBase*>(payload.data);
// TODO(joyeecheung): we can add a constant kNodeEmbedderId to the
// beginning of every InternalFieldInfoBase to ensure that we don't
// step on payloads that were not serialized by Node.js.
switch (info->type) {
#define V(PropertyName, NativeTypeName) \
case EmbedderObjectType::k_##PropertyName: { \
per_process::Debug(DebugCategory::MKSNAPSHOT, \
"Object %p is %s\n", \
(*holder), \
#NativeTypeName); \
env->EnqueueDeserializeRequest( \
NativeTypeName::Deserialize, \
holder, \
index, \
info->Copy<NativeTypeName::InternalFieldInfo>()); \
break; \
}
SERIALIZABLE_OBJECT_TYPES(V)
#undef V
default: {
// This should only be reachable during development when trying to
// deserialize a snapshot blob built by a version of Node.js that
// has more recognizable EmbedderObjectTypes than the deserializing
// Node.js binary.
fprintf(stderr,
"Unknown embedder object type %" PRIu8 ", possibly caused by "
"mismatched Node.js versions\n",
static_cast<uint8_t>(info->type));
ABORT();
}
}
}
StartupData SerializeNodeContextInternalFields(Local<Object> holder,
int index,
void* callback_data) {
// For the moment we do not set any internal fields in ArrayBuffer
// or ArrayBufferViews, so just return nullptr.
if (holder->IsArrayBuffer() || holder->IsArrayBufferView()) {
CHECK_NULL(holder->GetAlignedPointerFromInternalField(
index, EmbedderDataTag::kDefault));
return StartupData{nullptr, 0};
}
// Use the V8 convention and serialize unknown objects verbatim.
Environment* env = static_cast<Environment*>(callback_data);
if (!BaseObject::IsBaseObject(env->isolate_data(), holder)) {
per_process::Debug(DebugCategory::MKSNAPSHOT,
"Serialize unknown object, index=%d, holder=%p\n",
static_cast<int>(index),
*holder);
return StartupData{nullptr, 0};
}
per_process::Debug(DebugCategory::MKSNAPSHOT,
"Serialize BaseObject, index=%d, holder=%p\n",
static_cast<int>(index),
*holder);
BaseObject* object_ptr =
static_cast<BaseObject*>(holder->GetAlignedPointerFromInternalField(
BaseObject::kSlot, EmbedderDataTag::kDefault));
// If the native object is already set to null, ignore it.
if (object_ptr == nullptr) {
return StartupData{nullptr, 0};
}
DCHECK(object_ptr->is_snapshotable());
SnapshotableObject* obj = static_cast<SnapshotableObject*>(object_ptr);
// To serialize the type field, save data in a EmbedderTypeInfo.
if (index == BaseObject::kEmbedderType) {
int size = sizeof(EmbedderTypeInfo);
// We need to use placement new because V8 calls delete[] on the returned
// data.
// The () syntax at the end would zero-initialize the block and make
// the padding reproducible.
char* data = new char[size]();
// TODO(joyeecheung): support cppgc objects.
new (data) EmbedderTypeInfo(obj->type(),
EmbedderTypeInfo::MemoryMode::kBaseObject);
return StartupData{data, size};
}
// To serialize the slot field, invoke Serialize() method on the object.
DCHECK_IS_SNAPSHOT_SLOT(index);
per_process::Debug(DebugCategory::MKSNAPSHOT,
"Object %p is %s, ",
*holder,
obj->GetTypeName());
InternalFieldInfoBase* info = obj->Serialize(index);
per_process::Debug(DebugCategory::MKSNAPSHOT,
"payload size=%d\n",
static_cast<int>(info->length));
return StartupData{reinterpret_cast<const char*>(info),
static_cast<int>(info->length)};
}
void SerializeSnapshotableObjects(Realm* realm,
SnapshotCreator* creator,
RealmSerializeInfo* info) {
HandleScope scope(realm->isolate());
Local<Context> context = realm->context();
uint32_t i = 0;
realm->ForEachBaseObject([&](BaseObject* obj) {
// If there are any BaseObjects that are not snapshotable left
// during context serialization, V8 would crash due to unregistered
// global handles and print detailed information about them.
if (!obj->is_snapshotable()) {
return;
}
SnapshotableObject* ptr = static_cast<SnapshotableObject*>(obj);
std::string type_name = ptr->GetTypeName();
per_process::Debug(DebugCategory::MKSNAPSHOT,
"Serialize snapshotable object %i (%p), "
"object=%p, type=%s\n",
static_cast<int>(i),
ptr,
*(ptr->object()),
type_name);
if (ptr->PrepareForSerialization(context, creator)) {
SnapshotIndex index = creator->AddData(context, obj->object());
per_process::Debug(DebugCategory::MKSNAPSHOT,
"Serialized with index=%d\n",
static_cast<int>(index));
info->native_objects.push_back({type_name, i, index});
}
i++;
});
}
void RunEmbedderPreload(const FunctionCallbackInfo<Value>& args) {
Environment* env = Environment::GetCurrent(args);
CHECK(env->embedder_preload());
CHECK_EQ(args.Length(), 2);
Local<Value> process_obj = args[0];
Local<Value> require_fn = args[1];
CHECK(process_obj->IsObject());
CHECK(require_fn->IsFunction());
env->embedder_preload()(env, process_obj, require_fn);
}
void CompileSerializeMain(const FunctionCallbackInfo<Value>& args) {
CHECK(args[0]->IsString());
Local<String> filename = args[0].As<String>();
Local<String> source = args[1].As<String>();
Isolate* isolate = args.GetIsolate();
Local<Context> context = isolate->GetCurrentContext();
// TODO(joyeecheung): do we need all of these? Maybe we would want a less
// internal version of them.
LocalVector<String> parameters(
isolate,
{
FIXED_ONE_BYTE_STRING(isolate, "require"),
FIXED_ONE_BYTE_STRING(isolate, "__filename"),
FIXED_ONE_BYTE_STRING(isolate, "__dirname"),
});
ScriptOrigin script_origin(filename, 0, 0, true);
ScriptCompiler::Source script_source(source, script_origin);
MaybeLocal<Function> maybe_fn =
ScriptCompiler::CompileFunction(context,
&script_source,
parameters.size(),
parameters.data(),
0,
nullptr);
Local<Function> fn;
if (maybe_fn.ToLocal(&fn)) {
args.GetReturnValue().Set(fn);
}
}
void SetSerializeCallback(const FunctionCallbackInfo<Value>& args) {
Environment* env = Environment::GetCurrent(args);
CHECK(env->snapshot_serialize_callback().IsEmpty());
CHECK(args[0]->IsFunction());
env->set_snapshot_serialize_callback(args[0].As<Function>());
}
void SetDeserializeCallback(const FunctionCallbackInfo<Value>& args) {
Environment* env = Environment::GetCurrent(args);
CHECK(env->snapshot_deserialize_callback().IsEmpty());
CHECK(args[0]->IsFunction());
env->set_snapshot_deserialize_callback(args[0].As<Function>());
}
void SetDeserializeMainFunction(const FunctionCallbackInfo<Value>& args) {
Environment* env = Environment::GetCurrent(args);
CHECK(env->snapshot_deserialize_main().IsEmpty());
CHECK(args[0]->IsFunction());
env->set_snapshot_deserialize_main(args[0].As<Function>());
}
constexpr const char* kAnonymousMainPath = "__node_anonymous_main";
std::string GetAnonymousMainPath() {
return kAnonymousMainPath;
}
namespace mksnapshot {
BindingData::BindingData(Realm* realm,
v8::Local<v8::Object> object,
InternalFieldInfo* info)
: SnapshotableObject(realm, object, type_int),
is_building_snapshot_buffer_(
realm->isolate(),
1,
MAYBE_FIELD_PTR(info, is_building_snapshot_buffer)) {
if (info == nullptr) {
object
->Set(
realm->context(),
FIXED_ONE_BYTE_STRING(realm->isolate(), "isBuildingSnapshotBuffer"),
is_building_snapshot_buffer_.GetJSArray())
.Check();
} else {
is_building_snapshot_buffer_.Deserialize(realm->context());
}
// Reset the status according to the current state of the realm.
bool is_building_snapshot = realm->isolate_data()->is_building_snapshot();
DCHECK_IMPLIES(is_building_snapshot,
realm->isolate_data()->snapshot_data() == nullptr);
is_building_snapshot_buffer_[0] = is_building_snapshot ? 1 : 0;
is_building_snapshot_buffer_.MakeWeak();
}
bool BindingData::PrepareForSerialization(Local<Context> context,
v8::SnapshotCreator* creator) {
DCHECK_NULL(internal_field_info_);
internal_field_info_ = InternalFieldInfoBase::New<InternalFieldInfo>(type());
internal_field_info_->is_building_snapshot_buffer =
is_building_snapshot_buffer_.Serialize(context, creator);
// Return true because we need to maintain the reference to the binding from
// JS land.
return true;
}
InternalFieldInfoBase* BindingData::Serialize(int index) {
DCHECK_IS_SNAPSHOT_SLOT(index);
InternalFieldInfo* info = internal_field_info_;
internal_field_info_ = nullptr;
return info;
}
void BindingData::Deserialize(Local<Context> context,
Local<Object> holder,
int index,
InternalFieldInfoBase* info) {
DCHECK_IS_SNAPSHOT_SLOT(index);
v8::HandleScope scope(Isolate::GetCurrent());
Realm* realm = Realm::GetCurrent(context);
// Recreate the buffer in the constructor.
InternalFieldInfo* casted_info = static_cast<InternalFieldInfo*>(info);
BindingData* binding =
realm->AddBindingData<BindingData>(holder, casted_info);
CHECK_NOT_NULL(binding);
}
void BindingData::MemoryInfo(MemoryTracker* tracker) const {
tracker->TrackField("is_building_snapshot_buffer",
is_building_snapshot_buffer_);
}
void CreatePerContextProperties(Local<Object> target,
Local<Value> unused,
Local<Context> context,
void* priv) {
Realm* realm = Realm::GetCurrent(context);
realm->AddBindingData<BindingData>(target);
}
void CreatePerIsolateProperties(IsolateData* isolate_data,
Local<ObjectTemplate> target) {
Isolate* isolate = isolate_data->isolate();
SetMethod(isolate, target, "runEmbedderPreload", RunEmbedderPreload);
SetMethod(isolate, target, "compileSerializeMain", CompileSerializeMain);
SetMethod(isolate, target, "setSerializeCallback", SetSerializeCallback);
SetMethod(isolate, target, "setDeserializeCallback", SetDeserializeCallback);
SetMethod(isolate,
target,
"setDeserializeMainFunction",
SetDeserializeMainFunction);
target->Set(FIXED_ONE_BYTE_STRING(isolate, "anonymousMainPath"),
OneByteString(isolate, kAnonymousMainPath));
}
void RegisterExternalReferences(ExternalReferenceRegistry* registry) {
registry->Register(RunEmbedderPreload);
registry->Register(CompileSerializeMain);
registry->Register(SetSerializeCallback);
registry->Register(SetDeserializeCallback);
registry->Register(SetDeserializeMainFunction);
}
} // namespace mksnapshot
} // namespace node
NODE_BINDING_CONTEXT_AWARE_INTERNAL(
mksnapshot, node::mksnapshot::CreatePerContextProperties)
NODE_BINDING_PER_ISOLATE_INIT(mksnapshot,
node::mksnapshot::CreatePerIsolateProperties)
NODE_BINDING_EXTERNAL_REFERENCE(mksnapshot,
node::mksnapshot::RegisterExternalReferences)
Reference in New Issue View Git Blame Copy Permalink