electron/shell/browser/javascript_environment.cc

115 lines
3.7 KiB
C++

// Copyright (c) 2013 GitHub, Inc.
// Use of this source code is governed by the MIT license that can be
// found in the LICENSE file.
#include "shell/browser/javascript_environment.h"
#include <memory>
#include <string>
#include "base/command_line.h"
#include "base/task/current_thread.h"
#include "base/task/thread_pool/initialization_util.h"
#include "base/threading/thread_task_runner_handle.h"
#include "content/public/common/content_switches.h"
#include "gin/array_buffer.h"
#include "gin/v8_initializer.h"
#include "shell/browser/microtasks_runner.h"
#include "shell/common/gin_helper/cleaned_up_at_exit.h"
#include "shell/common/node_includes.h"
#include "tracing/trace_event.h"
namespace {
v8::Isolate* g_isolate;
}
namespace electron {
JavascriptEnvironment::JavascriptEnvironment(uv_loop_t* event_loop)
: isolate_(Initialize(event_loop)),
isolate_holder_(base::ThreadTaskRunnerHandle::Get(),
gin::IsolateHolder::kSingleThread,
gin::IsolateHolder::kAllowAtomicsWait,
gin::IsolateHolder::IsolateType::kUtility,
gin::IsolateHolder::IsolateCreationMode::kNormal,
isolate_),
locker_(isolate_) {
isolate_->Enter();
v8::HandleScope scope(isolate_);
auto context = node::NewContext(isolate_);
context_ = v8::Global<v8::Context>(isolate_, context);
context->Enter();
}
JavascriptEnvironment::~JavascriptEnvironment() {
{
v8::Locker locker(isolate_);
v8::HandleScope scope(isolate_);
context_.Get(isolate_)->Exit();
}
isolate_->Exit();
g_isolate = nullptr;
}
v8::Isolate* JavascriptEnvironment::Initialize(uv_loop_t* event_loop) {
auto* cmd = base::CommandLine::ForCurrentProcess();
// --js-flags.
std::string js_flags = cmd->GetSwitchValueASCII(switches::kJavaScriptFlags);
if (!js_flags.empty())
v8::V8::SetFlagsFromString(js_flags.c_str(), js_flags.size());
// The V8Platform of gin relies on Chromium's task schedule, which has not
// been started at this point, so we have to rely on Node's V8Platform.
auto* tracing_agent = node::CreateAgent();
auto* tracing_controller = tracing_agent->GetTracingController();
node::tracing::TraceEventHelper::SetAgent(tracing_agent);
platform_ = node::CreatePlatform(
base::RecommendedMaxNumberOfThreadsInThreadGroup(3, 8, 0.1, 0),
tracing_controller);
v8::V8::InitializePlatform(platform_);
gin::IsolateHolder::Initialize(gin::IsolateHolder::kNonStrictMode,
gin::ArrayBufferAllocator::SharedInstance(),
nullptr /* external_reference_table */,
false /* create_v8_platform */);
v8::Isolate* isolate = v8::Isolate::Allocate();
platform_->RegisterIsolate(isolate, event_loop);
g_isolate = isolate;
return isolate;
}
// static
v8::Isolate* JavascriptEnvironment::GetIsolate() {
CHECK(g_isolate);
return g_isolate;
}
void JavascriptEnvironment::OnMessageLoopCreated() {
DCHECK(!microtasks_runner_);
microtasks_runner_ = std::make_unique<MicrotasksRunner>(isolate());
base::CurrentThread::Get()->AddTaskObserver(microtasks_runner_.get());
}
void JavascriptEnvironment::OnMessageLoopDestroying() {
DCHECK(microtasks_runner_);
{
v8::Locker locker(isolate_);
v8::HandleScope scope(isolate_);
gin_helper::CleanedUpAtExit::DoCleanup();
}
base::CurrentThread::Get()->RemoveTaskObserver(microtasks_runner_.get());
platform_->DrainTasks(isolate_);
platform_->UnregisterIsolate(isolate_);
}
NodeEnvironment::NodeEnvironment(node::Environment* env) : env_(env) {}
NodeEnvironment::~NodeEnvironment() {
node::FreeEnvironment(env_);
}
} // namespace electron