webkit js

dom相關：

https://w3c.github.io/uievents/

https://dom.spec.whatwg.org/

工作原理：

https://www.html5rocks.com/en/tutorials/internals/howbrowserswork/

自己添加更多dom函數用js而不是通過c++：https://www.chromium.org/blink/blink-in-js

void Document::SetShowBeforeUnloadDialog(bool show_dialog) {
if (!mime_handler_view_before_unload_event_listener_) {
if (!show_dialog)
return;

mime_handler_view_before_unload_event_listener_ =
MakeGarbageCollected<BeforeUnloadEventListener>(this);
domWindow()->addEventListener(
event_type_names::kBeforeunload,
mime_handler_view_before_unload_event_listener_, false);
}      

TEST_F(WebViewTest, SubframeBeforeUnloadUseCounter) {
  RegisterMockedHttpURLLoad("visible_iframe.html");
  RegisterMockedHttpURLLoad("single_iframe.html");
  WebViewImpl* web_view =
      web_view_helper_.InitializeAndLoad(base_url_ + "single_iframe.html");

  WebLocalFrame* frame = web_view_helper_.LocalMainFrame();
  Document* document =
      To<LocalFrame>(web_view_helper_.GetWebView()->GetPage()->MainFrame())
          ->GetDocument();

  // Add a beforeunload handler in the main frame. Make sure firing
  // beforeunload doesn't increment the subframe use counter.
  {
    frame->ExecuteScript(
        WebScriptSource("addEventListener('beforeunload', function() {});"));
    web_view->MainFrameImpl()->DispatchBeforeUnloadEvent(false);
    EXPECT_FALSE(
        document->IsUseCounted(WebFeature::kSubFrameBeforeUnloadFired));
  }

  // Add a beforeunload handler in the iframe and dispatch. Make sure we do
  // increment the use counter for subframe beforeunloads.
  {
    frame->ExecuteScript(WebScriptSource(
        "document.getElementsByTagName('iframe')[0].contentWindow."
        "addEventListener('beforeunload', function() {});"));
    To<WebLocalFrameImpl>(
        web_view->MainFrame()->FirstChild()->ToWebLocalFrame())
        ->DispatchBeforeUnloadEvent(false);

    Document* child_document = To<LocalFrame>(web_view_helper_.GetWebView()
                                                  ->GetPage()
                                                  ->MainFrame()
                                                  ->Tree()
                                                  .FirstChild())
                                   ->GetDocument();
    EXPECT_TRUE(
        child_document->IsUseCounted(WebFeature::kSubFrameBeforeUnloadFired));
  }
}      

third_party/blink/renderer/bindings/templates/

// This file has been auto-generated from the Jinja2 template

// third_party/blink/renderer/bindings/templates/interface.cc.tmpl

// by the script code_generator_v8.py.

// third_party/blink/renderer/bindings/templates/interface.h.tmpl

js AddEventListenerMethodCallback的方法實作在

\src\out\Testing\gen\third_party\blink\renderer\bindings\modules\v8\v8_context_snapshot_external_references.cc

    reinterpret_cast<intptr_t>(V8Window::AlertMethodCallback),

D:\dev\electron7\src\out\Testing\gen\third_party\blink\renderer\bindings\core\v8\v8_window.cc

static constexpr V8DOMConfiguration::MethodConfiguration kV8WindowMethods[] = {

{"stop", V8Window::StopMethodCallback, 0, v8::None, V8DOMConfiguration::kOnInstance, V8DOMConfiguration::kCheckHolder, V8DOMConfiguration::kCheckAccess, V8DOMConfiguration::kHasSideEffect, V8DOMConfiguration::kAllWorlds},

{"open", V8Window::OpenMethodCallback, 0, v8::None, V8DOMConfiguration::kOnInstance, V8DOMConfiguration::kCheckHolder, V8DOMConfiguration::kCheckAccess, V8DOMConfiguration::kHasSideEffect, V8DOMConfiguration::kAllWorlds},

{"alert", V8Window::AlertMethodCallback, 0, v8::None, V8DOMConfiguration::kOnInstance, V8DOMConfiguration::kCheckHolder, V8DOMConfiguration::kCheckAccess, V8DOMConfiguration::kHasSideEffect, V8DOMConfiguration::kAllWorlds},

{"confirm", V8Window::ConfirmMethodCallback, 0, v8::None, V8DOMConfiguration::kOnInstance, V8DOMConfiguration::kCheckHolder, V8DOMConfiguration::kCheckAccess, V8DOMConfiguration::kHasSideEffect, V8DOMConfiguration::kAllWorlds},

{"prompt", V8Window::PromptMethodCallback, 0, v8::None, V8DOMConfiguration::kOnInstance, V8DOMConfiguration::kCheckHolder, V8DOMConfiguration::kCheckAccess, V8DOMConfiguration::kHasSideEffect, V8DOMConfiguration::kAllWorlds},

JS調用到alert的堆棧：

blink_core.dll!blink::LocalDOMWindow::alert(blink::ScriptState * script_state, const WTF::String & message) 行 664 C++

blink_core.dll!blink::dom_window_v8_internal::Alert2Method(const v8::FunctionCallbackInfo<v8::Value> & info) 行 5382 C++

blink_core.dll!blink::dom_window_v8_internal::AlertMethod(const v8::FunctionCallbackInfo<v8::Value> & info) 行 5404 C++

blink_core.dll!blink::V8Window::AlertMethodCallback(const v8::FunctionCallbackInfo<v8::Value> & info) 行 12441 C++

v8.dll!v8::internal::FunctionCallbackArguments::Call(v8::internal::CallHandlerInfo handler) 行 159 C++

v8.dll!v8::internal::`anonymous namespace'::HandleApiCallHelper<0>(v8::internal::Isolate * isolate, v8::internal::Handle<v8::internal::HeapObject> function, v8::internal::Handle<v8::internal::HeapObject> new_target, v8::internal::Handle<v8::internal::FunctionTemplateInfo> fun_data, v8::internal::Handle<v8::internal::Object> receiver, v8::internal::BuiltinArguments args) 行 113 C++

v8.dll!v8::internal::Builtin_Impl_HandleApiCall(v8::internal::BuiltinArguments args, v8::internal::Isolate * isolate) 行 141 C++

v8.dll!v8::internal::Builtin_HandleApiCall(int args_length, unsigned __int64 * args_object, v8::internal::Isolate * isolate) 行 129 C++

[外部代碼]

[内聯架構] v8.dll!v8::internal::GeneratedCode<unsigned long long,unsigned long long,unsigned long long,unsigned long long,unsigned long long,long long,unsigned long long **>::Call(unsigned __int64 args, unsigned __int64 args, unsigned __int64 args, unsigned __int64 args, __int64 args, unsigned __int64 * * args) 行 138 C++

v8.dll!v8::internal::`anonymous namespace'::Invoke(v8::internal::Isolate * isolate, const v8::internal::`anonymous namespace'::InvokeParams & params) 行 266 C++

v8.dll!v8::internal::Execution::Call(v8::internal::Isolate * isolate, v8::internal::Handle<v8::internal::Object> callable, v8::internal::Handle<v8::internal::Object> receiver, int argc, v8::internal::Handle<v8::internal::Object> * argv) 行 358 C++

v8.dll!v8::Script::Run(v8::Local<v8::Context> context) 行 2159 C++

blink_core.dll!blink::V8ScriptRunner::RunCompiledScript(v8::Isolate * isolate, v8::Local<v8::Script> script, blink::ExecutionContext * context) 行 340 C++

blink_core.dll!blink::ScriptController::ExecuteScriptAndReturnValue(v8::Local<v8::Context> context, const blink::ScriptSourceCode & source, const blink::KURL & base_url, blink::SanitizeScriptErrors sanitize_script_errors, const blink::ScriptFetchOptions & fetch_options) 行 133 C++

blink_core.dll!blink::ScriptController::EvaluateScriptInMainWorld(const blink::ScriptSourceCode & source_code, const blink::KURL & base_url, blink::SanitizeScriptErrors sanitize_script_errors, const blink::ScriptFetchOptions & fetch_options, blink::ScriptController::ExecuteScriptPolicy policy) 行 353 C++

> blink_core.dll!blink::ScriptController::ExecuteScriptInMainWorld(const blink::ScriptSourceCode & source_code, const blink::KURL & base_url, blink::SanitizeScriptErrors sanitize_script_errors, const blink::ScriptFetchOptions & fetch_options) 行 321 C++

blink_core.dll!blink::ClassicScript::RunScript(blink::LocalFrame * frame, const blink::SecurityOrigin * security_origin) 行 26 C++

blink_core.dll!blink::PendingScript::ExecuteScriptBlockInternal(blink::Script * script, blink::ScriptElementBase * element, bool was_canceled, bool is_external, bool created_during_document_write, base::TimeTicks parser_blocking_load_start_time, bool is_controlled_by_script_runner) 行 265 C++

blink_core.dll!blink::PendingScript::ExecuteScriptBlock(const blink::KURL & document_url) 行 171 C++

blink_core.dll!blink::ScriptLoader::PrepareScript(const WTF::TextPosition & script_start_position, blink::ScriptLoader::LegacyTypeSupport support_legacy_types) 行 890 C++

blink_core.dll!blink::HTMLParserScriptRunner::ProcessScriptElementInternal(blink::Element * script, const WTF::TextPosition & script_start_position) 行 599 C++

blink_core.dll!blink::HTMLParserScriptRunner::ProcessScriptElement(blink::Element * script_element, const WTF::TextPosition & script_start_position) 行 333 C++

blink_core.dll!blink::HTMLDocumentParser::RunScriptsForPausedTreeBuilder() 行 299 C++

blink_core.dll!blink::HTMLDocumentParser::ProcessTokenizedChunkFromBackgroundParser(std::unique_ptr<blink::HTMLDocumentParser::TokenizedChunk,std::default_delete<blink::HTMLDocumentParser::TokenizedChunk>> pop_chunk) 行 539 C++

blink_core.dll!blink::HTMLDocumentParser::PumpPendingSpeculations() 行 595 C++

blink_core.dll!blink::HTMLDocumentParser::ResumeParsingAfterYield() 行 288 C++

blink_core.dll!blink::HTMLParserScheduler::ContinueParsing() 行 141 C++

void V8Window::AlertMethodCallback(const v8::FunctionCallbackInfo<v8::Value>& info) {

RUNTIME_CALL_TIMER_SCOPE_DISABLED_BY_DEFAULT(info.GetIsolate(), "Blink_DOMWindow_alert");

dom_window_v8_internal::AlertMethod(info);

}

void V8Window::ConfirmMethodCallback(const v8::FunctionCallbackInfo<v8::Value>& info) {

RUNTIME_CALL_TIMER_SCOPE_DISABLED_BY_DEFAULT(info.GetIsolate(), "Blink_DOMWindow_confirm");

ExecutionContext* execution_context_for_measurement = CurrentExecutionContext(info.GetIsolate());

UseCounter::Count(execution_context_for_measurement, WebFeature::kV8Window_Confirm_Method);

dom_window_v8_internal::ConfirmMethod(info);

void V8Window::PromptMethodCallback(const v8::FunctionCallbackInfo<v8::Value>& info) {

RUNTIME_CALL_TIMER_SCOPE_DISABLED_BY_DEFAULT(info.GetIsolate(), "Blink_DOMWindow_prompt");

UseCounter::Count(execution_context_for_measurement, WebFeature::kV8Window_Prompt_Method);

dom_window_v8_internal::PromptMethod(info);

javascript的window::setInterval的内部實作

調用序列圖如下:

javascript的setInterval

-->jsDOMWindowPrototypeFunctionSetInterval

-->JSDOMWindow::setInterval

-->DOMWindow::setInterval

-->DOMTimer::install(context, action, timeout, false);

#########################################################################################

附

WebCore的timer實作

最基本有幾個類，

--TimerBase

--ThreadTimers

包含TimerBase的heap堆和SharedTimer的指針

--SharedTimer

--TimerBase有一些子類，如-->SuspendableTimer-->DOMTimer, Timer等

setNextFireTime() timer開始的時候，都要調用這個函數，這裡把具體的timer更新或者插入到ThreadTimers的堆中

fired() 純虛函數

--ThreadTimers

updateSharedTimer() start timer

sharedTimerFired() fired函數，設定為内部的SharedTimer的callback函數

--SharedTimer

實作依賴具體的平台，如mac, gtk, qt等

有兩個具體的實作MainThreadSharedTimer和WorkerSharedTimer