Hook main queue processing to update requests.

Telegram/SourceFiles/core/main_queue_processor.cpp

@@ -8,73 +8,101 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 #include "core/main_queue_processor.h"
 
 #include "core/sandbox.h"
+#include "platform/platform_specific.h"
 
 namespace Core {
 namespace {
 
-QMutex ProcessorMutex;
-MainQueueProcessor *ProcessorInstance/* = nullptr*/;
-
 constexpr auto kProcessorEvent = QEvent::Type(QEvent::User + 1);
 static_assert(kProcessorEvent < QEvent::MaxUser);
 
-class ProcessorEvent : public QEvent {
-public:
-	ProcessorEvent(void (*callable)(void*), void *argument);
-
-	void process();
-
-private:
-	void (*_callable)(void*) = nullptr;
-	void *_argument = nullptr;
+QMutex ProcessorMutex;
+MainQueueProcessor *ProcessorInstance/* = nullptr*/;
 
+enum class ProcessState : int {
+	Processed,
+	FillingUp,
+	Waiting,
 };
 
-ProcessorEvent::ProcessorEvent(void (*callable)(void*), void *argument)
-: QEvent(kProcessorEvent)
-, _callable(callable)
-, _argument(argument) {
+std::atomic<ProcessState> MainQueueProcessState/* = ProcessState(0)*/;
+void (*MainQueueProcessCallback)(void*)/* = nullptr*/;
+void *MainQueueProcessArgument/* = nullptr*/;
+
+void PushToMainQueueGeneric(void (*callable)(void*), void *argument) {
+	Expects(Platform::UseMainQueueGeneric());
+
+	auto expected = ProcessState::Processed;
+	const auto fill = MainQueueProcessState.compare_exchange_strong(
+		expected,
+		ProcessState::FillingUp);
+	if (fill) {
+		MainQueueProcessCallback = callable;
+		MainQueueProcessArgument = argument;
+		MainQueueProcessState.store(ProcessState::Waiting);
+	}
+
+	auto event = std::make_unique<QEvent>(kProcessorEvent);
+
+	QMutexLocker lock(&ProcessorMutex);
+	if (ProcessorInstance) {
+		QApplication::postEvent(ProcessorInstance, event.release());
+	}
 }
 
-void ProcessorEvent::process() {
-	_callable(_argument);
-}
+void DrainMainQueueGeneric() {
+	Expects(Platform::UseMainQueueGeneric());
 
-void ProcessObservables() {
-	Global::RefHandleObservables().call();
+	if (MainQueueProcessState.load() != ProcessState::Waiting) {
+		return;
+	}
+	const auto callback = MainQueueProcessCallback;
+	const auto argument = MainQueueProcessArgument;
+	MainQueueProcessState.store(ProcessState::Processed);
+
+	callback(argument);
 }
 
 } // namespace
 
 MainQueueProcessor::MainQueueProcessor() {
-	acquire();
-
-	crl::init_main_queue([](void (*callable)(void*), void *argument) {
-		QMutexLocker lock(&ProcessorMutex);
-
-		if (ProcessorInstance) {
-			const auto event = new ProcessorEvent(callable, argument);
-			QApplication::postEvent(ProcessorInstance, event);
-		}
-	});
-	crl::wrap_main_queue([](void (*callable)(void*), void *argument) {
-		Sandbox::Instance().customEnterFromEventLoop([&] {
-			callable(argument);
+	if constexpr (Platform::UseMainQueueGeneric()) {
+		acquire();
+		crl::init_main_queue(PushToMainQueueGeneric);
+	} else {
+		crl::wrap_main_queue([](void (*callable)(void*), void *argument) {
+			Sandbox::Instance().customEnterFromEventLoop([&] {
+				callable(argument);
+			});
 		});
-	});
+	}
 
-	base::InitObservables(ProcessObservables);
+	Core::Sandbox::Instance().widgetUpdateRequests(
+	) | rpl::start_with_next([] {
+		if constexpr (Platform::UseMainQueueGeneric()) {
+			DrainMainQueueGeneric();
+		} else {
+			Platform::DrainMainQueue();
+		}
+	}, _lifetime);
+
+	base::InitObservables([] {
+		Global::RefHandleObservables().call();
+	});
 }
 
 bool MainQueueProcessor::event(QEvent *event) {
-	if (event->type() == kProcessorEvent) {
-		static_cast<ProcessorEvent*>(event)->process();
-		return true;
+	if constexpr (Platform::UseMainQueueGeneric()) {
+		if (event->type() == kProcessorEvent) {
+			DrainMainQueueGeneric();
+			return true;
+		}
 	}
 	return QObject::event(event);
 }
 
 void MainQueueProcessor::acquire() {
+	Expects(Platform::UseMainQueueGeneric());
 	Expects(ProcessorInstance == nullptr);
 
 	QMutexLocker lock(&ProcessorMutex);
@@ -82,6 +110,7 @@ void MainQueueProcessor::acquire() {
 }
 
 void MainQueueProcessor::release() {
+	Expects(Platform::UseMainQueueGeneric());
 	Expects(ProcessorInstance == this);
 
 	QMutexLocker lock(&ProcessorMutex);
@@ -89,7 +118,9 @@ void MainQueueProcessor::release() {
 }
 
 MainQueueProcessor::~MainQueueProcessor() {
-	release();
+	if constexpr (Platform::UseMainQueueGeneric()) {
+		release();
+	}
 }
 
 } // namespace

Telegram/SourceFiles/core/main_queue_processor.h

@@ -21,6 +21,8 @@ private:
 	void acquire();
 	void release();
 
+	rpl::lifetime _lifetime;
+
 };
 
 } // namespace Core

Telegram/SourceFiles/core/sandbox.cpp

@@ -503,14 +503,6 @@ bool Sandbox::notify(QObject *receiver, QEvent *e) {
 	const auto type = e->type();
 	if (type == QEvent::UpdateRequest) {
 		_widgetUpdateRequests.fire({});
-		// Profiling.
-		//const auto time = crl::now();
-		//LOG(("[%1] UPDATE STARTED").arg(time));
-		//const auto guard = gsl::finally([&] {
-		//	const auto now = crl::now();
-		//	LOG(("[%1] UPDATE FINISHED (%2)").arg(now).arg(now - time));
-		//});
-		//return QApplication::notify(receiver, e);
 	}
 	return QApplication::notify(receiver, e);
 }

Telegram/SourceFiles/platform/linux/specific_linux.h

@@ -7,6 +7,8 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 */
 #pragma once
 
+#include "platform/platform_specific.h"
+
 #include <execinfo.h>
 #include <signal.h>
 
@@ -39,6 +41,10 @@ inline std::optional<crl::time> LastUserInputTime() {
 	return std::nullopt;
 }
 
+inline constexpr bool UseMainQueueGeneric() {
+	return true;
+}
+
 } // namespace Platform
 
 inline QString psServerPrefix() {

Telegram/SourceFiles/platform/mac/specific_mac.h

@@ -7,6 +7,7 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 */
 #pragma once
 
+#include "platform/platform_specific.h"
 #include "platform/mac/specific_mac_p.h"
 
 namespace Data {
@@ -23,6 +24,10 @@ QString CurrentExecutablePath(int argc, char *argv[]);
 
 void RemoveQuarantine(const QString &path);
 
+inline constexpr bool UseMainQueueGeneric() {
+	return false;
+}
+
 namespace ThirdParty {
 
 inline void start() {

Telegram/SourceFiles/platform/mac/specific_mac.mm

@@ -29,6 +29,10 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 #include <mach-o/dyld.h>
 #include <AVFoundation/AVFoundation.h>
 
+extern "C" {
+void _dispatch_main_queue_callback_4CF(mach_msg_header_t *msg);
+} // extern "C"
+
 namespace {
 
 QStringList _initLogs;
@@ -139,6 +143,10 @@ void RemoveQuarantine(const QString &path) {
 	removexattr(local.data(), kQuarantineAttribute, 0);
 }
 
+void DrainMainQueue() {
+	_dispatch_main_queue_callback_4CF(nullptr);
+}
+
 void RegisterCustomScheme() {
 #ifndef TDESKTOP_DISABLE_REGISTER_CUSTOM_SCHEME
 	OSStatus result = LSSetDefaultHandlerForURLScheme(CFSTR("tg"), (CFStringRef)[[NSBundle mainBundle] bundleIdentifier]);

Telegram/SourceFiles/platform/platform_specific.h

@@ -45,6 +45,9 @@ bool OpenSystemSettings(SystemSettingsType type);
 	return LastUserInputTime().has_value();
 }
 
+[[nodiscard]] constexpr bool UseMainQueueGeneric();
+void DrainMainQueue(); // Needed only if UseMainQueueGeneric() is false.
+
 namespace ThirdParty {
 
 void start();

Telegram/SourceFiles/platform/win/specific_win.h

@@ -7,6 +7,7 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 */
 #pragma once
 
+#include "platform/platform_specific.h"
 #include "platform/win/wrapper_windows_h.h"
 
 namespace Data {
@@ -38,6 +39,10 @@ inline void ReInitOnTopPanel(QWidget *panel) {
 
 QString CurrentExecutablePath(int argc, char *argv[]);
 
+inline constexpr bool UseMainQueueGeneric() {
+	return true;
+}
+
 namespace ThirdParty {
 
 void start();