proxygen: folly::HHWheelTimer::Callback Class Reference

#include <HHWheelTimer.h>

Inheritance diagram for folly::HHWheelTimer::Callback:

Public Member Functions
	Callback ()=default

virtual	~Callback ()

virtual void	timeoutExpired () noexcept=0

virtual void	callbackCanceled () noexcept

void	cancelTimeout ()

bool	isScheduled () const

std::chrono::milliseconds	getTimeRemaining ()

Protected Member Functions
virtual std::chrono::steady_clock::time_point	getCurTime ()

Private Types
typedef boost::intrusive::list< Callback, boost::intrusive::constant_time_size< false > >	List

Private Member Functions
std::chrono::milliseconds	getTimeRemaining (std::chrono::steady_clock::time_point now) const

void	setScheduled (HHWheelTimer *wheel, std::chrono::milliseconds)

void	cancelTimeoutImpl ()

Private Attributes
HHWheelTimer *	wheel_ {nullptr}

std::chrono::steady_clock::time_point	expiration_ {}

int	bucket_ {-1}

std::shared_ptr< RequestContext >	requestContext_

Friends
class	HHWheelTimer

Detailed Description

A callback to be notified when a timeout has expired.

Definition at line 68 of file HHWheelTimer.h.

Member Typedef Documentation

typedef boost::intrusive:: list<Callback, boost::intrusive::constant_time_size<false> > folly::HHWheelTimer::Callback::List

private

Definition at line 145 of file HHWheelTimer.h.

Constructor & Destructor Documentation

folly::HHWheelTimer::Callback::Callback ( )

default

Callback::~Callback ( )

virtual

Definition at line 46 of file HHWheelTimer.cpp.

References cancelTimeout(), and isScheduled().

                                 {
   if (isScheduled()) {
     cancelTimeout();
   }
 }

Member Function Documentation

virtual void folly::HHWheelTimer::Callback::callbackCanceled ( )

inlinevirtualnoexcept

This callback was canceled. The default implementation is to just proxy to timeoutExpired but if you care about the difference between the timeout finishing or being canceled you can override this.

Reimplemented in proxygen::HTTPTransaction::RateLimitCallback.

Definition at line 83 of file HHWheelTimer.h.

References timeoutExpired().

                                              {
       timeoutExpired();
     }

void folly::HHWheelTimer::Callback::cancelTimeout ( )

inline

Cancel the timeout, if it is running.

If the timeout is not scheduled, cancelTimeout() does nothing.

Definition at line 92 of file HHWheelTimer.h.

References cancelTimeoutImpl(), and wheel_.

Referenced by proxygen::HTTP2PriorityQueue::Node::addChild(), proxygen::HTTP2PriorityQueue::Node::convertVirtualNode(), wangle::ConnectionManager::dropAllConnections(), proxygen::HTTPTransaction::markIngressComplete(), proxygen::HTTPSession::onConnectionSendWindowOpen(), proxygen::HTTPSession::onWriteSuccess(), proxygen::HTTPTransaction::pauseIngress(), proxygen::HTTPSession::pauseReadsImpl(), wangle::ConnectionManager::removeConnection(), folly::HHWheelTimer::scheduleTimeout(), proxygen::HTTPSession::shutdownTransportWithReset(), proxygen::HTTPTransaction::updateReadTimeout(), ~Callback(), proxygen::HTTPSession::~HTTPSession(), and proxygen::HTTPTransaction::~HTTPTransaction().

                          {
       if (wheel_ == nullptr) {
         // We're not scheduled, so there's nothing to do.
         return;
       }
       cancelTimeoutImpl();
     }

void Callback::cancelTimeoutImpl ( )

private

Definition at line 63 of file HHWheelTimer.cpp.

References folly::HHWheelTimer::bitmap_, bucket_, folly::HHWheelTimer::buckets_, folly::HHWheelTimer::count_, expiration_, folly::makeBitIterator(), and wheel_.

Referenced by cancelTimeout(), and getTimeRemaining().

                                              {
   if (--wheel_->count_ <= 0) {
     assert(wheel_->count_ == 0);
     wheel_->AsyncTimeout::cancelTimeout();
   }
   unlink();
   if ((-1 != bucket_) && (wheel_->buckets_[0][bucket_].empty())) {
     auto bi = makeBitIterator(wheel_->bitmap_.begin());
     *(bi + bucket_) = false;
   }
 
   wheel_ = nullptr;
   expiration_ = {};
 }

virtual std::chrono::steady_clock::time_point folly::HHWheelTimer::Callback::getCurTime ( )

inlineprotectedvirtual

Don't override this unless you're doing a test. This is mainly here so that we can override it to simulate lag in steady_clock.

Definition at line 121 of file HHWheelTimer.h.

References now().

Referenced by getTimeRemaining(), and setScheduled().

                                                          {
       return std::chrono::steady_clock::now();
     }

std::chrono::milliseconds folly::HHWheelTimer::Callback::getTimeRemaining ( )

inline

Get the time remaining until this timeout expires. Return 0 if this timeout is not scheduled or expired. Otherwise, return expiration time minus getCurTime().

Definition at line 112 of file HHWheelTimer.h.

References getCurTime().

                                              {
       return getTimeRemaining(getCurTime());
     }

std::chrono::milliseconds folly::HHWheelTimer::Callback::getTimeRemaining ( std::chrono::steady_clock::time_point now ) const

inlineprivate

Definition at line 127 of file HHWheelTimer.h.

References cancelTimeoutImpl(), expiration_, now(), and setScheduled().

                                                    {
       if (now >= expiration_) {
         return std::chrono::milliseconds(0);
       }
       return std::chrono::duration_cast<std::chrono::milliseconds>(
           expiration_ - now);
     }

bool folly::HHWheelTimer::Callback::isScheduled ( ) const

inline

Return true if this timeout is currently scheduled, and false otherwise.

Definition at line 103 of file HHWheelTimer.h.

References wheel_.

Referenced by proxygen::HTTPSession::detach(), proxygen::HTTPUpstreamSession::isReusable(), proxygen::HTTPSession::onConnectionSendWindowClosed(), proxygen::HTTPSession::onWriteSuccess(), proxygen::HTTPSession::runLoopCallback(), proxygen::HTTPSession::shutdownTransport(), ~Callback(), proxygen::HTTPSession::~HTTPSession(), and proxygen::HTTPTransaction::~HTTPTransaction().

                              {
       return wheel_ != nullptr;
     }

void Callback::setScheduled	(	HHWheelTimer *	wheel,
		std::chrono::milliseconds	timeout
	)

private

Definition at line 52 of file HHWheelTimer.cpp.

References expiration_, getCurTime(), and wheel_.

Referenced by getTimeRemaining(), and folly::HHWheelTimer::scheduleTimeout().

                                    {
   assert(wheel_ == nullptr);
   assert(expiration_ == decltype(expiration_){});
 
   wheel_ = wheel;
 
   expiration_ = getCurTime() + timeout;
 }