folly::AsyncIOQueue Class Reference

#include <AsyncIO.h>

Public Types
typedef std::function< AsyncIOOp *()>	OpFactory

Public Member Functions
	AsyncIOQueue (AsyncIO *asyncIO)
	~AsyncIOQueue ()
size_t	queued () const
void	submit (AsyncIOOp *op)
void	submit (OpFactory op)

Private Member Functions
void	onCompleted (AsyncIOOp *op)
void	maybeDequeue ()

Private Attributes
AsyncIO *	asyncIO_
std::deque< OpFactory >	queue_

Detailed Description

Wrapper around AsyncIO that allows you to schedule more requests than the AsyncIO's object capacity. Other requests are queued and processed in a FIFO order.

Definition at line 242 of file AsyncIO.h.

Member Typedef Documentation

typedef std::function<AsyncIOOp*()> folly::AsyncIOQueue::OpFactory

Submit a delayed op to the AsyncIO queue; this allows you to postpone creation of the Op (which may require allocating memory, etc) until the AsyncIO object has room.

Definition at line 267 of file AsyncIO.h.

Constructor & Destructor Documentation

folly::AsyncIOQueue::AsyncIOQueue ( AsyncIO *  asyncIO )

explicit

Create a queue, using the given AsyncIO object. The AsyncIO object may not be used by anything else until the queue is destroyed.

Definition at line 276 of file AsyncIO.cpp.

: asyncIO_(asyncIO) {}

folly::AsyncIOQueue::~AsyncIOQueue

(

)

Definition at line 278 of file AsyncIO.cpp.

References asyncIO_, and folly::AsyncIO::pending().

                            {
  CHECK_EQ(asyncIO_->pending(), 0);
}

Member Function Documentation

void folly::AsyncIOQueue::maybeDequeue ( )

private

Definition at line 295 of file AsyncIO.cpp.

References asyncIO_, folly::AsyncIO::capacity(), onCompleted(), folly::AsyncIO::pending(), queue_, and folly::AsyncIO::submit().

Referenced by onCompleted(), and submit().

                                {
  while (!queue_.empty() && asyncIO_->pending() < asyncIO_->capacity()) {
    auto& opFactory = queue_.front();
    auto op = opFactory();
    queue_.pop_front();

    // Interpose our completion callback
    auto& nextCb = op->notificationCallback();
    op->setNotificationCallback([this, nextCb](AsyncIOOp* op2) {
      this->onCompleted(op2);
      if (nextCb) {
        nextCb(op2);
      }
    });

    asyncIO_->submit(op);
  }
}

void folly::AsyncIOQueue::onCompleted ( AsyncIOOp *  op )

private

Definition at line 291 of file AsyncIO.cpp.

References maybeDequeue().

Referenced by maybeDequeue().

                                           {
  maybeDequeue();
}

size_t folly::AsyncIOQueue::queued ( ) const

inline

Definition at line 252 of file AsyncIO.h.

References submit.

                        {
    return queue_.size();
  }

void folly::AsyncIOQueue::submit

(

AsyncIOOp *

op

)

Submit an op to the AsyncIO queue. The op will be queued until the AsyncIO object has room.

Definition at line 282 of file AsyncIO.cpp.

                                       {
  submit([op]() { return op; });
}

void folly::AsyncIOQueue::submit

(

OpFactory

op

)

Definition at line 286 of file AsyncIO.cpp.

References maybeDequeue(), and queue_.

                                      {
  queue_.push_back(op);
  maybeDequeue();
}

Member Data Documentation

AsyncIO* folly::AsyncIOQueue::asyncIO_

private

Definition at line 274 of file AsyncIO.h.

Referenced by maybeDequeue(), and ~AsyncIOQueue().

std::deque<OpFactory> folly::AsyncIOQueue::queue_

private

Definition at line 276 of file AsyncIO.h.

Referenced by maybeDequeue(), and submit().

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The documentation for this class was generated from the following files:

• proxygen/folly/folly/experimental/io/AsyncIO.h
• proxygen/folly/folly/experimental/io/AsyncIO.cpp