Detailed Description

Functional interface of a request.

Since all library I/O operations are asynchronous, one needs to keep track of their status: e.g. whether an I/O operation completed or not.

Definition at line 34 of file request_interface.hpp.

Inheritance diagram for request_interface:

#include <request_interface.hpp>

Public Types
using	offset_type = uint64_t
	type for offsets within a file More...

enum	read_or_write { READ, WRITE }

using	size_type = size_t
	type for block transfer sizes More...

Public Member Functions
	request_interface ()=default

	request_interface (const request_interface &)=delete
	non-copyable: delete copy-constructor More...

virtual	~request_interface ()

virtual bool	add_waiter (onoff_switch *sw)=0

virtual bool	cancel ()=0
	Cancel a request. More...

virtual void	delete_waiter (onoff_switch *sw)=0

virtual const char *	io_type () const =0
	Identifies the type of I/O implementation. More...

request_interface &	operator= (const request_interface &)=delete
	non-copyable: delete assignment operator More...

virtual bool	poll ()=0

virtual std::ostream &	print (std::ostream &out) const =0
	Dumps properties of a request. More...

virtual void	wait (bool measure_time=true)=0
	Suspends calling thread until completion of the request. More...

Protected Member Functions
virtual void	completed (bool canceled)=0

virtual void	notify_waiters ()=0

Member Typedef Documentation

◆ offset_type

using offset_type = uint64_t

type for offsets within a file

Definition at line 38 of file request_interface.hpp.

◆ size_type

using size_type = size_t

type for block transfer sizes

Definition at line 40 of file request_interface.hpp.

Member Enumeration Documentation

◆ read_or_write

enum read_or_write

Enumerator
READ
WRITE

Definition at line 42 of file request_interface.hpp.

Constructor & Destructor Documentation

◆ request_interface() [1/2]

request_interface ( )

default

◆ request_interface() [2/2]

request_interface ( const request_interface & )

delete

non-copyable: delete copy-constructor

◆ ~request_interface()

virtual ~request_interface ( )

inlinevirtual

Definition at line 62 of file request_interface.hpp.

References request_interface::cancel(), request_interface::io_type(), request_interface::poll(), request_interface::print(), and request_interface::wait().

Member Function Documentation

◆ add_waiter()

virtual bool add_waiter ( onoff_switch * sw )

pure virtual

Implemented in request_with_waiters.

◆ cancel()

virtual bool cancel ( )

pure virtual

Cancel a request.

The request is canceled unless already being processed. However, cancelation cannot be guaranteed. Canceled requests must still be waited for in order to ensure correct operation. If the request was canceled successfully, the completion handler will not be called.