isc::asiolink::IntervalTimer Class Reference

The IntervalTimer class is a wrapper for the ASIO boost::asio::deadline_timer class. More...

#include <interval_timer.h>

Public Types
The type of timer callback function
enum	Mode { REPEATING, ONE_SHOT }
	Defines possible timer modes used to setup a timer. More...
typedef std::function< void()>	Callback

Public Member Functions
void	cancel ()
	Cancel the timer. More...
long	getInterval () const
	Return the timer interval. More...
void	setup (const Callback &cbfunc, const long interval, const Mode &mode=REPEATING)
	Register timer callback function and interval. More...

Constructors and Destructor
Note: The copy constructor and the assignment operator are intentionally defined as private, making this class non-copyable.
	IntervalTimer (IOService &io_service)
	The constructor with IOService. More...
	~IntervalTimer ()
	The destructor. More...

Detailed Description

The IntervalTimer class is a wrapper for the ASIO boost::asio::deadline_timer class.

This class is implemented to use boost::asio::deadline_timer as interval timer.

setup() sets a timer to expire on (now + interval), a call back function, and an interval mode.

IntervalTimerImpl::callback() is called by the timer when it expires.

The function calls the call back function set by setup() and if the the interval mode indicates a repeating interval, will reschedule the timer to expire in (now + interval) milliseconds.

The type of call back function is void(void).

The call back function will not be called if the instance of this class is destroyed before the timer is expired.

Sample code:

void function_to_call_back() {
    // this function will be called periodically
}
int interval_in_milliseconds = 1000;
IOService io_service;

IntervalTimer intervalTimer(io_service);
intervalTimer.setup(function_to_call_back, interval_in_milliseconds);
io_service.run();

Definition at line 52 of file interval_timer.h.

Member Typedef Documentation

typedef std::function<void()> isc::asiolink::IntervalTimer::Callback

Definition at line 55 of file interval_timer.h.

Member Enumeration Documentation

enum isc::asiolink::IntervalTimer::Mode

Defines possible timer modes used to setup a timer.

• REPEATING - Timer will reschedule itself after each expiration
• ONE_SHOT - Timer will expire after one interval and not reschedule.

Enumerator
REPEATING
ONE_SHOT

Definition at line 60 of file interval_timer.h.

Constructor & Destructor Documentation

isc::asiolink::IntervalTimer::IntervalTimer

(

IOService &

io_service

)

The constructor with IOService.

This constructor may throw a standard exception if memory allocation fails inside the method. This constructor may also throw boost::system::system_error.

Parameters

io_service

A reference to an instance of IOService

Definition at line 175 of file interval_timer.cc.

isc::asiolink::IntervalTimer::~IntervalTimer

(

)

The destructor.

This destructor never throws an exception.

On the destruction of this class the timer will be canceled inside boost::asio::deadline_timer.

Definition at line 179 of file interval_timer.cc.

References cancel().

Here is the call graph for this function:

Member Function Documentation

void isc::asiolink::IntervalTimer::cancel

(

)

Cancel the timer.

If the timer has been set up, this method cancels any asynchronous events waiting on the timer and stops the timer itself. If the timer has already been canceled, this method effectively does nothing.

This method never throws an exception.

Definition at line 191 of file interval_timer.cc.

Referenced by isc::http::HttpConnection::close(), isc::http::HttpConnection::shutdown(), isc::http::HttpConnection::socketReadCallback(), and ~IntervalTimer().

long isc::asiolink::IntervalTimer::getInterval

(

)

const

Return the timer interval.

This method returns the timer interval in milliseconds if it's running; if the timer has been canceled it returns 0.

This method never throws an exception.

Definition at line 196 of file interval_timer.cc.

void isc::asiolink::IntervalTimer::setup	(	const Callback &	cbfunc,
		const long	interval,
		const Mode &	mode = REPEATING
	)

Register timer callback function and interval.

This function sets callback function and interval in milliseconds. Timer will actually start after calling IOService::run().

Parameters

cbfunc	A reference to a function void(void) to call back when the timer is expired (should not be an empty functor)
interval	Interval in milliseconds (greater than 0)
mode	Determines if the timer will automatically reschedule after each expiration (the default) or behave as a one-shot which will run for a single interval and not reschedule.

Note: IntervalTimer will not pass boost::system::error_code to call back function. In case the timer is canceled, the function will not be called.

Exceptions

isc::InvalidParameter	cbfunc is empty
isc::BadValue	interval is less than or equal to 0
isc::Unexpected	internal runtime error

Definition at line 185 of file interval_timer.cc.

Referenced by isc::config::ClientConnectionImpl::scheduleTimer(), isc::http::HttpConnection::setupIdleTimer(), and isc::http::HttpConnection::setupRequestTimer().

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

• interval_timer.h
• interval_timer.cc