Token bucket rate template. More...

#include <click/tokenbucket.hh>

Inherits P.

Public Types
enum	{ max_tokens = (token_type) -1 }

typedef P	parameter_type
	The template parameter type.

typedef P::token_type	token_type
	Unsigned type of token counts.

typedef P::time_point_type	time_point_type
	Type of time points.

typedef make_unsigned< typenameP::duration_type >::type	ticks_type
	Unsigned type of tick counts (differences between time points).

Public Member Functions
	TokenRateX ()
	Construct an idle token rate.

	TokenRateX (bool unlimited)
	Construct an idle or unlimited token rate.

	TokenRateX (token_type rate, token_type capacity)
	Construct a token rate representing rate.

void	assign (bool unlimited=false)
	Set the token rate to idle or unlimited.

void	assign (token_type rate, token_type capacity)
	Set the token rate and capacity.

bool	unlimited () const
	Return true iff the token rate is unlimited.

bool	idle () const
	Return true iff the token rate is idle.

token_type	rate () const
	Return the rate in tokens per period.

token_type	capacity () const
	Return the capacity in tokens.

token_type	tokens_per_tick () const
	Return the number of tokens per tick.

token_type	token_scale () const
	Return the ratio of fractional tokens to real tokens.

ticks_type	time_until_full () const
	Return the number of ticks required to refill a counter to capacity.

time_point_type	now () const
	Return the current time point.

template<typename U >
time_point_type	time_point (U time) const
	Return the time point corresponding to the time parameter.

ticks_type	time_monotonic_difference (time_point_type a, time_point_type b) const
	Return b - a, assuming that b was measured after a.

Detailed Description

template<typename P>
class TokenRateX

Token bucket rate template.

The TokenRateX class implements a token bucket rate. TokenBucketX is initialized with a rate, in tokens per second, and a capacity in tokens. Associated token buckets fill up with tokens at the given rate, to a maximum of the capacity.

Two special types of rate are supported. An unlimited TokenRateX always refills associated counters to full capacity. Its capacity() equals token_max. An idle TokenRateX never refills.

Most users will be satisfied with the TokenRate type, which is equal to TokenRateX<TokenBucketUsecParameters<unsigned long long> >.

See also: TokenCounterX, TokenBucketX

Member Typedef Documentation

◆ parameter_type

template<typename P >

typedef P TokenRateX::parameter_type

The template parameter type.

◆ token_type

template<typename P >

typedef P::token_type TokenRateX::token_type

Unsigned type of token counts.

◆ time_point_type

template<typename P >

typedef P::time_point_type TokenRateX::time_point_type

Type of time points.

◆ ticks_type

template<typename P >

typedef make_unsigned<typenameP::duration_type>::type TokenRateX::ticks_type

Unsigned type of tick counts (differences between time points).

Constructor & Destructor Documentation

◆ TokenRateX() [1/3]

template<typename P >

TokenRateX::TokenRateX ( )

inline

Construct an idle token rate.

◆ TokenRateX() [2/3]

template<typename P >

TokenRateX::TokenRateX ( bool unlimited )

inlineexplicit

Construct an idle or unlimited token rate.

Parameters

unlimited idle if false, unlimited if true

◆ TokenRateX() [3/3]

template<typename P >

TokenRateX< P >::TokenRateX	(	token_type	rate,
		token_type	capacity
	)

inline

Construct a token rate representing rate.

Parameters

rate	refill rate in tokens per period
capacity	maximum token accumulation

The rate is idle if either rate or capacity is 0.

See also: assign(rate, capacity)

Member Function Documentation

◆ assign() [1/2]

template<typename P >

void TokenRateX::assign ( bool unlimited = false )

inline

Set the token rate to idle or unlimited.

Parameters

unlimited idle if false, unlimited if true

◆ assign() [2/2]

template<typename P >

void TokenRateX< P >::assign	(	token_type	rate,
		token_type	capacity
	)

inline

Set the token rate and capacity.

Parameters

rate	refill rate in tokens per period
capacity	maximum token accumulation

Sets the token bucket's rate to rate and capacity to capacity. If either rate or capacity is 0, the rate becomes idle.

◆ unlimited()

template<typename P >

bool TokenRateX::unlimited ( ) const

inline

Return true iff the token rate is unlimited.

◆ idle()

template<typename P >

bool TokenRateX::idle ( ) const

inline

Return true iff the token rate is idle.

◆ rate()

template<typename P >

P::token_type TokenRateX::rate ( ) const

Return the rate in tokens per period.

Returns max_tokens for unlimited rates. Imprecise computer arithmetic may cause the result to differ from the configured rate.

◆ capacity()

template<typename P >

token_type TokenRateX::capacity ( ) const

inline

Return the capacity in tokens.

Returns max_tokens for unlimited rates. Imprecise computer arithmetic may cause the result to differ from the configured capacity.

◆ tokens_per_tick()

template<typename P >

token_type TokenRateX::tokens_per_tick ( ) const

inline

Return the number of tokens per tick.

◆ token_scale()

template<typename P >

token_type TokenRateX::token_scale ( ) const

inline

Return the ratio of fractional tokens to real tokens.

◆ time_until_full()

template<typename P >

ticks_type TokenRateX::time_until_full ( ) const

inline

Return the number of ticks required to refill a counter to capacity.

Returns (ticks_type) -1 for idle rates.

◆ now()

template<typename P >

time_point_type TokenRateX::now ( ) const

inline

Return the current time point.

Implemented as P::now().

◆ time_point()

template<typename P >

template<typename U >

time_point_type TokenRateX::time_point ( U time ) const

inline

Return the time point corresponding to the time parameter.

May not be available for all U types. Implemented as P::time_point(time).

◆ time_monotonic_difference()

template<typename P >

ticks_type TokenRateX< P >::time_monotonic_difference	(	time_point_type	a,
		time_point_type	b
	)		const

inline

Return b - a, assuming that b was measured after a.

Some time measurements can, in rare cases, appear to jump backwards, as timestamps do when the user changes the current time. If this happens (b < a), time_monotonic_difference returns 0. Implemented as P::time_monotonic_difference(a, b).

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

include/click/tokenbucket.hh

Public Types

Public Member Functions

Detailed Description

Member Typedef Documentation

◆ parameter_type

◆ token_type

◆ time_point_type

◆ ticks_type

Constructor & Destructor Documentation

◆ TokenRateX() [1/3]

◆ TokenRateX() [2/3]

◆ TokenRateX() [3/3]

Member Function Documentation

◆ assign() [1/2]

◆ assign() [2/2]

◆ unlimited()

◆ idle()

◆ rate()

◆ capacity()

◆ tokens_per_tick()

◆ token_scale()

◆ time_until_full()

◆ now()

◆ time_point()

◆ time_monotonic_difference()