You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
39 lines
1.1 KiB
39 lines
1.1 KiB
/*
|
|
* UCW Library -- Rate Limiting based on the Token Bucket Filter
|
|
*
|
|
* (c) 2009 Martin Mares <mj@ucw.cz>
|
|
*
|
|
* This software may be freely distributed and used according to the terms
|
|
* of the GNU Lesser General Public License.
|
|
*/
|
|
|
|
#ifndef _UCW_TBF_H_
|
|
#define _UCW_TBF_H_
|
|
|
|
#ifdef CONFIG_UCW_CLEAN_ABI
|
|
#define tbf_init ucw_tbf_init
|
|
#define tbf_limit ucw_tbf_limit
|
|
#endif
|
|
|
|
/** A data structure describing a single TBF. **/
|
|
struct token_bucket_filter {
|
|
double rate; // Number of tokens received per second
|
|
uint burst; // Capacity of the bucket
|
|
timestamp_t last_hit; // Internal state...
|
|
double bucket;
|
|
uint drop_count;
|
|
};
|
|
|
|
/** Initialize the bucket. **/
|
|
void tbf_init(struct token_bucket_filter *f);
|
|
|
|
/**
|
|
* Ask the filter to process a single event. Returns a negative number
|
|
* if the event exceeds the rate (and should be dropped) and a non-negative
|
|
* number if the event passes the filter.
|
|
* The absolute value of the result is the number of dropped events
|
|
* since the last passed event.
|
|
**/
|
|
int tbf_limit(struct token_bucket_filter *f, timestamp_t now);
|
|
|
|
#endif
|
|
|