mirror of
https://github.com/netsurf-browser/netsurf
synced 2024-11-22 14:31:20 +03:00
100 lines
2.7 KiB
C
100 lines
2.7 KiB
C
/*
|
|
* Copyright 2013 Rob Kendrick <rjek@netsurf-browser.org>
|
|
*
|
|
* This file is part of NetSurf, http://www.netsurf-browser.org/
|
|
*
|
|
* NetSurf is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License as published by
|
|
* the Free Software Foundation; version 2 of the License.
|
|
*
|
|
* NetSurf is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with this program. If not, see <http://www.gnu.org/licenses/>.
|
|
*/
|
|
|
|
/** \file
|
|
* Trivial bloom filter */
|
|
|
|
#ifndef _NETSURF_UTILS_BLOOM_H_
|
|
#define _NETSURF_UTILS_BLOOM_H_
|
|
|
|
#include <stdbool.h>
|
|
#include <stddef.h>
|
|
#include <stdint.h>
|
|
|
|
struct bloom_filter;
|
|
|
|
/**
|
|
* Create a new bloom filter.
|
|
*
|
|
* \param size Size of bloom filter in bytes
|
|
* \return Handle for newly-created bloom filter, or NULL
|
|
*/
|
|
struct bloom_filter *bloom_create(size_t size);
|
|
|
|
/**
|
|
* Destroy a previously-created bloom filter
|
|
*
|
|
* \param b Bloom filter to destroy
|
|
*/
|
|
void bloom_destroy(struct bloom_filter *b);
|
|
|
|
/**
|
|
* Insert a string of given length (may include NULs) into the filter,
|
|
* using an internal hash function.
|
|
*
|
|
* \param b Bloom filter to add to
|
|
* \param s Pointer to data
|
|
* \param z Length of data
|
|
*/
|
|
void bloom_insert_str(struct bloom_filter *b, const char *s, size_t z);
|
|
|
|
/**
|
|
* Insert a given hash value into the filter, should you already have
|
|
* one to hand.
|
|
*
|
|
* \param b Bloom filter to add to
|
|
* \param hash Value to add
|
|
*/
|
|
void bloom_insert_hash(struct bloom_filter *b, uint32_t hash);
|
|
|
|
/**
|
|
* Search the filter for the given string, assuming it was added by
|
|
* bloom_insert_str(). May return false-positives.
|
|
*
|
|
* \param b Bloom filter to search
|
|
* \param s Pointer to data to search for
|
|
* \param z Length of data
|
|
*
|
|
* \return False if never added, True if it might have been.
|
|
*/
|
|
bool bloom_search_str(struct bloom_filter *b, const char *s, size_t z);
|
|
|
|
/**
|
|
* Search the filter for the given hash value, assuming it was added by
|
|
* bloom_insert_hash(). May return false-positives.
|
|
*
|
|
* \param b Bloom filter to search
|
|
* \param hash Hash value to search for
|
|
*
|
|
* \return False if never added, True if it might have been.
|
|
*/
|
|
bool bloom_search_hash(struct bloom_filter *b, uint32_t hash);
|
|
|
|
/**
|
|
* Find out how many items have been added to this bloom filter. This
|
|
* is useful for deciding the size of a new bloom filter should you
|
|
* need to rehash it.
|
|
*
|
|
* \param b Bloom filter to examine
|
|
*
|
|
* \return Number of items that have been added
|
|
*/
|
|
uint32_t bloom_items(struct bloom_filter *b);
|
|
|
|
#endif
|