bloom.h

/*
 * Copyright (c) 2014  Wu, Xingbo <wuxb45@gmail.com>
 *
 * All rights reserved. No warranty, explicit or implicit, provided.
 */
#pragma once

#include <stdbool.h>
#include <stdio.h>
#include <stdint.h>

#include "mempool.h"
#include "stat.h"

struct BloomFilter {
  uint32_t bytes; // bytes = bits >> 3 (length of filter)
  uint32_t nr_keys;
  uint8_t filter[];
};

// compact bloom_table
// format: encoded bits, bits
#define BLOOMTABLE_INTERVAL ((16u))
struct BloomTable {
  uint8_t *raw_bf;
  uint32_t nr_bf;
  uint32_t nr_bytes; // size of raw_bf
  uint32_t offsets[];
};

// Container: storing boxes for multiple tables
// Box: multiple related bloom-filter in one box
struct BloomContainer {
  int raw_fd;
  uint64_t off_raw;       // === off_main in MetaFileHeader
  uint32_t nr_barrels;    // === nr_main
  uint32_t nr_bf_per_box; // 1 -- 8
  uint32_t nr_index;
  uint64_t mtid;
  uint16_t index_last[];       // the LAST barrel_id in each box
};

struct BloomFilter *
bloom_create(const uint32_t nr_keys, struct Mempool * const mempool);

void
bloom_update(struct BloomFilter * const bf, const uint64_t hv);

bool
bloom_match(const struct BloomFilter * const bf, const uint64_t hv);

struct BloomTable *
bloomtable_build(struct BloomFilter * const * const bfs, const uint64_t nr_bf);

bool
bloomtable_dump(struct BloomTable * const bt, FILE *fo);

struct BloomTable *
bloomtable_load(FILE * const fi);

bool
bloomtable_match(struct BloomTable * const bt, const uint32_t index, const uint64_t hv);

void
bloomtable_free(struct BloomTable * const bt);

struct BloomContainer *
bloomcontainer_build(struct BloomTable * const bt, const int raw_fd,
    const uint64_t off_raw, struct Stat * const stat);

struct BloomContainer *
bloomcontainer_update(struct BloomContainer * const bc, struct BloomTable * const bt,
    const int new_raw_fd, const uint64_t new_off_raw, struct Stat * const stat);

bool
bloomcontainer_dump_meta(struct BloomContainer * const bc, FILE * const fo);

struct BloomContainer *
bloomcontainer_load_meta(FILE * const fi, const int raw_fd);

uint64_t
bloomcontainer_match(struct BloomContainer * const bc, const uint32_t index, const uint64_t hv);

void
bloomcontainer_free(struct BloomContainer *const bc);