dopen.c

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/* This file is part of the Zebra server.
   Copyright (C) Index Data
 
Zebra 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; either version 2, or (at your option) any later
version.
 
Zebra 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, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 
*/
 
 
 
#if HAVE_CONFIG_H
#include <config.h>
#endif
#include <sys/types.h>
#include <fcntl.h>
#if HAVE_UNISTD_H
#include <unistd.h>
#endif
#include <stdio.h>
#include <stdlib.h>
 
#include "dict-p.h"
 
static void common_init(Dict_BFile bf, int block_size, int cache)
{
    int i;
 
    bf->block_size = block_size;
    bf->compact_flag = 0;
    bf->cache = cache;
    bf->hash_size = 31;
 
    bf->hits = bf->misses = 0;
 
    /* Allocate all blocks in one chunk. */
    bf->all_data = xmalloc(block_size * cache);
 
    /* Allocate and initialize hash array (as empty) */
    bf->hash_array = (struct Dict_file_block **)
        xmalloc(sizeof(*bf->hash_array) * bf->hash_size);
    for (i=bf->hash_size; --i >= 0; )
        bf->hash_array[i] = NULL;
 
    /* Allocate all block descriptors in one chunk */
    bf->all_blocks = (struct Dict_file_block *)
        xmalloc(sizeof(*bf->all_blocks) * cache);
 
    /* Initialize the free list */
    bf->free_list = bf->all_blocks;
    for (i=0; i<cache-1; i++)
        bf->all_blocks[i].h_next = bf->all_blocks+(i+1);
    bf->all_blocks[i].h_next = NULL;
 
    /* Initialize the data for each block. Will never be moved again */
    for (i=0; i<cache; i++)
        bf->all_blocks[i].data = (char*) bf->all_data + i*block_size;
 
    /* Initialize lru queue */
    bf->lru_back = NULL;
    bf->lru_front = NULL;
}
 
 
Dict_BFile dict_bf_open(BFiles bfs, const char *name, int block_size,
                        int cache, int rw)
{
    Dict_BFile dbf;
 
    dbf = (Dict_BFile) xmalloc(sizeof(*dbf));
    dbf->bf = bf_open(bfs, name, block_size, rw);
    if (!dbf->bf)
    {
        xfree(dbf);
        return 0;
    }
    common_init(dbf, block_size, cache);
    return dbf;
}
 
void dict_bf_compact(Dict_BFile dbf)
{
    dbf->compact_flag = 1;
}
/*
 * Local variables:
 * c-basic-offset: 4
 * c-file-style: "Stroustrup"
 * indent-tabs-mode: nil
 * End:
 * vim: shiftwidth=4 tabstop=8 expandtab
 */