git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@578 65c4cc65-6c06-0410-ace0-fbb531ad65f3
1000 lines
24 KiB
C
Executable file
1000 lines
24 KiB
C
Executable file
/*-
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* Copyright (c) 1990, 1993, 1994
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* The Regents of the University of California. All rights reserved.
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*
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* This code is derived from software contributed to Berkeley by
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* Margo Seltzer.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* 3. All advertising materials mentioning features or use of this software
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* must display the following acknowledgement:
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* This product includes software developed by the University of
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* California, Berkeley and its contributors.
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* 4. Neither the name of the University nor the names of its contributors
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* may be used to endorse or promote products derived from this software
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* without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*/
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#if defined(LIBC_SCCS) && !defined(lint)
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static char sccsid[] = "@(#)hash.c 8.9 (Berkeley) 6/16/94";
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#endif /* LIBC_SCCS and not lint */
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#include <sys/param.h>
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#include <sys/stat.h>
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#include <errno.h>
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#include <fcntl.h>
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#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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#include <unistd.h>
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#ifdef DEBUG
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#include <assert.h>
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#endif
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#include <db.h>
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#include "hash.h"
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#include "page.h"
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#include "extern.h"
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static int alloc_segs __P((HTAB *, int));
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static int flush_meta __P((HTAB *));
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static int hash_access __P((HTAB *, ACTION, DBT *, DBT *));
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static int hash_close __P((DB *));
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static int hash_delete __P((const DB *, const DBT *, u_int32_t));
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static int hash_fd __P((const DB *));
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static int hash_get __P((const DB *, const DBT *, DBT *, u_int32_t));
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static int hash_put __P((const DB *, DBT *, const DBT *, u_int32_t));
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static void *hash_realloc __P((SEGMENT **, int, int));
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static int hash_seq __P((const DB *, DBT *, DBT *, u_int32_t));
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static int hash_sync __P((const DB *, u_int32_t));
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static int hdestroy __P((HTAB *));
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static HTAB *init_hash __P((HTAB *, const char *, HASHINFO *));
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static int init_htab __P((HTAB *, int));
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#if BYTE_ORDER == LITTLE_ENDIAN
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static void swap_header __P((HTAB *));
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static void swap_header_copy __P((HASHHDR *, HASHHDR *));
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#endif
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/* Fast arithmetic, relying on powers of 2, */
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#define MOD(x, y) ((x) & ((y) - 1))
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#define RETURN_ERROR(ERR, LOC) { save_errno = ERR; goto LOC; }
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/* Return values */
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#define SUCCESS (0)
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#define ERROR (-1)
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#define ABNORMAL (1)
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#ifdef HASH_STATISTICS
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int hash_accesses, hash_collisions, hash_expansions, hash_overflows;
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#endif
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/************************** INTERFACE ROUTINES ***************************/
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/* OPEN/CLOSE */
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extern DB *
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__hash_open(file, flags, mode, info, dflags)
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const char *file;
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int flags, mode, dflags;
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const HASHINFO *info; /* Special directives for create */
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{
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HTAB *hashp;
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struct stat statbuf;
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DB *dbp;
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int bpages, hdrsize, new_table, nsegs, save_errno;
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if ((flags & O_ACCMODE) == O_WRONLY) {
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errno = EINVAL;
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return (NULL);
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}
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if (!(hashp = (HTAB *)calloc(1, sizeof(HTAB))))
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return (NULL);
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hashp->fp = -1;
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/*
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* Even if user wants write only, we need to be able to read
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* the actual file, so we need to open it read/write. But, the
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* field in the hashp structure needs to be accurate so that
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* we can check accesses.
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*/
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hashp->flags = flags;
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new_table = 0;
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if (!file || (flags & O_TRUNC) ||
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(stat(file, &statbuf) && (errno == ENOENT))) {
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if (errno == ENOENT)
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errno = 0; /* Just in case someone looks at errno */
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new_table = 1;
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}
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if (file) {
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if ((hashp->fp = open(file, flags, mode)) == -1)
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RETURN_ERROR(errno, error0);
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(void)fcntl(hashp->fp, F_SETFD, 1);
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}
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if (new_table) {
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if (!(hashp = init_hash(hashp, file, (HASHINFO *)info)))
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RETURN_ERROR(errno, error1);
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} else {
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/* Table already exists */
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if (info && info->hash)
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hashp->hash = info->hash;
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else
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hashp->hash = __default_hash;
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hdrsize = read(hashp->fp, &hashp->hdr, sizeof(HASHHDR));
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#if BYTE_ORDER == LITTLE_ENDIAN
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swap_header(hashp);
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#endif
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if (hdrsize == -1)
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RETURN_ERROR(errno, error1);
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if (hdrsize != sizeof(HASHHDR))
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RETURN_ERROR(EFTYPE, error1);
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/* Verify file type, versions and hash function */
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if (hashp->MAGIC != HASHMAGIC)
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RETURN_ERROR(EFTYPE, error1);
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#define OLDHASHVERSION 1
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if (hashp->VERSION != HASHVERSION &&
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hashp->VERSION != OLDHASHVERSION)
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RETURN_ERROR(EFTYPE, error1);
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if (hashp->hash(CHARKEY, sizeof(CHARKEY))
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!= (u_int32_t) hashp->H_CHARKEY)
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RETURN_ERROR(EFTYPE, error1);
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/*
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* Figure out how many segments we need. Max_Bucket is the
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* maximum bucket number, so the number of buckets is
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* max_bucket + 1.
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*/
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nsegs = (hashp->MAX_BUCKET + 1 + hashp->SGSIZE - 1) /
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hashp->SGSIZE;
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hashp->nsegs = 0;
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if (alloc_segs(hashp, nsegs))
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/*
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* If alloc_segs fails, table will have been destroyed
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* and errno will have been set.
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*/
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return (NULL);
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/* Read in bitmaps */
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bpages = (hashp->SPARES[hashp->OVFL_POINT] +
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(hashp->BSIZE << BYTE_SHIFT) - 1) >>
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(hashp->BSHIFT + BYTE_SHIFT);
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hashp->nmaps = bpages;
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(void)memset(&hashp->mapp[0], 0, bpages * sizeof(u_int32_t *));
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}
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/* Initialize Buffer Manager */
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if (info && info->cachesize)
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__buf_init(hashp, info->cachesize);
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else
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__buf_init(hashp, DEF_BUFSIZE);
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hashp->new_file = new_table;
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hashp->save_file = file && (hashp->flags & O_ACCMODE) != O_RDONLY;
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hashp->cbucket = -1;
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if (!(dbp = (DB *)malloc(sizeof(DB)))) {
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save_errno = errno;
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hdestroy(hashp);
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errno = save_errno;
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return (NULL);
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}
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dbp->internal = hashp;
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dbp->close = hash_close;
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dbp->del = hash_delete;
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dbp->fd = hash_fd;
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dbp->get = hash_get;
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dbp->put = hash_put;
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dbp->seq = hash_seq;
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dbp->sync = hash_sync;
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dbp->type = DB_HASH;
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#ifdef DEBUG
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(void)fprintf(stderr,
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"%s\n%s%x\n%s%d\n%s%d\n%s%d\n%s%d\n%s%d\n%s%d\n%s%d\n%s%d\n%s%d\n%s%x\n%s%x\n%s%d\n%s%d\n",
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"init_htab:",
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"TABLE POINTER ", hashp,
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"BUCKET SIZE ", hashp->BSIZE,
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"BUCKET SHIFT ", hashp->BSHIFT,
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"DIRECTORY SIZE ", hashp->DSIZE,
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"SEGMENT SIZE ", hashp->SGSIZE,
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"SEGMENT SHIFT ", hashp->SSHIFT,
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"FILL FACTOR ", hashp->FFACTOR,
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"MAX BUCKET ", hashp->MAX_BUCKET,
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"OVFL POINT ", hashp->OVFL_POINT,
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"LAST FREED ", hashp->LAST_FREED,
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"HIGH MASK ", hashp->HIGH_MASK,
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"LOW MASK ", hashp->LOW_MASK,
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"NSEGS ", hashp->nsegs,
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"NKEYS ", hashp->NKEYS);
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#endif
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#ifdef HASH_STATISTICS
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hash_overflows = hash_accesses = hash_collisions = hash_expansions = 0;
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#endif
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return (dbp);
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error1:
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if (hashp != NULL)
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(void)close(hashp->fp);
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error0:
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free(hashp);
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errno = save_errno;
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return (NULL);
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}
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static int
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hash_close(dbp)
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DB *dbp;
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{
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HTAB *hashp;
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int retval;
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if (!dbp)
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return (ERROR);
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hashp = (HTAB *)dbp->internal;
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retval = hdestroy(hashp);
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free(dbp);
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return (retval);
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}
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static int
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hash_fd(dbp)
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const DB *dbp;
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{
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HTAB *hashp;
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if (!dbp)
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return (ERROR);
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hashp = (HTAB *)dbp->internal;
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if (hashp->fp == -1) {
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errno = ENOENT;
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return (-1);
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}
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return (hashp->fp);
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}
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/************************** LOCAL CREATION ROUTINES **********************/
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static HTAB *
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init_hash(hashp, file, info)
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HTAB *hashp;
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const char *file;
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HASHINFO *info;
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{
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#ifdef _STATBUF_ST_BLKSIZE
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struct stat statbuf;
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#endif
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int nelem;
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nelem = 1;
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hashp->NKEYS = 0;
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hashp->LORDER = BYTE_ORDER;
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hashp->BSIZE = DEF_BUCKET_SIZE;
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hashp->BSHIFT = DEF_BUCKET_SHIFT;
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hashp->SGSIZE = DEF_SEGSIZE;
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hashp->SSHIFT = DEF_SEGSIZE_SHIFT;
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hashp->DSIZE = DEF_DIRSIZE;
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hashp->FFACTOR = DEF_FFACTOR;
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hashp->hash = __default_hash;
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memset(hashp->SPARES, 0, sizeof(hashp->SPARES));
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memset(hashp->BITMAPS, 0, sizeof (hashp->BITMAPS));
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/* Fix bucket size to be optimal for file system */
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#ifdef _STATBUF_ST_BLKSIZE
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if (file != NULL) {
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if (stat(file, &statbuf))
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return (NULL);
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hashp->BSIZE = statbuf.st_blksize;
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hashp->BSHIFT = __hash_log2(hashp->BSIZE);
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}
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#endif
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if (info) {
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if (info->bsize) {
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/* Round pagesize up to power of 2 */
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hashp->BSHIFT = __hash_log2(info->bsize);
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hashp->BSIZE = 1 << hashp->BSHIFT;
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if (hashp->BSIZE > MAX_BSIZE) {
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errno = EINVAL;
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return (NULL);
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}
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}
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if (info->ffactor)
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hashp->FFACTOR = info->ffactor;
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if (info->hash)
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hashp->hash = info->hash;
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if (info->nelem)
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nelem = info->nelem;
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if (info->lorder) {
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if (info->lorder != BIG_ENDIAN &&
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info->lorder != LITTLE_ENDIAN) {
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errno = EINVAL;
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return (NULL);
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}
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hashp->LORDER = info->lorder;
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}
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}
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/* init_htab should destroy the table and set errno if it fails */
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if (init_htab(hashp, nelem))
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return (NULL);
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else
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return (hashp);
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}
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/*
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* This calls alloc_segs which may run out of memory. Alloc_segs will destroy
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* the table and set errno, so we just pass the error information along.
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*
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* Returns 0 on No Error
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*/
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static int
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init_htab(hashp, nelem)
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HTAB *hashp;
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int nelem;
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{
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register int nbuckets, nsegs;
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int l2;
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/*
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* Divide number of elements by the fill factor and determine a
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* desired number of buckets. Allocate space for the next greater
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* power of two number of buckets.
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*/
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nelem = (nelem - 1) / hashp->FFACTOR + 1;
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l2 = __hash_log2(MAX(nelem, 2));
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nbuckets = 1 << l2;
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hashp->SPARES[l2] = l2 + 1;
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hashp->SPARES[l2 + 1] = l2 + 1;
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hashp->OVFL_POINT = l2;
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hashp->LAST_FREED = 2;
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/* First bitmap page is at: splitpoint l2 page offset 1 */
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if (__ibitmap(hashp, OADDR_OF(l2, 1), l2 + 1, 0))
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return (-1);
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hashp->MAX_BUCKET = hashp->LOW_MASK = nbuckets - 1;
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hashp->HIGH_MASK = (nbuckets << 1) - 1;
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hashp->HDRPAGES = ((MAX(sizeof(HASHHDR), MINHDRSIZE) - 1) >>
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hashp->BSHIFT) + 1;
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nsegs = (nbuckets - 1) / hashp->SGSIZE + 1;
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nsegs = 1 << __hash_log2(nsegs);
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if (nsegs > hashp->DSIZE)
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hashp->DSIZE = nsegs;
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return (alloc_segs(hashp, nsegs));
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}
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/********************** DESTROY/CLOSE ROUTINES ************************/
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/*
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* Flushes any changes to the file if necessary and destroys the hashp
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* structure, freeing all allocated space.
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*/
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static int
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hdestroy(hashp)
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HTAB *hashp;
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{
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int i, save_errno;
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save_errno = 0;
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#ifdef HASH_STATISTICS
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(void)fprintf(stderr, "hdestroy: accesses %ld collisions %ld\n",
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hash_accesses, hash_collisions);
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(void)fprintf(stderr, "hdestroy: expansions %ld\n",
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hash_expansions);
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(void)fprintf(stderr, "hdestroy: overflows %ld\n",
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hash_overflows);
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(void)fprintf(stderr, "keys %ld maxp %d segmentcount %d\n",
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hashp->NKEYS, hashp->MAX_BUCKET, hashp->nsegs);
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for (i = 0; i < NCACHED; i++)
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(void)fprintf(stderr,
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"spares[%d] = %d\n", i, hashp->SPARES[i]);
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#endif
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/*
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* Call on buffer manager to free buffers, and if required,
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* write them to disk.
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*/
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if (__buf_free(hashp, 1, hashp->save_file))
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save_errno = errno;
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if (hashp->dir) {
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free(*hashp->dir); /* Free initial segments */
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/* Free extra segments */
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while (hashp->exsegs--)
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free(hashp->dir[--hashp->nsegs]);
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free(hashp->dir);
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}
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if (flush_meta(hashp) && !save_errno)
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save_errno = errno;
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/* Free Bigmaps */
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for (i = 0; i < hashp->nmaps; i++)
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if (hashp->mapp[i])
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free(hashp->mapp[i]);
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if (hashp->fp != -1)
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(void)close(hashp->fp);
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free(hashp);
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if (save_errno) {
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errno = save_errno;
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return (ERROR);
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}
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return (SUCCESS);
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}
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/*
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* Write modified pages to disk
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*
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* Returns:
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* 0 == OK
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* -1 ERROR
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*/
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static int
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hash_sync(dbp, flags)
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const DB *dbp;
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u_int32_t flags;
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{
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HTAB *hashp;
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if (flags != 0) {
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errno = EINVAL;
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return (ERROR);
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}
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if (!dbp)
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return (ERROR);
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hashp = (HTAB *)dbp->internal;
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if (!hashp->save_file)
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return (0);
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if (__buf_free(hashp, 0, 1) || flush_meta(hashp))
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return (ERROR);
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hashp->new_file = 0;
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return (0);
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}
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/*
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* Returns:
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* 0 == OK
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* -1 indicates that errno should be set
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*/
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static int
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flush_meta(hashp)
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HTAB *hashp;
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{
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HASHHDR *whdrp;
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#if BYTE_ORDER == LITTLE_ENDIAN
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HASHHDR whdr;
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#endif
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int fp, i, wsize;
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if (!hashp->save_file)
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return (0);
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hashp->MAGIC = HASHMAGIC;
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hashp->VERSION = HASHVERSION;
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hashp->H_CHARKEY = hashp->hash(CHARKEY, sizeof(CHARKEY));
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fp = hashp->fp;
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whdrp = &hashp->hdr;
|
|
#if BYTE_ORDER == LITTLE_ENDIAN
|
|
whdrp = &whdr;
|
|
swap_header_copy(&hashp->hdr, whdrp);
|
|
#endif
|
|
if ((lseek(fp, (off_t)0, SEEK_SET) == -1) ||
|
|
((wsize = write(fp, whdrp, sizeof(HASHHDR))) == -1))
|
|
return (-1);
|
|
else
|
|
if (wsize != sizeof(HASHHDR)) {
|
|
errno = EFTYPE;
|
|
hashp->errnum = errno;
|
|
return (-1);
|
|
}
|
|
for (i = 0; i < NCACHED; i++)
|
|
if (hashp->mapp[i])
|
|
if (__put_page(hashp, (char *)hashp->mapp[i],
|
|
hashp->BITMAPS[i], 0, 1))
|
|
return (-1);
|
|
return (0);
|
|
}
|
|
|
|
/*******************************SEARCH ROUTINES *****************************/
|
|
/*
|
|
* All the access routines return
|
|
*
|
|
* Returns:
|
|
* 0 on SUCCESS
|
|
* 1 to indicate an external ERROR (i.e. key not found, etc)
|
|
* -1 to indicate an internal ERROR (i.e. out of memory, etc)
|
|
*/
|
|
static int
|
|
hash_get(dbp, key, data, flag)
|
|
const DB *dbp;
|
|
const DBT *key;
|
|
DBT *data;
|
|
u_int32_t flag;
|
|
{
|
|
HTAB *hashp;
|
|
|
|
hashp = (HTAB *)dbp->internal;
|
|
if (flag) {
|
|
hashp->errnum = errno = EINVAL;
|
|
return (ERROR);
|
|
}
|
|
return (hash_access(hashp, HASH_GET, (DBT *)key, data));
|
|
}
|
|
|
|
static int
|
|
hash_put(dbp, key, data, flag)
|
|
const DB *dbp;
|
|
DBT *key;
|
|
const DBT *data;
|
|
u_int32_t flag;
|
|
{
|
|
HTAB *hashp;
|
|
|
|
hashp = (HTAB *)dbp->internal;
|
|
if (flag && flag != R_NOOVERWRITE) {
|
|
hashp->errnum = errno = EINVAL;
|
|
return (ERROR);
|
|
}
|
|
if ((hashp->flags & O_ACCMODE) == O_RDONLY) {
|
|
hashp->errnum = errno = EPERM;
|
|
return (ERROR);
|
|
}
|
|
return (hash_access(hashp, flag == R_NOOVERWRITE ?
|
|
HASH_PUTNEW : HASH_PUT, (DBT *)key, (DBT *)data));
|
|
}
|
|
|
|
static int
|
|
hash_delete(dbp, key, flag)
|
|
const DB *dbp;
|
|
const DBT *key;
|
|
u_int32_t flag; /* Ignored */
|
|
{
|
|
HTAB *hashp;
|
|
|
|
hashp = (HTAB *)dbp->internal;
|
|
if (flag && flag != R_CURSOR) {
|
|
hashp->errnum = errno = EINVAL;
|
|
return (ERROR);
|
|
}
|
|
if ((hashp->flags & O_ACCMODE) == O_RDONLY) {
|
|
hashp->errnum = errno = EPERM;
|
|
return (ERROR);
|
|
}
|
|
return (hash_access(hashp, HASH_DELETE, (DBT *)key, NULL));
|
|
}
|
|
|
|
/*
|
|
* Assume that hashp has been set in wrapper routine.
|
|
*/
|
|
static int
|
|
hash_access(hashp, action, key, val)
|
|
HTAB *hashp;
|
|
ACTION action;
|
|
DBT *key, *val;
|
|
{
|
|
register BUFHEAD *rbufp;
|
|
BUFHEAD *bufp, *save_bufp;
|
|
register u_int16_t *bp;
|
|
register int n, ndx, off, size;
|
|
register char *kp;
|
|
u_int16_t pageno;
|
|
|
|
#ifdef HASH_STATISTICS
|
|
hash_accesses++;
|
|
#endif
|
|
|
|
off = hashp->BSIZE;
|
|
size = key->size;
|
|
kp = (char *)key->data;
|
|
rbufp = __get_buf(hashp, __call_hash(hashp, kp, size), NULL, 0);
|
|
if (!rbufp)
|
|
return (ERROR);
|
|
save_bufp = rbufp;
|
|
|
|
/* Pin the bucket chain */
|
|
rbufp->flags |= BUF_PIN;
|
|
for (bp = (u_int16_t *)rbufp->page, n = *bp++, ndx = 1; ndx < n;)
|
|
if (bp[1] >= REAL_KEY) {
|
|
/* Real key/data pair */
|
|
if (size == off - *bp &&
|
|
memcmp(kp, rbufp->page + *bp, size) == 0)
|
|
goto found;
|
|
off = bp[1];
|
|
#ifdef HASH_STATISTICS
|
|
hash_collisions++;
|
|
#endif
|
|
bp += 2;
|
|
ndx += 2;
|
|
} else if (bp[1] == OVFLPAGE) {
|
|
rbufp = __get_buf(hashp, *bp, rbufp, 0);
|
|
if (!rbufp) {
|
|
save_bufp->flags &= ~BUF_PIN;
|
|
return (ERROR);
|
|
}
|
|
/* FOR LOOP INIT */
|
|
bp = (u_int16_t *)rbufp->page;
|
|
n = *bp++;
|
|
ndx = 1;
|
|
off = hashp->BSIZE;
|
|
} else if (bp[1] < REAL_KEY) {
|
|
if ((ndx =
|
|
__find_bigpair(hashp, rbufp, ndx, kp, size)) > 0)
|
|
goto found;
|
|
if (ndx == -2) {
|
|
bufp = rbufp;
|
|
if (!(pageno =
|
|
__find_last_page(hashp, &bufp))) {
|
|
ndx = 0;
|
|
rbufp = bufp;
|
|
break; /* FOR */
|
|
}
|
|
rbufp = __get_buf(hashp, pageno, bufp, 0);
|
|
if (!rbufp) {
|
|
save_bufp->flags &= ~BUF_PIN;
|
|
return (ERROR);
|
|
}
|
|
/* FOR LOOP INIT */
|
|
bp = (u_int16_t *)rbufp->page;
|
|
n = *bp++;
|
|
ndx = 1;
|
|
off = hashp->BSIZE;
|
|
} else {
|
|
save_bufp->flags &= ~BUF_PIN;
|
|
return (ERROR);
|
|
}
|
|
}
|
|
|
|
/* Not found */
|
|
switch (action) {
|
|
case HASH_PUT:
|
|
case HASH_PUTNEW:
|
|
if (__addel(hashp, rbufp, key, val)) {
|
|
save_bufp->flags &= ~BUF_PIN;
|
|
return (ERROR);
|
|
} else {
|
|
save_bufp->flags &= ~BUF_PIN;
|
|
return (SUCCESS);
|
|
}
|
|
case HASH_GET:
|
|
case HASH_DELETE:
|
|
default:
|
|
save_bufp->flags &= ~BUF_PIN;
|
|
return (ABNORMAL);
|
|
}
|
|
|
|
found:
|
|
switch (action) {
|
|
case HASH_PUTNEW:
|
|
save_bufp->flags &= ~BUF_PIN;
|
|
return (ABNORMAL);
|
|
case HASH_GET:
|
|
bp = (u_int16_t *)rbufp->page;
|
|
if (bp[ndx + 1] < REAL_KEY) {
|
|
if (__big_return(hashp, rbufp, ndx, val, 0))
|
|
return (ERROR);
|
|
} else {
|
|
val->data = (u_char *)rbufp->page + (int)bp[ndx + 1];
|
|
val->size = bp[ndx] - bp[ndx + 1];
|
|
}
|
|
break;
|
|
case HASH_PUT:
|
|
if ((__delpair(hashp, rbufp, ndx)) ||
|
|
(__addel(hashp, rbufp, key, val))) {
|
|
save_bufp->flags &= ~BUF_PIN;
|
|
return (ERROR);
|
|
}
|
|
break;
|
|
case HASH_DELETE:
|
|
if (__delpair(hashp, rbufp, ndx))
|
|
return (ERROR);
|
|
break;
|
|
default:
|
|
abort();
|
|
}
|
|
save_bufp->flags &= ~BUF_PIN;
|
|
return (SUCCESS);
|
|
}
|
|
|
|
static int
|
|
hash_seq(dbp, key, data, flag)
|
|
const DB *dbp;
|
|
DBT *key, *data;
|
|
u_int32_t flag;
|
|
{
|
|
register u_int32_t bucket;
|
|
register BUFHEAD *bufp;
|
|
HTAB *hashp;
|
|
u_int16_t *bp, ndx;
|
|
|
|
hashp = (HTAB *)dbp->internal;
|
|
if (flag && flag != R_FIRST && flag != R_NEXT) {
|
|
hashp->errnum = errno = EINVAL;
|
|
return (ERROR);
|
|
}
|
|
#ifdef HASH_STATISTICS
|
|
hash_accesses++;
|
|
#endif
|
|
if ((hashp->cbucket < 0) || (flag == R_FIRST)) {
|
|
hashp->cbucket = 0;
|
|
hashp->cndx = 1;
|
|
hashp->cpage = NULL;
|
|
}
|
|
|
|
for (bp = NULL; !bp || !bp[0]; ) {
|
|
if (!(bufp = hashp->cpage)) {
|
|
for (bucket = hashp->cbucket;
|
|
bucket <= (u_int32_t) hashp->MAX_BUCKET;
|
|
bucket++, hashp->cndx = 1) {
|
|
bufp = __get_buf(hashp, bucket, NULL, 0);
|
|
if (!bufp)
|
|
return (ERROR);
|
|
hashp->cpage = bufp;
|
|
bp = (u_int16_t *)bufp->page;
|
|
if (bp[0])
|
|
break;
|
|
}
|
|
hashp->cbucket = bucket;
|
|
if (hashp->cbucket > hashp->MAX_BUCKET) {
|
|
hashp->cbucket = -1;
|
|
return (ABNORMAL);
|
|
}
|
|
} else
|
|
bp = (u_int16_t *)hashp->cpage->page;
|
|
|
|
#ifdef DEBUG
|
|
assert(bp);
|
|
assert(bufp);
|
|
#endif
|
|
while (bp[hashp->cndx + 1] == OVFLPAGE) {
|
|
bufp = hashp->cpage =
|
|
__get_buf(hashp, bp[hashp->cndx], bufp, 0);
|
|
if (!bufp)
|
|
return (ERROR);
|
|
bp = (u_int16_t *)(bufp->page);
|
|
hashp->cndx = 1;
|
|
}
|
|
if (!bp[0]) {
|
|
hashp->cpage = NULL;
|
|
++hashp->cbucket;
|
|
}
|
|
}
|
|
ndx = hashp->cndx;
|
|
if (bp[ndx + 1] < REAL_KEY) {
|
|
if (__big_keydata(hashp, bufp, key, data, 1))
|
|
return (ERROR);
|
|
} else {
|
|
key->data = (u_char *)hashp->cpage->page + bp[ndx];
|
|
key->size = (ndx > 1 ? bp[ndx - 1] : hashp->BSIZE) - bp[ndx];
|
|
data->data = (u_char *)hashp->cpage->page + bp[ndx + 1];
|
|
data->size = bp[ndx] - bp[ndx + 1];
|
|
ndx += 2;
|
|
if (ndx > bp[0]) {
|
|
hashp->cpage = NULL;
|
|
hashp->cbucket++;
|
|
hashp->cndx = 1;
|
|
} else
|
|
hashp->cndx = ndx;
|
|
}
|
|
return (SUCCESS);
|
|
}
|
|
|
|
/********************************* UTILITIES ************************/
|
|
|
|
/*
|
|
* Returns:
|
|
* 0 ==> OK
|
|
* -1 ==> Error
|
|
*/
|
|
extern int
|
|
__expand_table(hashp)
|
|
HTAB *hashp;
|
|
{
|
|
u_int32_t old_bucket, new_bucket;
|
|
int dirsize, new_segnum, spare_ndx;
|
|
|
|
#ifdef HASH_STATISTICS
|
|
hash_expansions++;
|
|
#endif
|
|
new_bucket = ++hashp->MAX_BUCKET;
|
|
old_bucket = (hashp->MAX_BUCKET & hashp->LOW_MASK);
|
|
|
|
new_segnum = new_bucket >> hashp->SSHIFT;
|
|
|
|
/* Check if we need a new segment */
|
|
if (new_segnum >= hashp->nsegs) {
|
|
/* Check if we need to expand directory */
|
|
if (new_segnum >= hashp->DSIZE) {
|
|
/* Reallocate directory */
|
|
dirsize = hashp->DSIZE * sizeof(SEGMENT *);
|
|
if (!hash_realloc(&hashp->dir, dirsize, dirsize << 1))
|
|
return (-1);
|
|
hashp->DSIZE = dirsize << 1;
|
|
}
|
|
if ((hashp->dir[new_segnum] =
|
|
(SEGMENT)calloc(hashp->SGSIZE, sizeof(SEGMENT))) == NULL)
|
|
return (-1);
|
|
hashp->exsegs++;
|
|
hashp->nsegs++;
|
|
}
|
|
/*
|
|
* If the split point is increasing (MAX_BUCKET's log base 2
|
|
* * increases), we need to copy the current contents of the spare
|
|
* split bucket to the next bucket.
|
|
*/
|
|
spare_ndx = __hash_log2(hashp->MAX_BUCKET + 1);
|
|
if (spare_ndx > hashp->OVFL_POINT) {
|
|
hashp->SPARES[spare_ndx] = hashp->SPARES[hashp->OVFL_POINT];
|
|
hashp->OVFL_POINT = spare_ndx;
|
|
}
|
|
|
|
if (new_bucket > (u_int32_t) hashp->HIGH_MASK) {
|
|
/* Starting a new doubling */
|
|
hashp->LOW_MASK = hashp->HIGH_MASK;
|
|
hashp->HIGH_MASK = new_bucket | hashp->LOW_MASK;
|
|
}
|
|
/* Relocate records to the new bucket */
|
|
return (__split_page(hashp, old_bucket, new_bucket));
|
|
}
|
|
|
|
/*
|
|
* If realloc guarantees that the pointer is not destroyed if the realloc
|
|
* fails, then this routine can go away.
|
|
*/
|
|
static void *
|
|
hash_realloc(p_ptr, oldsize, newsize)
|
|
SEGMENT **p_ptr;
|
|
int oldsize, newsize;
|
|
{
|
|
register void *p;
|
|
|
|
if ((p = malloc(newsize))) {
|
|
memmove(p, *p_ptr, oldsize);
|
|
memset((char *)p + oldsize, 0, newsize - oldsize);
|
|
free(*p_ptr);
|
|
*p_ptr = p;
|
|
}
|
|
return (p);
|
|
}
|
|
|
|
extern u_int32_t
|
|
__call_hash(hashp, k, len)
|
|
HTAB *hashp;
|
|
char *k;
|
|
int len;
|
|
{
|
|
int n, bucket;
|
|
|
|
n = hashp->hash(k, len);
|
|
bucket = n & hashp->HIGH_MASK;
|
|
if (bucket > hashp->MAX_BUCKET)
|
|
bucket = bucket & hashp->LOW_MASK;
|
|
return (bucket);
|
|
}
|
|
|
|
/*
|
|
* Allocate segment table. On error, destroy the table and set errno.
|
|
*
|
|
* Returns 0 on success
|
|
*/
|
|
static int
|
|
alloc_segs(hashp, nsegs)
|
|
HTAB *hashp;
|
|
int nsegs;
|
|
{
|
|
register int i;
|
|
register SEGMENT store;
|
|
|
|
int save_errno;
|
|
|
|
if ((hashp->dir =
|
|
(SEGMENT *)calloc(hashp->DSIZE, sizeof(SEGMENT *))) == NULL) {
|
|
save_errno = errno;
|
|
(void)hdestroy(hashp);
|
|
errno = save_errno;
|
|
return (-1);
|
|
}
|
|
/* Allocate segments */
|
|
if ((store =
|
|
(SEGMENT)calloc(nsegs << hashp->SSHIFT, sizeof(SEGMENT))) == NULL) {
|
|
save_errno = errno;
|
|
(void)hdestroy(hashp);
|
|
errno = save_errno;
|
|
return (-1);
|
|
}
|
|
for (i = 0; i < nsegs; i++, hashp->nsegs++)
|
|
hashp->dir[i] = &store[i << hashp->SSHIFT];
|
|
return (0);
|
|
}
|
|
|
|
#if BYTE_ORDER == LITTLE_ENDIAN
|
|
/*
|
|
* Hashp->hdr needs to be byteswapped.
|
|
*/
|
|
static void
|
|
swap_header_copy(srcp, destp)
|
|
HASHHDR *srcp, *destp;
|
|
{
|
|
int i;
|
|
|
|
P_32_COPY(srcp->magic, destp->magic);
|
|
P_32_COPY(srcp->version, destp->version);
|
|
P_32_COPY(srcp->lorder, destp->lorder);
|
|
P_32_COPY(srcp->bsize, destp->bsize);
|
|
P_32_COPY(srcp->bshift, destp->bshift);
|
|
P_32_COPY(srcp->dsize, destp->dsize);
|
|
P_32_COPY(srcp->ssize, destp->ssize);
|
|
P_32_COPY(srcp->sshift, destp->sshift);
|
|
P_32_COPY(srcp->ovfl_point, destp->ovfl_point);
|
|
P_32_COPY(srcp->last_freed, destp->last_freed);
|
|
P_32_COPY(srcp->max_bucket, destp->max_bucket);
|
|
P_32_COPY(srcp->high_mask, destp->high_mask);
|
|
P_32_COPY(srcp->low_mask, destp->low_mask);
|
|
P_32_COPY(srcp->ffactor, destp->ffactor);
|
|
P_32_COPY(srcp->nkeys, destp->nkeys);
|
|
P_32_COPY(srcp->hdrpages, destp->hdrpages);
|
|
P_32_COPY(srcp->h_charkey, destp->h_charkey);
|
|
for (i = 0; i < NCACHED; i++) {
|
|
P_32_COPY(srcp->spares[i], destp->spares[i]);
|
|
P_16_COPY(srcp->bitmaps[i], destp->bitmaps[i]);
|
|
}
|
|
}
|
|
|
|
static void
|
|
swap_header(hashp)
|
|
HTAB *hashp;
|
|
{
|
|
HASHHDR *hdrp;
|
|
int i;
|
|
|
|
hdrp = &hashp->hdr;
|
|
|
|
M_32_SWAP(hdrp->magic);
|
|
M_32_SWAP(hdrp->version);
|
|
M_32_SWAP(hdrp->lorder);
|
|
M_32_SWAP(hdrp->bsize);
|
|
M_32_SWAP(hdrp->bshift);
|
|
M_32_SWAP(hdrp->dsize);
|
|
M_32_SWAP(hdrp->ssize);
|
|
M_32_SWAP(hdrp->sshift);
|
|
M_32_SWAP(hdrp->ovfl_point);
|
|
M_32_SWAP(hdrp->last_freed);
|
|
M_32_SWAP(hdrp->max_bucket);
|
|
M_32_SWAP(hdrp->high_mask);
|
|
M_32_SWAP(hdrp->low_mask);
|
|
M_32_SWAP(hdrp->ffactor);
|
|
M_32_SWAP(hdrp->nkeys);
|
|
M_32_SWAP(hdrp->hdrpages);
|
|
M_32_SWAP(hdrp->h_charkey);
|
|
for (i = 0; i < NCACHED; i++) {
|
|
M_32_SWAP(hdrp->spares[i]);
|
|
M_16_SWAP(hdrp->bitmaps[i]);
|
|
}
|
|
}
|
|
#endif
|