1/* Licensed to the Apache Software Foundation (ASF) under one or more
2 * contributor license agreements.  See the NOTICE file distributed with
3 * this work for additional information regarding copyright ownership.
4 * The ASF licenses this file to You under the Apache License, Version 2.0
5 * (the "License"); you may not use this file except in compliance with
6 * the License.  You may obtain a copy of the License at
7 *
8 *     http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17/*
18 * sdbm - ndbm work-alike hashed database library
19 * based on Per-Ake Larson's Dynamic Hashing algorithms. BIT 18 (1978).
20 * author: oz@nexus.yorku.ca
21 */
22
23#ifndef SDBM_PRIVATE_H
24#define SDBM_PRIVATE_H
25
26#include "apr.h"
27#include "apr_pools.h"
28#include "apr_file_io.h"
29#include "apr_errno.h" /* for apr_status_t */
30
31#if 0
32/* if the block/page size is increased, it breaks perl apr_sdbm_t compatibility */
33#define DBLKSIZ 16384
34#define PBLKSIZ 8192
35#define PAIRMAX 8008			/* arbitrary on PBLKSIZ-N */
36#else
37#define DBLKSIZ 4096
38#define PBLKSIZ 1024
39#define PAIRMAX 1008			/* arbitrary on PBLKSIZ-N */
40#endif
41#define SPLTMAX	10			/* maximum allowed splits */
42
43/* for apr_sdbm_t.flags */
44#define SDBM_RDONLY	        0x1    /* data base open read-only */
45#define SDBM_SHARED	        0x2    /* data base open for sharing */
46#define SDBM_SHARED_LOCK	0x4    /* data base locked for shared read */
47#define SDBM_EXCLUSIVE_LOCK	0x8    /* data base locked for write */
48
49struct apr_sdbm_t {
50    apr_pool_t *pool;
51    apr_file_t *dirf;		       /* directory file descriptor */
52    apr_file_t *pagf;		       /* page file descriptor */
53    apr_int32_t flags;		       /* status/error flags, see below */
54    long maxbno;		       /* size of dirfile in bits */
55    long curbit;		       /* current bit number */
56    long hmask;			       /* current hash mask */
57    long blkptr;		       /* current block for nextkey */
58    int  keyptr;		       /* current key for nextkey */
59    long blkno;			       /* current page to read/write */
60    long pagbno;		       /* current page in pagbuf */
61    char pagbuf[PBLKSIZ];	       /* page file block buffer */
62    long dirbno;		       /* current block in dirbuf */
63    char dirbuf[DBLKSIZ];	       /* directory file block buffer */
64    int  lckcnt;                       /* number of calls to sdbm_lock */
65};
66
67
68#define sdbm_hash apu__sdbm_hash
69#define sdbm_nullitem apu__sdbm_nullitem
70
71extern const apr_sdbm_datum_t sdbm_nullitem;
72
73long sdbm_hash(const char *str, int len);
74
75/*
76 * zero the cache
77 */
78#define SDBM_INVALIDATE_CACHE(db, finfo) \
79    do { db->dirbno = (!finfo.size) ? 0 : -1; \
80         db->pagbno = -1; \
81         db->maxbno = (long)(finfo.size * BYTESIZ); \
82    } while (0);
83
84#endif /* SDBM_PRIVATE_H */
85