sdbm_private.h revision 259065 
113065Skvn/* Licensed to the Apache Software Foundation (ASF) under one or more
213065Skvn * contributor license agreements.  See the NOTICE file distributed with
313065Skvn * this work for additional information regarding copyright ownership.
413065Skvn * The ASF licenses this file to You under the Apache License, Version 2.0
513065Skvn * (the "License"); you may not use this file except in compliance with
613065Skvn * the License.  You may obtain a copy of the License at
713065Skvn *
813065Skvn *     http://www.apache.org/licenses/LICENSE-2.0
913065Skvn *
1013065Skvn * Unless required by applicable law or agreed to in writing, software
1113065Skvn * distributed under the License is distributed on an "AS IS" BASIS,
1213065Skvn * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
1313065Skvn * See the License for the specific language governing permissions and
1413065Skvn * limitations under the License.
1513065Skvn */
1613065Skvn
1713065Skvn/*
1813065Skvn * sdbm - ndbm work-alike hashed database library
1913065Skvn * based on Per-Ake Larson's Dynamic Hashing algorithms. BIT 18 (1978).
2013065Skvn * author: oz@nexus.yorku.ca
2113065Skvn */
2213065Skvn
2313065Skvn#ifndef SDBM_PRIVATE_H
2413065Skvn#define SDBM_PRIVATE_H
2513065Skvn
2613065Skvn#include "apr.h"
2713065Skvn#include "apr_pools.h"
2813065Skvn#include "apr_file_io.h"
2913065Skvn#include "apr_errno.h" /* for apr_status_t */
3013065Skvn
3113065Skvn#if 0
3213065Skvn/* if the block/page size is increased, it breaks perl apr_sdbm_t compatibility */
3313065Skvn#define DBLKSIZ 16384
3413065Skvn#define PBLKSIZ 8192
3513065Skvn#define PAIRMAX 8008			/* arbitrary on PBLKSIZ-N */
3613065Skvn#else
3713065Skvn#define DBLKSIZ 4096
3813065Skvn#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