dbm/sdbm/sdbm_private.h

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/*
 * sdbm - ndbm work-alike hashed database library
 * based on Per-Ake Larson's Dynamic Hashing algorithms. BIT 18 (1978).
 * author: oz@nexus.yorku.ca
 */

#ifndef SDBM_PRIVATE_H
#define SDBM_PRIVATE_H

#include "apr.h"
#include "apr_pools.h"
#include "apr_file_io.h"
#include "apr_errno.h" /* for apr_status_t */

/* increase the block/page size and what can be inserted */

#if 1
#define DBLKSIZ 16384
#define PBLKSIZ 8192
#define PAIRMAX 8008			/* arbitrary on PBLKSIZ-N */
#else
#define DBLKSIZ 4096
#define PBLKSIZ 1024
#define PAIRMAX 1008			/* arbitrary on PBLKSIZ-N */
#endif
#define SPLTMAX	10			/* maximum allowed splits */

/* for SDBM.flags */
#define SDBM_RDONLY	0x1	       /* data base open read-only */
					/* for a single insertion */
struct SDBM {
    apr_pool_t *pool;
    apr_file_t *dirf;		       /* directory file descriptor */
    apr_file_t *pagf;		       /* page file descriptor */
    apr_int32_t flags;		       /* status/error flags, see below */
    long maxbno;		       /* size of dirfile in bits */
    long curbit;		       /* current bit number */
    long hmask;			       /* current hash mask */
    long blkptr;		       /* current block for nextkey */
    int keyptr;			       /* current key for nextkey */
    long blkno;			       /* current page to read/write */
    long pagbno;		       /* current page in pagbuf */
    char pagbuf[PBLKSIZ];	       /* page file block buffer */
    long dirbno;		       /* current block in dirbuf */
    char dirbuf[DBLKSIZ];	       /* directory file block buffer */
};

apr_status_t sdbm_lock(SDBM *db);
apr_status_t sdbm_unlock(SDBM *db);

extern const sdbm_datum sdbm_nullitem;

#endif /* SDBM_PRIVATE_H */