Ruby 2.7.6p219 (2022-04-12 revision c9c2245c0a25176072e02db9254f0e0c84c805cd)
sdbm.h
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1/*
2 * sdbm - ndbm work-alike hashed database library
3 * based on Per-Ake Larson's Dynamic Hashing algorithms. BIT 18 (1978).
4 * author: oz@nexus.yorku.ca
5 * status: public domain.
6 */
7#ifndef _SDBM_H_
8#define _SDBM_H_
9
10#include <stdio.h>
11
12#define DBLKSIZ 4096
13#define PBLKSIZ 1024
14#define PAIRMAX 1008 /* arbitrary on PBLKSIZ-N */
15#define SPLTMAX 10 /* maximum allowed splits */
16 /* for a single insertion */
17#define DIRFEXT ".dir"
18#define PAGFEXT ".pag"
19
20typedef struct {
21 int dirf; /* directory file descriptor */
22 int pagf; /* page file descriptor */
23 int flags; /* status/error flags, see below */
24 int keyptr; /* current key for nextkey */
25 off_t maxbno; /* size of dirfile in bits */
26 long curbit; /* current bit number */
27 long hmask; /* current hash mask */
28 long blkptr; /* current block for nextkey */
29 long blkno; /* current page to read/write */
30 long pagbno; /* current page in pagbuf */
31 char pagbuf[PBLKSIZ]; /* page file block buffer */
32 long dirbno; /* current block in dirbuf */
33 char dirbuf[DBLKSIZ]; /* directory file block buffer */
34} DBM;
35
36#define DBM_RDONLY 0x1 /* data base open read-only */
37#define DBM_IOERR 0x2 /* data base I/O error */
38
39/*
40 * utility macros
41 */
42#define sdbm_rdonly(db) ((db)->flags & DBM_RDONLY)
43#define sdbm_error(db) ((db)->flags & DBM_IOERR)
44
45#define sdbm_clearerr(db) ((db)->flags &= ~DBM_IOERR) /* ouch */
46
47#define sdbm_dirfno(db) ((db)->dirf)
48#define sdbm_pagfno(db) ((db)->pagf)
49
50typedef struct {
51 char *dptr;
52 int dsize;
53} datum;
54
55extern datum nullitem;
56
57#if defined(__STDC__)
58#define proto(p) p
59#else
60#define proto(p) ()
61#endif
62
63/*
64 * flags to sdbm_store
65 */
66#define DBM_INSERT 0
67#define DBM_REPLACE 1
68
69/*
70 * ndbm interface
71 */
72extern DBM *sdbm_open proto((char *, int, int));
73extern void sdbm_close proto((DBM *));
75extern int sdbm_delete proto((DBM *, datum));
76extern int sdbm_store proto((DBM *, datum, datum, int));
77extern datum sdbm_firstkey proto((DBM *));
78extern datum sdbm_nextkey proto((DBM *));
79
80/*
81 * other
82 */
83extern DBM *sdbm_prep proto((char *, char *, int, int));
84extern long sdbm_hash proto((char *, int));
85
86#endif /* _SDBM_H_ */
DBM * sdbm_prep(char *dirname, char *pagname, int flags, int mode)
Definition: _sdbm.c:199
int sdbm_store(register DBM *db, datum key, datum val, int flags)
Definition: _sdbm.c:312
int sdbm_delete(register DBM *db, datum key)
Definition: _sdbm.c:288
void sdbm_close(register DBM *db)
Definition: _sdbm.c:264
datum sdbm_firstkey(register DBM *db)
Definition: _sdbm.c:467
DBM * sdbm_open(register char *file, register int flags, register int mode)
Definition: _sdbm.c:147
datum sdbm_nextkey(register DBM *db)
Definition: _sdbm.c:486
long sdbm_hash(register char *str, register int len)
Definition: _sdbm.c:925
datum sdbm_fetch(register DBM *db, datum key)
Definition: _sdbm.c:276
__off_t off_t
datum nullitem
Definition: _sdbm.c:144
#define proto(p)
Definition: sdbm.h:60
#define PBLKSIZ
Definition: sdbm.h:13
#define DBLKSIZ
Definition: sdbm.h:12
Definition: sdbm.h:20
int keyptr
Definition: sdbm.h:24
long pagbno
Definition: sdbm.h:30
long hmask
Definition: sdbm.h:27
long dirbno
Definition: sdbm.h:32
long blkno
Definition: sdbm.h:29
long curbit
Definition: sdbm.h:26
int flags
Definition: sdbm.h:23
off_t maxbno
Definition: sdbm.h:25
int dirf
Definition: sdbm.h:21
long blkptr
Definition: sdbm.h:28
int pagf
Definition: sdbm.h:22
Definition: sdbm.h:50
char * dptr
Definition: sdbm.h:51
int dsize
Definition: sdbm.h:52