xref: /openbsd/lib/libc/db/hash/ndbm.c (revision 3bef86f7)
1 /*	$OpenBSD: ndbm.c,v 1.28 2023/02/17 17:59:36 miod Exp $	*/
2 
3 /*-
4  * Copyright (c) 1990, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * This code is derived from software contributed to Berkeley by
8  * Margo Seltzer.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. Neither the name of the University nor the names of its contributors
19  *    may be used to endorse or promote products derived from this software
20  *    without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  */
34 
35 #include <errno.h>
36 #include <fcntl.h>
37 #include <limits.h>
38 #include <stdio.h>
39 #include <string.h>
40 
41 #include <ndbm.h>
42 #include "hash.h"
43 
44 /*
45  *
46  * This package provides dbm and ndbm compatible interfaces to DB.
47  * First are the DBM routines, which call the NDBM routines, and
48  * the NDBM routines, which call the DB routines.
49  */
50 
51 static DBM *_dbm_open(const char *, const char *, int, mode_t);
52 
53 /*
54  * Returns:
55  * 	*DBM on success
56  *	 NULL on failure
57  */
58 static DBM *
59 _dbm_open(const char *file, const char *suff, int flags, mode_t mode)
60 {
61 	HASHINFO info;
62 	char path[PATH_MAX];
63 	int len;
64 
65 	len = snprintf(path, sizeof path, "%s%s", file, suff);
66 	if (len < 0 || len >= sizeof path) {
67 		errno = ENAMETOOLONG;
68 		return (NULL);
69 	}
70 	/* O_WRONLY not supported by db(3) but traditional ndbm allowed it. */
71 	if ((flags & O_ACCMODE) == O_WRONLY) {
72 		flags &= ~O_WRONLY;
73 		flags |= O_RDWR;
74 	}
75 	info.bsize = 4096;
76 	info.ffactor = 40;
77 	info.nelem = 1;
78 	info.cachesize = 0;
79 	info.hash = NULL;
80 	info.lorder = 0;
81 	return ((DBM *)__hash_open(path, flags, mode, &info, 0));
82 }
83 
84 /*
85  * Returns:
86  * 	*DBM on success
87  *	 NULL on failure
88  */
89 DBM *
90 dbm_open(const char *file, int flags, mode_t mode)
91 {
92 
93 	return(_dbm_open(file, DBM_SUFFIX, flags, mode));
94 }
95 
96 /*
97  * Returns:
98  *	Nothing.
99  */
100 void
101 dbm_close(DBM *db)
102 {
103 
104 	(void)(db->close)(db);
105 }
106 DEF_WEAK(dbm_close);
107 
108 /*
109  * Returns:
110  *	DATUM on success
111  *	NULL on failure
112  */
113 datum
114 dbm_fetch(DBM *db, datum key)
115 {
116 	datum retdata;
117 	int status;
118 	DBT dbtkey, dbtretdata;
119 
120 	dbtkey.data = key.dptr;
121 	dbtkey.size = key.dsize;
122 	status = (db->get)(db, &dbtkey, &dbtretdata, 0);
123 	if (status) {
124 		dbtretdata.data = NULL;
125 		dbtretdata.size = 0;
126 	}
127 	retdata.dptr = dbtretdata.data;
128 	retdata.dsize = dbtretdata.size;
129 	return (retdata);
130 }
131 DEF_WEAK(dbm_fetch);
132 
133 /*
134  * Returns:
135  *	DATUM on success
136  *	NULL on failure
137  */
138 datum
139 dbm_firstkey(DBM *db)
140 {
141 	int status;
142 	datum retkey;
143 	DBT dbtretkey, dbtretdata;
144 
145 	status = (db->seq)(db, &dbtretkey, &dbtretdata, R_FIRST);
146 	if (status)
147 		dbtretkey.data = NULL;
148 	retkey.dptr = dbtretkey.data;
149 	retkey.dsize = dbtretkey.size;
150 	return (retkey);
151 }
152 DEF_WEAK(dbm_firstkey);
153 
154 /*
155  * Returns:
156  *	DATUM on success
157  *	NULL on failure
158  */
159 datum
160 dbm_nextkey(DBM *db)
161 {
162 	int status;
163 	datum retkey;
164 	DBT dbtretkey, dbtretdata;
165 
166 	status = (db->seq)(db, &dbtretkey, &dbtretdata, R_NEXT);
167 	if (status)
168 		dbtretkey.data = NULL;
169 	retkey.dptr = dbtretkey.data;
170 	retkey.dsize = dbtretkey.size;
171 	return (retkey);
172 }
173 DEF_WEAK(dbm_nextkey);
174 
175 /*
176  * Returns:
177  *	 0 on success
178  *	<0 on failure
179  */
180 int
181 dbm_delete(DBM *db, datum key)
182 {
183 	int status;
184 	DBT dbtkey;
185 
186 	dbtkey.data = key.dptr;
187 	dbtkey.size = key.dsize;
188 	status = (db->del)(db, &dbtkey, 0);
189 	if (status)
190 		return (-1);
191 	else
192 		return (0);
193 }
194 DEF_WEAK(dbm_delete);
195 
196 /*
197  * Returns:
198  *	 0 on success
199  *	<0 on failure
200  *	 1 if DBM_INSERT and entry exists
201  */
202 int
203 dbm_store(DBM *db, datum key, datum data, int flags)
204 {
205 	DBT dbtkey, dbtdata;
206 
207 	dbtkey.data = key.dptr;
208 	dbtkey.size = key.dsize;
209 	dbtdata.data = data.dptr;
210 	dbtdata.size = data.dsize;
211 	return ((db->put)(db, &dbtkey, &dbtdata,
212 	    (flags == DBM_INSERT) ? R_NOOVERWRITE : 0));
213 }
214 DEF_WEAK(dbm_store);
215 
216 int
217 dbm_error(DBM *db)
218 {
219 	HTAB *hp;
220 
221 	hp = (HTAB *)db->internal;
222 	return (hp->err);
223 }
224 
225 int
226 dbm_clearerr(DBM *db)
227 {
228 	HTAB *hp;
229 
230 	hp = (HTAB *)db->internal;
231 	hp->err = 0;
232 	return (0);
233 }
234 
235 int
236 dbm_dirfno(DBM *db)
237 {
238 
239 	return(((HTAB *)db->internal)->fp);
240 }
241 
242 int
243 dbm_rdonly(DBM *dbp)
244 {
245 	HTAB *hashp = (HTAB *)dbp->internal;
246 
247 	/* Could use DBM_RDONLY instead if we wanted... */
248 	return ((hashp->flags & O_ACCMODE) == O_RDONLY);
249 }
250 DEF_WEAK(dbm_rdonly);
251