1 /*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 1990, 1993, 1994
5 * The Regents of the University of California. All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. Neither the name of the University nor the names of its contributors
16 * may be used to endorse or promote products derived from this software
17 * without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 */
31
32 #if defined(LIBC_SCCS) && !defined(lint)
33 static char sccsid[] = "@(#)rec_get.c 8.9 (Berkeley) 8/18/94";
34 #endif /* LIBC_SCCS and not lint */
35 #include <sys/cdefs.h>
36 __FBSDID("$FreeBSD: stable/12/lib/libc/db/recno/rec_get.c 326025 2017-11-20 19:49:47Z pfg $");
37
38 #include <sys/types.h>
39
40 #include <errno.h>
41 #include <stddef.h>
42 #include <stdio.h>
43 #include <stdlib.h>
44 #include <string.h>
45 #include <unistd.h>
46
47 #include <db.h>
48 #include "recno.h"
49
50 /*
51 * __REC_GET -- Get a record from the btree.
52 *
53 * Parameters:
54 * dbp: pointer to access method
55 * key: key to find
56 * data: data to return
57 * flag: currently unused
58 *
59 * Returns:
60 * RET_ERROR, RET_SUCCESS and RET_SPECIAL if the key not found.
61 */
62 int
__rec_get(const DB * dbp,const DBT * key,DBT * data,u_int flags)63 __rec_get(const DB *dbp, const DBT *key, DBT *data, u_int flags)
64 {
65 BTREE *t;
66 EPG *e;
67 recno_t nrec;
68 int status;
69
70 t = dbp->internal;
71
72 /* Toss any page pinned across calls. */
73 if (t->bt_pinned != NULL) {
74 mpool_put(t->bt_mp, t->bt_pinned, 0);
75 t->bt_pinned = NULL;
76 }
77
78 /* Get currently doesn't take any flags, and keys of 0 are illegal. */
79 if (flags || (nrec = *(recno_t *)key->data) == 0) {
80 errno = EINVAL;
81 return (RET_ERROR);
82 }
83
84 /*
85 * If we haven't seen this record yet, try to find it in the
86 * original file.
87 */
88 if (nrec > t->bt_nrecs) {
89 if (F_ISSET(t, R_EOF | R_INMEM))
90 return (RET_SPECIAL);
91 if ((status = t->bt_irec(t, nrec)) != RET_SUCCESS)
92 return (status);
93 }
94
95 --nrec;
96 if ((e = __rec_search(t, nrec, SEARCH)) == NULL)
97 return (RET_ERROR);
98
99 status = __rec_ret(t, e, 0, NULL, data);
100 if (F_ISSET(t, B_DB_LOCK))
101 mpool_put(t->bt_mp, e->page, 0);
102 else
103 t->bt_pinned = e->page;
104 return (status);
105 }
106
107 /*
108 * __REC_FPIPE -- Get fixed length records from a pipe.
109 *
110 * Parameters:
111 * t: tree
112 * cnt: records to read
113 *
114 * Returns:
115 * RET_ERROR, RET_SUCCESS
116 */
117 int
__rec_fpipe(BTREE * t,recno_t top)118 __rec_fpipe(BTREE *t, recno_t top)
119 {
120 DBT data;
121 recno_t nrec;
122 size_t len;
123 int ch;
124 u_char *p;
125
126 if (t->bt_rdata.size < t->bt_reclen) {
127 t->bt_rdata.data = reallocf(t->bt_rdata.data, t->bt_reclen);
128 if (t->bt_rdata.data == NULL)
129 return (RET_ERROR);
130 t->bt_rdata.size = t->bt_reclen;
131 }
132 data.data = t->bt_rdata.data;
133 data.size = t->bt_reclen;
134
135 for (nrec = t->bt_nrecs; nrec < top;) {
136 len = t->bt_reclen;
137 for (p = t->bt_rdata.data;; *p++ = ch)
138 if ((ch = getc(t->bt_rfp)) == EOF || !--len) {
139 if (ch != EOF)
140 *p = ch;
141 if (len != 0)
142 memset(p, t->bt_bval, len);
143 if (__rec_iput(t,
144 nrec, &data, 0) != RET_SUCCESS)
145 return (RET_ERROR);
146 ++nrec;
147 break;
148 }
149 if (ch == EOF)
150 break;
151 }
152 if (nrec < top) {
153 F_SET(t, R_EOF);
154 return (RET_SPECIAL);
155 }
156 return (RET_SUCCESS);
157 }
158
159 /*
160 * __REC_VPIPE -- Get variable length records from a pipe.
161 *
162 * Parameters:
163 * t: tree
164 * cnt: records to read
165 *
166 * Returns:
167 * RET_ERROR, RET_SUCCESS
168 */
169 int
__rec_vpipe(BTREE * t,recno_t top)170 __rec_vpipe(BTREE *t, recno_t top)
171 {
172 DBT data;
173 recno_t nrec;
174 size_t len;
175 size_t sz;
176 int bval, ch;
177 u_char *p;
178
179 bval = t->bt_bval;
180 for (nrec = t->bt_nrecs; nrec < top; ++nrec) {
181 for (p = t->bt_rdata.data,
182 sz = t->bt_rdata.size;; *p++ = ch, --sz) {
183 if ((ch = getc(t->bt_rfp)) == EOF || ch == bval) {
184 data.data = t->bt_rdata.data;
185 data.size = p - (u_char *)t->bt_rdata.data;
186 if (ch == EOF && data.size == 0)
187 break;
188 if (__rec_iput(t, nrec, &data, 0)
189 != RET_SUCCESS)
190 return (RET_ERROR);
191 break;
192 }
193 if (sz == 0) {
194 len = p - (u_char *)t->bt_rdata.data;
195 t->bt_rdata.size += (sz = 256);
196 t->bt_rdata.data = reallocf(t->bt_rdata.data, t->bt_rdata.size);
197 if (t->bt_rdata.data == NULL)
198 return (RET_ERROR);
199 p = (u_char *)t->bt_rdata.data + len;
200 }
201 }
202 if (ch == EOF)
203 break;
204 }
205 if (nrec < top) {
206 F_SET(t, R_EOF);
207 return (RET_SPECIAL);
208 }
209 return (RET_SUCCESS);
210 }
211
212 /*
213 * __REC_FMAP -- Get fixed length records from a file.
214 *
215 * Parameters:
216 * t: tree
217 * cnt: records to read
218 *
219 * Returns:
220 * RET_ERROR, RET_SUCCESS
221 */
222 int
__rec_fmap(BTREE * t,recno_t top)223 __rec_fmap(BTREE *t, recno_t top)
224 {
225 DBT data;
226 recno_t nrec;
227 u_char *sp, *ep, *p;
228 size_t len;
229
230 if (t->bt_rdata.size < t->bt_reclen) {
231 t->bt_rdata.data = reallocf(t->bt_rdata.data, t->bt_reclen);
232 if (t->bt_rdata.data == NULL)
233 return (RET_ERROR);
234 t->bt_rdata.size = t->bt_reclen;
235 }
236 data.data = t->bt_rdata.data;
237 data.size = t->bt_reclen;
238
239 sp = (u_char *)t->bt_cmap;
240 ep = (u_char *)t->bt_emap;
241 for (nrec = t->bt_nrecs; nrec < top; ++nrec) {
242 if (sp >= ep) {
243 F_SET(t, R_EOF);
244 return (RET_SPECIAL);
245 }
246 len = t->bt_reclen;
247 for (p = t->bt_rdata.data;
248 sp < ep && len > 0; *p++ = *sp++, --len);
249 if (len != 0)
250 memset(p, t->bt_bval, len);
251 if (__rec_iput(t, nrec, &data, 0) != RET_SUCCESS)
252 return (RET_ERROR);
253 }
254 t->bt_cmap = (caddr_t)sp;
255 return (RET_SUCCESS);
256 }
257
258 /*
259 * __REC_VMAP -- Get variable length records from a file.
260 *
261 * Parameters:
262 * t: tree
263 * cnt: records to read
264 *
265 * Returns:
266 * RET_ERROR, RET_SUCCESS
267 */
268 int
__rec_vmap(BTREE * t,recno_t top)269 __rec_vmap(BTREE *t, recno_t top)
270 {
271 DBT data;
272 u_char *sp, *ep;
273 recno_t nrec;
274 int bval;
275
276 sp = (u_char *)t->bt_cmap;
277 ep = (u_char *)t->bt_emap;
278 bval = t->bt_bval;
279
280 for (nrec = t->bt_nrecs; nrec < top; ++nrec) {
281 if (sp >= ep) {
282 F_SET(t, R_EOF);
283 return (RET_SPECIAL);
284 }
285 for (data.data = sp; sp < ep && *sp != bval; ++sp);
286 data.size = sp - (u_char *)data.data;
287 if (__rec_iput(t, nrec, &data, 0) != RET_SUCCESS)
288 return (RET_ERROR);
289 ++sp;
290 }
291 t->bt_cmap = (caddr_t)sp;
292 return (RET_SUCCESS);
293 }
294