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 #include <sys/types.h>
33
34 #include <errno.h>
35 #include <stddef.h>
36 #include <stdio.h>
37 #include <stdlib.h>
38 #include <string.h>
39 #include <unistd.h>
40
41 #include <db.h>
42 #include "recno.h"
43
44 /*
45 * __REC_GET -- Get a record from the btree.
46 *
47 * Parameters:
48 * dbp: pointer to access method
49 * key: key to find
50 * data: data to return
51 * flag: currently unused
52 *
53 * Returns:
54 * RET_ERROR, RET_SUCCESS and RET_SPECIAL if the key not found.
55 */
56 int
__rec_get(const DB * dbp,const DBT * key,DBT * data,u_int flags)57 __rec_get(const DB *dbp, const DBT *key, DBT *data, u_int flags)
58 {
59 BTREE *t;
60 EPG *e;
61 recno_t nrec;
62 int status;
63
64 t = dbp->internal;
65
66 /* Toss any page pinned across calls. */
67 if (t->bt_pinned != NULL) {
68 mpool_put(t->bt_mp, t->bt_pinned, 0);
69 t->bt_pinned = NULL;
70 }
71
72 /* Get currently doesn't take any flags, and keys of 0 are illegal. */
73 if (flags || (nrec = *(recno_t *)key->data) == 0) {
74 errno = EINVAL;
75 return (RET_ERROR);
76 }
77
78 /*
79 * If we haven't seen this record yet, try to find it in the
80 * original file.
81 */
82 if (nrec > t->bt_nrecs) {
83 if (F_ISSET(t, R_EOF | R_INMEM))
84 return (RET_SPECIAL);
85 if ((status = t->bt_irec(t, nrec)) != RET_SUCCESS)
86 return (status);
87 }
88
89 --nrec;
90 if ((e = __rec_search(t, nrec, SEARCH)) == NULL)
91 return (RET_ERROR);
92
93 status = __rec_ret(t, e, 0, NULL, data);
94 if (F_ISSET(t, B_DB_LOCK))
95 mpool_put(t->bt_mp, e->page, 0);
96 else
97 t->bt_pinned = e->page;
98 return (status);
99 }
100
101 /*
102 * __REC_FPIPE -- Get fixed length records from a pipe.
103 *
104 * Parameters:
105 * t: tree
106 * cnt: records to read
107 *
108 * Returns:
109 * RET_ERROR, RET_SUCCESS
110 */
111 int
__rec_fpipe(BTREE * t,recno_t top)112 __rec_fpipe(BTREE *t, recno_t top)
113 {
114 DBT data;
115 recno_t nrec;
116 size_t len;
117 int ch;
118 u_char *p;
119
120 if (t->bt_rdata.size < t->bt_reclen) {
121 t->bt_rdata.data = reallocf(t->bt_rdata.data, t->bt_reclen);
122 if (t->bt_rdata.data == NULL)
123 return (RET_ERROR);
124 t->bt_rdata.size = t->bt_reclen;
125 }
126 data.data = t->bt_rdata.data;
127 data.size = t->bt_reclen;
128
129 for (nrec = t->bt_nrecs; nrec < top;) {
130 len = t->bt_reclen;
131 for (p = t->bt_rdata.data;; *p++ = ch)
132 if ((ch = getc(t->bt_rfp)) == EOF || !--len) {
133 if (ch != EOF)
134 *p = ch;
135 if (len != 0)
136 memset(p, t->bt_bval, len);
137 if (__rec_iput(t,
138 nrec, &data, 0) != RET_SUCCESS)
139 return (RET_ERROR);
140 ++nrec;
141 break;
142 }
143 if (ch == EOF)
144 break;
145 }
146 if (nrec < top) {
147 F_SET(t, R_EOF);
148 return (RET_SPECIAL);
149 }
150 return (RET_SUCCESS);
151 }
152
153 /*
154 * __REC_VPIPE -- Get variable length records from a pipe.
155 *
156 * Parameters:
157 * t: tree
158 * cnt: records to read
159 *
160 * Returns:
161 * RET_ERROR, RET_SUCCESS
162 */
163 int
__rec_vpipe(BTREE * t,recno_t top)164 __rec_vpipe(BTREE *t, recno_t top)
165 {
166 DBT data;
167 recno_t nrec;
168 size_t len;
169 size_t sz;
170 int bval, ch;
171 u_char *p;
172
173 bval = t->bt_bval;
174 for (nrec = t->bt_nrecs; nrec < top; ++nrec) {
175 for (p = t->bt_rdata.data,
176 sz = t->bt_rdata.size;; *p++ = ch, --sz) {
177 if ((ch = getc(t->bt_rfp)) == EOF || ch == bval) {
178 data.data = t->bt_rdata.data;
179 data.size = p - (u_char *)t->bt_rdata.data;
180 if (ch == EOF && data.size == 0)
181 break;
182 if (__rec_iput(t, nrec, &data, 0)
183 != RET_SUCCESS)
184 return (RET_ERROR);
185 break;
186 }
187 if (sz == 0) {
188 len = p - (u_char *)t->bt_rdata.data;
189 t->bt_rdata.size += (sz = 256);
190 t->bt_rdata.data = reallocf(t->bt_rdata.data, t->bt_rdata.size);
191 if (t->bt_rdata.data == NULL)
192 return (RET_ERROR);
193 p = (u_char *)t->bt_rdata.data + len;
194 }
195 }
196 if (ch == EOF)
197 break;
198 }
199 if (nrec < top) {
200 F_SET(t, R_EOF);
201 return (RET_SPECIAL);
202 }
203 return (RET_SUCCESS);
204 }
205
206 /*
207 * __REC_FMAP -- Get fixed length records from a file.
208 *
209 * Parameters:
210 * t: tree
211 * cnt: records to read
212 *
213 * Returns:
214 * RET_ERROR, RET_SUCCESS
215 */
216 int
__rec_fmap(BTREE * t,recno_t top)217 __rec_fmap(BTREE *t, recno_t top)
218 {
219 DBT data;
220 recno_t nrec;
221 u_char *sp, *ep, *p;
222 size_t len;
223
224 if (t->bt_rdata.size < t->bt_reclen) {
225 t->bt_rdata.data = reallocf(t->bt_rdata.data, t->bt_reclen);
226 if (t->bt_rdata.data == NULL)
227 return (RET_ERROR);
228 t->bt_rdata.size = t->bt_reclen;
229 }
230 data.data = t->bt_rdata.data;
231 data.size = t->bt_reclen;
232
233 sp = (u_char *)t->bt_cmap;
234 ep = (u_char *)t->bt_emap;
235 for (nrec = t->bt_nrecs; nrec < top; ++nrec) {
236 if (sp >= ep) {
237 F_SET(t, R_EOF);
238 return (RET_SPECIAL);
239 }
240 len = t->bt_reclen;
241 for (p = t->bt_rdata.data;
242 sp < ep && len > 0; *p++ = *sp++, --len);
243 if (len != 0)
244 memset(p, t->bt_bval, len);
245 if (__rec_iput(t, nrec, &data, 0) != RET_SUCCESS)
246 return (RET_ERROR);
247 }
248 t->bt_cmap = (caddr_t)sp;
249 return (RET_SUCCESS);
250 }
251
252 /*
253 * __REC_VMAP -- Get variable length records from a file.
254 *
255 * Parameters:
256 * t: tree
257 * cnt: records to read
258 *
259 * Returns:
260 * RET_ERROR, RET_SUCCESS
261 */
262 int
__rec_vmap(BTREE * t,recno_t top)263 __rec_vmap(BTREE *t, recno_t top)
264 {
265 DBT data;
266 u_char *sp, *ep;
267 recno_t nrec;
268 int bval;
269
270 sp = (u_char *)t->bt_cmap;
271 ep = (u_char *)t->bt_emap;
272 bval = t->bt_bval;
273
274 for (nrec = t->bt_nrecs; nrec < top; ++nrec) {
275 if (sp >= ep) {
276 F_SET(t, R_EOF);
277 return (RET_SPECIAL);
278 }
279 for (data.data = sp; sp < ep && *sp != bval; ++sp);
280 data.size = sp - (u_char *)data.data;
281 if (__rec_iput(t, nrec, &data, 0) != RET_SUCCESS)
282 return (RET_ERROR);
283 ++sp;
284 }
285 t->bt_cmap = (caddr_t)sp;
286 return (RET_SUCCESS);
287 }
288