1 /*-
2 * Copyright (c) 1990, 1993, 1994
3 * The Regents of the University of California. All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. All advertising materials mentioning features or use of this software
14 * must display the following acknowledgement:
15 * This product includes software developed by the University of
16 * California, Berkeley and its contributors.
17 * 4. Neither the name of the University nor the names of its contributors
18 * may be used to endorse or promote products derived from this software
19 * without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 */
33
34 #if defined(LIBC_SCCS) && !defined(lint)
35 static char sccsid[] = "@(#)rec_get.c 8.9 (Berkeley) 8/18/94";
36 #endif /* LIBC_SCCS and not lint */
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-int.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(dbp,key,data,flags)63 __rec_get(dbp, key, data, flags)
64 const DB *dbp;
65 const DBT *key;
66 DBT *data;
67 u_int flags;
68 {
69 BTREE *t;
70 EPG *e;
71 recno_t nrec;
72 int status;
73
74 t = dbp->internal;
75
76 /* Toss any page pinned across calls. */
77 if (t->bt_pinned != NULL) {
78 mpool_put(t->bt_mp, t->bt_pinned, 0);
79 t->bt_pinned = NULL;
80 }
81
82 /* Get currently doesn't take any flags, and keys of 0 are illegal. */
83 if (flags || (nrec = *(recno_t *)key->data) == 0) {
84 errno = EINVAL;
85 return (RET_ERROR);
86 }
87
88 /*
89 * If we haven't seen this record yet, try to find it in the
90 * original file.
91 */
92 if (nrec > t->bt_nrecs) {
93 if (F_ISSET(t, R_EOF | R_INMEM))
94 return (RET_SPECIAL);
95 if ((status = t->bt_irec(t, nrec)) != RET_SUCCESS)
96 return (status);
97 }
98
99 --nrec;
100 if ((e = __rec_search(t, nrec, SEARCH)) == NULL)
101 return (RET_ERROR);
102
103 status = __rec_ret(t, e, 0, NULL, data);
104 if (F_ISSET(t, B_DB_LOCK))
105 mpool_put(t->bt_mp, e->page, 0);
106 else
107 t->bt_pinned = e->page;
108 return (status);
109 }
110
111 /*
112 * __REC_FPIPE -- Get fixed length records from a pipe.
113 *
114 * Parameters:
115 * t: tree
116 * cnt: records to read
117 *
118 * Returns:
119 * RET_ERROR, RET_SUCCESS
120 */
121 int
__rec_fpipe(t,top)122 __rec_fpipe(t, top)
123 BTREE *t;
124 recno_t top;
125 {
126 DBT data;
127 recno_t nrec;
128 size_t len;
129 int ch;
130 u_char *p;
131
132 if (t->bt_rdata.size < t->bt_reclen) {
133 t->bt_rdata.data = t->bt_rdata.data == NULL ?
134 malloc(t->bt_reclen) :
135 realloc(t->bt_rdata.data, t->bt_reclen);
136 if (t->bt_rdata.data == NULL)
137 return (RET_ERROR);
138 t->bt_rdata.size = t->bt_reclen;
139 }
140 data.data = t->bt_rdata.data;
141 data.size = t->bt_reclen;
142
143 for (nrec = t->bt_nrecs; nrec < top;) {
144 len = t->bt_reclen;
145 for (p = t->bt_rdata.data;; *p++ = ch)
146 if ((ch = getc(t->bt_rfp)) == EOF || !--len) {
147 if (ch != EOF)
148 *p = ch;
149 if (len != 0)
150 memset(p, t->bt_bval, len);
151 if (__rec_iput(t,
152 nrec, &data, 0) != RET_SUCCESS)
153 return (RET_ERROR);
154 ++nrec;
155 break;
156 }
157 if (ch == EOF)
158 break;
159 }
160 if (nrec < top) {
161 F_SET(t, R_EOF);
162 return (RET_SPECIAL);
163 }
164 return (RET_SUCCESS);
165 }
166
167 /*
168 * __REC_VPIPE -- Get variable length records from a pipe.
169 *
170 * Parameters:
171 * t: tree
172 * cnt: records to read
173 *
174 * Returns:
175 * RET_ERROR, RET_SUCCESS
176 */
177 int
__rec_vpipe(t,top)178 __rec_vpipe(t, top)
179 BTREE *t;
180 recno_t top;
181 {
182 DBT data;
183 recno_t nrec;
184 indx_t len;
185 size_t sz;
186 int bval, ch;
187 u_char *p;
188
189 bval = t->bt_bval;
190 for (nrec = t->bt_nrecs; nrec < top; ++nrec) {
191 for (p = t->bt_rdata.data,
192 sz = t->bt_rdata.size;; *p++ = ch, --sz) {
193 if ((ch = getc(t->bt_rfp)) == EOF || ch == bval) {
194 data.data = t->bt_rdata.data;
195 data.size = p - (u_char *)t->bt_rdata.data;
196 if (ch == EOF && data.size == 0)
197 break;
198 if (__rec_iput(t, nrec, &data, 0)
199 != RET_SUCCESS)
200 return (RET_ERROR);
201 break;
202 }
203 if (sz == 0) {
204 len = p - (u_char *)t->bt_rdata.data;
205 t->bt_rdata.size += (sz = 256);
206 t->bt_rdata.data = t->bt_rdata.data == NULL ?
207 malloc(t->bt_rdata.size) :
208 realloc(t->bt_rdata.data, t->bt_rdata.size);
209 if (t->bt_rdata.data == NULL)
210 return (RET_ERROR);
211 p = (u_char *)t->bt_rdata.data + len;
212 }
213 }
214 if (ch == EOF)
215 break;
216 }
217 if (nrec < top) {
218 F_SET(t, R_EOF);
219 return (RET_SPECIAL);
220 }
221 return (RET_SUCCESS);
222 }
223
224 /*
225 * __REC_FMAP -- Get fixed length records from a file.
226 *
227 * Parameters:
228 * t: tree
229 * cnt: records to read
230 *
231 * Returns:
232 * RET_ERROR, RET_SUCCESS
233 */
234 int
__rec_fmap(t,top)235 __rec_fmap(t, top)
236 BTREE *t;
237 recno_t top;
238 {
239 DBT data;
240 recno_t nrec;
241 u_char *sp, *ep, *p;
242 size_t len;
243
244 if (t->bt_rdata.size < t->bt_reclen) {
245 t->bt_rdata.data = t->bt_rdata.data == NULL ?
246 malloc(t->bt_reclen) :
247 realloc(t->bt_rdata.data, t->bt_reclen);
248 if (t->bt_rdata.data == NULL)
249 return (RET_ERROR);
250 t->bt_rdata.size = t->bt_reclen;
251 }
252 data.data = t->bt_rdata.data;
253 data.size = t->bt_reclen;
254
255 sp = (u_char *)t->bt_cmap;
256 ep = (u_char *)t->bt_emap;
257 for (nrec = t->bt_nrecs; nrec < top; ++nrec) {
258 if (sp >= ep) {
259 F_SET(t, R_EOF);
260 return (RET_SPECIAL);
261 }
262 len = t->bt_reclen;
263 for (p = t->bt_rdata.data;
264 sp < ep && len > 0; *p++ = *sp++, --len);
265 if (len != 0)
266 memset(p, t->bt_bval, len);
267 if (__rec_iput(t, nrec, &data, 0) != RET_SUCCESS)
268 return (RET_ERROR);
269 }
270 t->bt_cmap = (caddr_t)sp;
271 return (RET_SUCCESS);
272 }
273
274 /*
275 * __REC_VMAP -- Get variable length records from a file.
276 *
277 * Parameters:
278 * t: tree
279 * cnt: records to read
280 *
281 * Returns:
282 * RET_ERROR, RET_SUCCESS
283 */
284 int
__rec_vmap(t,top)285 __rec_vmap(t, top)
286 BTREE *t;
287 recno_t top;
288 {
289 DBT data;
290 u_char *sp, *ep;
291 recno_t nrec;
292 int bval;
293
294 sp = (u_char *)t->bt_cmap;
295 ep = (u_char *)t->bt_emap;
296 bval = t->bt_bval;
297
298 for (nrec = t->bt_nrecs; nrec < top; ++nrec) {
299 if (sp >= ep) {
300 F_SET(t, R_EOF);
301 return (RET_SPECIAL);
302 }
303 for (data.data = sp; sp < ep && *sp != bval; ++sp);
304 data.size = sp - (u_char *)data.data;
305 if (__rec_iput(t, nrec, &data, 0) != RET_SUCCESS)
306 return (RET_ERROR);
307 ++sp;
308 }
309 t->bt_cmap = (caddr_t)sp;
310 return (RET_SUCCESS);
311 }
312