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