xref: /386bsd/usr/src/lib/libc/db/btree/bt_close.c (revision a2142627)
1 /*-
2  * Copyright (c) 1990 The Regents of the University of California.
3  * All rights reserved.
4  *
5  * This code is derived from software contributed to Berkeley by
6  * Mike Olson.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. All advertising materials mentioning features or use of this software
17  *    must display the following acknowledgement:
18  *	This product includes software developed by the University of
19  *	California, Berkeley and its contributors.
20  * 4. Neither the name of the University nor the names of its contributors
21  *    may be used to endorse or promote products derived from this software
22  *    without specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  */
36 
37 #if defined(LIBC_SCCS) && !defined(lint)
38 static char sccsid[] = "@(#)bt_close.c	5.12 (Berkeley) 5/16/93";
39 #endif /* LIBC_SCCS and not lint */
40 
41 #include <sys/param.h>
42 
43 #include <errno.h>
44 #include <stdio.h>
45 #include <stdlib.h>
46 #include <string.h>
47 #include <unistd.h>
48 
49 #include <db.h>
50 #include "btree.h"
51 
52 static int bt_meta __P((BTREE *));
53 
54 /*
55  * BT_CLOSE -- Close a btree.
56  *
57  * Parameters:
58  *	dbp:	pointer to access method
59  *
60  * Returns:
61  *	RET_ERROR, RET_SUCCESS
62  */
63 int
__bt_close(dbp)64 __bt_close(dbp)
65 	DB *dbp;
66 {
67 	BTREE *t;
68 	int fd;
69 
70 	t = dbp->internal;
71 
72 	/*
73 	 * Delete any already deleted record that we've been saving
74 	 * because the cursor pointed to it.
75 	 */
76 	if (ISSET(t, B_DELCRSR) && __bt_crsrdel(t, &t->bt_bcursor))
77 		return (RET_ERROR);
78 
79 	if (__bt_sync(dbp, 0) == RET_ERROR)
80 		return (RET_ERROR);
81 
82 	if (mpool_close(t->bt_mp) == RET_ERROR)
83 		return (RET_ERROR);
84 
85 	if (t->bt_stack)
86 		free(t->bt_stack);
87 	if (t->bt_kbuf)
88 		free(t->bt_kbuf);
89 	if (t->bt_dbuf)
90 		free(t->bt_dbuf);
91 
92 	fd = t->bt_fd;
93 	free(t);
94 	free(dbp);
95 	return (close(fd) ? RET_ERROR : RET_SUCCESS);
96 }
97 
98 /*
99  * BT_SYNC -- sync the btree to disk.
100  *
101  * Parameters:
102  *	dbp:	pointer to access method
103  *
104  * Returns:
105  *	RET_SUCCESS, RET_ERROR.
106  */
107 int
__bt_sync(dbp,flags)108 __bt_sync(dbp, flags)
109 	const DB *dbp;
110 	u_int flags;
111 {
112 	BTREE *t;
113 	int status;
114 	PAGE *h;
115 	void *p;
116 
117 	if (flags != 0) {
118 		errno = EINVAL;
119 		return (RET_ERROR);
120 	}
121 
122 	t = dbp->internal;
123 
124 	if (ISSET(t, B_INMEM | B_RDONLY) || !ISSET(t, B_MODIFIED))
125 		return (RET_SUCCESS);
126 
127 	if (ISSET(t, B_METADIRTY) && bt_meta(t) == RET_ERROR)
128 		return (RET_ERROR);
129 
130 	/*
131 	 * Nastiness.  If the cursor has been marked for deletion, but not
132 	 * actually deleted, we have to make a copy of the page, delete the
133 	 * key/data item, sync the file, and then restore the original page
134 	 * contents.
135 	 */
136 	if (ISSET(t, B_DELCRSR)) {
137 		if ((p = malloc(t->bt_psize)) == NULL)
138 			return (RET_ERROR);
139 		if ((h = mpool_get(t->bt_mp, t->bt_bcursor.pgno, 0)) == NULL)
140 			return (RET_ERROR);
141 		memmove(p, h, t->bt_psize);
142 		if ((status =
143 		    __bt_dleaf(t, h, t->bt_bcursor.index)) == RET_ERROR)
144 			goto ecrsr;
145 		mpool_put(t->bt_mp, h, MPOOL_DIRTY);
146 	}
147 
148 	if ((status = mpool_sync(t->bt_mp)) == RET_SUCCESS)
149 		CLR(t, B_MODIFIED);
150 
151 ecrsr:	if (ISSET(t, B_DELCRSR)) {
152 		if ((h = mpool_get(t->bt_mp, t->bt_bcursor.pgno, 0)) == NULL)
153 			return (RET_ERROR);
154 		memmove(h, p, t->bt_psize);
155 		free(p);
156 		mpool_put(t->bt_mp, h, MPOOL_DIRTY);
157 	}
158 	return (status);
159 }
160 
161 /*
162  * BT_META -- write the tree meta data to disk.
163  *
164  * Parameters:
165  *	t:	tree
166  *
167  * Returns:
168  *	RET_ERROR, RET_SUCCESS
169  */
170 static int
bt_meta(t)171 bt_meta(t)
172 	BTREE *t;
173 {
174 	BTMETA m;
175 	void *p;
176 
177 	if ((p = mpool_get(t->bt_mp, P_META, 0)) == NULL)
178 		return (RET_ERROR);
179 
180 	/* Fill in metadata. */
181 	m.m_magic = BTREEMAGIC;
182 	m.m_version = BTREEVERSION;
183 	m.m_psize = t->bt_psize;
184 	m.m_free = t->bt_free;
185 	m.m_nrecs = t->bt_nrecs;
186 	m.m_flags = t->bt_flags & SAVEMETA;
187 
188 	memmove(p, &m, sizeof(BTMETA));
189 	mpool_put(t->bt_mp, p, MPOOL_DIRTY);
190 	return (RET_SUCCESS);
191 }
192