xref: /original-bsd/lib/libc/db/btree/bt_close.c (revision 05bf53f3)
1 /*-
2  * Copyright (c) 1990, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * This code is derived from software contributed to Berkeley by
6  * Mike Olson.
7  *
8  * %sccs.include.redist.c%
9  */
10 
11 #if defined(LIBC_SCCS) && !defined(lint)
12 static char sccsid[] = "@(#)bt_close.c	8.1 (Berkeley) 06/04/93";
13 #endif /* LIBC_SCCS and not lint */
14 
15 #include <sys/param.h>
16 
17 #include <errno.h>
18 #include <stdio.h>
19 #include <stdlib.h>
20 #include <string.h>
21 #include <unistd.h>
22 
23 #include <db.h>
24 #include "btree.h"
25 
26 static int bt_meta __P((BTREE *));
27 
28 /*
29  * BT_CLOSE -- Close a btree.
30  *
31  * Parameters:
32  *	dbp:	pointer to access method
33  *
34  * Returns:
35  *	RET_ERROR, RET_SUCCESS
36  */
37 int
38 __bt_close(dbp)
39 	DB *dbp;
40 {
41 	BTREE *t;
42 	int fd;
43 
44 	t = dbp->internal;
45 
46 	/*
47 	 * Delete any already deleted record that we've been saving
48 	 * because the cursor pointed to it.
49 	 */
50 	if (ISSET(t, B_DELCRSR) && __bt_crsrdel(t, &t->bt_bcursor))
51 		return (RET_ERROR);
52 
53 	if (__bt_sync(dbp, 0) == RET_ERROR)
54 		return (RET_ERROR);
55 
56 	if (mpool_close(t->bt_mp) == RET_ERROR)
57 		return (RET_ERROR);
58 
59 	if (t->bt_stack)
60 		free(t->bt_stack);
61 	if (t->bt_kbuf)
62 		free(t->bt_kbuf);
63 	if (t->bt_dbuf)
64 		free(t->bt_dbuf);
65 
66 	fd = t->bt_fd;
67 	free(t);
68 	free(dbp);
69 	return (close(fd) ? RET_ERROR : RET_SUCCESS);
70 }
71 
72 /*
73  * BT_SYNC -- sync the btree to disk.
74  *
75  * Parameters:
76  *	dbp:	pointer to access method
77  *
78  * Returns:
79  *	RET_SUCCESS, RET_ERROR.
80  */
81 int
82 __bt_sync(dbp, flags)
83 	const DB *dbp;
84 	u_int flags;
85 {
86 	BTREE *t;
87 	int status;
88 	PAGE *h;
89 	void *p;
90 
91 	if (flags != 0) {
92 		errno = EINVAL;
93 		return (RET_ERROR);
94 	}
95 
96 	t = dbp->internal;
97 
98 	if (ISSET(t, B_INMEM | B_RDONLY) || !ISSET(t, B_MODIFIED))
99 		return (RET_SUCCESS);
100 
101 	if (ISSET(t, B_METADIRTY) && bt_meta(t) == RET_ERROR)
102 		return (RET_ERROR);
103 
104 	/*
105 	 * Nastiness.  If the cursor has been marked for deletion, but not
106 	 * actually deleted, we have to make a copy of the page, delete the
107 	 * key/data item, sync the file, and then restore the original page
108 	 * contents.
109 	 */
110 	if (ISSET(t, B_DELCRSR)) {
111 		if ((p = malloc(t->bt_psize)) == NULL)
112 			return (RET_ERROR);
113 		if ((h = mpool_get(t->bt_mp, t->bt_bcursor.pgno, 0)) == NULL)
114 			return (RET_ERROR);
115 		memmove(p, h, t->bt_psize);
116 		if ((status =
117 		    __bt_dleaf(t, h, t->bt_bcursor.index)) == RET_ERROR)
118 			goto ecrsr;
119 		mpool_put(t->bt_mp, h, MPOOL_DIRTY);
120 	}
121 
122 	if ((status = mpool_sync(t->bt_mp)) == RET_SUCCESS)
123 		CLR(t, B_MODIFIED);
124 
125 ecrsr:	if (ISSET(t, B_DELCRSR)) {
126 		if ((h = mpool_get(t->bt_mp, t->bt_bcursor.pgno, 0)) == NULL)
127 			return (RET_ERROR);
128 		memmove(h, p, t->bt_psize);
129 		free(p);
130 		mpool_put(t->bt_mp, h, MPOOL_DIRTY);
131 	}
132 	return (status);
133 }
134 
135 /*
136  * BT_META -- write the tree meta data to disk.
137  *
138  * Parameters:
139  *	t:	tree
140  *
141  * Returns:
142  *	RET_ERROR, RET_SUCCESS
143  */
144 static int
145 bt_meta(t)
146 	BTREE *t;
147 {
148 	BTMETA m;
149 	void *p;
150 
151 	if ((p = mpool_get(t->bt_mp, P_META, 0)) == NULL)
152 		return (RET_ERROR);
153 
154 	/* Fill in metadata. */
155 	m.m_magic = BTREEMAGIC;
156 	m.m_version = BTREEVERSION;
157 	m.m_psize = t->bt_psize;
158 	m.m_free = t->bt_free;
159 	m.m_nrecs = t->bt_nrecs;
160 	m.m_flags = t->bt_flags & SAVEMETA;
161 
162 	memmove(p, &m, sizeof(BTMETA));
163 	mpool_put(t->bt_mp, p, MPOOL_DIRTY);
164 	return (RET_SUCCESS);
165 }
166