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bt_close.c revision 1.12 
      1 /*	$NetBSD: bt_close.c,v 1.12 2007/02/03 23:46:09 christos Exp $	*/
      2 
      3 /*-
      4  * Copyright (c) 1990, 1993, 1994
      5  *	The Regents of the University of California.  All rights reserved.
      6  *
      7  * This code is derived from software contributed to Berkeley by
      8  * Mike Olson.
      9  *
     10  * Redistribution and use in source and binary forms, with or without
     11  * modification, are permitted provided that the following conditions
     12  * are met:
     13  * 1. Redistributions of source code must retain the above copyright
     14  *    notice, this list of conditions and the following disclaimer.
     15  * 2. Redistributions in binary form must reproduce the above copyright
     16  *    notice, this list of conditions and the following disclaimer in the
     17  *    documentation and/or other materials provided with the distribution.
     18  * 3. Neither the name of the University nor the names of its contributors
     19  *    may be used to endorse or promote products derived from this software
     20  *    without specific prior written permission.
     21  *
     22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     32  * SUCH DAMAGE.
     33  */
     34 
     35 #include <sys/cdefs.h>
     36 #if defined(LIBC_SCCS) && !defined(lint)
     37 #if 0
     38 static char sccsid[] = "@(#)bt_close.c	8.7 (Berkeley) 8/17/94";
     39 #else
     40 __RCSID("$NetBSD: bt_close.c,v 1.12 2007/02/03 23:46:09 christos Exp $");
     41 #endif
     42 #endif /* LIBC_SCCS and not lint */
     43 
     44 #include "namespace.h"
     45 
     46 #include <assert.h>
     47 #include <errno.h>
     48 #include <stdio.h>
     49 #include <stdlib.h>
     50 #include <string.h>
     51 #include <unistd.h>
     52 
     53 #include <db.h>
     54 #include "btree.h"
     55 
     56 static int bt_meta(BTREE *);
     57 
     58 /*
     59  * BT_CLOSE -- Close a btree.
     60  *
     61  * Parameters:
     62  *	dbp:	pointer to access method
     63  *
     64  * Returns:
     65  *	RET_ERROR, RET_SUCCESS
     66  */
     67 int
     68 __bt_close(DB *dbp)
     69 {
     70 	BTREE *t;
     71 	int fd;
     72 
     73 	t = dbp->internal;
     74 
     75 	/* Toss any page pinned across calls. */
     76 	if (t->bt_pinned != NULL) {
     77 		mpool_put(t->bt_mp, t->bt_pinned, 0);
     78 		t->bt_pinned = NULL;
     79 	}
     80 
     81 	/* Sync the tree. */
     82 	if (__bt_sync(dbp, 0) == RET_ERROR)
     83 		return (RET_ERROR);
     84 
     85 	/* Close the memory pool. */
     86 	if (mpool_close(t->bt_mp) == RET_ERROR)
     87 		return (RET_ERROR);
     88 
     89 	/* Free random memory. */
     90 	if (t->bt_cursor.key.data != NULL) {
     91 		free(t->bt_cursor.key.data);
     92 		t->bt_cursor.key.size = 0;
     93 		t->bt_cursor.key.data = NULL;
     94 	}
     95 	if (t->bt_rkey.data) {
     96 		free(t->bt_rkey.data);
     97 		t->bt_rkey.size = 0;
     98 		t->bt_rkey.data = NULL;
     99 	}
    100 	if (t->bt_rdata.data) {
    101 		free(t->bt_rdata.data);
    102 		t->bt_rdata.size = 0;
    103 		t->bt_rdata.data = NULL;
    104 	}
    105 
    106 	fd = t->bt_fd;
    107 	free(t);
    108 	free(dbp);
    109 	return (close(fd) ? RET_ERROR : RET_SUCCESS);
    110 }
    111 
    112 /*
    113  * BT_SYNC -- sync the btree to disk.
    114  *
    115  * Parameters:
    116  *	dbp:	pointer to access method
    117  *
    118  * Returns:
    119  *	RET_SUCCESS, RET_ERROR.
    120  */
    121 int
    122 __bt_sync(const DB *dbp, u_int flags)
    123 {
    124 	BTREE *t;
    125 	int status;
    126 
    127 	t = dbp->internal;
    128 
    129 	/* Toss any page pinned across calls. */
    130 	if (t->bt_pinned != NULL) {
    131 		mpool_put(t->bt_mp, t->bt_pinned, 0);
    132 		t->bt_pinned = NULL;
    133 	}
    134 
    135 	/* Sync doesn't currently take any flags. */
    136 	if (flags != 0) {
    137 		errno = EINVAL;
    138 		return (RET_ERROR);
    139 	}
    140 
    141 	if (F_ISSET(t, B_INMEM | B_RDONLY) || !F_ISSET(t, B_MODIFIED))
    142 		return (RET_SUCCESS);
    143 
    144 	if (F_ISSET(t, B_METADIRTY) && bt_meta(t) == RET_ERROR)
    145 		return (RET_ERROR);
    146 
    147 	if ((status = mpool_sync(t->bt_mp)) == RET_SUCCESS)
    148 		F_CLR(t, B_MODIFIED);
    149 
    150 	return (status);
    151 }
    152 
    153 /*
    154  * BT_META -- write the tree meta data to disk.
    155  *
    156  * Parameters:
    157  *	t:	tree
    158  *
    159  * Returns:
    160  *	RET_ERROR, RET_SUCCESS
    161  */
    162 static int
    163 bt_meta(BTREE *t)
    164 {
    165 	BTMETA m;
    166 	void *p;
    167 
    168 	if ((p = mpool_get(t->bt_mp, P_META, 0)) == NULL)
    169 		return (RET_ERROR);
    170 
    171 	/* Fill in metadata. */
    172 	m.magic = BTREEMAGIC;
    173 	m.version = BTREEVERSION;
    174 	m.psize = t->bt_psize;
    175 	m.free = t->bt_free;
    176 	m.nrecs = t->bt_nrecs;
    177 	m.flags = F_ISSET(t, SAVEMETA);
    178 
    179 	memmove(p, &m, sizeof(BTMETA));
    180 	mpool_put(t->bt_mp, p, MPOOL_DIRTY);
    181 	return (RET_SUCCESS);
    182 }
    183