db.subproj/btree.subproj/bt_close.c

   1 /*
   2  * Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * The contents of this file constitute Original Code as defined in and
   7  * are subject to the Apple Public Source License Version 1.1 (the
   8  * "License").  You may not use this file except in compliance with the
   9  * License.  Please obtain a copy of the License at
  10  * http://www.apple.com/publicsource and read it before using this file.
  11  *
  12  * This Original Code and all software distributed under the License are
  13  * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  14  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  15  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  16  * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
  17  * License for the specific language governing rights and limitations
  18  * under the License.
  19  *
  20  * @APPLE_LICENSE_HEADER_END@
  21  */
  22 /*
  23  * Copyright (c) 1990, 1993
  24  *      The Regents of the University of California.  All rights reserved.
  25  *
  26  * This code is derived from software contributed to Berkeley by
  27  * Mike Olson.
  28  *
  29  * Redistribution and use in source and binary forms, with or without
  30  * modification, are permitted provided that the following conditions
  31  * are met:
  32  * 1. Redistributions of source code must retain the above copyright
  33  *    notice, this list of conditions and the following disclaimer.
  34  * 2. Redistributions in binary form must reproduce the above copyright
  35  *    notice, this list of conditions and the following disclaimer in the
  36  *    documentation and/or other materials provided with the distribution.
  37  * 3. All advertising materials mentioning features or use of this software
  38  *    must display the following acknowledgement:
  39  *      This product includes software developed by the University of
  40  *      California, Berkeley and its contributors.
  41  * 4. Neither the name of the University nor the names of its contributors
  42  *    may be used to endorse or promote products derived from this software
  43  *    without specific prior written permission.
  44  *
  45  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  46  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  47  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  48  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  49  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  50  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  51  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  52  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  53  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  54  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  55  * SUCH DAMAGE.
  56  */
  57
  58
  59 #include <sys/param.h>
  60
  61 #include <errno.h>
  62 #include <stdio.h>
  63 #include <stdlib.h>
  64 #include <string.h>
  65 #include <unistd.h>
  66
  67 #include <db.h>
  68 #include "btree.h"
  69
  70 static int bt_meta __P((BTREE *));
  71
  72 /*
  73  * BT_CLOSE -- Close a btree.
  74  *
  75  * Parameters:
  76  *      dbp:    pointer to access method
  77  *
  78  * Returns:
  79  *      RET_ERROR, RET_SUCCESS
  80  */
  81 int
  82 __bt_close(dbp)
  83         DB *dbp;
  84 {
  85         BTREE *t;
  86         int fd;
  87
  88         t = dbp->internal;
  89
  90         /* Toss any page pinned across calls. */
  91         if (t->bt_pinned != NULL) {
  92                 mpool_put(t->bt_mp, t->bt_pinned, 0);
  93                 t->bt_pinned = NULL;
  94         }
  95
  96         /*
  97          * Delete any already deleted record that we've been saving
  98          * because the cursor pointed to it.
  99          */
 100         if (ISSET(t, B_DELCRSR) && __bt_crsrdel(t, &t->bt_bcursor))
 101                 return (RET_ERROR);
 102
 103         if (__bt_sync(dbp, 0) == RET_ERROR)
 104                 return (RET_ERROR);
 105
 106         if (mpool_close(t->bt_mp) == RET_ERROR)
 107                 return (RET_ERROR);
 108
 109         if (t->bt_stack)
 110                 free(t->bt_stack);
 111         if (t->bt_kbuf)
 112                 free(t->bt_kbuf);
 113         if (t->bt_dbuf)
 114                 free(t->bt_dbuf);
 115
 116         fd = t->bt_fd;
 117         free(t);
 118         free(dbp);
 119         return (close(fd) ? RET_ERROR : RET_SUCCESS);
 120 }
 121
 122 /*
 123  * BT_SYNC -- sync the btree to disk.
 124  *
 125  * Parameters:
 126  *      dbp:    pointer to access method
 127  *
 128  * Returns:
 129  *      RET_SUCCESS, RET_ERROR.
 130  */
 131 int
 132 __bt_sync(dbp, flags)
 133         const DB *dbp;
 134         u_int flags;
 135 {
 136         BTREE *t;
 137         int status;
 138         PAGE *h;
 139         void *p;
 140
 141         t = dbp->internal;
 142
 143         /* Toss any page pinned across calls. */
 144         if (t->bt_pinned != NULL) {
 145                 mpool_put(t->bt_mp, t->bt_pinned, 0);
 146                 t->bt_pinned = NULL;
 147         }
 148
 149         /* Sync doesn't currently take any flags. */
 150         if (flags != 0) {
 151                 errno = EINVAL;
 152                 return (RET_ERROR);
 153         }
 154
 155         if (ISSET(t, B_INMEM | B_RDONLY) || !ISSET(t, B_MODIFIED))
 156                 return (RET_SUCCESS);
 157
 158         if (ISSET(t, B_METADIRTY) && bt_meta(t) == RET_ERROR)
 159                 return (RET_ERROR);
 160
 161         /*
 162          * Nastiness.  If the cursor has been marked for deletion, but not
 163          * actually deleted, we have to make a copy of the page, delete the
 164          * key/data item, sync the file, and then restore the original page
 165          * contents.
 166          */
 167         if (ISSET(t, B_DELCRSR)) {
 168                 if ((p = (void *)malloc(t->bt_psize)) == NULL)
 169                         return (RET_ERROR);
 170                 if ((h = mpool_get(t->bt_mp, t->bt_bcursor.pgno, 0)) == NULL)
 171                         return (RET_ERROR);
 172                 memmove(p, h, t->bt_psize);
 173                 if ((status =
 174                     __bt_dleaf(t, h, t->bt_bcursor.index)) == RET_ERROR)
 175                         goto ecrsr;
 176                 mpool_put(t->bt_mp, h, MPOOL_DIRTY);
 177         }
 178
 179         if ((status = mpool_sync(t->bt_mp)) == RET_SUCCESS)
 180                 CLR(t, B_MODIFIED);
 181
 182 ecrsr:  if (ISSET(t, B_DELCRSR)) {
 183                 if ((h = mpool_get(t->bt_mp, t->bt_bcursor.pgno, 0)) == NULL)
 184                         return (RET_ERROR);
 185                 memmove(h, p, t->bt_psize);
 186                 free(p);
 187                 mpool_put(t->bt_mp, h, MPOOL_DIRTY);
 188         }
 189         return (status);
 190 }
 191
 192 /*
 193  * BT_META -- write the tree meta data to disk.
 194  *
 195  * Parameters:
 196  *      t:      tree
 197  *
 198  * Returns:
 199  *      RET_ERROR, RET_SUCCESS
 200  */
 201 static int
 202 bt_meta(t)
 203         BTREE *t;
 204 {
 205         BTMETA m;
 206         void *p;
 207
 208         if ((p = mpool_get(t->bt_mp, P_META, 0)) == NULL)
 209                 return (RET_ERROR);
 210
 211         /* Fill in metadata. */
 212         m.m_magic = BTREEMAGIC;
 213         m.m_version = BTREEVERSION;
 214         m.m_psize = t->bt_psize;
 215         m.m_free = t->bt_free;
 216         m.m_nrecs = t->bt_nrecs;
 217         m.m_flags = t->bt_flags & SAVEMETA;
 218
 219         memmove(p, &m, sizeof(BTMETA));
 220         mpool_put(t->bt_mp, p, MPOOL_DIRTY);
 221         return (RET_SUCCESS);
 222 }