db/recno/rec_utils.c

   1 /*
   2  * Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * Copyright (c) 1999-2003 Apple Computer, Inc.  All Rights Reserved.
   7  *
   8  * This file contains Original Code and/or Modifications of Original Code
   9  * as defined in and that are subject to the Apple Public Source License
  10  * Version 2.0 (the 'License'). You may not use this file except in
  11  * compliance with the License. Please obtain a copy of the License at
  12  * http://www.opensource.apple.com/apsl/ and read it before using this
  13  * file.
  14  *
  15  * The Original Code and all software distributed under the License are
  16  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  17  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  18  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  20  * Please see the License for the specific language governing rights and
  21  * limitations under the License.
  22  *
  23  * @APPLE_LICENSE_HEADER_END@
  24  */
  25 /*
  26  * Copyright (c) 1990, 1993
  27  *      The Regents of the University of California.  All rights reserved.
  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 <stdio.h>
  62 #include <stdlib.h>
  63 #include <string.h>
  64
  65 #include <db.h>
  66 #include "recno.h"
  67
  68 /*
  69  * __REC_RET -- Build return data as a result of search or scan.
  70  *
  71  * Parameters:
  72  *      t:      tree
  73  *      d:      LEAF to be returned to the user.
  74  *      data:   user's data structure
  75  *
  76  * Returns:
  77  *      RET_SUCCESS, RET_ERROR.
  78  */
  79 int
  80 __rec_ret(t, e, nrec, key, data)
  81         BTREE *t;
  82         EPG *e;
  83         recno_t nrec;
  84         DBT *key, *data;
  85 {
  86         register RLEAF *rl;
  87         register void *p;
  88
  89         if (data == NULL)
  90                 goto retkey;
  91
  92         rl = GETRLEAF(e->page, e->index);
  93
  94         /*
  95          * We always copy big data to make it contigous.  Otherwise, we
  96          * leave the page pinned and don't copy unless the user specified
  97          * concurrent access.
  98          */
  99         if (rl->flags & P_BIGDATA) {
 100                 if (__ovfl_get(t, rl->bytes,
 101                     &data->size, &t->bt_dbuf, &t->bt_dbufsz))
 102                         return (RET_ERROR);
 103                 data->data = t->bt_dbuf;
 104         } else if (ISSET(t, B_DB_LOCK)) {
 105                 /* Use +1 in case the first record retrieved is 0 length. */
 106                 if (rl->dsize + 1 > t->bt_dbufsz) {
 107                         if ((p =
 108                             (void *)realloc(t->bt_dbuf, rl->dsize + 1)) == NULL)
 109                                 return (RET_ERROR);
 110                         t->bt_dbuf = p;
 111                         t->bt_dbufsz = rl->dsize + 1;
 112                 }
 113                 memmove(t->bt_dbuf, rl->bytes, rl->dsize);
 114                 data->size = rl->dsize;
 115                 data->data = t->bt_dbuf;
 116         } else {
 117                 data->size = rl->dsize;
 118                 data->data = rl->bytes;
 119         }
 120
 121 retkey: if (key == NULL)
 122                 return (RET_SUCCESS);
 123
 124         /* We have to copy the key, it's not on the page. */
 125         if (sizeof(recno_t) > t->bt_kbufsz) {
 126                 if ((p = (void *)realloc(t->bt_kbuf, sizeof(recno_t))) == NULL)
 127                         return (RET_ERROR);
 128                 t->bt_kbuf = p;
 129                 t->bt_kbufsz = sizeof(recno_t);
 130         }
 131         memmove(t->bt_kbuf, &nrec, sizeof(recno_t));
 132         key->size = sizeof(recno_t);
 133         key->data = t->bt_kbuf;
 134         return (RET_SUCCESS);
 135 }