db/recno/rec_utils.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  * Redistribution and use in source and binary forms, with or without
  27  * modification, are permitted provided that the following conditions
  28  * are met:
  29  * 1. Redistributions of source code must retain the above copyright
  30  *    notice, this list of conditions and the following disclaimer.
  31  * 2. Redistributions in binary form must reproduce the above copyright
  32  *    notice, this list of conditions and the following disclaimer in the
  33  *    documentation and/or other materials provided with the distribution.
  34  * 3. All advertising materials mentioning features or use of this software
  35  *    must display the following acknowledgement:
  36  *      This product includes software developed by the University of
  37  *      California, Berkeley and its contributors.
  38  * 4. Neither the name of the University nor the names of its contributors
  39  *    may be used to endorse or promote products derived from this software
  40  *    without specific prior written permission.
  41  *
  42  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  43  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  44  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  45  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  46  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  47  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  48  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  49  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  50  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  51  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  52  * SUCH DAMAGE.
  53  */
  54
  55
  56 #include <sys/param.h>
  57
  58 #include <stdio.h>
  59 #include <stdlib.h>
  60 #include <string.h>
  61
  62 #include <db.h>
  63 #include "recno.h"
  64
  65 /*
  66  * __REC_RET -- Build return data as a result of search or scan.
  67  *
  68  * Parameters:
  69  *      t:      tree
  70  *      d:      LEAF to be returned to the user.
  71  *      data:   user's data structure
  72  *
  73  * Returns:
  74  *      RET_SUCCESS, RET_ERROR.
  75  */
  76 int
  77 __rec_ret(t, e, nrec, key, data)
  78         BTREE *t;
  79         EPG *e;
  80         recno_t nrec;
  81         DBT *key, *data;
  82 {
  83         register RLEAF *rl;
  84         register void *p;
  85
  86         if (data == NULL)
  87                 goto retkey;
  88
  89         rl = GETRLEAF(e->page, e->index);
  90
  91         /*
  92          * We always copy big data to make it contigous.  Otherwise, we
  93          * leave the page pinned and don't copy unless the user specified
  94          * concurrent access.
  95          */
  96         if (rl->flags & P_BIGDATA) {
  97                 if (__ovfl_get(t, rl->bytes,
  98                     &data->size, &t->bt_dbuf, &t->bt_dbufsz))
  99                         return (RET_ERROR);
 100                 data->data = t->bt_dbuf;
 101         } else if (ISSET(t, B_DB_LOCK)) {
 102                 /* Use +1 in case the first record retrieved is 0 length. */
 103                 if (rl->dsize + 1 > t->bt_dbufsz) {
 104                         if ((p =
 105                             (void *)realloc(t->bt_dbuf, rl->dsize + 1)) == NULL)
 106                                 return (RET_ERROR);
 107                         t->bt_dbuf = p;
 108                         t->bt_dbufsz = rl->dsize + 1;
 109                 }
 110                 memmove(t->bt_dbuf, rl->bytes, rl->dsize);
 111                 data->size = rl->dsize;
 112                 data->data = t->bt_dbuf;
 113         } else {
 114                 data->size = rl->dsize;
 115                 data->data = rl->bytes;
 116         }
 117
 118 retkey: if (key == NULL)
 119                 return (RET_SUCCESS);
 120
 121         /* We have to copy the key, it's not on the page. */
 122         if (sizeof(recno_t) > t->bt_kbufsz) {
 123                 if ((p = (void *)realloc(t->bt_kbuf, sizeof(recno_t))) == NULL)
 124                         return (RET_ERROR);
 125                 t->bt_kbuf = p;
 126                 t->bt_kbufsz = sizeof(recno_t);
 127         }
 128         memmove(t->bt_kbuf, &nrec, sizeof(recno_t));
 129         key->size = sizeof(recno_t);
 130         key->data = t->bt_kbuf;
 131         return (RET_SUCCESS);
 132 }