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rec_put.c revision 1.4
      1 /*-
      2  * Copyright (c) 1990, 1993
      3  *	The Regents of the University of California.  All rights reserved.
      4  *
      5  * Redistribution and use in source and binary forms, with or without
      6  * modification, are permitted provided that the following conditions
      7  * are met:
      8  * 1. Redistributions of source code must retain the above copyright
      9  *    notice, this list of conditions and the following disclaimer.
     10  * 2. Redistributions in binary form must reproduce the above copyright
     11  *    notice, this list of conditions and the following disclaimer in the
     12  *    documentation and/or other materials provided with the distribution.
     13  * 3. All advertising materials mentioning features or use of this software
     14  *    must display the following acknowledgement:
     15  *	This product includes software developed by the University of
     16  *	California, Berkeley and its contributors.
     17  * 4. Neither the name of the University nor the names of its contributors
     18  *    may be used to endorse or promote products derived from this software
     19  *    without specific prior written permission.
     20  *
     21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     31  * SUCH DAMAGE.
     32  */
     33 
     34 #if defined(LIBC_SCCS) && !defined(lint)
     35 /* from: static char sccsid[] = "@(#)rec_put.c	8.2 (Berkeley) 9/7/93"; */
     36 static char *rcsid = "$Id: rec_put.c,v 1.4 1993/09/09 02:42:26 cgd Exp $";
     37 #endif /* LIBC_SCCS and not lint */
     38 
     39 #include <sys/types.h>
     40 
     41 #include <errno.h>
     42 #include <stdio.h>
     43 #include <stdlib.h>
     44 #include <string.h>
     45 
     46 #include <db.h>
     47 #include "recno.h"
     48 
     49 /*
     50  * __REC_PUT -- Add a recno item to the tree.
     51  *
     52  * Parameters:
     53  *	dbp:	pointer to access method
     54  *	key:	key
     55  *	data:	data
     56  *	flag:	R_CURSOR, R_IAFTER, R_IBEFORE, R_NOOVERWRITE
     57  *
     58  * Returns:
     59  *	RET_ERROR, RET_SUCCESS and RET_SPECIAL if the key is
     60  *	already in the tree and R_NOOVERWRITE specified.
     61  */
     62 int
     63 __rec_put(dbp, key, data, flags)
     64 	const DB *dbp;
     65 	DBT *key;
     66 	const DBT *data;
     67 	u_int flags;
     68 {
     69 	BTREE *t;
     70 	DBT tdata;
     71 	recno_t nrec;
     72 	int status;
     73 
     74 	t = dbp->internal;
     75 
     76 	/* Toss any page pinned across calls. */
     77 	if (t->bt_pinned != NULL) {
     78 		mpool_put(t->bt_mp, t->bt_pinned, 0);
     79 		t->bt_pinned = NULL;
     80 	}
     81 
     82 	switch (flags) {
     83 	case R_CURSOR:
     84 		if (!ISSET(t, B_SEQINIT))
     85 			goto einval;
     86 		nrec = t->bt_rcursor;
     87 		break;
     88 	case R_SETCURSOR:
     89 		if ((nrec = *(recno_t *)key->data) == 0)
     90 			goto einval;
     91 		break;
     92 	case R_IAFTER:
     93 		if ((nrec = *(recno_t *)key->data) == 0) {
     94 			nrec = 1;
     95 			flags = R_IBEFORE;
     96 		}
     97 		break;
     98 	case 0:
     99 	case R_IBEFORE:
    100 		if ((nrec = *(recno_t *)key->data) == 0)
    101 			goto einval;
    102 		break;
    103 	case R_NOOVERWRITE:
    104 		if ((nrec = *(recno_t *)key->data) == 0)
    105 			goto einval;
    106 		if (nrec <= t->bt_nrecs)
    107 			return (RET_SPECIAL);
    108 		break;
    109 	default:
    110 einval:		errno = EINVAL;
    111 		return (RET_ERROR);
    112 	}
    113 
    114 	/*
    115 	 * Make sure that records up to and including the put record are
    116 	 * already in the database.  If skipping records, create empty ones.
    117 	 */
    118 	if (nrec > t->bt_nrecs) {
    119 		if (!ISSET(t, R_EOF | R_INMEM) &&
    120 		    t->bt_irec(t, nrec) == RET_ERROR)
    121 			return (RET_ERROR);
    122 		if (nrec > t->bt_nrecs + 1) {
    123 			tdata.data = NULL;
    124 			tdata.size = 0;
    125 			while (nrec > t->bt_nrecs + 1)
    126 				if (__rec_iput(t,
    127 				    t->bt_nrecs, &tdata, 0) != RET_SUCCESS)
    128 					return (RET_ERROR);
    129 		}
    130 	}
    131 
    132 	if ((status = __rec_iput(t, nrec - 1, data, flags)) != RET_SUCCESS)
    133 		return (status);
    134 
    135 	if (flags == R_SETCURSOR)
    136 		t->bt_rcursor = nrec;
    137 
    138 	SET(t, R_MODIFIED);
    139 	return (__rec_ret(t, NULL, nrec, key, NULL));
    140 }
    141 
    142 /*
    143  * __REC_IPUT -- Add a recno item to the tree.
    144  *
    145  * Parameters:
    146  *	t:	tree
    147  *	nrec:	record number
    148  *	data:	data
    149  *
    150  * Returns:
    151  *	RET_ERROR, RET_SUCCESS
    152  */
    153 int
    154 __rec_iput(t, nrec, data, flags)
    155 	BTREE *t;
    156 	recno_t nrec;
    157 	const DBT *data;
    158 	u_int flags;
    159 {
    160 	DBT tdata;
    161 	EPG *e;
    162 	PAGE *h;
    163 	indx_t index, nxtindex;
    164 	pgno_t pg;
    165 	size_t nbytes;
    166 	int dflags, status;
    167 	char *dest, db[NOVFLSIZE];
    168 
    169 	/*
    170 	 * If the data won't fit on a page, store it on indirect pages.
    171 	 *
    172 	 * XXX
    173 	 * If the insert fails later on, these pages aren't recovered.
    174 	 */
    175 	if (data->size > t->bt_ovflsize) {
    176 		if (__ovfl_put(t, data, &pg) == RET_ERROR)
    177 			return (RET_ERROR);
    178 		tdata.data = db;
    179 		tdata.size = NOVFLSIZE;
    180 		*(pgno_t *)db = pg;
    181 		*(size_t *)(db + sizeof(pgno_t)) = data->size;
    182 		dflags = P_BIGDATA;
    183 		data = &tdata;
    184 	} else
    185 		dflags = 0;
    186 
    187 	/* __rec_search pins the returned page. */
    188 	if ((e = __rec_search(t, nrec,
    189 	    nrec > t->bt_nrecs || flags == R_IAFTER || flags == R_IBEFORE ?
    190 	    SINSERT : SEARCH)) == NULL)
    191 		return (RET_ERROR);
    192 
    193 	h = e->page;
    194 	index = e->index;
    195 
    196 	/*
    197 	 * Add the specified key/data pair to the tree.  The R_IAFTER and
    198 	 * R_IBEFORE flags insert the key after/before the specified key.
    199 	 *
    200 	 * Pages are split as required.
    201 	 */
    202 	switch (flags) {
    203 	case R_IAFTER:
    204 		++index;
    205 		break;
    206 	case R_IBEFORE:
    207 		break;
    208 	default:
    209 		if (nrec < t->bt_nrecs &&
    210 		    __rec_dleaf(t, h, index) == RET_ERROR) {
    211 			mpool_put(t->bt_mp, h, 0);
    212 			return (RET_ERROR);
    213 		}
    214 		break;
    215 	}
    216 
    217 	/*
    218 	 * If not enough room, split the page.  The split code will insert
    219 	 * the key and data and unpin the current page.  If inserting into
    220 	 * the offset array, shift the pointers up.
    221 	 */
    222 	nbytes = NRLEAFDBT(data->size);
    223 	if (h->upper - h->lower < nbytes + sizeof(indx_t)) {
    224 		status = __bt_split(t, h, NULL, data, dflags, nbytes, index);
    225 		if (status == RET_SUCCESS)
    226 			++t->bt_nrecs;
    227 		return (status);
    228 	}
    229 
    230 	if (index < (nxtindex = NEXTINDEX(h)))
    231 		memmove(h->linp + index + 1, h->linp + index,
    232 		    (nxtindex - index) * sizeof(indx_t));
    233 	h->lower += sizeof(indx_t);
    234 
    235 	h->linp[index] = h->upper -= nbytes;
    236 	dest = (char *)h + h->upper;
    237 	WR_RLEAF(dest, data, dflags);
    238 
    239 	++t->bt_nrecs;
    240 	SET(t, B_MODIFIED);
    241 	mpool_put(t->bt_mp, h, MPOOL_DIRTY);
    242 
    243 	return (RET_SUCCESS);
    244 }
    245