rec_put.c

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/*-
 * Copyright (c) 1990, 1993, 1994
 *  The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *  This product includes software developed by the University of
 *  California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */
 
#if defined(LIBC_SCCS) && !defined(lint)
static char sccsid[] = "@(#)rec_put.c   8.7 (Berkeley) 8/18/94";
#endif /* LIBC_SCCS and not lint */
 
#include <sys/types.h>
 
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
 
#include "../include/db.h"
#include "recno.h"
 
/*
 * __REC_PUT -- Add a recno item to the tree.
 *
 * Parameters:
 *  dbp:    pointer to access method
 *  key:    key
 *  data:   data
 *  flag:   R_CURSOR, R_IAFTER, R_IBEFORE, R_NOOVERWRITE
 *
 * Returns:
 *  RET_ERROR, RET_SUCCESS and RET_SPECIAL if the key is
 *  already in the tree and R_NOOVERWRITE specified.
 */
int
__rec_put(dbp, key, data, flags)
    const DB *dbp;
    DBT *key;
    const DBT *data;
    u_int flags;
{
    BTREE *t;
    DBT fdata, tdata;
    recno_t nrec;
    int status;
 
    t = dbp->internal;
 
    /* Toss any page pinned across calls. */
    if (t->bt_pinned != NULL) {
        mpool_put(t->bt_mp, t->bt_pinned, 0);
        t->bt_pinned = NULL;
    }
 
    /*
     * If using fixed-length records, and the record is long, return
     * EINVAL.  If it's short, pad it out.  Use the record data return
     * memory, it's only short-term.
     */
    if (F_ISSET(t, R_FIXLEN) && data->size != t->bt_reclen) {
        if (data->size > t->bt_reclen)
            goto einval;
 
        if (t->bt_rdata.size < t->bt_reclen) {
            t->bt_rdata.data = t->bt_rdata.data == NULL ?
                malloc(t->bt_reclen) :
                realloc(t->bt_rdata.data, t->bt_reclen);
            if (t->bt_rdata.data == NULL)
                return (RET_ERROR);
            t->bt_rdata.size = t->bt_reclen;
        }
        memmove(t->bt_rdata.data, data->data, data->size);
        memset((char *)t->bt_rdata.data + data->size,
            t->bt_bval, t->bt_reclen - data->size);
        fdata.data = t->bt_rdata.data;
        fdata.size = t->bt_reclen;
    } else {
        fdata.data = data->data;
        fdata.size = data->size;
    }
 
    switch (flags) {
    case R_CURSOR:
        if (!F_ISSET(&t->bt_cursor, CURS_INIT))
            goto einval;
        nrec = t->bt_cursor.rcursor;
        break;
    case R_SETCURSOR:
        if ((nrec = *(recno_t *)key->data) == 0)
            goto einval;
        break;
    case R_IAFTER:
        if ((nrec = *(recno_t *)key->data) == 0) {
            nrec = 1;
            flags = R_IBEFORE;
        }
        break;
    case 0:
    case R_IBEFORE:
        if ((nrec = *(recno_t *)key->data) == 0)
            goto einval;
        break;
    case R_NOOVERWRITE:
        if ((nrec = *(recno_t *)key->data) == 0)
            goto einval;
        if (nrec <= t->bt_nrecs)
            return (RET_SPECIAL);
        break;
    default:
einval:     errno = EINVAL;
        return (RET_ERROR);
    }
 
    /*
     * Make sure that records up to and including the put record are
     * already in the database.  If skipping records, create empty ones.
     */
    if (nrec > t->bt_nrecs) {
        if (!F_ISSET(t, R_EOF | R_INMEM) &&
            t->bt_irec(t, nrec) == RET_ERROR)
            return (RET_ERROR);
        if (nrec > t->bt_nrecs + 1) {
            if (F_ISSET(t, R_FIXLEN)) {
                if ((tdata.data =
                    (void *)malloc(t->bt_reclen)) == NULL)
                    return (RET_ERROR);
                tdata.size = t->bt_reclen;
                memset(tdata.data, t->bt_bval, tdata.size);
            } else {
                tdata.data = NULL;
                tdata.size = 0;
            }
            while (nrec > t->bt_nrecs + 1)
                if (__rec_iput(t,
                    t->bt_nrecs, &tdata, 0) != RET_SUCCESS)
                    return (RET_ERROR);
            if (F_ISSET(t, R_FIXLEN))
                free(tdata.data);
        }
    }
 
    if ((status = __rec_iput(t, nrec - 1, &fdata, flags)) != RET_SUCCESS)
        return (status);
 
    if (flags == R_SETCURSOR)
        t->bt_cursor.rcursor = nrec;
 
    F_SET(t, R_MODIFIED);
    return (__rec_ret(t, NULL, nrec, key, NULL));
}
 
/*
 * __REC_IPUT -- Add a recno item to the tree.
 *
 * Parameters:
 *  t:  tree
 *  nrec:   record number
 *  data:   data
 *
 * Returns:
 *  RET_ERROR, RET_SUCCESS
 */
int
__rec_iput(t, nrec, data, flags)
    BTREE *t;
    recno_t nrec;
    const DBT *data;
    u_int flags;
{
    DBT tdata;
    EPG *e;
    PAGE *h;
    indx_t idx, nxtindex;
    pgno_t pg;
    u_int32_t nbytes;
    int dflags, status;
    char *dest, db[NOVFLSIZE];
 
    /*
     * If the data won't fit on a page, store it on indirect pages.
     *
     * XXX
     * If the insert fails later on, these pages aren't recovered.
     */
    if (data->size > t->bt_ovflsize) {
        if (__ovfl_put(t, data, &pg) == RET_ERROR)
            return (RET_ERROR);
        tdata.data = db;
        tdata.size = NOVFLSIZE;
        *(pgno_t *)db = pg;
        *(u_int32_t *)(db + sizeof(pgno_t)) = data->size;
        dflags = P_BIGDATA;
        data = &tdata;
    } else
        dflags = 0;
 
    /* __rec_search pins the returned page. */
    if ((e = __rec_search(t, nrec,
        nrec > t->bt_nrecs || flags == R_IAFTER || flags == R_IBEFORE ?
        SINSERT : SEARCH)) == NULL)
        return (RET_ERROR);
 
    h = e->page;
    idx = e->index;
 
    /*
     * Add the specified key/data pair to the tree.  The R_IAFTER and
     * R_IBEFORE flags insert the key after/before the specified key.
     *
     * Pages are split as required.
     */
    switch (flags) {
    case R_IAFTER:
        ++idx;
        break;
    case R_IBEFORE:
        break;
    default:
        if (nrec < t->bt_nrecs &&
            __rec_dleaf(t, h, idx) == RET_ERROR) {
            mpool_put(t->bt_mp, h, 0);
            return (RET_ERROR);
        }
        break;
    }
 
    /*
     * If not enough room, split the page.  The split code will insert
     * the key and data and unpin the current page.  If inserting into
     * the offset array, shift the pointers up.
     */
    nbytes = NRLEAFDBT(data->size);
    if ((u_int32_t) (h->upper - h->lower) < nbytes + sizeof(indx_t)) {
        status = __bt_split(t, h, NULL, data, dflags, nbytes, idx);
        if (status == RET_SUCCESS)
            ++t->bt_nrecs;
        return (status);
    }
 
    if (idx < (nxtindex = NEXTINDEX(h)))
        memmove(h->linp + idx + 1, h->linp + idx,
            (nxtindex - idx) * sizeof(indx_t));
    h->lower += sizeof(indx_t);
 
    h->linp[idx] = h->upper -= nbytes;
    dest = (char *)h + h->upper;
    WR_RLEAF(dest, data, dflags);
 
    ++t->bt_nrecs;
    F_SET(t, B_MODIFIED);
    mpool_put(t->bt_mp, h, MPOOL_DIRTY);
 
    return (RET_SUCCESS);
}