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);
}