/* gdbmsetopt.c - set options pertaining to a GDBM descriptor. */

/*  This file is part of GDBM, the GNU data base manager, by Philip A. Nelson.
    Copyright (C) 1993, 1994  Free Software Foundation, Inc.

    GDBM is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2, or (at your option)
    any later version.

    GDBM is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with GDBM; see the file COPYING.  If not, write to
    the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.

    You may contact the original author by:
       e-mail:  phil@cs.wwu.edu
      us-mail:  Philip A. Nelson
                Computer Science Department
                Western Washington University
                Bellingham, WA 98226

    The author of this file is:
       e-mail:  downsj@downsj.com

*************************************************************************/



#include "gdbmdefs.h"
#include "gdbmerrno.h"

/* operate on an already open descriptor. */

/* ARGSUSED */
int gdbm_setopt (
    gdbm_file_info *dbf,            /* descriptor to operate on. */
    int optflag,                    /* option to set. */
    int *optval,                    /* pointer to option value. */
    int optlen)                     /* size of optval. */
{
  switch (optflag) {
  case GDBM_CACHESIZE:
    /* Optval will point to the new size of the cache. */
    if (dbf->bucket_cache != NULL) {
      gdbm_errno = GDBM_OPT_ALREADY_SET;
      return (-1);
    }

    return (_gdbm_init_cache (dbf, ((*optval) > 9) ? (*optval) : 10));

  case GDBM_FASTMODE:
    /* Obsolete form of SYNCMODE. */
    if ((*optval != TRUE) && (*optval != FALSE)) {
      gdbm_errno = GDBM_OPT_ILLEGAL;
      return (-1);
    }

    dbf->fast_write = *optval;
    break;

  case GDBM_SYNCMODE:
    /* Optval will point to either true or false. */
    if ((*optval != TRUE) && (*optval != FALSE)) {
      gdbm_errno = GDBM_OPT_ILLEGAL;
      return (-1);
    }

    dbf->fast_write = !(*optval);
    break;

  case GDBM_CENTFREE:
    /* Optval will point to either true or false. */
    if ((*optval != TRUE) && (*optval != FALSE)) {
      gdbm_errno = GDBM_OPT_ILLEGAL;
      return (-1);
    }

    dbf->fast_write = *optval;
    break;

  case GDBM_COALESCEBLKS:
    /* Optval will point to either true or false. */
    if ((*optval != TRUE) && (*optval != FALSE)) {
      gdbm_errno = GDBM_OPT_ILLEGAL;
      return (-1);
    }

    dbf->fast_write = *optval;
    break;

  default:
    gdbm_errno = GDBM_OPT_ILLEGAL;
    return (-1);
  }

  return (0);
}