/* gdbmfetch.c - Find a key and return the associated data.  */

/*  This file is part of GDBM, the GNU data base manager, by Philip A. Nelson.
    Copyright (C) 1990  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 1, 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 author by:
       e-mail:  phil@wwu.edu
      us-mail:  Philip A. Nelson
                Computer Science Department
                Western Washington University
                Bellingham, WA 98226
        phone:  (206) 676-3035
       
*************************************************************************/

/*
 * MS-DOS port (c) 1990 by Thorsten Ohl, ohl@gnu.ai.mit.edu
 *
 * To this port, the same copying conditions apply as to the
 * original release.
 *
 * IMPORTANT:
 * This file is not identical to the original GNU release!
 * You should have received this code as patch to the official
 * GNU release.
 *
 * MORE IMPORTANT:
 * This port comes with ABSOLUTELY NO WARRANTY.
 *
 * $Header: e:/gnu/gdbm/RCS/gdbmfetc.c'v 1.4.0.1 90/08/16 09:22:27 tho Exp $
 */

#include <stdio.h>
#include <sys/types.h>
#ifndef MSDOS
#include <sys/file.h>
#endif /* not MSDOS */
#include <sys/stat.h>
#include "gdbmdefs.h"
#include "systems.h"
#include "gdbmerrno.h"
extern gdbm_error gdbm_errno;

/* Look up a given KEY and return the information associated with that KEY.
   The pointer in the structure that is  returned is a pointer to dynamically
   allocated memory block.  */

datum
gdbm_fetch (dbf, key)
     gdbm_file_info *dbf;
     datum key;
{
  datum  return_val;		/* The return value. */
  int    elem_loc;		/* The location in the bucket. */
  char  *find_data;		/* Returned from find_key. */
  LONG	 hash_val;		/* Returned from find_key. */

  /* Set the default return value. */
  return_val.dptr = NULL;

  /* Find the key and return a pointer to the data. */
  elem_loc = _gdbm_findkey (dbf, key, &find_data, &hash_val);

  /* Copy the data if the key was found.  */
  if (elem_loc >= 0)
    {
      /* This is the item.  Return the associated data. */
      return_val.dsize = dbf->bucket->h_table[elem_loc].data_size;
      return_val.dptr = (char *) malloc (return_val.dsize);
      if (return_val.dptr == NULL) _gdbm_fatal (dbf, "malloc error");
      bcopy (find_data, return_val.dptr, return_val.dsize);
    }

  /* Check for an error and return. */
  if (return_val.dptr == NULL) gdbm_errno = GDBM_ITEM_NOT_FOUND;
  return return_val;
}


