1/* dbmseq.c - Visit all elements in the database.  This is the NDBM
2   interface. */
3
4/*  This file is part of GDBM, the GNU data base manager, by Philip A. Nelson.
5    Copyright (C) 1990, 1991, 1993  Free Software Foundation, Inc.
6
7    GDBM is free software; you can redistribute it and/or modify
8    it under the terms of the GNU General Public License as published by
9    the Free Software Foundation; either version 2, or (at your option)
10    any later version.
11
12    GDBM is distributed in the hope that it will be useful,
13    but WITHOUT ANY WARRANTY; without even the implied warranty of
14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15    GNU General Public License for more details.
16
17    You should have received a copy of the GNU General Public License
18    along with GDBM; see the file COPYING.  If not, write to
19    the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
20
21    You may contact the author by:
22       e-mail:  phil@cs.wwu.edu
23      us-mail:  Philip A. Nelson
24                Computer Science Department
25                Western Washington University
26                Bellingham, WA 98226
27
28*************************************************************************/
29
30
31/* include system configuration before all else. */
32#include "autoconf.h"
33
34#include "gdbmdefs.h"
35#include "extern.h"
36
37
38/* NDBM Start the visit of all keys in the database.  This produces
39   something in hash order, not in any sorted order.  DBF is the dbm file
40   information pointer. */
41
42datum
43dbm_firstkey (dbf)
44     gdbm_file_info *dbf;
45{
46  datum ret_val;
47
48  /* Free previous dynamic memory, do actual call, and save pointer to new
49     memory. */
50  ret_val = gdbm_firstkey (dbf);
51  if (_gdbm_memory.dptr != NULL) free (_gdbm_memory.dptr);
52  _gdbm_memory = ret_val;
53
54  /* Return the new value. */
55  return ret_val;
56}
57
58
59/* NDBM Continue visiting all keys.  The next key in the sequence is returned.
60   DBF is the file information pointer. */
61
62datum
63dbm_nextkey (dbf)
64     gdbm_file_info *dbf;
65{
66  datum ret_val;
67
68  /* Make sure we have a valid key. */
69  if (_gdbm_memory.dptr == NULL)
70    return _gdbm_memory;
71
72  /* Call gdbm nextkey with the old value. After that, free the old value. */
73  ret_val = gdbm_nextkey (dbf,_gdbm_memory);
74  if (_gdbm_memory.dptr != NULL) free (_gdbm_memory.dptr);
75  _gdbm_memory = ret_val;
76
77  /* Return the new value. */
78  return ret_val;
79}
80
81