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