| 1 | /* gdbmfetch.c - Find a key and return the associated data. */
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| 2 |
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| 3 | /* This file is part of GDBM, the GNU data base manager, by Philip A. Nelson.
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| 4 | Copyright (C) 1990, 1991, 1993 Free Software Foundation, Inc.
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| 5 |
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| 6 | GDBM is free software; you can redistribute it and/or modify
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| 7 | it under the terms of the GNU General Public License as published by
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| 8 | the Free Software Foundation; either version 2, or (at your option)
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| 9 | any later version.
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| 10 |
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| 11 | GDBM is distributed in the hope that it will be useful,
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| 12 | but WITHOUT ANY WARRANTY; without even the implied warranty of
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| 13 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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| 14 | GNU General Public License for more details.
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| 15 |
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| 16 | You should have received a copy of the GNU General Public License
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| 17 | along with GDBM; see the file COPYING. If not, write to
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| 18 | the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
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| 19 |
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| 20 | You may contact the author by:
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| 21 | e-mail: [email protected]
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| 22 | us-mail: Philip A. Nelson
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| 23 | Computer Science Department
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| 24 | Western Washington University
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| 25 | Bellingham, WA 98226
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| 26 |
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| 27 | *************************************************************************/
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| 28 |
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| 29 |
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| 30 | /* AIX demands this be the very first thing in the file. */
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| 31 | #if !defined(__GNUC__) && defined(_AIX)
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| 32 | #pragma alloca
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| 33 | #endif
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| 34 |
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| 35 | /* include system configuration before all else. */
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| 36 | #include "autoconf.h"
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| 37 |
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| 38 | #include "gdbmdefs.h"
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| 39 | #include "gdbmerrno.h"
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| 40 |
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| 41 | /* Look up a given KEY and return the information associated with that KEY.
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| 42 | The pointer in the structure that is returned is a pointer to dynamically
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| 43 | allocated memory block. */
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| 44 |
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| 45 | datum
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| 46 | gdbm_fetch (dbf, key)
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| 47 | gdbm_file_info *dbf;
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| 48 | datum key;
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| 49 | {
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| 50 | datum return_val; /* The return value. */
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| 51 | int elem_loc; /* The location in the bucket. */
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| 52 | char *find_data; /* Returned from find_key. */
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| 53 | word_t hash_val; /* Returned from find_key. */
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| 54 |
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| 55 | /* Set the default return value. */
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| 56 | return_val.dptr = NULL;
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| 57 | return_val.dsize = 0;
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| 58 |
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| 59 | /* Initialize the gdbm_errno variable. */
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| 60 | gdbm_errno = GDBM_NO_ERROR;
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| 61 |
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| 62 | /* Find the key and return a pointer to the data. */
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| 63 | elem_loc = _gdbm_findkey (dbf, key, &find_data, &hash_val);
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| 64 |
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| 65 | /* Copy the data if the key was found. */
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| 66 | if (elem_loc >= 0)
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| 67 | {
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| 68 | /* This is the item. Return the associated data. */
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| 69 | return_val.dsize = dbf->bucket->h_table[elem_loc].data_size;
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| 70 | if (return_val.dsize == 0)
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| 71 | return_val.dptr = (char *) malloc (1);
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| 72 | else
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| 73 | return_val.dptr = (char *) malloc (return_val.dsize);
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| 74 | if (return_val.dptr == NULL) _gdbm_fatal (dbf, "malloc error");
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| 75 | bcopy (find_data, return_val.dptr, return_val.dsize);
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| 76 | }
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| 77 |
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| 78 | /* Check for an error and return. */
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| 79 | if (return_val.dptr == NULL) gdbm_errno = GDBM_ITEM_NOT_FOUND;
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| 80 | return return_val;
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| 81 | }
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