| [15371] | 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: phil@cs.wwu.edu |
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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 | /* include system configuration before all else. */ |
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| 31 | #include "autoconf.h" |
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| 32 | |
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| 33 | #include "gdbmdefs.h" |
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| 34 | #include "gdbmerrno.h" |
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| 35 | |
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| 36 | /* Look up a given KEY and return the information associated with that KEY. |
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| 37 | The pointer in the structure that is returned is a pointer to dynamically |
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| 38 | allocated memory block. */ |
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| 39 | |
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| 40 | datum |
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| 41 | gdbm_fetch (dbf, key) |
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| 42 | gdbm_file_info *dbf; |
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| 43 | datum key; |
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| 44 | { |
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| 45 | datum return_val; /* The return value. */ |
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| 46 | int elem_loc; /* The location in the bucket. */ |
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| 47 | char *find_data; /* Returned from find_key. */ |
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| 48 | int hash_val; /* Returned from find_key. */ |
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| 49 | |
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| 50 | /* Set the default return value. */ |
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| 51 | return_val.dptr = NULL; |
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| 52 | return_val.dsize = 0; |
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| 53 | |
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| 54 | /* Initialize the gdbm_errno variable. */ |
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| 55 | gdbm_errno = GDBM_NO_ERROR; |
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| 56 | |
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| 57 | /* Find the key and return a pointer to the data. */ |
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| 58 | elem_loc = _gdbm_findkey (dbf, key, &find_data, &hash_val); |
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| 59 | |
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| 60 | /* Copy the data if the key was found. */ |
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| 61 | if (elem_loc >= 0) |
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| 62 | { |
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| 63 | /* This is the item. Return the associated data. */ |
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| 64 | return_val.dsize = dbf->bucket->h_table[elem_loc].data_size; |
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| 65 | if (return_val.dsize == 0) |
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| 66 | return_val.dptr = (char *) malloc (1); |
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| 67 | else |
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| 68 | return_val.dptr = (char *) malloc (return_val.dsize); |
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| 69 | if (return_val.dptr == NULL) _gdbm_fatal (dbf, "malloc error"); |
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| 70 | bcopy (find_data, return_val.dptr, return_val.dsize); |
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| 71 | } |
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| 72 | |
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| 73 | /* Check for an error and return. */ |
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| 74 | if (return_val.dptr == NULL) gdbm_errno = GDBM_ITEM_NOT_FOUND; |
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| 75 | return return_val; |
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| 76 | } |
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