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