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/* |
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** Copyright (C) 2002 by Kevin L. Mitchell <klmitch@mit.edu> |
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** |
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** This library is free software; you can redistribute it and/or |
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** modify it under the terms of the GNU Library General Public |
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** License as published by the Free Software Foundation; either |
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** version 2 of the License, or (at your option) any later version. |
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** |
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** This library is distributed in the hope that it will be useful, |
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** but WITHOUT ANY WARRANTY; without even the implied warranty of |
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** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
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** Library General Public License for more details. |
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** |
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** You should have received a copy of the GNU Library General Public |
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** License along with this library; if not, write to the Free |
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** Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, |
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** MA 02111-1307, USA |
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** |
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** @(#)$Id: ht_iter.c,v 1.2 2003/06/12 01:10:04 klmitch Exp $ |
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*/ |
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#include "dbprim.h" |
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#include "dbprim_int.h" |
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|
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RCSTAG("@(#)$Id: ht_iter.c,v 1.2 2003/06/12 01:10:04 klmitch Exp $"); |
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|
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/** \ingroup dbprim_hash |
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* \brief Iterate over each entry in a hash table. |
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* |
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* This function iterates over every entry in a hash table (in an |
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* unspecified order), executing the given \p iter_func on each entry. |
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* |
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* \param table A pointer to a #hash_table_t. |
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* \param iter_func |
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* A pointer to a callback function used to perform |
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* user-specified actions on an entry in a hash table. \c |
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* NULL is an invalid value. See the documentation for |
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* #hash_iter_t for more information. |
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* \param extra A \c void pointer that will be passed to \p |
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* iter_func. |
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* |
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* \retval DB_ERR_BADARGS An argument was invalid. |
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* \retval DB_ERR_FROZEN The hash table is frozen. |
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*/ |
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unsigned long |
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ht_iter(hash_table_t *table, hash_iter_t iter_func, void *extra) |
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{ |
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unsigned long retval; |
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int i; |
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link_elem_t *elem; |
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|
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initialize_dbpr_error_table(); /* initialize error table */ |
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|
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if (!ht_verify(table) || !iter_func) /* verify arguments */ |
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return DB_ERR_BADARGS; |
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|
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if (table->ht_flags & HASH_FLAG_FREEZE) /* don't mess with frozen tables */ |
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return DB_ERR_FROZEN; |
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|
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table->ht_flags |= HASH_FLAG_FREEZE; /* freeze the table */ |
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|
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/* walk through all the elements and call the iteration function */ |
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for (i = 0; i < table->ht_modulus; i++) |
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for (elem = ll_first(&table->ht_table[i]); elem; elem = le_next(elem)) |
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if ((retval = (*iter_func)(table, le_object(elem), extra))) { |
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table->ht_flags &= ~HASH_FLAG_FREEZE; /* unfreeze the table */ |
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return retval; |
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} |
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|
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table->ht_flags &= ~HASH_FLAG_FREEZE; /* unfreeze the table */ |
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|
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return 0; |
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} |
