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/* |
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** Copyright (C) 2003 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: rt_move.c,v 1.1 2003/06/28 18:48:21 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: rt_move.c,v 1.1 2003/06/28 18:48:21 klmitch Exp $"); |
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|
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/** \ingroup dbprim_rbtree |
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* \brief Move a node in a red-black tree. |
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* |
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* This function moves an existing node in the red-black tree to |
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* correspond to the new key. |
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* |
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* \param tree A pointer to a #rb_tree_t. |
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* \param node A pointer to a #rb_node_t to be moved. It must |
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* already be in the red-black tree. |
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* \param key A pointer to a #db_key_t describing the new key for |
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* the node. |
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* |
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* \retval DB_ERR_BADARGS An invalid argument was given. |
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* \retval DB_ERR_UNUSED Node is not in a red-black tree. |
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* \retval DB_ERR_WRONGTABLE Node is not in this tree. |
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* \retval DB_ERR_FROZEN Red-black tree is frozen. |
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* \retval DB_ERR_DUPLICATE New key is a duplicate of an existing |
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* key. |
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* \retval DB_ERR_READDFAILED Unable to re-add node to tree. |
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*/ |
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unsigned long |
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rt_move(rb_tree_t *tree, rb_node_t *node, db_key_t *key) |
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{ |
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unsigned long retval; |
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|
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initialize_dbpr_error_table(); /* initialize error table */ |
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|
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if (!rt_verify(tree) || !rn_verify(node) || !key) /* verify arguments */ |
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return DB_ERR_BADARGS; |
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|
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if (!node->rn_tree) /* it's not in a tree */ |
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return DB_ERR_UNUSED; |
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if (node->rn_tree != tree) /* it's in the wrong tree */ |
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return DB_ERR_WRONGTABLE; |
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|
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if (tree->rt_flags & RBT_FLAG_FREEZE) /* don't mess with frozen trees */ |
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return DB_ERR_FROZEN; |
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|
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if (_rb_locate(tree, 0, key)) /* don't permit duplicates */ |
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return DB_ERR_DUPLICATE; |
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|
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/* OK, remove node from the tree... */ |
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if ((retval = rt_remove(tree, node))) |
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return retval; |
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|
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/* Now re-add it to the tree... */ |
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return rt_add(tree, node, key) ? DB_ERR_READDFAILED : 0; |
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} |
