1/* Binary tree data structure. 2 Copyright (C) 2006 Free Software Foundation, Inc. 3 4 This program is free software; you can redistribute it and/or modify it 5 under the terms of the GNU Library General Public License as published 6 by the Free Software Foundation; either version 2, or (at your option) 7 any later version. 8 9 This program is distributed in the hope that it will be useful, 10 but WITHOUT ANY WARRANTY; without even the implied warranty of 11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 12 Library General Public License for more details. 13 14 You should have received a copy of the GNU Library General Public 15 License along with this program; if not, write to the Free Software 16 Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, 17 USA. */ 18 19#ifndef _TSEARCH_H 20#define _TSEARCH_H 21 22#if HAVE_TSEARCH 23 24/* Get tseach(), tfind(), tdelete(), twalk() declarations. */ 25#include <search.h> 26 27#else 28 29#ifdef __cplusplus 30extern "C" { 31#endif 32 33/* See <http://www.opengroup.org/susv3xbd/search.h.html>, 34 <http://www.opengroup.org/susv3xsh/tsearch.html> 35 for details. */ 36 37typedef enum 38{ 39 preorder, 40 postorder, 41 endorder, 42 leaf 43} 44VISIT; 45 46/* Searches an element in the tree *VROOTP that compares equal to KEY. 47 If one is found, it is returned. Otherwise, a new element equal to KEY 48 is inserted in the tree and is returned. */ 49extern void * tsearch (const void *key, void **vrootp, 50 int (*compar) (const void *, const void *)); 51 52/* Searches an element in the tree *VROOTP that compares equal to KEY. 53 If one is found, it is returned. Otherwise, NULL is returned. */ 54extern void * tfind (const void *key, void *const *vrootp, 55 int (*compar) (const void *, const void *)); 56 57/* Searches an element in the tree *VROOTP that compares equal to KEY. 58 If one is found, it is removed from the tree, and its parent node is 59 returned. Otherwise, NULL is returned. */ 60extern void * tdelete (const void *key, void **vrootp, 61 int (*compar) (const void *, const void *)); 62 63/* Perform a depth-first, left-to-right traversal of the tree VROOT. 64 The ACTION function is called: 65 - for non-leaf nodes: 3 times, before the left subtree traversal, 66 after the left subtree traversal but before the right subtree traversal, 67 and after the right subtree traversal, 68 - for leaf nodes: once. 69 The arguments passed to ACTION are: 70 1. the node; it can be casted to a 'const void * const *', i.e. into a 71 pointer to the key, 72 2. an indicator which visit of the node this is, 73 3. the level of the node in the tree (0 for the root). */ 74extern void twalk (const void *vroot, 75 void (*action) (const void *, VISIT, int)); 76 77#ifdef __cplusplus 78} 79#endif 80 81#endif 82 83#endif /* _TSEARCH_H */ 84