1 /* 2 * Tree search generalized from Knuth (6.2.2) Algorithm T just like 3 * the AT&T man page says. 4 * 5 * The node_t structure is for internal use only, lint doesn't grok it. 6 * 7 * Written by reading the System V Interface Definition, not the code. 8 * 9 * Totally public domain. 10 * 11 * $NetBSD: twalk.c,v 1.1 1999/02/22 10:33:16 christos Exp $ 12 * $FreeBSD: src/lib/libc/stdlib/twalk.c,v 1.1.2.1 2000/08/17 07:38:39 jhb Exp $ 13 * $DragonFly: src/lib/libc/stdlib/twalk.c,v 1.5 2005/11/24 17:18:30 swildner Exp $ 14 */ 15 16 #include <sys/cdefs.h> 17 18 #include <assert.h> 19 #define _SEARCH_PRIVATE 20 #include <search.h> 21 #include <stdlib.h> 22 23 static void trecurse (const node_t *, 24 void (*action)(const void *, VISIT, int), int level); 25 26 /* Walk the nodes of a tree 27 * 28 * Parameters: 29 * root: Root of the tree to be walked 30 */ 31 static void 32 trecurse(const node_t *root, void (*action)(const void *, VISIT, int), 33 int level) 34 { 35 36 if (root->llink == NULL && root->rlink == NULL) 37 (*action)(root, leaf, level); 38 else { 39 (*action)(root, preorder, level); 40 if (root->llink != NULL) 41 trecurse(root->llink, action, level + 1); 42 (*action)(root, postorder, level); 43 if (root->rlink != NULL) 44 trecurse(root->rlink, action, level + 1); 45 (*action)(root, endorder, level); 46 } 47 } 48 49 /* Walk the nodes of a tree 50 * 51 * Parameters: 52 * vroot: Root of the tree to be walked 53 */ 54 void 55 twalk(const void *vroot, 56 void (*action)(const void *, VISIT, int)) 57 { 58 if (vroot != NULL && action != NULL) 59 trecurse(vroot, action, 0); 60 } 61