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 1.3 2003/09/06 08:19:16 asmodai 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 static void 28 trecurse(root, action, level) 29 const node_t *root; /* Root of the tree to be walked */ 30 void (*action) (const void *, VISIT, int); 31 int level; 32 { 33 34 if (root->llink == NULL && root->rlink == NULL) 35 (*action)(root, leaf, level); 36 else { 37 (*action)(root, preorder, level); 38 if (root->llink != NULL) 39 trecurse(root->llink, action, level + 1); 40 (*action)(root, postorder, level); 41 if (root->rlink != NULL) 42 trecurse(root->rlink, action, level + 1); 43 (*action)(root, endorder, level); 44 } 45 } 46 47 /* Walk the nodes of a tree */ 48 void 49 twalk(vroot, action) 50 const void *vroot; /* Root of the tree to be walked */ 51 void (*action) (const void *, VISIT, int); 52 { 53 if (vroot != NULL && action != NULL) 54 trecurse(vroot, action, 0); 55 } 56