1 /* $NetBSD: twalk.c,v 1.4 2012/03/20 16:38:45 matt Exp $ */ 2 3 /* 4 * Tree search generalized from Knuth (6.2.2) Algorithm T just like 5 * the AT&T man page says. 6 * 7 * Written by reading the System V Interface Definition, not the code. 8 * 9 * Totally public domain. 10 */ 11 12 #include <sys/cdefs.h> 13 #if 0 14 #if defined(LIBC_SCCS) && !defined(lint) 15 __RCSID("$NetBSD: twalk.c,v 1.4 2012/03/20 16:38:45 matt Exp $"); 16 #endif /* LIBC_SCCS and not lint */ 17 #endif 18 #define _SEARCH_PRIVATE 19 #include <search.h> 20 #include <stdlib.h> 21 22 typedef void (*cmp_fn_t)(const posix_tnode *, VISIT, int); 23 24 /* Walk the nodes of a tree */ 25 static void 26 trecurse(const posix_tnode *root, cmp_fn_t action, int level) 27 { 28 29 if (root->llink == NULL && root->rlink == NULL) 30 (*action)(root, leaf, level); 31 else { 32 (*action)(root, preorder, level); 33 if (root->llink != NULL) 34 trecurse(root->llink, action, level + 1); 35 (*action)(root, postorder, level); 36 if (root->rlink != NULL) 37 trecurse(root->rlink, action, level + 1); 38 (*action)(root, endorder, level); 39 } 40 } 41 42 /* Walk the nodes of a tree */ 43 void 44 twalk(const posix_tnode *vroot, cmp_fn_t action) 45 { 46 if (vroot != NULL && action != NULL) 47 trecurse(vroot, action, 0); 48 } 49