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 * The node_t structure is for internal use only, lint doesn't grok it. 8 * 9 * Written by reading the System V Interface Definition, not the code. 10 * 11 * Totally public domain. 12 */ 13 14 #include <sys/cdefs.h> 15 #if 0 16 #if defined(LIBC_SCCS) && !defined(lint) 17 __RCSID("$NetBSD: twalk.c,v 1.4 2012/03/20 16:38:45 matt Exp $"); 18 #endif /* LIBC_SCCS and not lint */ 19 #endif 20 __FBSDID("$FreeBSD$"); 21 22 #define _SEARCH_PRIVATE 23 #include <search.h> 24 #include <stdlib.h> 25 26 typedef void (*cmp_fn_t)(const void *, VISIT, int); 27 28 /* Walk the nodes of a tree */ 29 static void 30 trecurse(const node_t *root, /* Root of the tree to be walked */ 31 cmp_fn_t action, 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(const void *vroot, cmp_fn_t action) /* Root of the tree to be walked */ 50 { 51 if (vroot != NULL && action != NULL) 52 trecurse(vroot, action, 0); 53 } 54