source: trunk/libs/newlib/src/newlib/libc/search/twalk.c @ 471

/*      $NetBSD: twalk.c,v 1.1 1999/02/22 10:33:16 christos Exp $       */

/*
 * Tree search generalized from Knuth (6.2.2) Algorithm T just like
 * the AT&T man page says.
 *
 * The node_t structure is for internal use only, lint doesn't grok it.
 *
 * Written by reading the System V Interface Definition, not the code.
 *
 * Totally public domain.
 */

#include <sys/cdefs.h>
#if 0
#if defined(LIBC_SCCS) && !defined(lint)
__RCSID("$NetBSD: twalk.c,v 1.1 1999/02/22 10:33:16 christos Exp $");
#endif /* LIBC_SCCS and not lint */
#endif

#include <assert.h>
#define _SEARCH_PRIVATE
#include <search.h>
#include <stdlib.h>

static void trecurse(const node_t *,
    void (*action)(const void *, VISIT, int), int level);

/* Walk the nodes of a tree */
static void
trecurse(root, action, level)
        const node_t *root;     /* Root of the tree to be walked */
        void (*action)(const void *, VISIT, int);
        int level;
{

        if (root->llink == NULL && root->rlink == NULL)
                (*action)(root, leaf, level);
        else {
                (*action)(root, preorder, level);
                if (root->llink != NULL)
                        trecurse(root->llink, action, level + 1);
                (*action)(root, postorder, level);
                if (root->rlink != NULL)
                        trecurse(root->rlink, action, level + 1);
                (*action)(root, endorder, level);
        }
}

/* Walk the nodes of a tree */
void
twalk (const void *vroot,       /* Root of the tree to be walked */
        void (*action)(const void *, VISIT, int))
{
        if (vroot != NULL && action != NULL)
                trecurse(vroot, action, 0);
}