/* $Id: tree.c,v 2.1 2005/10/09 03:52:38 ksb Exp $
 */
#include <sys/param.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include "machine.h"
#include "tree.h"

static TREE *pThead = NULL;

static TREE *
pTnewNode(pcName)
char *pcName;
{
	register TREE *pTnew;

	pTnew = (TREE *) malloc(sizeof(TREE));
	pTnew->pcName = pcName ? strdup(pcName) : NULL;
	pTnew->pTparent = NULL;
	pTnew->pTsib = NULL;
	pTnew->pTchild = NULL;
	pTnew->fMark = 0;

	return pTnew;
}

static TREE *
pTaddChild(pTnode, pcName)
TREE *pTnode;
char *pcName;
{
	register TREE *pTnew = pTnewNode(pcName);

	pTnew->pTparent = pTnode;
	pTnew->pTsib = pTnode->pTchild;
	pTnode->pTchild = pTnew;

	return pTnew;
}

static TREE *
pTfindChild(pTnode, pcName)
TREE *pTnode;
char *pcName;
{
	for (pTnode = pTnode->pTchild; pTnode; pTnode = pTnode->pTsib) {
		if (!strcmp(pcName, pTnode->pcName))
			return pTnode;
	}
	return NULL;
}

/* generate the elements of the path in the current filename
 * in our representation of the directory tree.
 */
TREE *
pTfindDirTree(pcName)
char *pcName;
{
	register char *s = pcName, *t;
	register TREE *pTnode, *pTnext;

	if (!pThead) {
		/* initialize */
		pThead = pTnewNode(NULL);
	}

	if (0 == strncmp(s, "./", 2)) s += 2;

	pTnode = pThead;
	for (;;) {
		t = strchr(s, '/');
		if (!t) {
			return pTnode;
		}

		*t = '\000';
		if ((TREE *)0 == (pTnext = pTfindChild(pTnode, s)))
			pTnode = pTaddChild(pTnode, s);
		else
			pTnode = pTnext;
		*t = '/';
		s = t + 1;
	}
	/* NOT REACHED */
}

/* mark all the elements of the path you found with pTfindDirTree
 */
void
MarkDirTree(pTnode)
TREE *pTnode;
{
	for (; pTnode; pTnode = pTnode->pTparent)
		pTnode->fMark = 1;
}

/* do something with all the elements you marked with MarkDirTree.
 * I did this in a tricky nonrecursive way first, but it wasn't really
 * better than the recursion.
 */
static void
_UseDirMarks(CFunc, pTnode, pcPath)
void (*CFunc)();
TREE *pTnode;
char *pcPath;
{
	char acBuf[MAXPATHLEN+1];
	TREE *pTloop;

	if ((TREE *)0 == pTnode || !pTnode->fMark) {
		return;
	}

	/* do self then children (preorder traversal) */
	if (pTnode->pcName) {
		sprintf(acBuf, "%s%s", pcPath, pTnode->pcName);
		(*CFunc)(acBuf);
		strcat(acBuf, "/");
	} else {
		acBuf[0] = '\000';
	}
	for (pTloop = pTnode->pTchild; pTloop; pTloop = pTloop->pTsib) {
		_UseDirMarks(CFunc, pTloop, acBuf);
	}
}

void
UseDirMarks(CFunc)
void (*CFunc)();
{
	_UseDirMarks(CFunc, pThead, "");
}

#ifdef TEST
extern puts();

main(ac, av)
int ac;
char **av;
{
	while (*av) {
		MarkDirTree(pTfindDirTree(*av));
		av++;
	}
	UseDirMarks(puts);
}
#endif