/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */

/*
 * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*      Copyright (c) 1988 AT&T */
/*        All Rights Reserved   */

/*
 * rmdirp() removes directories in path "d". Removal starts from the
 * right most directory in the path and goes backward as far as possible.
 * The remaining path, which is not removed for some reason, is stored in "d1".
 * If nothing remains, "d1" is empty.
 *
 * rmdirp()
 * returns 0 only if it succeeds in removing every directory in d.
 * returns -1 if removal stops because of errors other than the following.
 * returns -2 if removal stops when "." or ".." is encountered in path.
 * returns -3 if removal stops because it's the current directory.
 */

#include <sys/types.h>
#include <libgen.h>
#include <sys/stat.h>
#include <string.h>
#include <unistd.h>

static int dotdot(char *);

int
rmdirp(char *d, char *d1)
{
        struct stat64   st, cst;
        int             currstat;
        char            *slash;

        slash = strrchr(d, '/');
        currstat = stat64(".", &cst);

        /* Starts from right most element */

        while (d) {
                /* If it's under current directory */

                if (slash == NULL) {
                        /* Stop if it's . or .. */

                        if (dotdot(d)) {
                                (void) strcpy(d1, d);
                                return (-2);
                        }
                        /* Stop if can not stat it */

                } else {        /* If there's a slash before it */

                        /* If extra / in the end */
                        if (slash != d) {
                                if (++slash == strrchr(d, '\0')) {
                                        *(--slash) = '\0';
                                        slash = strrchr(d, '/');
                                        continue;
                                } else {
                                        slash--;
                                }
                        }

                        /* Stop if it's . or .. */

                        if (dotdot(++slash)) {
                                (void) strcpy(d1, d);
                                return (-2);
                        }
                        slash--;

                        /* Stop if can not stat it */

                        if (stat64(d, &st) < 0) {
                                (void) strcpy(d1, d);
                                return (-1);
                        }
                        if (currstat == 0) {
                                /* Stop if it's current directory */
                                if ((st.st_ino == cst.st_ino) &&
                                    (st.st_dev == cst.st_dev)) {
                                        (void) strcpy(d1, d);
                                        return (-3);
                                }
                        }
                } /* End of else */


                /* Remove it */
                if (rmdir(d) != 0) {
                        (void) strcpy(d1, d);
                        return (-1);
                }

                /* Have reached left end, break */

                if (slash == NULL || slash == d)
                        break;

                /* Go backward to next directory */
                *slash = '\0';
                slash = strrchr(d, '/');
        }
        *d1 = '\0';
        return (0);
}


static int
dotdot(char *dir)
{
        if (strcmp(dir, ".") == 0 || strcmp(dir, "..") == 0)
                return (-1);
        return (0);
}