root/sbin/restore/utilities.c
/*-
 * SPDX-License-Identifier: BSD-3-Clause
 *
 * Copyright (c) 1983, 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#include <sys/param.h>
#include <sys/stat.h>

#include <ufs/ufs/dinode.h>
#include <ufs/ufs/dir.h>

#include <errno.h>
#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#include "restore.h"
#include "extern.h"

/*
 * Insure that all the components of a pathname exist.
 */
void
pathcheck(char *name)
{
        char *cp;
        struct entry *ep;
        char *start;

        start = strchr(name, '/');
        if (start == NULL)
                return;
        for (cp = start; *cp != '\0'; cp++) {
                if (*cp != '/')
                        continue;
                *cp = '\0';
                ep = lookupname(name);
                if (ep == NULL) {
                        /* Safe; we know the pathname exists in the dump. */
                        ep = addentry(name, pathsearch(name)->d_ino, NODE);
                        newnode(ep);
                }
                ep->e_flags |= NEW|KEEP;
                *cp = '/';
        }
}

/*
 * Change a name to a unique temporary name.
 */
void
mktempname(struct entry *ep)
{
        char oldname[MAXPATHLEN];

        if (ep->e_flags & TMPNAME)
                badentry(ep, "mktempname: called with TMPNAME");
        ep->e_flags |= TMPNAME;
        (void) strcpy(oldname, myname(ep));
        freename(ep->e_name);
        ep->e_name = savename(gentempname(ep));
        ep->e_namlen = strlen(ep->e_name);
        renameit(oldname, myname(ep));
}

/*
 * Generate a temporary name for an entry.
 */
char *
gentempname(struct entry *ep)
{
        static char name[MAXPATHLEN];
        struct entry *np;
        long i = 0;

        for (np = lookupino(ep->e_ino);
            np != NULL && np != ep; np = np->e_links)
                i++;
        if (np == NULL)
                badentry(ep, "not on ino list");
        (void) sprintf(name, "%s%ld%lu", TMPHDR, i, (u_long)ep->e_ino);
        return (name);
}

/*
 * Rename a file or directory.
 */
void
renameit(char *from, char *to)
{
        if (!Nflag && rename(from, to) < 0) {
                fprintf(stderr, "warning: cannot rename %s to %s: %s\n",
                    from, to, strerror(errno));
                return;
        }
        vprintf(stdout, "rename %s to %s\n", from, to);
}

/*
 * Create a new node (directory).
 */
void
newnode(struct entry *np)
{
        char *cp;

        if (np->e_type != NODE)
                badentry(np, "newnode: not a node");
        cp = myname(np);
        if (!Nflag && mkdir(cp, 0777) < 0 && !uflag) {
                np->e_flags |= EXISTED;
                fprintf(stderr, "warning: %s: %s\n", cp, strerror(errno));
                return;
        }
        vprintf(stdout, "Make node %s\n", cp);
}

/*
 * Remove an old node (directory).
 */
void
removenode(struct entry *ep)
{
        char *cp;

        if (ep->e_type != NODE)
                badentry(ep, "removenode: not a node");
        if (ep->e_entries != NULL)
                badentry(ep, "removenode: non-empty directory");
        ep->e_flags |= REMOVED;
        ep->e_flags &= ~TMPNAME;
        cp = myname(ep);
        if (!Nflag && rmdir(cp) < 0) {
                fprintf(stderr, "warning: %s: %s\n", cp, strerror(errno));
                return;
        }
        vprintf(stdout, "Remove node %s\n", cp);
}

/*
 * Remove a leaf.
 */
void
removeleaf(struct entry *ep)
{
        char *cp;

        if (ep->e_type != LEAF)
                badentry(ep, "removeleaf: not a leaf");
        ep->e_flags |= REMOVED;
        ep->e_flags &= ~TMPNAME;
        cp = myname(ep);
        if (!Nflag && unlink(cp) < 0) {
                fprintf(stderr, "warning: %s: %s\n", cp, strerror(errno));
                return;
        }
        vprintf(stdout, "Remove leaf %s\n", cp);
}

/*
 * Create a link.
 */
int
linkit(char *existing, char *new, int type)
{

        /* if we want to unlink first, do it now so *link() won't fail */
        if (uflag && !Nflag)
                (void)unlink(new);

        if (type == SYMLINK) {
                if (!Nflag && symlink(existing, new) < 0) {
                        fprintf(stderr,
                            "warning: cannot create symbolic link %s->%s: %s\n",
                            new, existing, strerror(errno));
                        return (FAIL);
                }
        } else if (type == HARDLINK) {
                int ret;

                if (!Nflag && (ret = link(existing, new)) < 0) {
                        struct stat s;

                        /*
                         * Most likely, the schg flag is set.  Clear the
                         * flags and try again.
                         */
                        if (stat(existing, &s) == 0 && s.st_flags != 0 &&
                            chflags(existing, 0) == 0) {
                                ret = link(existing, new);
                                chflags(existing, s.st_flags);
                        }
                        if (ret < 0) {
                                fprintf(stderr, "warning: cannot create "
                                    "hard link %s->%s: %s\n",
                                    new, existing, strerror(errno));
                                return (FAIL);
                        }
                }
        } else {
                panic("linkit: unknown type %d\n", type);
                return (FAIL);
        }
        vprintf(stdout, "Create %s link %s->%s\n",
                type == SYMLINK ? "symbolic" : "hard", new, existing);
        return (GOOD);
}

/*
 * Create a whiteout.
 */
int
addwhiteout(char *name)
{

        if (!Nflag && mknod(name, S_IFWHT, 0) < 0) {
                fprintf(stderr, "warning: cannot create whiteout %s: %s\n",
                    name, strerror(errno));
                return (FAIL);
        }
        vprintf(stdout, "Create whiteout %s\n", name);
        return (GOOD);
}

/*
 * Delete a whiteout.
 */
void
delwhiteout(struct entry *ep)
{
        char *name;

        if (ep->e_type != LEAF)
                badentry(ep, "delwhiteout: not a leaf");
        ep->e_flags |= REMOVED;
        ep->e_flags &= ~TMPNAME;
        name = myname(ep);
        if (!Nflag && undelete(name) < 0) {
                fprintf(stderr, "warning: cannot delete whiteout %s: %s\n",
                    name, strerror(errno));
                return;
        }
        vprintf(stdout, "Delete whiteout %s\n", name);
}

/*
 * find lowest number file (above "start") that needs to be extracted
 */
ino_t
lowerbnd(ino_t start)
{
        struct entry *ep;

        for ( ; start < maxino; start++) {
                ep = lookupino(start);
                if (ep == NULL || ep->e_type == NODE)
                        continue;
                if (ep->e_flags & (NEW|EXTRACT))
                        return (start);
        }
        return (start);
}

/*
 * find highest number file (below "start") that needs to be extracted
 */
ino_t
upperbnd(ino_t start)
{
        struct entry *ep;

        for ( ; start > UFS_ROOTINO; start--) {
                ep = lookupino(start);
                if (ep == NULL || ep->e_type == NODE)
                        continue;
                if (ep->e_flags & (NEW|EXTRACT))
                        return (start);
        }
        return (start);
}

/*
 * report on a badly formed entry
 */
void
badentry(struct entry *ep, char *msg)
{

        fprintf(stderr, "bad entry: %s\n", msg);
        fprintf(stderr, "name: %s\n", myname(ep));
        fprintf(stderr, "parent name %s\n", myname(ep->e_parent));
        if (ep->e_sibling != NULL)
                fprintf(stderr, "sibling name: %s\n", myname(ep->e_sibling));
        if (ep->e_entries != NULL)
                fprintf(stderr, "next entry name: %s\n", myname(ep->e_entries));
        if (ep->e_links != NULL)
                fprintf(stderr, "next link name: %s\n", myname(ep->e_links));
        if (ep->e_next != NULL)
                fprintf(stderr,
                    "next hashchain name: %s\n", myname(ep->e_next));
        fprintf(stderr, "entry type: %s\n",
                ep->e_type == NODE ? "NODE" : "LEAF");
        fprintf(stderr, "inode number: %lu\n", (u_long)ep->e_ino);
        panic("flags: %s\n", flagvalues(ep));
}

/*
 * Construct a string indicating the active flag bits of an entry.
 */
char *
flagvalues(struct entry *ep)
{
        static char flagbuf[BUFSIZ];

        (void) strcpy(flagbuf, "|NIL");
        flagbuf[0] = '\0';
        if (ep->e_flags & REMOVED)
                (void) strcat(flagbuf, "|REMOVED");
        if (ep->e_flags & TMPNAME)
                (void) strcat(flagbuf, "|TMPNAME");
        if (ep->e_flags & EXTRACT)
                (void) strcat(flagbuf, "|EXTRACT");
        if (ep->e_flags & NEW)
                (void) strcat(flagbuf, "|NEW");
        if (ep->e_flags & KEEP)
                (void) strcat(flagbuf, "|KEEP");
        if (ep->e_flags & EXISTED)
                (void) strcat(flagbuf, "|EXISTED");
        return (&flagbuf[1]);
}

/*
 * Check to see if a name is on a dump tape.
 */
ino_t
dirlookup(const char *name)
{
        struct direct *dp;
        ino_t ino;

        ino = ((dp = pathsearch(name)) == NULL) ? 0 : dp->d_ino;

        if (ino == 0 || TSTINO(ino, dumpmap) == 0)
                fprintf(stderr, "%s is not on the tape\n", name);
        return (ino);
}

/*
 * Elicit a reply.
 */
int
reply(char *question)
{
        int c;

        do      {
                fprintf(stderr, "%s? [yn] ", question);
                (void) fflush(stderr);
                c = getc(terminal);
                while (c != '\n' && getc(terminal) != '\n')
                        if (c == EOF)
                                return (FAIL);
        } while (c != 'y' && c != 'n');
        if (c == 'y')
                return (GOOD);
        return (FAIL);
}

/*
 * handle unexpected inconsistencies
 */
#include <stdarg.h>

void
panic(const char *fmt, ...)
{
        va_list ap;
        va_start(ap, fmt);
        vfprintf(stderr, fmt, ap);
        va_end(ap);
        if (yflag)
                return;
        if (reply("abort") == GOOD) {
                if (reply("dump core") == GOOD)
                        abort();
                done(1);
        }
}