/*      $NetBSD: pathname.c,v 1.2 2022/02/11 10:55:15 hannken Exp $     */

/*-
 * Copyright (c) 2011 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * This code is derived from software contributed to The NetBSD Foundation
 * by UCHIYAMA Yasushi.
 *
 * 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.
 *
 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. 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 FOUNDATION 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/cdefs.h>
#ifndef lint
__RCSID("$NetBSD: pathname.c,v 1.2 2022/02/11 10:55:15 hannken Exp $");
#endif /* not lint */

#include <sys/types.h>
#include <sys/syslimits.h>      /*PATH_MAX */
#include <stdio.h>
#include <string.h>
#include <time.h>

#include "v7fs.h"
#include "v7fs_impl.h"
#include "v7fs_inode.h"
#include "v7fs_datablock.h"
#include "v7fs_superblock.h"
#include "v7fs_dirent.h"
#include "v7fs_file.h"
#include "fsck_v7fs.h"

/*
 * Check pathname. for each inode, check parent, if it is directory,
 * check child.
 */

static int
connect_lost_and_found(struct v7fs_self *fs, v7fs_ino_t ino)
{
        char name[V7FS_NAME_MAX];
        v7fs_time_t t;

        if (!lost_and_found.mode || !reply("CONNECT?"))
                return FSCK_EXIT_CHECK_FAILED;

        snprintf(name, sizeof(name), "%d", ino);
        v7fs_directory_add_entry(fs, &lost_and_found, ino, name, strlen(name));
        t = (v7fs_time_t)time(NULL);
        lost_and_found.mtime = lost_and_found.atime = t;
        v7fs_inode_writeback(fs, &lost_and_found);
        v7fs_superblock_writeback(fs); /* # of freeblocks may change. */

        return 0;
}

/* Check child (dir) */
struct lookup_child_arg {
        int dir_cnt;
        bool print;
        struct v7fs_inode *parent;
};

static int
lookup_child_subr(struct v7fs_self *fs, void *ctx, v7fs_daddr_t blk, size_t sz)
{
        struct lookup_child_arg *arg = (struct lookup_child_arg *)ctx;
        void *buf;
        int error = 0;

        if (!(buf = scratch_read(fs, blk)))
                return 0;
        struct v7fs_dirent *dir = (struct v7fs_dirent *)buf;
        size_t i, n = sz / sizeof(*dir);
        if (!v7fs_dirent_endian_convert(fs, dir, n)) {
                pwarn("*** bogus entry found *** dir#%d entry=%zu\n",
                    arg->parent->inode_number, n);
                arg->print = true;
        }

        for (i = 0; i < n; i++, dir++) {
                struct v7fs_inode inode;
                if (arg->print)
                        pwarn("%s %d\n", dir->name, dir->inode_number);
                /* Bogus enties are removed here. */
                if ((error = v7fs_inode_load(fs, &inode, dir->inode_number)))
                {
                        pwarn("entry #%d not found.", dir->inode_number);
                        if (reply("REMOVE?"))
                                v7fs_directory_remove_entry(fs, arg->parent,
                                    dir->name, strlen(dir->name));
                } else {
                        /* Count child dir. */
                        if (v7fs_inode_isdir(&inode))
                                arg->dir_cnt++;
                }
        }
        scratch_free(fs, buf);

        return error;
}

static int
lookup_child_from_dir(struct v7fs_self *fs, struct v7fs_inode *p, bool print)
{
        struct lookup_child_arg arg = { .dir_cnt = 0, .print = print,
            .parent = p };

        v7fs_datablock_foreach(fs, p, lookup_child_subr, &arg);

        return arg.dir_cnt;
}

/* Find parent directory (file) */
struct lookup_parent_arg {
        v7fs_ino_t target_ino;
        v7fs_ino_t parent_ino;
};

static int
lookup_parent_from_file_subr(struct v7fs_self *fs, void *ctx,
    struct v7fs_inode *p, v7fs_ino_t ino)
{
        struct lookup_parent_arg *arg = (struct lookup_parent_arg *)ctx;

        if (!v7fs_inode_isdir(p))
                return 0;

        if (v7fs_file_lookup_by_number(fs, p, arg->target_ino, NULL)) {
                arg->parent_ino = ino; /* My inode found. */
                return V7FS_ITERATOR_BREAK;
        }

        return 0; /* not found. */
}


static v7fs_ino_t
lookup_parent_from_file(struct v7fs_self *fs, v7fs_ino_t ino)
{
        struct lookup_parent_arg arg = { .target_ino = ino, .parent_ino = 0 };

        v7fs_ilist_foreach(fs, lookup_parent_from_file_subr, &arg);

        return arg.parent_ino;
}

/* Find parent directory (dir) */
static int
lookup_parent_from_dir_subr(struct v7fs_self *fs, void *ctx, v7fs_daddr_t blk,
    size_t sz)
{
        struct lookup_parent_arg *arg = (struct lookup_parent_arg *)ctx;
        void *buf;
        int ret = 0;

        if (!(buf = scratch_read(fs, blk)))
                return 0;
        struct v7fs_dirent *dir = (struct v7fs_dirent *)buf;
        size_t i, n = sz / sizeof(*dir);
        if (!v7fs_dirent_endian_convert(fs, dir, n)) {
                scratch_free(fs, buf);
                return V7FS_ITERATOR_ERROR;
        }

        for (i = 0; i < n; i++, dir++) {
                if (strncmp(dir->name, "..", 2) != 0)
                        continue;

                arg->parent_ino = dir->inode_number;
                ret = V7FS_ITERATOR_BREAK;
                break;
        }

        scratch_free(fs, buf);
        return ret;
}

static v7fs_ino_t
lookup_parent_from_dir(struct v7fs_self *fs, struct v7fs_inode *p)
{
        struct lookup_parent_arg arg = { .target_ino = 0, .parent_ino = 0 };

        /* Search parent("..") from my dirent. */
        v7fs_datablock_foreach(fs, p, lookup_parent_from_dir_subr, &arg);

        return arg.parent_ino;
}

static int
pathname_check_file(struct v7fs_self *fs, struct v7fs_inode *p, v7fs_ino_t ino)
{
        v7fs_ino_t parent_ino;
        struct v7fs_inode parent_inode;
        int error = 0;

        if (ino == 1)   /* reserved. */
                return 0;

        /* Check parent. */
        if (!(parent_ino = lookup_parent_from_file(fs, ino)) ||
            (error = v7fs_inode_load(fs, &parent_inode, parent_ino)) ||
            !v7fs_inode_isdir(&parent_inode)) {
                pwarn("*** inode#%d don't have parent.", ino);
                v7fs_inode_dump(p);
                error = connect_lost_and_found(fs, ino);
        }

        return error;
}

static int
pathname_check_dir(struct v7fs_self *fs, struct v7fs_inode *p, v7fs_ino_t ino)
{
        v7fs_ino_t parent_ino;
        struct v7fs_inode parent_inode;
        int error = 0;

        /* Check parent */
        if (!(parent_ino = lookup_parent_from_dir(fs, p)) ||
            (error = v7fs_inode_load(fs, &parent_inode, parent_ino)) ||
            !v7fs_inode_isdir(&parent_inode)) {
                pwarn("*** ino#%d parent dir missing parent=%d", ino,
                    parent_ino);
                /* link to lost+found */
                v7fs_inode_dump(p);
                if ((error = connect_lost_and_found(fs, ino)))
                        return error;
        }

        /* Check child */
        int cnt = lookup_child_from_dir(fs, p, false);
        if ((error = (cnt != p->nlink))) {
                pwarn("*** ino#%d corrupt link # of child"
                    " dir:%d(inode) != %d(cnt)", ino, p->nlink, cnt);
                v7fs_inode_dump(p);
                lookup_child_from_dir(fs, p, true);

                if (reply("CORRECT?")) {
                        p->nlink = cnt;
                        v7fs_inode_writeback(fs, p);
                        error = 0;
                } else {
                        error = FSCK_EXIT_CHECK_FAILED;
                }
        }

        return error;
}

static int
pathname_subr(struct v7fs_self *fs, void *ctx __unused, struct v7fs_inode *p,
    v7fs_ino_t ino)
{
        int error = 0;

        if (!v7fs_inode_allocated(p))
                return 0;

        progress(0);

        if (v7fs_inode_isdir(p)) {
                error = pathname_check_dir(fs, p, ino);
        } else if (v7fs_inode_isfile(p)) {
                error = pathname_check_file(fs, p, ino);
        }

        return error;
}

int
pathname_check(struct v7fs_self *fs)
{
        struct v7fs_superblock *sb = &fs->superblock;
        int inodes = V7FS_MAX_INODE(sb) - sb->total_freeinode;

        progress(&(struct progress_arg){ .label = "pathname", .tick = inodes /
            PROGRESS_BAR_GRANULE });

        return v7fs_ilist_foreach(fs, pathname_subr, 0);
}


char *
filename(struct v7fs_self *fs, v7fs_ino_t ino)
{
        static char path[V7FS_PATH_MAX];
        struct v7fs_inode inode;
        v7fs_ino_t parent;
        int error;
        char name[V7FS_NAME_MAX + 1];
        char *p = path + V7FS_PATH_MAX;
        size_t n;

        if ((error = v7fs_inode_load(fs, &inode, ino)))
                return 0;

        /* Lookup the 1st parent. */
        if (v7fs_inode_isdir(&inode))
                parent = lookup_parent_from_dir(fs, &inode);
        else
                parent = lookup_parent_from_file(fs, ino);

        if ((error = v7fs_inode_load(fs, &inode, parent)))
                return 0;

        if (!v7fs_file_lookup_by_number(fs, &inode, ino, name))
                return 0;

        n = strlen(name) + 1;
        strcpy(p -= n, name);

        /* Lookup until / */
        ino = parent;
        while (parent != V7FS_ROOT_INODE) {
                parent = lookup_parent_from_dir(fs, &inode);
                if ((error = v7fs_inode_load(fs, &inode, parent)))
                        return 0;
                if (!v7fs_file_lookup_by_number(fs, &inode, ino, name))
                        return 0;
                ino = parent;
                n = strlen(name) + 1;
                strcpy(p - n, name);
                p[-1] = '/';
                p -= n;
        }
        *--p = '/';

        return p;
}