/*-
 * SPDX-License-Identifier: BSD-2-Clause
 *
 * Copyright (c) 2002 Juli Mallett.  All rights reserved.
 *
 * This software was written by Juli Mallett <jmallett@FreeBSD.org> for the
 * FreeBSD project.  Redistribution and use in source and binary forms, with
 * or without modification, are permitted provided that the following
 * conditions are met:
 *
 * 1. Redistribution of source code must retain the above copyright notice,
 *    this list of conditions and the following disclaimer.
 * 2. Redistribution 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 AUTHOR ``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 AUTHOR 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/mount.h>
#include <sys/disklabel.h>
#include <sys/stat.h>

#include <ufs/ufs/extattr.h>
#include <ufs/ufs/quota.h>
#include <ufs/ufs/ufsmount.h>
#include <ufs/ufs/dinode.h>
#include <ufs/ffs/fs.h>

#include <errno.h>
#include <fcntl.h>
#include <fstab.h>
#include <paths.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#include <libufs.h>

/* Internally, track the 'name' value, it's ours. */
#define MINE_NAME       0x01
/* Track if its fd points to a writable device. */
#define MINE_WRITE      0x02

int
ufs_disk_close(struct uufsd *disk)
{
        ERROR(disk, NULL);
        close(disk->d_fd);
        disk->d_fd = -1;
        if (disk->d_mine & MINE_NAME) {
                free((char *)(uintptr_t)disk->d_name);
                disk->d_name = NULL;
        }
        if (disk->d_si != NULL) {
                free(disk->d_si->si_csp);
                free(disk->d_si);
                disk->d_si = NULL;
        }
        return (0);
}

int
ufs_disk_fillout(struct uufsd *disk, const char *name)
{
        if (ufs_disk_fillout_blank(disk, name) == -1) {
                return (-1);
        }
        if (sbread(disk) == -1) {
                ERROR(disk, "could not read superblock to fill out disk");
                ufs_disk_close(disk);
                return (-1);
        }
        return (0);
}

int
ufs_disk_fillout_blank(struct uufsd *disk, const char *name)
{
        struct stat st;
        struct fstab *fs;
        struct statfs sfs;
        const char *oname;
        char dev[MAXPATHLEN];
        int fd, ret;

        ERROR(disk, NULL);

        oname = name;
again:  if ((ret = stat(name, &st)) < 0) {
                if (*name != '/') {
                        snprintf(dev, sizeof(dev), "%s%s", _PATH_DEV, name);
                        name = dev;
                        goto again;
                }
                /*
                 * The given object doesn't exist, but don't panic just yet -
                 * it may be still mount point listed in /etc/fstab, but without
                 * existing corresponding directory.
                 */
                name = oname;
        }
        if (ret >= 0 && S_ISREG(st.st_mode)) {
                /* Possibly a disk image, give it a try.  */
                ;
        } else if (ret >= 0 && S_ISCHR(st.st_mode)) {
                /* This is what we need, do nothing. */
                ;
        } else if ((fs = getfsfile(name)) != NULL) {
                /*
                 * The given mount point is listed in /etc/fstab.
                 * It is possible that someone unmounted file system by hand
                 * and different file system is mounted on this mount point,
                 * but we still prefer /etc/fstab entry, because on the other
                 * hand, there could be /etc/fstab entry for this mount
                 * point, but file system is not mounted yet (eg. noauto) and
                 * statfs(2) will point us at different file system.
                 */
                name = fs->fs_spec;
        } else if (ret >= 0 && S_ISDIR(st.st_mode)) {
                /*
                 * The mount point is not listed in /etc/fstab, so it may be
                 * file system mounted by hand.
                 */
                if (statfs(name, &sfs) < 0) {
                        ERROR(disk, "could not find special device");
                        return (-1);
                }
                strlcpy(dev, sfs.f_mntfromname, sizeof(dev));
                name = dev;
        } else {
                ERROR(disk, "could not find special device");
                return (-1);
        }
        fd = open(name, O_RDONLY);
        if (fd == -1) {
                ERROR(disk, "could not open special device");
                return (-1);
        }

        if (((uintptr_t)disk & ~(LIBUFS_BUFALIGN - 1)) != (uintptr_t)disk) {
                ERROR(disk, "uufsd structure must be aligned to "
                    "LIBUFS_BUFALIGN byte boundry, see ufs_disk_fillout(3)");
                close(fd);
                return (-1);
        }

        disk->d_bsize = 1;
        disk->d_ccg = 0;
        disk->d_fd = fd;
        disk->d_inomin = 0;
        disk->d_inomax = 0;
        disk->d_lcg = 0;
        disk->d_mine = 0;
        disk->d_ufs = 0;
        disk->d_error = NULL;
        disk->d_si = NULL;
        disk->d_sblockloc = UFS_STDSB;
        disk->d_lookupflags = 0;

        if (oname != name) {
                name = strdup(name);
                if (name == NULL) {
                        ERROR(disk, "could not allocate memory for disk name");
                        return (-1);
                }
                disk->d_mine |= MINE_NAME;
        }
        disk->d_name = name;

        return (0);
}

int
ufs_disk_write(struct uufsd *disk)
{
        int fd;

        ERROR(disk, NULL);

        if (disk->d_mine & MINE_WRITE)
                return (0);

        fd = open(disk->d_name, O_RDWR);
        if (fd < 0) {
                ERROR(disk, "failed to open disk for writing");
                return (-1);
        }

        close(disk->d_fd);
        disk->d_fd = fd;
        disk->d_mine |= MINE_WRITE;

        return (0);
}