/*-
 * SPDX-License-Identifier: BSD-2-Clause
 *
 * Copyright (c) 2007 Pawel Jakub Dawidek <pjd@FreeBSD.org>
 * 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.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHORS 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 AUTHORS 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/disk.h>
#include <sys/stat.h>

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

#include <libgeom.h>

static char     *g_device_path_open(const char *, int *, int);

/*
 * Open the given provider and at least check if this is a block device.
 */
int
g_open(const char *name, int dowrite)
{
        char *path;
        int fd;

        path = g_device_path_open(name, &fd, dowrite);
        if (path != NULL)
                free(path);
        return (fd);
}

int
g_close(int fd)
{

        return (close(fd));
}

static int
g_ioctl_arg(int fd, unsigned long cmd, void *arg)
{
        int ret;

        if (arg != NULL)
                ret = ioctl(fd, cmd, arg);
        else
                ret = ioctl(fd, cmd);
        return (ret >= 0 ? 0 : -1);
}

static int
g_ioctl(int fd, unsigned long cmd)
{

        return (g_ioctl_arg(fd, cmd, NULL));
}

/*
 * Return media size of the given provider.
 */
off_t
g_mediasize(int fd)
{
        off_t mediasize;

        if (g_ioctl_arg(fd, DIOCGMEDIASIZE, &mediasize) == -1)
                mediasize = -1;
        return (mediasize);
}

/*
 * Return sector size of the given provider.
 */
ssize_t
g_sectorsize(int fd)
{
        u_int sectorsize;

        if (g_ioctl_arg(fd, DIOCGSECTORSIZE, &sectorsize) == -1)
                return (-1);
        return ((ssize_t)sectorsize);
}

/*
 * Return stripe size of the given provider.
 */
off_t
g_stripesize(int fd)
{
        off_t stripesize;

        if (g_ioctl_arg(fd, DIOCGSTRIPESIZE, &stripesize) == -1)
                return (-1);
        return (stripesize);
}

/*
 * Return stripe size of the given provider.
 */
off_t
g_stripeoffset(int fd)
{
        off_t stripeoffset;

        if (g_ioctl_arg(fd, DIOCGSTRIPEOFFSET, &stripeoffset) == -1)
                return (-1);
        return (stripeoffset);
}

/*
 * Return the correct provider name.
 */
char *
g_providername(int fd)
{
        char name[MAXPATHLEN];

        if (g_ioctl_arg(fd, DIOCGPROVIDERNAME, name) == -1)
                return (NULL);
        return (strdup(name));
}

/*
 * Call BIO_FLUSH for the given provider.
 */
int
g_flush(int fd)
{

        return (g_ioctl(fd, DIOCGFLUSH));
}

/*
 * Call BIO_DELETE for the given range.
 */
int
g_delete(int fd, off_t offset, off_t length)
{
        off_t arg[2];

        arg[0] = offset;
        arg[1] = length;
        return (g_ioctl_arg(fd, DIOCGDELETE, arg));
}

/*
 * Return ID of the given provider.
 */
int
g_get_ident(int fd, char *ident, size_t size)
{
        char lident[DISK_IDENT_SIZE];

        if (g_ioctl_arg(fd, DIOCGIDENT, lident) == -1)
                return (-1);
        if (lident[0] == '\0') {
                errno = ENOENT;
                return (-1);
        }
        if (strlcpy(ident, lident, size) >= size) {
                errno = ENAMETOOLONG;
                return (-1);
        }
        return (0);
}

/*
 * Return name of the provider, which has the given ID.
 */
int
g_get_name(const char *ident, char *name, size_t size)
{
        int fd;

        fd = g_open_by_ident(ident, 0, name, size);
        if (fd == -1)
                return (-1);
        g_close(fd);
        return (0);
}

/*
 * Find provider name by the given ID.
 */
int
g_open_by_ident(const char *ident, int dowrite, char *name, size_t size)
{
        char lident[DISK_IDENT_SIZE];
        struct gmesh mesh;
        struct gclass *mp;
        struct ggeom *gp;
        struct gprovider *pp;
        int error, fd;

        error = geom_gettree(&mesh);
        if (error != 0) {
                errno = error;
                return (-1);
        }

        error = ENOENT;
        fd = -1;

        LIST_FOREACH(mp, &mesh.lg_class, lg_class) {
                LIST_FOREACH(gp, &mp->lg_geom, lg_geom) {
                        LIST_FOREACH(pp, &gp->lg_provider, lg_provider) {
                                fd = g_open(pp->lg_name, dowrite);
                                if (fd == -1)
                                        continue;
                                if (g_get_ident(fd, lident,
                                    sizeof(lident)) == -1) {
                                        g_close(fd);
                                        continue;
                                }
                                if (strcmp(ident, lident) != 0) {
                                        g_close(fd);
                                        continue;
                                }
                                error = 0;
                                if (name != NULL && strlcpy(name, pp->lg_name,
                                    size) >= size) {
                                        error = ENAMETOOLONG;
                                        g_close(fd);
                                }
                                goto end;
                        }
                }
        }
end:
        geom_deletetree(&mesh);
        if (error != 0) {
                errno = error;
                return (-1);
        }
        return (fd);
}

/*
 * Return the device path device given a partial or full path to its node.
 * A pointer can be provided, which will be set to an opened file descriptor of
 * not NULL.
 */
static char *
g_device_path_open(const char *devpath, int *fdp, int dowrite)
{
        char *path;
        int fd;

        /* Make sure that we can fail. */
        if (fdp != NULL)
                *fdp = -1;

        /* Use the device node if we're able to open it. */
        fd = open(devpath, dowrite ? O_RDWR : O_RDONLY);
        if (fd != -1) {
                if ((path = strdup(devpath)) == NULL) {
                        close(fd);
                        return (NULL);
                }
                goto fd_ok;
        }

        /* If we're not given an absolute path, assume /dev/ prefix. */
        if (*devpath == '/')
                return (NULL);

        asprintf(&path, "%s%s", _PATH_DEV, devpath);
        if (path == NULL)
                return (NULL);
        fd = open(path, dowrite ? O_RDWR : O_RDONLY);
        if (fd == -1) {
                free(path);
                return (NULL);
        }

fd_ok:
        /*
         * Let try to get sectorsize, which will prove it is a GEOM provider.
         */
        if (g_sectorsize(fd) == -1) {
                free(path);
                close(fd);
                errno = EFTYPE;
                return (NULL);
        }
        if (fdp != NULL)
                *fdp = fd;
        else
                close(fd);
        return (path);
}

char *
g_device_path(const char *devpath)
{
        return (g_device_path_open(devpath, NULL, 0));
}