zfs-builds-mm/zfs-0.8.0/tests/zfs-tests/cmd/devname2devid/devname2devid.c
2019-07-06 23:40:11 +02:00

160 lines
3.7 KiB
C

/*
* 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 2007 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*
* Copyright (c) 2016, Intel Corporation.
*/
#include <sys/types.h>
#include <sys/param.h>
#include <sys/stat.h>
#include <libudev.h>
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <fcntl.h>
/*
* Linux persistent device strings for vdev labels
*
* based on udev_device_get_devid() at zfs/lib/libzfs/libzfs_import.c
*/
#define DEV_BYID_PATH "/dev/disk/by-id/"
static int
udev_device_get_devid(struct udev_device *dev, char *bufptr, size_t buflen)
{
struct udev_list_entry *entry;
const char *bus;
char devbyid[MAXPATHLEN];
/* The bus based by-id path is preferred */
bus = udev_device_get_property_value(dev, "ID_BUS");
if (bus == NULL) {
const char *dm_uuid;
/*
* For multipath nodes use the persistent uuid based identifier
*
* Example: 'dm-uuid-mpath-35000c5006304de3f'
*/
dm_uuid = udev_device_get_property_value(dev, "DM_UUID");
if (dm_uuid != NULL) {
(void) snprintf(bufptr, buflen, "dm-uuid-%s", dm_uuid);
return (0);
}
return (ENODATA);
}
/*
* locate the bus specific by-id link
*
* Example: 'scsi-MG03SCA300_350000494a8cb3d67-part1'
*/
(void) snprintf(devbyid, sizeof (devbyid), "%s%s-", DEV_BYID_PATH, bus);
entry = udev_device_get_devlinks_list_entry(dev);
while (entry != NULL) {
const char *name;
name = udev_list_entry_get_name(entry);
if (strncmp(name, devbyid, strlen(devbyid)) == 0) {
name += strlen(DEV_BYID_PATH);
(void) stpncpy(bufptr, name, buflen - 1);
bufptr[buflen - 1] = '\0';
return (0);
}
entry = udev_list_entry_get_next(entry);
}
return (ENODATA);
}
/*
* Usage: devname2devid <devicepath>
*
* Examples:
* # ./devname2devid /dev/sda1
* devid scsi-350000394a8caede4-part1
*
* # ./devname2devid /dev/dm-1
* devid: 'dm-uuid-mpath-35000c5006304de3f'
*
* This program accepts a disk or disk slice path and prints a
* device id.
*
* Exit values:
* 0 - means success
* 1 - means failure
*
*/
int
main(int argc, char *argv[])
{
struct udev *udev;
struct udev_device *dev = NULL;
char devid[128], nodepath[MAXPATHLEN];
char *device, *sysname;
int ret;
if (argc == 1) {
(void) printf("%s <devicepath> [search path]\n", argv[0]);
exit(1);
}
device = argv[1];
if ((udev = udev_new()) == NULL) {
perror("udev_new");
exit(1);
}
/* resolve path to a runtime device node instance */
if (realpath(device, nodepath) == NULL) {
perror("realpath");
exit(1);
}
sysname = strrchr(nodepath, '/') + 1;
if ((dev = udev_device_new_from_subsystem_sysname(udev, "block",
sysname)) == NULL) {
perror(sysname);
exit(1);
}
if ((ret = udev_device_get_devid(dev, devid, sizeof (devid))) != 0) {
udev_device_unref(dev);
errno = ret;
perror(sysname);
exit(1);
}
(void) printf("devid %s\n", devid);
udev_device_unref(dev);
udev_unref(udev);
return (0);
}