path_id.c revision 48a9b173e88738ff4eefb3519f1d27711b417c8d
/*
* compose persisistent device path
*
* Copyright (C) 2009 Kay Sievers <kay.sievers@vrfy.org>
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <stdio.h>
#include <stdlib.h>
#include <stdarg.h>
#include <unistd.h>
#include <string.h>
#include <ctype.h>
#include <fcntl.h>
#include <errno.h>
#include <dirent.h>
#include <getopt.h>
#include "libudev.h"
#include "../../udev/udev.h"
int debug;
static void log_fn(struct udev *udev, int priority,
const char *file, int line, const char *fn,
const char *format, va_list args)
{
if (debug) {
fprintf(stderr, "%s: ", fn != NULL ? fn : file);
vfprintf(stderr, format, args);
} else {
vsyslog(priority, format, args);
}
}
static int path_prepend(char **path, const char *fmt, ...)
{
va_list va;
char *old;
char *pre;
int err;
old = *path;
va_start(va, fmt);
err = vasprintf(&pre, fmt, va);
va_end(va);
if (err < 0)
return err;
if (old != NULL) {
err = asprintf(path, "%s-%s", pre, old);
if (err < 0)
return err;
free(pre);
} else {
*path = pre;
}
free(old);
return 0;
}
static struct udev_device *skip_subsystem(struct udev_device *dev, const char *subsys)
{
struct udev_device *parent = dev;
while (parent != NULL) {
const char *subsystem;
subsystem = udev_device_get_subsystem(parent);
if (subsystem == NULL || strcmp(subsystem, subsys) != 0)
break;
dev = parent;
parent = udev_device_get_parent(parent);
}
return dev;
}
static struct udev_device *handle_scsi_fibre_channel(struct udev_device *parent, char **path)
{
struct udev *udev = udev_device_get_udev(parent);
struct udev_device *targetdev;
struct udev_device *fcdev = NULL;
const char *port;
unsigned int lun;
targetdev = udev_device_get_parent_with_subsystem_devtype(parent, "scsi", "scsi_target");
if (targetdev == NULL)
return NULL;
fcdev = udev_device_new_from_subsystem_sysname(udev, "fc_transport", udev_device_get_sysname(targetdev));
if (fcdev == NULL)
return NULL;
port = udev_device_get_sysattr_value(fcdev, "port_name");
if (port == NULL) {
parent = NULL;
goto out;
}
lun = strtoul(udev_device_get_sysnum(parent), NULL, 10);
path_prepend(path, "fc-%s:0x%04x%04x00000000", port, lun & 0xffff, (lun >> 16) & 0xffff);
out:
udev_device_unref(fcdev);
return parent;
}
static struct udev_device *handle_scsi_sas(struct udev_device *parent, char **path)
{
return NULL;
}
static struct udev_device *handle_scsi_iscsi(struct udev_device *parent, char **path)
{
struct udev *udev = udev_device_get_udev(parent);
struct udev_device *transportdev;
struct udev_device *sessiondev = NULL;
const char *target;
char *connname;
struct udev_device *conndev = NULL;
const char *addr;
const char *port;
/* find iscsi session */
transportdev = parent;
while (1) {
transportdev = udev_device_get_parent(transportdev);
if (transportdev == NULL)
return NULL;
if (strncmp(udev_device_get_sysname(transportdev), "session", 7) == 0)
break;
}
if (transportdev == NULL)
return NULL;
/* find iscsi session device */
sessiondev = udev_device_new_from_subsystem_sysname(udev, "iscsi_session", udev_device_get_sysname(transportdev));
if (sessiondev == NULL)
return NULL;
target = udev_device_get_sysattr_value(sessiondev, "targetname");
if (target == NULL) {
parent = NULL;
goto out;
}
if (asprintf(&connname, "connection%s:0", udev_device_get_sysnum(transportdev)) < 0) {
parent = NULL;
goto out;
}
conndev = udev_device_new_from_subsystem_sysname(udev, "iscsi_connection", connname);
free(connname);
if (conndev == NULL) {
parent = NULL;
goto out;
}
addr = udev_device_get_sysattr_value(conndev, "persistent_address");
port = udev_device_get_sysattr_value(conndev, "persistent_port");
if (addr == NULL || port == NULL) {
parent = NULL;
goto out;
}
path_prepend(path, "ip-%s:%s-iscsi-%s-lun-%s", addr, port, target, udev_device_get_sysnum(parent));
out:
udev_device_unref(sessiondev);
udev_device_unref(conndev);
return parent;
}
static struct udev_device *handle_scsi_default(struct udev_device *parent, char **path)
{
struct udev_device *hostdev;
int host, bus, target, lun;
const char *name;
char *base;
char *pos;
DIR *dir;
struct dirent *dent;
int basenum;
hostdev = udev_device_get_parent_with_subsystem_devtype(parent, "scsi", "scsi_host");
if (hostdev == NULL)
return NULL;
name = udev_device_get_sysname(parent);
if (sscanf(name, "%d:%d:%d:%d", &host, &bus, &target, &lun) != 4)
return NULL;
/* rebase host offset to get the local relative number */
basenum = -1;
base = strdup(udev_device_get_syspath(hostdev));
if (base == NULL)
return NULL;
pos = strrchr(base, '/');
if (pos == NULL) {
parent = NULL;
goto out;
}
pos[0] = '\0';
dir = opendir(base);
if (dir == NULL) {
parent = NULL;
goto out;
}
for (dent = readdir(dir); dent != NULL; dent = readdir(dir)) {
char *rest;
int i;
if (dent->d_name[0] == '.')
continue;
if (dent->d_type != DT_DIR && dent->d_type != DT_LNK)
continue;
if (strncmp(dent->d_name, "host", 4) != 0)
continue;
i = strtoul(&dent->d_name[4], &rest, 10);
if (rest[0] != '\0')
continue;
if (basenum == -1 || i < basenum)
basenum = i;
}
closedir(dir);
if (basenum == -1) {
parent = NULL;
goto out;
}
host -= basenum;
path_prepend(path, "scsi-%u:%u:%u:%u", host, bus, target, lun);
out:
free(base);
return hostdev;
}
static struct udev_device *handle_scsi(struct udev_device *parent, char **path)
{
const char *devtype;
const char *name;
const char *id;
devtype = udev_device_get_devtype(parent);
if (devtype == NULL || strcmp(devtype, "scsi_device") != 0)
return parent;
/* firewire */
id = udev_device_get_sysattr_value(parent, "ieee1394_id");
if (id != NULL) {
parent = skip_subsystem(parent, "scsi");
path_prepend(path, "ieee1394-0x%s", id);
goto out;
}
/* lousy scsi sysfs does not have a "subsystem" for the transport */
name = udev_device_get_syspath(parent);
if (strstr(name, "/rport-") != NULL) {
parent = handle_scsi_fibre_channel(parent, path);
goto out;
}
if (strstr(name, "/end_device-") != NULL) {
parent = handle_scsi_sas(parent, path);
goto out;
}
if (strstr(name, "/session") != NULL) {
parent = handle_scsi_iscsi(parent, path);
goto out;
}
parent = handle_scsi_default(parent, path);
out:
return parent;
}
static void handle_scsi_tape(struct udev_device *dev, char **suffix)
{
const char *name;
name = udev_device_get_sysname(dev);
if (strncmp(name, "nst", 3) == 0 && strchr("lma", name[3]) != NULL)
asprintf(suffix, "nst%c", name[3]);
else if (strncmp(name, "st", 2) == 0 && strchr("lma", name[2]) != NULL)
asprintf(suffix, "st%c", name[2]);
}
static struct udev_device *handle_usb(struct udev_device *parent, char **path)
{
const char *devtype;
const char *str;
const char *port;
devtype = udev_device_get_devtype(parent);
if (devtype == NULL || strcmp(devtype, "usb_interface") != 0)
return parent;
str = udev_device_get_sysname(parent);
port = strchr(str, '-');
if (port == NULL)
return parent;
port++;
parent = skip_subsystem(parent, "usb");
path_prepend(path, "usb-0:%s", port);
return parent;
}
static struct udev_device *handle_cciss(struct udev_device *parent, char **path)
{
return NULL;
}
static struct udev_device *handle_ccw(struct udev_device *parent, struct udev_device *dev, char **path)
{
struct udev_device *scsi_dev;
scsi_dev = udev_device_get_parent_with_subsystem_devtype(dev, "scsi", "scsi_device");
if (scsi_dev != NULL) {
const char *wwpn;
const char *lun;
const char *hba_id;
hba_id = udev_device_get_sysattr_value(scsi_dev, "hba_id");
wwpn = udev_device_get_sysattr_value(scsi_dev, "wwpn");
lun = udev_device_get_sysattr_value(scsi_dev, "fcp_lun");
if (hba_id != NULL && lun != NULL && wwpn != NULL) {
path_prepend(path, "ccw-%s-zfcp-%s:%s", hba_id, wwpn, lun);
goto out;
}
}
path_prepend(path, "ccw-%s", udev_device_get_sysname(parent));
out:
parent = skip_subsystem(parent, "ccw");
return parent;
}
int main(int argc, char **argv)
{
static const struct option options[] = {
{ "debug", no_argument, NULL, 'd' },
{ "help", no_argument, NULL, 'h' },
{}
};
struct udev *udev;
struct udev_device *dev;
struct udev_device *parent;
char syspath[UTIL_PATH_SIZE];
const char *devpath;
char *path;
char *path_suffix;
int rc = 1;
udev = udev_new();
if (udev == NULL)
goto exit;
logging_init("path_id");
udev_set_log_fn(udev, log_fn);
while (1) {
int option;
option = getopt_long(argc, argv, "dh", options, NULL);
if (option == -1)
break;
switch (option) {
case 'd':
debug = 1;
if (udev_get_log_priority(udev) < LOG_INFO)
udev_set_log_priority(udev, LOG_INFO);
break;
case 'h':
printf("Usage: path_id [--debug] [--help] <devpath>\n"
" --debug print debug information\n"
" --help print this help text\n\n");
default:
rc = 1;
goto exit;
}
}
devpath = argv[optind];
if (devpath == NULL) {
fprintf(stderr, "No device specified\n");
rc = 2;
goto exit;
}
util_strscpyl(syspath, sizeof(syspath), udev_get_sys_path(udev), devpath, NULL);
dev = udev_device_new_from_syspath(udev, syspath);
if (dev == NULL) {
fprintf(stderr, "unable to access '%s'\n", devpath);
rc = 3;
goto exit;
}
path = NULL;
path_suffix = NULL;
/* S390 ccw bus */
parent = udev_device_get_parent_with_subsystem_devtype(dev, "ccw", NULL);
if (parent != NULL) {
handle_ccw(parent, dev, &path);
goto out;
}
/* walk up the chain of devices and compose path */
parent = dev;
while (parent != NULL) {
const char *subsys;
subsys = udev_device_get_subsystem(parent);
if (subsys == NULL) {
;
} else if (strcmp(subsys, "scsi_tape") == 0) {
handle_scsi_tape(parent, &path_suffix);
} else if (strcmp(subsys, "scsi") == 0) {
parent = handle_scsi(parent, &path);
} else if (strcmp(subsys, "cciss") == 0) {
handle_cciss(parent, &path);
} else if (strcmp(subsys, "usb") == 0) {
parent = handle_usb(parent, &path);
} else if (strcmp(subsys, "serio") == 0) {
path_prepend(&path, "serio-%s", udev_device_get_sysnum(parent));
parent = skip_subsystem(parent, "serio");
} else if (strcmp(subsys, "pci") == 0) {
path_prepend(&path, "pci-%s", udev_device_get_sysname(parent));
parent = skip_subsystem(parent, "pci");
} else if (strcmp(subsys, "platform") == 0) {
path_prepend(&path, "platform-%s", udev_device_get_sysname(parent));
parent = skip_subsystem(parent, "platform");
} else if (strcmp(subsys, "xen") == 0) {
path_prepend(&path, "xen-%s", udev_device_get_sysname(parent));
parent = skip_subsystem(parent, "xen");
}
parent = udev_device_get_parent(parent);
}
out:
if (path != NULL) {
if (path_suffix != NULL) {
printf("ID_PATH=%s%s\n", path, path_suffix);
free(path_suffix);
} else {
printf("ID_PATH=%s\n", path);
}
free(path);
rc = 0;
}
udev_device_unref(dev);
exit:
udev_unref(udev);
logging_close();
return rc;
}