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Systemd/src/libudev/libudev-device.c
Robert Milasan 572016d1c2 udev: fix path for database names on 'change' event 
If a device does not have a major/minor number attached, we use different
database names than if it does. On "change" events, we didn't copy the
devnum over, therefore, we used different paths than on 'add' or 'remove'
events (where devnum was properly copied).

Fix this by always copying the devnum into the udev-device.

(David: added commit-log from email)
2014-09-18 15:28:07 +02:00

1927 lines
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/***
This file is part of systemd.
Copyright 2008-2012 Kay Sievers <kay@vrfy.org>
systemd is free software; you can redistribute it and/or modify it
under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2.1 of the License, or
(at your option) any later version.
systemd 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License
along with systemd; If not, see <http://www.gnu.org/licenses/>.
***/
#include <stdio.h>
#include <stdlib.h>
#include <stddef.h>
#include <unistd.h>
#include <stdbool.h>
#include <errno.h>
#include <string.h>
#include <dirent.h>
#include <fcntl.h>
#include <ctype.h>
#include <net/if.h>
#include <sys/stat.h>
#include <sys/ioctl.h>
#include <sys/socket.h>
#include <linux/sockios.h>
#include "libudev.h"
#include "libudev-private.h"
static int udev_device_set_devnode(struct udev_device *udev_device, const char *devnode);
/**
* SECTION:libudev-device
* @short_description: kernel sys devices
*
* Representation of kernel sys devices. Devices are uniquely identified
* by their syspath, every device has exactly one path in the kernel sys
* filesystem. Devices usually belong to a kernel subsystem, and have
* a unique name inside that subsystem.
*/
/**
* udev_device:
*
* Opaque object representing one kernel sys device.
*/
struct udev_device {
struct udev *udev;
struct udev_device *parent_device;
char *syspath;
const char *devpath;
char *sysname;
const char *sysnum;
char *devnode;
mode_t devnode_mode;
uid_t devnode_uid;
gid_t devnode_gid;
char *subsystem;
char *devtype;
char *driver;
char *action;
char *devpath_old;
char *id_filename;
char **envp;
char *monitor_buf;
size_t monitor_buf_len;
struct udev_list devlinks_list;
struct udev_list properties_list;
struct udev_list sysattr_value_list;
struct udev_list sysattr_list;
struct udev_list tags_list;
unsigned long long int seqnum;
usec_t usec_initialized;
int devlink_priority;
int refcount;
dev_t devnum;
int ifindex;
int watch_handle;
int maj, min;
bool parent_set;
bool subsystem_set;
bool devtype_set;
bool devlinks_uptodate;
bool envp_uptodate;
bool tags_uptodate;
bool driver_set;
bool info_loaded;
bool db_loaded;
bool uevent_loaded;
bool is_initialized;
bool sysattr_list_read;
bool db_persist;
};
/**
* udev_device_get_seqnum:
* @udev_device: udev device
*
* This is only valid if the device was received through a monitor. Devices read from
* sys do not have a sequence number.
*
* Returns: the kernel event sequence number, or 0 if there is no sequence number available.
**/
_public_ unsigned long long int udev_device_get_seqnum(struct udev_device *udev_device)
{
if (udev_device == NULL)
return 0;
return udev_device->seqnum;
}
static int udev_device_set_seqnum(struct udev_device *udev_device, unsigned long long int seqnum)
{
char num[32];
udev_device->seqnum = seqnum;
snprintf(num, sizeof(num), "%llu", seqnum);
udev_device_add_property(udev_device, "SEQNUM", num);
return 0;
}
int udev_device_get_ifindex(struct udev_device *udev_device)
{
if (!udev_device->info_loaded)
udev_device_read_uevent_file(udev_device);
return udev_device->ifindex;
}
static int udev_device_set_ifindex(struct udev_device *udev_device, int ifindex)
{
char num[32];
udev_device->ifindex = ifindex;
snprintf(num, sizeof(num), "%u", ifindex);
udev_device_add_property(udev_device, "IFINDEX", num);
return 0;
}
/**
* udev_device_get_devnum:
* @udev_device: udev device
*
* Get the device major/minor number.
*
* Returns: the dev_t number.
**/
_public_ dev_t udev_device_get_devnum(struct udev_device *udev_device)
{
if (udev_device == NULL)
return makedev(0, 0);
if (!udev_device->info_loaded)
udev_device_read_uevent_file(udev_device);
return udev_device->devnum;
}
int udev_device_set_devnum(struct udev_device *udev_device, dev_t devnum)
{
char num[32];
udev_device->devnum = devnum;
snprintf(num, sizeof(num), "%u", major(devnum));
udev_device_add_property(udev_device, "MAJOR", num);
snprintf(num, sizeof(num), "%u", minor(devnum));
udev_device_add_property(udev_device, "MINOR", num);
return 0;
}
const char *udev_device_get_devpath_old(struct udev_device *udev_device)
{
return udev_device->devpath_old;
}
static int udev_device_set_devpath_old(struct udev_device *udev_device, const char *devpath_old)
{
const char *pos;
free(udev_device->devpath_old);
udev_device->devpath_old = strdup(devpath_old);
if (udev_device->devpath_old == NULL)
return -ENOMEM;
udev_device_add_property(udev_device, "DEVPATH_OLD", udev_device->devpath_old);
pos = strrchr(udev_device->devpath_old, '/');
if (pos == NULL)
return -EINVAL;
return 0;
}
/**
* udev_device_get_driver:
* @udev_device: udev device
*
* Get the kernel driver name.
*
* Returns: the driver name string, or #NULL if there is no driver attached.
**/
_public_ const char *udev_device_get_driver(struct udev_device *udev_device)
{
char driver[UTIL_NAME_SIZE];
if (udev_device == NULL)
return NULL;
if (!udev_device->driver_set) {
udev_device->driver_set = true;
if (util_get_sys_core_link_value(udev_device->udev, "driver", udev_device->syspath, driver, sizeof(driver)) > 0)
udev_device->driver = strdup(driver);
}
return udev_device->driver;
}
static int udev_device_set_driver(struct udev_device *udev_device, const char *driver)
{
free(udev_device->driver);
udev_device->driver = strdup(driver);
if (udev_device->driver == NULL)
return -ENOMEM;
udev_device->driver_set = true;
udev_device_add_property(udev_device, "DRIVER", udev_device->driver);
return 0;
}
/**
* udev_device_get_devtype:
* @udev_device: udev device
*
* Retrieve the devtype string of the udev device.
*
* Returns: the devtype name of the udev device, or #NULL if it can not be determined
**/
_public_ const char *udev_device_get_devtype(struct udev_device *udev_device)
{
if (udev_device == NULL)
return NULL;
if (!udev_device->devtype_set) {
udev_device->devtype_set = true;
udev_device_read_uevent_file(udev_device);
}
return udev_device->devtype;
}
static int udev_device_set_devtype(struct udev_device *udev_device, const char *devtype)
{
free(udev_device->devtype);
udev_device->devtype = strdup(devtype);
if (udev_device->devtype == NULL)
return -ENOMEM;
udev_device->devtype_set = true;
udev_device_add_property(udev_device, "DEVTYPE", udev_device->devtype);
return 0;
}
int udev_device_set_subsystem(struct udev_device *udev_device, const char *subsystem)
{
free(udev_device->subsystem);
udev_device->subsystem = strdup(subsystem);
if (udev_device->subsystem == NULL)
return -ENOMEM;
udev_device->subsystem_set = true;
udev_device_add_property(udev_device, "SUBSYSTEM", udev_device->subsystem);
return 0;
}
/**
* udev_device_get_subsystem:
* @udev_device: udev device
*
* Retrieve the subsystem string of the udev device. The string does not
* contain any "/".
*
* Returns: the subsystem name of the udev device, or #NULL if it can not be determined
**/
_public_ const char *udev_device_get_subsystem(struct udev_device *udev_device)
{
char subsystem[UTIL_NAME_SIZE];
if (udev_device == NULL)
return NULL;
if (!udev_device->subsystem_set) {
udev_device->subsystem_set = true;
/* read "subsystem" link */
if (util_get_sys_core_link_value(udev_device->udev, "subsystem", udev_device->syspath, subsystem, sizeof(subsystem)) > 0) {
udev_device_set_subsystem(udev_device, subsystem);
return udev_device->subsystem;
}
/* implicit names */
if (startswith(udev_device->devpath, "/module/")) {
udev_device_set_subsystem(udev_device, "module");
return udev_device->subsystem;
}
if (strstr(udev_device->devpath, "/drivers/") != NULL) {
udev_device_set_subsystem(udev_device, "drivers");
return udev_device->subsystem;
}
if (startswith(udev_device->devpath, "/subsystem/") ||
startswith(udev_device->devpath, "/class/") ||
startswith(udev_device->devpath, "/bus/")) {
udev_device_set_subsystem(udev_device, "subsystem");
return udev_device->subsystem;
}
}
return udev_device->subsystem;
}
mode_t udev_device_get_devnode_mode(struct udev_device *udev_device)
{
if (!udev_device->info_loaded)
udev_device_read_uevent_file(udev_device);
return udev_device->devnode_mode;
}
static int udev_device_set_devnode_mode(struct udev_device *udev_device, mode_t mode)
{
char num[32];
udev_device->devnode_mode = mode;
snprintf(num, sizeof(num), "%#o", mode);
udev_device_add_property(udev_device, "DEVMODE", num);
return 0;
}
uid_t udev_device_get_devnode_uid(struct udev_device *udev_device)
{
if (!udev_device->info_loaded)
udev_device_read_uevent_file(udev_device);
return udev_device->devnode_uid;
}
static int udev_device_set_devnode_uid(struct udev_device *udev_device, uid_t uid)
{
char num[32];
udev_device->devnode_uid = uid;
snprintf(num, sizeof(num), "%u", uid);
udev_device_add_property(udev_device, "DEVUID", num);
return 0;
}
gid_t udev_device_get_devnode_gid(struct udev_device *udev_device)
{
if (!udev_device->info_loaded)
udev_device_read_uevent_file(udev_device);
return udev_device->devnode_gid;
}
static int udev_device_set_devnode_gid(struct udev_device *udev_device, gid_t gid)
{
char num[32];
udev_device->devnode_gid = gid;
snprintf(num, sizeof(num), "%u", gid);
udev_device_add_property(udev_device, "DEVGID", num);
return 0;
}
struct udev_list_entry *udev_device_add_property(struct udev_device *udev_device, const char *key, const char *value)
{
udev_device->envp_uptodate = false;
if (value == NULL) {
struct udev_list_entry *list_entry;
list_entry = udev_device_get_properties_list_entry(udev_device);
list_entry = udev_list_entry_get_by_name(list_entry, key);
if (list_entry != NULL)
udev_list_entry_delete(list_entry);
return NULL;
}
return udev_list_entry_add(&udev_device->properties_list, key, value);
}
static struct udev_list_entry *udev_device_add_property_from_string(struct udev_device *udev_device, const char *property)
{
char name[UTIL_LINE_SIZE];
char *val;
strscpy(name, sizeof(name), property);
val = strchr(name, '=');
if (val == NULL)
return NULL;
val[0] = '\0';
val = &val[1];
if (val[0] == '\0')
val = NULL;
return udev_device_add_property(udev_device, name, val);
}
/*
* parse property string, and if needed, update internal values accordingly
*
* udev_device_add_property_from_string_parse_finish() needs to be
* called after adding properties, and its return value checked
*
* udev_device_set_info_loaded() needs to be set, to avoid trying
* to use a device without a DEVPATH set
*/
void udev_device_add_property_from_string_parse(struct udev_device *udev_device, const char *property)
{
if (startswith(property, "DEVPATH=")) {
char path[UTIL_PATH_SIZE];
strscpyl(path, sizeof(path), "/sys", &property[8], NULL);
udev_device_set_syspath(udev_device, path);
} else if (startswith(property, "SUBSYSTEM=")) {
udev_device_set_subsystem(udev_device, &property[10]);
} else if (startswith(property, "DEVTYPE=")) {
udev_device_set_devtype(udev_device, &property[8]);
} else if (startswith(property, "DEVNAME=")) {
udev_device_set_devnode(udev_device, &property[8]);
} else if (startswith(property, "DEVLINKS=")) {
char devlinks[UTIL_PATH_SIZE];
char *slink;
char *next;
strscpy(devlinks, sizeof(devlinks), &property[9]);
slink = devlinks;
next = strchr(slink, ' ');
while (next != NULL) {
next[0] = '\0';
udev_device_add_devlink(udev_device, slink);
slink = &next[1];
next = strchr(slink, ' ');
}
if (slink[0] != '\0')
udev_device_add_devlink(udev_device, slink);
} else if (startswith(property, "TAGS=")) {
char tags[UTIL_PATH_SIZE];
char *next;
strscpy(tags, sizeof(tags), &property[5]);
next = strchr(tags, ':');
if (next != NULL) {
next++;
while (next[0] != '\0') {
char *tag;
tag = next;
next = strchr(tag, ':');
if (next == NULL)
break;
next[0] = '\0';
next++;
udev_device_add_tag(udev_device, tag);
}
}
} else if (startswith(property, "USEC_INITIALIZED=")) {
udev_device_set_usec_initialized(udev_device, strtoull(&property[19], NULL, 10));
} else if (startswith(property, "DRIVER=")) {
udev_device_set_driver(udev_device, &property[7]);
} else if (startswith(property, "ACTION=")) {
udev_device_set_action(udev_device, &property[7]);
} else if (startswith(property, "MAJOR=")) {
udev_device->maj = strtoull(&property[6], NULL, 10);
} else if (startswith(property, "MINOR=")) {
udev_device->min = strtoull(&property[6], NULL, 10);
} else if (startswith(property, "DEVPATH_OLD=")) {
udev_device_set_devpath_old(udev_device, &property[12]);
} else if (startswith(property, "SEQNUM=")) {
udev_device_set_seqnum(udev_device, strtoull(&property[7], NULL, 10));
} else if (startswith(property, "IFINDEX=")) {
udev_device_set_ifindex(udev_device, strtoull(&property[8], NULL, 10));
} else if (startswith(property, "DEVMODE=")) {
udev_device_set_devnode_mode(udev_device, strtoul(&property[8], NULL, 8));
} else if (startswith(property, "DEVUID=")) {
udev_device_set_devnode_uid(udev_device, strtoul(&property[7], NULL, 10));
} else if (startswith(property, "DEVGID=")) {
udev_device_set_devnode_gid(udev_device, strtoul(&property[7], NULL, 10));
} else {
udev_device_add_property_from_string(udev_device, property);
}
}
int udev_device_add_property_from_string_parse_finish(struct udev_device *udev_device)
{
if (udev_device->maj > 0)
udev_device_set_devnum(udev_device, makedev(udev_device->maj, udev_device->min));
udev_device->maj = 0;
udev_device->min = 0;
if (udev_device->devpath == NULL || udev_device->subsystem == NULL)
return -EINVAL;
return 0;
}
/**
* udev_device_get_property_value:
* @udev_device: udev device
* @key: property name
*
* Get the value of a given property.
*
* Returns: the property string, or #NULL if there is no such property.
**/
_public_ const char *udev_device_get_property_value(struct udev_device *udev_device, const char *key)
{
struct udev_list_entry *list_entry;
if (udev_device == NULL)
return NULL;
if (key == NULL)
return NULL;
list_entry = udev_device_get_properties_list_entry(udev_device);
list_entry = udev_list_entry_get_by_name(list_entry, key);
return udev_list_entry_get_value(list_entry);
}
int udev_device_read_db(struct udev_device *udev_device, const char *dbfile)
{
char filename[UTIL_PATH_SIZE];
char line[UTIL_LINE_SIZE];
FILE *f;
/* providing a database file will always force-load it */
if (dbfile == NULL) {
const char *id;
if (udev_device->db_loaded)
return 0;
udev_device->db_loaded = true;
id = udev_device_get_id_filename(udev_device);
if (id == NULL)
return -1;
strscpyl(filename, sizeof(filename), "/run/udev/data/", id, NULL);
dbfile = filename;
}
f = fopen(dbfile, "re");
if (f == NULL) {
udev_dbg(udev_device->udev, "no db file to read %s: %m\n", dbfile);
return -errno;
}
/* devices with a database entry are initialized */
udev_device->is_initialized = true;
while (fgets(line, sizeof(line), f)) {
ssize_t len;
const char *val;
struct udev_list_entry *entry;
len = strlen(line);
if (len < 4)
break;
line[len-1] = '\0';
val = &line[2];
switch(line[0]) {
case 'S':
strscpyl(filename, sizeof(filename), "/dev/", val, NULL);
udev_device_add_devlink(udev_device, filename);
break;
case 'L':
udev_device_set_devlink_priority(udev_device, atoi(val));
break;
case 'E':
entry = udev_device_add_property_from_string(udev_device, val);
udev_list_entry_set_num(entry, true);
break;
case 'G':
udev_device_add_tag(udev_device, val);
break;
case 'W':
udev_device_set_watch_handle(udev_device, atoi(val));
break;
case 'I':
udev_device_set_usec_initialized(udev_device, strtoull(val, NULL, 10));
break;
}
}
fclose(f);
udev_dbg(udev_device->udev, "device %p filled with db file data\n", udev_device);
return 0;
}
int udev_device_read_uevent_file(struct udev_device *udev_device)
{
char filename[UTIL_PATH_SIZE];
FILE *f;
char line[UTIL_LINE_SIZE];
int maj = 0;
int min = 0;
if (udev_device->uevent_loaded)
return 0;
strscpyl(filename, sizeof(filename), udev_device->syspath, "/uevent", NULL);
f = fopen(filename, "re");
if (f == NULL)
return -errno;
udev_device->uevent_loaded = true;
while (fgets(line, sizeof(line), f)) {
char *pos;
pos = strchr(line, '\n');
if (pos == NULL)
continue;
pos[0] = '\0';
if (startswith(line, "DEVTYPE=")) {
udev_device_set_devtype(udev_device, &line[8]);
continue;
}
if (startswith(line, "IFINDEX=")) {
udev_device_set_ifindex(udev_device, strtoull(&line[8], NULL, 10));
continue;
}
if (startswith(line, "DEVNAME=")) {
udev_device_set_devnode(udev_device, &line[8]);
continue;
}
if (startswith(line, "MAJOR="))
maj = strtoull(&line[6], NULL, 10);
else if (startswith(line, "MINOR="))
min = strtoull(&line[6], NULL, 10);
else if (startswith(line, "DEVMODE="))
udev_device->devnode_mode = strtoul(&line[8], NULL, 8);
udev_device_add_property_from_string(udev_device, line);
}
udev_device->devnum = makedev(maj, min);
fclose(f);
return 0;
}
void udev_device_set_info_loaded(struct udev_device *device)
{
device->info_loaded = true;
}
struct udev_device *udev_device_new(struct udev *udev)
{
struct udev_device *udev_device;
struct udev_list_entry *list_entry;
if (udev == NULL) {
errno = EINVAL;
return NULL;
}
udev_device = new0(struct udev_device, 1);
if (udev_device == NULL) {
errno = ENOMEM;
return NULL;
}
udev_device->refcount = 1;
udev_device->udev = udev;
udev_list_init(udev, &udev_device->devlinks_list, true);
udev_list_init(udev, &udev_device->properties_list, true);
udev_list_init(udev, &udev_device->sysattr_value_list, true);
udev_list_init(udev, &udev_device->sysattr_list, false);
udev_list_init(udev, &udev_device->tags_list, true);
udev_device->watch_handle = -1;
/* copy global properties */
udev_list_entry_foreach(list_entry, udev_get_properties_list_entry(udev))
udev_device_add_property(udev_device,
udev_list_entry_get_name(list_entry),
udev_list_entry_get_value(list_entry));
return udev_device;
}
/**
* udev_device_new_from_syspath:
* @udev: udev library context
* @syspath: sys device path including sys directory
*
* Create new udev device, and fill in information from the sys
* device and the udev database entry. The syspath is the absolute
* path to the device, including the sys mount point.
*
* The initial refcount is 1, and needs to be decremented to
* release the resources of the udev device.
*
* Returns: a new udev device, or #NULL, if it does not exist
**/
_public_ struct udev_device *udev_device_new_from_syspath(struct udev *udev, const char *syspath)
{
const char *subdir;
char path[UTIL_PATH_SIZE];
char *pos;
struct stat statbuf;
struct udev_device *udev_device;
if (udev == NULL) {
errno = EINVAL;
return NULL;
}
if (syspath == NULL) {
errno = EINVAL;
return NULL;
}
/* path starts in sys */
if (!startswith(syspath, "/sys")) {
udev_dbg(udev, "not in sys :%s\n", syspath);
errno = EINVAL;
return NULL;
}
/* path is not a root directory */
subdir = syspath + strlen("/sys");
pos = strrchr(subdir, '/');
if (pos == NULL || pos[1] == '\0' || pos < &subdir[2]) {
errno = EINVAL;
return NULL;
}
/* resolve possible symlink to real path */
strscpy(path, sizeof(path), syspath);
util_resolve_sys_link(udev, path, sizeof(path));
if (startswith(path + strlen("/sys"), "/devices/")) {
char file[UTIL_PATH_SIZE];
/* all "devices" require a "uevent" file */
strscpyl(file, sizeof(file), path, "/uevent", NULL);
if (stat(file, &statbuf) != 0)
return NULL;
} else {
/* everything else just needs to be a directory */
if (stat(path, &statbuf) != 0 || !S_ISDIR(statbuf.st_mode))
return NULL;
}
udev_device = udev_device_new(udev);
if (udev_device == NULL)
return NULL;
udev_device_set_syspath(udev_device, path);
udev_dbg(udev, "device %p has devpath '%s'\n", udev_device, udev_device_get_devpath(udev_device));
return udev_device;
}
/**
* udev_device_new_from_devnum:
* @udev: udev library context
* @type: char or block device
* @devnum: device major/minor number
*
* Create new udev device, and fill in information from the sys
* device and the udev database entry. The device is looked-up
* by its major/minor number and type. Character and block device
* numbers are not unique across the two types.
*
* The initial refcount is 1, and needs to be decremented to
* release the resources of the udev device.
*
* Returns: a new udev device, or #NULL, if it does not exist
**/
_public_ struct udev_device *udev_device_new_from_devnum(struct udev *udev, char type, dev_t devnum)
{
char path[UTIL_PATH_SIZE];
const char *type_str;
if (type == 'b')
type_str = "block";
else if (type == 'c')
type_str = "char";
else {
errno = EINVAL;
return NULL;
}
/* use /sys/dev/{block,char}/<maj>:<min> link */
snprintf(path, sizeof(path), "/sys/dev/%s/%u:%u",
type_str, major(devnum), minor(devnum));
return udev_device_new_from_syspath(udev, path);
}
/**
* udev_device_new_from_device_id:
* @udev: udev library context
* @id: text string identifying a kernel device
*
* Create new udev device, and fill in information from the sys
* device and the udev database entry. The device is looked-up
* by a special string:
* b8:2 - block device major:minor
* c128:1 - char device major:minor
* n3 - network device ifindex
* +sound:card29 - kernel driver core subsystem:device name
*
* The initial refcount is 1, and needs to be decremented to
* release the resources of the udev device.
*
* Returns: a new udev device, or #NULL, if it does not exist
**/
_public_ struct udev_device *udev_device_new_from_device_id(struct udev *udev, const char *id)
{
char type;
int maj, min;
char subsys[UTIL_PATH_SIZE];
char *sysname;
switch(id[0]) {
case 'b':
case 'c':
if (sscanf(id, "%c%i:%i", &type, &maj, &min) != 3)
return NULL;
return udev_device_new_from_devnum(udev, type, makedev(maj, min));
case 'n': {
int sk;
struct ifreq ifr;
struct udev_device *dev;
int ifindex;
ifindex = strtoul(&id[1], NULL, 10);
if (ifindex <= 0) {
errno = EINVAL;
return NULL;
}
sk = socket(PF_INET, SOCK_DGRAM, 0);
if (sk < 0)
return NULL;
memzero(&ifr, sizeof(struct ifreq));
ifr.ifr_ifindex = ifindex;
if (ioctl(sk, SIOCGIFNAME, &ifr) != 0) {
close(sk);
return NULL;
}
close(sk);
dev = udev_device_new_from_subsystem_sysname(udev, "net", ifr.ifr_name);
if (dev == NULL)
return NULL;
if (udev_device_get_ifindex(dev) == ifindex)
return dev;
/* this is racy, so we may end up with the wrong device */
udev_device_unref(dev);
errno = ENODEV;
return NULL;
}
case '+':
strscpy(subsys, sizeof(subsys), &id[1]);
sysname = strchr(subsys, ':');
if (sysname == NULL) {
errno = EINVAL;
return NULL;
}
sysname[0] = '\0';
sysname = &sysname[1];
return udev_device_new_from_subsystem_sysname(udev, subsys, sysname);
default:
errno = EINVAL;
return NULL;
}
}
/**
* udev_device_new_from_subsystem_sysname:
* @udev: udev library context
* @subsystem: the subsystem of the device
* @sysname: the name of the device
*
* Create new udev device, and fill in information from the sys device
* and the udev database entry. The device is looked up by the subsystem
* and name string of the device, like "mem" / "zero", or "block" / "sda".
*
* The initial refcount is 1, and needs to be decremented to
* release the resources of the udev device.
*
* Returns: a new udev device, or #NULL, if it does not exist
**/
_public_ struct udev_device *udev_device_new_from_subsystem_sysname(struct udev *udev, const char *subsystem, const char *sysname)
{
char path[UTIL_PATH_SIZE];
struct stat statbuf;
if (streq(subsystem, "subsystem")) {
strscpyl(path, sizeof(path), "/sys/subsystem/", sysname, NULL);
if (stat(path, &statbuf) == 0)
goto found;
strscpyl(path, sizeof(path), "/sys/bus/", sysname, NULL);
if (stat(path, &statbuf) == 0)
goto found;
strscpyl(path, sizeof(path), "/sys/class/", sysname, NULL);
if (stat(path, &statbuf) == 0)
goto found;
goto out;
}
if (streq(subsystem, "module")) {
strscpyl(path, sizeof(path), "/sys/module/", sysname, NULL);
if (stat(path, &statbuf) == 0)
goto found;
goto out;
}
if (streq(subsystem, "drivers")) {
char subsys[UTIL_NAME_SIZE];
char *driver;
strscpy(subsys, sizeof(subsys), sysname);
driver = strchr(subsys, ':');
if (driver != NULL) {
driver[0] = '\0';
driver = &driver[1];
strscpyl(path, sizeof(path), "/sys/subsystem/", subsys, "/drivers/", driver, NULL);
if (stat(path, &statbuf) == 0)
goto found;
strscpyl(path, sizeof(path), "/sys/bus/", subsys, "/drivers/", driver, NULL);
if (stat(path, &statbuf) == 0)
goto found;
} else
errno = EINVAL;
goto out;
}
strscpyl(path, sizeof(path), "/sys/subsystem/", subsystem, "/devices/", sysname, NULL);
if (stat(path, &statbuf) == 0)
goto found;
strscpyl(path, sizeof(path), "/sys/bus/", subsystem, "/devices/", sysname, NULL);
if (stat(path, &statbuf) == 0)
goto found;
strscpyl(path, sizeof(path), "/sys/class/", subsystem, "/", sysname, NULL);
if (stat(path, &statbuf) == 0)
goto found;
out:
return NULL;
found:
return udev_device_new_from_syspath(udev, path);
}
/**
* udev_device_new_from_environment
* @udev: udev library context
*
* Create new udev device, and fill in information from the
* current process environment. This only works reliable if
* the process is called from a udev rule. It is usually used
* for tools executed from IMPORT= rules.
*
* The initial refcount is 1, and needs to be decremented to
* release the resources of the udev device.
*
* Returns: a new udev device, or #NULL, if it does not exist
**/
_public_ struct udev_device *udev_device_new_from_environment(struct udev *udev)
{
int i;
struct udev_device *udev_device;
udev_device = udev_device_new(udev);
if (udev_device == NULL)
return NULL;
udev_device_set_info_loaded(udev_device);
for (i = 0; environ[i] != NULL; i++)
udev_device_add_property_from_string_parse(udev_device, environ[i]);
if (udev_device_add_property_from_string_parse_finish(udev_device) < 0) {
udev_dbg(udev, "missing values, invalid device\n");
udev_device_unref(udev_device);
udev_device = NULL;
}
return udev_device;
}
static struct udev_device *device_new_from_parent(struct udev_device *udev_device)
{
struct udev_device *udev_device_parent = NULL;
char path[UTIL_PATH_SIZE];
const char *subdir;
strscpy(path, sizeof(path), udev_device->syspath);
subdir = path + strlen("/sys/");
for (;;) {
char *pos;
pos = strrchr(subdir, '/');
if (pos == NULL || pos < &subdir[2])
break;
pos[0] = '\0';
udev_device_parent = udev_device_new_from_syspath(udev_device->udev, path);
if (udev_device_parent != NULL)
return udev_device_parent;
}
errno = ENOENT;
return NULL;
}
/**
* udev_device_get_parent:
* @udev_device: the device to start searching from
*
* Find the next parent device, and fill in information from the sys
* device and the udev database entry.
*
* Returned device is not referenced. It is attached to the child
* device, and will be cleaned up when the child device is cleaned up.
*
* It is not necessarily just the upper level directory, empty or not
* recognized sys directories are ignored.
*
* It can be called as many times as needed, without caring about
* references.
*
* Returns: a new udev device, or #NULL, if it no parent exist.
**/
_public_ struct udev_device *udev_device_get_parent(struct udev_device *udev_device)
{
if (udev_device == NULL) {
errno = EINVAL;
return NULL;
}
if (!udev_device->parent_set) {
udev_device->parent_set = true;
udev_device->parent_device = device_new_from_parent(udev_device);
}
return udev_device->parent_device;
}
/**
* udev_device_get_parent_with_subsystem_devtype:
* @udev_device: udev device to start searching from
* @subsystem: the subsystem of the device
* @devtype: the type (DEVTYPE) of the device
*
* Find the next parent device, with a matching subsystem and devtype
* value, and fill in information from the sys device and the udev
* database entry.
*
* If devtype is #NULL, only subsystem is checked, and any devtype will
* match.
*
* Returned device is not referenced. It is attached to the child
* device, and will be cleaned up when the child device is cleaned up.
*
* It can be called as many times as needed, without caring about
* references.
*
* Returns: a new udev device, or #NULL if no matching parent exists.
**/
_public_ struct udev_device *udev_device_get_parent_with_subsystem_devtype(struct udev_device *udev_device, const char *subsystem, const char *devtype)
{
struct udev_device *parent;
if (subsystem == NULL) {
errno = EINVAL;
return NULL;
}
parent = udev_device_get_parent(udev_device);
while (parent != NULL) {
const char *parent_subsystem;
const char *parent_devtype;
parent_subsystem = udev_device_get_subsystem(parent);
if (parent_subsystem != NULL && streq(parent_subsystem, subsystem)) {
if (devtype == NULL)
break;
parent_devtype = udev_device_get_devtype(parent);
if (parent_devtype != NULL && streq(parent_devtype, devtype))
break;
}
parent = udev_device_get_parent(parent);
}
if (!parent)
errno = ENOENT;
return parent;
}
/**
* udev_device_get_udev:
* @udev_device: udev device
*
* Retrieve the udev library context the device was created with.
*
* Returns: the udev library context
**/
_public_ struct udev *udev_device_get_udev(struct udev_device *udev_device)
{
if (udev_device == NULL)
return NULL;
return udev_device->udev;
}
/**
* udev_device_ref:
* @udev_device: udev device
*
* Take a reference of a udev device.
*
* Returns: the passed udev device
**/
_public_ struct udev_device *udev_device_ref(struct udev_device *udev_device)
{
if (udev_device == NULL)
return NULL;
udev_device->refcount++;
return udev_device;
}
/**
* udev_device_unref:
* @udev_device: udev device
*
* Drop a reference of a udev device. If the refcount reaches zero,
* the resources of the device will be released.
*
* Returns: #NULL
**/
_public_ struct udev_device *udev_device_unref(struct udev_device *udev_device)
{
if (udev_device == NULL)
return NULL;
udev_device->refcount--;
if (udev_device->refcount > 0)
return NULL;
if (udev_device->parent_device != NULL)
udev_device_unref(udev_device->parent_device);
free(udev_device->syspath);
free(udev_device->sysname);
free(udev_device->devnode);
free(udev_device->subsystem);
free(udev_device->devtype);
udev_list_cleanup(&udev_device->devlinks_list);
udev_list_cleanup(&udev_device->properties_list);
udev_list_cleanup(&udev_device->sysattr_value_list);
udev_list_cleanup(&udev_device->sysattr_list);
udev_list_cleanup(&udev_device->tags_list);
free(udev_device->action);
free(udev_device->driver);
free(udev_device->devpath_old);
free(udev_device->id_filename);
free(udev_device->envp);
free(udev_device->monitor_buf);
free(udev_device);
return NULL;
}
/**
* udev_device_get_devpath:
* @udev_device: udev device
*
* Retrieve the kernel devpath value of the udev device. The path
* does not contain the sys mount point, and starts with a '/'.
*
* Returns: the devpath of the udev device
**/
_public_ const char *udev_device_get_devpath(struct udev_device *udev_device)
{
if (udev_device == NULL)
return NULL;
return udev_device->devpath;
}
/**
* udev_device_get_syspath:
* @udev_device: udev device
*
* Retrieve the sys path of the udev device. The path is an
* absolute path and starts with the sys mount point.
*
* Returns: the sys path of the udev device
**/
_public_ const char *udev_device_get_syspath(struct udev_device *udev_device)
{
if (udev_device == NULL)
return NULL;
return udev_device->syspath;
}
/**
* udev_device_get_sysname:
* @udev_device: udev device
*
* Get the kernel device name in /sys.
*
* Returns: the name string of the device device
**/
_public_ const char *udev_device_get_sysname(struct udev_device *udev_device)
{
if (udev_device == NULL)
return NULL;
return udev_device->sysname;
}
/**
* udev_device_get_sysnum:
* @udev_device: udev device
*
* Get the instance number of the device.
*
* Returns: the trailing number string of the device name
**/
_public_ const char *udev_device_get_sysnum(struct udev_device *udev_device)
{
if (udev_device == NULL)
return NULL;
return udev_device->sysnum;
}
/**
* udev_device_get_devnode:
* @udev_device: udev device
*
* Retrieve the device node file name belonging to the udev device.
* The path is an absolute path, and starts with the device directory.
*
* Returns: the device node file name of the udev device, or #NULL if no device node exists
**/
_public_ const char *udev_device_get_devnode(struct udev_device *udev_device)
{
if (udev_device == NULL)
return NULL;
if (udev_device->devnode != NULL)
return udev_device->devnode;
if (!udev_device->info_loaded)
udev_device_read_uevent_file(udev_device);
return udev_device->devnode;
}
/**
* udev_device_get_devlinks_list_entry:
* @udev_device: udev device
*
* Retrieve the list of device links pointing to the device file of
* the udev device. The next list entry can be retrieved with
* udev_list_entry_get_next(), which returns #NULL if no more entries exist.
* The devlink path can be retrieved from the list entry by
* udev_list_entry_get_name(). The path is an absolute path, and starts with
* the device directory.
*
* Returns: the first entry of the device node link list
**/
_public_ struct udev_list_entry *udev_device_get_devlinks_list_entry(struct udev_device *udev_device)
{
if (udev_device == NULL)
return NULL;
if (!udev_device->info_loaded)
udev_device_read_db(udev_device, NULL);
return udev_list_get_entry(&udev_device->devlinks_list);
}
void udev_device_cleanup_devlinks_list(struct udev_device *udev_device)
{
udev_device->devlinks_uptodate = false;
udev_list_cleanup(&udev_device->devlinks_list);
}
/**
* udev_device_get_properties_list_entry:
* @udev_device: udev device
*
* Retrieve the list of key/value device properties of the udev
* device. The next list entry can be retrieved with udev_list_entry_get_next(),
* which returns #NULL if no more entries exist. The property name
* can be retrieved from the list entry by udev_list_entry_get_name(),
* the property value by udev_list_entry_get_value().
*
* Returns: the first entry of the property list
**/
_public_ struct udev_list_entry *udev_device_get_properties_list_entry(struct udev_device *udev_device)
{
if (udev_device == NULL)
return NULL;
if (!udev_device->info_loaded) {
udev_device_read_uevent_file(udev_device);
udev_device_read_db(udev_device, NULL);
}
if (!udev_device->devlinks_uptodate) {
char symlinks[UTIL_PATH_SIZE];
struct udev_list_entry *list_entry;
udev_device->devlinks_uptodate = true;
list_entry = udev_device_get_devlinks_list_entry(udev_device);
if (list_entry != NULL) {
char *s;
size_t l;
s = symlinks;
l = strpcpyl(&s, sizeof(symlinks), udev_list_entry_get_name(list_entry), NULL);
udev_list_entry_foreach(list_entry, udev_list_entry_get_next(list_entry))
l = strpcpyl(&s, l, " ", udev_list_entry_get_name(list_entry), NULL);
udev_device_add_property(udev_device, "DEVLINKS", symlinks);
}
}
if (!udev_device->tags_uptodate) {
udev_device->tags_uptodate = true;
if (udev_device_get_tags_list_entry(udev_device) != NULL) {
char tags[UTIL_PATH_SIZE];
struct udev_list_entry *list_entry;
char *s;
size_t l;
s = tags;
l = strpcpyl(&s, sizeof(tags), ":", NULL);
udev_list_entry_foreach(list_entry, udev_device_get_tags_list_entry(udev_device))
l = strpcpyl(&s, l, udev_list_entry_get_name(list_entry), ":", NULL);
udev_device_add_property(udev_device, "TAGS", tags);
}
}
return udev_list_get_entry(&udev_device->properties_list);
}
/**
* udev_device_get_action:
* @udev_device: udev device
*
* This is only valid if the device was received through a monitor. Devices read from
* sys do not have an action string. Usual actions are: add, remove, change, online,
* offline.
*
* Returns: the kernel action value, or #NULL if there is no action value available.
**/
_public_ const char *udev_device_get_action(struct udev_device *udev_device)
{
if (udev_device == NULL)
return NULL;
return udev_device->action;
}
/**
* udev_device_get_usec_since_initialized:
* @udev_device: udev device
*
* Return the number of microseconds passed since udev set up the
* device for the first time.
*
* This is only implemented for devices with need to store properties
* in the udev database. All other devices return 0 here.
*
* Returns: the number of microseconds since the device was first seen.
**/
_public_ unsigned long long int udev_device_get_usec_since_initialized(struct udev_device *udev_device)
{
usec_t now_ts;
if (udev_device == NULL)
return 0;
if (!udev_device->info_loaded)
udev_device_read_db(udev_device, NULL);
if (udev_device->usec_initialized == 0)
return 0;
now_ts = now(CLOCK_MONOTONIC);
if (now_ts == 0)
return 0;
return now_ts - udev_device->usec_initialized;
}
usec_t udev_device_get_usec_initialized(struct udev_device *udev_device)
{
return udev_device->usec_initialized;
}
void udev_device_set_usec_initialized(struct udev_device *udev_device, usec_t usec_initialized)
{
char num[32];
udev_device->usec_initialized = usec_initialized;
snprintf(num, sizeof(num), USEC_FMT, usec_initialized);
udev_device_add_property(udev_device, "USEC_INITIALIZED", num);
}
/**
* udev_device_get_sysattr_value:
* @udev_device: udev device
* @sysattr: attribute name
*
* The retrieved value is cached in the device. Repeated calls will return the same
* value and not open the attribute again.
*
* Returns: the content of a sys attribute file, or #NULL if there is no sys attribute value.
**/
_public_ const char *udev_device_get_sysattr_value(struct udev_device *udev_device, const char *sysattr)
{
struct udev_list_entry *list_entry;
char path[UTIL_PATH_SIZE];
char value[4096];
struct stat statbuf;
int fd;
ssize_t size;
const char *val = NULL;
if (udev_device == NULL)
return NULL;
if (sysattr == NULL)
return NULL;
/* look for possibly already cached result */
list_entry = udev_list_get_entry(&udev_device->sysattr_value_list);
list_entry = udev_list_entry_get_by_name(list_entry, sysattr);
if (list_entry != NULL)
return udev_list_entry_get_value(list_entry);
strscpyl(path, sizeof(path), udev_device_get_syspath(udev_device), "/", sysattr, NULL);
if (lstat(path, &statbuf) != 0) {
udev_list_entry_add(&udev_device->sysattr_value_list, sysattr, NULL);
goto out;
}
if (S_ISLNK(statbuf.st_mode)) {
/*
* Some core links return only the last element of the target path,
* these are just values, the paths should not be exposed.
*/
if (streq(sysattr, "driver") ||
streq(sysattr, "subsystem") ||
streq(sysattr, "module")) {
if (util_get_sys_core_link_value(udev_device->udev, sysattr,
udev_device->syspath, value, sizeof(value)) < 0)
return NULL;
list_entry = udev_list_entry_add(&udev_device->sysattr_value_list, sysattr, value);
val = udev_list_entry_get_value(list_entry);
goto out;
}
goto out;
}
/* skip directories */
if (S_ISDIR(statbuf.st_mode))
goto out;
/* skip non-readable files */
if ((statbuf.st_mode & S_IRUSR) == 0)
goto out;
/* read attribute value */
fd = open(path, O_RDONLY|O_CLOEXEC);
if (fd < 0)
goto out;
size = read(fd, value, sizeof(value));
close(fd);
if (size < 0)
goto out;
if (size == sizeof(value))
goto out;
/* got a valid value, store it in cache and return it */
value[size] = '\0';
util_remove_trailing_chars(value, '\n');
list_entry = udev_list_entry_add(&udev_device->sysattr_value_list, sysattr, value);
val = udev_list_entry_get_value(list_entry);
out:
return val;
}
/**
* udev_device_set_sysattr_value:
* @udev_device: udev device
* @sysattr: attribute name
* @value: new value to be set
*
* Update the contents of the sys attribute and the cached value of the device.
*
* Returns: Negative error code on failure or 0 on success.
**/
_public_ int udev_device_set_sysattr_value(struct udev_device *udev_device, const char *sysattr, char *value)
{
struct udev_device *dev;
char path[UTIL_PATH_SIZE];
struct stat statbuf;
int fd;
ssize_t size, value_len;
int ret = 0;
if (udev_device == NULL)
return -EINVAL;
dev = udev_device;
if (sysattr == NULL)
return -EINVAL;
if (value == NULL)
value_len = 0;
else
value_len = strlen(value);
strscpyl(path, sizeof(path), udev_device_get_syspath(dev), "/", sysattr, NULL);
if (lstat(path, &statbuf) != 0) {
udev_list_entry_add(&dev->sysattr_value_list, sysattr, NULL);
ret = -ENXIO;
goto out;
}
if (S_ISLNK(statbuf.st_mode)) {
ret = -EINVAL;
goto out;
}
/* skip directories */
if (S_ISDIR(statbuf.st_mode)) {
ret = -EISDIR;
goto out;
}
/* skip non-readable files */
if ((statbuf.st_mode & S_IRUSR) == 0) {
ret = -EACCES;
goto out;
}
/* Value is limited to 4k */
if (value_len > 4096) {
ret = -EINVAL;
goto out;
}
util_remove_trailing_chars(value, '\n');
/* write attribute value */
fd = open(path, O_WRONLY|O_CLOEXEC);
if (fd < 0) {
ret = -errno;
goto out;
}
size = write(fd, value, value_len);
close(fd);
if (size < 0) {
ret = -errno;
goto out;
}
if (size < value_len) {
ret = -EIO;
goto out;
}
/* wrote a valid value, store it in cache and return it */
udev_list_entry_add(&dev->sysattr_value_list, sysattr, value);
out:
if (dev != udev_device)
udev_device_unref(dev);
return ret;
}
static int udev_device_sysattr_list_read(struct udev_device *udev_device)
{
struct dirent *dent;
DIR *dir;
int num = 0;
if (udev_device == NULL)
return -EINVAL;
if (udev_device->sysattr_list_read)
return 0;
dir = opendir(udev_device_get_syspath(udev_device));
if (!dir)
return -errno;
for (dent = readdir(dir); dent != NULL; dent = readdir(dir)) {
char path[UTIL_PATH_SIZE];
struct stat statbuf;
/* only handle symlinks and regular files */
if (dent->d_type != DT_LNK && dent->d_type != DT_REG)
continue;
strscpyl(path, sizeof(path), udev_device_get_syspath(udev_device), "/", dent->d_name, NULL);
if (lstat(path, &statbuf) != 0)
continue;
if ((statbuf.st_mode & S_IRUSR) == 0)
continue;
udev_list_entry_add(&udev_device->sysattr_list, dent->d_name, NULL);
num++;
}
closedir(dir);
udev_device->sysattr_list_read = true;
return num;
}
/**
* udev_device_get_sysattr_list_entry:
* @udev_device: udev device
*
* Retrieve the list of available sysattrs, with value being empty;
* This just return all available sysfs attributes for a particular
* device without reading their values.
*
* Returns: the first entry of the property list
**/
_public_ struct udev_list_entry *udev_device_get_sysattr_list_entry(struct udev_device *udev_device)
{
if (!udev_device->sysattr_list_read) {
int ret;
ret = udev_device_sysattr_list_read(udev_device);
if (0 > ret)
return NULL;
}
return udev_list_get_entry(&udev_device->sysattr_list);
}
int udev_device_set_syspath(struct udev_device *udev_device, const char *syspath)
{
const char *pos;
size_t len;
free(udev_device->syspath);
udev_device->syspath = strdup(syspath);
if (udev_device->syspath == NULL)
return -ENOMEM;
udev_device->devpath = udev_device->syspath + strlen("/sys");
udev_device_add_property(udev_device, "DEVPATH", udev_device->devpath);
pos = strrchr(udev_device->syspath, '/');
if (pos == NULL)
return -EINVAL;
udev_device->sysname = strdup(&pos[1]);
if (udev_device->sysname == NULL)
return -ENOMEM;
/* some devices have '!' in their name, change that to '/' */
len = 0;
while (udev_device->sysname[len] != '\0') {
if (udev_device->sysname[len] == '!')
udev_device->sysname[len] = '/';
len++;
}
/* trailing number */
while (len > 0 && isdigit(udev_device->sysname[--len]))
udev_device->sysnum = &udev_device->sysname[len];
/* sysname is completely numeric */
if (len == 0)
udev_device->sysnum = NULL;
return 0;
}
static int udev_device_set_devnode(struct udev_device *udev_device, const char *devnode)
{
free(udev_device->devnode);
if (devnode[0] != '/') {
if (asprintf(&udev_device->devnode, "/dev/%s", devnode) < 0)
udev_device->devnode = NULL;
} else {
udev_device->devnode = strdup(devnode);
}
if (udev_device->devnode == NULL)
return -ENOMEM;
udev_device_add_property(udev_device, "DEVNAME", udev_device->devnode);
return 0;
}
int udev_device_add_devlink(struct udev_device *udev_device, const char *devlink)
{
struct udev_list_entry *list_entry;
udev_device->devlinks_uptodate = false;
list_entry = udev_list_entry_add(&udev_device->devlinks_list, devlink, NULL);
if (list_entry == NULL)
return -ENOMEM;
return 0;
}
const char *udev_device_get_id_filename(struct udev_device *udev_device)
{
if (udev_device->id_filename == NULL) {
if (udev_device_get_subsystem(udev_device) == NULL)
return NULL;
if (major(udev_device_get_devnum(udev_device)) > 0) {
/* use dev_t -- b259:131072, c254:0 */
if (asprintf(&udev_device->id_filename, "%c%u:%u",
streq(udev_device_get_subsystem(udev_device), "block") ? 'b' : 'c',
major(udev_device_get_devnum(udev_device)),
minor(udev_device_get_devnum(udev_device))) < 0)
udev_device->id_filename = NULL;
} else if (udev_device_get_ifindex(udev_device) > 0) {
/* use netdev ifindex -- n3 */
if (asprintf(&udev_device->id_filename, "n%u", udev_device_get_ifindex(udev_device)) < 0)
udev_device->id_filename = NULL;
} else {
/*
* use $subsys:$syname -- pci:0000:00:1f.2
* sysname() has '!' translated, get it from devpath
*/
const char *sysname;
sysname = strrchr(udev_device->devpath, '/');
if (sysname == NULL)
return NULL;
sysname = &sysname[1];
if (asprintf(&udev_device->id_filename, "+%s:%s", udev_device_get_subsystem(udev_device), sysname) < 0)
udev_device->id_filename = NULL;
}
}
return udev_device->id_filename;
}
/**
* udev_device_get_is_initialized:
* @udev_device: udev device
*
* Check if udev has already handled the device and has set up
* device node permissions and context, or has renamed a network
* device.
*
* This is only implemented for devices with a device node
* or network interfaces. All other devices return 1 here.
*
* Returns: 1 if the device is set up. 0 otherwise.
**/
_public_ int udev_device_get_is_initialized(struct udev_device *udev_device)
{
if (!udev_device->info_loaded)
udev_device_read_db(udev_device, NULL);
return udev_device->is_initialized;
}
void udev_device_set_is_initialized(struct udev_device *udev_device)
{
udev_device->is_initialized = true;
}
static bool is_valid_tag(const char *tag)
{
return !strchr(tag, ':') && !strchr(tag, ' ');
}
int udev_device_add_tag(struct udev_device *udev_device, const char *tag)
{
if (!is_valid_tag(tag))
return -EINVAL;
udev_device->tags_uptodate = false;
if (udev_list_entry_add(&udev_device->tags_list, tag, NULL) != NULL)
return 0;
return -ENOMEM;
}
void udev_device_remove_tag(struct udev_device *udev_device, const char *tag)
{
struct udev_list_entry *e;
if (!is_valid_tag(tag))
return;
e = udev_list_get_entry(&udev_device->tags_list);
e = udev_list_entry_get_by_name(e, tag);
if (e) {
udev_device->tags_uptodate = false;
udev_list_entry_delete(e);
}
}
void udev_device_cleanup_tags_list(struct udev_device *udev_device)
{
udev_device->tags_uptodate = false;
udev_list_cleanup(&udev_device->tags_list);
}
/**
* udev_device_get_tags_list_entry:
* @udev_device: udev device
*
* Retrieve the list of tags attached to the udev device. The next
* list entry can be retrieved with udev_list_entry_get_next(),
* which returns #NULL if no more entries exist. The tag string
* can be retrieved from the list entry by udev_list_entry_get_name().
*
* Returns: the first entry of the tag list
**/
_public_ struct udev_list_entry *udev_device_get_tags_list_entry(struct udev_device *udev_device)
{
if (udev_device == NULL)
return NULL;
if (!udev_device->info_loaded)
udev_device_read_db(udev_device, NULL);
return udev_list_get_entry(&udev_device->tags_list);
}
/**
* udev_device_has_tag:
* @udev_device: udev device
* @tag: tag name
*
* Check if a given device has a certain tag associated.
*
* Returns: 1 if the tag is found. 0 otherwise.
**/
_public_ int udev_device_has_tag(struct udev_device *udev_device, const char *tag)
{
struct udev_list_entry *list_entry;
if (udev_device == NULL)
return false;
if (!udev_device->info_loaded)
udev_device_read_db(udev_device, NULL);
list_entry = udev_device_get_tags_list_entry(udev_device);
if (udev_list_entry_get_by_name(list_entry, tag) != NULL)
return true;
return false;
}
#define ENVP_SIZE 128
#define MONITOR_BUF_SIZE 4096
static int update_envp_monitor_buf(struct udev_device *udev_device)
{
struct udev_list_entry *list_entry;
char *s;
size_t l;
unsigned int i;
/* monitor buffer of property strings */
free(udev_device->monitor_buf);
udev_device->monitor_buf_len = 0;
udev_device->monitor_buf = malloc(MONITOR_BUF_SIZE);
if (udev_device->monitor_buf == NULL)
return -ENOMEM;
/* envp array, strings will point into monitor buffer */
if (udev_device->envp == NULL)
udev_device->envp = malloc(sizeof(char *) * ENVP_SIZE);
if (udev_device->envp == NULL)
return -ENOMEM;
i = 0;
s = udev_device->monitor_buf;
l = MONITOR_BUF_SIZE;
udev_list_entry_foreach(list_entry, udev_device_get_properties_list_entry(udev_device)) {
const char *key;
key = udev_list_entry_get_name(list_entry);
/* skip private variables */
if (key[0] == '.')
continue;
/* add string to envp array */
udev_device->envp[i++] = s;
if (i+1 >= ENVP_SIZE)
return -EINVAL;
/* add property string to monitor buffer */
l = strpcpyl(&s, l, key, "=", udev_list_entry_get_value(list_entry), NULL);
if (l == 0)
return -EINVAL;
/* advance past the trailing '\0' that strpcpyl() guarantees */
s++;
l--;
}
udev_device->envp[i] = NULL;
udev_device->monitor_buf_len = s - udev_device->monitor_buf;
udev_device->envp_uptodate = true;
return 0;
}
char **udev_device_get_properties_envp(struct udev_device *udev_device)
{
if (!udev_device->envp_uptodate)
if (update_envp_monitor_buf(udev_device) != 0)
return NULL;
return udev_device->envp;
}
ssize_t udev_device_get_properties_monitor_buf(struct udev_device *udev_device, const char **buf)
{
if (!udev_device->envp_uptodate)
if (update_envp_monitor_buf(udev_device) != 0)
return -EINVAL;
*buf = udev_device->monitor_buf;
return udev_device->monitor_buf_len;
}
int udev_device_set_action(struct udev_device *udev_device, const char *action)
{
free(udev_device->action);
udev_device->action = strdup(action);
if (udev_device->action == NULL)
return -ENOMEM;
udev_device_add_property(udev_device, "ACTION", udev_device->action);
return 0;
}
int udev_device_get_devlink_priority(struct udev_device *udev_device)
{
if (!udev_device->info_loaded)
udev_device_read_db(udev_device, NULL);
return udev_device->devlink_priority;
}
int udev_device_set_devlink_priority(struct udev_device *udev_device, int prio)
{
udev_device->devlink_priority = prio;
return 0;
}
int udev_device_get_watch_handle(struct udev_device *udev_device)
{
if (!udev_device->info_loaded)
udev_device_read_db(udev_device, NULL);
return udev_device->watch_handle;
}
int udev_device_set_watch_handle(struct udev_device *udev_device, int handle)
{
udev_device->watch_handle = handle;
return 0;
}
bool udev_device_get_db_persist(struct udev_device *udev_device)
{
return udev_device->db_persist;
}
void udev_device_set_db_persist(struct udev_device *udev_device)
{
udev_device->db_persist = true;
}
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