sd-device.c revision 6ad623a3f77e087e308f334525fd4046811f2a9a
/***
This file is part of systemd.
Copyright 2008-2012 Kay Sievers <kay@vrfy.org>
Copyright 2014 Tom Gundersen <teg@jklm.no>
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 <ctype.h>
#include <net/if.h>
#include <sys/types.h>
#include "sd-device.h"
#include "alloc-util.h"
#include "device-internal.h"
#include "device-private.h"
#include "device-util.h"
#include "fd-util.h"
#include "fileio.h"
#include "fs-util.h"
#include "hashmap.h"
#include "macro.h"
#include "parse-util.h"
#include "path-util.h"
#include "set.h"
#include "stat-util.h"
#include "string-util.h"
#include "strv.h"
#include "strxcpyx.h"
#include "util.h"
int device_new_aux(sd_device **ret) {
_cleanup_device_unref_ sd_device *device = NULL;
assert(ret);
device = new0(sd_device, 1);
if (!device)
return -ENOMEM;
device->n_ref = 1;
device->watch_handle = -1;
*ret = device;
device = NULL;
return 0;
}
_public_ sd_device *sd_device_ref(sd_device *device) {
if (device)
assert_se(++ device->n_ref >= 2);
return device;
}
_public_ sd_device *sd_device_unref(sd_device *device) {
if (device && -- device->n_ref == 0) {
sd_device_unref(device->parent);
free(device->syspath);
free(device->sysname);
free(device->devtype);
free(device->devname);
free(device->subsystem);
free(device->driver);
free(device->id_filename);
free(device->properties_strv);
free(device->properties_nulstr);
ordered_hashmap_free_free_free(device->properties);
ordered_hashmap_free_free_free(device->properties_db);
hashmap_free_free_free(device->sysattr_values);
set_free_free(device->sysattrs);
set_free_free(device->tags);
set_free_free(device->devlinks);
free(device);
}
return NULL;
}
int device_add_property_aux(sd_device *device, const char *_key, const char *_value, bool db) {
OrderedHashmap **properties;
assert(device);
assert(_key);
if (db)
properties = &device->properties_db;
else
properties = &device->properties;
if (_value) {
_cleanup_free_ char *key = NULL, *value = NULL, *old_key = NULL, *old_value = NULL;
int r;
r = ordered_hashmap_ensure_allocated(properties, &string_hash_ops);
if (r < 0)
return r;
key = strdup(_key);
if (!key)
return -ENOMEM;
value = strdup(_value);
if (!value)
return -ENOMEM;
old_value = ordered_hashmap_get2(*properties, key, (void**) &old_key);
r = ordered_hashmap_replace(*properties, key, value);
if (r < 0)
return r;
key = NULL;
value = NULL;
} else {
_cleanup_free_ char *key = NULL;
_cleanup_free_ char *value = NULL;
value = ordered_hashmap_remove2(*properties, _key, (void**) &key);
}
if (!db) {
device->properties_generation ++;
device->properties_buf_outdated = true;
}
return 0;
}
int device_add_property_internal(sd_device *device, const char *key, const char *value) {
return device_add_property_aux(device, key, value, false);
}
int device_set_syspath(sd_device *device, const char *_syspath, bool verify) {
_cleanup_free_ char *syspath = NULL;
const char *devpath;
int r;
assert(device);
assert(_syspath);
/* must be a subdirectory of /sys */
if (!path_startswith(_syspath, "/sys/")) {
log_debug("sd-device: syspath '%s' is not a subdirectory of /sys", _syspath);
return -EINVAL;
}
if (verify) {
r = readlink_and_canonicalize(_syspath, &syspath);
if (r == -ENOENT)
/* the device does not exist (any more?) */
return -ENODEV;
else if (r == -EINVAL) {
/* not a symlink */
syspath = canonicalize_file_name(_syspath);
if (!syspath) {
if (errno == ENOENT)
/* the device does not exist (any more?) */
return -ENODEV;
return log_debug_errno(errno, "sd-device: could not canonicalize '%s': %m", _syspath);
}
} else if (r < 0) {
log_debug_errno(r, "sd-device: could not get target of '%s': %m", _syspath);
return r;
}
if (path_startswith(syspath, "/sys/devices/")) {
char *path;
/* all 'devices' require an 'uevent' file */
path = strjoina(syspath, "/uevent");
r = access(path, F_OK);
if (r < 0) {
if (errno == ENOENT)
/* this is not a valid device */
return -ENODEV;
log_debug("sd-device: %s does not have an uevent file: %m", syspath);
return -errno;
}
} else {
/* everything else just just needs to be a directory */
if (!is_dir(syspath, false))
return -ENODEV;
}
} else {
syspath = strdup(_syspath);
if (!syspath)
return -ENOMEM;
}
devpath = syspath + strlen("/sys");
r = device_add_property_internal(device, "DEVPATH", devpath);
if (r < 0)
return r;
free(device->syspath);
device->syspath = syspath;
syspath = NULL;
device->devpath = devpath;
return 0;
}
_public_ int sd_device_new_from_syspath(sd_device **ret, const char *syspath) {
_cleanup_device_unref_ sd_device *device = NULL;
int r;
assert_return(ret, -EINVAL);
assert_return(syspath, -EINVAL);
r = device_new_aux(&device);
if (r < 0)
return r;
r = device_set_syspath(device, syspath, true);
if (r < 0)
return r;
*ret = device;
device = NULL;
return 0;
}
_public_ int sd_device_new_from_devnum(sd_device **ret, char type, dev_t devnum) {
char *syspath;
char id[DECIMAL_STR_MAX(unsigned) * 2 + 1];
assert_return(ret, -EINVAL);
assert_return(type == 'b' || type == 'c', -EINVAL);
/* use /sys/dev/{block,char}/<maj>:<min> link */
snprintf(id, sizeof(id), "%u:%u", major(devnum), minor(devnum));
syspath = strjoina("/sys/dev/", (type == 'b' ? "block" : "char"), "/", id);
return sd_device_new_from_syspath(ret, syspath);
}
_public_ int sd_device_new_from_subsystem_sysname(sd_device **ret, const char *subsystem, const char *sysname) {
char *syspath;
assert_return(ret, -EINVAL);
assert_return(subsystem, -EINVAL);
assert_return(sysname, -EINVAL);
if (streq(subsystem, "subsystem")) {
syspath = strjoina("/sys/subsystem/", sysname);
if (access(syspath, F_OK) >= 0)
return sd_device_new_from_syspath(ret, syspath);
syspath = strjoina("/sys/bus/", sysname);
if (access(syspath, F_OK) >= 0)
return sd_device_new_from_syspath(ret, syspath);
syspath = strjoina("/sys/class/", sysname);
if (access(syspath, F_OK) >= 0)
return sd_device_new_from_syspath(ret, syspath);
} else if (streq(subsystem, "module")) {
syspath = strjoina("/sys/module/", sysname);
if (access(syspath, F_OK) >= 0)
return sd_device_new_from_syspath(ret, syspath);
} else if (streq(subsystem, "drivers")) {
char subsys[PATH_MAX];
char *driver;
strscpy(subsys, sizeof(subsys), sysname);
driver = strchr(subsys, ':');
if (driver) {
driver[0] = '\0';
driver++;
syspath = strjoina("/sys/subsystem/", subsys, "/drivers/", driver);
if (access(syspath, F_OK) >= 0)
return sd_device_new_from_syspath(ret, syspath);
syspath = strjoina("/sys/bus/", subsys, "/drivers/", driver);
if (access(syspath, F_OK) >= 0)
return sd_device_new_from_syspath(ret, syspath);
} else
return -EINVAL;
} else {
char *name;
size_t len = 0;
/* translate sysname back to sysfs filename */
name = strdupa(sysname);
while (name[len] != '\0') {
if (name[len] == '/')
name[len] = '!';
len ++;
}
syspath = strjoina("/sys/subsystem/", subsystem, "/devices/", name);
if (access(syspath, F_OK) >= 0)
return sd_device_new_from_syspath(ret, syspath);
syspath = strjoina("/sys/bus/", subsystem, "/devices/", name);
if (access(syspath, F_OK) >= 0)
return sd_device_new_from_syspath(ret, syspath);
syspath = strjoina("/sys/class/", subsystem, "/", name);
if (access(syspath, F_OK) >= 0)
return sd_device_new_from_syspath(ret, syspath);
}
return -ENODEV;
}
int device_set_devtype(sd_device *device, const char *_devtype) {
_cleanup_free_ char *devtype = NULL;
int r;
assert(device);
assert(_devtype);
devtype = strdup(_devtype);
if (!devtype)
return -ENOMEM;
r = device_add_property_internal(device, "DEVTYPE", devtype);
if (r < 0)
return r;
free(device->devtype);
device->devtype = devtype;
devtype = NULL;
return 0;
}
int device_set_ifindex(sd_device *device, const char *_ifindex) {
int ifindex, r;
assert(device);
assert(_ifindex);
r = parse_ifindex(_ifindex, &ifindex);
if (r < 0)
return r;
r = device_add_property_internal(device, "IFINDEX", _ifindex);
if (r < 0)
return r;
device->ifindex = ifindex;
return 0;
}
int device_set_devname(sd_device *device, const char *_devname) {
_cleanup_free_ char *devname = NULL;
int r;
assert(device);
assert(_devname);
if (_devname[0] != '/') {
r = asprintf(&devname, "/dev/%s", _devname);
if (r < 0)
return -ENOMEM;
} else {
devname = strdup(_devname);
if (!devname)
return -ENOMEM;
}
r = device_add_property_internal(device, "DEVNAME", devname);
if (r < 0)
return r;
free(device->devname);
device->devname = devname;
devname = NULL;
return 0;
}
int device_set_devmode(sd_device *device, const char *_devmode) {
unsigned devmode;
int r;
assert(device);
assert(_devmode);
r = safe_atou(_devmode, &devmode);
if (r < 0)
return r;
if (devmode > 07777)
return -EINVAL;
r = device_add_property_internal(device, "DEVMODE", _devmode);
if (r < 0)
return r;
device->devmode = devmode;
return 0;
}
int device_set_devnum(sd_device *device, const char *major, const char *minor) {
unsigned maj = 0, min = 0;
int r;
assert(device);
assert(major);
r = safe_atou(major, &maj);
if (r < 0)
return r;
if (!maj)
return 0;
if (minor) {
r = safe_atou(minor, &min);
if (r < 0)
return r;
}
r = device_add_property_internal(device, "MAJOR", major);
if (r < 0)
return r;
if (minor) {
r = device_add_property_internal(device, "MINOR", minor);
if (r < 0)
return r;
}
device->devnum = makedev(maj, min);
return 0;
}
static int handle_uevent_line(sd_device *device, const char *key, const char *value, const char **major, const char **minor) {
int r;
assert(device);
assert(key);
assert(value);
assert(major);
assert(minor);
if (streq(key, "DEVTYPE")) {
r = device_set_devtype(device, value);
if (r < 0)
return r;
} else if (streq(key, "IFINDEX")) {
r = device_set_ifindex(device, value);
if (r < 0)
return r;
} else if (streq(key, "DEVNAME")) {
r = device_set_devname(device, value);
if (r < 0)
return r;
} else if (streq(key, "DEVMODE")) {
r = device_set_devmode(device, value);
if (r < 0)
return r;
} else if (streq(key, "MAJOR"))
*major = value;
else if (streq(key, "MINOR"))
*minor = value;
else {
r = device_add_property_internal(device, key, value);
if (r < 0)
return r;
}
return 0;
}
int device_read_uevent_file(sd_device *device) {
_cleanup_free_ char *uevent = NULL;
const char *syspath, *key, *value, *major = NULL, *minor = NULL;
char *path;
size_t uevent_len;
unsigned i;
int r;
enum {
PRE_KEY,
KEY,
PRE_VALUE,
VALUE,
INVALID_LINE,
} state = PRE_KEY;
assert(device);
if (device->uevent_loaded || device->sealed)
return 0;
device->uevent_loaded = true;
r = sd_device_get_syspath(device, &syspath);
if (r < 0)
return r;
path = strjoina(syspath, "/uevent");
r = read_full_file(path, &uevent, &uevent_len);
if (r == -EACCES)
/* empty uevent files may be write-only */
return 0;
else if (r == -ENOENT)
/* some devices may not have uevent files, see set_syspath() */
return 0;
else if (r < 0) {
log_debug_errno(r, "sd-device: failed to read uevent file '%s': %m", path);
return r;
}
for (i = 0; i < uevent_len; i++) {
switch (state) {
case PRE_KEY:
if (!strchr(NEWLINE, uevent[i])) {
key = &uevent[i];
state = KEY;
}
break;
case KEY:
if (uevent[i] == '=') {
uevent[i] = '\0';
state = PRE_VALUE;
} else if (strchr(NEWLINE, uevent[i])) {
uevent[i] = '\0';
log_debug("sd-device: ignoring invalid uevent line '%s'", key);
state = PRE_KEY;
}
break;
case PRE_VALUE:
value = &uevent[i];
state = VALUE;
break;
case VALUE:
if (strchr(NEWLINE, uevent[i])) {
uevent[i] = '\0';
r = handle_uevent_line(device, key, value, &major, &minor);
if (r < 0)
log_debug_errno(r, "sd-device: failed to handle uevent entry '%s=%s': %m", key, value);
state = PRE_KEY;
}
break;
default:
assert_not_reached("invalid state when parsing uevent file");
}
}
if (major) {
r = device_set_devnum(device, major, minor);
if (r < 0)
log_debug_errno(r, "sd-device: could not set 'MAJOR=%s' or 'MINOR=%s' from '%s': %m", major, minor, path);
}
return 0;
}
_public_ int sd_device_get_ifindex(sd_device *device, int *ifindex) {
int r;
assert_return(device, -EINVAL);
assert_return(ifindex, -EINVAL);
r = device_read_uevent_file(device);
if (r < 0)
return r;
*ifindex = device->ifindex;
return 0;
}
_public_ int sd_device_new_from_device_id(sd_device **ret, const char *id) {
int r;
assert_return(ret, -EINVAL);
assert_return(id, -EINVAL);
switch (id[0]) {
case 'b':
case 'c':
{
char type;
int maj, min;
r = sscanf(id, "%c%i:%i", &type, &maj, &min);
if (r != 3)
return -EINVAL;
return sd_device_new_from_devnum(ret, type, makedev(maj, min));
}
case 'n':
{
_cleanup_device_unref_ sd_device *device = NULL;
_cleanup_close_ int sk = -1;
struct ifreq ifr = {};
int ifindex;
r = parse_ifindex(&id[1], &ifr.ifr_ifindex);
if (r < 0)
return r;
sk = socket(PF_INET, SOCK_DGRAM, 0);
if (sk < 0)
return -errno;
r = ioctl(sk, SIOCGIFNAME, &ifr);
if (r < 0)
return -errno;
r = sd_device_new_from_subsystem_sysname(&device, "net", ifr.ifr_name);
if (r < 0)
return r;
r = sd_device_get_ifindex(device, &ifindex);
if (r < 0)
return r;
/* this is racey, so we might end up with the wrong device */
if (ifr.ifr_ifindex != ifindex)
return -ENODEV;
*ret = device;
device = NULL;
return 0;
}
case '+':
{
char subsys[PATH_MAX];
char *sysname;
(void)strscpy(subsys, sizeof(subsys), id + 1);
sysname = strchr(subsys, ':');
if (!sysname)
return -EINVAL;
sysname[0] = '\0';
sysname ++;
return sd_device_new_from_subsystem_sysname(ret, subsys, sysname);
}
default:
return -EINVAL;
}
}
_public_ int sd_device_get_syspath(sd_device *device, const char **ret) {
assert_return(device, -EINVAL);
assert_return(ret, -EINVAL);
assert(path_startswith(device->syspath, "/sys/"));
*ret = device->syspath;
return 0;
}
static int device_new_from_child(sd_device **ret, sd_device *child) {
_cleanup_free_ char *path = NULL;
const char *subdir, *syspath;
int r;
assert(ret);
assert(child);
r = sd_device_get_syspath(child, &syspath);
if (r < 0)
return r;
path = strdup(syspath);
if (!path)
return -ENOMEM;
subdir = path + strlen("/sys");
for (;;) {
char *pos;
pos = strrchr(subdir, '/');
if (!pos || pos < subdir + 2)
break;
*pos = '\0';
r = sd_device_new_from_syspath(ret, path);
if (r < 0)
continue;
return 0;
}
return -ENODEV;
}
_public_ int sd_device_get_parent(sd_device *child, sd_device **ret) {
assert_return(ret, -EINVAL);
assert_return(child, -EINVAL);
if (!child->parent_set) {
child->parent_set = true;
(void)device_new_from_child(&child->parent, child);
}
if (!child->parent)
return -ENOENT;
*ret = child->parent;
return 0;
}
int device_set_subsystem(sd_device *device, const char *_subsystem) {
_cleanup_free_ char *subsystem = NULL;
int r;
assert(device);
assert(_subsystem);
subsystem = strdup(_subsystem);
if (!subsystem)
return -ENOMEM;
r = device_add_property_internal(device, "SUBSYSTEM", subsystem);
if (r < 0)
return r;
free(device->subsystem);
device->subsystem = subsystem;
subsystem = NULL;
device->subsystem_set = true;
return 0;
}
_public_ int sd_device_get_subsystem(sd_device *device, const char **ret) {
assert_return(ret, -EINVAL);
assert_return(device, -EINVAL);
if (!device->subsystem_set) {
_cleanup_free_ char *subsystem = NULL;
const char *syspath;
char *path;
int r;
/* read 'subsystem' link */
r = sd_device_get_syspath(device, &syspath);
if (r < 0)
return r;
path = strjoina(syspath, "/subsystem");
r = readlink_value(path, &subsystem);
if (r >= 0)
r = device_set_subsystem(device, subsystem);
/* use implicit names */
else if (path_startswith(device->devpath, "/module/"))
r = device_set_subsystem(device, "module");
else if (strstr(device->devpath, "/drivers/"))
r = device_set_subsystem(device, "drivers");
else if (path_startswith(device->devpath, "/subsystem/") ||
path_startswith(device->devpath, "/class/") ||
path_startswith(device->devpath, "/bus/"))
r = device_set_subsystem(device, "subsystem");
if (r < 0 && r != -ENOENT)
return log_debug_errno(r, "sd-device: could not set subsystem for %s: %m", device->devpath);
device->subsystem_set = true;
}
if (!device->subsystem)
return -ENOENT;
*ret = device->subsystem;
return 0;
}
_public_ int sd_device_get_devtype(sd_device *device, const char **devtype) {
int r;
assert(devtype);
assert(device);
r = device_read_uevent_file(device);
if (r < 0)
return r;
*devtype = device->devtype;
return 0;
}
_public_ int sd_device_get_parent_with_subsystem_devtype(sd_device *child, const char *subsystem, const char *devtype, sd_device **ret) {
sd_device *parent = NULL;
int r;
assert_return(child, -EINVAL);
assert_return(subsystem, -EINVAL);
r = sd_device_get_parent(child, &parent);
while (r >= 0) {
const char *parent_subsystem = NULL;
const char *parent_devtype = NULL;
(void)sd_device_get_subsystem(parent, &parent_subsystem);
if (streq_ptr(parent_subsystem, subsystem)) {
if (!devtype)
break;
(void)sd_device_get_devtype(parent, &parent_devtype);
if (streq_ptr(parent_devtype, devtype))
break;
}
r = sd_device_get_parent(parent, &parent);
}
if (r < 0)
return r;
*ret = parent;
return 0;
}
_public_ int sd_device_get_devnum(sd_device *device, dev_t *devnum) {
int r;
assert_return(device, -EINVAL);
assert_return(devnum, -EINVAL);
r = device_read_uevent_file(device);
if (r < 0)
return r;
*devnum = device->devnum;
return 0;
}
int device_set_driver(sd_device *device, const char *_driver) {
_cleanup_free_ char *driver = NULL;
int r;
assert(device);
assert(_driver);
driver = strdup(_driver);
if (!driver)
return -ENOMEM;
r = device_add_property_internal(device, "DRIVER", driver);
if (r < 0)
return r;
free(device->driver);
device->driver = driver;
driver = NULL;
device->driver_set = true;
return 0;
}
_public_ int sd_device_get_driver(sd_device *device, const char **ret) {
assert_return(device, -EINVAL);
assert_return(ret, -EINVAL);
if (!device->driver_set) {
_cleanup_free_ char *driver = NULL;
const char *syspath;
char *path;
int r;
r = sd_device_get_syspath(device, &syspath);
if (r < 0)
return r;
path = strjoina(syspath, "/driver");
r = readlink_value(path, &driver);
if (r >= 0) {
r = device_set_driver(device, driver);
if (r < 0)
return log_debug_errno(r, "sd-device: could not set driver for %s: %m", device->devpath);
} else if (r == -ENOENT)
device->driver_set = true;
else
return log_debug_errno(r, "sd-device: could not set driver for %s: %m", device->devpath);
}
if (!device->driver)
return -ENOENT;
*ret = device->driver;
return 0;
}
_public_ int sd_device_get_devpath(sd_device *device, const char **devpath) {
assert_return(device, -EINVAL);
assert_return(devpath, -EINVAL);
assert(device->devpath);
assert(device->devpath[0] == '/');
*devpath = device->devpath;
return 0;
}
_public_ int sd_device_get_devname(sd_device *device, const char **devname) {
int r;
assert_return(device, -EINVAL);
assert_return(devname, -EINVAL);
r = device_read_uevent_file(device);
if (r < 0)
return r;
if (!device->devname)
return -ENOENT;
assert(path_startswith(device->devname, "/dev/"));
*devname = device->devname;
return 0;
}
static int device_set_sysname(sd_device *device) {
_cleanup_free_ char *sysname = NULL;
const char *sysnum = NULL;
const char *pos;
size_t len = 0;
pos = strrchr(device->devpath, '/');
if (!pos)
return -EINVAL;
pos ++;
/* devpath is not a root directory */
if (*pos == '\0' || pos <= device->devpath)
return -EINVAL;
sysname = strdup(pos);
if (!sysname)
return -ENOMEM;
/* some devices have '!' in their name, change that to '/' */
while (sysname[len] != '\0') {
if (sysname[len] == '!')
sysname[len] = '/';
len ++;
}
/* trailing number */
while (len > 0 && isdigit(sysname[--len]))
sysnum = &sysname[len];
if (len == 0)
sysnum = NULL;
free(device->sysname);
device->sysname = sysname;
sysname = NULL;
device->sysnum = sysnum;
device->sysname_set = true;
return 0;
}
_public_ int sd_device_get_sysname(sd_device *device, const char **ret) {
int r;
assert_return(device, -EINVAL);
assert_return(ret, -EINVAL);
if (!device->sysname_set) {
r = device_set_sysname(device);
if (r < 0)
return r;
}
assert_return(device->sysname, -ENOENT);
*ret = device->sysname;
return 0;
}
_public_ int sd_device_get_sysnum(sd_device *device, const char **ret) {
int r;
assert_return(device, -EINVAL);
assert_return(ret, -EINVAL);
if (!device->sysname_set) {
r = device_set_sysname(device);
if (r < 0)
return r;
}
*ret = device->sysnum;
return 0;
}
static bool is_valid_tag(const char *tag) {
assert(tag);
return !strchr(tag, ':') && !strchr(tag, ' ');
}
int device_add_tag(sd_device *device, const char *tag) {
int r;
assert(device);
assert(tag);
if (!is_valid_tag(tag))
return -EINVAL;
r = set_ensure_allocated(&device->tags, &string_hash_ops);
if (r < 0)
return r;
r = set_put_strdup(device->tags, tag);
if (r < 0)
return r;
device->tags_generation ++;
device->property_tags_outdated = true;
return 0;
}
int device_add_devlink(sd_device *device, const char *devlink) {
int r;
assert(device);
assert(devlink);
r = set_ensure_allocated(&device->devlinks, &string_hash_ops);
if (r < 0)
return r;
r = set_put_strdup(device->devlinks, devlink);
if (r < 0)
return r;
device->devlinks_generation ++;
device->property_devlinks_outdated = true;
return 0;
}
static int device_add_property_internal_from_string(sd_device *device, const char *str) {
_cleanup_free_ char *key = NULL;
char *value;
assert(device);
assert(str);
key = strdup(str);
if (!key)
return -ENOMEM;
value = strchr(key, '=');
if (!value)
return -EINVAL;
*value = '\0';
if (isempty(++value))
value = NULL;
return device_add_property_internal(device, key, value);
}
int device_set_usec_initialized(sd_device *device, const char *initialized) {
uint64_t usec_initialized;
int r;
assert(device);
assert(initialized);
r = safe_atou64(initialized, &usec_initialized);
if (r < 0)
return r;
r = device_add_property_internal(device, "USEC_INITIALIZED", initialized);
if (r < 0)
return r;
device->usec_initialized = usec_initialized;
return 0;
}
static int handle_db_line(sd_device *device, char key, const char *value) {
char *path;
int r;
assert(device);
assert(value);
switch (key) {
case 'G':
r = device_add_tag(device, value);
if (r < 0)
return r;
break;
case 'S':
path = strjoina("/dev/", value);
r = device_add_devlink(device, path);
if (r < 0)
return r;
break;
case 'E':
r = device_add_property_internal_from_string(device, value);
if (r < 0)
return r;
break;
case 'I':
r = device_set_usec_initialized(device, value);
if (r < 0)
return r;
break;
case 'L':
r = safe_atoi(value, &device->devlink_priority);
if (r < 0)
return r;
break;
case 'W':
r = safe_atoi(value, &device->watch_handle);
if (r < 0)
return r;
break;
default:
log_debug("device db: unknown key '%c'", key);
}
return 0;
}
int device_get_id_filename(sd_device *device, const char **ret) {
assert(device);
assert(ret);
if (!device->id_filename) {
_cleanup_free_ char *id = NULL;
const char *subsystem;
dev_t devnum;
int ifindex, r;
r = sd_device_get_subsystem(device, &subsystem);
if (r < 0)
return r;
r = sd_device_get_devnum(device, &devnum);
if (r < 0)
return r;
r = sd_device_get_ifindex(device, &ifindex);
if (r < 0)
return r;
if (major(devnum) > 0) {
assert(subsystem);
/* use dev_t -- b259:131072, c254:0 */
r = asprintf(&id, "%c%u:%u",
streq(subsystem, "block") ? 'b' : 'c',
major(devnum), minor(devnum));
if (r < 0)
return -ENOMEM;
} else if (ifindex > 0) {
/* use netdev ifindex -- n3 */
r = asprintf(&id, "n%u", ifindex);
if (r < 0)
return -ENOMEM;
} else {
/* use $subsys:$sysname -- pci:0000:00:1f.2
* sysname() has '!' translated, get it from devpath
*/
const char *sysname;
sysname = basename(device->devpath);
if (!sysname)
return -EINVAL;
if (!subsystem)
return -EINVAL;
r = asprintf(&id, "+%s:%s", subsystem, sysname);
if (r < 0)
return -ENOMEM;
}
device->id_filename = id;
id = NULL;
}
*ret = device->id_filename;
return 0;
}
int device_read_db_aux(sd_device *device, bool force) {
_cleanup_free_ char *db = NULL;
char *path;
const char *id, *value;
char key;
size_t db_len;
unsigned i;
int r;
enum {
PRE_KEY,
KEY,
PRE_VALUE,
VALUE,
INVALID_LINE,
} state = PRE_KEY;
if (device->db_loaded || (!force && device->sealed))
return 0;
device->db_loaded = true;
r = device_get_id_filename(device, &id);
if (r < 0)
return r;
path = strjoina("/run/udev/data/", id);
r = read_full_file(path, &db, &db_len);
if (r < 0) {
if (r == -ENOENT)
return 0;
else
return log_debug_errno(r, "sd-device: failed to read db '%s': %m", path);
}
/* devices with a database entry are initialized */
device->is_initialized = true;
for (i = 0; i < db_len; i++) {
switch (state) {
case PRE_KEY:
if (!strchr(NEWLINE, db[i])) {
key = db[i];
state = KEY;
}
break;
case KEY:
if (db[i] != ':') {
log_debug("sd-device: ignoring invalid db entry with key '%c'", key);
state = INVALID_LINE;
} else {
db[i] = '\0';
state = PRE_VALUE;
}
break;
case PRE_VALUE:
value = &db[i];
state = VALUE;
break;
case INVALID_LINE:
if (strchr(NEWLINE, db[i]))
state = PRE_KEY;
break;
case VALUE:
if (strchr(NEWLINE, db[i])) {
db[i] = '\0';
r = handle_db_line(device, key, value);
if (r < 0)
log_debug_errno(r, "sd-device: failed to handle db entry '%c:%s': %m", key, value);
state = PRE_KEY;
}
break;
default:
assert_not_reached("invalid state when parsing db");
}
}
return 0;
}
static int device_read_db(sd_device *device) {
return device_read_db_aux(device, false);
}
_public_ int sd_device_get_is_initialized(sd_device *device, int *initialized) {
int r;
assert_return(device, -EINVAL);
assert_return(initialized, -EINVAL);
r = device_read_db(device);
if (r < 0)
return r;
*initialized = device->is_initialized;
return 0;
}
_public_ int sd_device_get_usec_since_initialized(sd_device *device, uint64_t *usec) {
usec_t now_ts;
int r;
assert_return(device, -EINVAL);
assert_return(usec, -EINVAL);
r = device_read_db(device);
if (r < 0)
return r;
if (!device->is_initialized)
return -EBUSY;
if (!device->usec_initialized)
return -ENODATA;
now_ts = now(clock_boottime_or_monotonic());
if (now_ts < device->usec_initialized)
return -EIO;
*usec = now_ts - device->usec_initialized;
return 0;
}
_public_ const char *sd_device_get_tag_first(sd_device *device) {
void *v;
assert_return(device, NULL);
(void) device_read_db(device);
device->tags_iterator_generation = device->tags_generation;
device->tags_iterator = ITERATOR_FIRST;
set_iterate(device->tags, &device->tags_iterator, &v);
return v;
}
_public_ const char *sd_device_get_tag_next(sd_device *device) {
void *v;
assert_return(device, NULL);
(void) device_read_db(device);
if (device->tags_iterator_generation != device->tags_generation)
return NULL;
set_iterate(device->tags, &device->tags_iterator, &v);
return v;
}
_public_ const char *sd_device_get_devlink_first(sd_device *device) {
void *v;
assert_return(device, NULL);
(void) device_read_db(device);
device->devlinks_iterator_generation = device->devlinks_generation;
device->devlinks_iterator = ITERATOR_FIRST;
set_iterate(device->devlinks, &device->devlinks_iterator, &v);
return v;
}
_public_ const char *sd_device_get_devlink_next(sd_device *device) {
void *v;
assert_return(device, NULL);
(void) device_read_db(device);
if (device->devlinks_iterator_generation != device->devlinks_generation)
return NULL;
set_iterate(device->devlinks, &device->devlinks_iterator, &v);
return v;
}
static int device_properties_prepare(sd_device *device) {
int r;
assert(device);
r = device_read_uevent_file(device);
if (r < 0)
return r;
r = device_read_db(device);
if (r < 0)
return r;
if (device->property_devlinks_outdated) {
char *devlinks = NULL;
const char *devlink;
devlink = sd_device_get_devlink_first(device);
if (devlink)
devlinks = strdupa(devlink);
while ((devlink = sd_device_get_devlink_next(device)))
devlinks = strjoina(devlinks, " ", devlink);
r = device_add_property_internal(device, "DEVLINKS", devlinks);
if (r < 0)
return r;
device->property_devlinks_outdated = false;
}
if (device->property_tags_outdated) {
char *tags = NULL;
const char *tag;
tag = sd_device_get_tag_first(device);
if (tag)
tags = strjoina(":", tag);
while ((tag = sd_device_get_tag_next(device)))
tags = strjoina(tags, ":", tag);
tags = strjoina(tags, ":");
r = device_add_property_internal(device, "TAGS", tags);
if (r < 0)
return r;
device->property_tags_outdated = false;
}
return 0;
}
_public_ const char *sd_device_get_property_first(sd_device *device, const char **_value) {
const char *key;
const char *value;
int r;
assert_return(device, NULL);
r = device_properties_prepare(device);
if (r < 0)
return NULL;
device->properties_iterator_generation = device->properties_generation;
device->properties_iterator = ITERATOR_FIRST;
ordered_hashmap_iterate(device->properties, &device->properties_iterator, (void**)&value, (const void**)&key);
if (_value)
*_value = value;
return key;
}
_public_ const char *sd_device_get_property_next(sd_device *device, const char **_value) {
const char *key;
const char *value;
int r;
assert_return(device, NULL);
r = device_properties_prepare(device);
if (r < 0)
return NULL;
if (device->properties_iterator_generation != device->properties_generation)
return NULL;
ordered_hashmap_iterate(device->properties, &device->properties_iterator, (void**)&value, (const void**)&key);
if (_value)
*_value = value;
return key;
}
static int device_sysattrs_read_all(sd_device *device) {
_cleanup_closedir_ DIR *dir = NULL;
const char *syspath;
struct dirent *dent;
int r;
assert(device);
if (device->sysattrs_read)
return 0;
r = sd_device_get_syspath(device, &syspath);
if (r < 0)
return r;
dir = opendir(syspath);
if (!dir)
return -errno;
r = set_ensure_allocated(&device->sysattrs, &string_hash_ops);
if (r < 0)
return r;
for (dent = readdir(dir); dent != NULL; dent = readdir(dir)) {
char *path;
struct stat statbuf;
/* only handle symlinks and regular files */
if (dent->d_type != DT_LNK && dent->d_type != DT_REG)
continue;
path = strjoina(syspath, "/", dent->d_name);
if (lstat(path, &statbuf) != 0)
continue;
if (!(statbuf.st_mode & S_IRUSR))
continue;
r = set_put_strdup(device->sysattrs, dent->d_name);
if (r < 0)
return r;
}
device->sysattrs_read = true;
return 0;
}
_public_ const char *sd_device_get_sysattr_first(sd_device *device) {
void *v;
int r;
assert_return(device, NULL);
if (!device->sysattrs_read) {
r = device_sysattrs_read_all(device);
if (r < 0) {
errno = -r;
return NULL;
}
}
device->sysattrs_iterator = ITERATOR_FIRST;
set_iterate(device->sysattrs, &device->sysattrs_iterator, &v);
return v;
}
_public_ const char *sd_device_get_sysattr_next(sd_device *device) {
void *v;
assert_return(device, NULL);
if (!device->sysattrs_read)
return NULL;
set_iterate(device->sysattrs, &device->sysattrs_iterator, &v);
return v;
}
_public_ int sd_device_has_tag(sd_device *device, const char *tag) {
assert_return(device, -EINVAL);
assert_return(tag, -EINVAL);
(void) device_read_db(device);
return !!set_contains(device->tags, tag);
}
_public_ int sd_device_get_property_value(sd_device *device, const char *key, const char **_value) {
char *value;
int r;
assert_return(device, -EINVAL);
assert_return(key, -EINVAL);
assert_return(_value, -EINVAL);
r = device_properties_prepare(device);
if (r < 0)
return r;
value = ordered_hashmap_get(device->properties, key);
if (!value)
return -ENOENT;
*_value = value;
return 0;
}
/* replaces the value if it already exists */
static int device_add_sysattr_value(sd_device *device, const char *_key, char *value) {
_cleanup_free_ char *key = NULL;
_cleanup_free_ char *value_old = NULL;
int r;
assert(device);
assert(_key);
r = hashmap_ensure_allocated(&device->sysattr_values, &string_hash_ops);
if (r < 0)
return r;
value_old = hashmap_remove2(device->sysattr_values, _key, (void **)&key);
if (!key) {
key = strdup(_key);
if (!key)
return -ENOMEM;
}
r = hashmap_put(device->sysattr_values, key, value);
if (r < 0)
return r;
key = NULL;
return 0;
}
static int device_get_sysattr_value(sd_device *device, const char *_key, const char **_value) {
const char *key = NULL, *value;
assert(device);
assert(_key);
value = hashmap_get2(device->sysattr_values, _key, (void **) &key);
if (!key)
return -ENOENT;
if (_value)
*_value = value;
return 0;
}
/* We cache all sysattr lookups. If an attribute does not exist, it is stored
* with a NULL value in the cache, otherwise the returned string is stored */
_public_ int sd_device_get_sysattr_value(sd_device *device, const char *sysattr, const char **_value) {
_cleanup_free_ char *value = NULL;
const char *syspath, *cached_value = NULL;
char *path;
struct stat statbuf;
int r;
assert_return(device, -EINVAL);
assert_return(sysattr, -EINVAL);
/* look for possibly already cached result */
r = device_get_sysattr_value(device, sysattr, &cached_value);
if (r != -ENOENT) {
if (r < 0)
return r;
if (!cached_value)
/* we looked up the sysattr before and it did not exist */
return -ENOENT;
if (_value)
*_value = cached_value;
return 0;
}
r = sd_device_get_syspath(device, &syspath);
if (r < 0)
return r;
path = strjoina(syspath, "/", sysattr);
r = lstat(path, &statbuf);
if (r < 0) {
/* remember that we could not access the sysattr */
r = device_add_sysattr_value(device, sysattr, NULL);
if (r < 0)
return r;
return -ENOENT;
} else 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 (STR_IN_SET(sysattr, "driver", "subsystem", "module")) {
r = readlink_value(path, &value);
if (r < 0)
return r;
} else
return -EINVAL;
} else if (S_ISDIR(statbuf.st_mode)) {
/* skip directories */
return -EINVAL;
} else if (!(statbuf.st_mode & S_IRUSR)) {
/* skip non-readable files */
return -EPERM;
} else {
size_t size;
/* read attribute value */
r = read_full_file(path, &value, &size);
if (r < 0)
return r;
/* drop trailing newlines */
while (size > 0 && value[--size] == '\n')
value[size] = '\0';
}
r = device_add_sysattr_value(device, sysattr, value);
if (r < 0)
return r;
*_value = value;
value = NULL;
return 0;
}
static void device_remove_sysattr_value(sd_device *device, const char *_key) {
_cleanup_free_ char *key = NULL;
_cleanup_free_ char *value = NULL;
assert(device);
assert(_key);
value = hashmap_remove2(device->sysattr_values, _key, (void **) &key);
return;
}
/* set the attribute and save it in the cache. If a NULL value is passed the
* attribute is cleared from the cache */
_public_ int sd_device_set_sysattr_value(sd_device *device, const char *sysattr, char *_value) {
_cleanup_close_ int fd = -1;
_cleanup_free_ char *value = NULL;
const char *syspath;
char *path;
struct stat statbuf;
size_t value_len = 0;
ssize_t size;
int r;
assert_return(device, -EINVAL);
assert_return(sysattr, -EINVAL);
if (!_value) {
device_remove_sysattr_value(device, sysattr);
return 0;
}
r = sd_device_get_syspath(device, &syspath);
if (r < 0)
return r;
path = strjoina(syspath, "/", sysattr);
r = lstat(path, &statbuf);
if (r < 0) {
value = strdup("");
if (!value)
return -ENOMEM;
r = device_add_sysattr_value(device, sysattr, value);
if (r < 0)
return r;
return -ENXIO;
}
if (S_ISLNK(statbuf.st_mode))
return -EINVAL;
/* skip directories */
if (S_ISDIR(statbuf.st_mode))
return -EISDIR;
/* skip non-readable files */
if ((statbuf.st_mode & S_IRUSR) == 0)
return -EACCES;
value_len = strlen(_value);
/* drop trailing newlines */
while (value_len > 0 && _value[value_len - 1] == '\n')
_value[--value_len] = '\0';
/* value length is limited to 4k */
if (value_len > 4096)
return -EINVAL;
fd = open(path, O_WRONLY | O_CLOEXEC);
if (fd < 0)
return -errno;
value = strdup(_value);
if (!value)
return -ENOMEM;
size = write(fd, value, value_len);
if (size < 0)
return -errno;
if ((size_t)size != value_len)
return -EIO;
r = device_add_sysattr_value(device, sysattr, value);
if (r < 0)
return r;
value = NULL;
return 0;
}