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Diffstat (limited to 'src/libsystemd/libsystemd-internal/sd-device/sd-device.c')
-rw-r--r--src/libsystemd/libsystemd-internal/sd-device/sd-device.c1884
1 files changed, 1884 insertions, 0 deletions
diff --git a/src/libsystemd/libsystemd-internal/sd-device/sd-device.c b/src/libsystemd/libsystemd-internal/sd-device/sd-device.c
new file mode 100644
index 0000000000..d21a67cd4c
--- /dev/null
+++ b/src/libsystemd/libsystemd-internal/sd-device/sd-device.c
@@ -0,0 +1,1884 @@
+/***
+ 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 <systemd/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_(sd_device_unrefp) 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_(sd_device_unrefp) 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 = NULL, *value = NULL, *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_(sd_device_unrefp) 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;
+
+ (void) 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;
+
+ (void) 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;
+
+ (void) 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;
+
+ (void) 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) {
+ _cleanup_free_ char *devlinks = NULL;
+ size_t devlinks_allocated = 0, devlinks_len = 0;
+ const char *devlink;
+
+ for (devlink = sd_device_get_devlink_first(device); devlink; devlink = sd_device_get_devlink_next(device)) {
+ char *e;
+
+ if (!GREEDY_REALLOC(devlinks, devlinks_allocated, devlinks_len + strlen(devlink) + 2))
+ return -ENOMEM;
+ if (devlinks_len > 0)
+ stpcpy(devlinks + devlinks_len++, " ");
+ e = stpcpy(devlinks + devlinks_len, devlink);
+ devlinks_len = e - devlinks;
+ }
+
+ r = device_add_property_internal(device, "DEVLINKS", devlinks);
+ if (r < 0)
+ return r;
+
+ device->property_devlinks_outdated = false;
+ }
+
+ if (device->property_tags_outdated) {
+ _cleanup_free_ char *tags = NULL;
+ size_t tags_allocated = 0, tags_len = 0;
+ const char *tag;
+
+ if (!GREEDY_REALLOC(tags, tags_allocated, 2))
+ return -ENOMEM;
+ stpcpy(tags, ":");
+ tags_len++;
+
+ for (tag = sd_device_get_tag_first(device); tag; tag = sd_device_get_tag_next(device)) {
+ char *e;
+
+ if (!GREEDY_REALLOC(tags, tags_allocated, tags_len + strlen(tag) + 2))
+ return -ENOMEM;
+ e = stpcpy(stpcpy(tags + tags_len, tag), ":");
+ tags_len = e - 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;
+
+ (void) 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;
+
+ (void) 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;
+}
generated by cgit v1.2.3-54-g00ecf (git 2.45.2) at 2024-12-05 01:08:20 +0000