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-rw-r--r--src/libsystemd/sd-device/sd-device.c2648
1 files changed, 2648 insertions, 0 deletions
diff --git a/src/libsystemd/sd-device/sd-device.c b/src/libsystemd/sd-device/sd-device.c
new file mode 100644
index 0000000..f2193e2
--- /dev/null
+++ b/src/libsystemd/sd-device/sd-device.c
@@ -0,0 +1,2648 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+
+#include <ctype.h>
+#include <net/if.h>
+#include <sys/ioctl.h>
+#include <sys/types.h>
+
+#include "sd-device.h"
+
+#include "alloc-util.h"
+#include "chase-symlinks.h"
+#include "device-internal.h"
+#include "device-private.h"
+#include "device-util.h"
+#include "devnum-util.h"
+#include "dirent-util.h"
+#include "env-util.h"
+#include "fd-util.h"
+#include "fileio.h"
+#include "format-util.h"
+#include "fs-util.h"
+#include "hashmap.h"
+#include "id128-util.h"
+#include "macro.h"
+#include "missing_magic.h"
+#include "netlink-util.h"
+#include "parse-util.h"
+#include "path-util.h"
+#include "set.h"
+#include "socket-util.h"
+#include "stdio-util.h"
+#include "string-util.h"
+#include "strv.h"
+#include "strxcpyx.h"
+#include "user-util.h"
+#include "util.h"
+
+int device_new_aux(sd_device **ret) {
+ sd_device *device;
+
+ assert(ret);
+
+ device = new(sd_device, 1);
+ if (!device)
+ return -ENOMEM;
+
+ *device = (sd_device) {
+ .n_ref = 1,
+ .devmode = MODE_INVALID,
+ .devuid = UID_INVALID,
+ .devgid = GID_INVALID,
+ .action = _SD_DEVICE_ACTION_INVALID,
+ };
+
+ *ret = device;
+ return 0;
+}
+
+static sd_device *device_free(sd_device *device) {
+ assert(device);
+
+ sd_device_unref(device->parent);
+ free(device->syspath);
+ free(device->sysname);
+ free(device->devtype);
+ free(device->devname);
+ free(device->subsystem);
+ free(device->driver_subsystem);
+ free(device->driver);
+ free(device->device_id);
+ free(device->properties_strv);
+ free(device->properties_nulstr);
+
+ ordered_hashmap_free(device->properties);
+ ordered_hashmap_free(device->properties_db);
+ hashmap_free(device->sysattr_values);
+ set_free(device->sysattrs);
+ set_free(device->all_tags);
+ set_free(device->current_tags);
+ set_free(device->devlinks);
+ hashmap_free(device->children);
+
+ return mfree(device);
+}
+
+DEFINE_PUBLIC_TRIVIAL_REF_UNREF_FUNC(sd_device, sd_device, device_free);
+
+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) {
+ _unused_ _cleanup_free_ char *old_value = NULL;
+ _cleanup_free_ char *new_key = NULL, *new_value = NULL, *old_key = NULL;
+ int r;
+
+ r = ordered_hashmap_ensure_allocated(properties, &string_hash_ops_free_free);
+ if (r < 0)
+ return r;
+
+ new_key = strdup(key);
+ if (!new_key)
+ return -ENOMEM;
+
+ new_value = strdup(value);
+ if (!new_value)
+ return -ENOMEM;
+
+ old_value = ordered_hashmap_get2(*properties, key, (void**) &old_key);
+
+ /* ordered_hashmap_replace() does not fail when the hashmap already has the entry. */
+ r = ordered_hashmap_replace(*properties, new_key, new_value);
+ if (r < 0)
+ return r;
+
+ TAKE_PTR(new_key);
+ TAKE_PTR(new_value);
+ } else {
+ _unused_ _cleanup_free_ char *old_value = NULL;
+ _cleanup_free_ char *old_key = NULL;
+
+ old_value = ordered_hashmap_remove2(*properties, key, (void**) &old_key);
+ }
+
+ if (!db) {
+ device->properties_generation++;
+ device->properties_buf_outdated = true;
+ }
+
+ return 0;
+}
+
+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);
+
+ if (verify) {
+ _cleanup_close_ int fd = -1;
+
+ /* The input path maybe a symlink located outside of /sys. Let's try to chase the symlink at first.
+ * The primary usecase is that e.g. /proc/device-tree is a symlink to /sys/firmware/devicetree/base.
+ * By chasing symlinks in the path at first, we can call sd_device_new_from_path() with such path. */
+ r = chase_symlinks(_syspath, NULL, 0, &syspath, &fd);
+ if (r == -ENOENT)
+ /* the device does not exist (any more?) */
+ return log_debug_errno(SYNTHETIC_ERRNO(ENODEV),
+ "sd-device: Failed to chase symlinks in \"%s\".", _syspath);
+ if (r < 0)
+ return log_debug_errno(r, "sd-device: Failed to get target of '%s': %m", _syspath);
+
+ if (!path_startswith(syspath, "/sys")) {
+ _cleanup_free_ char *real_sys = NULL, *new_syspath = NULL;
+ char *p;
+
+ /* /sys is a symlink to somewhere sysfs is mounted on? In that case, we convert the path to real sysfs to "/sys". */
+ r = chase_symlinks("/sys", NULL, 0, &real_sys, NULL);
+ if (r < 0)
+ return log_debug_errno(r, "sd-device: Failed to chase symlink /sys: %m");
+
+ p = path_startswith(syspath, real_sys);
+ if (!p)
+ return log_debug_errno(SYNTHETIC_ERRNO(ENODEV),
+ "sd-device: Canonicalized path '%s' does not starts with sysfs mount point '%s'",
+ syspath, real_sys);
+
+ new_syspath = path_join("/sys", p);
+ if (!new_syspath)
+ return log_oom_debug();
+
+ free_and_replace(syspath, new_syspath);
+ path_simplify(syspath);
+ }
+
+ if (path_startswith(syspath, "/sys/devices/")) {
+ /* For proper devices, stricter rules apply: they must have a 'uevent' file,
+ * otherwise we won't allow them */
+
+ if (faccessat(fd, "uevent", F_OK, 0) < 0) {
+ if (errno == ENOENT)
+ /* This is not a valid device. Note, this condition is quite often
+ * satisfied when enumerating devices or finding a parent device.
+ * Hence, use log_trace_errno() here. */
+ return log_trace_errno(SYNTHETIC_ERRNO(ENODEV),
+ "sd-device: the uevent file \"%s/uevent\" does not exist.", syspath);
+ if (errno == ENOTDIR)
+ /* Not actually a directory. */
+ return log_debug_errno(SYNTHETIC_ERRNO(ENODEV),
+ "sd-device: the syspath \"%s\" is not a directory.", syspath);
+
+ return log_debug_errno(errno, "sd-device: cannot find uevent file for %s: %m", syspath);
+ }
+ } else {
+ struct stat st;
+
+ /* For everything else lax rules apply: they just need to be a directory */
+
+ if (fstat(fd, &st) < 0)
+ return log_debug_errno(errno, "sd-device: failed to check if syspath \"%s\" is a directory: %m", syspath);
+ if (!S_ISDIR(st.st_mode))
+ return log_debug_errno(SYNTHETIC_ERRNO(ENODEV),
+ "sd-device: the syspath \"%s\" is not a directory.", syspath);
+ }
+
+ /* Only operate on sysfs, i.e. refuse going down into /sys/fs/cgroup/ or similar places where
+ * things are not arranged as kobjects in kernel, and hence don't necessarily have
+ * kobject/attribute structure. */
+ r = getenv_bool_secure("SYSTEMD_DEVICE_VERIFY_SYSFS");
+ if (r < 0 && r != -ENXIO)
+ log_debug_errno(r, "Failed to parse $SYSTEMD_DEVICE_VERIFY_SYSFS value: %m");
+ if (r != 0) {
+ r = fd_is_fs_type(fd, SYSFS_MAGIC);
+ if (r < 0)
+ return log_debug_errno(r, "sd-device: failed to check if syspath \"%s\" is backed by sysfs.", syspath);
+ if (r == 0)
+ return log_debug_errno(SYNTHETIC_ERRNO(ENODEV),
+ "sd-device: the syspath \"%s\" is outside of sysfs, refusing.", syspath);
+ }
+ } else {
+ /* must be a subdirectory of /sys */
+ if (!path_startswith(_syspath, "/sys/"))
+ return log_debug_errno(SYNTHETIC_ERRNO(EINVAL),
+ "sd-device: Syspath '%s' is not a subdirectory of /sys",
+ _syspath);
+
+ syspath = strdup(_syspath);
+ if (!syspath)
+ return log_oom_debug();
+
+ path_simplify(syspath);
+ }
+
+ assert_se(devpath = startswith(syspath, "/sys"));
+ if (devpath[0] != '/')
+ return log_debug_errno(SYNTHETIC_ERRNO(ENODEV), "sd-device: \"/sys\" alone is not a valid device path.");
+
+ r = device_add_property_internal(device, "DEVPATH", devpath);
+ if (r < 0)
+ return log_debug_errno(r, "sd-device: Failed to add \"DEVPATH\" property for device \"%s\": %m", syspath);
+
+ free_and_replace(device->syspath, syspath);
+ device->devpath = devpath;
+ return 0;
+}
+
+static int device_new_from_syspath(sd_device **ret, const char *syspath, bool strict) {
+ _cleanup_(sd_device_unrefp) sd_device *device = NULL;
+ int r;
+
+ assert_return(ret, -EINVAL);
+ assert_return(syspath, -EINVAL);
+
+ if (strict && !path_startswith(syspath, "/sys/"))
+ return -EINVAL;
+
+ r = device_new_aux(&device);
+ if (r < 0)
+ return r;
+
+ r = device_set_syspath(device, syspath, /* verify= */ true);
+ if (r < 0)
+ return r;
+
+ *ret = TAKE_PTR(device);
+ return 0;
+}
+
+_public_ int sd_device_new_from_syspath(sd_device **ret, const char *syspath) {
+ return device_new_from_syspath(ret, syspath, /* strict = */ true);
+}
+
+int device_new_from_mode_and_devnum(sd_device **ret, mode_t mode, dev_t devnum) {
+ _cleanup_(sd_device_unrefp) sd_device *dev = NULL;
+ _cleanup_free_ char *syspath = NULL;
+ const char *t, *subsystem = NULL;
+ dev_t n;
+ int r;
+
+ assert(ret);
+
+ if (S_ISCHR(mode))
+ t = "char";
+ else if (S_ISBLK(mode))
+ t = "block";
+ else
+ return -ENOTTY;
+
+ if (major(devnum) == 0)
+ return -ENODEV;
+
+ if (asprintf(&syspath, "/sys/dev/%s/%u:%u", t, major(devnum), minor(devnum)) < 0)
+ return -ENOMEM;
+
+ r = sd_device_new_from_syspath(&dev, syspath);
+ if (r < 0)
+ return r;
+
+ r = sd_device_get_devnum(dev, &n);
+ if (r == -ENOENT)
+ return -ENXIO;
+ if (r < 0)
+ return r;
+ if (n != devnum)
+ return -ENXIO;
+
+ r = sd_device_get_subsystem(dev, &subsystem);
+ if (r < 0 && r != -ENOENT)
+ return r;
+ if (streq_ptr(subsystem, "block") != !!S_ISBLK(mode))
+ return -ENXIO;
+
+ *ret = TAKE_PTR(dev);
+ return 0;
+}
+
+_public_ int sd_device_new_from_devnum(sd_device **ret, char type, dev_t devnum) {
+ assert_return(ret, -EINVAL);
+ assert_return(IN_SET(type, 'b', 'c'), -EINVAL);
+
+ return device_new_from_mode_and_devnum(ret, type == 'b' ? S_IFBLK : S_IFCHR, devnum);
+}
+
+static int device_new_from_main_ifname(sd_device **ret, const char *ifname) {
+ const char *syspath;
+
+ assert(ret);
+ assert(ifname);
+
+ syspath = strjoina("/sys/class/net/", ifname);
+ return sd_device_new_from_syspath(ret, syspath);
+}
+
+_public_ int sd_device_new_from_ifname(sd_device **ret, const char *ifname) {
+ _cleanup_free_ char *main_name = NULL;
+ int r;
+
+ assert_return(ret, -EINVAL);
+ assert_return(ifname, -EINVAL);
+
+ r = parse_ifindex(ifname);
+ if (r > 0)
+ return sd_device_new_from_ifindex(ret, r);
+
+ if (ifname_valid(ifname)) {
+ r = device_new_from_main_ifname(ret, ifname);
+ if (r >= 0)
+ return r;
+ }
+
+ r = rtnl_resolve_link_alternative_name(NULL, ifname, &main_name);
+ if (r < 0)
+ return r;
+
+ return device_new_from_main_ifname(ret, main_name);
+}
+
+_public_ int sd_device_new_from_ifindex(sd_device **ret, int ifindex) {
+ _cleanup_(sd_device_unrefp) sd_device *dev = NULL;
+ char ifname[IF_NAMESIZE];
+ int r, i;
+
+ assert_return(ret, -EINVAL);
+ assert_return(ifindex > 0, -EINVAL);
+
+ if (format_ifname(ifindex, ifname) < 0)
+ return -ENODEV;
+
+ r = device_new_from_main_ifname(&dev, ifname);
+ if (r < 0)
+ return r;
+
+ r = sd_device_get_ifindex(dev, &i);
+ if (r == -ENOENT)
+ return -ENXIO;
+ if (r < 0)
+ return r;
+ if (i != ifindex)
+ return -ENXIO;
+
+ *ret = TAKE_PTR(dev);
+ return 0;
+}
+
+static int device_strjoin_new(
+ const char *a,
+ const char *b,
+ const char *c,
+ const char *d,
+ sd_device **ret) {
+
+ const char *p;
+ int r;
+
+ p = strjoina(a, b, c, d);
+ if (access(p, F_OK) < 0)
+ return IN_SET(errno, ENOENT, ENAMETOOLONG) ? 0 : -errno; /* If this sysfs is too long then it doesn't exist either */
+
+ r = sd_device_new_from_syspath(ret, p);
+ if (r < 0)
+ return r;
+
+ return 1;
+}
+
+_public_ int sd_device_new_from_subsystem_sysname(
+ sd_device **ret,
+ const char *subsystem,
+ const char *sysname) {
+
+ char *name;
+ int r;
+
+ assert_return(ret, -EINVAL);
+ assert_return(subsystem, -EINVAL);
+ assert_return(sysname, -EINVAL);
+
+ if (!path_is_normalized(subsystem))
+ return -EINVAL;
+ if (!path_is_normalized(sysname))
+ return -EINVAL;
+
+ /* translate sysname back to sysfs filename */
+ name = strdupa_safe(sysname);
+ string_replace_char(name, '/', '!');
+
+ if (streq(subsystem, "subsystem")) {
+ FOREACH_STRING(s, "/sys/bus/", "/sys/class/") {
+ r = device_strjoin_new(s, name, NULL, NULL, ret);
+ if (r < 0)
+ return r;
+ if (r > 0)
+ return 0;
+ }
+
+ } else if (streq(subsystem, "module")) {
+ r = device_strjoin_new("/sys/module/", name, NULL, NULL, ret);
+ if (r < 0)
+ return r;
+ if (r > 0)
+ return 0;
+
+ } else if (streq(subsystem, "drivers")) {
+ const char *sep;
+
+ sep = strchr(name, ':');
+ if (sep && sep[1] != '\0') { /* Require ":" and something non-empty after that. */
+
+ const char *subsys = memdupa_suffix0(name, sep - name);
+ sep++;
+
+ if (streq(sep, "drivers")) /* If the sysname is "drivers", then it's the drivers directory itself that is meant. */
+ r = device_strjoin_new("/sys/bus/", subsys, "/drivers", NULL, ret);
+ else
+ r = device_strjoin_new("/sys/bus/", subsys, "/drivers/", sep, ret);
+ if (r < 0)
+ return r;
+ if (r > 0)
+ return 0;
+ }
+ }
+
+ r = device_strjoin_new("/sys/bus/", subsystem, "/devices/", name, ret);
+ if (r < 0)
+ return r;
+ if (r > 0)
+ return 0;
+
+ r = device_strjoin_new("/sys/class/", subsystem, "/", name, ret);
+ if (r < 0)
+ return r;
+ if (r > 0)
+ return 0;
+
+ r = device_strjoin_new("/sys/firmware/", subsystem, "/", name, ret);
+ if (r < 0)
+ return r;
+ if (r > 0)
+ return 0;
+
+ return -ENODEV;
+}
+
+_public_ int sd_device_new_from_stat_rdev(sd_device **ret, const struct stat *st) {
+ assert_return(ret, -EINVAL);
+ assert_return(st, -EINVAL);
+
+ return device_new_from_mode_and_devnum(ret, st->st_mode, st->st_rdev);
+}
+
+_public_ int sd_device_new_from_devname(sd_device **ret, const char *devname) {
+ struct stat st;
+ dev_t devnum;
+ mode_t mode;
+
+ assert_return(ret, -EINVAL);
+ assert_return(devname, -EINVAL);
+
+ /* This function actually accepts both devlinks and devnames, i.e. both symlinks and device
+ * nodes below /dev/. */
+
+ /* Also ignore when the specified path is "/dev". */
+ if (isempty(path_startswith(devname, "/dev")))
+ return -EINVAL;
+
+ if (device_path_parse_major_minor(devname, &mode, &devnum) >= 0)
+ /* Let's shortcut when "/dev/block/maj:min" or "/dev/char/maj:min" is specified.
+ * In that case, we can directly convert the path to syspath, hence it is not necessary
+ * that the specified path exists. So, this works fine without udevd being running. */
+ return device_new_from_mode_and_devnum(ret, mode, devnum);
+
+ if (stat(devname, &st) < 0)
+ return ERRNO_IS_DEVICE_ABSENT(errno) ? -ENODEV : -errno;
+
+ return sd_device_new_from_stat_rdev(ret, &st);
+}
+
+_public_ int sd_device_new_from_path(sd_device **ret, const char *path) {
+ assert_return(ret, -EINVAL);
+ assert_return(path, -EINVAL);
+
+ if (path_startswith(path, "/dev"))
+ return sd_device_new_from_devname(ret, path);
+
+ return device_new_from_syspath(ret, path, /* strict = */ false);
+}
+
+int device_set_devtype(sd_device *device, const char *devtype) {
+ _cleanup_free_ char *t = NULL;
+ int r;
+
+ assert(device);
+ assert(devtype);
+
+ t = strdup(devtype);
+ if (!t)
+ return -ENOMEM;
+
+ r = device_add_property_internal(device, "DEVTYPE", t);
+ if (r < 0)
+ return r;
+
+ return free_and_replace(device->devtype, t);
+}
+
+int device_set_ifindex(sd_device *device, const char *name) {
+ int r, ifindex;
+
+ assert(device);
+ assert(name);
+
+ ifindex = parse_ifindex(name);
+ if (ifindex < 0)
+ return ifindex;
+
+ r = device_add_property_internal(device, "IFINDEX", name);
+ if (r < 0)
+ return r;
+
+ device->ifindex = ifindex;
+
+ return 0;
+}
+
+int device_set_devname(sd_device *device, const char *devname) {
+ _cleanup_free_ char *t = NULL;
+ int r;
+
+ assert(device);
+ assert(devname);
+
+ if (devname[0] != '/')
+ t = strjoin("/dev/", devname);
+ else
+ t = strdup(devname);
+ if (!t)
+ return -ENOMEM;
+
+ r = device_add_property_internal(device, "DEVNAME", t);
+ if (r < 0)
+ return r;
+
+ return free_and_replace(device->devname, t);
+}
+
+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, min = 0;
+ int r;
+
+ assert(device);
+ assert(major);
+
+ r = safe_atou(major, &maj);
+ if (r < 0)
+ return r;
+ if (maj == 0)
+ return 0;
+ if (!DEVICE_MAJOR_VALID(maj))
+ return -EINVAL;
+
+ if (minor) {
+ r = safe_atou(minor, &min);
+ if (r < 0)
+ return r;
+ if (!DEVICE_MINOR_VALID(min))
+ return -EINVAL;
+ }
+
+ 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;
+}
+
+int device_set_diskseq(sd_device *device, const char *str) {
+ uint64_t diskseq;
+ int r;
+
+ assert(device);
+ assert(str);
+
+ r = safe_atou64(str, &diskseq);
+ if (r < 0)
+ return r;
+ if (diskseq == 0)
+ return -EINVAL;
+
+ r = device_add_property_internal(device, "DISKSEQ", str);
+ if (r < 0)
+ return r;
+
+ device->diskseq = diskseq;
+
+ return 0;
+}
+
+static int handle_uevent_line(
+ sd_device *device,
+ const char *key,
+ const char *value,
+ const char **major,
+ const char **minor) {
+
+ assert(device);
+ assert(key);
+ assert(value);
+ assert(major);
+ assert(minor);
+
+ if (streq(key, "DEVTYPE"))
+ return device_set_devtype(device, value);
+ if (streq(key, "IFINDEX"))
+ return device_set_ifindex(device, value);
+ if (streq(key, "DEVNAME"))
+ return device_set_devname(device, value);
+ if (streq(key, "DEVMODE"))
+ return device_set_devmode(device, value);
+ if (streq(key, "DISKSEQ"))
+ return device_set_diskseq(device, value);
+ if (streq(key, "MAJOR"))
+ *major = value;
+ else if (streq(key, "MINOR"))
+ *minor = value;
+ else
+ return device_add_property_internal(device, key, value);
+
+ 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;
+ int r;
+
+ enum {
+ PRE_KEY,
+ KEY,
+ PRE_VALUE,
+ VALUE,
+ INVALID_LINE,
+ } state = PRE_KEY;
+
+ assert(device);
+
+ if (device->uevent_loaded || device->sealed)
+ return 0;
+
+ r = sd_device_get_syspath(device, &syspath);
+ if (r < 0)
+ return r;
+
+ device->uevent_loaded = true;
+
+ path = strjoina(syspath, "/uevent");
+
+ r = read_full_virtual_file(path, &uevent, &uevent_len);
+ if (r < 0) {
+ /* The uevent files may be write-only, the device may be already removed, or the device
+ * may not have the uevent file. */
+ if (r == -EACCES || ERRNO_IS_DEVICE_ABSENT(r))
+ return 0;
+
+ return log_device_debug_errno(device, r, "sd-device: Failed to read uevent file '%s': %m", path);
+ }
+
+ for (size_t 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_device_debug(device, "sd-device: Invalid uevent line '%s', ignoring", key);
+
+ state = PRE_KEY;
+ }
+
+ break;
+ case PRE_VALUE:
+ value = &uevent[i];
+ state = VALUE;
+
+ _fallthrough_; /* to handle empty property */
+ case VALUE:
+ if (strchr(NEWLINE, uevent[i])) {
+ uevent[i] = '\0';
+
+ r = handle_uevent_line(device, key, value, &major, &minor);
+ if (r < 0)
+ log_device_debug_errno(device, r, "sd-device: Failed to handle uevent entry '%s=%s', ignoring: %m", key, value);
+
+ state = PRE_KEY;
+ }
+
+ break;
+ default:
+ assert_not_reached();
+ }
+
+ if (major) {
+ r = device_set_devnum(device, major, minor);
+ if (r < 0)
+ log_device_debug_errno(device, r, "sd-device: Failed to set 'MAJOR=%s' or 'MINOR=%s' from '%s', ignoring: %m", major, strna(minor), path);
+ }
+
+ return 0;
+}
+
+_public_ int sd_device_get_ifindex(sd_device *device, int *ifindex) {
+ int r;
+
+ assert_return(device, -EINVAL);
+
+ r = device_read_uevent_file(device);
+ if (r < 0)
+ return r;
+
+ if (device->ifindex <= 0)
+ return -ENOENT;
+
+ if (ifindex)
+ *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': {
+ dev_t devt;
+
+ if (isempty(id))
+ return -EINVAL;
+
+ r = parse_devnum(id + 1, &devt);
+ if (r < 0)
+ return r;
+
+ return sd_device_new_from_devnum(ret, id[0], devt);
+ }
+
+ case 'n': {
+ int ifindex;
+
+ ifindex = parse_ifindex(id + 1);
+ if (ifindex < 0)
+ return ifindex;
+
+ return sd_device_new_from_ifindex(ret, ifindex);
+ }
+
+ case '+': {
+ const char *subsys, *sep;
+
+ sep = strchr(id + 1, ':');
+ if (!sep || sep - id - 1 > NAME_MAX)
+ return -EINVAL;
+
+ subsys = memdupa_suffix0(id + 1, sep - id - 1);
+
+ return sd_device_new_from_subsystem_sysname(ret, subsys, sep + 1);
+ }
+
+ default:
+ return -EINVAL;
+ }
+}
+
+_public_ int sd_device_get_syspath(sd_device *device, const char **ret) {
+ assert_return(device, -EINVAL);
+
+ assert(path_startswith(device->syspath, "/sys/"));
+
+ if (ret)
+ *ret = device->syspath;
+
+ return 0;
+}
+
+DEFINE_PRIVATE_HASH_OPS_FULL(
+ device_by_path_hash_ops,
+ char, path_hash_func, path_compare, free,
+ sd_device, sd_device_unref);
+
+static int device_enumerate_children_internal(sd_device *device, const char *subdir, Set **stack, Hashmap **children) {
+ _cleanup_closedir_ DIR *dir = NULL;
+ int r;
+
+ assert(device);
+ assert(stack);
+ assert(children);
+
+ r = device_opendir(device, subdir, &dir);
+ if (r < 0)
+ return r;
+
+ FOREACH_DIRENT_ALL(de, dir, return -errno) {
+ _cleanup_(sd_device_unrefp) sd_device *child = NULL;
+ _cleanup_free_ char *p = NULL;
+
+ if (dot_or_dot_dot(de->d_name))
+ continue;
+
+ if (!IN_SET(de->d_type, DT_LNK, DT_DIR))
+ continue;
+
+ if (subdir)
+ p = path_join(subdir, de->d_name);
+ else
+ p = strdup(de->d_name);
+ if (!p)
+ return -ENOMEM;
+
+ /* Try to create child device. */
+ r = sd_device_new_child(&child, device, p);
+ if (r >= 0) {
+ /* OK, this is a child device, saving it. */
+ r = hashmap_ensure_put(children, &device_by_path_hash_ops, p, child);
+ if (r < 0)
+ return r;
+
+ TAKE_PTR(p);
+ TAKE_PTR(child);
+ } else if (r == -ENODEV) {
+ /* This is not a child device. Push the sub-directory into stack, and read it later. */
+
+ if (de->d_type == DT_LNK)
+ /* Do not follow symlinks, otherwise, we will enter an infinite loop, e.g.,
+ * /sys/class/block/nvme0n1/subsystem/nvme0n1/subsystem/nvme0n1/subsystem/… */
+ continue;
+
+ r = set_ensure_consume(stack, &path_hash_ops_free, TAKE_PTR(p));
+ if (r < 0)
+ return r;
+ } else
+ return r;
+ }
+
+ return 0;
+}
+
+static int device_enumerate_children(sd_device *device) {
+ _cleanup_hashmap_free_ Hashmap *children = NULL;
+ _cleanup_set_free_ Set *stack = NULL;
+ int r;
+
+ assert(device);
+
+ if (device->children_enumerated)
+ return 0; /* Already enumerated. */
+
+ r = device_enumerate_children_internal(device, NULL, &stack, &children);
+ if (r < 0)
+ return r;
+
+ for (;;) {
+ _cleanup_free_ char *subdir = NULL;
+
+ subdir = set_steal_first(stack);
+ if (!subdir)
+ break;
+
+ r = device_enumerate_children_internal(device, subdir, &stack, &children);
+ if (r < 0)
+ return r;
+ }
+
+ device->children_enumerated = true;
+ device->children = TAKE_PTR(children);
+ return 1; /* Enumerated. */
+}
+
+_public_ sd_device *sd_device_get_child_first(sd_device *device, const char **ret_suffix) {
+ int r;
+
+ assert(device);
+
+ r = device_enumerate_children(device);
+ if (r < 0) {
+ log_device_debug_errno(device, r, "sd-device: failed to enumerate child devices: %m");
+ if (ret_suffix)
+ *ret_suffix = NULL;
+ return NULL;
+ }
+
+ device->children_iterator = ITERATOR_FIRST;
+
+ return sd_device_get_child_next(device, ret_suffix);
+}
+
+_public_ sd_device *sd_device_get_child_next(sd_device *device, const char **ret_suffix) {
+ sd_device *child;
+
+ assert(device);
+
+ hashmap_iterate(device->children, &device->children_iterator, (void**) &child, (const void**) ret_suffix);
+ return child;
+}
+
+_public_ int sd_device_new_child(sd_device **ret, sd_device *device, const char *suffix) {
+ _cleanup_free_ char *path = NULL;
+ sd_device *child;
+ const char *s;
+ int r;
+
+ assert_return(ret, -EINVAL);
+ assert_return(device, -EINVAL);
+ assert_return(suffix, -EINVAL);
+
+ if (!path_is_safe(suffix))
+ return -EINVAL;
+
+ /* If we have already enumerated children, try to find the child from the cache. */
+ child = hashmap_get(device->children, suffix);
+ if (child) {
+ *ret = sd_device_ref(child);
+ return 0;
+ }
+
+ r = sd_device_get_syspath(device, &s);
+ if (r < 0)
+ return r;
+
+ path = path_join(s, suffix);
+ if (!path)
+ return -ENOMEM;
+
+ return sd_device_new_from_syspath(ret, path);
+}
+
+static int device_new_from_child(sd_device **ret, sd_device *child) {
+ _cleanup_free_ char *path = NULL;
+ const char *syspath;
+ int r;
+
+ assert(ret);
+ assert(child);
+
+ r = sd_device_get_syspath(child, &syspath);
+ if (r < 0)
+ return r;
+
+ for (;;) {
+ _cleanup_free_ char *p = NULL;
+
+ r = path_extract_directory(path ?: syspath, &p);
+ if (r < 0)
+ return r;
+
+ if (path_equal(p, "/sys"))
+ return -ENODEV;
+
+ r = sd_device_new_from_syspath(ret, p);
+ if (r != -ENODEV)
+ return r;
+
+ free_and_replace(path, p);
+ }
+}
+
+_public_ int sd_device_get_parent(sd_device *child, sd_device **ret) {
+ int r;
+
+ assert_return(child, -EINVAL);
+
+ if (!child->parent_set) {
+ r = device_new_from_child(&child->parent, child);
+ if (r < 0 && r != -ENODEV)
+ return r;
+
+ child->parent_set = true;
+ }
+
+ if (!child->parent)
+ return -ENOENT;
+
+ if (ret)
+ *ret = child->parent;
+ return 0;
+}
+
+int device_set_subsystem(sd_device *device, const char *subsystem) {
+ _cleanup_free_ char *s = NULL;
+ int r;
+
+ assert(device);
+
+ if (subsystem) {
+ s = strdup(subsystem);
+ if (!s)
+ return -ENOMEM;
+ }
+
+ r = device_add_property_internal(device, "SUBSYSTEM", s);
+ if (r < 0)
+ return r;
+
+ device->subsystem_set = true;
+ return free_and_replace(device->subsystem, s);
+}
+
+int device_set_drivers_subsystem(sd_device *device) {
+ _cleanup_free_ char *subsystem = NULL;
+ const char *devpath, *drivers, *p;
+ int r;
+
+ assert(device);
+
+ r = sd_device_get_devpath(device, &devpath);
+ if (r < 0)
+ return r;
+
+ drivers = strstr(devpath, "/drivers/");
+ if (!drivers)
+ drivers = endswith(devpath, "/drivers");
+ if (!drivers)
+ return -EINVAL;
+
+ /* Find the path component immediately before the "/drivers/" string */
+ r = path_find_last_component(devpath, /* accept_dot_dot= */ false, &drivers, &p);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ return -EINVAL;
+
+ subsystem = strndup(p, r);
+ if (!subsystem)
+ return -ENOMEM;
+
+ r = device_set_subsystem(device, "drivers");
+ if (r < 0)
+ return r;
+
+ return free_and_replace(device->driver_subsystem, subsystem);
+}
+
+_public_ int sd_device_get_subsystem(sd_device *device, const char **ret) {
+ int r;
+
+ assert_return(device, -EINVAL);
+
+ if (!device->subsystem_set) {
+ _cleanup_free_ char *subsystem = NULL;
+ const char *syspath;
+ char *path;
+
+ r = sd_device_get_syspath(device, &syspath);
+ if (r < 0)
+ return r;
+
+ /* read 'subsystem' link */
+ path = strjoina(syspath, "/subsystem");
+ r = readlink_value(path, &subsystem);
+ if (r < 0 && r != -ENOENT)
+ return log_device_debug_errno(device, r,
+ "sd-device: Failed to read subsystem for %s: %m",
+ device->devpath);
+
+ if (subsystem)
+ r = device_set_subsystem(device, subsystem);
+ /* use implicit names */
+ else if (!isempty(path_startswith(device->devpath, "/module/")))
+ r = device_set_subsystem(device, "module");
+ else if (strstr(syspath, "/drivers/") || endswith(syspath, "/drivers"))
+ r = device_set_drivers_subsystem(device);
+ else if (!isempty(PATH_STARTSWITH_SET(device->devpath, "/class/", "/bus/")))
+ r = device_set_subsystem(device, "subsystem");
+ else {
+ device->subsystem_set = true;
+ r = 0;
+ }
+ if (r < 0)
+ return log_device_debug_errno(device, r,
+ "sd-device: Failed to set subsystem for %s: %m",
+ device->devpath);
+ }
+
+ if (!device->subsystem)
+ return -ENOENT;
+
+ if (ret)
+ *ret = device->subsystem;
+ return 0;
+}
+
+_public_ int sd_device_get_devtype(sd_device *device, const char **devtype) {
+ int r;
+
+ assert_return(device, -EINVAL);
+
+ r = device_read_uevent_file(device);
+ if (r < 0)
+ return r;
+
+ if (!device->devtype)
+ return -ENOENT;
+
+ if (devtype)
+ *devtype = device->devtype;
+
+ return !!device->devtype;
+}
+
+_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;
+
+ (void) sd_device_get_subsystem(parent, &parent_subsystem);
+ if (streq_ptr(parent_subsystem, subsystem)) {
+ const char *parent_devtype = NULL;
+
+ 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;
+
+ if (ret)
+ *ret = parent;
+ return 0;
+}
+
+_public_ int sd_device_get_devnum(sd_device *device, dev_t *devnum) {
+ int r;
+
+ assert_return(device, -EINVAL);
+
+ r = device_read_uevent_file(device);
+ if (r < 0)
+ return r;
+
+ if (major(device->devnum) <= 0)
+ return -ENOENT;
+
+ if (devnum)
+ *devnum = device->devnum;
+
+ return 0;
+}
+
+int device_set_driver(sd_device *device, const char *driver) {
+ _cleanup_free_ char *d = NULL;
+ int r;
+
+ assert(device);
+
+ if (driver) {
+ d = strdup(driver);
+ if (!d)
+ return -ENOMEM;
+ }
+
+ r = device_add_property_internal(device, "DRIVER", d);
+ if (r < 0)
+ return r;
+
+ device->driver_set = true;
+ return free_and_replace(device->driver, d);
+}
+
+_public_ int sd_device_get_driver(sd_device *device, const char **ret) {
+ assert_return(device, -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 != -ENOENT)
+ return log_device_debug_errno(device, r,
+ "sd-device: readlink(\"%s\") failed: %m", path);
+
+ r = device_set_driver(device, driver);
+ if (r < 0)
+ return log_device_debug_errno(device, r,
+ "sd-device: Failed to set driver \"%s\": %m", driver);
+ }
+
+ if (!device->driver)
+ return -ENOENT;
+
+ if (ret)
+ *ret = device->driver;
+ return 0;
+}
+
+_public_ int sd_device_get_devpath(sd_device *device, const char **ret) {
+ assert_return(device, -EINVAL);
+
+ assert(device->devpath);
+ assert(device->devpath[0] == '/');
+
+ if (ret)
+ *ret = device->devpath;
+
+ return 0;
+}
+
+_public_ int sd_device_get_devname(sd_device *device, const char **devname) {
+ int r;
+
+ assert_return(device, -EINVAL);
+
+ r = device_read_uevent_file(device);
+ if (r < 0)
+ return r;
+
+ if (!device->devname)
+ return -ENOENT;
+
+ assert(path_startswith(device->devname, "/dev/"));
+
+ if (devname)
+ *devname = device->devname;
+ return 0;
+}
+
+static int device_set_sysname_and_sysnum(sd_device *device) {
+ _cleanup_free_ char *sysname = NULL;
+ size_t len, n;
+ int r;
+
+ assert(device);
+
+ r = path_extract_filename(device->devpath, &sysname);
+ if (r < 0)
+ return r;
+ if (r == O_DIRECTORY)
+ return -EINVAL;
+
+ /* some devices have '!' in their name, change that to '/' */
+ string_replace_char(sysname, '!', '/');
+
+ n = strspn_from_end(sysname, DIGITS);
+ len = strlen(sysname);
+ assert(n <= len);
+ if (n == len)
+ n = 0; /* Do not set sysnum for number only sysname. */
+
+ device->sysnum = n > 0 ? sysname + len - n : NULL;
+ return free_and_replace(device->sysname, sysname);
+}
+
+_public_ int sd_device_get_sysname(sd_device *device, const char **ret) {
+ int r;
+
+ assert_return(device, -EINVAL);
+
+ if (!device->sysname) {
+ r = device_set_sysname_and_sysnum(device);
+ if (r < 0)
+ return r;
+ }
+
+ if (ret)
+ *ret = device->sysname;
+ return 0;
+}
+
+_public_ int sd_device_get_sysnum(sd_device *device, const char **ret) {
+ int r;
+
+ assert_return(device, -EINVAL);
+
+ if (!device->sysname) {
+ r = device_set_sysname_and_sysnum(device);
+ if (r < 0)
+ return r;
+ }
+
+ if (!device->sysnum)
+ return -ENOENT;
+
+ if (ret)
+ *ret = device->sysnum;
+ return 0;
+}
+
+_public_ int sd_device_get_action(sd_device *device, sd_device_action_t *ret) {
+ assert_return(device, -EINVAL);
+
+ if (device->action < 0)
+ return -ENOENT;
+
+ if (ret)
+ *ret = device->action;
+
+ return 0;
+}
+
+_public_ int sd_device_get_seqnum(sd_device *device, uint64_t *ret) {
+ assert_return(device, -EINVAL);
+
+ if (device->seqnum == 0)
+ return -ENOENT;
+
+ if (ret)
+ *ret = device->seqnum;
+
+ return 0;
+}
+
+_public_ int sd_device_get_diskseq(sd_device *device, uint64_t *ret) {
+ int r;
+
+ assert_return(device, -EINVAL);
+
+ r = device_read_uevent_file(device);
+ if (r < 0)
+ return r;
+
+ if (device->diskseq == 0)
+ return -ENOENT;
+
+ if (ret)
+ *ret = device->diskseq;
+
+ 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, bool both) {
+ int r, added;
+
+ assert(device);
+ assert(tag);
+
+ if (!is_valid_tag(tag))
+ return -EINVAL;
+
+ /* Definitely add to the "all" list of tags (i.e. the sticky list) */
+ added = set_put_strdup(&device->all_tags, tag);
+ if (added < 0)
+ return added;
+
+ /* And optionally, also add it to the current list of tags */
+ if (both) {
+ r = set_put_strdup(&device->current_tags, tag);
+ if (r < 0) {
+ if (added > 0)
+ (void) set_remove(device->all_tags, tag);
+
+ 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_put_strdup(&device->devlinks, devlink);
+ if (r < 0)
+ return r;
+
+ device->devlinks_generation++;
+ device->property_devlinks_outdated = true;
+
+ return 0;
+}
+
+bool device_has_devlink(sd_device *device, const char *devlink) {
+ assert(device);
+ assert(devlink);
+
+ return set_contains(device->devlinks, devlink);
+}
+
+static int device_add_property_internal_from_string(sd_device *device, const char *str) {
+ _cleanup_free_ char *key = NULL;
+ char *value;
+ int r;
+
+ 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;
+
+ /* Add the property to both sd_device::properties and sd_device::properties_db,
+ * as this is called by only handle_db_line(). */
+ r = device_add_property_aux(device, key, value, false);
+ if (r < 0)
+ return r;
+
+ return device_add_property_aux(device, key, value, true);
+}
+
+int device_set_usec_initialized(sd_device *device, usec_t when) {
+ char s[DECIMAL_STR_MAX(usec_t)];
+ int r;
+
+ assert(device);
+
+ xsprintf(s, USEC_FMT, when);
+
+ r = device_add_property_internal(device, "USEC_INITIALIZED", s);
+ if (r < 0)
+ return r;
+
+ device->usec_initialized = when;
+ return 0;
+}
+
+static int handle_db_line(sd_device *device, char key, const char *value) {
+ int r;
+
+ assert(device);
+ assert(value);
+
+ switch (key) {
+ case 'G': /* Any tag */
+ case 'Q': /* Current tag */
+ return device_add_tag(device, value, key == 'Q');
+
+ case 'S': {
+ const char *path;
+
+ path = strjoina("/dev/", value);
+ return device_add_devlink(device, path);
+ }
+ case 'E':
+ return device_add_property_internal_from_string(device, value);
+
+ case 'I': {
+ usec_t t;
+
+ r = safe_atou64(value, &t);
+ if (r < 0)
+ return r;
+
+ return device_set_usec_initialized(device, t);
+ }
+ case 'L':
+ return safe_atoi(value, &device->devlink_priority);
+
+ case 'W':
+ /* Deprecated. Previously, watch handle is both saved in database and /run/udev/watch.
+ * However, the handle saved in database may not be updated when the handle is updated
+ * or removed. Moreover, it is not necessary to store the handle within the database,
+ * as its value becomes meaningless when udevd is restarted. */
+ return 0;
+
+ case 'V':
+ return safe_atou(value, &device->database_version);
+
+ default:
+ log_device_debug(device, "sd-device: Unknown key '%c' in device db, ignoring", key);
+ return 0;
+ }
+}
+
+int device_get_device_id(sd_device *device, const char **ret) {
+ assert(device);
+ assert(ret);
+
+ if (!device->device_id) {
+ _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;
+
+ if (sd_device_get_devnum(device, &devnum) >= 0) {
+ /* use dev_t — b259:131072, c254:0 */
+ if (asprintf(&id, "%c%u:%u",
+ streq(subsystem, "block") ? 'b' : 'c',
+ major(devnum), minor(devnum)) < 0)
+ return -ENOMEM;
+ } else if (sd_device_get_ifindex(device, &ifindex) >= 0) {
+ /* use netdev ifindex — n3 */
+ if (asprintf(&id, "n%u", (unsigned) ifindex) < 0)
+ return -ENOMEM;
+ } else {
+ _cleanup_free_ char *sysname = NULL;
+
+ /* use $subsys:$sysname — pci:0000:00:1f.2
+ * sd_device_get_sysname() has '!' translated, get it from devpath */
+ r = path_extract_filename(device->devpath, &sysname);
+ if (r < 0)
+ return r;
+ if (r == O_DIRECTORY)
+ return -EINVAL;
+
+ if (streq(subsystem, "drivers")) {
+ /* the 'drivers' pseudo-subsystem is special, and needs the real
+ * subsystem encoded as well */
+ assert(device->driver_subsystem);
+ id = strjoin("+drivers:", device->driver_subsystem, ":", sysname);
+ } else
+ id = strjoin("+", subsystem, ":", sysname);
+ if (!id)
+ return -ENOMEM;
+ }
+
+ if (!filename_is_valid(id))
+ return -EINVAL;
+
+ device->device_id = TAKE_PTR(id);
+ }
+
+ *ret = device->device_id;
+ return 0;
+}
+
+int device_read_db_internal_filename(sd_device *device, const char *filename) {
+ _cleanup_free_ char *db = NULL;
+ const char *value;
+ size_t db_len;
+ char key = '\0'; /* Unnecessary initialization to appease gcc-12.0.0-0.4.fc36 */
+ int r;
+
+ enum {
+ PRE_KEY,
+ KEY,
+ PRE_VALUE,
+ VALUE,
+ INVALID_LINE,
+ } state = PRE_KEY;
+
+ assert(device);
+ assert(filename);
+
+ r = read_full_file(filename, &db, &db_len);
+ if (r < 0) {
+ if (r == -ENOENT)
+ return 0;
+
+ return log_device_debug_errno(device, r, "sd-device: Failed to read db '%s': %m", filename);
+ }
+
+ /* devices with a database entry are initialized */
+ device->is_initialized = true;
+
+ device->db_loaded = true;
+
+ for (size_t 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_device_debug(device, "sd-device: Invalid db entry with key '%c', ignoring", 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_device_debug_errno(device, r, "sd-device: Failed to handle db entry '%c:%s', ignoring: %m",
+ key, value);
+
+ state = PRE_KEY;
+ }
+
+ break;
+ default:
+ return log_device_debug_errno(device, SYNTHETIC_ERRNO(EINVAL), "sd-device: invalid db syntax.");
+ }
+
+ return 0;
+}
+
+int device_read_db_internal(sd_device *device, bool force) {
+ const char *id, *path;
+ int r;
+
+ assert(device);
+
+ if (device->db_loaded || (!force && device->sealed))
+ return 0;
+
+ r = device_get_device_id(device, &id);
+ if (r < 0)
+ return r;
+
+ path = strjoina("/run/udev/data/", id);
+
+ return device_read_db_internal_filename(device, path);
+}
+
+_public_ int sd_device_get_is_initialized(sd_device *device) {
+ int r;
+
+ assert_return(device, -EINVAL);
+
+ r = device_read_db(device);
+ if (r == -ENOENT)
+ /* The device may be already removed or renamed. */
+ return false;
+ if (r < 0)
+ return r;
+
+ return device->is_initialized;
+}
+
+_public_ int sd_device_get_usec_initialized(sd_device *device, uint64_t *ret) {
+ int r;
+
+ assert_return(device, -EINVAL);
+
+ r = sd_device_get_is_initialized(device);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ return -EBUSY;
+
+ if (device->usec_initialized == 0)
+ return -ENODATA;
+
+ if (ret)
+ *ret = device->usec_initialized;
+
+ return 0;
+}
+
+_public_ int sd_device_get_usec_since_initialized(sd_device *device, uint64_t *ret) {
+ usec_t now_ts, ts;
+ int r;
+
+ assert_return(device, -EINVAL);
+
+ r = sd_device_get_usec_initialized(device, &ts);
+ if (r < 0)
+ return r;
+
+ now_ts = now(CLOCK_MONOTONIC);
+
+ if (now_ts < ts)
+ return -EIO;
+
+ if (ret)
+ *ret = usec_sub_unsigned(now_ts, ts);
+
+ 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->all_tags_iterator_generation = device->tags_generation;
+ device->all_tags_iterator = ITERATOR_FIRST;
+
+ (void) set_iterate(device->all_tags, &device->all_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->all_tags_iterator_generation != device->tags_generation)
+ return NULL;
+
+ (void) set_iterate(device->all_tags, &device->all_tags_iterator, &v);
+ return v;
+}
+
+static bool device_database_supports_current_tags(sd_device *device) {
+ assert(device);
+
+ (void) device_read_db(device);
+
+ /* The current tags (saved in Q field) feature is implemented in database version 1.
+ * If the database version is 0, then the tags (NOT current tags, saved in G field) are not
+ * sticky. Thus, we can safely bypass the operations for the current tags (Q) to tags (G). */
+
+ return device->database_version >= 1;
+}
+
+_public_ const char *sd_device_get_current_tag_first(sd_device *device) {
+ void *v;
+
+ assert_return(device, NULL);
+
+ if (!device_database_supports_current_tags(device))
+ return sd_device_get_tag_first(device);
+
+ (void) device_read_db(device);
+
+ device->current_tags_iterator_generation = device->tags_generation;
+ device->current_tags_iterator = ITERATOR_FIRST;
+
+ (void) set_iterate(device->current_tags, &device->current_tags_iterator, &v);
+ return v;
+}
+
+_public_ const char *sd_device_get_current_tag_next(sd_device *device) {
+ void *v;
+
+ assert_return(device, NULL);
+
+ if (!device_database_supports_current_tags(device))
+ return sd_device_get_tag_next(device);
+
+ (void) device_read_db(device);
+
+ if (device->current_tags_iterator_generation != device->tags_generation)
+ return NULL;
+
+ (void) set_iterate(device->current_tags, &device->current_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;
+}
+
+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;
+
+ r = set_strjoin(device->devlinks, " ", false, &devlinks);
+ if (r < 0)
+ return r;
+
+ if (!isempty(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;
+
+ r = set_strjoin(device->all_tags, ":", true, &tags);
+ if (r < 0)
+ return r;
+
+ if (!isempty(tags)) {
+ r = device_add_property_internal(device, "TAGS", tags);
+ if (r < 0)
+ return r;
+ }
+
+ tags = mfree(tags);
+ r = set_strjoin(device->current_tags, ":", true, &tags);
+ if (r < 0)
+ return r;
+
+ if (!isempty(tags)) {
+ r = device_add_property_internal(device, "CURRENT_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;
+ 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;
+
+ (void) ordered_hashmap_iterate(device->properties, &device->properties_iterator, (void**)_value, (const void**)&key);
+ return key;
+}
+
+_public_ const char *sd_device_get_property_next(sd_device *device, const char **_value) {
+ const char *key;
+ 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;
+
+ (void) ordered_hashmap_iterate(device->properties, &device->properties_iterator, (void**)_value, (const void**)&key);
+ return key;
+}
+
+static int device_sysattrs_read_all_internal(sd_device *device, const char *subdir, Set **stack) {
+ _cleanup_closedir_ DIR *dir = NULL;
+ int r;
+
+ assert(device);
+ assert(stack);
+
+ r = device_opendir(device, subdir, &dir);
+ if (r == -ENOENT && subdir)
+ return 0; /* Maybe, this is a child device, and is already removed. */
+ if (r < 0)
+ return r;
+
+ if (subdir) {
+ if (faccessat(dirfd(dir), "uevent", F_OK, 0) >= 0)
+ return 0; /* this is a child device, skipping */
+ if (errno != ENOENT) {
+ log_device_debug_errno(device, errno,
+ "sd-device: Failed to access %s/uevent, ignoring sub-directory %s: %m",
+ subdir, subdir);
+ return 0;
+ }
+ }
+
+ FOREACH_DIRENT_ALL(de, dir, return -errno) {
+ _cleanup_free_ char *p = NULL;
+ struct stat statbuf;
+
+ if (dot_or_dot_dot(de->d_name))
+ continue;
+
+ /* only handle symlinks, regular files, and directories */
+ if (!IN_SET(de->d_type, DT_LNK, DT_REG, DT_DIR))
+ continue;
+
+ if (subdir) {
+ p = path_join(subdir, de->d_name);
+ if (!p)
+ return -ENOMEM;
+ }
+
+ if (de->d_type == DT_DIR) {
+ /* push the sub-directory into the stack, and read it later. */
+ if (p)
+ r = set_ensure_consume(stack, &path_hash_ops_free, TAKE_PTR(p));
+ else
+ r = set_put_strdup_full(stack, &path_hash_ops_free, de->d_name);
+ if (r < 0)
+ return r;
+
+ continue;
+ }
+
+ if (fstatat(dirfd(dir), de->d_name, &statbuf, AT_SYMLINK_NOFOLLOW) < 0)
+ continue;
+
+ if ((statbuf.st_mode & (S_IRUSR | S_IWUSR)) == 0)
+ continue;
+
+ if (p)
+ r = set_ensure_consume(&device->sysattrs, &path_hash_ops_free, TAKE_PTR(p));
+ else
+ r = set_put_strdup_full(&device->sysattrs, &path_hash_ops_free, de->d_name);
+ if (r < 0)
+ return r;
+ }
+
+ return 0;
+}
+
+static int device_sysattrs_read_all(sd_device *device) {
+ _cleanup_set_free_ Set *stack = NULL;
+ int r;
+
+ assert(device);
+
+ if (device->sysattrs_read)
+ return 0;
+
+ r = device_sysattrs_read_all_internal(device, NULL, &stack);
+ if (r < 0)
+ return r;
+
+ for (;;) {
+ _cleanup_free_ char *subdir = NULL;
+
+ subdir = set_steal_first(stack);
+ if (!subdir)
+ break;
+
+ r = device_sysattrs_read_all_internal(device, subdir, &stack);
+ 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->all_tags, tag);
+}
+
+_public_ int sd_device_has_current_tag(sd_device *device, const char *tag) {
+ assert_return(device, -EINVAL);
+ assert_return(tag, -EINVAL);
+
+ if (!device_database_supports_current_tags(device))
+ return sd_device_has_tag(device, tag);
+
+ (void) device_read_db(device);
+
+ return set_contains(device->current_tags, tag);
+}
+
+_public_ int sd_device_get_property_value(sd_device *device, const char *key, const char **ret_value) {
+ const char *value;
+ int r;
+
+ assert_return(device, -EINVAL);
+ assert_return(key, -EINVAL);
+
+ r = device_properties_prepare(device);
+ if (r < 0)
+ return r;
+
+ value = ordered_hashmap_get(device->properties, key);
+ if (!value)
+ return -ENOENT;
+
+ if (ret_value)
+ *ret_value = value;
+ return 0;
+}
+
+int device_get_property_bool(sd_device *device, const char *key) {
+ const char *value;
+ int r;
+
+ assert(device);
+ assert(key);
+
+ r = sd_device_get_property_value(device, key, &value);
+ if (r < 0)
+ return r;
+
+ return parse_boolean(value);
+}
+
+_public_ int sd_device_get_trigger_uuid(sd_device *device, sd_id128_t *ret) {
+ const char *s;
+ sd_id128_t id;
+ int r;
+
+ assert_return(device, -EINVAL);
+
+ /* Retrieves the UUID attached to a uevent when triggering it from userspace via
+ * sd_device_trigger_with_uuid() or an equivalent interface. Returns -ENOENT if the record is not
+ * caused by a synthetic event and -ENODATA if it was but no UUID was specified */
+
+ r = sd_device_get_property_value(device, "SYNTH_UUID", &s);
+ if (r < 0)
+ return r;
+
+ if (streq(s, "0")) /* SYNTH_UUID=0 is set whenever a device is triggered by userspace without specifying a UUID */
+ return -ENODATA;
+
+ r = sd_id128_from_string(s, &id);
+ if (r < 0)
+ return r;
+
+ if (ret)
+ *ret = id;
+
+ return 0;
+}
+
+void device_clear_sysattr_cache(sd_device *device) {
+ device->sysattr_values = hashmap_free(device->sysattr_values);
+}
+
+int device_cache_sysattr_value(sd_device *device, const char *key, char *value) {
+ _unused_ _cleanup_free_ char *old_value = NULL;
+ _cleanup_free_ char *new_key = NULL;
+ int r;
+
+ assert(device);
+ assert(key);
+
+ /* This takes the reference of the input value. The input value may be NULL.
+ * This replaces the value if it already exists. */
+
+ /* First, remove the old cache entry. So, we do not need to clear cache on error. */
+ old_value = hashmap_remove2(device->sysattr_values, key, (void **) &new_key);
+ if (!new_key) {
+ new_key = strdup(key);
+ if (!new_key)
+ return -ENOMEM;
+ }
+
+ r = hashmap_ensure_put(&device->sysattr_values, &string_hash_ops_free_free, new_key, value);
+ if (r < 0)
+ return r;
+
+ TAKE_PTR(new_key);
+
+ return 0;
+}
+
+int device_get_cached_sysattr_value(sd_device *device, const char *key, const char **ret_value) {
+ const char *k = NULL, *value;
+
+ assert(device);
+ assert(key);
+
+ value = hashmap_get2(device->sysattr_values, key, (void **) &k);
+ if (!k)
+ return -ESTALE; /* We have not read the attribute. */
+ if (!value)
+ return -ENOENT; /* We have looked up the attribute before and it did not exist. */
+ if (ret_value)
+ *ret_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 **ret_value) {
+ _cleanup_free_ char *value = NULL, *path = NULL;
+ const char *syspath;
+ struct stat statbuf;
+ int r;
+
+ assert_return(device, -EINVAL);
+ assert_return(sysattr, -EINVAL);
+
+ /* look for possibly already cached result */
+ r = device_get_cached_sysattr_value(device, sysattr, ret_value);
+ if (r != -ESTALE)
+ return r;
+
+ r = sd_device_get_syspath(device, &syspath);
+ if (r < 0)
+ return r;
+
+ path = path_join(syspath, sysattr);
+ if (!path)
+ return -ENOMEM;
+
+ if (lstat(path, &statbuf) < 0) {
+ int k;
+
+ r = -errno;
+
+ /* remember that we could not access the sysattr */
+ k = device_cache_sysattr_value(device, sysattr, NULL);
+ if (k < 0)
+ log_device_debug_errno(device, k,
+ "sd-device: failed to cache attribute '%s' with NULL, ignoring: %m",
+ sysattr);
+
+ return r;
+ } 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 -EISDIR;
+ else if (!(statbuf.st_mode & S_IRUSR))
+ /* skip non-readable files */
+ return -EPERM;
+ else {
+ size_t size;
+
+ /* Read attribute value, Some attributes contain embedded '\0'. So, it is necessary to
+ * also get the size of the result. See issue #20025. */
+ r = read_full_virtual_file(path, &value, &size);
+ if (r < 0)
+ return r;
+
+ /* drop trailing newlines */
+ while (size > 0 && strchr(NEWLINE, value[--size]))
+ value[size] = '\0';
+ }
+
+ /* Unfortunately, we need to return 'const char*' instead of 'char*'. Hence, failure in caching
+ * sysattr value is critical unlike the other places. */
+ r = device_cache_sysattr_value(device, sysattr, value);
+ if (r < 0) {
+ log_device_debug_errno(device, r,
+ "sd-device: failed to cache attribute '%s' with '%s'%s: %m",
+ sysattr, value, ret_value ? "" : ", ignoring");
+ if (ret_value)
+ return r;
+
+ return 0;
+ }
+
+ if (ret_value)
+ *ret_value = value;
+
+ TAKE_PTR(value);
+ return 0;
+}
+
+int device_get_sysattr_int(sd_device *device, const char *sysattr, int *ret_value) {
+ const char *value;
+ int r;
+
+ r = sd_device_get_sysattr_value(device, sysattr, &value);
+ if (r < 0)
+ return r;
+
+ int v;
+ r = safe_atoi(value, &v);
+ if (r < 0)
+ return log_device_debug_errno(device, r, "Failed to parse '%s' attribute: %m", sysattr);
+
+ if (ret_value)
+ *ret_value = v;
+ /* We return "true" if the value is positive. */
+ return v > 0;
+}
+
+int device_get_sysattr_unsigned(sd_device *device, const char *sysattr, unsigned *ret_value) {
+ const char *value;
+ int r;
+
+ r = sd_device_get_sysattr_value(device, sysattr, &value);
+ if (r < 0)
+ return r;
+
+ unsigned v;
+ r = safe_atou(value, &v);
+ if (r < 0)
+ return log_device_debug_errno(device, r, "Failed to parse '%s' attribute: %m", sysattr);
+
+ if (ret_value)
+ *ret_value = v;
+ /* We return "true" if the value is positive. */
+ return v > 0;
+}
+
+int device_get_sysattr_bool(sd_device *device, const char *sysattr) {
+ const char *value;
+ int r;
+
+ assert(device);
+ assert(sysattr);
+
+ r = sd_device_get_sysattr_value(device, sysattr, &value);
+ if (r < 0)
+ return r;
+
+ return parse_boolean(value);
+}
+
+static void device_remove_cached_sysattr_value(sd_device *device, const char *_key) {
+ _cleanup_free_ char *key = NULL;
+
+ assert(device);
+ assert(_key);
+
+ free(hashmap_remove2(device->sysattr_values, _key, (void **) &key));
+}
+
+_public_ int sd_device_set_sysattr_value(sd_device *device, const char *sysattr, const char *_value) {
+ _cleanup_free_ char *value = NULL, *path = NULL;
+ const char *syspath;
+ size_t len;
+ int r;
+
+ assert_return(device, -EINVAL);
+ assert_return(sysattr, -EINVAL);
+
+ /* Set the attribute and save it in the cache. */
+
+ if (!_value) {
+ /* If input value is NULL, then clear cache and not write anything. */
+ device_remove_cached_sysattr_value(device, sysattr);
+ return 0;
+ }
+
+ r = sd_device_get_syspath(device, &syspath);
+ if (r < 0)
+ return r;
+
+ path = path_join(syspath, sysattr);
+ if (!path)
+ return -ENOMEM;
+
+ len = strlen(_value);
+
+ /* drop trailing newlines */
+ while (len > 0 && strchr(NEWLINE, _value[len - 1]))
+ len --;
+
+ /* value length is limited to 4k */
+ if (len > 4096)
+ return -EINVAL;
+
+ value = strndup(_value, len);
+ if (!value)
+ return -ENOMEM;
+
+ r = write_string_file(path, value, WRITE_STRING_FILE_DISABLE_BUFFER | WRITE_STRING_FILE_NOFOLLOW);
+ if (r < 0) {
+ /* On failure, clear cache entry, as we do not know how it fails. */
+ device_remove_cached_sysattr_value(device, sysattr);
+ return r;
+ }
+
+ /* Do not cache action string written into uevent file. */
+ if (streq(sysattr, "uevent"))
+ return 0;
+
+ r = device_cache_sysattr_value(device, sysattr, value);
+ if (r < 0)
+ log_device_debug_errno(device, r,
+ "sd-device: failed to cache attribute '%s' with '%s', ignoring: %m",
+ sysattr, value);
+ else
+ TAKE_PTR(value);
+
+ return 0;
+}
+
+_public_ int sd_device_set_sysattr_valuef(sd_device *device, const char *sysattr, const char *format, ...) {
+ _cleanup_free_ char *value = NULL;
+ va_list ap;
+ int r;
+
+ assert_return(device, -EINVAL);
+ assert_return(sysattr, -EINVAL);
+
+ if (!format) {
+ device_remove_cached_sysattr_value(device, sysattr);
+ return 0;
+ }
+
+ va_start(ap, format);
+ r = vasprintf(&value, format, ap);
+ va_end(ap);
+
+ if (r < 0)
+ return -ENOMEM;
+
+ return sd_device_set_sysattr_value(device, sysattr, value);
+}
+
+_public_ int sd_device_trigger(sd_device *device, sd_device_action_t action) {
+ const char *s;
+
+ assert_return(device, -EINVAL);
+
+ s = device_action_to_string(action);
+ if (!s)
+ return -EINVAL;
+
+ /* This uses the simple no-UUID interface of kernel < 4.13 */
+ return sd_device_set_sysattr_value(device, "uevent", s);
+}
+
+_public_ int sd_device_trigger_with_uuid(
+ sd_device *device,
+ sd_device_action_t action,
+ sd_id128_t *ret_uuid) {
+
+ const char *s, *j;
+ sd_id128_t u;
+ int r;
+
+ assert_return(device, -EINVAL);
+
+ /* If no one wants to know the UUID, use the simple interface from pre-4.13 times */
+ if (!ret_uuid)
+ return sd_device_trigger(device, action);
+
+ s = device_action_to_string(action);
+ if (!s)
+ return -EINVAL;
+
+ r = sd_id128_randomize(&u);
+ if (r < 0)
+ return r;
+
+ j = strjoina(s, " ", SD_ID128_TO_UUID_STRING(u));
+
+ r = sd_device_set_sysattr_value(device, "uevent", j);
+ if (r < 0)
+ return r;
+
+ *ret_uuid = u;
+ return 0;
+}
+
+_public_ int sd_device_open(sd_device *device, int flags) {
+ _cleanup_close_ int fd = -1, fd2 = -1;
+ const char *devname, *subsystem = NULL;
+ uint64_t q, diskseq = 0;
+ struct stat st;
+ dev_t devnum;
+ int r;
+
+ assert_return(device, -EINVAL);
+ assert_return(FLAGS_SET(flags, O_PATH) || !FLAGS_SET(flags, O_NOFOLLOW), -EINVAL);
+
+ r = sd_device_get_devname(device, &devname);
+ if (r == -ENOENT)
+ return -ENOEXEC;
+ if (r < 0)
+ return r;
+
+ r = sd_device_get_devnum(device, &devnum);
+ if (r == -ENOENT)
+ return -ENOEXEC;
+ if (r < 0)
+ return r;
+
+ r = sd_device_get_subsystem(device, &subsystem);
+ if (r < 0 && r != -ENOENT)
+ return r;
+
+ fd = open(devname, FLAGS_SET(flags, O_PATH) ? flags : O_CLOEXEC|O_NOFOLLOW|O_PATH);
+ if (fd < 0)
+ return -errno;
+
+ if (fstat(fd, &st) < 0)
+ return -errno;
+
+ if (st.st_rdev != devnum)
+ return -ENXIO;
+
+ if (streq_ptr(subsystem, "block") ? !S_ISBLK(st.st_mode) : !S_ISCHR(st.st_mode))
+ return -ENXIO;
+
+ /* If flags has O_PATH, then we cannot check diskseq. Let's return earlier. */
+ if (FLAGS_SET(flags, O_PATH))
+ return TAKE_FD(fd);
+
+ /* If the device is not initialized, then we cannot determine if we should check diskseq through
+ * ID_IGNORE_DISKSEQ property. Let's skip to check diskseq in that case. */
+ r = sd_device_get_is_initialized(device);
+ if (r < 0)
+ return r;
+ if (r > 0) {
+ r = device_get_property_bool(device, "ID_IGNORE_DISKSEQ");
+ if (r < 0 && r != -ENOENT)
+ return r;
+ if (r <= 0) {
+ r = sd_device_get_diskseq(device, &diskseq);
+ if (r < 0 && r != -ENOENT)
+ return r;
+ }
+ }
+
+ fd2 = fd_reopen(fd, flags);
+ if (fd2 < 0)
+ return fd2;
+
+ if (diskseq == 0)
+ return TAKE_FD(fd2);
+
+ r = fd_get_diskseq(fd2, &q);
+ if (r < 0)
+ return r;
+
+ if (q != diskseq)
+ return -ENXIO;
+
+ return TAKE_FD(fd2);
+}
+
+int device_opendir(sd_device *device, const char *subdir, DIR **ret) {
+ _cleanup_closedir_ DIR *d = NULL;
+ _cleanup_free_ char *path = NULL;
+ const char *syspath;
+ int r;
+
+ assert(device);
+ assert(ret);
+
+ r = sd_device_get_syspath(device, &syspath);
+ if (r < 0)
+ return r;
+
+ if (subdir) {
+ if (!path_is_safe(subdir))
+ return -EINVAL;
+
+ path = path_join(syspath, subdir);
+ if (!path)
+ return -ENOMEM;
+ }
+
+ d = opendir(path ?: syspath);
+ if (!d)
+ return -errno;
+
+ *ret = TAKE_PTR(d);
+ return 0;
+}