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Diffstat (limited to 'src/libsystemd/sd-device/device-enumerator.c')
-rw-r--r--src/libsystemd/sd-device/device-enumerator.c972
1 files changed, 972 insertions, 0 deletions
diff --git a/src/libsystemd/sd-device/device-enumerator.c b/src/libsystemd/sd-device/device-enumerator.c
new file mode 100644
index 0000000000..37d46e57cf
--- /dev/null
+++ b/src/libsystemd/sd-device/device-enumerator.c
@@ -0,0 +1,972 @@
+/***
+ This file is part of systemd.
+
+ Copyright 2008-2012 Kay Sievers <kay@vrfy.org>
+ Copyright 2014-2015 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 "util.h"
+#include "prioq.h"
+#include "strv.h"
+#include "set.h"
+
+#include "sd-device.h"
+
+#include "device-util.h"
+#include "device-enumerator-private.h"
+
+#define DEVICE_ENUMERATE_MAX_DEPTH 256
+
+typedef enum DeviceEnumerationType {
+ DEVICE_ENUMERATION_TYPE_DEVICES,
+ DEVICE_ENUMERATION_TYPE_SUBSYSTEMS,
+ _DEVICE_ENUMERATION_TYPE_MAX,
+ _DEVICE_ENUMERATION_TYPE_INVALID = -1,
+} DeviceEnumerationType;
+
+struct sd_device_enumerator {
+ unsigned n_ref;
+
+ DeviceEnumerationType type;
+ Prioq *devices;
+ bool scan_uptodate;
+
+ Set *match_subsystem;
+ Set *nomatch_subsystem;
+ Hashmap *match_sysattr;
+ Hashmap *nomatch_sysattr;
+ Hashmap *match_property;
+ Set *match_sysname;
+ Set *match_tag;
+ sd_device *match_parent;
+ bool match_is_initialized;
+};
+
+_public_ int sd_device_enumerator_new(sd_device_enumerator **ret) {
+ _cleanup_device_enumerator_unref_ sd_device_enumerator *enumerator = NULL;
+
+ assert(ret);
+
+ enumerator = new0(sd_device_enumerator, 1);
+ if (!enumerator)
+ return -ENOMEM;
+
+ enumerator->n_ref = 1;
+ enumerator->type = _DEVICE_ENUMERATION_TYPE_INVALID;
+
+ *ret = enumerator;
+ enumerator = NULL;
+
+ return 0;
+}
+
+_public_ sd_device_enumerator *sd_device_enumerator_ref(sd_device_enumerator *enumerator) {
+ assert_return(enumerator, NULL);
+
+ assert_se((++ enumerator->n_ref) >= 2);
+
+ return enumerator;
+}
+
+_public_ sd_device_enumerator *sd_device_enumerator_unref(sd_device_enumerator *enumerator) {
+ if (enumerator && (-- enumerator->n_ref) == 0) {
+ sd_device *device;
+
+ while ((device = prioq_pop(enumerator->devices)))
+ sd_device_unref(device);
+
+ prioq_free(enumerator->devices);
+
+ set_free_free(enumerator->match_subsystem);
+ set_free_free(enumerator->nomatch_subsystem);
+ hashmap_free_free_free(enumerator->match_sysattr);
+ hashmap_free_free_free(enumerator->nomatch_sysattr);
+ hashmap_free_free_free(enumerator->match_property);
+ set_free_free(enumerator->match_sysname);
+ set_free_free(enumerator->match_tag);
+ sd_device_unref(enumerator->match_parent);
+
+ free(enumerator);
+ }
+
+ return NULL;
+}
+
+_public_ int sd_device_enumerator_add_match_subsystem(sd_device_enumerator *enumerator, const char *subsystem, int match) {
+ Set **set;
+ int r;
+
+ assert_return(enumerator, -EINVAL);
+ assert_return(subsystem, -EINVAL);
+
+ if (match)
+ set = &enumerator->match_subsystem;
+ else
+ set = &enumerator->nomatch_subsystem;
+
+ r = set_ensure_allocated(set, NULL);
+ if (r < 0)
+ return r;
+
+ r = set_put_strdup(*set, subsystem);
+ if (r < 0)
+ return r;
+
+ enumerator->scan_uptodate = false;
+
+ return 0;
+}
+
+_public_ int sd_device_enumerator_add_match_sysattr(sd_device_enumerator *enumerator, const char *_sysattr, const char *_value, int match) {
+ _cleanup_free_ char *sysattr = NULL, *value = NULL;
+ Hashmap **hashmap;
+ int r;
+
+ assert_return(enumerator, -EINVAL);
+ assert_return(_sysattr, -EINVAL);
+ assert_return(_value, -EINVAL);
+
+ if (match)
+ hashmap = &enumerator->match_sysattr;
+ else
+ hashmap = &enumerator->nomatch_sysattr;
+
+ r = hashmap_ensure_allocated(hashmap, NULL);
+ if (r < 0)
+ return r;
+
+ sysattr = strdup(_sysattr);
+ if (!sysattr)
+ return -ENOMEM;
+
+ value = strdup(_value);
+ if (!value)
+ return -ENOMEM;
+
+ r = hashmap_put(*hashmap, sysattr, value);
+ if (r < 0)
+ return r;
+
+ sysattr = NULL;
+ value = NULL;
+
+ enumerator->scan_uptodate = false;
+
+ return 0;
+}
+
+_public_ int sd_device_enumerator_add_match_property(sd_device_enumerator *enumerator, const char *_property, const char *_value) {
+ _cleanup_free_ char *property = NULL, *value = NULL;
+ int r;
+
+ assert_return(enumerator, -EINVAL);
+ assert_return(_property, -EINVAL);
+ assert_return(_value, -EINVAL);
+
+ r = hashmap_ensure_allocated(&enumerator->match_property, NULL);
+ if (r < 0)
+ return r;
+
+ property = strdup(_property);
+ if (!property)
+ return -ENOMEM;
+
+ value = strdup(_value);
+ if (!value)
+ return -ENOMEM;
+
+ r = hashmap_put(enumerator->match_property, property, value);
+ if (r < 0)
+ return r;
+
+ property = NULL;
+ value = NULL;
+
+ enumerator->scan_uptodate = false;
+
+ return 0;
+}
+
+_public_ int sd_device_enumerator_add_match_sysname(sd_device_enumerator *enumerator, const char *sysname) {
+ int r;
+
+ assert_return(enumerator, -EINVAL);
+ assert_return(sysname, -EINVAL);
+
+ r = set_ensure_allocated(&enumerator->match_sysname, NULL);
+ if (r < 0)
+ return r;
+
+ r = set_put_strdup(enumerator->match_sysname, sysname);
+ if (r < 0)
+ return r;
+
+ enumerator->scan_uptodate = false;
+
+ return 0;
+}
+
+_public_ int sd_device_enumerator_add_match_tag(sd_device_enumerator *enumerator, const char *tag) {
+ int r;
+
+ assert_return(enumerator, -EINVAL);
+ assert_return(tag, -EINVAL);
+
+ r = set_ensure_allocated(&enumerator->match_tag, NULL);
+ if (r < 0)
+ return r;
+
+ r = set_put_strdup(enumerator->match_tag, tag);
+ if (r < 0)
+ return r;
+
+ enumerator->scan_uptodate = false;
+
+ return 0;
+}
+
+_public_ int sd_device_enumerator_add_match_parent(sd_device_enumerator *enumerator, sd_device *parent) {
+ assert_return(enumerator, -EINVAL);
+ assert_return(parent, -EINVAL);
+
+ sd_device_unref(enumerator->match_parent);
+ enumerator->match_parent = sd_device_ref(parent);
+
+ enumerator->scan_uptodate = false;
+
+ return 0;
+}
+
+_public_ int sd_device_enumerator_add_match_is_initialized(sd_device_enumerator *enumerator) {
+ assert_return(enumerator, -EINVAL);
+
+ enumerator->match_is_initialized = true;
+
+ enumerator->scan_uptodate = false;
+
+ return 0;
+}
+
+static int device_compare(const void *_a, const void *_b) {
+ sd_device *a = (sd_device *)_a, *b = (sd_device *)_b;
+ const char *devpath_a, *devpath_b, *sound_a;
+ bool delay_a = false, delay_b = false;
+
+ assert_se(sd_device_get_devpath(a, &devpath_a) >= 0);
+ assert_se(sd_device_get_devpath(b, &devpath_b) >= 0);
+
+ sound_a = strstr(devpath_a, "/sound/card");
+ if (sound_a) {
+ /* For sound cards the control device must be enumerated last to
+ * make sure it's the final device node that gets ACLs applied.
+ * Applications rely on this fact and use ACL changes on the
+ * control node as an indicator that the ACL change of the
+ * entire sound card completed. The kernel makes this guarantee
+ * when creating those devices, and hence we should too when
+ * enumerating them. */
+ sound_a += strlen("/sound/card");
+ sound_a = strchr(sound_a, '/');
+
+ if (sound_a) {
+ unsigned prefix_len;
+
+ prefix_len = sound_a - devpath_a;
+
+ if (strncmp(devpath_a, devpath_b, prefix_len) == 0) {
+ const char *sound_b;
+
+ sound_b = devpath_b + prefix_len;
+
+ if (startswith(sound_a, "/controlC") &&
+ !startswith(sound_b, "/contolC"))
+ return 1;
+
+ if (!startswith(sound_a, "/controlC") &&
+ startswith(sound_b, "/controlC"))
+ return -1;
+ }
+ }
+ }
+
+ /* md and dm devices are enumerated after all other devices */
+ if (strstr(devpath_a, "/block/md") || strstr(devpath_a, "/block/dm-"))
+ delay_a = true;
+
+ if (strstr(devpath_b, "/block/md") || strstr(devpath_b, "/block/dm-"))
+ delay_b = true;
+
+ if (delay_a && !delay_b)
+ return 1;
+
+ if (!delay_a && delay_b)
+ return -1;
+
+ return strcmp(devpath_a, devpath_b);
+}
+
+_public_ int sd_device_enumerator_add_device(sd_device_enumerator *enumerator, sd_device *device) {
+ int r;
+
+ assert_return(enumerator, -EINVAL);
+ assert_return(device, -EINVAL);
+
+ r = prioq_ensure_allocated(&enumerator->devices, device_compare);
+ if (r < 0)
+ return r;
+
+ r = prioq_put(enumerator->devices, device, NULL);
+ if (r < 0)
+ return r;
+
+ sd_device_ref(device);
+
+ return 0;
+}
+
+static bool match_sysattr_value(sd_device *device, const char *sysattr, const char *match_value) {
+ const char *value;
+ int r;
+
+ assert(device);
+ assert(sysattr);
+
+ r = sd_device_get_sysattr_value(device, sysattr, &value);
+ if (r < 0)
+ return false;
+
+ if (!match_value)
+ return true;
+
+ if (fnmatch(match_value, value, 0) == 0)
+ return true;
+
+ return false;
+}
+
+static bool match_sysattr(sd_device_enumerator *enumerator, sd_device *device) {
+ const char *sysattr;
+ const char *value;
+ Iterator i;
+
+ assert(enumerator);
+ assert(device);
+
+ HASHMAP_FOREACH_KEY(sysattr, value, enumerator->nomatch_sysattr, i)
+ if (match_sysattr_value(device, sysattr, value))
+ return false;
+
+ HASHMAP_FOREACH_KEY(sysattr, value, enumerator->match_sysattr, i)
+ if (!match_sysattr_value(device, sysattr, value))
+ return false;
+
+ return true;
+}
+
+static bool match_property(sd_device_enumerator *enumerator, sd_device *device) {
+ const char *property;
+ const char *value;
+ Iterator i;
+
+ assert(enumerator);
+ assert(device);
+
+ if (hashmap_isempty(enumerator->match_property))
+ return true;
+
+ HASHMAP_FOREACH_KEY(property, value, enumerator->match_property, i) {
+ const char *property_dev, *value_dev;
+
+ FOREACH_DEVICE_PROPERTY(device, property_dev, value_dev) {
+ if (fnmatch(property, property_dev, 0) != 0)
+ continue;
+
+ if (!value && !value_dev)
+ return true;
+
+ if (!value || !value_dev)
+ continue;
+
+ if (fnmatch(value, value_dev, 0) == 0)
+ return true;
+ }
+ }
+
+ return false;
+}
+
+static bool match_tag(sd_device_enumerator *enumerator, sd_device *device) {
+ const char *tag;
+ Iterator i;
+
+ assert(enumerator);
+ assert(device);
+
+ SET_FOREACH(tag, enumerator->match_tag, i)
+ if (!sd_device_has_tag(device, tag))
+ return false;
+
+ return true;
+}
+
+static bool match_parent(sd_device_enumerator *enumerator, sd_device *device) {
+ const char *devpath, *devpath_dev;
+ int r;
+
+ assert(enumerator);
+ assert(device);
+
+ if (!enumerator->match_parent)
+ return true;
+
+ r = sd_device_get_devpath(enumerator->match_parent, &devpath);
+ assert(r >= 0);
+
+ r = sd_device_get_devpath(device, &devpath_dev);
+ assert(r >= 0);
+
+ return startswith(devpath_dev, devpath);
+}
+
+static bool match_sysname(sd_device_enumerator *enumerator, const char *sysname) {
+ const char *sysname_match;
+ Iterator i;
+
+ assert(enumerator);
+ assert(sysname);
+
+ if (set_isempty(enumerator->match_sysname))
+ return true;
+
+ SET_FOREACH(sysname_match, enumerator->match_sysname, i)
+ if (fnmatch(sysname_match, sysname, 0) == 0)
+ return true;
+
+ return false;
+}
+
+static int enumerator_scan_dir_and_add_devices(sd_device_enumerator *enumerator, const char *basedir, const char *subdir1, const char *subdir2) {
+ _cleanup_closedir_ DIR *dir = NULL;
+ char *path;
+ struct dirent *dent;
+ int r = 0;
+
+ assert(enumerator);
+ assert(basedir);
+
+ path = strjoina("/sys/", basedir, "/");
+
+ if (subdir1)
+ path = strjoina(path, subdir1, "/");
+
+ if (subdir2)
+ path = strjoina(path, subdir2, "/");
+
+ dir = opendir(path);
+ if (!dir)
+ return -errno;
+
+ FOREACH_DIRENT_ALL(dent, dir, return -errno) {
+ _cleanup_device_unref_ sd_device *device = NULL;
+ char syspath[strlen(path) + 1 + strlen(dent->d_name) + 1];
+ dev_t devnum;
+ int ifindex, initialized, k;
+
+ if (dent->d_name[0] == '.')
+ continue;
+
+ if (!match_sysname(enumerator, dent->d_name))
+ continue;
+
+ (void)sprintf(syspath, "%s%s", path, dent->d_name);
+
+ k = sd_device_new_from_syspath(&device, syspath);
+ if (k < 0) {
+ log_debug_errno(k, "device-enumerator: failed to create device from syspath %s: %m", syspath);
+ r = k;
+ continue;
+ }
+
+ k = sd_device_get_devnum(device, &devnum);
+ if (k < 0) {
+ r = k;
+ continue;
+ }
+
+ k = sd_device_get_ifindex(device, &ifindex);
+ if (k < 0) {
+ r = k;
+ continue;
+ }
+
+ k = sd_device_get_is_initialized(device, &initialized);
+ if (k < 0) {
+ r = k;
+ continue;
+ }
+
+ /*
+ * All devices with a device node or network interfaces
+ * possibly need udev to adjust the device node permission
+ * or context, or rename the interface before it can be
+ * reliably used from other processes.
+ *
+ * For now, we can only check these types of devices, we
+ * might not store a database, and have no way to find out
+ * for all other types of devices.
+ */
+ if (enumerator->match_is_initialized &&
+ !initialized &&
+ (major(devnum) > 0 || ifindex > 0))
+ continue;
+
+ if (!match_parent(enumerator, device))
+ continue;
+
+ if (!match_tag(enumerator, device))
+ continue;
+
+ if (!match_property(enumerator, device))
+ continue;
+
+ if (!match_sysattr(enumerator, device))
+ continue;
+
+ k = sd_device_enumerator_add_device(enumerator, device);
+ if (k < 0)
+ r = k;
+ }
+
+ return r;
+}
+
+static bool match_subsystem(sd_device_enumerator *enumerator, const char *subsystem) {
+ const char *subsystem_match;
+ Iterator i;
+
+ assert(enumerator);
+
+ if (!subsystem)
+ return false;
+
+ SET_FOREACH(subsystem_match, enumerator->nomatch_subsystem, i)
+ if (fnmatch(subsystem_match, subsystem, 0) == 0)
+ return false;
+
+ if (set_isempty(enumerator->match_subsystem))
+ return true;
+
+ SET_FOREACH(subsystem_match, enumerator->match_subsystem, i)
+ if (fnmatch(subsystem_match, subsystem, 0) == 0)
+ return true;
+
+ return false;
+}
+
+static int enumerator_scan_dir(sd_device_enumerator *enumerator, const char *basedir, const char *subdir, const char *subsystem) {
+ _cleanup_closedir_ DIR *dir = NULL;
+ char *path;
+ struct dirent *dent;
+ int r = 0;
+
+ path = strjoina("/sys/", basedir);
+
+ dir = opendir(path);
+ if (!dir)
+ return -errno;
+
+ log_debug(" device-enumerator: scanning %s", path);
+
+ FOREACH_DIRENT_ALL(dent, dir, return -errno) {
+ int k;
+
+ if (dent->d_name[0] == '.')
+ continue;
+
+ if (!match_subsystem(enumerator, subsystem ? : dent->d_name))
+ continue;
+
+ k = enumerator_scan_dir_and_add_devices(enumerator, basedir, dent->d_name, subdir);
+ if (k < 0)
+ r = k;
+ }
+
+ return r;
+}
+
+static int enumerator_scan_devices_tag(sd_device_enumerator *enumerator, const char *tag) {
+ _cleanup_closedir_ DIR *dir = NULL;
+ char *path;
+ struct dirent *dent;
+ int r = 0;
+
+ assert(enumerator);
+ assert(tag);
+
+ path = strjoina("/run/udev/tags/", tag);
+
+ dir = opendir(path);
+ if (!dir) {
+ if (errno == ENOENT)
+ return 0;
+ else {
+ log_error("sd-device-enumerator: could not open tags directory %s: %m", path);
+ return -errno;
+ }
+ }
+
+ /* TODO: filter away subsystems? */
+
+ FOREACH_DIRENT_ALL(dent, dir, return -errno) {
+ _cleanup_device_unref_ sd_device *device = NULL;
+ const char *subsystem, *sysname;
+ int k;
+
+ if (dent->d_name[0] == '.')
+ continue;
+
+ k = sd_device_new_from_device_id(&device, dent->d_name);
+ if (k < 0) {
+ r = k;
+ continue;
+ }
+
+ k = sd_device_get_subsystem(device, &subsystem);
+ if (k < 0) {
+ r = k;
+ continue;
+ }
+
+ if (!match_subsystem(enumerator, subsystem))
+ continue;
+
+ k = sd_device_get_sysname(device, &sysname);
+ if (k < 0) {
+ r = k;
+ continue;
+ }
+
+ if (!match_sysname(enumerator, sysname))
+ continue;
+
+ if (!match_parent(enumerator, device))
+ continue;
+
+ if (!match_property(enumerator, device))
+ continue;
+
+ if (!match_sysattr(enumerator, device))
+ continue;
+
+ k = sd_device_enumerator_add_device(enumerator, device);
+ if (k < 0) {
+ r = k;
+ continue;
+ }
+ }
+
+ return r;
+}
+
+static int enumerator_scan_devices_tags(sd_device_enumerator *enumerator) {
+ const char *tag;
+ Iterator i;
+ int r;
+
+ assert(enumerator);
+
+ SET_FOREACH(tag, enumerator->match_tag, i) {
+ r = enumerator_scan_devices_tag(enumerator, tag);
+ if (r < 0)
+ return r;
+ }
+
+ return 0;
+}
+
+static int parent_add_child(sd_device_enumerator *enumerator, const char *path) {
+ _cleanup_device_unref_ sd_device *device = NULL;
+ const char *subsystem, *sysname;
+ int r;
+
+ r = sd_device_new_from_syspath(&device, path);
+ if (r == -ENOENT)
+ return 0;
+ else if (r < 0)
+ return r;
+
+ r = sd_device_get_subsystem(device, &subsystem);
+ if (r < 0)
+ return r;
+
+ if (!match_subsystem(enumerator, subsystem))
+ return 0;
+
+ r = sd_device_get_sysname(device, &sysname);
+ if (r < 0)
+ return r;
+
+ if (!match_sysname(enumerator, sysname))
+ return 0;
+
+ if (!match_property(enumerator, device))
+ return 0;
+
+ if (!match_sysattr(enumerator, device))
+ return 0;
+
+ r = sd_device_enumerator_add_device(enumerator, device);
+ if (r < 0)
+ return r;
+
+ return 1;
+}
+
+static int parent_crawl_children(sd_device_enumerator *enumerator, const char *path, unsigned maxdepth) {
+ _cleanup_closedir_ DIR *dir = NULL;
+ struct dirent *dent;
+ int r = 0;
+
+ dir = opendir(path);
+ if (!dir) {
+ log_debug("sd-device-enumerate: could not open parent directory %s: %m", path);
+ return -errno;
+ }
+
+ FOREACH_DIRENT_ALL(dent, dir, return -errno) {
+ _cleanup_free_ char *child = NULL;
+ int k;
+
+ if (dent->d_name[0] == '.')
+ continue;
+
+ if (dent->d_type != DT_DIR)
+ continue;
+
+ k = asprintf(&child, "%s/%s", path, dent->d_name);
+ if (k < 0)
+ return -errno;
+
+ k = parent_add_child(enumerator, child);
+ if (k < 0)
+ r = k;
+
+ if (maxdepth > 0)
+ parent_crawl_children(enumerator, child, maxdepth - 1);
+ else
+ log_debug("device-enumerate: max depth reached, %s: ignoring devices", child);
+ }
+
+ return r;
+}
+
+static int enumerator_scan_devices_children(sd_device_enumerator *enumerator) {
+ const char *path;
+ int r = 0, k;
+
+ r = sd_device_get_syspath(enumerator->match_parent, &path);
+ if (r < 0)
+ return r;
+
+ k = parent_add_child(enumerator, path);
+ if (k < 0)
+ r = k;
+
+ k = parent_crawl_children(enumerator, path, DEVICE_ENUMERATE_MAX_DEPTH);
+ if (k < 0)
+ r = k;
+
+ return r;
+}
+
+static int enumerator_scan_devices_all(sd_device_enumerator *enumerator) {
+ int r = 0;
+
+ log_debug("device-enumerator: scan all dirs");
+
+ if (access("/sys/subsystem", F_OK) >= 0) {
+ /* we have /subsystem/, forget all the old stuff */
+ r = enumerator_scan_dir(enumerator, "subsystem", "devices", NULL);
+ if (r < 0) {
+ log_debug("device-enumerator: failed to scan /sys/subsystem: %s", strerror(-r));
+ return r;
+ }
+ } else {
+ int k;
+
+ k = enumerator_scan_dir(enumerator, "bus", "devices", NULL);
+ if (k < 0) {
+ log_debug_errno(k, "device-enumerator: failed to scan /sys/bus: %m");
+ r = k;
+ }
+
+ k = enumerator_scan_dir(enumerator, "class", NULL, NULL);
+ if (k < 0) {
+ log_debug_errno(k, "device-enumerator: failed to scan /sys/class: %m");
+ r = k;
+ }
+ }
+
+ return r;
+}
+
+int device_enumerator_scan_devices(sd_device_enumerator *enumerator) {
+ sd_device *device;
+ int r;
+
+ assert(enumerator);
+
+ if (enumerator->scan_uptodate &&
+ enumerator->type == DEVICE_ENUMERATION_TYPE_DEVICES)
+ return 0;
+
+ while ((device = prioq_pop(enumerator->devices)))
+ sd_device_unref(device);
+
+ if (!set_isempty(enumerator->match_tag)) {
+ r = enumerator_scan_devices_tags(enumerator);
+ if (r < 0)
+ return r;
+ } else if (enumerator->match_parent) {
+ r = enumerator_scan_devices_children(enumerator);
+ if (r < 0)
+ return r;
+ } else {
+ r = enumerator_scan_devices_all(enumerator);
+ if (r < 0)
+ return r;
+ }
+
+ enumerator->scan_uptodate = true;
+
+ return 0;
+}
+
+_public_ sd_device *sd_device_enumerator_get_device_first(sd_device_enumerator *enumerator) {
+ int r;
+
+ assert_return(enumerator, NULL);
+
+ r = device_enumerator_scan_devices(enumerator);
+ if (r < 0)
+ return NULL;
+
+ enumerator->type = DEVICE_ENUMERATION_TYPE_DEVICES;
+
+ return prioq_peek(enumerator->devices);
+}
+
+_public_ sd_device *sd_device_enumerator_get_device_next(sd_device_enumerator *enumerator) {
+ assert_return(enumerator, NULL);
+
+ if (!enumerator->scan_uptodate ||
+ enumerator->type != DEVICE_ENUMERATION_TYPE_DEVICES)
+ return NULL;
+
+ sd_device_unref(prioq_pop(enumerator->devices));
+
+ return prioq_peek(enumerator->devices);
+}
+
+int device_enumerator_scan_subsystems(sd_device_enumerator *enumerator) {
+ sd_device *device;
+ const char *subsysdir;
+ int r = 0, k;
+
+ assert(enumerator);
+
+ if (enumerator->scan_uptodate &&
+ enumerator->type == DEVICE_ENUMERATION_TYPE_SUBSYSTEMS)
+ return 0;
+
+ while ((device = prioq_pop(enumerator->devices)))
+ sd_device_unref(device);
+
+ /* modules */
+ if (match_subsystem(enumerator, "module")) {
+ k = enumerator_scan_dir_and_add_devices(enumerator, "module", NULL, NULL);
+ if (k < 0) {
+ log_debug_errno(k, "device-enumerator: failed to scan modules: %m");
+ r = k;
+ }
+ }
+
+ if (access("/sys/subsystem", F_OK) >= 0)
+ subsysdir = "subsystem";
+ else
+ subsysdir = "bus";
+
+ /* subsystems (only buses support coldplug) */
+ if (match_subsystem(enumerator, "subsystem")) {
+ k = enumerator_scan_dir_and_add_devices(enumerator, subsysdir, NULL, NULL);
+ if (k < 0) {
+ log_debug_errno(k, "device-enumerator: failed to scan subsystems: %m");
+ r = k;
+ }
+ }
+
+ /* subsystem drivers */
+ if (match_subsystem(enumerator, "drivers")) {
+ k = enumerator_scan_dir(enumerator, subsysdir, "drivers", "drivers");
+ if (k < 0) {
+ log_debug_errno(k, "device-enumerator: failed to scan drivers: %m");
+ r = k;
+ }
+ }
+
+ enumerator->scan_uptodate = true;
+
+ return r;
+}
+
+_public_ sd_device *sd_device_enumerator_get_subsystem_first(sd_device_enumerator *enumerator) {
+ int r;
+
+ assert_return(enumerator, NULL);
+
+ r = device_enumerator_scan_subsystems(enumerator);
+ if (r < 0)
+ return NULL;
+
+ enumerator->type = DEVICE_ENUMERATION_TYPE_SUBSYSTEMS;
+
+ return prioq_peek(enumerator->devices);
+}
+
+_public_ sd_device *sd_device_enumerator_get_subsystem_next(sd_device_enumerator *enumerator) {
+ assert_return(enumerator, NULL);
+
+ if (enumerator->scan_uptodate ||
+ enumerator->type != DEVICE_ENUMERATION_TYPE_SUBSYSTEMS)
+ return NULL;
+
+ sd_device_unref(prioq_pop(enumerator->devices));
+
+ return prioq_peek(enumerator->devices);
+}
+
+sd_device *device_enumerator_get_first(sd_device_enumerator *enumerator) {
+ assert_return(enumerator, NULL);
+
+ return prioq_peek(enumerator->devices);
+}
+
+sd_device *device_enumerator_get_next(sd_device_enumerator *enumerator) {
+ assert_return(enumerator, NULL);
+
+ sd_device_unref(prioq_pop(enumerator->devices));
+
+ return prioq_peek(enumerator->devices);
+}