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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 02:25:50 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 02:25:50 +0000
commit19f4f86bfed21c5326ed2acebe1163f3a83e832b (patch)
treed59b9989ce55ed23693e80974d94c856f1c2c8b1 /src/libsystemd/sd-device/device-enumerator.c
parentInitial commit. (diff)
downloadsystemd-19f4f86bfed21c5326ed2acebe1163f3a83e832b.tar.xz
systemd-19f4f86bfed21c5326ed2acebe1163f3a83e832b.zip
Adding upstream version 241.upstream/241upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/libsystemd/sd-device/device-enumerator.c')
-rw-r--r--src/libsystemd/sd-device/device-enumerator.c1004
1 files changed, 1004 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 0000000..20529aa
--- /dev/null
+++ b/src/libsystemd/sd-device/device-enumerator.c
@@ -0,0 +1,1004 @@
+/* SPDX-License-Identifier: LGPL-2.1+ */
+
+#include "sd-device.h"
+
+#include "alloc-util.h"
+#include "device-enumerator-private.h"
+#include "device-util.h"
+#include "dirent-util.h"
+#include "fd-util.h"
+#include "set.h"
+#include "string-util.h"
+#include "strv.h"
+#include "util.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;
+ sd_device **devices;
+ size_t n_devices, n_allocated, current_device_index;
+ 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_allow_uninitialized;
+};
+
+_public_ int sd_device_enumerator_new(sd_device_enumerator **ret) {
+ _cleanup_(sd_device_enumerator_unrefp) sd_device_enumerator *enumerator = NULL;
+
+ assert(ret);
+
+ enumerator = new(sd_device_enumerator, 1);
+ if (!enumerator)
+ return -ENOMEM;
+
+ *enumerator = (sd_device_enumerator) {
+ .n_ref = 1,
+ .type = _DEVICE_ENUMERATION_TYPE_INVALID,
+ };
+
+ *ret = TAKE_PTR(enumerator);
+
+ return 0;
+}
+
+static sd_device_enumerator *device_enumerator_free(sd_device_enumerator *enumerator) {
+ size_t i;
+
+ assert(enumerator);
+
+ for (i = 0; i < enumerator->n_devices; i++)
+ sd_device_unref(enumerator->devices[i]);
+
+ 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);
+
+ return mfree(enumerator);
+}
+
+DEFINE_PUBLIC_TRIVIAL_REF_UNREF_FUNC(sd_device_enumerator, sd_device_enumerator, device_enumerator_free);
+
+_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);
+
+ 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;
+
+ if (_value) {
+ 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);
+
+ r = hashmap_ensure_allocated(&enumerator->match_property, NULL);
+ if (r < 0)
+ return r;
+
+ property = strdup(_property);
+ if (!property)
+ return -ENOMEM;
+
+ if (_value) {
+ 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_allow_uninitialized(sd_device_enumerator *enumerator) {
+ assert_return(enumerator, -EINVAL);
+
+ enumerator->match_allow_uninitialized = true;
+
+ enumerator->scan_uptodate = false;
+
+ return 0;
+}
+
+int device_enumerator_add_match_is_initialized(sd_device_enumerator *enumerator) {
+ assert_return(enumerator, -EINVAL);
+
+ enumerator->match_allow_uninitialized = false;
+
+ enumerator->scan_uptodate = false;
+
+ return 0;
+}
+
+static int device_compare(sd_device * const *_a, sd_device * const *_b) {
+ sd_device *a = *(sd_device **)_a, *b = *(sd_device **)_b;
+ const char *devpath_a, *devpath_b, *sound_a;
+ bool delay_a, delay_b;
+ int r;
+
+ 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 */
+ delay_a = strstr(devpath_a, "/block/md") || strstr(devpath_a, "/block/dm-");
+ delay_b = strstr(devpath_b, "/block/md") || strstr(devpath_b, "/block/dm-");
+ r = CMP(delay_a, delay_b);
+ if (r != 0)
+ return r;
+
+ return strcmp(devpath_a, devpath_b);
+}
+
+int device_enumerator_add_device(sd_device_enumerator *enumerator, sd_device *device) {
+ assert_return(enumerator, -EINVAL);
+ assert_return(device, -EINVAL);
+
+ if (!GREEDY_REALLOC(enumerator->devices, enumerator->n_allocated, enumerator->n_devices + 1))
+ return -ENOMEM;
+
+ enumerator->devices[enumerator->n_devices++] = 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(value, sysattr, enumerator->nomatch_sysattr, i)
+ if (match_sysattr_value(device, sysattr, value))
+ return false;
+
+ HASHMAP_FOREACH_KEY(value, sysattr, 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(value, property, 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_(sd_device_unrefp) sd_device *device = NULL;
+ char syspath[strlen(path) + 1 + strlen(dent->d_name) + 1];
+ int 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) {
+ if (k != -ENODEV)
+ /* this is necessarily racey, so ignore missing devices */
+ r = k;
+
+ continue;
+ }
+
+ initialized = sd_device_get_is_initialized(device);
+ if (initialized < 0) {
+ r = initialized;
+ 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_allow_uninitialized &&
+ !initialized &&
+ (sd_device_get_devnum(device, NULL) >= 0 ||
+ sd_device_get_ifindex(device, NULL) >= 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 = 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("sd-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 log_debug_errno(errno, "sd-device-enumerator: Failed to open tags directory %s: %m", path);
+ return 0;
+ }
+
+ /* TODO: filter away subsystems? */
+
+ FOREACH_DIRENT_ALL(dent, dir, return -errno) {
+ _cleanup_(sd_device_unrefp) 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) {
+ if (k != -ENODEV)
+ /* this is necessarily racy, so ignore missing devices */
+ 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 = 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 = 0;
+
+ assert(enumerator);
+
+ SET_FOREACH(tag, enumerator->match_tag, i) {
+ int k;
+
+ k = enumerator_scan_devices_tag(enumerator, tag);
+ if (k < 0)
+ r = k;
+ }
+
+ return r;
+}
+
+static int parent_add_child(sd_device_enumerator *enumerator, const char *path) {
+ _cleanup_(sd_device_unrefp) sd_device *device = NULL;
+ const char *subsystem, *sysname;
+ int r;
+
+ r = sd_device_new_from_syspath(&device, path);
+ if (r == -ENODEV)
+ /* this is necessarily racy, so ignore missing devices */
+ return 0;
+ else if (r < 0)
+ return r;
+
+ r = sd_device_get_subsystem(device, &subsystem);
+ if (r == -ENOENT)
+ return 0;
+ 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 = 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)
+ return log_debug_errno(errno, "sd-device-enumerator: Failed to open parent directory %s: %m", path);
+
+ 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;
+
+ child = strjoin(path, "/", dent->d_name);
+ if (!child)
+ return -ENOMEM;
+
+ k = parent_add_child(enumerator, child);
+ if (k < 0)
+ r = k;
+
+ if (maxdepth > 0)
+ parent_crawl_children(enumerator, child, maxdepth - 1);
+ else
+ log_debug("sd-device-enumerator: 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("sd-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)
+ return log_debug_errno(r, "sd-device-enumerator: Failed to scan /sys/subsystem: %m");
+ } else {
+ int k;
+
+ k = enumerator_scan_dir(enumerator, "bus", "devices", NULL);
+ if (k < 0) {
+ log_debug_errno(k, "sd-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, "sd-device-enumerator: Failed to scan /sys/class: %m");
+ r = k;
+ }
+ }
+
+ return r;
+}
+
+static void device_enumerator_dedup_devices(sd_device_enumerator *enumerator) {
+ sd_device **a, **b, **end;
+
+ assert(enumerator);
+
+ if (enumerator->n_devices <= 1)
+ return;
+
+ a = enumerator->devices + 1;
+ b = enumerator->devices;
+ end = enumerator->devices + enumerator->n_devices;
+
+ for (; a < end; a++) {
+ const char *devpath_a, *devpath_b;
+
+ assert_se(sd_device_get_devpath(*a, &devpath_a) >= 0);
+ assert_se(sd_device_get_devpath(*b, &devpath_b) >= 0);
+
+ if (path_equal(devpath_a, devpath_b))
+ sd_device_unref(*a);
+ else
+ *(++b) = *a;
+ }
+
+ enumerator->n_devices = b - enumerator->devices + 1;
+}
+
+int device_enumerator_scan_devices(sd_device_enumerator *enumerator) {
+ int r = 0, k;
+ size_t i;
+
+ assert(enumerator);
+
+ if (enumerator->scan_uptodate &&
+ enumerator->type == DEVICE_ENUMERATION_TYPE_DEVICES)
+ return 0;
+
+ for (i = 0; i < enumerator->n_devices; i++)
+ sd_device_unref(enumerator->devices[i]);
+
+ enumerator->n_devices = 0;
+
+ if (!set_isempty(enumerator->match_tag)) {
+ k = enumerator_scan_devices_tags(enumerator);
+ if (k < 0)
+ r = k;
+ } else if (enumerator->match_parent) {
+ k = enumerator_scan_devices_children(enumerator);
+ if (k < 0)
+ r = k;
+ } else {
+ k = enumerator_scan_devices_all(enumerator);
+ if (k < 0)
+ r = k;
+ }
+
+ typesafe_qsort(enumerator->devices, enumerator->n_devices, device_compare);
+ device_enumerator_dedup_devices(enumerator);
+
+ enumerator->scan_uptodate = true;
+ enumerator->type = DEVICE_ENUMERATION_TYPE_DEVICES;
+
+ return r;
+}
+
+_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->current_device_index = 0;
+
+ if (enumerator->n_devices == 0)
+ return NULL;
+
+ return enumerator->devices[0];
+}
+
+_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 ||
+ enumerator->current_device_index + 1 >= enumerator->n_devices)
+ return NULL;
+
+ return enumerator->devices[++enumerator->current_device_index];
+}
+
+int device_enumerator_scan_subsystems(sd_device_enumerator *enumerator) {
+ const char *subsysdir;
+ int r = 0, k;
+ size_t i;
+
+ assert(enumerator);
+
+ if (enumerator->scan_uptodate &&
+ enumerator->type == DEVICE_ENUMERATION_TYPE_SUBSYSTEMS)
+ return 0;
+
+ for (i = 0; i < enumerator->n_devices; i++)
+ sd_device_unref(enumerator->devices[i]);
+
+ enumerator->n_devices = 0;
+
+ /* modules */
+ if (match_subsystem(enumerator, "module")) {
+ k = enumerator_scan_dir_and_add_devices(enumerator, "module", NULL, NULL);
+ if (k < 0) {
+ log_debug_errno(k, "sd-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, "sd-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, "sd-device-enumerator: Failed to scan drivers: %m");
+ r = k;
+ }
+ }
+
+ typesafe_qsort(enumerator->devices, enumerator->n_devices, device_compare);
+ device_enumerator_dedup_devices(enumerator);
+
+ enumerator->scan_uptodate = true;
+ enumerator->type = DEVICE_ENUMERATION_TYPE_SUBSYSTEMS;
+
+ 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->current_device_index = 0;
+
+ if (enumerator->n_devices == 0)
+ return NULL;
+
+ return enumerator->devices[0];
+}
+
+_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 ||
+ enumerator->current_device_index + 1 >= enumerator->n_devices)
+ return NULL;
+
+ return enumerator->devices[++enumerator->current_device_index];
+}
+
+sd_device *device_enumerator_get_first(sd_device_enumerator *enumerator) {
+ assert_return(enumerator, NULL);
+
+ if (!enumerator->scan_uptodate)
+ return NULL;
+
+ enumerator->current_device_index = 0;
+
+ if (enumerator->n_devices == 0)
+ return NULL;
+
+ return enumerator->devices[0];
+}
+
+sd_device *device_enumerator_get_next(sd_device_enumerator *enumerator) {
+ assert_return(enumerator, NULL);
+
+ if (!enumerator->scan_uptodate ||
+ enumerator->current_device_index + 1 >= enumerator->n_devices)
+ return NULL;
+
+ return enumerator->devices[++enumerator->current_device_index];
+}
+
+sd_device **device_enumerator_get_devices(sd_device_enumerator *enumerator, size_t *ret_n_devices) {
+ assert(enumerator);
+ assert(ret_n_devices);
+
+ if (!enumerator->scan_uptodate)
+ return NULL;
+
+ *ret_n_devices = enumerator->n_devices;
+ return enumerator->devices;
+}