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-rw-r--r--src/libsystemd/sd-device/device-enumerator.c1175
1 files changed, 1175 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..c215b92
--- /dev/null
+++ b/src/libsystemd/sd-device/device-enumerator.c
@@ -0,0 +1,1175 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+
+#include <fcntl.h>
+#include <unistd.h>
+
+#include "sd-device.h"
+
+#include "alloc-util.h"
+#include "device-enumerator-private.h"
+#include "device-filter.h"
+#include "device-util.h"
+#include "dirent-util.h"
+#include "fd-util.h"
+#include "set.h"
+#include "sort-util.h"
+#include "string-util.h"
+#include "strv.h"
+
+typedef enum DeviceEnumerationType {
+ DEVICE_ENUMERATION_TYPE_DEVICES,
+ DEVICE_ENUMERATION_TYPE_SUBSYSTEMS,
+ DEVICE_ENUMERATION_TYPE_ALL,
+ _DEVICE_ENUMERATION_TYPE_MAX,
+ _DEVICE_ENUMERATION_TYPE_INVALID = -EINVAL,
+} DeviceEnumerationType;
+
+struct sd_device_enumerator {
+ unsigned n_ref;
+
+ DeviceEnumerationType type;
+ Hashmap *devices_by_syspath;
+ sd_device **devices;
+ size_t n_devices, current_device_index;
+ bool scan_uptodate;
+ bool sorted;
+
+ char **prioritized_subsystems;
+ Set *match_subsystem;
+ Set *nomatch_subsystem;
+ Hashmap *match_sysattr;
+ Hashmap *nomatch_sysattr;
+ Hashmap *match_property;
+ Set *match_sysname;
+ Set *nomatch_sysname;
+ Set *match_tag;
+ Set *match_parent;
+ MatchInitializedType match_initialized;
+};
+
+_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,
+ .match_initialized = MATCH_INITIALIZED_COMPAT,
+ };
+
+ *ret = TAKE_PTR(enumerator);
+
+ return 0;
+}
+
+static void device_unref_many(sd_device **devices, size_t n) {
+ assert(devices || n == 0);
+
+ for (size_t i = 0; i < n; i++)
+ sd_device_unref(devices[i]);
+}
+
+static void device_enumerator_unref_devices(sd_device_enumerator *enumerator) {
+ assert(enumerator);
+
+ hashmap_clear_with_destructor(enumerator->devices_by_syspath, sd_device_unref);
+ device_unref_many(enumerator->devices, enumerator->n_devices);
+ enumerator->devices = mfree(enumerator->devices);
+ enumerator->n_devices = 0;
+}
+
+static sd_device_enumerator *device_enumerator_free(sd_device_enumerator *enumerator) {
+ assert(enumerator);
+
+ device_enumerator_unref_devices(enumerator);
+
+ hashmap_free(enumerator->devices_by_syspath);
+ strv_free(enumerator->prioritized_subsystems);
+ set_free(enumerator->match_subsystem);
+ set_free(enumerator->nomatch_subsystem);
+ hashmap_free(enumerator->match_sysattr);
+ hashmap_free(enumerator->nomatch_sysattr);
+ hashmap_free(enumerator->match_property);
+ set_free(enumerator->match_sysname);
+ set_free(enumerator->nomatch_sysname);
+ set_free(enumerator->match_tag);
+ set_free(enumerator->match_parent);
+
+ return mfree(enumerator);
+}
+
+DEFINE_PUBLIC_TRIVIAL_REF_UNREF_FUNC(sd_device_enumerator, sd_device_enumerator, device_enumerator_free);
+
+int device_enumerator_add_prioritized_subsystem(sd_device_enumerator *enumerator, const char *subsystem) {
+ int r;
+
+ assert(enumerator);
+ assert(subsystem);
+
+ if (strv_contains(enumerator->prioritized_subsystems, subsystem))
+ return 0;
+
+ r = strv_extend(&enumerator->prioritized_subsystems, subsystem);
+ if (r < 0)
+ return r;
+
+ enumerator->scan_uptodate = false;
+
+ return 1;
+}
+
+_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_put_strdup(set, subsystem);
+ if (r <= 0)
+ return r;
+
+ enumerator->scan_uptodate = false;
+
+ return 1;
+}
+
+_public_ int sd_device_enumerator_add_match_sysattr(sd_device_enumerator *enumerator, const char *sysattr, const char *value, int match) {
+ Hashmap **hashmap;
+ int r;
+
+ assert_return(enumerator, -EINVAL);
+ assert_return(sysattr, -EINVAL);
+
+ if (match)
+ hashmap = &enumerator->match_sysattr;
+ else
+ hashmap = &enumerator->nomatch_sysattr;
+
+ r = update_match_strv(hashmap, sysattr, value, /* clear_on_null = */ true);
+ if (r <= 0)
+ return r;
+
+ enumerator->scan_uptodate = false;
+
+ return 1;
+}
+
+_public_ int sd_device_enumerator_add_match_property(sd_device_enumerator *enumerator, const char *property, const char *value) {
+ int r;
+
+ assert_return(enumerator, -EINVAL);
+ assert_return(property, -EINVAL);
+
+ r = update_match_strv(&enumerator->match_property, property, value, /* clear_on_null = */ false);
+ if (r <= 0)
+ return r;
+
+ enumerator->scan_uptodate = false;
+
+ return 1;
+}
+
+static int device_enumerator_add_match_sysname(sd_device_enumerator *enumerator, const char *sysname, bool match) {
+ int r;
+
+ assert_return(enumerator, -EINVAL);
+ assert_return(sysname, -EINVAL);
+
+ r = set_put_strdup(match ? &enumerator->match_sysname : &enumerator->nomatch_sysname, sysname);
+ if (r <= 0)
+ return r;
+
+ enumerator->scan_uptodate = false;
+
+ return 1;
+}
+
+_public_ int sd_device_enumerator_add_match_sysname(sd_device_enumerator *enumerator, const char *sysname) {
+ return device_enumerator_add_match_sysname(enumerator, sysname, true);
+}
+
+_public_ int sd_device_enumerator_add_nomatch_sysname(sd_device_enumerator *enumerator, const char *sysname) {
+ return device_enumerator_add_match_sysname(enumerator, sysname, false);
+}
+
+_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_put_strdup(&enumerator->match_tag, tag);
+ if (r <= 0)
+ return r;
+
+ enumerator->scan_uptodate = false;
+
+ return 1;
+}
+
+int device_enumerator_add_match_parent_incremental(sd_device_enumerator *enumerator, sd_device *parent) {
+ const char *path;
+ int r;
+
+ assert(enumerator);
+ assert(parent);
+
+ r = sd_device_get_syspath(parent, &path);
+ if (r < 0)
+ return r;
+
+ r = set_put_strdup(&enumerator->match_parent, path);
+ if (r <= 0)
+ return r;
+
+ enumerator->scan_uptodate = false;
+
+ return 1;
+}
+
+_public_ int sd_device_enumerator_add_match_parent(sd_device_enumerator *enumerator, sd_device *parent) {
+ assert_return(enumerator, -EINVAL);
+ assert_return(parent, -EINVAL);
+
+ set_clear(enumerator->match_parent);
+
+ return device_enumerator_add_match_parent_incremental(enumerator, parent);
+}
+
+_public_ int sd_device_enumerator_allow_uninitialized(sd_device_enumerator *enumerator) {
+ assert_return(enumerator, -EINVAL);
+
+ enumerator->match_initialized = MATCH_INITIALIZED_ALL;
+
+ enumerator->scan_uptodate = false;
+
+ return 1;
+}
+
+int device_enumerator_add_match_is_initialized(sd_device_enumerator *enumerator, MatchInitializedType type) {
+ assert_return(enumerator, -EINVAL);
+ assert_return(type >= 0 && type < _MATCH_INITIALIZED_MAX, -EINVAL);
+
+ enumerator->match_initialized = type;
+
+ enumerator->scan_uptodate = false;
+
+ return 1;
+}
+
+static int sound_device_compare(const char *devpath_a, const char *devpath_b) {
+ const char *sound_a, *sound_b;
+ size_t prefix_len;
+
+ assert(devpath_a);
+ assert(devpath_b);
+
+ /* 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 = strstrafter(devpath_a, "/sound/card");
+ if (!sound_a)
+ return 0;
+
+ sound_a = strchr(devpath_a, '/');
+ if (!sound_a)
+ return 0;
+
+ prefix_len = sound_a - devpath_a;
+
+ if (!strneq(devpath_a, devpath_b, prefix_len))
+ return 0;
+
+ sound_b = devpath_b + prefix_len;
+
+ return CMP(!!startswith(sound_a, "/controlC"),
+ !!startswith(sound_b, "/controlC"));
+}
+
+static bool devpath_is_late_block(const char *devpath) {
+ assert(devpath);
+
+ return strstr(devpath, "/block/md") || strstr(devpath, "/block/dm-");
+}
+
+static int device_compare(sd_device * const *a, sd_device * const *b) {
+ const char *devpath_a, *devpath_b;
+ int r;
+
+ assert(a);
+ assert(b);
+ assert(*a);
+ assert(*b);
+
+ assert_se(sd_device_get_devpath(*(sd_device**) a, &devpath_a) >= 0);
+ assert_se(sd_device_get_devpath(*(sd_device**) b, &devpath_b) >= 0);
+
+ r = sound_device_compare(devpath_a, devpath_b);
+ if (r != 0)
+ return r;
+
+ /* md and dm devices are enumerated after all other devices */
+ r = CMP(devpath_is_late_block(devpath_a), devpath_is_late_block(devpath_b));
+ if (r != 0)
+ return r;
+
+ return path_compare(devpath_a, devpath_b);
+}
+
+static int enumerator_sort_devices(sd_device_enumerator *enumerator) {
+ size_t n_sorted = 0, n = 0;
+ sd_device **devices;
+ sd_device *device;
+ int r;
+
+ assert(enumerator);
+
+ if (enumerator->sorted)
+ return 0;
+
+ devices = new(sd_device*, hashmap_size(enumerator->devices_by_syspath));
+ if (!devices)
+ return -ENOMEM;
+
+ STRV_FOREACH(prioritized_subsystem, enumerator->prioritized_subsystems) {
+
+ for (;;) {
+ const char *syspath;
+ size_t m = n;
+
+ HASHMAP_FOREACH_KEY(device, syspath, enumerator->devices_by_syspath) {
+ _cleanup_free_ char *p = NULL;
+ const char *subsys;
+
+ if (sd_device_get_subsystem(device, &subsys) < 0)
+ continue;
+
+ if (!streq(subsys, *prioritized_subsystem))
+ continue;
+
+ devices[n++] = sd_device_ref(device);
+
+ for (;;) {
+ _cleanup_free_ char *q = NULL;
+
+ r = path_extract_directory(p ?: syspath, &q);
+ if (r == -EADDRNOTAVAIL)
+ break;
+ if (r < 0)
+ goto failed;
+
+ device = hashmap_get(enumerator->devices_by_syspath, q);
+ if (device)
+ devices[n++] = sd_device_ref(device);
+
+ free_and_replace(p, q);
+ }
+
+ break;
+ }
+
+ /* We cannot remove multiple entries in the loop HASHMAP_FOREACH_KEY() above. */
+ for (size_t i = m; i < n; i++) {
+ r = sd_device_get_syspath(devices[i], &syspath);
+ if (r < 0)
+ goto failed;
+
+ assert_se(hashmap_remove(enumerator->devices_by_syspath, syspath) == devices[i]);
+ sd_device_unref(devices[i]);
+ }
+
+ if (m == n)
+ break;
+ }
+
+ typesafe_qsort(devices + n_sorted, n - n_sorted, device_compare);
+ n_sorted = n;
+ }
+
+ HASHMAP_FOREACH(device, enumerator->devices_by_syspath)
+ devices[n++] = sd_device_ref(device);
+
+ /* Move all devices back to the hashmap. Otherwise, devices added by
+ * udev_enumerate_add_syspath() -> device_enumerator_add_device() may not be listed. */
+ for (size_t i = 0; i < n_sorted; i++) {
+ const char *syspath;
+
+ r = sd_device_get_syspath(devices[i], &syspath);
+ if (r < 0)
+ goto failed;
+
+ r = hashmap_put(enumerator->devices_by_syspath, syspath, devices[i]);
+ if (r < 0)
+ goto failed;
+ assert(r > 0);
+
+ sd_device_ref(devices[i]);
+ }
+
+ typesafe_qsort(devices + n_sorted, n - n_sorted, device_compare);
+
+ device_unref_many(enumerator->devices, enumerator->n_devices);
+
+ enumerator->n_devices = n;
+ free_and_replace(enumerator->devices, devices);
+
+ enumerator->sorted = true;
+ return 0;
+
+failed:
+ device_unref_many(devices, n);
+ free(devices);
+ return r;
+}
+
+int device_enumerator_add_device(sd_device_enumerator *enumerator, sd_device *device) {
+ const char *syspath;
+ int r;
+
+ assert_return(enumerator, -EINVAL);
+ assert_return(device, -EINVAL);
+
+ r = sd_device_get_syspath(device, &syspath);
+ if (r < 0)
+ return r;
+
+ r = hashmap_ensure_put(&enumerator->devices_by_syspath, &string_hash_ops, syspath, device);
+ if (IN_SET(r, -EEXIST, 0))
+ return 0;
+ if (r < 0)
+ return r;
+
+ sd_device_ref(device);
+
+ enumerator->sorted = false;
+ return 1;
+}
+
+static bool match_property(sd_device_enumerator *enumerator, sd_device *device) {
+ const char *property_pattern;
+ char * const *value_patterns;
+
+ assert(enumerator);
+ assert(device);
+
+ /* Unlike device_match_sysattr(), this accepts device that has at least one matching property. */
+
+ if (hashmap_isempty(enumerator->match_property))
+ return true;
+
+ HASHMAP_FOREACH_KEY(value_patterns, property_pattern, enumerator->match_property) {
+ const char *property, *value;
+
+ FOREACH_DEVICE_PROPERTY(device, property, value) {
+ if (fnmatch(property_pattern, property, 0) != 0)
+ continue;
+
+ if (strv_fnmatch(value_patterns, value))
+ return true;
+ }
+ }
+
+ return false;
+}
+
+static bool match_tag(sd_device_enumerator *enumerator, sd_device *device) {
+ const char *tag;
+
+ assert(enumerator);
+ assert(device);
+
+ SET_FOREACH(tag, enumerator->match_tag)
+ if (!sd_device_has_tag(device, tag))
+ return false;
+
+ return true;
+}
+
+static bool match_sysname(sd_device_enumerator *enumerator, const char *sysname) {
+ assert(enumerator);
+ assert(sysname);
+
+ return set_fnmatch(enumerator->match_sysname, enumerator->nomatch_sysname, sysname);
+}
+
+static int match_initialized(sd_device_enumerator *enumerator, sd_device *device) {
+ int r;
+
+ assert(enumerator);
+ assert(device);
+
+ if (enumerator->match_initialized == MATCH_INITIALIZED_ALL)
+ return true;
+
+ r = sd_device_get_is_initialized(device);
+ if (r == -ENOENT) /* this is necessarily racey, so ignore missing devices */
+ return false;
+ if (r < 0)
+ return r;
+
+ if (enumerator->match_initialized == MATCH_INITIALIZED_COMPAT) {
+ /* only devices that have no devnode/ifindex or have a db entry are accepted. */
+ if (r > 0)
+ return true;
+
+ if (sd_device_get_devnum(device, NULL) >= 0)
+ return false;
+
+ if (sd_device_get_ifindex(device, NULL) >= 0)
+ return false;
+
+ return true;
+ }
+
+ return (enumerator->match_initialized == MATCH_INITIALIZED_NO) == (r == 0);
+}
+
+static bool match_subsystem(sd_device_enumerator *enumerator, const char *subsystem) {
+ assert(enumerator);
+
+ if (!subsystem)
+ return false;
+
+ return set_fnmatch(enumerator->match_subsystem, enumerator->nomatch_subsystem, subsystem);
+}
+
+typedef enum MatchFlag {
+ MATCH_SYSNAME = 1u << 0,
+ MATCH_SUBSYSTEM = 1u << 1,
+ MATCH_PARENT = 1u << 2,
+ MATCH_TAG = 1u << 3,
+
+ MATCH_ALL = (1u << 4) - 1,
+} MatchFlag;
+
+static int test_matches(
+ sd_device_enumerator *enumerator,
+ sd_device *device,
+ MatchFlag flags) {
+
+ int r;
+
+ assert(enumerator);
+ assert(device);
+
+ if (FLAGS_SET(flags, MATCH_SYSNAME)) {
+ const char *sysname;
+
+ r = sd_device_get_sysname(device, &sysname);
+ if (r < 0)
+ return r;
+
+ if (!match_sysname(enumerator, sysname))
+ return false;
+ }
+
+ if (FLAGS_SET(flags, MATCH_SUBSYSTEM)) {
+ const char *subsystem;
+
+ r = sd_device_get_subsystem(device, &subsystem);
+ if (r == -ENOENT)
+ return false;
+ if (r < 0)
+ return r;
+
+ if (!match_subsystem(enumerator, subsystem))
+ return false;
+ }
+
+ if (FLAGS_SET(flags, MATCH_PARENT) &&
+ !device_match_parent(device, enumerator->match_parent, NULL))
+ return false;
+
+ if (FLAGS_SET(flags, MATCH_TAG) &&
+ !match_tag(enumerator, device))
+ return false;
+
+ r = match_initialized(enumerator, device);
+ if (r <= 0)
+ return r;
+
+ if (!match_property(enumerator, device))
+ return false;
+
+ if (!device_match_sysattr(device, enumerator->match_sysattr, enumerator->nomatch_sysattr))
+ return false;
+
+ return true;
+}
+
+static int enumerator_add_parent_devices(
+ sd_device_enumerator *enumerator,
+ sd_device *device,
+ MatchFlag flags) {
+
+ int k, r = 0;
+
+ assert(enumerator);
+ assert(device);
+
+ for (;;) {
+ k = sd_device_get_parent(device, &device);
+ if (k == -ENOENT) /* Reached the top? */
+ break;
+ if (k < 0) {
+ r = k;
+ break;
+ }
+
+ k = test_matches(enumerator, device, flags);
+ if (k < 0) {
+ r = k;
+ break;
+ }
+ if (k == 0)
+ continue;
+
+ k = device_enumerator_add_device(enumerator, device);
+ if (k < 0) {
+ r = k;
+ break;
+ }
+ if (k == 0) /* Exists already? Then no need to go further up. */
+ break;
+ }
+
+ return r;
+}
+
+int device_enumerator_add_parent_devices(sd_device_enumerator *enumerator, sd_device *device) {
+ return enumerator_add_parent_devices(enumerator, device, MATCH_ALL & (~MATCH_PARENT));
+}
+
+static bool relevant_sysfs_subdir(const struct dirent *de) {
+ assert(de);
+
+ if (de->d_name[0] == '.')
+ return false;
+
+ /* Also filter out regular files and such, i.e. stuff that definitely isn't a kobject path. (Note
+ * that we rely on the fact that sysfs fills in d_type here, i.e. doesn't do DT_UNKNOWN) */
+ return IN_SET(de->d_type, DT_DIR, DT_LNK);
+}
+
+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;
+ int k, 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) {
+ bool ignore = errno == ENOENT;
+
+ /* this is necessarily racey, so ignore missing directories */
+ log_debug_errno(errno,
+ "sd-device-enumerator: Failed to open directory %s%s: %m",
+ path, ignore ? ", ignoring" : "");
+ return ignore ? 0 : -errno;
+ }
+
+ FOREACH_DIRENT_ALL(de, dir, return -errno) {
+ _cleanup_(sd_device_unrefp) sd_device *device = NULL;
+ char syspath[strlen(path) + 1 + strlen(de->d_name) + 1];
+
+ if (!relevant_sysfs_subdir(de))
+ continue;
+
+ if (!match_sysname(enumerator, de->d_name))
+ continue;
+
+ (void) sprintf(syspath, "%s%s", path, de->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;
+ }
+
+ k = test_matches(enumerator, device, MATCH_ALL & (~MATCH_SYSNAME)); /* sysname is already tested. */
+ if (k <= 0) {
+ if (k < 0)
+ r = k;
+ continue;
+ }
+
+ k = device_enumerator_add_device(enumerator, device);
+ if (k < 0)
+ r = k;
+
+ /* Also include all potentially matching parent devices in the enumeration. These are things
+ * like root busses — e.g. /sys/devices/pci0000:00/ or /sys/devices/pnp0/, which ar not
+ * linked from /sys/class/ or /sys/bus/, hence pick them up explicitly here. */
+ k = enumerator_add_parent_devices(enumerator, device, MATCH_ALL);
+ if (k < 0)
+ r = k;
+ }
+
+ return r;
+}
+
+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;
+ int r = 0;
+
+ path = strjoina("/sys/", basedir);
+
+ dir = opendir(path);
+ if (!dir) {
+ bool ignore = errno == ENOENT;
+
+ log_debug_errno(errno,
+ "sd-device-enumerator: Failed to open directory %s%s: %m",
+ path, ignore ? ", ignoring" : "");
+ return ignore ? 0 : -errno;
+ }
+
+ FOREACH_DIRENT_ALL(de, dir, return -errno) {
+ int k;
+
+ if (!relevant_sysfs_subdir(de))
+ continue;
+
+ if (!match_subsystem(enumerator, subsystem ? : de->d_name))
+ continue;
+
+ k = enumerator_scan_dir_and_add_devices(enumerator, basedir, de->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;
+ int r = 0;
+
+ assert(enumerator);
+ assert(tag);
+
+ path = strjoina("/run/udev/tags/", tag);
+
+ dir = opendir(path);
+ if (!dir) {
+ bool ignore = errno == ENOENT;
+
+ log_debug_errno(errno,
+ "sd-device-enumerator: Failed to open directory %s%s: %m",
+ path, ignore ? ", ignoring" : "");
+ return ignore ? 0 : -errno;
+ }
+
+ /* TODO: filter away subsystems? */
+
+ FOREACH_DIRENT_ALL(de, dir, return -errno) {
+ _cleanup_(sd_device_unrefp) sd_device *device = NULL;
+ int k;
+
+ if (de->d_name[0] == '.')
+ continue;
+
+ k = sd_device_new_from_device_id(&device, de->d_name);
+ if (k < 0) {
+ if (k != -ENODEV)
+ /* this is necessarily racy, so ignore missing devices */
+ r = k;
+
+ continue;
+ }
+
+ /* Generated from tag, hence not necessary to check tag again. */
+ k = test_matches(enumerator, device, MATCH_ALL & (~MATCH_TAG));
+ if (k < 0)
+ r = k;
+ if (k <= 0)
+ 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;
+ int r = 0;
+
+ assert(enumerator);
+
+ SET_FOREACH(tag, enumerator->match_tag) {
+ 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, MatchFlag flags) {
+ _cleanup_(sd_device_unrefp) sd_device *device = NULL;
+ 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 = test_matches(enumerator, device, flags);
+ if (r <= 0)
+ return r;
+
+ return device_enumerator_add_device(enumerator, device);
+}
+
+static int parent_crawl_children(sd_device_enumerator *enumerator, const char *path, Set **stack) {
+ _cleanup_closedir_ DIR *dir = NULL;
+ int r = 0;
+
+ assert(enumerator);
+ assert(path);
+ assert(stack);
+
+ dir = opendir(path);
+ if (!dir) {
+ bool ignore = errno == ENOENT;
+
+ log_debug_errno(errno,
+ "sd-device-enumerator: Failed to open directory %s%s: %m",
+ path, ignore ? ", ignoring" : "");
+ return ignore ? 0 : -errno;
+ }
+
+ FOREACH_DIRENT_ALL(de, dir, return -errno) {
+ _cleanup_free_ char *child = NULL;
+ int k;
+
+ if (de->d_name[0] == '.')
+ continue;
+
+ if (de->d_type != DT_DIR)
+ continue;
+
+ child = path_join(path, de->d_name);
+ if (!child)
+ return -ENOMEM;
+
+ /* Let's check sysname filter earlier. The other tests require the sd-device object created
+ * from the path, thus much costly. */
+ if (match_sysname(enumerator, de->d_name)) {
+ k = parent_add_child(enumerator, child, MATCH_ALL & (~(MATCH_SYSNAME|MATCH_PARENT)));
+ if (k < 0)
+ r = k;
+ }
+
+ k = set_ensure_consume(stack, &path_hash_ops_free, TAKE_PTR(child));
+ if (k < 0)
+ r = k;
+ }
+
+ return r;
+}
+
+static int enumerator_scan_devices_children(sd_device_enumerator *enumerator) {
+ _cleanup_set_free_ Set *stack = NULL;
+ const char *path;
+ int r = 0, k;
+
+ assert(enumerator);
+
+ SET_FOREACH(path, enumerator->match_parent) {
+ k = parent_add_child(enumerator, path, MATCH_ALL & (~MATCH_PARENT));
+ if (k < 0)
+ r = k;
+
+ k = parent_crawl_children(enumerator, path, &stack);
+ if (k < 0)
+ r = k;
+ }
+
+ for (;;) {
+ _cleanup_free_ char *p = NULL;
+
+ p = set_steal_first(stack);
+ if (!p)
+ return r;
+
+ k = parent_crawl_children(enumerator, p, &stack);
+ if (k < 0)
+ r = k;
+ }
+}
+
+static int enumerator_scan_devices_all(sd_device_enumerator *enumerator) {
+ int k, r = 0;
+
+ k = enumerator_scan_dir(enumerator, "bus", "devices", NULL);
+ if (k < 0)
+ r = log_debug_errno(k, "sd-device-enumerator: Failed to scan /sys/bus: %m");
+
+ k = enumerator_scan_dir(enumerator, "class", NULL, NULL);
+ if (k < 0)
+ r = log_debug_errno(k, "sd-device-enumerator: Failed to scan /sys/class: %m");
+
+ return r;
+}
+
+int device_enumerator_scan_devices(sd_device_enumerator *enumerator) {
+ int r = 0, k;
+
+ assert(enumerator);
+
+ if (enumerator->scan_uptodate &&
+ enumerator->type == DEVICE_ENUMERATION_TYPE_DEVICES)
+ return 0;
+
+ device_enumerator_unref_devices(enumerator);
+
+ 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;
+ }
+
+ 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) {
+ assert_return(enumerator, NULL);
+
+ if (device_enumerator_scan_devices(enumerator) < 0)
+ return NULL;
+
+ if (enumerator_sort_devices(enumerator) < 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->sorted ||
+ 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) {
+ int r = 0, k;
+
+ assert(enumerator);
+
+ if (enumerator->scan_uptodate &&
+ enumerator->type == DEVICE_ENUMERATION_TYPE_SUBSYSTEMS)
+ return 0;
+
+ device_enumerator_unref_devices(enumerator);
+
+ /* modules */
+ if (match_subsystem(enumerator, "module")) {
+ k = enumerator_scan_dir_and_add_devices(enumerator, "module", NULL, NULL);
+ if (k < 0)
+ r = log_debug_errno(k, "sd-device-enumerator: Failed to scan modules: %m");
+ }
+
+ /* subsystems (only buses support coldplug) */
+ if (match_subsystem(enumerator, "subsystem")) {
+ k = enumerator_scan_dir_and_add_devices(enumerator, "bus", NULL, NULL);
+ if (k < 0)
+ r = log_debug_errno(k, "sd-device-enumerator: Failed to scan subsystems: %m");
+ }
+
+ /* subsystem drivers */
+ if (match_subsystem(enumerator, "drivers")) {
+ k = enumerator_scan_dir(enumerator, "bus", "drivers", "drivers");
+ if (k < 0)
+ r = log_debug_errno(k, "sd-device-enumerator: Failed to scan drivers: %m");
+ }
+
+ 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) {
+ assert_return(enumerator, NULL);
+
+ if (device_enumerator_scan_subsystems(enumerator) < 0)
+ return NULL;
+
+ if (enumerator_sort_devices(enumerator) < 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->sorted ||
+ enumerator->type != DEVICE_ENUMERATION_TYPE_SUBSYSTEMS ||
+ enumerator->current_device_index + 1 >= enumerator->n_devices)
+ return NULL;
+
+ return enumerator->devices[++enumerator->current_device_index];
+}
+
+int device_enumerator_scan_devices_and_subsystems(sd_device_enumerator *enumerator) {
+ int r;
+
+ assert(enumerator);
+
+ if (enumerator->scan_uptodate &&
+ enumerator->type == DEVICE_ENUMERATION_TYPE_ALL)
+ return 0;
+
+ device_enumerator_unref_devices(enumerator);
+
+ if (!set_isempty(enumerator->match_tag))
+ r = enumerator_scan_devices_tags(enumerator);
+ else if (enumerator->match_parent)
+ r = enumerator_scan_devices_children(enumerator);
+ else {
+ int k;
+
+ r = enumerator_scan_devices_all(enumerator);
+
+ if (match_subsystem(enumerator, "module")) {
+ k = enumerator_scan_dir_and_add_devices(enumerator, "module", NULL, NULL);
+ if (k < 0)
+ r = log_debug_errno(k, "sd-device-enumerator: Failed to scan modules: %m");
+ }
+ if (match_subsystem(enumerator, "subsystem")) {
+ k = enumerator_scan_dir_and_add_devices(enumerator, "bus", NULL, NULL);
+ if (k < 0)
+ r = log_debug_errno(k, "sd-device-enumerator: Failed to scan subsystems: %m");
+ }
+
+ if (match_subsystem(enumerator, "drivers")) {
+ k = enumerator_scan_dir(enumerator, "bus", "drivers", "drivers");
+ if (k < 0)
+ r = log_debug_errno(k, "sd-device-enumerator: Failed to scan drivers: %m");
+ }
+ }
+
+ enumerator->scan_uptodate = true;
+ enumerator->type = DEVICE_ENUMERATION_TYPE_ALL;
+
+ return r;
+}
+
+sd_device *device_enumerator_get_first(sd_device_enumerator *enumerator) {
+ assert_return(enumerator, NULL);
+
+ if (!enumerator->scan_uptodate)
+ return NULL;
+
+ if (enumerator_sort_devices(enumerator) < 0)
+ 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->sorted ||
+ 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;
+
+ if (enumerator_sort_devices(enumerator) < 0)
+ return NULL;
+
+ *ret_n_devices = enumerator->n_devices;
+ return enumerator->devices;
+}