diff options
Diffstat (limited to 'src/libsystemd/sd-device/device-enumerator.c')
-rw-r--r-- | src/libsystemd/sd-device/device-enumerator.c | 1175 |
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; +} |