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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 02:25:50 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 02:25:50 +0000 |
commit | 19f4f86bfed21c5326ed2acebe1163f3a83e832b (patch) | |
tree | d59b9989ce55ed23693e80974d94c856f1c2c8b1 /src/libudev/libudev-enumerate.c | |
parent | Initial commit. (diff) | |
download | systemd-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/libudev/libudev-enumerate.c')
-rw-r--r-- | src/libudev/libudev-enumerate.c | 392 |
1 files changed, 392 insertions, 0 deletions
diff --git a/src/libudev/libudev-enumerate.c b/src/libudev/libudev-enumerate.c new file mode 100644 index 0000000..e54ee57 --- /dev/null +++ b/src/libudev/libudev-enumerate.c @@ -0,0 +1,392 @@ +/* SPDX-License-Identifier: LGPL-2.1+ */ + +#include <dirent.h> +#include <errno.h> +#include <fnmatch.h> +#include <stdbool.h> +#include <stddef.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <sys/stat.h> + +#include "libudev.h" +#include "sd-device.h" + +#include "alloc-util.h" +#include "device-enumerator-private.h" +#include "device-util.h" +#include "libudev-device-internal.h" + +/** + * SECTION:libudev-enumerate + * @short_description: lookup and sort sys devices + * + * Lookup devices in the sys filesystem, filter devices by properties, + * and return a sorted list of devices. + */ + +/** + * udev_enumerate: + * + * Opaque object representing one device lookup/sort context. + */ +struct udev_enumerate { + struct udev *udev; + unsigned n_ref; + struct udev_list devices_list; + bool devices_uptodate:1; + + sd_device_enumerator *enumerator; +}; + +/** + * udev_enumerate_new: + * @udev: udev library context + * + * Create an enumeration context to scan /sys. + * + * Returns: an enumeration context. + **/ +_public_ struct udev_enumerate *udev_enumerate_new(struct udev *udev) { + _cleanup_(sd_device_enumerator_unrefp) sd_device_enumerator *e = NULL; + struct udev_enumerate *udev_enumerate; + int r; + + r = sd_device_enumerator_new(&e); + if (r < 0) + return_with_errno(NULL, r); + + r = sd_device_enumerator_allow_uninitialized(e); + if (r < 0) + return_with_errno(NULL, r); + + udev_enumerate = new(struct udev_enumerate, 1); + if (!udev_enumerate) + return_with_errno(NULL, ENOMEM); + + *udev_enumerate = (struct udev_enumerate) { + .udev = udev, + .n_ref = 1, + .enumerator = TAKE_PTR(e), + }; + + udev_list_init(&udev_enumerate->devices_list, false); + + return udev_enumerate; +} + +static struct udev_enumerate *udev_enumerate_free(struct udev_enumerate *udev_enumerate) { + assert(udev_enumerate); + + udev_list_cleanup(&udev_enumerate->devices_list); + sd_device_enumerator_unref(udev_enumerate->enumerator); + return mfree(udev_enumerate); +} + +/** + * udev_enumerate_ref: + * @udev_enumerate: context + * + * Take a reference of a enumeration context. + * + * Returns: the passed enumeration context + **/ + +/** + * udev_enumerate_unref: + * @udev_enumerate: context + * + * Drop a reference of an enumeration context. If the refcount reaches zero, + * all resources of the enumeration context will be released. + * + * Returns: #NULL + **/ +DEFINE_PUBLIC_TRIVIAL_REF_UNREF_FUNC(struct udev_enumerate, udev_enumerate, udev_enumerate_free); + +/** + * udev_enumerate_get_udev: + * @udev_enumerate: context + * + * Get the udev library context. + * + * Returns: a pointer to the context. + */ +_public_ struct udev *udev_enumerate_get_udev(struct udev_enumerate *udev_enumerate) { + assert_return_errno(udev_enumerate, NULL, EINVAL); + + return udev_enumerate->udev; +} + +/** + * udev_enumerate_get_list_entry: + * @udev_enumerate: context + * + * Get the first entry of the sorted list of device paths. + * + * Returns: a udev_list_entry. + */ +_public_ struct udev_list_entry *udev_enumerate_get_list_entry(struct udev_enumerate *udev_enumerate) { + struct udev_list_entry *e; + + assert_return_errno(udev_enumerate, NULL, EINVAL); + + if (!udev_enumerate->devices_uptodate) { + sd_device *device; + + udev_list_cleanup(&udev_enumerate->devices_list); + + FOREACH_DEVICE_AND_SUBSYSTEM(udev_enumerate->enumerator, device) { + const char *syspath; + int r; + + r = sd_device_get_syspath(device, &syspath); + if (r < 0) + return_with_errno(NULL, r); + + if (!udev_list_entry_add(&udev_enumerate->devices_list, syspath, NULL)) + return_with_errno(NULL, ENOMEM); + } + + udev_enumerate->devices_uptodate = true; + } + + e = udev_list_get_entry(&udev_enumerate->devices_list); + if (!e) + return_with_errno(NULL, ENODATA); + + return e; +} + +/** + * udev_enumerate_add_match_subsystem: + * @udev_enumerate: context + * @subsystem: filter for a subsystem of the device to include in the list + * + * Match only devices belonging to a certain kernel subsystem. + * + * Returns: 0 on success, otherwise a negative error value. + */ +_public_ int udev_enumerate_add_match_subsystem(struct udev_enumerate *udev_enumerate, const char *subsystem) { + assert_return(udev_enumerate, -EINVAL); + + if (!subsystem) + return 0; + + return sd_device_enumerator_add_match_subsystem(udev_enumerate->enumerator, subsystem, true); +} + +/** + * udev_enumerate_add_nomatch_subsystem: + * @udev_enumerate: context + * @subsystem: filter for a subsystem of the device to exclude from the list + * + * Match only devices not belonging to a certain kernel subsystem. + * + * Returns: 0 on success, otherwise a negative error value. + */ +_public_ int udev_enumerate_add_nomatch_subsystem(struct udev_enumerate *udev_enumerate, const char *subsystem) { + assert_return(udev_enumerate, -EINVAL); + + if (!subsystem) + return 0; + + return sd_device_enumerator_add_match_subsystem(udev_enumerate->enumerator, subsystem, false); +} + +/** + * udev_enumerate_add_match_sysattr: + * @udev_enumerate: context + * @sysattr: filter for a sys attribute at the device to include in the list + * @value: optional value of the sys attribute + * + * Match only devices with a certain /sys device attribute. + * + * Returns: 0 on success, otherwise a negative error value. + */ +_public_ int udev_enumerate_add_match_sysattr(struct udev_enumerate *udev_enumerate, const char *sysattr, const char *value) { + assert_return(udev_enumerate, -EINVAL); + + if (!sysattr) + return 0; + + return sd_device_enumerator_add_match_sysattr(udev_enumerate->enumerator, sysattr, value, true); +} + +/** + * udev_enumerate_add_nomatch_sysattr: + * @udev_enumerate: context + * @sysattr: filter for a sys attribute at the device to exclude from the list + * @value: optional value of the sys attribute + * + * Match only devices not having a certain /sys device attribute. + * + * Returns: 0 on success, otherwise a negative error value. + */ +_public_ int udev_enumerate_add_nomatch_sysattr(struct udev_enumerate *udev_enumerate, const char *sysattr, const char *value) { + assert_return(udev_enumerate, -EINVAL); + + if (!sysattr) + return 0; + + return sd_device_enumerator_add_match_sysattr(udev_enumerate->enumerator, sysattr, value, false); +} + +/** + * udev_enumerate_add_match_property: + * @udev_enumerate: context + * @property: filter for a property of the device to include in the list + * @value: value of the property + * + * Match only devices with a certain property. + * + * Returns: 0 on success, otherwise a negative error value. + */ +_public_ int udev_enumerate_add_match_property(struct udev_enumerate *udev_enumerate, const char *property, const char *value) { + assert_return(udev_enumerate, -EINVAL); + + if (!property) + return 0; + + return sd_device_enumerator_add_match_property(udev_enumerate->enumerator, property, value); +} + +/** + * udev_enumerate_add_match_tag: + * @udev_enumerate: context + * @tag: filter for a tag of the device to include in the list + * + * Match only devices with a certain tag. + * + * Returns: 0 on success, otherwise a negative error value. + */ +_public_ int udev_enumerate_add_match_tag(struct udev_enumerate *udev_enumerate, const char *tag) { + assert_return(udev_enumerate, -EINVAL); + + if (!tag) + return 0; + + return sd_device_enumerator_add_match_tag(udev_enumerate->enumerator, tag); +} + +/** + * udev_enumerate_add_match_parent: + * @udev_enumerate: context + * @parent: parent device where to start searching + * + * Return the devices on the subtree of one given device. The parent + * itself is included in the list. + * + * A reference for the device is held until the udev_enumerate context + * is cleaned up. + * + * Returns: 0 on success, otherwise a negative error value. + */ +_public_ int udev_enumerate_add_match_parent(struct udev_enumerate *udev_enumerate, struct udev_device *parent) { + assert_return(udev_enumerate, -EINVAL); + + if (!parent) + return 0; + + return sd_device_enumerator_add_match_parent(udev_enumerate->enumerator, parent->device); +} + +/** + * udev_enumerate_add_match_is_initialized: + * @udev_enumerate: context + * + * Match only devices which udev has set up already. This makes + * sure, that the device node permissions and context are properly set + * and that network devices are fully renamed. + * + * Usually, devices which are found in the kernel but not already + * handled by udev, have still pending events. Services should subscribe + * to monitor events and wait for these devices to become ready, instead + * of using uninitialized devices. + * + * For now, this will not affect devices which do not have a device node + * and are not network interfaces. + * + * Returns: 0 on success, otherwise a negative error value. + */ +_public_ int udev_enumerate_add_match_is_initialized(struct udev_enumerate *udev_enumerate) { + assert_return(udev_enumerate, -EINVAL); + + return device_enumerator_add_match_is_initialized(udev_enumerate->enumerator); +} + +/** + * udev_enumerate_add_match_sysname: + * @udev_enumerate: context + * @sysname: filter for the name of the device to include in the list + * + * Match only devices with a given /sys device name. + * + * Returns: 0 on success, otherwise a negative error value. + */ +_public_ int udev_enumerate_add_match_sysname(struct udev_enumerate *udev_enumerate, const char *sysname) { + assert_return(udev_enumerate, -EINVAL); + + if (!sysname) + return 0; + + return sd_device_enumerator_add_match_sysname(udev_enumerate->enumerator, sysname); +} + +/** + * udev_enumerate_add_syspath: + * @udev_enumerate: context + * @syspath: path of a device + * + * Add a device to the list of devices, to retrieve it back sorted in dependency order. + * + * Returns: 0 on success, otherwise a negative error value. + */ +_public_ int udev_enumerate_add_syspath(struct udev_enumerate *udev_enumerate, const char *syspath) { + _cleanup_(sd_device_unrefp) sd_device *device = NULL; + int r; + + assert_return(udev_enumerate, -EINVAL); + + if (!syspath) + return 0; + + r = sd_device_new_from_syspath(&device, syspath); + if (r < 0) + return r; + + r = device_enumerator_add_device(udev_enumerate->enumerator, device); + if (r < 0) + return r; + + return 0; +} + +/** + * udev_enumerate_scan_devices: + * @udev_enumerate: udev enumeration context + * + * Scan /sys for all devices which match the given filters. No matches + * will return all currently available devices. + * + * Returns: 0 on success, otherwise a negative error value. + **/ +_public_ int udev_enumerate_scan_devices(struct udev_enumerate *udev_enumerate) { + assert_return(udev_enumerate, -EINVAL); + + return device_enumerator_scan_devices(udev_enumerate->enumerator); +} + +/** + * udev_enumerate_scan_subsystems: + * @udev_enumerate: udev enumeration context + * + * Scan /sys for all kernel subsystems, including buses, classes, drivers. + * + * Returns: 0 on success, otherwise a negative error value. + **/ +_public_ int udev_enumerate_scan_subsystems(struct udev_enumerate *udev_enumerate) { + assert_return(udev_enumerate, -EINVAL); + + return device_enumerator_scan_subsystems(udev_enumerate->enumerator); +} |