blob: 2dc695bd03f9813c0b4b3d7e61525cc04b20fd05 [file] [log] [blame]
/* SPDX-License-Identifier: LGPL-2.1-or-later */
#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"
#include "libudev-list-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;
_cleanup_(udev_list_freep) struct udev_list *list = 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);
list = udev_list_new(false);
if (!list)
return_with_errno(NULL, ENOMEM);
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),
.devices_list = TAKE_PTR(list),
};
return udev_enumerate;
}
static struct udev_enumerate *udev_enumerate_free(struct udev_enumerate *udev_enumerate) {
assert(udev_enumerate);
udev_list_free(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 an 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) {
int r;
assert_return(udev_enumerate, -EINVAL);
if (!subsystem)
return 0;
r = sd_device_enumerator_add_match_subsystem(udev_enumerate->enumerator, subsystem, true);
if (r < 0)
return r;
udev_enumerate->devices_uptodate = false;
return 0;
}
/**
* 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) {
int r;
assert_return(udev_enumerate, -EINVAL);
if (!subsystem)
return 0;
r = sd_device_enumerator_add_match_subsystem(udev_enumerate->enumerator, subsystem, false);
if (r < 0)
return r;
udev_enumerate->devices_uptodate = false;
return 0;
}
/**
* 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) {
int r;
assert_return(udev_enumerate, -EINVAL);
if (!sysattr)
return 0;
r = sd_device_enumerator_add_match_sysattr(udev_enumerate->enumerator, sysattr, value, true);
if (r < 0)
return r;
udev_enumerate->devices_uptodate = false;
return 0;
}
/**
* 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) {
int r;
assert_return(udev_enumerate, -EINVAL);
if (!sysattr)
return 0;
r = sd_device_enumerator_add_match_sysattr(udev_enumerate->enumerator, sysattr, value, false);
if (r < 0)
return r;
udev_enumerate->devices_uptodate = false;
return 0;
}
/**
* 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) {
int r;
assert_return(udev_enumerate, -EINVAL);
if (!property)
return 0;
r = sd_device_enumerator_add_match_property(udev_enumerate->enumerator, property, value);
if (r < 0)
return r;
udev_enumerate->devices_uptodate = false;
return 0;
}
/**
* 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) {
int r;
assert_return(udev_enumerate, -EINVAL);
if (!tag)
return 0;
r = sd_device_enumerator_add_match_tag(udev_enumerate->enumerator, tag);
if (r < 0)
return r;
udev_enumerate->devices_uptodate = false;
return 0;
}
/**
* 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.
*
* 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) {
int r;
assert_return(udev_enumerate, -EINVAL);
if (!parent)
return 0;
r = sd_device_enumerator_add_match_parent(udev_enumerate->enumerator, udev_device_get_sd_device(parent));
if (r < 0)
return r;
udev_enumerate->devices_uptodate = false;
return 0;
}
/**
* 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) {
int r;
assert_return(udev_enumerate, -EINVAL);
r = device_enumerator_add_match_is_initialized(udev_enumerate->enumerator);
if (r < 0)
return r;
udev_enumerate->devices_uptodate = false;
return 0;
}
/**
* 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) {
int r;
assert_return(udev_enumerate, -EINVAL);
if (!sysname)
return 0;
r = sd_device_enumerator_add_match_sysname(udev_enumerate->enumerator, sysname);
if (r < 0)
return r;
udev_enumerate->devices_uptodate = false;
return 0;
}
/**
* 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;
udev_enumerate->devices_uptodate = false;
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);
}