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-rw-r--r--src/libudev/libudev-enumerate.c392
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);
+}