keventd is the only thing in the tree that links libblkid, so a tree
that used to build now stops in configure with no hint of which package
to install. Say so where people look for dependencies, and give CI the
package it now needs.
Signed-off-by: Joachim Wiberg <troglobit@gmail.com>
Add 27 stock rules installed to /lib/udev/rules.d/. Rules invoking
/lib/udev/<helper> fall back to keventd builtins (path_id, usb_id,
blkid, hwdb, kmod, net_id, input_id) when the helper binary is absent;
user-supplied helpers in /lib/udev/ still take precedence.
Signed-off-by: Joachim Wiberg <troglobit@gmail.com>
Transform keventd from a power-supply monitor + basic hotplug handler into
a full udev-compatible device manager.
Rules engine (rules.c):
- Full .rules file parser covering all udev key types: ACTION, KERNEL,
SUBSYSTEM, DEVPATH, ENV, ATTR, SYSCTL, TAG, RESULT, PROGRAM, TEST,
parent-chain KERNELS/SUBSYSTEMS/ATTRS/DRIVERS, and more
- Pattern matching: plain string, fnmatch glob, and pipe-separated alternatives
- Operators: ==, !=, =, +=, -=, :=
- Assignments: NAME=, MODE=, OWNER=, GROUP=, SYMLINK+=, ENV{k}=, TAG+=, RUN+=
- IMPORT{program|file|builtin|parent|cmdline|db}=
- PROGRAM= with stdout capture for subsequent RESULT== matching
- GOTO=/LABEL= flow control
- Loads *.rules from /lib/udev/rules.d, /run/udev/rules.d, /etc/udev/rules.d
and an optional extra directory (-r DIR); reloads on SIGHUP
Builtin framework (builtin.c):
- kmod: load module by MODALIAS or explicit alias
- hwdb: match device against *.hwdb text files in udev hwdb dirs; builds
correct lookup key per subsystem — evdev:input:b*v*p*e* for input,
usb:v*p* for USB, raw modalias for PCI/platform
- path_id: build stable ID_PATH / ID_PATH_TAG from sysfs topology (PCI, USB,
ATA, NVMe, platform, ACPI, virtio)
- usb_id: read idVendor/idProduct/bcdDevice/serial from sysfs; look up
ID_VENDOR_FROM_DATABASE and ID_MODEL_FROM_DATABASE from usb.ids
(hwdata package) when available; silent fallback when absent
- input_id: classify input devices (keyboard, mouse, joystick, touchscreen,
touchpad) from evdev capability bitmasks in sysfs
- net_id: generate predictable names — MAC-based enx<mac> and PCI-slot-based
enp<bus>s<dev>[f<func>]
- blkid: probe filesystem type, UUID, and label via libblkid; sets ID_FS_*
and ID_PART_TABLE_* properties
Network interface renaming (uevent.c):
- netdev_add() renames interfaces via SIOCSIFNAME when a NAME= rule matched,
then sets the Finit dev/ condition on the final name; and any setup using
persistent interface naming via udev rules
Device node and symlink improvements (uevent.c):
- NAME=, MODE=, OWNER=, GROUP= overrides from matched rules applied at
mknod/chown time, falling back to the built-in permission table
- SYMLINK+= links from rules applied alongside built-in by-id/by-path links
Device property database (udevdb.c):
- Persist per-device E:/S:/I: records to /run/udev/data/ on ADD/CHANGE,
delete on REMOVE; IMPORT{db}= restores saved properties into event env
Build:
- libblkid (util-linux) is now required for keventd
Signed-off-by: Joachim Wiberg <troglobit@gmail.com>
This is a backwards compatible mode for users upgrading and not noticing
that keventd is now build by default.
Signed-off-by: Joachim Wiberg <troglobit@gmail.com>
Rewrite doc/keventd.md from a 14-line stub into comprehensive
documentation covering all features of the new unified keventd:
device node creation, persistent symlinks, firmware loading,
module loading, coldplug, conditions, and command-line usage.
Update doc/conditions.md to list keventd as the primary provider
of dev/* and sys/pwr/* conditions, with devmon as fallback when
an external device manager is used instead.
Signed-off-by: Joachim Wiberg <troglobit@gmail.com>
Joachim Wiberg