udev: add builtin 'keyboard' to manage key mappings

Makefile.am

@@ -174,6 +174,7 @@ AM_CPPFLAGS = \
 	-I $(top_srcdir)/src/core \
 	-I $(top_srcdir)/src/libudev \
 	-I $(top_srcdir)/src/udev \
+	-I $(top_builddir)/src/udev \
 	-I $(top_srcdir)/src/libsystemd-bus \
 	$(OUR_CPPFLAGS)
 
@@ -2094,6 +2095,7 @@ dist_udevrules_DATA += \
 	rules/99-systemd.rules \
 	rules/42-usb-hid-pm.rules \
 	rules/50-udev-default.rules \
+	rules/60-keyboard.rules \
 	rules/60-persistent-storage-tape.rules \
 	rules/60-persistent-serial.rules \
 	rules/60-persistent-input.rules \
@@ -2157,6 +2159,19 @@ rootlibexec_PROGRAMS += \
 noinst_LTLIBRARIES += \
 	libudev-core.la
 
+src/udev/keyboard-keys.txt: Makefile
+	$(AM_V_at)$(MKDIR_P) $(dir $@)
+	$(AM_V_GEN)$(CPP) $(CFLAGS) $(AM_CPPFLAGS) $(CPPFLAGS) -dM -include linux/input.h - < /dev/null | $(AWK) '/^#define[ \t]+KEY_[^ ]+[ \t]+[0-9]/ { if ($$2 != "KEY_MAX") { print $$2 } }' | sed 's/^KEY_COFFEE$$/KEY_SCREENLOCK/' > $@
+
+src/udev/keyboard-keys-from-name.gperf: src/udev/keyboard-keys.txt Makefile
+	$(AM_V_GEN)$(AWK) 'BEGIN{ print "struct key { const char* name; unsigned short id; };"; print "%null-strings"; print "%%";} { print tolower(substr($$1 ,5)) ", " $$1 }' < $< > $@
+
+src/udev/keyboard-keys-from-name.h: src/udev/keyboard-keys-from-name.gperf Makefile
+	$(AM_V_GPERF)$(GPERF) -L ANSI-C -t -N keyboard_lookup_key -H hash_key_name -p -C < $< > $@
+
+src/udev/keyboard-keys-to-name.h: src/udev/keyboard-keys.txt Makefile
+	$(AM_V_GEN)$(AWK) 'BEGIN{ print "const char* const key_names[KEY_CNT] = { "} { print "[" $$1 "] = \"" $$1 "\"," } END{print "};"}' < $< > $@
+
 libudev_core_la_SOURCES = \
 	src/udev/udev.h \
 	src/udev/udev-event.c \
@@ -2168,10 +2183,22 @@ libudev_core_la_SOURCES = \
 	src/udev/udev-builtin-btrfs.c \
 	src/udev/udev-builtin-hwdb.c \
 	src/udev/udev-builtin-input_id.c \
+	src/udev/udev-builtin-keyboard.c \
 	src/udev/udev-builtin-net_id.c \
 	src/udev/udev-builtin-path_id.c \
 	src/udev/udev-builtin-usb_id.c
 
+nodist_libudev_core_la_SOURCES = \
+	src/udev/keyboard-keys-from-name.h \
+	src/udev/keyboard-keys-to-name.h
+
+BUILT_SOURCES += \
+	$(nodist_libudev_core_la_SOURCES)
+
+CLEANFILES += \
+	src/udev/keyboard-keys-from-name.gperf \
+	src/udev/keyboard-keys.txt
+
 libudev_core_la_CFLAGS = \
 	$(AM_CFLAGS) \
 	$(BLKID_CFLAGS) \

rules/60-keyboard.rules

@@ -0,0 +1,22 @@
+# do not edit this file, it will be overwritten on update
+
+ACTION!="add", GOTO="keyboard_end"
+KERNEL!="event*", GOTO="keyboard_end"
+ENV{ID_INPUT_KEY}=="", GOTO="keyboard_end"
+
+# ignore all bluetooth devices
+SUBSYSTEMS=="bluetooth", GOTO="keyboard_end"
+
+# import key mapping for USB device
+SUBSYSTEMS=="usb", IMPORT{builtin}="hwdb --subsystem=usb --lookup-prefix=keyboard:", \
+  RUN{program}+="keyboard", GOTO="keyboard_end"
+
+# import key mapping for AT keyboard from DMI data
+DRIVERS=="atkbd", IMPORT{builtin}="hwdb 'keyboard:$attr{[dmi/id]modalias}'", \
+  RUN{program}+="keyboard", GOTO="keyboard_end"
+
+# import key mapping for platform input device
+KERNELS=="input*", IMPORT{builtin}="hwdb 'keyboard:name:$attr{name}:$attr{[dmi/id]modalias}'", \
+  RUN{program}+="keyboard", GOTO="keyboard_end"
+
+LABEL="keyboard_end"

shell-completion/bash/udevadm

@@ -93,7 +93,7 @@ _udevadm() {
                 fi
 
         elif __contains_word "$verb" ${VERBS[TESTBUILTIN]}; then
-                      comps='blkid btrfs hwdb input_id kmod net_id path_id usb_id uaccess'
+                      comps='blkid btrfs hwdb input_id keyboard kmod net_id path_id usb_id uaccess'
         fi
 
         COMPREPLY=( $(compgen -W '$comps' -- "$cur") )

src/udev/.gitignore

@@ -1 +1,5 @@
 /udev.pc
+/keyboard-keys-from-name.gperf
+/keyboard-keys-from-name.h
+/keyboard-keys-to-name.h
+/keyboard-keys.txt

src/udev/udev-builtin-keyboard.c

@@ -0,0 +1,163 @@
+/***
+  This file is part of systemd.
+
+  Copyright 2013 Kay Sievers <kay@vrfy.org>
+
+  systemd is free software; you can redistribute it and/or modify it
+  under the terms of the GNU Lesser General Public License as published by
+  the Free Software Foundation; either version 2.1 of the License, or
+  (at your option) any later version.
+
+  systemd is distributed in the hope that it will be useful, but
+  WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public License
+  along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <stdio.h>
+#include <errno.h>
+#include <string.h>
+#include <stdlib.h>
+#include <fcntl.h>
+#include <sys/ioctl.h>
+#include <linux/limits.h>
+#include <linux/input.h>
+
+#include "udev.h"
+
+static const struct key *keyboard_lookup_key(const char *str, unsigned int len);
+#include "keyboard-keys-from-name.h"
+#include "keyboard-keys-to-name.h"
+
+static int install_force_release(struct udev_device *dev, const unsigned int *release, unsigned int release_count) {
+        struct udev_device *atkbd;
+        const char *cur;
+        char codes[4096];
+        char *s;
+        size_t l;
+        unsigned int i;
+        int ret;
+
+        atkbd = udev_device_get_parent_with_subsystem_devtype(dev, "serio", NULL);
+        if (!atkbd)
+                return -ENODEV;
+
+        cur = udev_device_get_sysattr_value(atkbd, "force_release");
+        if (!cur)
+                return -ENODEV;
+
+        s = codes;
+        l = sizeof(codes);
+
+        /* copy current content */
+        l = strpcpy(&s, l, cur);
+
+        /* append new codes */
+        for (i = 0; i < release_count; i++)
+                l = strpcpyf(&s, l, ",%d", release[i]);
+
+        log_debug("keyboard: updating force-release list with '%s'\n", codes);
+        ret = udev_device_set_sysattr_value(atkbd, "force_release", codes);
+        if (ret < 0)
+                log_error("Error writing force-release attribute: %s", strerror(-ret));
+        return ret;
+}
+
+static int builtin_keyboard(struct udev_device *dev, int argc, char *argv[], bool test) {
+        struct udev_list_entry *entry;
+        struct {
+                unsigned int scan;
+                unsigned int key;
+        } map[1024];
+        unsigned int map_count = 0;
+        unsigned int release[1024];
+        unsigned int release_count = 0;
+
+        udev_list_entry_foreach(entry, udev_device_get_properties_list_entry(dev)) {
+                const char *key;
+                unsigned int scancode;
+                char *endptr;
+                const char *keycode;
+                const struct key *k;
+
+                key = udev_list_entry_get_name(entry);
+                if (!startswith(key, "KEYBOARD_KEY_"))
+                        continue;
+
+                /* KEYBOARD_KEY_<hex scan code>=<key identifier string> */
+                scancode = strtol(key + 13, &endptr, 16);
+                if (endptr[0] != '\0') {
+                        log_error("Error, unable to parse scan code from '%s'\n", key);
+                        continue;
+                }
+
+                keycode = udev_list_entry_get_value(entry);
+
+                /* a leading '!' needs a force-release entry */
+                if (keycode[0] == '!') {
+                        keycode++;
+
+                        release[release_count] = scancode;
+                        if (release_count <  ELEMENTSOF(release)-1)
+                                release_count++;
+
+                        if (keycode[0] == '\0')
+                                continue;
+                }
+
+                /* translate identifier to key code */
+                k = keyboard_lookup_key(keycode, strlen(keycode));
+                if (!k) {
+                        log_error("Error, unknown key identifier '%s'\n", keycode);
+                        continue;
+                }
+
+                map[map_count].scan = scancode;
+                map[map_count].key = k->id;
+                if (map_count < ELEMENTSOF(map)-1)
+                        map_count++;
+        }
+
+        if (map_count > 0 || release_count > 0) {
+                const char *node;
+                int fd;
+                unsigned int i;
+
+                node = udev_device_get_devnode(dev);
+                if (!node) {
+                        log_error("Error, no device node for '%s'\n", udev_device_get_syspath(dev));
+                        return EXIT_FAILURE;
+                }
+
+                fd = open(udev_device_get_devnode(dev), O_RDWR|O_CLOEXEC|O_NONBLOCK|O_NOCTTY);
+                if (fd < 0) {
+                        log_error("Error, opening device '%s': %m\n", node);
+                        return EXIT_FAILURE;
+                }
+
+                /* install list of map codes */
+                for (i = 0; i < map_count; i++) {
+                        log_debug("keyboard: mapping scan code %d (0x%x) to key code %d (0x%x)\n",
+                                  map[i].scan, map[i].scan, map[i].key, map[i].key);
+                        if (ioctl(fd, EVIOCSKEYCODE, &map[i]) < 0)
+                                log_error("Error calling EVIOCSKEYCODE: %m\n");
+                }
+
+                /* install list of force-release codes */
+                if (release_count > 0)
+                        install_force_release(dev, release, release_count);
+
+                close(fd);
+        }
+
+        return EXIT_SUCCESS;
+}
+
+const struct udev_builtin udev_builtin_keyboard = {
+        .name = "keyboard",
+        .cmd = builtin_keyboard,
+        .help = "keyboard scan code to key mapping",
+};

src/udev/udev-builtin.c

@@ -39,6 +39,7 @@ static const struct udev_builtin *builtins[] = {
 #endif
         [UDEV_BUILTIN_HWDB] = &udev_builtin_hwdb,
         [UDEV_BUILTIN_INPUT_ID] = &udev_builtin_input_id,
+        [UDEV_BUILTIN_KEYBOARD] = &udev_builtin_keyboard,
 #ifdef HAVE_KMOD
         [UDEV_BUILTIN_KMOD] = &udev_builtin_kmod,
 #endif

src/udev/udev.h

@@ -145,6 +145,7 @@ enum udev_builtin_cmd {
 #endif
         UDEV_BUILTIN_HWDB,
         UDEV_BUILTIN_INPUT_ID,
+        UDEV_BUILTIN_KEYBOARD,
 #ifdef HAVE_KMOD
         UDEV_BUILTIN_KMOD,
 #endif
@@ -174,6 +175,7 @@ extern const struct udev_builtin udev_builtin_firmware;
 #endif
 extern const struct udev_builtin udev_builtin_hwdb;
 extern const struct udev_builtin udev_builtin_input_id;
+extern const struct udev_builtin udev_builtin_keyboard;
 #ifdef HAVE_KMOD
 extern const struct udev_builtin udev_builtin_kmod;
 #endif