src/udev/udev-builtin-keyboard.c

   1 /***
   2   This file is part of systemd.
   3
   4   Copyright 2013 Kay Sievers <kay@vrfy.org>
   5
   6   systemd is free software; you can redistribute it and/or modify it
   7   under the terms of the GNU Lesser General Public License as published by
   8   the Free Software Foundation; either version 2.1 of the License, or
   9   (at your option) any later version.
  10
  11   systemd is distributed in the hope that it will be useful, but
  12   WITHOUT ANY WARRANTY; without even the implied warranty of
  13   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  14   Lesser General Public License for more details.
  15
  16   You should have received a copy of the GNU Lesser General Public License
  17   along with systemd; If not, see <http://www.gnu.org/licenses/>.
  18 ***/
  19
  20 #include <stdio.h>
  21 #include <errno.h>
  22 #include <string.h>
  23 #include <stdlib.h>
  24 #include <fcntl.h>
  25 #include <sys/ioctl.h>
  26 #include <linux/limits.h>
  27 #include <linux/input.h>
  28
  29 #include "udev.h"
  30
  31 static const struct key *keyboard_lookup_key(const char *str, unsigned int len);
  32 #include "keyboard-keys-from-name.h"
  33 #include "keyboard-keys-to-name.h"
  34
  35 static int install_force_release(struct udev_device *dev, const unsigned int *release, unsigned int release_count) {
  36         struct udev_device *atkbd;
  37         const char *cur;
  38         char codes[4096];
  39         char *s;
  40         size_t l;
  41         unsigned int i;
  42         int ret;
  43
  44         atkbd = udev_device_get_parent_with_subsystem_devtype(dev, "serio", NULL);
  45         if (!atkbd)
  46                 return -ENODEV;
  47
  48         cur = udev_device_get_sysattr_value(atkbd, "force_release");
  49         if (!cur)
  50                 return -ENODEV;
  51
  52         s = codes;
  53         l = sizeof(codes);
  54
  55         /* copy current content */
  56         l = strpcpy(&s, l, cur);
  57
  58         /* append new codes */
  59         for (i = 0; i < release_count; i++)
  60                 l = strpcpyf(&s, l, ",%d", release[i]);
  61
  62         log_debug("keyboard: updating force-release list with '%s'\n", codes);
  63         ret = udev_device_set_sysattr_value(atkbd, "force_release", codes);
  64         if (ret < 0)
  65                 log_error("Error writing force-release attribute: %s", strerror(-ret));
  66         return ret;
  67 }
  68
  69 static int builtin_keyboard(struct udev_device *dev, int argc, char *argv[], bool test) {
  70         struct udev_list_entry *entry;
  71         struct {
  72                 unsigned int scan;
  73                 unsigned int key;
  74         } map[1024];
  75         unsigned int map_count = 0;
  76         unsigned int release[1024];
  77         unsigned int release_count = 0;
  78
  79         udev_list_entry_foreach(entry, udev_device_get_properties_list_entry(dev)) {
  80                 const char *key;
  81                 unsigned int scancode;
  82                 char *endptr;
  83                 const char *keycode;
  84                 const struct key *k;
  85
  86                 key = udev_list_entry_get_name(entry);
  87                 if (!startswith(key, "KEYBOARD_KEY_"))
  88                         continue;
  89
  90                 /* KEYBOARD_KEY_<hex scan code>=<key identifier string> */
  91                 scancode = strtol(key + 13, &endptr, 16);
  92                 if (endptr[0] != '\0') {
  93                         log_error("Error, unable to parse scan code from '%s'\n", key);
  94                         continue;
  95                 }
  96
  97                 keycode = udev_list_entry_get_value(entry);
  98
  99                 /* a leading '!' needs a force-release entry */
 100                 if (keycode[0] == '!') {
 101                         keycode++;
 102
 103                         release[release_count] = scancode;
 104                         if (release_count <  ELEMENTSOF(release)-1)
 105                                 release_count++;
 106
 107                         if (keycode[0] == '\0')
 108                                 continue;
 109                 }
 110
 111                 /* translate identifier to key code */
 112                 k = keyboard_lookup_key(keycode, strlen(keycode));
 113                 if (!k) {
 114                         log_error("Error, unknown key identifier '%s'\n", keycode);
 115                         continue;
 116                 }
 117
 118                 map[map_count].scan = scancode;
 119                 map[map_count].key = k->id;
 120                 if (map_count < ELEMENTSOF(map)-1)
 121                         map_count++;
 122         }
 123
 124         if (map_count > 0 || release_count > 0) {
 125                 const char *node;
 126                 int fd;
 127                 unsigned int i;
 128
 129                 node = udev_device_get_devnode(dev);
 130                 if (!node) {
 131                         log_error("Error, no device node for '%s'\n", udev_device_get_syspath(dev));
 132                         return EXIT_FAILURE;
 133                 }
 134
 135                 fd = open(udev_device_get_devnode(dev), O_RDWR|O_CLOEXEC|O_NONBLOCK|O_NOCTTY);
 136                 if (fd < 0) {
 137                         log_error("Error, opening device '%s': %m\n", node);
 138                         return EXIT_FAILURE;
 139                 }
 140
 141                 /* install list of map codes */
 142                 for (i = 0; i < map_count; i++) {
 143                         log_debug("keyboard: mapping scan code %d (0x%x) to key code %d (0x%x)\n",
 144                                   map[i].scan, map[i].scan, map[i].key, map[i].key);
 145                         if (ioctl(fd, EVIOCSKEYCODE, &map[i]) < 0)
 146                                 log_error("Error calling EVIOCSKEYCODE: %m\n");
 147                 }
 148
 149                 /* install list of force-release codes */
 150                 if (release_count > 0)
 151                         install_force_release(dev, release, release_count);
 152
 153                 close(fd);
 154         }
 155
 156         return EXIT_SUCCESS;
 157 }
 158
 159 const struct udev_builtin udev_builtin_keyboard = {
 160         .name = "keyboard",
 161         .cmd = builtin_keyboard,
 162         .help = "keyboard scan code to key mapping",
 163 };