src/uterm_input_uxkb.c

   1 /*
   2  * uterm - Linux User-Space Terminal
   3  *
   4  * Copyright (c) 2011 Ran Benita <ran234@gmail.com>
   5  * Copyright (c) 2012 David Herrmann <dh.herrmann@googlemail.com>
   6  *
   7  * Permission is hereby granted, free of charge, to any person obtaining
   8  * a copy of this software and associated documentation files
   9  * (the "Software"), to deal in the Software without restriction, including
  10  * without limitation the rights to use, copy, modify, merge, publish,
  11  * distribute, sublicense, and/or sell copies of the Software, and to
  12  * permit persons to whom the Software is furnished to do so, subject to
  13  * the following conditions:
  14  *
  15  * The above copyright notice and this permission notice shall be included
  16  * in all copies or substantial portions of the Software.
  17  *
  18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  19  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  20  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
  21  * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
  22  * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
  23  * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
  24  * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  25  */
  26
  27 #include <errno.h>
  28 #include <inttypes.h>
  29 #include <linux/input.h>
  30 #include <stdbool.h>
  31 #include <stdlib.h>
  32 #include <string.h>
  33 #include <xkbcommon/xkbcommon.h>
  34 #include "log.h"
  35 #include "shl_misc.h"
  36 #include "uterm.h"
  37 #include "uterm_input.h"
  38
  39 #define LOG_SUBSYSTEM "input_uxkb"
  40
  41 int uxkb_desc_init(struct uterm_input *input,
  42                    const char *layout,
  43                    const char *variant,
  44                    const char *options)
  45 {
  46         int ret;
  47         struct xkb_rule_names rmlvo = {
  48                 .rules = "evdev",
  49                 .model = "evdev",
  50                 .layout = layout,
  51                 .variant = variant,
  52                 .options = options,
  53         };
  54
  55         input->ctx = xkb_context_new(0);
  56         if (!input->ctx) {
  57                 log_error("cannot create XKB context");
  58                 return -ENOMEM;
  59         }
  60
  61         input->keymap = xkb_map_new_from_names(input->ctx, &rmlvo, 0);
  62         if (!input->keymap) {
  63                 log_warn("failed to create keymap (%s, %s, %s), "
  64                          "reverting to default US keymap",
  65                          layout, variant, options);
  66
  67                 rmlvo.layout = "us";
  68                 rmlvo.variant = "";
  69                 rmlvo.options = "";
  70
  71                 input->keymap = xkb_map_new_from_names(input->ctx, &rmlvo, 0);
  72                 if (!input->keymap) {
  73                         log_warn("failed to create XKB keymap");
  74                         ret = -EFAULT;
  75                         goto err_ctx;
  76                 }
  77         }
  78
  79         log_debug("new keyboard description (%s, %s, %s)",
  80                   layout, variant, options);
  81         return 0;
  82
  83 err_ctx:
  84         xkb_context_unref(input->ctx);
  85         return ret;
  86 }
  87
  88 void uxkb_desc_destroy(struct uterm_input *input)
  89 {
  90         xkb_map_unref(input->keymap);
  91         xkb_context_unref(input->ctx);
  92 }
  93
  94 int uxkb_dev_init(struct uterm_input_dev *dev)
  95 {
  96         dev->state = xkb_state_new(dev->input->keymap);
  97         if (!dev->state)
  98                 return -ENOMEM;
  99
 100         return 0;
 101 }
 102
 103 void uxkb_dev_destroy(struct uterm_input_dev *dev)
 104 {
 105         xkb_state_unref(dev->state);
 106 }
 107
 108 #define EVDEV_KEYCODE_OFFSET 8
 109 enum {
 110         KEY_RELEASED = 0,
 111         KEY_PRESSED = 1,
 112         KEY_REPEATED = 2,
 113 };
 114
 115 int uxkb_dev_process(struct uterm_input_dev *dev,
 116                      uint16_t key_state, uint16_t code)
 117 {
 118         struct xkb_state *state;
 119         struct xkb_keymap *keymap;
 120         xkb_keycode_t keycode;
 121         const xkb_keysym_t *keysyms;
 122         int num_keysyms, i;
 123         uint32_t *tmp;
 124
 125         state = dev->state;
 126         keymap = xkb_state_get_map(state);
 127         keycode = code + EVDEV_KEYCODE_OFFSET;
 128
 129         num_keysyms = xkb_key_get_syms(state, keycode, &keysyms);
 130
 131         if (key_state == KEY_PRESSED)
 132                 xkb_state_update_key(state, keycode, XKB_KEY_DOWN);
 133         else if (key_state == KEY_RELEASED)
 134                 xkb_state_update_key(state, keycode, XKB_KEY_UP);
 135
 136         if (key_state == KEY_RELEASED)
 137                 return -ENOKEY;
 138
 139         if (key_state == KEY_REPEATED && !xkb_key_repeats(keymap, keycode))
 140                 return -ENOKEY;
 141
 142         if (num_keysyms <= 0)
 143                 return -ENOKEY;
 144
 145         if (dev->num_syms < num_keysyms) {
 146                 tmp = realloc(dev->event.keysyms,
 147                               sizeof(uint32_t) * num_keysyms);
 148                 if (!tmp) {
 149                         log_warning("cannot reallocate keysym buffer");
 150                         return -ENOKEY;
 151                 }
 152                 dev->event.keysyms = tmp;
 153
 154                 tmp = realloc(dev->event.codepoints,
 155                               sizeof(uint32_t) * num_keysyms);
 156                 if (!tmp) {
 157                         log_warning("cannot reallocate codepoints buffer");
 158                         return -ENOKEY;
 159                 }
 160                 dev->event.codepoints = tmp;
 161
 162                 dev->num_syms = num_keysyms;
 163         }
 164
 165         dev->event.handled = false;
 166         dev->event.keycode = code;
 167         dev->event.ascii = shl_get_ascii(state, code, keysyms, num_keysyms);
 168         dev->event.mods = shl_get_xkb_mods(state);
 169         dev->event.num_syms = num_keysyms;
 170         memcpy(dev->event.keysyms, keysyms, sizeof(uint32_t) * num_keysyms);
 171
 172         for (i = 0; i < num_keysyms; ++i) {
 173                 dev->event.codepoints[i] = xkb_keysym_to_utf32(keysyms[i]);
 174                 if (!dev->event.codepoints[i])
 175                         dev->event.codepoints[i] = UTERM_INPUT_INVALID;
 176         }
 177
 178         return 0;
 179 }
 180
 181 /*
 182  * Call this when we regain control of the keyboard after losing it.
 183  * We don't reset the locked group, this should survive a VT switch, etc. The
 184  * locked modifiers are reset according to the keyboard LEDs.
 185  */
 186 void uxkb_dev_reset(struct uterm_input_dev *dev, const unsigned long *ledbits)
 187 {
 188         unsigned int i;
 189         struct xkb_state *state;
 190         static const struct {
 191                 int led;
 192                 const char *name;
 193         } led_names[] = {
 194                 { LED_NUML, XKB_LED_NAME_NUM },
 195                 { LED_CAPSL, XKB_LED_NAME_CAPS },
 196                 { LED_SCROLLL, XKB_LED_NAME_SCROLL },
 197         };
 198
 199         /* TODO: Urghs, while the input device was closed we might have missed
 200          * some events that affect internal state. As xkbcommon does not provide
 201          * a way to reset the internal state, we simply recreate the state. This
 202          * should have the same effect.
 203          * It also has a bug that if the CTRL-Release event is skipped, then
 204          * every further release will never perform a _real_ release. Kind of
 205          * buggy so we should fix it upstream. */
 206         state = xkb_state_new(dev->input->keymap);
 207         if (!state) {
 208                 log_warning("cannot recreate xkb-state");
 209                 return;
 210         }
 211         xkb_state_unref(dev->state);
 212         dev->state = state;
 213
 214         for (i = 0; i < sizeof(led_names) / sizeof(*led_names); i++) {
 215                 if (!input_bit_is_set(ledbits, led_names[i].led))
 216                         continue;
 217
 218                 /*
 219                  * TODO: Add support in xkbcommon for setting the led state,
 220                  * and updating the modifier state accordingly. E.g., something
 221                  * like this:
 222                  *      xkb_state_led_name_set_active(state, led_names[i].led);
 223                  */
 224         }
 225 }