keygrabber.c

   1 /*
   2  * keygrabber.c - key grabbing
   3  *
   4  * Copyright © 2008 Julien Danjou <julien@danjou.info>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License along
  17  * with this program; if not, write to the Free Software Foundation, Inc.,
  18  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  19  *
  20  */
  21
  22 #include <unistd.h>
  23
  24 #include "globalconf.h"
  25 #include "keygrabber.h"
  26 #include "key.h"
  27 #include "luaa.h"
  28 #include "common/xutil.h"
  29
  30 /** Grab the keyboard.
  31  * \return True if keyboard was grabbed.
  32  */
  33 static bool
  34 keygrabber_grab(void)
  35 {
  36     int i;
  37     xcb_grab_keyboard_reply_t *xgb;
  38
  39     for(i = 1000; i; i--)
  40     {
  41         if((xgb = xcb_grab_keyboard_reply(globalconf.connection,
  42                                           xcb_grab_keyboard(globalconf.connection, true,
  43                                                             xutil_screen_get(globalconf.connection,
  44                                                                                globalconf.default_screen)->root,
  45                                                             XCB_CURRENT_TIME, XCB_GRAB_MODE_ASYNC,
  46                                                             XCB_GRAB_MODE_ASYNC),
  47                                           NULL)))
  48         {
  49             p_delete(&xgb);
  50             return true;
  51         }
  52         usleep(1000);
  53     }
  54     return false;
  55 }
  56
  57 /** Handle keypress event.
  58  * \param L Lua stack to push the key pressed.
  59  * \param e Received XKeyEvent.
  60  * \return True if a key was successfully get, false otherwise.
  61  */
  62 bool
  63 keygrabber_handlekpress(lua_State *L, xcb_key_press_event_t *e)
  64 {
  65     /* transfer event (keycode + modifiers) to keysym */
  66     xcb_keysym_t ksym = key_getkeysym(e->detail, e->state);
  67
  68     /* convert keysym to string */
  69     char buf[MAX(MB_LEN_MAX, 32)];
  70     if(!key_press_lookup_string(ksym, buf, countof(buf)))
  71         return false;
  72
  73     luaA_pushmodifiers(L, e->state);
  74
  75     lua_pushstring(L, buf);
  76
  77     switch(e->response_type)
  78     {
  79       case XCB_KEY_PRESS:
  80         lua_pushliteral(L, "press");
  81         break;
  82       case XCB_KEY_RELEASE:
  83         lua_pushliteral(L, "release");
  84         break;
  85     }
  86
  87     return true;
  88 }
  89
  90 /** Grab keyboard and read pressed keys, calling callback function at each key
  91  * pressed. The callback function must return a boolean value: true to
  92  * continue grabbing, false to stop.
  93  * The function is called with 3 arguments:
  94  * a table containing modifiers keys, a string with the key pressed and a
  95  * string with either "press" or "release" to indicate the event type.
  96  *
  97  * \param L The Lua VM state.
  98  * \return The number of elements pushed on stack.
  99  *
 100  * \luastack
 101  *
 102  * \lparam A callback function as described above.
 103  */
 104 static int
 105 luaA_keygrabber_run(lua_State *L)
 106 {
 107     if(globalconf.keygrabber != LUA_REFNIL)
 108         luaL_error(L, "keygrabber already running");
 109
 110     luaA_registerfct(L, 1, &globalconf.keygrabber);
 111
 112     if(!keygrabber_grab())
 113     {
 114         luaA_unregister(L, &globalconf.keygrabber);
 115         luaL_error(L, "unable to grab keyboard");
 116     }
 117
 118     return 0;
 119 }
 120
 121 /** Stop grabbing the keyboard.
 122  * \param L The Lua VM state.
 123  * \return The number of elements pushed on stack.
 124  */
 125 int
 126 luaA_keygrabber_stop(lua_State *L)
 127 {
 128     xcb_ungrab_keyboard(globalconf.connection, XCB_CURRENT_TIME);
 129     luaA_unregister(L, &globalconf.keygrabber);
 130     return 0;
 131 }
 132
 133 const struct luaL_reg awesome_keygrabber_lib[] =
 134 {
 135     { "run", luaA_keygrabber_run },
 136     { "stop", luaA_keygrabber_stop },
 137     { NULL, NULL }
 138 };
 139
 140 // vim: filetype=c:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:encoding=utf-8:textwidth=80