src/lua.c

   1 /* Lua scripting support
   2  *
   3  * Copyright (c) 2008 Sadrul Habib Chowdhury (sadrul@users.sf.net)
   4  * Copyright (c) 2009
   5  *      Sadrul Habib Chowdhury (sadrul@users.sf.net)
   6  *      Rui Guo (firemeteor.guo@gmail.com)
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 3, or (at your option)
  11  * any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program (see the file COPYING); if not, write to the
  20  * Free Software Foundation, Inc.,
  21  * 51 Franklin Street, Fifth Floor, Boston, MA  02111-1301  USA
  22  *
  23  ****************************************************************
  24  */
  25 #include <sys/types.h>
  26 #include "config.h"
  27 #include "screen.h"
  28 #include <sys/stat.h>
  29 #include <unistd.h>
  30
  31 #include <stdio.h>
  32 #include <string.h>
  33 #include <stdlib.h>
  34
  35 #include "extern.h"
  36 #include "logfile.h"
  37
  38 #include <lua.h>
  39 #include <lauxlib.h>
  40 #include <lualib.h>
  41
  42 static int StackDump(lua_State *L, const char *message)
  43 {
  44   FILE *f = fopen("/tmp/debug/stack", "ab");
  45   int i = lua_gettop(L);
  46   if (message)
  47     fprintf(f, "%s", message);
  48   while (i)
  49     {
  50       int t = lua_type(L, i);
  51       switch (t)
  52         {
  53           case LUA_TSTRING:
  54             fprintf(f, "String: %s\n", lua_tostring(L, i));
  55             break;
  56
  57           case LUA_TBOOLEAN:
  58             fprintf(f, "Boolean: %s\n", lua_toboolean(L, i) ? "true" : "false");
  59             break;
  60
  61           case LUA_TNUMBER:
  62             fprintf(f, "Number: %g\n", lua_tonumber(L, i));
  63             break;
  64
  65           default:
  66             fprintf(f, "Type: %s\n", lua_typename(L, t));
  67         }
  68       i--;
  69     }
  70   if (message)
  71     fprintf(f, "----\n");
  72   fclose(f);
  73   return 0;
  74 }
  75
  76 extern struct win *windows, *fore;
  77 extern struct display *displays, *display;
  78 extern struct LayFuncs WinLf;
  79 extern struct layer *flayer;
  80 extern void AppendWinMsgRend(const char *str, const char *color);
  81 extern void FocusCanvas(struct canvas *cv);
  82
  83 static int LuaDispatch(void *handler, const char *params, va_list va);
  84 static int LuaRegEvent(lua_State *L);
  85 static void LuaShowErr(lua_State *L);
  86 struct binding lua_binding;
  87
  88 enum
  89 {
  90   LUA_HANDLER_TYPE_N = 1,
  91   LUA_HANDLER_TYPE_F
  92 };
  93
  94 struct lua_handler
  95 {
  96   int type;
  97   union
  98   {
  99     const char *name;
 100     int reference;
 101   } u;
 102 };
 103
 104 typedef struct lua_handler *lua_handler;
 105 void LuaPushHandler(lua_State *L, lua_handler lh);
 106 void LuaHUnRef(lua_State *L, int key);
 107 lua_handler LuaCheckHandler(lua_State *L, int idx, int ref);
 108
 109 lua_handler
 110 LuaAllocHandler(const char *name, int ref)
 111 {
 112   struct lua_handler *lh;
 113   lh = (struct lua_handler*) malloc(sizeof(struct lua_handler));
 114   if (!lh)
 115     return NULL;
 116
 117   if (name)
 118     {
 119       lh->type = LUA_HANDLER_TYPE_N;
 120       lh->u.name = SaveStr(name);
 121     }
 122   else
 123     {
 124       lh->type = LUA_HANDLER_TYPE_F;
 125       lh->u.reference = ref;
 126     }
 127
 128   return lh;
 129 }
 130
 131 void
 132 LuaFreeHandler(lua_State *L, struct lua_handler **lh)
 133 {
 134   if ((*lh)->type == LUA_HANDLER_TYPE_N)
 135     Free((*lh)->u.name)
 136   else
 137     {
 138       LuaHUnRef(L, (*lh)->u.reference);
 139       (*lh)->u.reference = 0;
 140     }
 141   Free(*lh);
 142 }
 143 /** Template {{{ */
 144
 145 #define CHECK_TYPE(name, type) \
 146 static type * \
 147 check_##name(lua_State *L, int index) \
 148 { \
 149   struct broker **broker; \
 150   type *var; \
 151   luaL_checktype(L, index, LUA_TUSERDATA); \
 152   broker = (struct broker **) luaL_checkudata(L, index, #name); \
 153   if (broker) { \
 154       var = (type *)get_broker_obj(broker); \
 155   } \
 156   if (!broker || !*broker) \
 157     luaL_typerror(L, index, #name); \
 158   return var; \
 159 }
 160
 161 #define PUSH_TYPE(name, type) \
 162 static void \
 163 push_##name(lua_State *L, type **t) \
 164 { \
 165   if (!t || !*t) \
 166     lua_pushnil(L); \
 167   else \
 168     { \
 169       struct broker **r; \
 170       r = (struct broker **)lua_newuserdata(L, sizeof(struct broker *)); \
 171       *r = get_obj_broker(*t); \
 172       luaL_getmetatable(L, #name); \
 173       lua_setmetatable(L,-2); \
 174     } \
 175 }
 176
 177 /* Much of the following template comes from:
 178  *      http://lua-users.org/wiki/BindingWithMembersAndMethods
 179  */
 180
 181 static int get_int (lua_State *L, void *v)
 182 {
 183   lua_pushinteger (L, *(int*)v);
 184   return 1;
 185 }
 186
 187 static int set_int (lua_State *L, void *v)
 188 {
 189   *(int*)v = luaL_checkint(L, 3);
 190   return 0;
 191 }
 192
 193 static int get_number (lua_State *L, void *v)
 194 {
 195   lua_pushnumber(L, *(lua_Number*)v);
 196   return 1;
 197 }
 198
 199 static int set_number (lua_State *L, void *v)
 200 {
 201   *(lua_Number*)v = luaL_checknumber(L, 3);
 202   return 0;
 203 }
 204
 205 static int get_string (lua_State *L, void *v)
 206 {
 207   lua_pushstring(L, (char*)v );
 208   return 1;
 209 }
 210
 211 static int set_string (lua_State *L, void *v)
 212 {
 213   *(const char**)v = luaL_checkstring(L, 3);
 214   return 0;
 215 }
 216
 217 typedef int (*Xet_func) (lua_State *L, void *v);
 218
 219 /* member info for get and set handlers */
 220 struct Xet_reg
 221 {
 222   const char *name;  /* member name */
 223   Xet_func func;     /* get or set function for type of member */
 224   size_t offset;     /* offset of member within the struct */
 225   int (*absolute)(lua_State *);
 226 };
 227
 228 static void Xet_add (lua_State *L, const struct Xet_reg *l)
 229 {
 230   if (!l)
 231     return;
 232   for (; l->name; l++)
 233     {
 234       lua_pushstring(L, l->name);
 235       lua_pushlightuserdata(L, (void*)l);
 236       lua_settable(L, -3);
 237     }
 238 }
 239
 240 static int Xet_call (lua_State *L)
 241 {
 242   /* for get: stack has userdata, index, lightuserdata */
 243   /* for set: stack has userdata, index, value, lightuserdata */
 244   const struct Xet_reg *m = (const struct Xet_reg *)lua_touserdata(L, -1);  /* member info */
 245   void *obj;
 246   lua_pop(L, 1);                               /* drop lightuserdata */
 247   luaL_checktype(L, 1, LUA_TUSERDATA);
 248   if (m->absolute)
 249     return m->absolute(L);
 250   obj = get_broker_obj((struct broker **)lua_touserdata(L, 1));
 251   return m->func(L, (char *)obj + m->offset);
 252 }
 253
 254 static int index_handler (lua_State *L)
 255 {
 256   /* stack has userdata, index */
 257   lua_pushvalue(L, 2);                     /* dup index */
 258   lua_rawget(L, lua_upvalueindex(1));      /* lookup member by name */
 259   if (!lua_islightuserdata(L, -1))
 260     {
 261       lua_pop(L, 1);                         /* drop value */
 262       lua_pushvalue(L, 2);                   /* dup index */
 263       lua_gettable(L, lua_upvalueindex(2));  /* else try methods */
 264       if (lua_isnil(L, -1))                  /* invalid member */
 265         luaL_error(L, "cannot get member '%s'", lua_tostring(L, 2));
 266       return 1;
 267     }
 268   return Xet_call(L);                      /* call get function */
 269 }
 270
 271 static int newindex_handler (lua_State *L)
 272 {
 273   /* stack has userdata, index, value */
 274   lua_pushvalue(L, 2);                     /* dup index */
 275   lua_rawget(L, lua_upvalueindex(1));      /* lookup member by name */
 276   if (!lua_islightuserdata(L, -1))         /* invalid member */
 277     luaL_error(L, "cannot set member '%s'", lua_tostring(L, 2));
 278   return Xet_call(L);                      /* call set function */
 279 }
 280
 281 static int
 282 struct_register(lua_State *L, const char *name, const luaL_reg fn_methods[], const luaL_reg meta_methods[],
 283     const struct Xet_reg setters[], const struct Xet_reg getters[])
 284 {
 285   int metatable, methods;
 286
 287   /* create methods table & add it to the table of globals */
 288   luaL_register(L, name, fn_methods);
 289   methods = lua_gettop(L);
 290
 291   /* create metatable & add it to the registry */
 292   luaL_newmetatable(L, name);
 293   luaL_register(L, 0, meta_methods);  /* fill metatable */
 294
 295   /* To identify the type of object */
 296   lua_pushstring(L, "_objname");
 297   lua_pushstring(L, name);
 298   lua_rawset(L, -3);
 299
 300   metatable = lua_gettop(L);
 301
 302   lua_pushliteral(L, "__metatable");
 303   lua_pushvalue(L, methods);    /* dup methods table*/
 304   lua_rawset(L, metatable);     /* hide metatable:
 305                                    metatable.__metatable = methods */
 306
 307   lua_pushliteral(L, "__index");
 308   lua_pushvalue(L, metatable);  /* upvalue index 1 */
 309   Xet_add(L, getters);     /* fill metatable with getters */
 310   lua_pushvalue(L, methods);    /* upvalue index 2 */
 311   lua_pushcclosure(L, index_handler, 2);
 312   lua_rawset(L, metatable);     /* metatable.__index = index_handler */
 313
 314   lua_pushliteral(L, "__newindex");
 315   lua_newtable(L);              /* table for members you can set */
 316   Xet_add(L, setters);     /* fill with setters */
 317   lua_pushcclosure(L, newindex_handler, 1);
 318   lua_rawset(L, metatable);     /* metatable.__newindex = newindex_handler */
 319
 320   /* FIXME: Why do we leave an element on the stack? */
 321   lua_pop(L, 1);                /* drop metatable */
 322   return 1;                     /* return methods on the stack */
 323 }
 324
 325 /** }}} */
 326
 327 /** Callback {{{ */
 328 static void
 329 push_callback(lua_State *L, struct listener **t)
 330 {
 331   if (!t || !*t)
 332     lua_pushnil(L);
 333   else
 334     {
 335       struct listener **r;
 336       r = (struct listener **)lua_newuserdata(L, sizeof(struct listener *));
 337       *r = *t;
 338       luaL_getmetatable(L, "callback");
 339       lua_setmetatable(L,-2);
 340     }
 341 }
 342
 343
 344 static int
 345 internal_unhook(lua_State *L, int warn)
 346 {
 347   /*Emulate check_callback() */
 348   struct listener **ppl;
 349   luaL_checktype(L, 1, LUA_TUSERDATA);
 350   ppl = (struct listener **) luaL_checkudata(L, 1, "callback");
 351
 352   if (!ppl)
 353     luaL_typerror(L, 1, "callback");
 354
 355   if (!*ppl)
 356     {
 357       if (warn)
 358         {
 359           lua_pushboolean(L, 0);
 360           lua_pushstring(L, "Callback already unhooked.");
 361           LuaShowErr(L);
 362         }
 363     }
 364   else
 365     {
 366       LuaFreeHandler(L, (lua_handler *)&(*ppl)->handler);
 367       unregister_listener(*ppl);
 368       *ppl = 0;
 369       if (warn)
 370         lua_pushboolean(L, 1);
 371     }
 372   return warn != 0;
 373 }
 374 static int
 375 callback_unhook(lua_State *L)
 376 {
 377   return internal_unhook(L, 1);
 378 }
 379
 380 static const luaL_reg callback_methods[] = {
 381   {"unhook", callback_unhook},
 382   {0, 0}
 383 };
 384
 385 int
 386 callback_collect(lua_State *L)
 387 {
 388   return internal_unhook(L, 0);
 389 }
 390
 391 static const luaL_reg callback_metamethods[] = {
 392   {"__gc", callback_collect},
 393   {0, 0}
 394 };
 395
 396 static const struct Xet_reg callback_setters[] = {
 397   {0, 0}
 398 };
 399
 400 static const struct Xet_reg callback_getters[] = {
 401   {0, 0}
 402 };
 403
 404
 405 /** }}} */
 406
 407 static int
 408 screen_object_collect(lua_State *L)
 409 {
 410   struct broker **pbroker;
 411   luaL_checktype(L, 1, LUA_TUSERDATA);
 412   pbroker = (struct broker **)lua_touserdata(L, 1);
 413   broker_unref(pbroker);
 414   return 0;
 415 }
 416
 417 /** Window {{{ */
 418
 419 PUSH_TYPE(window, struct win)
 420
 421 CHECK_TYPE(window, struct win)
 422
 423 static int get_window(lua_State *L, void *v)
 424 {
 425   push_window(L, (struct win **)v);
 426   return 1;
 427 }
 428
 429 static int
 430 window_change_title(lua_State *L)
 431 {
 432   struct win *w = check_window(L, 1);
 433   unsigned int len;
 434   const char *title = luaL_checklstring(L, 3, &len);
 435   ChangeAKA(w, (char *)title, len);
 436   return 0;
 437 }
 438
 439 static int
 440 window_change_number(lua_State *L)
 441 {
 442   struct win *w = check_window(L, 1);
 443   int newnum = luaL_checkint(L, 3);
 444   ChangeWinNum(w->w_number, newnum);
 445   return 0;
 446 }
 447
 448 static int
 449 window_get_monitor_status(lua_State *L)
 450 {
 451   struct win *w = check_window(L, 1);
 452   int activity = luaL_checkint(L, 2);
 453   if (activity)
 454     /*monitor*/
 455     lua_pushinteger(L, w->w_monitor != MON_OFF);
 456   else
 457     /*silence*/
 458     lua_pushinteger(L, w->w_silence == SILENCE_ON ? w->w_silencewait: 0);
 459
 460   return 1;
 461 }
 462
 463 static int
 464 window_stuff(lua_State *L)
 465 {
 466   unsigned int len;
 467   struct layer *oldflayer = flayer;
 468   struct win *w = check_window(L, 1);
 469   const char *str = luaL_checklstring(L, 2, &len);
 470
 471   flayer = &w->w_layer;
 472   while(len)
 473     LayProcess((char **)&str, (int *) &len);
 474   flayer = oldflayer;
 475   return 0;
 476 }
 477
 478 static int
 479 window_activate(lua_State *L)
 480 {
 481   struct win *w = check_window(L, 1);
 482   SetForeWindow(w);
 483   return 0;
 484 }
 485
 486 static int
 487 window_get_showing_canvases(lua_State *L)
 488 {
 489   struct win *w = check_window(L, 1);
 490   int count = 0;
 491   struct canvas *cv = w->w_layer.l_cvlist;
 492   if (!cv) {
 493       lua_pushnil(L);
 494       return 1;
 495   }
 496   lua_newtable(L);
 497   while (cv) {
 498     lua_pushinteger(L, count++);
 499     push_canvas(L, &cv);
 500     lua_settable(L, -3);
 501     cv = cv->c_lnext;
 502   }
 503
 504   return 1;
 505 }
 506
 507 static const luaL_reg window_methods[] = {
 508   {"get_monitor_status", window_get_monitor_status},
 509   {"showing_canvases", window_get_showing_canvases},
 510   {"stuff", window_stuff},
 511   {"activate", window_activate},
 512   {"hook", LuaRegEvent},
 513   {0, 0}
 514 };
 515
 516 static int
 517 window_tostring(lua_State *L)
 518 {
 519   char str[128];
 520   struct win *w = check_window(L, 1);
 521   snprintf(str, sizeof(str), "{window #%d: '%s'}", w->w_number, w->w_title);
 522   lua_pushstring(L, str);
 523   return 1;
 524 }
 525
 526 static int
 527 window_equality(lua_State *L)
 528 {
 529   struct win *w1 = check_window(L, 1), *w2 = check_window(L, 2);
 530   lua_pushboolean(L, (w1 == w2 || (w1 && w2 && w1->w_number == w2->w_number)));
 531   return 1;
 532 }
 533
 534 static const luaL_reg window_metamethods[] = {
 535   {"__tostring", window_tostring},
 536   {"__eq", window_equality},
 537   {"__gc", screen_object_collect},
 538   {0, 0}
 539 };
 540
 541 static const struct Xet_reg window_setters[] = {
 542   {"title", 0, 0, window_change_title/*absolute setter*/},
 543   {"number", 0, 0, window_change_number/*absolute setter*/},
 544   {0, 0}
 545 };
 546
 547 static const struct Xet_reg window_getters[] = {
 548   {"title", get_string, offsetof(struct win, w_title) + 8},
 549   {"number", get_int, offsetof(struct win, w_number)},
 550   {"dir", get_string, offsetof(struct win, w_dir)},
 551   {"tty", get_string, offsetof(struct win, w_tty)},
 552   {"pid", get_int, offsetof(struct win, w_pid)},
 553   {"group", get_window, offsetof(struct win, w_group)},
 554   {"bell", get_int, offsetof(struct win, w_bell)},
 555   {0, 0}
 556 };
 557
 558
 559 /** }}} */
 560
 561 /** AclUser {{{ */
 562
 563 PUSH_TYPE(user, struct acluser)
 564
 565 CHECK_TYPE(user, struct acluser)
 566
 567 static int
 568 get_user(lua_State *L, void *v)
 569 {
 570   push_user(L, (struct acluser **)v);
 571   return 1;
 572 }
 573
 574 static const luaL_reg user_methods[] = {
 575   {0, 0}
 576 };
 577
 578 static int
 579 user_tostring(lua_State *L)
 580 {
 581   char str[128];
 582   struct acluser *u = check_user(L, 1);
 583   snprintf(str, sizeof(str), "{user '%s'}", u->u_name);
 584   lua_pushstring(L, str);
 585   return 1;
 586 }
 587
 588 static const luaL_reg user_metamethods[] = {
 589   {"__tostring", user_tostring},
 590   {"__gc", screen_object_collect},
 591   {0, 0}
 592 };
 593
 594 static const struct Xet_reg user_setters[] = {
 595   {0, 0}
 596 };
 597
 598 static const struct Xet_reg user_getters[] = {
 599   {"name", get_string, offsetof(struct acluser, u_name)},
 600   {"password", get_string, offsetof(struct acluser, u_password)},
 601   {0, 0}
 602 };
 603
 604 /** }}} */
 605
 606 static int get_display(lua_State *L, void *v);
 607 /** Canvas {{{ */
 608
 609 PUSH_TYPE(canvas, struct canvas)
 610
 611 CHECK_TYPE(canvas, struct canvas)
 612
 613 static int
 614 get_canvas(lua_State *L, void *v)
 615 {
 616   push_canvas(L, (struct canvas **)v);
 617   return 1;
 618 }
 619
 620 static int
 621 canvas_select(lua_State *L)
 622 {
 623   struct canvas *c = check_canvas(L, 1);
 624   if (!display || D_forecv == c)
 625     return 0;
 626   /* FIXME: why do we need this? */
 627   SetCanvasWindow(c, Layer2Window(c->c_layer));
 628
 629   FocusCanvas(c);
 630   return 0;
 631 }
 632
 633 static int
 634 canvas_split(lua_State *L)
 635 {
 636   struct canvas *c = check_canvas(L, 1);
 637   int hori = lua_toboolean(L, 2);
 638   if (hori)
 639     AddCanvas(SLICE_HORI);
 640   else
 641     AddCanvas(SLICE_VERT);
 642   Activate(-1);
 643   return 0;
 644 }
 645
 646 static int
 647 canvas_showwin(lua_State *L)
 648 {
 649   struct canvas *c = check_canvas(L, 1);
 650   if (lua_isnil(L, 2))
 651     SetCanvasWindow(c, 0);
 652   else
 653     {
 654       struct win *w = check_window(L, 2);
 655       SetCanvasWindow(c, w);
 656     }
 657   return 0;
 658 }
 659
 660 static const luaL_reg canvas_methods[] = {
 661   {"select", canvas_select},
 662   {"split", canvas_split},
 663   {"showwin", canvas_showwin},
 664   {0, 0}
 665 };
 666
 667 static const luaL_reg canvas_metamethods[] = {
 668   {"__gc", screen_object_collect},
 669   {0, 0}
 670 };
 671
 672 extern struct mchar mchar_so;
 673 static int
 674 canvas_update_caption(lua_State *L)
 675 {
 676   struct canvas *cv = check_canvas(L, 1);
 677   unsigned int len;
 678   const char *caption = luaL_checklstring(L, 3, &len);
 679   int l, padlen;
 680   padlen = cv->c_xe - cv->c_xs +
 681     (display ? (cv->c_xe + 1 < D_width || D_CLP): 0);
 682   struct win *w = Layer2Window(cv->c_layer);
 683   char * buf = MakeWinMsgEv((char *)caption, w, '%', padlen, &cv->c_captev, 0);
 684   if (cv->c_captev.timeout.tv_sec)
 685     evenq(&cv->c_captev);
 686   l = strlen(buf);
 687
 688   GotoPos(cv->c_xs, cv->c_ye+1);
 689   /*XXX:what does this mean?*/
 690   SetRendition(&mchar_so);
 691   if (l > cv->c_xe - cv->c_xs + 1)
 692     l = cv->c_xe - cv->c_xs + 1;
 693   PutWinMsg(buf, cv->c_xs, l);
 694   l += cv->c_xs;
 695   for (; l <= cv->c_xe; l++)
 696     PUTCHARLP(' ');
 697
 698   return 0;
 699 }
 700
 701 static const struct Xet_reg canvas_setters[] = {
 702   {"caption", 0, 0, canvas_update_caption/*absolute setter*/},
 703   {0, 0}
 704 };
 705
 706 static int
 707 canvas_get_window(lua_State *L)
 708 {
 709   struct canvas *c = check_canvas(L, 1);
 710   struct win *win = Layer2Window(c->c_layer);
 711   if (win)
 712     push_window(L, &win);
 713   else
 714     lua_pushnil(L);
 715   return 1;
 716 }
 717
 718 static const struct Xet_reg canvas_getters[] = {
 719   {"next", get_canvas, offsetof(struct canvas, c_next)},
 720   {"xoff", get_int, offsetof(struct canvas, c_xoff)},
 721   {"yoff", get_int, offsetof(struct canvas, c_yoff)},
 722   {"xs", get_int, offsetof(struct canvas, c_xs)},
 723   {"ys", get_int, offsetof(struct canvas, c_ys)},
 724   {"xe", get_int, offsetof(struct canvas, c_xe)},
 725   {"ye", get_int, offsetof(struct canvas, c_ye)},
 726   {"window", 0, 0, canvas_get_window},
 727   {"display", get_display, offsetof(struct canvas, c_display)},
 728   {0, 0}
 729 };
 730
 731 /** }}} */
 732
 733 /** Layout {{{ */
 734
 735 PUSH_TYPE(layout, struct layout)
 736 CHECK_TYPE(layout, struct layout)
 737
 738 static const struct Xet_reg layout_getters[] = {
 739   {"title", get_string, offsetof(struct layout, lay_title)},
 740   {"number", get_string, offsetof(struct layout, lay_title)},
 741   {"autosave", get_string, offsetof(struct layout, lay_autosave)},
 742   {0,0}
 743 };
 744
 745 int
 746 layout_change_title(lua_State *L)
 747 {
 748   struct layout *lay = check_layout(L, 1);
 749   unsigned int len;
 750   const char *title = luaL_checklstring(L, 3, &len);
 751   free(lay->lay_title);
 752   lay->lay_title= SaveStr(title);
 753   return 0;
 754 }
 755
 756 void LayoutChangeNumber(struct layout *lay, int newnum);
 757
 758 int
 759 layout_change_number(lua_State *L)
 760 {
 761   struct layout *lay = check_layout(L, 1);
 762   int newnum = luaL_checkint(L, 3);
 763   LayoutChangeNumber(lay, newnum);
 764   return 0;
 765 }
 766
 767 static const struct Xet_reg layout_setters[] = {
 768   {"title", 0, 0, layout_change_title/*absolute setter*/},
 769   {"number", 0, 0, layout_change_number/*absolute setter*/},
 770   {"autosave", get_string, offsetof(struct layout, lay_autosave)},
 771   {0, 0}
 772 };
 773
 774 int
 775 layout_select(lua_State *L)
 776 {
 777   struct layout *lay = check_layout(L, 1);
 778   if (!display) return 0;
 779   LoadLayout(lay, &D_canvas);
 780   Activate(0);
 781   return 0;
 782 }
 783
 784 static const luaL_reg layout_methods[] = {
 785   {"select", layout_select},
 786   {0, 0}
 787 };
 788
 789 static const luaL_reg layout_metamethods[] = {
 790   {"__gc", screen_object_collect},
 791   {0, 0}
 792 };
 793
 794 static int
 795 get_layout(lua_State *L, void *v)
 796 {
 797   push_layout(L, (struct layout **)v);
 798   return 1;
 799 }
 800
 801 /** }}} */
 802
 803 /** Display {{{ */
 804
 805 PUSH_TYPE(display, struct display)
 806
 807 CHECK_TYPE(display, struct display)
 808
 809 static int
 810 get_display(lua_State *L, void *v)
 811 {
 812   push_display(L, (struct display **)v);
 813   return 1;
 814 }
 815
 816 static int
 817 display_get_canvases(lua_State *L)
 818 {
 819   struct display *d;
 820   struct canvas *iter;
 821   int count;
 822
 823   d = check_display(L, 1);
 824   lua_newtable(L);
 825   for (iter = d->d_cvlist, count = 0; iter; iter = iter->c_next, count++) {
 826     lua_pushinteger(L, count);
 827     push_canvas(L, &iter);
 828     lua_settable(L, -3);
 829   }
 830
 831   return 1;
 832 }
 833
 834 static int
 835 display_top_canvas(lua_State *L)
 836 {
 837   struct display *d;
 838   d = check_display(L, 1);
 839   push_canvas(L, &d->d_cvlist);
 840
 841   return 1;
 842 }
 843
 844 static int
 845 display_bot_canvas(lua_State *L)
 846 {
 847   struct display *d;
 848   struct canvas *c;
 849   d = check_display(L, 1);
 850
 851   for (c = d->d_cvlist; c->c_next; c = c->c_next)
 852     ;
 853   push_canvas(L, &c);
 854
 855   return 1;
 856 }
 857
 858 static const luaL_reg display_methods[] = {
 859   {"get_canvases", display_get_canvases},
 860   {"top_canvas", display_top_canvas},
 861   {"bottom_canvas", display_bot_canvas},
 862   {0, 0}
 863 };
 864
 865 static int
 866 display_tostring(lua_State *L)
 867 {
 868   char str[128];
 869   struct display *d = check_display(L, 1);
 870   snprintf(str, sizeof(str), "{display: tty = '%s', term = '%s'}", d->d_usertty, d->d_termname);
 871   lua_pushstring(L, str);
 872   return 1;
 873 }
 874
 875 static const luaL_reg display_metamethods[] = {
 876   {"__tostring", display_tostring},
 877   {"__gc", screen_object_collect},
 878   {0, 0}
 879 };
 880
 881 static int
 882 display_new_idle_timeout(lua_State *L)
 883 {
 884   struct display *disp = check_display(L, 1);
 885   int timeout = luaL_checkinteger(L, 3) * 1000;
 886   struct event *ev = &disp->d_idleev;
 887   if (timeout > 0)
 888     {
 889       SetTimeout(ev, timeout);
 890       if (!ev->queued)
 891         evenq(ev);
 892     }
 893   else
 894     evdeq(ev);
 895
 896   return 0;
 897 }
 898
 899 static const struct Xet_reg display_setters[] = {
 900   {"idle_timeout", 0, 0, display_new_idle_timeout/*absolute setter*/},
 901   {0, 0}
 902 };
 903
 904 static const struct Xet_reg display_getters[] = {
 905   {"tty", get_string, offsetof(struct display, d_usertty)},
 906   {"term", get_string, offsetof(struct display, d_termname)},
 907   {"fore", get_window, offsetof(struct display, d_fore)},
 908   {"other", get_window, offsetof(struct display, d_other)},
 909   {"width", get_int, offsetof(struct display, d_width)},
 910   {"height", get_int, offsetof(struct display, d_height)},
 911   {"user", get_user, offsetof(struct display, d_user)},
 912   {"layout", get_layout, offsetof(struct display, d_layout)},
 913   {0, 0}
 914 };
 915
 916 /** }}} */
 917
 918 /** Screen {{{ */
 919
 920 static int
 921 screen_get_windows(lua_State *L)
 922 {
 923   struct win *iter;
 924   int count;
 925
 926   lua_newtable(L);
 927   for (iter = windows, count = 0; iter; iter = iter->w_next, count++) {
 928     lua_pushinteger(L, iter->w_number);
 929     push_window(L, &iter);
 930     lua_settable(L, -3);
 931   }
 932
 933   return 1;
 934 }
 935
 936 static int
 937 screen_get_displays(lua_State *L)
 938 {
 939   struct display *iter;
 940   int count;
 941
 942   lua_newtable(L);
 943   for (iter = displays, count = 0; iter; iter = iter->d_next, count++) {
 944     lua_pushinteger(L, count);
 945     push_display(L, &iter);
 946     lua_settable(L, -3);
 947   }
 948
 949   return 1;
 950 }
 951
 952 extern struct layout *layouts;
 953 static int
 954 screen_get_layouts(lua_State *L)
 955 {
 956   struct layout *iter;
 957   int count;
 958
 959   lua_newtable(L);
 960   for (iter = layouts, count = 0; iter; iter = iter->lay_next, count++) {
 961     lua_pushinteger(L, iter->lay_number);
 962     push_layout(L, &iter);
 963     lua_settable(L, -3);
 964   }
 965
 966   return 1;
 967 }
 968
 969 static int
 970 screen_get_display(lua_State *L)
 971 {
 972   push_display(L, &display);
 973   return 1;
 974 }
 975
 976 static int
 977 screen_exec_command(lua_State *L)
 978 {
 979   const char *command;
 980   unsigned int len;
 981
 982   command = luaL_checklstring(L, 1, &len);
 983   if (command)
 984     RcLine((char *)command, len);
 985
 986   return 0;
 987 }
 988
 989 static int
 990 screen_append_msg(lua_State *L)
 991 {
 992   const char *msg, *color;
 993   unsigned int len;
 994   msg = luaL_checklstring(L, 1, &len);
 995   if (lua_isnil(L, 2))
 996     color = NULL;
 997   else
 998     color = luaL_checklstring(L, 2, &len);
 999   AppendWinMsgRend(msg, color);
1000   return 0;
1001 }
1002
1003 struct sinput_data
1004 {
1005   lua_State *L;
1006   lua_handler lh;
1007 };
1008
1009 void
1010 script_input_fn(char *buf, int len, char *priv)
1011 {
1012   struct sinput_data *sidata = (struct sinput_data *)priv;
1013   lua_handler lh = sidata->lh;
1014   lua_State *L = sidata->L;
1015
1016   LuaPushHandler(L, lh);
1017   lua_pushstring(L, buf);
1018   if (lua_pcall(L, 1, 0, 0) == LUA_ERRRUN)
1019     {
1020       if(lua_isstring(L, -1))
1021         {
1022           LuaShowErr(L);
1023         }
1024     }
1025   free(sidata);
1026   LuaFreeHandler(L, &lh);
1027 }
1028
1029 static int
1030 screen_input(lua_State *L)
1031 {
1032   char *ss;
1033   int n;
1034   const char * prompt = NULL, *prefill = NULL;
1035   lua_handler lh;
1036   struct sinput_data *sidata;
1037
1038   prompt = luaL_checkstring(L, 1);
1039   lh = LuaCheckHandler(L, 2, 1);
1040   if (!lh)
1041     luaL_error(L, "Out of Memory");
1042
1043   if (lua_gettop(L) >= 3)
1044     prefill = luaL_checkstring(L, 3);
1045
1046
1047   sidata = (struct sinput_data *)malloc(sizeof(struct sinput_data));
1048   if (!sidata)
1049     {
1050       LuaFreeHandler(L, &lh);
1051       luaL_error(L, "Out of Memory");
1052     }
1053
1054   sidata->L = L;
1055   sidata->lh = lh;
1056   Input((char *)prompt, 100, INP_COOKED, script_input_fn, (char *)sidata, 0);
1057
1058   if (!prefill)
1059     return 0;
1060   for (; *prefill; prefill++)
1061     {
1062       if ((*(unsigned char *)prefill & 0x7f) < 0x20 || *prefill == 0x7f)
1063         continue;
1064       ss = (char *)prefill;
1065       n = 1;
1066       LayProcess(&ss, &n);
1067     }
1068   return 0;
1069 }
1070
1071 static void
1072 sev_schedule_fn(struct event *ev, char *data)
1073 {
1074   struct sinput_data *si = (struct sinput_data *)data;
1075   lua_handler lh = si->lh;
1076   lua_State *L = si->L;
1077   free(si);
1078   evdeq(ev);
1079   Free(ev);
1080
1081   LuaPushHandler(L, lh);
1082   if (lua_pcall(L, 1, 0, 0) == LUA_ERRRUN)
1083     {
1084       if(lua_isstring(L, -1))
1085         {
1086           LuaShowErr(L);
1087         }
1088     }
1089   LuaFreeHandler(L, &lh);
1090 }
1091
1092 static int
1093 screen_schedule(lua_State *L)
1094 {
1095   int timeout = luaL_checkinteger(L, 1);
1096   lua_handler lh = LuaCheckHandler(L, 2, 1);
1097   struct sinput_data *si;
1098   struct event *ev;
1099   if (timeout <= 0)
1100     return 0;
1101
1102   ev = (struct event *) calloc(1, sizeof(struct event));
1103   if (!ev)
1104     {
1105       LuaFreeHandler(L, &lh);
1106       luaL_error(L, "Out of Memory");
1107     }
1108   si = (struct sinput_data *) malloc(sizeof(struct sinput_data));
1109   if (!si)
1110     {
1111       LuaFreeHandler(L, &lh);
1112       Free(ev);
1113       luaL_error(L, "Out of Memory");
1114     }
1115   si->lh = lh;
1116   si->L = L;
1117
1118   ev->type = EV_TIMEOUT;
1119   ev->data = (char *)si;
1120   ev->handler = sev_schedule_fn;
1121   evenq(ev);
1122   SetTimeout(ev, timeout * 1000);
1123   return 0;
1124 }
1125
1126 static const luaL_reg screen_methods[] = {
1127   {"windows", screen_get_windows},
1128   {"displays", screen_get_displays},
1129   {"layouts", screen_get_layouts},
1130   {"display", screen_get_display},
1131   {"command", screen_exec_command},
1132   {"append_msg", screen_append_msg},
1133   {"hook", LuaRegEvent},
1134   {"input", screen_input},
1135   {"schedule", screen_schedule},
1136   {0, 0}
1137 };
1138
1139 static const luaL_reg screen_metamethods[] = {
1140   {0, 0}
1141 };
1142
1143 static const struct Xet_reg screen_setters[] = {
1144   {0, 0}
1145 };
1146
1147 static const struct Xet_reg screen_getters[] = {
1148   {0, 0}
1149 };
1150
1151 /** }}} */
1152
1153 /** Public functions {{{ */
1154
1155 /* FIXME: This code only tracks one unhook ticket for a lua func.
1156  * So it does not work if one func is registered more than one times. */
1157 static void
1158 prepare_weak_table(lua_State *L, const char *name, const char *mode)
1159 {
1160   luaL_getmetatable(L, "screen");
1161
1162   lua_pushstring(L, name);
1163   lua_newtable(L);
1164
1165   /* prepare a metatable to indicate weak table */
1166   lua_newtable(L);
1167   lua_pushstring(L, "__mode");
1168   lua_pushstring(L, mode);
1169   lua_rawset(L, -3);
1170   /* Mark weak table */
1171   lua_setmetatable(L, -2);
1172   lua_rawset(L, -3);
1173   lua_pop(L, 1);
1174 }
1175
1176 static lua_State *L;
1177 int LuaInit(void)
1178 {
1179   L = luaL_newstate();
1180
1181   luaL_openlibs(L);
1182
1183 #define REGISTER(X) struct_register(L, #X , X ## _methods, X##_metamethods, X##_setters, X##_getters)
1184
1185   REGISTER(screen);
1186   REGISTER(window);
1187   REGISTER(display);
1188   REGISTER(user);
1189   REGISTER(canvas);
1190   REGISTER(callback);
1191
1192   /* To store handler funcs */
1193
1194   /*_two kinds of information are mantained:
1195    *
1196    * funcreg[key]->func
1197    * The 'func' part of the tables are weak. That means the registered funcs
1198    * will be collected once the func is no longer available (e.g. overwritten
1199    * by a new instance of the script)
1200    *
1201    * To make this process happens faster, GC is forced at the end of each
1202    * source.
1203    * TODO: What if some events are triggered within the sourcing
1204    * procedure?
1205    * */
1206   prepare_weak_table(L, "_funcreg", "v");
1207
1208   /* funcunhook[func]->listener
1209    * The listener is the unhook ticket of the hook. which should be collected
1210    * once the func is collected. The gc metamethod will be triggered
1211    * accordingly. */
1212   prepare_weak_table(L, "_funcunhook", "k");
1213
1214   return 0;
1215 }
1216
1217 /* An error message on top of the stack. */
1218 static void
1219 LuaShowErr(lua_State *L)
1220 {
1221   struct display *d = display;
1222   unsigned int len;
1223   const char *message = luaL_checklstring(L, -1, &len);
1224   lua_pop(L, 1);
1225   LMsg(0, "%s", message ? message : "Unknown error");
1226   display = d;
1227 }
1228
1229 struct fn_def
1230 {
1231   void (*push_fn)(lua_State *, void*);
1232   void *value;
1233 };
1234
1235 static int
1236 LuaCallProcess(const char *name, struct fn_def defs[])
1237 {
1238   int argc = 0;
1239
1240   lua_getfield(L, LUA_GLOBALSINDEX, name);
1241   if (lua_isnil(L, -1))
1242     {
1243       lua_pop(L,1);
1244       return 0;
1245     }
1246   for (argc = 0; defs[argc].push_fn; argc++)
1247     defs[argc].push_fn(L, defs[argc].value);
1248   if (lua_pcall(L, argc, 0, 0) == LUA_ERRRUN && lua_isstring(L, -1))
1249     {
1250       LuaShowErr(L);
1251       return 0;
1252     }
1253   return 1;
1254 }
1255
1256 /* FIXME: Think about this: will it affect the registered handlers?*/
1257 int LuaSource(const char *file, int async)
1258 {
1259   if (!L)
1260     return 0;
1261   struct stat st;
1262   if (stat(file, &st) == -1)
1263     Msg(errno, "Error loading lua script file '%s'", file);
1264   else
1265     {
1266       int len = strlen(file);
1267       if (len < 4 || strncmp(file + len - 4, ".lua", 4) != 0)
1268         return 0;
1269       if (luaL_dofile(L, file) && lua_isstring(L, -1))
1270         {
1271           LuaShowErr(L);
1272           return 0;
1273         }
1274       else
1275         {
1276           /* It seems that I need two GC passes to really collect the unhook
1277            * ticket, after changing the reference to ticket in the
1278            * 'funcunhook' table from weak to strong. This should not be
1279            * harmful, but how can I make sure that two passes is enough?
1280            *
1281            * Possible reason:
1282            * This seems reasonable, since the first pass will collect the func
1283            * itself and make the ticket garbage, and the second pass will
1284            * collect the ticket itself.
1285            *
1286            * TODO: check this out. maybe ask some lua gurus. */
1287           lua_gc(L, LUA_GCCOLLECT, 0);
1288           lua_gc(L, LUA_GCCOLLECT, 0);
1289         }
1290       return 1;
1291     }
1292   return 0;
1293 }
1294
1295 int LuaFinit(void)
1296 {
1297   if (!L)
1298     return 0;
1299   lua_close(L);
1300   L = (lua_State*)0;
1301   return 0;
1302 }
1303
1304 static void
1305 push_stringarray(lua_State *L, char **args)
1306 {
1307   int i;
1308   lua_newtable(L);
1309   for (i = 1; args && *args; i++) {
1310     lua_pushinteger(L, i);
1311     lua_pushstring(L, *args++);
1312     lua_settable(L, -3);
1313   }
1314 }
1315
1316 int
1317 LuaPushParams(lua_State *L, const char *params, va_list va)
1318 {
1319   int num = 0;
1320   while (*params)
1321     {
1322       switch (*params)
1323         {
1324         case 's':
1325           lua_pushstring(L, va_arg(va, char *));
1326           break;
1327         case 'S':
1328           push_stringarray(L, va_arg(va, char **));
1329           break;
1330         case 'i':
1331           lua_pushinteger(L, va_arg(va, int));
1332           break;
1333         case 'd':
1334           {
1335             struct display *d = va_arg(va, struct display *);
1336             push_display(L, &d);
1337             break;
1338           }
1339         case 'w':
1340           {
1341             struct win *w = va_arg(va, struct win *);
1342             push_window(L, &w);
1343             break;
1344           }
1345         case 'c':
1346           {
1347             struct canvas *c = va_arg(va, struct canvas *);
1348             push_canvas(L, &c);
1349             break;
1350           }
1351         }
1352       params++;
1353       num++;
1354     }
1355   return num;
1356 }
1357
1358 int LuaCall(const char *func, const char **argv)
1359 {
1360   int argc;
1361   if (!L)
1362     return 0;
1363
1364   StackDump(L, "Before LuaCall\n");
1365   lua_getfield(L, LUA_GLOBALSINDEX, func);
1366   if (lua_isnil(L, -1))
1367     {
1368       lua_pop(L, 1);
1369       lua_pushstring(L, "Could not find the script function\n");
1370       LuaShowErr(L);
1371       return 0;
1372     }
1373   for (argc = 0; *argv; argv++, argc++)
1374     {
1375       lua_pushstring(L, *argv);
1376     }
1377   if (lua_pcall(L, argc, 0, 0) == LUA_ERRRUN)
1378     {
1379       if(lua_isstring(L, -1))
1380         {
1381           StackDump(L, "After LuaCall\n");
1382           LuaShowErr(L);
1383           return 0;
1384         }
1385     }
1386   return 1;
1387 }
1388
1389 /*** Lua callback handler management {{{ */
1390
1391 int
1392 LuaPushHTable(lua_State *L, int screen, const char * t)
1393 {
1394   lua_pushstring(L, t);
1395   lua_rawget(L, screen);
1396   /* FIXME: Do we need to balance the stack here? */
1397   if (lua_isnil(L, -1))
1398     luaL_error(L, "Fatal! Fail to get function registeration table!");
1399   return lua_gettop(L);
1400 }
1401
1402 void
1403 LuaPushHandler(lua_State *L, lua_handler lh)
1404 {
1405   int funcreg;
1406   if (lh->type == LUA_HANDLER_TYPE_F)
1407     {
1408       luaL_getmetatable(L, "screen");
1409       funcreg = LuaPushHTable(L, lua_gettop(L), "_funcreg");
1410       lua_rawgeti(L, funcreg, lh->u.reference);
1411       lua_replace(L, -3);
1412       lua_pop(L, 1);
1413     }
1414   else
1415     {
1416       lua_getfield(L, LUA_GLOBALSINDEX, lh->u.name);
1417     }
1418 }
1419
1420 int
1421 LuaFuncKey(lua_State *L, int idx, int ref)
1422 {
1423   int key, funcreg, sc;
1424   luaL_getmetatable(L, "screen");
1425   sc = lua_gettop(L);
1426   funcreg = LuaPushHTable(L, sc, "_funcreg");
1427
1428   lua_pushvalue(L, idx);
1429   key = luaL_ref(L, funcreg);
1430   lua_pop(L, 2);
1431   return key;
1432 }
1433
1434 void
1435 LuaHUnRef(lua_State *L, int key)
1436 {
1437   int funcreg, sc;
1438   luaL_getmetatable(L, "screen");
1439   sc = lua_gettop(L);
1440   funcreg = LuaPushHTable(L, sc, "_funcreg");
1441   luaL_unref(L, funcreg, key);
1442 }
1443
1444 lua_handler
1445 LuaCheckHandler(lua_State *L, int idx, int ref)
1446 {
1447   int key;
1448   if (idx < 0)
1449     idx = lua_gettop(L) + 1 - idx;
1450
1451   if (lua_isstring(L, idx))
1452     {
1453       const char * handler;
1454       /* registered with func name.*/
1455       handler = luaL_checkstring(L, idx);
1456       lua_getfield(L, LUA_GLOBALSINDEX, handler);
1457       if (!lua_isfunction(L, -1))
1458         luaL_error(L, "The specified handler %s in param #%d is not a function", handler, idx);
1459       lua_pop(L, 1);
1460       return LuaAllocHandler(handler, 0);
1461     }
1462   else if (!lua_isfunction(L, idx))
1463     luaL_error(L, "Handler should be a function or the name of function");
1464
1465   key = LuaFuncKey(L, idx, ref);
1466   return LuaAllocHandler(NULL, key);
1467 }
1468
1469 /* }}} **/
1470
1471 static int
1472 LuaDispatch(void *handler, const char *params, va_list va)
1473 {
1474   lua_handler lh = (lua_handler)handler;
1475   int argc, retvalue;
1476
1477   StackDump(L, "before dispatch");
1478
1479   LuaPushHandler(L, lh);
1480   if (lua_isnil(L, -1))
1481     {
1482       lua_pop(L, 1);
1483       return 0;
1484     }
1485   argc = LuaPushParams(L, params, va);
1486
1487   if (lua_pcall(L, argc, 1, 0) == LUA_ERRRUN && lua_isstring(L, -1))
1488     {
1489       StackDump(L, "After LuaDispatch\n");
1490       LuaShowErr(L);
1491       return 0;
1492     }
1493   retvalue = lua_tonumber(L, -1);
1494   lua_pop(L, 1);
1495   return retvalue;
1496 }
1497
1498 /*FIXME: what if a func is registered twice or more? */
1499 void
1500 LuaRegAutoUnHook(lua_State *L, lua_handler lh, int ticket)
1501 {
1502   int sc, funcunhook;
1503   luaL_getmetatable(L, "screen");
1504   sc = lua_gettop(L);
1505   funcunhook = LuaPushHTable(L, sc, "_funcunhook");
1506   LuaPushHandler(L, lh);
1507   lua_pushvalue(L, ticket);
1508   lua_rawset(L, funcunhook);
1509   lua_pop(L, 2);
1510 }
1511
1512 #define SEVNAME_MAX 30
1513 static int
1514 LuaRegEvent(lua_State *L)
1515 {
1516   /* signature: hook(obj, event, handler, priv);
1517    *        or: hook(event, handler, priv)
1518    *   returns: A ticket for later unregister. */
1519   int idx = 1, argc = lua_gettop(L);
1520   unsigned int priv = 31; /* Default privilege */
1521   lua_handler lh;
1522
1523   char *obj = NULL;
1524   const char *objname = "global";
1525
1526   static char evbuf[SEVNAME_MAX];
1527   const char *event;
1528
1529   struct script_event *sev;
1530
1531   StackDump(L, "Before RegEvent\n");
1532
1533   /* Identify the object, if specified */
1534   if (luaL_getmetafield(L, 1, "_objname"))
1535     {
1536       objname = luaL_checkstring(L, -1);
1537       lua_pop(L, 1);
1538       if (!strcmp("screen", objname))
1539         objname = "global";
1540       else
1541         {
1542           obj = get_broker_obj((struct broker **)lua_touserdata(L, 1));
1543           if (!obj)
1544             return luaL_error(L, "Invalid object specified");
1545         }
1546       idx++;
1547     }
1548
1549   event = luaL_checkstring(L, idx++);
1550   snprintf(evbuf, SEVNAME_MAX, "%s_%s", objname, event);
1551
1552   /* Check and get the handler */
1553   lh = LuaCheckHandler(L, idx++, 1);
1554   if (!lh)
1555     luaL_error(L, "Out of memory");
1556
1557   StackDump(L, "In RegEvent\n");
1558
1559   if (idx <= argc)
1560     priv = luaL_checkinteger(L, idx);
1561
1562   sev = object_get_event(obj, evbuf);
1563   if (sev)
1564     {
1565       struct listener *l;
1566       int ticket;
1567       l = (struct listener *)malloc(sizeof(struct listener));
1568       if (!l)
1569         return luaL_error(L, "Out of memory");
1570       l->priv = priv;
1571       l->bd = &lua_binding;
1572       l->handler = (void *)lh;
1573       register_listener(sev, l);
1574       /* Return the ticket for un-register */
1575       push_callback(L, &l);
1576       ticket = lua_gettop(L);
1577
1578       LuaRegAutoUnHook(L, lh, ticket);
1579     }
1580   else
1581     return luaL_error(L, "Invalid event specified: %s for object %s", event, objname);
1582
1583   StackDump(L, "After RegEvent\n");
1584   return 1;
1585 }
1586
1587 /** }}} */
1588
1589 struct binding lua_binding =
1590 {
1591     "lua", /*name*/
1592     0,     /*inited*/
1593     0,     /*registered*/
1594     LuaInit,
1595     LuaFinit,
1596     LuaCall,
1597     LuaSource,
1598     LuaDispatch,
1599     0,     /*b_next*/
1600 };
1601