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
  82 static int LuaDispatch(void *handler, const char *params, va_list va);
  83 static int LuaRegEvent(lua_State *L);
  84 static void LuaShowErr(lua_State *L);
  85 struct binding lua_binding;
  86
  87 enum
  88 {
  89   LUA_HANDLER_TYPE_N = 1,
  90   LUA_HANDLER_TYPE_F
  91 };
  92
  93 struct lua_handler
  94 {
  95   int type;
  96   union
  97   {
  98     const char *name;
  99     int reference;
 100   } u;
 101 };
 102
 103 typedef struct lua_handler *lua_handler;
 104 void LuaPushHandler(lua_State *L, lua_handler lh);
 105 void LuaHUnRef(lua_State *L, int key);
 106 lua_handler LuaCheckHandler(lua_State *L, int idx, int ref);
 107
 108 lua_handler
 109 LuaAllocHandler(const char *name, int ref)
 110 {
 111   struct lua_handler *lh;
 112   lh = (struct lua_handler*) malloc(sizeof(struct lua_handler));
 113   if (!lh)
 114     return NULL;
 115
 116   if (name)
 117     {
 118       lh->type = LUA_HANDLER_TYPE_N;
 119       lh->u.name = SaveStr(name);
 120     }
 121   else
 122     {
 123       lh->type = LUA_HANDLER_TYPE_F;
 124       lh->u.reference = ref;
 125     }
 126
 127   return lh;
 128 }
 129
 130 void
 131 LuaFreeHandler(lua_State *L, struct lua_handler **lh)
 132 {
 133   if ((*lh)->type == LUA_HANDLER_TYPE_N)
 134     Free((*lh)->u.name)
 135   else
 136     {
 137       LuaHUnRef(L, (*lh)->u.reference);
 138       (*lh)->u.reference = 0;
 139     }
 140   Free(*lh);
 141 }
 142 /** Template {{{ */
 143
 144 #define CHECK_TYPE(name, type) \
 145 static type * \
 146 check_##name(lua_State *L, int index) \
 147 { \
 148   type **var; \
 149   luaL_checktype(L, index, LUA_TUSERDATA); \
 150   var = (type **) luaL_checkudata(L, index, #name); \
 151   if (!var || !*var) \
 152     luaL_typerror(L, index, #name); \
 153   return *var; \
 154 }
 155
 156 #define PUSH_TYPE(name, type) \
 157 static void \
 158 push_##name(lua_State *L, type **t) \
 159 { \
 160   if (!t || !*t) \
 161     lua_pushnil(L); \
 162   else \
 163     { \
 164       type **r; \
 165       r = (type **)lua_newuserdata(L, sizeof(type *)); \
 166       *r = *t; \
 167       luaL_getmetatable(L, #name); \
 168       lua_setmetatable(L,-2); \
 169     } \
 170 }
 171
 172 /* Much of the following template comes from:
 173  *      http://lua-users.org/wiki/BindingWithMembersAndMethods
 174  */
 175
 176 static int get_int (lua_State *L, void *v)
 177 {
 178   lua_pushinteger (L, *(int*)v);
 179   return 1;
 180 }
 181
 182 static int set_int (lua_State *L, void *v)
 183 {
 184   *(int*)v = luaL_checkint(L, 3);
 185   return 0;
 186 }
 187
 188 static int get_number (lua_State *L, void *v)
 189 {
 190   lua_pushnumber(L, *(lua_Number*)v);
 191   return 1;
 192 }
 193
 194 static int set_number (lua_State *L, void *v)
 195 {
 196   *(lua_Number*)v = luaL_checknumber(L, 3);
 197   return 0;
 198 }
 199
 200 static int get_string (lua_State *L, void *v)
 201 {
 202   lua_pushstring(L, (char*)v );
 203   return 1;
 204 }
 205
 206 static int set_string (lua_State *L, void *v)
 207 {
 208   *(const char**)v = luaL_checkstring(L, 3);
 209   return 0;
 210 }
 211
 212 typedef int (*Xet_func) (lua_State *L, void *v);
 213
 214 /* member info for get and set handlers */
 215 struct Xet_reg
 216 {
 217   const char *name;  /* member name */
 218   Xet_func func;     /* get or set function for type of member */
 219   size_t offset;     /* offset of member within the struct */
 220   int (*absolute)(lua_State *);
 221 };
 222
 223 static void Xet_add (lua_State *L, const struct Xet_reg *l)
 224 {
 225   if (!l)
 226     return;
 227   for (; l->name; l++)
 228     {
 229       lua_pushstring(L, l->name);
 230       lua_pushlightuserdata(L, (void*)l);
 231       lua_settable(L, -3);
 232     }
 233 }
 234
 235 static int Xet_call (lua_State *L)
 236 {
 237   /* for get: stack has userdata, index, lightuserdata */
 238   /* for set: stack has userdata, index, value, lightuserdata */
 239   const struct Xet_reg *m = (const struct Xet_reg *)lua_touserdata(L, -1);  /* member info */
 240   lua_pop(L, 1);                               /* drop lightuserdata */
 241   luaL_checktype(L, 1, LUA_TUSERDATA);
 242   if (m->absolute)
 243     return m->absolute(L);
 244   return m->func(L, *(char**)lua_touserdata(L, 1) + m->offset);
 245 }
 246
 247 static int index_handler (lua_State *L)
 248 {
 249   /* stack has userdata, index */
 250   lua_pushvalue(L, 2);                     /* dup index */
 251   lua_rawget(L, lua_upvalueindex(1));      /* lookup member by name */
 252   if (!lua_islightuserdata(L, -1))
 253     {
 254       lua_pop(L, 1);                         /* drop value */
 255       lua_pushvalue(L, 2);                   /* dup index */
 256       lua_gettable(L, lua_upvalueindex(2));  /* else try methods */
 257       if (lua_isnil(L, -1))                  /* invalid member */
 258         luaL_error(L, "cannot get member '%s'", lua_tostring(L, 2));
 259       return 1;
 260     }
 261   return Xet_call(L);                      /* call get function */
 262 }
 263
 264 static int newindex_handler (lua_State *L)
 265 {
 266   /* stack has userdata, index, value */
 267   lua_pushvalue(L, 2);                     /* dup index */
 268   lua_rawget(L, lua_upvalueindex(1));      /* lookup member by name */
 269   if (!lua_islightuserdata(L, -1))         /* invalid member */
 270     luaL_error(L, "cannot set member '%s'", lua_tostring(L, 2));
 271   return Xet_call(L);                      /* call set function */
 272 }
 273
 274 static int
 275 struct_register(lua_State *L, const char *name, const luaL_reg fn_methods[], const luaL_reg meta_methods[],
 276     const struct Xet_reg setters[], const struct Xet_reg getters[])
 277 {
 278   int metatable, methods;
 279
 280   /* create methods table & add it to the table of globals */
 281   luaL_register(L, name, fn_methods);
 282   methods = lua_gettop(L);
 283
 284   /* create metatable & add it to the registry */
 285   luaL_newmetatable(L, name);
 286   luaL_register(L, 0, meta_methods);  /* fill metatable */
 287
 288   /* To identify the type of object */
 289   lua_pushstring(L, "_objname");
 290   lua_pushstring(L, name);
 291   lua_rawset(L, -3);
 292
 293   metatable = lua_gettop(L);
 294
 295   lua_pushliteral(L, "__metatable");
 296   lua_pushvalue(L, methods);    /* dup methods table*/
 297   lua_rawset(L, metatable);     /* hide metatable:
 298                                    metatable.__metatable = methods */
 299
 300   lua_pushliteral(L, "__index");
 301   lua_pushvalue(L, metatable);  /* upvalue index 1 */
 302   Xet_add(L, getters);     /* fill metatable with getters */
 303   lua_pushvalue(L, methods);    /* upvalue index 2 */
 304   lua_pushcclosure(L, index_handler, 2);
 305   lua_rawset(L, metatable);     /* metatable.__index = index_handler */
 306
 307   lua_pushliteral(L, "__newindex");
 308   lua_newtable(L);              /* table for members you can set */
 309   Xet_add(L, setters);     /* fill with setters */
 310   lua_pushcclosure(L, newindex_handler, 1);
 311   lua_rawset(L, metatable);     /* metatable.__newindex = newindex_handler */
 312
 313   /* FIXME: Why do we leave an element on the stack? */
 314   lua_pop(L, 1);                /* drop metatable */
 315   return 1;                     /* return methods on the stack */
 316 }
 317
 318 /** }}} */
 319
 320 /** Callback {{{ */
 321 PUSH_TYPE(callback, struct listener)
 322
 323 static int
 324 internal_unhook(lua_State *L, int warn)
 325 {
 326   /*Emulate check_callback() */
 327   struct listener **ppl;
 328   luaL_checktype(L, 1, LUA_TUSERDATA);
 329   ppl = (struct listener **) luaL_checkudata(L, 1, "callback");
 330
 331   if (!ppl)
 332     luaL_typerror(L, 1, "callback");
 333
 334   if (!*ppl)
 335     {
 336       if (warn)
 337         {
 338           lua_pushboolean(L, 0);
 339           lua_pushstring(L, "Callback already unhooked.");
 340           LuaShowErr(L);
 341         }
 342     }
 343   else
 344     {
 345       LuaFreeHandler(L, (lua_handler *)&(*ppl)->handler);
 346       unregister_listener(*ppl);
 347       *ppl = 0;
 348       if (warn)
 349         lua_pushboolean(L, 1);
 350     }
 351   return warn != 0;
 352 }
 353 static int
 354 callback_unhook(lua_State *L)
 355 {
 356   return internal_unhook(L, 1);
 357 }
 358
 359 static const luaL_reg callback_methods[] = {
 360   {"unhook", callback_unhook},
 361   {0, 0}
 362 };
 363
 364 int
 365 callback_collect(lua_State *L)
 366 {
 367   return internal_unhook(L, 0);
 368 }
 369
 370 static const luaL_reg callback_metamethods[] = {
 371   {"__gc", callback_collect},
 372   {0, 0}
 373 };
 374
 375 static const struct Xet_reg callback_setters[] = {
 376   {0, 0}
 377 };
 378
 379 static const struct Xet_reg callback_getters[] = {
 380   {0, 0}
 381 };
 382
 383
 384 /** }}} */
 385
 386 /** Window {{{ */
 387
 388 PUSH_TYPE(window, struct win)
 389
 390 CHECK_TYPE(window, struct win)
 391
 392 static int get_window(lua_State *L, void *v)
 393 {
 394   push_window(L, (struct win **)v);
 395   return 1;
 396 }
 397
 398 static int
 399 window_change_title(lua_State *L)
 400 {
 401   struct win *w = check_window(L, 1);
 402   unsigned int len;
 403   const char *title = luaL_checklstring(L, 3, &len);
 404   ChangeAKA(w, (char *)title, len);
 405   return 0;
 406 }
 407
 408 static int
 409 window_change_number(lua_State *L)
 410 {
 411   struct win *w = check_window(L, 1);
 412   int newnum = luaL_checkint(L, 3);
 413   ChangeWinNum(w->w_number, newnum);
 414   return 0;
 415 }
 416
 417 static int
 418 window_get_monitor_status(lua_State *L)
 419 {
 420   struct win *w = check_window(L, 1);
 421   int activity = luaL_checkint(L, 2);
 422   if (activity)
 423     /*monitor*/
 424     lua_pushinteger(L, w->w_monitor != MON_OFF);
 425   else
 426     /*silence*/
 427     lua_pushinteger(L, w->w_silence == SILENCE_ON ? w->w_silencewait: 0);
 428
 429   return 1;
 430 }
 431
 432 static int
 433 window_stuff(lua_State *L)
 434 {
 435   unsigned int len;
 436   struct layer *oldflayer = flayer;
 437   struct win *w = check_window(L, 1);
 438   const char *str = luaL_checklstring(L, 2, &len);
 439
 440   flayer = &w->w_layer;
 441   while(len)
 442     LayProcess((char **)&str, (int *) &len);
 443   flayer = oldflayer;
 444   return 0;
 445 }
 446
 447 static const luaL_reg window_methods[] = {
 448   {"get_monitor_status", window_get_monitor_status},
 449   {"stuff", window_stuff},
 450   {"hook", LuaRegEvent},
 451   {0, 0}
 452 };
 453
 454 static int
 455 window_tostring(lua_State *L)
 456 {
 457   char str[128];
 458   struct win *w = check_window(L, 1);
 459   snprintf(str, sizeof(str), "{window #%d: '%s'}", w->w_number, w->w_title);
 460   lua_pushstring(L, str);
 461   return 1;
 462 }
 463
 464 static int
 465 window_equality(lua_State *L)
 466 {
 467   struct win *w1 = check_window(L, 1), *w2 = check_window(L, 2);
 468   lua_pushboolean(L, (w1 == w2 || (w1 && w2 && w1->w_number == w2->w_number)));
 469   return 1;
 470 }
 471
 472 static const luaL_reg window_metamethods[] = {
 473   {"__tostring", window_tostring},
 474   {"__eq", window_equality},
 475   {0, 0}
 476 };
 477
 478 static const struct Xet_reg window_setters[] = {
 479   {"title", 0, 0, window_change_title/*absolute setter*/},
 480   {"number", 0, 0, window_change_number/*absolute setter*/},
 481   {0, 0}
 482 };
 483
 484 static const struct Xet_reg window_getters[] = {
 485   {"title", get_string, offsetof(struct win, w_title) + 8},
 486   {"number", get_int, offsetof(struct win, w_number)},
 487   {"dir", get_string, offsetof(struct win, w_dir)},
 488   {"tty", get_string, offsetof(struct win, w_tty)},
 489   {"pid", get_int, offsetof(struct win, w_pid)},
 490   {"group", get_window, offsetof(struct win, w_group)},
 491   {"bell", get_int, offsetof(struct win, w_bell)},
 492   {0, 0}
 493 };
 494
 495
 496 /** }}} */
 497
 498 /** AclUser {{{ */
 499
 500 PUSH_TYPE(user, struct acluser)
 501
 502 CHECK_TYPE(user, struct acluser)
 503
 504 static int
 505 get_user(lua_State *L, void *v)
 506 {
 507   push_user(L, (struct acluser **)v);
 508   return 1;
 509 }
 510
 511 static const luaL_reg user_methods[] = {
 512   {0, 0}
 513 };
 514
 515 static int
 516 user_tostring(lua_State *L)
 517 {
 518   char str[128];
 519   struct acluser *u = check_user(L, 1);
 520   snprintf(str, sizeof(str), "{user '%s'}", u->u_name);
 521   lua_pushstring(L, str);
 522   return 1;
 523 }
 524
 525 static const luaL_reg user_metamethods[] = {
 526   {"__tostring", user_tostring},
 527   {0, 0}
 528 };
 529
 530 static const struct Xet_reg user_setters[] = {
 531   {0, 0}
 532 };
 533
 534 static const struct Xet_reg user_getters[] = {
 535   {"name", get_string, offsetof(struct acluser, u_name)},
 536   {"password", get_string, offsetof(struct acluser, u_password)},
 537   {0, 0}
 538 };
 539
 540 /** }}} */
 541
 542 /** Canvas {{{ */
 543
 544 PUSH_TYPE(canvas, struct canvas)
 545
 546 CHECK_TYPE(canvas, struct canvas)
 547
 548 static int
 549 get_canvas(lua_State *L, void *v)
 550 {
 551   push_canvas(L, (struct canvas **)v);
 552   return 1;
 553 }
 554
 555 static int
 556 canvas_select(lua_State *L)
 557 {
 558   struct canvas *c = check_canvas(L, 1);
 559   if (!display || D_forecv == c)
 560     return 0;
 561   /* FIXME: why do we need this? */
 562   SetCanvasWindow(c, Layer2Window(c->c_layer));
 563
 564   FocusCanvas(c);
 565   return 0;
 566 }
 567
 568 static const luaL_reg canvas_methods[] = {
 569   {"select", canvas_select},
 570   {0, 0}
 571 };
 572
 573 static const luaL_reg canvas_metamethods[] = {
 574   {0, 0}
 575 };
 576
 577 static const struct Xet_reg canvas_setters[] = {
 578   {0, 0}
 579 };
 580
 581 static int
 582 canvas_get_window(lua_State *L)
 583 {
 584   struct canvas *c = check_canvas(L, 1);
 585   struct win *win = Layer2Window(c->c_layer);
 586   if (win)
 587     push_window(L, &win);
 588   else
 589     lua_pushnil(L);
 590   return 1;
 591 }
 592
 593 static const struct Xet_reg canvas_getters[] = {
 594   {"next", get_canvas, offsetof(struct canvas, c_next)},
 595   {"xoff", get_int, offsetof(struct canvas, c_xoff)},
 596   {"yoff", get_int, offsetof(struct canvas, c_yoff)},
 597   {"xs", get_int, offsetof(struct canvas, c_xs)},
 598   {"ys", get_int, offsetof(struct canvas, c_ys)},
 599   {"xe", get_int, offsetof(struct canvas, c_xe)},
 600   {"ye", get_int, offsetof(struct canvas, c_ye)},
 601   {"window", 0, 0, canvas_get_window},
 602   {0, 0}
 603 };
 604
 605 /** }}} */
 606
 607 /** Layout {{{ */
 608
 609 PUSH_TYPE(layout, struct layout)
 610 CHECK_TYPE(layout, struct layout)
 611
 612 static const struct Xet_reg layout_getters[] = {
 613       {0,0}
 614 };
 615
 616 static int
 617 get_layout(lua_State *L, void *v)
 618 {
 619   push_layout(L, (struct layout **)v);
 620   return 1;
 621 }
 622
 623 /** }}} */
 624
 625 /** Display {{{ */
 626
 627 PUSH_TYPE(display, struct display)
 628
 629 CHECK_TYPE(display, struct display)
 630
 631 static int
 632 display_get_canvases(lua_State *L)
 633 {
 634   struct display *d;
 635   struct canvas *iter;
 636   int count;
 637
 638   d = check_display(L, 1);
 639   lua_newtable(L);
 640   for (iter = d->d_cvlist, count = 0; iter; iter = iter->c_next, count++) {
 641     lua_pushinteger(L, count);
 642     push_canvas(L, &iter);
 643     lua_settable(L, -3);
 644   }
 645
 646   return 1;
 647 }
 648
 649 static const luaL_reg display_methods[] = {
 650   {"get_canvases", display_get_canvases},
 651   {0, 0}
 652 };
 653
 654 static int
 655 display_tostring(lua_State *L)
 656 {
 657   char str[128];
 658   struct display *d = check_display(L, 1);
 659   snprintf(str, sizeof(str), "{display: tty = '%s', term = '%s'}", d->d_usertty, d->d_termname);
 660   lua_pushstring(L, str);
 661   return 1;
 662 }
 663
 664 static const luaL_reg display_metamethods[] = {
 665   {"__tostring", display_tostring},
 666   {0, 0}
 667 };
 668
 669 static const struct Xet_reg display_setters[] = {
 670   {0, 0}
 671 };
 672
 673 static const struct Xet_reg display_getters[] = {
 674   {"tty", get_string, offsetof(struct display, d_usertty)},
 675   {"term", get_string, offsetof(struct display, d_termname)},
 676   {"fore", get_window, offsetof(struct display, d_fore)},
 677   {"other", get_window, offsetof(struct display, d_other)},
 678   {"width", get_int, offsetof(struct display, d_width)},
 679   {"height", get_int, offsetof(struct display, d_height)},
 680   {"user", get_user, offsetof(struct display, d_user)},
 681   {"layout", get_layout, offsetof(struct display, d_layout)},
 682   {0, 0}
 683 };
 684
 685 /** }}} */
 686
 687 /** Screen {{{ */
 688
 689 static int
 690 screen_get_windows(lua_State *L)
 691 {
 692   struct win *iter;
 693   int count;
 694
 695   lua_newtable(L);
 696   for (iter = windows, count = 0; iter; iter = iter->w_next, count++) {
 697     lua_pushinteger(L, iter->w_number);
 698     push_window(L, &iter);
 699     lua_settable(L, -3);
 700   }
 701
 702   return 1;
 703 }
 704
 705 static int
 706 screen_get_displays(lua_State *L)
 707 {
 708   struct display *iter;
 709   int count;
 710
 711   lua_newtable(L);
 712   for (iter = displays, count = 0; iter; iter = iter->d_next, count++) {
 713     lua_pushinteger(L, count);
 714     push_display(L, &iter);
 715     lua_settable(L, -3);
 716   }
 717
 718   return 1;
 719 }
 720
 721 static int
 722 screen_get_display(lua_State *L)
 723 {
 724   push_display(L, &display);
 725   return 1;
 726 }
 727
 728 static int
 729 screen_exec_command(lua_State *L)
 730 {
 731   const char *command;
 732   unsigned int len;
 733
 734   command = luaL_checklstring(L, 1, &len);
 735   if (command)
 736     RcLine((char *)command, len);
 737
 738   return 0;
 739 }
 740
 741 static int
 742 screen_append_msg(lua_State *L)
 743 {
 744   const char *msg, *color;
 745   unsigned int len;
 746   msg = luaL_checklstring(L, 1, &len);
 747   if (lua_isnil(L, 2))
 748     color = NULL;
 749   else
 750     color = luaL_checklstring(L, 2, &len);
 751   AppendWinMsgRend(msg, color);
 752   return 0;
 753 }
 754
 755 struct sinput_data
 756 {
 757   lua_State *L;
 758   lua_handler lh;
 759 };
 760
 761 void
 762 script_input_fn(char *buf, int len, char *priv)
 763 {
 764   struct sinput_data *sidata = (struct sinput_data *)priv;
 765   lua_handler lh = sidata->lh;
 766   lua_State *L = sidata->L;
 767
 768   LuaPushHandler(L, lh);
 769   lua_pushstring(L, buf);
 770   if (lua_pcall(L, 1, 0, 0) == LUA_ERRRUN)
 771     {
 772       if(lua_isstring(L, -1))
 773         {
 774           LuaShowErr(L);
 775         }
 776     }
 777   free(sidata);
 778   LuaFreeHandler(L, &lh);
 779 }
 780
 781 static int
 782 screen_input(lua_State *L)
 783 {
 784   char *ss;
 785   int n;
 786   const char * prompt = NULL, *prefill = NULL;
 787   lua_handler lh;
 788   struct sinput_data *sidata;
 789
 790   prompt = luaL_checkstring(L, 1);
 791   lh = LuaCheckHandler(L, 2, 1);
 792   if (!lh)
 793     luaL_error(L, "Out of Memory");
 794
 795   if (lua_gettop(L) >= 3)
 796     prefill = luaL_checkstring(L, 3);
 797
 798
 799   sidata = (struct sinput_data *)malloc(sizeof(struct sinput_data));
 800   if (!sidata)
 801     {
 802       Free(lh);
 803       luaL_error(L, "Out of Memory");
 804     }
 805
 806   sidata->L = L;
 807   sidata->lh = lh;
 808   Input((char *)prompt, 100, INP_COOKED, script_input_fn, (char *)sidata, 0);
 809
 810   if (!prefill)
 811     return 0;
 812   for (; *prefill; prefill++)
 813     {
 814       if ((*(unsigned char *)prefill & 0x7f) < 0x20 || *prefill == 0x7f)
 815         continue;
 816       ss = (char *)prefill;
 817       n = 1;
 818       LayProcess(&ss, &n);
 819     }
 820   return 0;
 821 }
 822
 823 static const luaL_reg screen_methods[] = {
 824   {"windows", screen_get_windows},
 825   {"displays", screen_get_displays},
 826   {"display", screen_get_display},
 827   {"command", screen_exec_command},
 828   {"append_msg", screen_append_msg},
 829   {"hook", LuaRegEvent},
 830   {"input", screen_input},
 831   {0, 0}
 832 };
 833
 834 static const luaL_reg screen_metamethods[] = {
 835   {0, 0}
 836 };
 837
 838 static const struct Xet_reg screen_setters[] = {
 839   {0, 0}
 840 };
 841
 842 static const struct Xet_reg screen_getters[] = {
 843   {0, 0}
 844 };
 845
 846 /** }}} */
 847
 848 /** Public functions {{{ */
 849
 850 /* FIXME: This code only tracks one unhook ticket for a lua func.
 851  * So it does not work if one func is registered more than one times. */
 852 static void
 853 prepare_weak_table(lua_State *L, const char *name, const char *mode)
 854 {
 855   luaL_getmetatable(L, "screen");
 856
 857   lua_pushstring(L, name);
 858   lua_newtable(L);
 859
 860   /* prepare a metatable to indicate weak table */
 861   lua_newtable(L);
 862   lua_pushstring(L, "__mode");
 863   lua_pushstring(L, mode);
 864   lua_rawset(L, -3);
 865   /* Mark weak table */
 866   lua_setmetatable(L, -2);
 867   lua_rawset(L, -3);
 868   lua_pop(L, 1);
 869 }
 870
 871 static lua_State *L;
 872 int LuaInit(void)
 873 {
 874   L = luaL_newstate();
 875
 876   luaL_openlibs(L);
 877
 878 #define REGISTER(X) struct_register(L, #X , X ## _methods, X##_metamethods, X##_setters, X##_getters)
 879
 880   REGISTER(screen);
 881   REGISTER(window);
 882   REGISTER(display);
 883   REGISTER(user);
 884   REGISTER(canvas);
 885   REGISTER(callback);
 886
 887   /* To store handler funcs */
 888
 889   /*_two kinds of information are mantained:
 890    *
 891    * funcreg[key]->func
 892    * The 'func' part of the tables are weak. That means the registered funcs
 893    * will be collected once the func is no longer available (e.g. overwritten
 894    * by a new instance of the script)
 895    *
 896    * To make this process happens faster, GC is forced at the end of each
 897    * source.
 898    * TODO: What if some events are triggered within the sourcing
 899    * procedure?
 900    * */
 901   prepare_weak_table(L, "_funcreg", "v");
 902
 903   /* funcunhook[func]->listener
 904    * The listener is the unhook ticket of the hook. which should be collected
 905    * once the func is collected. The gc metamethod will be triggered
 906    * accordingly. */
 907   prepare_weak_table(L, "_funcunhook", "k");
 908
 909   return 0;
 910 }
 911
 912 /* An error message on top of the stack. */
 913 static void
 914 LuaShowErr(lua_State *L)
 915 {
 916   struct display *d = display;
 917   unsigned int len;
 918   const char *message = luaL_checklstring(L, -1, &len);
 919   LMsg(0, "%s", message ? message : "Unknown error");
 920   lua_pop(L, 1);
 921   display = d;
 922 }
 923
 924 struct fn_def
 925 {
 926   void (*push_fn)(lua_State *, void*);
 927   void *value;
 928 };
 929
 930 static int
 931 LuaCallProcess(const char *name, struct fn_def defs[])
 932 {
 933   int argc = 0;
 934
 935   lua_getfield(L, LUA_GLOBALSINDEX, name);
 936   if (lua_isnil(L, -1))
 937     {
 938       lua_pop(L,1);
 939       return 0;
 940     }
 941   for (argc = 0; defs[argc].push_fn; argc++)
 942     defs[argc].push_fn(L, defs[argc].value);
 943   if (lua_pcall(L, argc, 0, 0) == LUA_ERRRUN && lua_isstring(L, -1))
 944     {
 945       LuaShowErr(L);
 946       return 0;
 947     }
 948   return 1;
 949 }
 950
 951 /* FIXME: Think about this: will it affect the registered handlers?*/
 952 int LuaSource(const char *file, int async)
 953 {
 954   if (!L)
 955     return 0;
 956   struct stat st;
 957   if (stat(file, &st) == -1)
 958     Msg(errno, "Error loading lua script file '%s'", file);
 959   else
 960     {
 961       int len = strlen(file);
 962       if (len < 4 || strncmp(file + len - 4, ".lua", 4) != 0)
 963         return 0;
 964       if (luaL_dofile(L, file) && lua_isstring(L, -1))
 965         {
 966           LuaShowErr(L);
 967           return 0;
 968         }
 969       else
 970         {
 971           /* It seems that I need two GC passes to really collect the unhook
 972            * ticket, after changing the reference to ticket in the
 973            * 'funcunhook' table from weak to strong. This should not be
 974            * harmful, but how can I make sure that two passes is enough?
 975            *
 976            * Possible reason:
 977            * This seems reasonable, since the first pass will collect the func
 978            * itself and make the ticket garbage, and the second pass will
 979            * collect the ticket itself.
 980            *
 981            * TODO: check this out. maybe ask some lua gurus. */
 982           lua_gc(L, LUA_GCCOLLECT, 0);
 983           lua_gc(L, LUA_GCCOLLECT, 0);
 984         }
 985       return 1;
 986     }
 987   return 0;
 988 }
 989
 990 int LuaFinit(void)
 991 {
 992   if (!L)
 993     return 0;
 994   lua_close(L);
 995   L = (lua_State*)0;
 996   return 0;
 997 }
 998
 999 int
1000 LuaProcessCaption(const char *caption, struct win *win, int len)
1001 {
1002   if (!L)
1003     return 0;
1004   struct fn_def params[] = {
1005     {lua_pushstring, caption},
1006     {push_window, &win},
1007     {lua_pushinteger, len},
1008     {NULL, NULL}
1009   };
1010   return LuaCallProcess("process_caption", params);
1011 }
1012
1013 static void
1014 push_stringarray(lua_State *L, char **args)
1015 {
1016   int i;
1017   lua_newtable(L);
1018   for (i = 1; args && *args; i++) {
1019     lua_pushinteger(L, i);
1020     lua_pushstring(L, *args++);
1021     lua_settable(L, -3);
1022   }
1023 }
1024
1025 int
1026 LuaPushParams(lua_State *L, const char *params, va_list va)
1027 {
1028   int num = 0;
1029   while (*params)
1030     {
1031       switch (*params)
1032         {
1033         case 's':
1034           lua_pushstring(L, va_arg(va, char *));
1035           break;
1036         case 'S':
1037           push_stringarray(L, va_arg(va, char **));
1038           break;
1039         case 'i':
1040           lua_pushinteger(L, va_arg(va, int));
1041           break;
1042         case 'd':
1043           {
1044             struct display *d = va_arg(va, struct display *);
1045             push_display(L, &d);
1046             break;
1047           }
1048         case 'w':
1049           {
1050             struct win *w = va_arg(va, struct win *);
1051             push_window(L, &w);
1052             break;
1053           }
1054         }
1055       params++;
1056       num++;
1057     }
1058   return num;
1059 }
1060
1061 int LuaCall(const char *func, const char **argv)
1062 {
1063   int argc;
1064   if (!L)
1065     return 0;
1066
1067   StackDump(L, "Before LuaCall\n");
1068   lua_getfield(L, LUA_GLOBALSINDEX, func);
1069   if (lua_isnil(L, -1))
1070     {
1071       lua_pop(L, 1);
1072       lua_pushstring(L, "Could not find the script function\n");
1073       LuaShowErr(L);
1074       return 0;
1075     }
1076   for (argc = 0; *argv; argv++, argc++)
1077     {
1078       lua_pushstring(L, *argv);
1079     }
1080   if (lua_pcall(L, argc, 0, 0) == LUA_ERRRUN)
1081     {
1082       if(lua_isstring(L, -1))
1083         {
1084           StackDump(L, "After LuaCall\n");
1085           LuaShowErr(L);
1086           return 0;
1087         }
1088     }
1089   return 1;
1090 }
1091
1092 /*** Lua callback handler management {{{ */
1093
1094 int
1095 LuaPushHTable(lua_State *L, int screen, const char * t)
1096 {
1097   lua_pushstring(L, t);
1098   lua_rawget(L, screen);
1099   /* FIXME: Do we need to balance the stack here? */
1100   if (lua_isnil(L, -1))
1101     luaL_error(L, "Fatal! Fail to get function registeration table!");
1102   return lua_gettop(L);
1103 }
1104
1105 void
1106 LuaPushHandler(lua_State *L, lua_handler lh)
1107 {
1108   int funcreg;
1109   if (lh->type == LUA_HANDLER_TYPE_F)
1110     {
1111       luaL_getmetatable(L, "screen");
1112       funcreg = LuaPushHTable(L, lua_gettop(L), "_funcreg");
1113       lua_rawgeti(L, funcreg, lh->u.reference);
1114       lua_replace(L, -3);
1115       lua_pop(L, 1);
1116     }
1117   else
1118     {
1119       lua_getfield(L, LUA_GLOBALSINDEX, lh->u.name);
1120     }
1121 }
1122
1123 int
1124 LuaFuncKey(lua_State *L, int idx, int ref)
1125 {
1126   int key, funcreg, sc;
1127   luaL_getmetatable(L, "screen");
1128   sc = lua_gettop(L);
1129   funcreg = LuaPushHTable(L, sc, "_funcreg");
1130
1131   lua_pushvalue(L, idx);
1132   key = luaL_ref(L, funcreg);
1133   lua_pop(L, 2);
1134   return key;
1135 }
1136
1137 void
1138 LuaHUnRef(lua_State *L, int key)
1139 {
1140   int funcreg, sc;
1141   luaL_getmetatable(L, "screen");
1142   sc = lua_gettop(L);
1143   funcreg = LuaPushHTable(L, sc, "_funcreg");
1144   luaL_unref(L, funcreg, key);
1145 }
1146
1147 lua_handler
1148 LuaCheckHandler(lua_State *L, int idx, int ref)
1149 {
1150   int key;
1151   if (idx < 0)
1152     idx = lua_gettop(L) + 1 - idx;
1153
1154   if (lua_isstring(L, idx))
1155     {
1156       const char * handler;
1157       /* registered with func name.*/
1158       handler = luaL_checkstring(L, idx);
1159       lua_getfield(L, LUA_GLOBALSINDEX, handler);
1160       if (!lua_isfunction(L, -1))
1161         luaL_error(L, "The specified handler %s in param #%d is not a function", handler, idx);
1162       lua_pop(L, 1);
1163       return LuaAllocHandler(handler, 0);
1164     }
1165   else if (!lua_isfunction(L, idx))
1166     luaL_error(L, "Handler should be a function or the name of function");
1167
1168   key = LuaFuncKey(L, idx, ref);
1169   return LuaAllocHandler(NULL, key);
1170 }
1171
1172 /* }}} **/
1173
1174 static int
1175 LuaDispatch(void *handler, const char *params, va_list va)
1176 {
1177   lua_handler lh = (lua_handler)handler;
1178   int argc, retvalue;
1179
1180   StackDump(L, "before dispatch");
1181
1182   LuaPushHandler(L, lh);
1183   if (lua_isnil(L, -1))
1184     {
1185       lua_pop(L, 1);
1186       return 0;
1187     }
1188   argc = LuaPushParams(L, params, va);
1189
1190   if (lua_pcall(L, argc, 1, 0) == LUA_ERRRUN && lua_isstring(L, -1))
1191     {
1192       StackDump(L, "After LuaDispatch\n");
1193       LuaShowErr(L);
1194       return 0;
1195     }
1196   retvalue = lua_tonumber(L, -1);
1197   lua_pop(L, 1);
1198   return retvalue;
1199 }
1200
1201 /*FIXME: what if a func is registered twice or more? */
1202 void
1203 LuaRegAutoUnHook(lua_State *L, lua_handler lh, int ticket)
1204 {
1205   int sc, funcunhook;
1206   luaL_getmetatable(L, "screen");
1207   sc = lua_gettop(L);
1208   funcunhook = LuaPushHTable(L, sc, "_funcunhook");
1209   LuaPushHandler(L, lh);
1210   lua_pushvalue(L, ticket);
1211   lua_rawset(L, funcunhook);
1212   lua_pop(L, 2);
1213 }
1214
1215 #define SEVNAME_MAX 30
1216 static int
1217 LuaRegEvent(lua_State *L)
1218 {
1219   /* signature: hook(obj, event, handler, priv);
1220    *        or: hook(event, handler, priv)
1221    *   returns: A ticket for later unregister. */
1222   int idx = 1, argc = lua_gettop(L);
1223   unsigned int priv = 31; /* Default privilege */
1224   lua_handler lh;
1225
1226   char *obj = NULL;
1227   const char *objname = "global";
1228
1229   static char evbuf[SEVNAME_MAX];
1230   const char *event;
1231
1232   struct script_event *sev;
1233
1234   StackDump(L, "Before RegEvent\n");
1235
1236   /* Identify the object, if specified */
1237   if (luaL_getmetafield(L, 1, "_objname"))
1238     {
1239       objname = luaL_checkstring(L, -1);
1240       lua_pop(L, 1);
1241       if (!strcmp("screen", objname))
1242         objname = "global";
1243       else
1244         obj = *(char **)lua_touserdata(L, 1);
1245       idx++;
1246     }
1247
1248   event = luaL_checkstring(L, idx++);
1249   snprintf(evbuf, SEVNAME_MAX, "%s_%s", objname, event);
1250
1251   /* Check and get the handler */
1252   lh = LuaCheckHandler(L, idx++, 1);
1253   if (!lh)
1254     luaL_error(L, "Out of memory");
1255
1256   StackDump(L, "In RegEvent\n");
1257
1258   if (idx <= argc)
1259     priv = luaL_checkinteger(L, idx);
1260
1261   sev = object_get_event(obj, evbuf);
1262   if (sev)
1263     {
1264       struct listener *l;
1265       int ticket;
1266       l = (struct listener *)malloc(sizeof(struct listener));
1267       if (!l)
1268         return luaL_error(L, "Out of memory");
1269       l->priv = priv;
1270       l->bd = &lua_binding;
1271       l->handler = (void *)lh;
1272       register_listener(sev, l);
1273       /* Return the ticket for un-register */
1274       push_callback(L, &l);
1275       ticket = lua_gettop(L);
1276
1277       LuaRegAutoUnHook(L, lh, ticket);
1278     }
1279   else
1280     return luaL_error(L, "Invalid event specified: %s for object %s", event, objname);
1281
1282   StackDump(L, "After RegEvent\n");
1283   return 1;
1284 }
1285
1286 /** }}} */
1287
1288 struct ScriptFuncs LuaFuncs =
1289 {
1290   LuaProcessCaption
1291 };
1292
1293 struct binding lua_binding =
1294 {
1295     "lua", /*name*/
1296     0,     /*inited*/
1297     0,     /*registered*/
1298     LuaInit,
1299     LuaFinit,
1300     LuaCall,
1301     LuaSource,
1302     LuaDispatch,
1303     0,     /*b_next*/
1304     &LuaFuncs
1305 };
1306