src/lua.c

   1 /* Lua scripting support
   2  *
   3  * Copyright (c) 2008 Sadrul Habib Chowdhury (sadrul@users.sf.net)
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 3, or (at your option)
   8  * any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program (see the file COPYING); if not, write to the
  17  * Free Software Foundation, Inc.,
  18  * 51 Franklin Street, Fifth Floor, Boston, MA  02111-1301  USA
  19  *
  20  ****************************************************************
  21  */
  22 #include <sys/types.h>
  23 #include <sys/stat.h>
  24 #include <unistd.h>
  25
  26 #include <stdio.h>
  27 #include <string.h>
  28 #include <stdlib.h>
  29
  30 #include "config.h"
  31
  32 #include "screen.h"
  33 #include "extern.h"
  34 #include "logfile.h"
  35
  36 #include <lua.h>
  37 #include <lauxlib.h>
  38 #include <lualib.h>
  39
  40 extern struct win *windows, *fore;
  41 extern struct display *displays, *display;
  42 extern struct LayFuncs WinLf;
  43 extern struct layer *flayer;
  44
  45 /** Template {{{ */
  46
  47 #define CHECK_TYPE(name, type) \
  48 static type * \
  49 check_##name(lua_State *L, int index) \
  50 { \
  51   type *var; \
  52   luaL_checktype(L, index, LUA_TUSERDATA); \
  53   var = (type *) luaL_checkudata(L, index, #name); \
  54   if (!var) \
  55     luaL_typerror(L, index, #name); \
  56   return var; \
  57 }
  58
  59 #define PUSH_TYPE(name, type) \
  60 static void \
  61 push_##name(lua_State *L, type *t) \
  62 { \
  63   if (!t) \
  64     lua_pushnil(L); \
  65   else \
  66     { \
  67       type *r; \
  68       r = (type *)lua_newuserdata(L, sizeof(type)); \
  69       *r = *t; \
  70       luaL_getmetatable(L, #name); \
  71       lua_setmetatable(L,-2); \
  72     } \
  73 }
  74
  75 /* Much of the following template comes from:
  76  *      http://lua-users.org/wiki/BindingWithMembersAndMethods
  77  */
  78
  79 static int get_int (lua_State *L, void *v)
  80 {
  81   lua_pushinteger (L, *(int*)v);
  82   return 1;
  83 }
  84
  85 static int set_int (lua_State *L, void *v)
  86 {
  87   *(int*)v = luaL_checkint(L, 3);
  88   return 0;
  89 }
  90
  91 static int get_number (lua_State *L, void *v)
  92 {
  93   lua_pushnumber(L, *(lua_Number*)v);
  94   return 1;
  95 }
  96
  97 static int set_number (lua_State *L, void *v)
  98 {
  99   *(lua_Number*)v = luaL_checknumber(L, 3);
 100   return 0;
 101 }
 102
 103 static int get_string (lua_State *L, void *v)
 104 {
 105   lua_pushstring(L, (char*)v );
 106   return 1;
 107 }
 108
 109 static int set_string (lua_State *L, void *v)
 110 {
 111   *(const char**)v = luaL_checkstring(L, 3);
 112   return 0;
 113 }
 114
 115 typedef int (*Xet_func) (lua_State *L, void *v);
 116
 117 /* member info for get and set handlers */
 118 struct Xet_reg
 119 {
 120   const char *name;  /* member name */
 121   Xet_func func;     /* get or set function for type of member */
 122   size_t offset;     /* offset of member within the struct */
 123   int (*absolute)(lua_State *);
 124 };
 125
 126 static void Xet_add (lua_State *L, const struct Xet_reg *l)
 127 {
 128   if (!l)
 129     return;
 130   for (; l->name; l++)
 131     {
 132       lua_pushstring(L, l->name);
 133       lua_pushlightuserdata(L, (void*)l);
 134       lua_settable(L, -3);
 135     }
 136 }
 137
 138 static int Xet_call (lua_State *L)
 139 {
 140   /* for get: stack has userdata, index, lightuserdata */
 141   /* for set: stack has userdata, index, value, lightuserdata */
 142   const struct Xet_reg *m = (const struct Xet_reg *)lua_touserdata(L, -1);  /* member info */
 143   lua_pop(L, 1);                               /* drop lightuserdata */
 144   luaL_checktype(L, 1, LUA_TUSERDATA);
 145   if (m->absolute)
 146     return m->absolute(L);
 147   return m->func(L, lua_touserdata(L, 1) + m->offset);
 148 }
 149
 150 static int index_handler (lua_State *L)
 151 {
 152   /* stack has userdata, index */
 153   lua_pushvalue(L, 2);                     /* dup index */
 154   lua_rawget(L, lua_upvalueindex(1));      /* lookup member by name */
 155   if (!lua_islightuserdata(L, -1))
 156     {
 157       lua_pop(L, 1);                         /* drop value */
 158       lua_pushvalue(L, 2);                   /* dup index */
 159       lua_gettable(L, lua_upvalueindex(2));  /* else try methods */
 160       if (lua_isnil(L, -1))                  /* invalid member */
 161         luaL_error(L, "cannot get member '%s'", lua_tostring(L, 2));
 162       return 1;
 163     }
 164   return Xet_call(L);                      /* call get function */
 165 }
 166
 167 static int newindex_handler (lua_State *L)
 168 {
 169   /* stack has userdata, index, value */
 170   lua_pushvalue(L, 2);                     /* dup index */
 171   lua_rawget(L, lua_upvalueindex(1));      /* lookup member by name */
 172   if (!lua_islightuserdata(L, -1))         /* invalid member */
 173     luaL_error(L, "cannot set member '%s'", lua_tostring(L, 2));
 174   return Xet_call(L);                      /* call set function */
 175 }
 176
 177 static int
 178 struct_register(lua_State *L, const char *name, const luaL_reg fn_methods[], const luaL_reg meta_methods[],
 179     const struct Xet_reg setters[], const struct Xet_reg getters[])
 180 {
 181   int metatable, methods;
 182
 183   /* create methods table & add it to the table of globals */
 184   luaL_register(L, name, fn_methods);
 185   methods = lua_gettop(L);
 186
 187   /* create metatable & add it to the registry */
 188   luaL_newmetatable(L, name);
 189   luaL_register(L, 0, meta_methods);  /* fill metatable */
 190   metatable = lua_gettop(L);
 191
 192   lua_pushliteral(L, "__metatable");
 193   lua_pushvalue(L, methods);    /* dup methods table*/
 194   lua_rawset(L, metatable);     /* hide metatable:
 195                                    metatable.__metatable = methods */
 196
 197   lua_pushliteral(L, "__index");
 198   lua_pushvalue(L, metatable);  /* upvalue index 1 */
 199   Xet_add(L, getters);     /* fill metatable with getters */
 200   lua_pushvalue(L, methods);    /* upvalue index 2 */
 201   lua_pushcclosure(L, index_handler, 2);
 202   lua_rawset(L, metatable);     /* metatable.__index = index_handler */
 203
 204   lua_pushliteral(L, "__newindex");
 205   lua_newtable(L);              /* table for members you can set */
 206   Xet_add(L, setters);     /* fill with setters */
 207   lua_pushcclosure(L, newindex_handler, 1);
 208   lua_rawset(L, metatable);     /* metatable.__newindex = newindex_handler */
 209
 210   lua_pop(L, 1);                /* drop metatable */
 211   return 1;                     /* return methods on the stack */
 212 }
 213
 214 /** }}} */
 215
 216 /** Window {{{ */
 217
 218 PUSH_TYPE(window, struct win)
 219
 220 CHECK_TYPE(window, struct win)
 221
 222 static int get_window(lua_State *L, void *v)
 223 {
 224   push_window(L, *(struct win **)v);
 225   return 1;
 226 }
 227
 228 static int
 229 window_change_title(lua_State *L)
 230 {
 231   struct win *w = check_window(L, 1);
 232   unsigned int len;
 233   const char *title = luaL_checklstring(L, 2, &len);
 234   ChangeAKA(w, title, len);
 235   return 0;
 236 }
 237
 238 static const luaL_reg window_methods[] = {
 239   {"change_title", window_change_title},
 240   {0, 0}
 241 };
 242
 243 static int
 244 window_tostring(lua_State *L)
 245 {
 246   char str[128];
 247   struct win *w = check_window(L, 1);
 248   snprintf(str, sizeof(str), "{window #%d: '%s'}", w->w_number, w->w_title);
 249   lua_pushstring(L, str);
 250   return 1;
 251 }
 252
 253 static const luaL_reg window_metamethods[] = {
 254   {"__tostring", window_tostring},
 255   {0, 0}
 256 };
 257
 258 static const struct Xet_reg window_setters[] = {
 259   {0, 0}
 260 };
 261
 262 static const struct Xet_reg window_getters[] = {
 263   {"title", get_string, offsetof(struct win, w_title) + 8},
 264   {"number", get_int, offsetof(struct win, w_number)},
 265   {"dir", get_string, offsetof(struct win, w_dir)},
 266   {"tty", get_string, offsetof(struct win, w_tty)},
 267   {"pid", get_int, offsetof(struct win, w_pid)},
 268   {"group", get_window, offsetof(struct win, w_group)},
 269   {"bell", get_int, offsetof(struct win, w_bell)},
 270   {"monitor", get_int, offsetof(struct win, w_monitor)},
 271   {0, 0}
 272 };
 273
 274
 275 /** }}} */
 276
 277 /** AclUser {{{ */
 278
 279 PUSH_TYPE(user, struct acluser)
 280
 281 CHECK_TYPE(user, struct acluser)
 282
 283 static int
 284 get_user(lua_State *L, void *v)
 285 {
 286   push_user(L, *(struct acluser **)v);
 287   return 1;
 288 }
 289
 290 static const luaL_reg user_methods[] = {
 291   {0, 0}
 292 };
 293
 294 static int
 295 user_tostring(lua_State *L)
 296 {
 297   char str[128];
 298   struct acluser *u = check_user(L, 1);
 299   snprintf(str, sizeof(str), "{user '%s'}", u->u_name);
 300   lua_pushstring(L, str);
 301   return 1;
 302 }
 303
 304 static const luaL_reg user_metamethods[] = {
 305   {"__tostring", user_tostring},
 306   {0, 0}
 307 };
 308
 309 static const struct Xet_reg user_setters[] = {
 310   {0, 0}
 311 };
 312
 313 static const struct Xet_reg user_getters[] = {
 314   {"name", get_string, offsetof(struct acluser, u_name)},
 315   {"password", get_string, offsetof(struct acluser, u_password)},
 316   {0, 0}
 317 };
 318
 319 /** }}} */
 320
 321 /** Canvas {{{ */
 322
 323 PUSH_TYPE(canvas, struct canvas)
 324
 325 CHECK_TYPE(canvas, struct canvas)
 326
 327 static int
 328 get_canvas(lua_State *L, void *v)
 329 {
 330   push_canvas(L, *(struct canvas **)v);
 331   return 1;
 332 }
 333
 334 static int
 335 canvas_select(lua_State *L)
 336 {
 337   struct canvas *c = check_canvas(L, 1);
 338   if (!display || D_forecv == c)
 339     return 0;
 340   D_forecv = c;
 341
 342   /* XXX: the following all is duplicated from process.c:DoAction.
 343    * Should these be in some better place?
 344    */
 345   ResizeCanvas(&D_canvas);
 346   RecreateCanvasChain();
 347   RethinkDisplayViewports();
 348   ResizeLayersToCanvases();     /* redisplays */
 349   fore = D_fore = Layer2Window(D_forecv->c_layer);
 350   flayer = D_forecv->c_layer;
 351 #ifdef RXVT_OSC
 352   if (D_xtermosc[2] || D_xtermosc[3])
 353     {
 354       Activate(-1);
 355       break;
 356     }
 357 #endif
 358   RefreshHStatus();
 359 #ifdef RXVT_OSC
 360   RefreshXtermOSC();
 361 #endif
 362   flayer = D_forecv->c_layer;
 363   CV_CALL(D_forecv, LayRestore();LaySetCursor());
 364   WindowChanged(0, 'F');
 365 }
 366
 367 static const luaL_reg canvas_methods[] = {
 368   {"select", canvas_select},
 369   {0, 0}
 370 };
 371
 372 static const luaL_reg canvas_metamethods[] = {
 373   {0, 0}
 374 };
 375
 376 static const struct Xet_reg canvas_setters[] = {
 377   {0, 0}
 378 };
 379
 380 static int
 381 canvas_get_window(lua_State *L)
 382 {
 383   struct canvas *c = check_canvas(L, 1);
 384   struct win *win = Layer2Window(c->c_layer);
 385   if (win)
 386     push_window(L, win);
 387   else
 388     lua_pushnil(L);
 389   return 1;
 390 }
 391
 392 static const struct Xet_reg canvas_getters[] = {
 393   {"next", get_canvas, offsetof(struct canvas, c_next)},
 394   {"xoff", get_int, offsetof(struct canvas, c_xoff)},
 395   {"yoff", get_int, offsetof(struct canvas, c_yoff)},
 396   {"xs", get_int, offsetof(struct canvas, c_xs)},
 397   {"ys", get_int, offsetof(struct canvas, c_ys)},
 398   {"xe", get_int, offsetof(struct canvas, c_xe)},
 399   {"ye", get_int, offsetof(struct canvas, c_ye)},
 400   {"window", 0, 0, canvas_get_window},
 401   {0, 0}
 402 };
 403
 404 /** }}} */
 405
 406 /** Display {{{ */
 407
 408 PUSH_TYPE(display, struct display)
 409
 410 CHECK_TYPE(display, struct display)
 411
 412 static int
 413 display_get_canvases(lua_State *L)
 414 {
 415   struct display *d;
 416   struct canvas *iter;
 417   int count;
 418
 419   d = check_display(L, 1);
 420   for (iter = d->d_cvlist, count = 0; iter; iter = iter->c_next, count++)
 421     push_canvas(L, iter);
 422
 423   return count;
 424 }
 425
 426 static const luaL_reg display_methods[] = {
 427   {"get_canvases", display_get_canvases},
 428   {0, 0}
 429 };
 430
 431 static int
 432 display_tostring(lua_State *L)
 433 {
 434   char str[128];
 435   struct display *d = check_display(L, 1);
 436   snprintf(str, sizeof(str), "{display: tty = '%s', term = '%s'}", d->d_usertty, d->d_termname);
 437   lua_pushstring(L, str);
 438   return 1;
 439 }
 440
 441 static const luaL_reg display_metamethods[] = {
 442   {"__tostring", display_tostring},
 443   {0, 0}
 444 };
 445
 446 static const struct Xet_reg display_setters[] = {
 447   {0, 0}
 448 };
 449
 450 static const struct Xet_reg display_getters[] = {
 451   {"tty", get_string, offsetof(struct display, d_usertty)},
 452   {"term", get_string, offsetof(struct display, d_termname)},
 453   {"fore", get_window, offsetof(struct display, d_fore)},
 454   {"other", get_window, offsetof(struct display, d_other)},
 455   {"width", get_int, offsetof(struct display, d_width)},
 456   {"height", get_int, offsetof(struct display, d_height)},
 457   {"user", get_user, offsetof(struct display, d_user)},
 458   {0, 0}
 459 };
 460
 461 /** }}} */
 462
 463 /** Screen {{{ */
 464
 465 static int
 466 screen_get_windows(lua_State *L)
 467 {
 468   struct win *iter;
 469   int count;
 470
 471   for (iter = windows, count = 0; iter; iter = iter->w_next, count++)
 472     push_window(L, iter);
 473
 474   return count;
 475 }
 476
 477 static int
 478 screen_get_displays(lua_State *L)
 479 {
 480   struct display *iter;
 481   int count;
 482
 483   for (iter = displays, count = 0; iter; iter = iter->d_next, count++)
 484     push_display(L, iter);
 485
 486   return count;
 487 }
 488
 489 static int
 490 screen_get_display(lua_State *L)
 491 {
 492   push_display(L, display);
 493   return 1;
 494 }
 495
 496 static int
 497 screen_exec_command(lua_State *L)
 498 {
 499   const char *command;
 500   unsigned int len;
 501
 502   command = luaL_checklstring(L, 1, &len);
 503   if (command)
 504     RcLine(command, len);
 505
 506   return 0;
 507 }
 508
 509 static const luaL_reg screen_methods[] = {
 510   {"windows", screen_get_windows},
 511   {"displays", screen_get_displays},
 512   {"display", screen_get_display},
 513   {"command", screen_exec_command},
 514   {0, 0}
 515 };
 516
 517 static const luaL_reg screen_metamethods[] = {
 518   {0, 0}
 519 };
 520
 521 static const struct Xet_reg screen_setters[] = {
 522   {0, 0}
 523 };
 524
 525 static const struct Xet_reg screen_getters[] = {
 526   {0, 0}
 527 };
 528
 529 /** }}} */
 530
 531 /** Public functions {{{ */
 532 static lua_State *L;
 533 int LuaInit(void)
 534 {
 535   L = luaL_newstate();
 536
 537   luaL_openlibs(L);
 538
 539 #define REGISTER(X) struct_register(L, #X , X ## _methods, X##_metamethods, X##_setters, X##_getters)
 540
 541   REGISTER(screen);
 542   REGISTER(window);
 543   REGISTER(display);
 544   REGISTER(user);
 545   REGISTER(canvas);
 546
 547   return 0;
 548 }
 549
 550 int LuaForeWindowChanged(void)
 551 {
 552   if (!L)
 553     return 0;
 554   lua_getfield(L, LUA_GLOBALSINDEX, "fore_changed");
 555   if (lua_isnil(L, -1))
 556     return 0;
 557   push_display(L, display);
 558   push_window(L, display ? D_fore : fore);
 559   if (lua_pcall(L, 2, 0, 0) == LUA_ERRRUN)
 560     {
 561       if(lua_isstring(L, -1))
 562         {
 563           unsigned int len;
 564           char *message = luaL_checklstring(L, -1, &len);
 565           LMsg(1, "%s", message ? message : "Unknown error");
 566           lua_pop(L, 1);
 567         }
 568     }
 569   return 0;
 570 }
 571
 572 int LuaSource(const char *file)
 573 {
 574   if (!L)
 575     return 0;
 576   struct stat st;
 577   if (stat(file, &st) == -1)
 578     Msg(errno, "Error loading lua script file '%s'", file);
 579   else
 580     {
 581       int len = strlen(file);
 582       if (len < 4 || strncmp(file + len - 4, ".lua", 4) != 0)
 583         return 0;
 584       luaL_dofile(L, file);
 585       return 1;
 586     }
 587   return 0;
 588 }
 589
 590 int LuaFinit(void)
 591 {
 592   if (!L)
 593     return 0;
 594   lua_close(L);
 595   L = (lua_State*)0;
 596   return 0;
 597 }
 598
 599 int LuaCall(char **argv)
 600 {
 601   int argc;
 602   if (!L)
 603     return 0;
 604
 605   lua_getfield(L, LUA_GLOBALSINDEX, *argv);
 606   for (argc = 0, argv++; *argv; argv++, argc++)
 607     {
 608       lua_pushstring(L, *argv);
 609     }
 610   if (lua_pcall(L, argc, 0, 0) == LUA_ERRRUN)
 611     {
 612       if(lua_isstring(L, -1))
 613         {
 614           unsigned int len;
 615           char *message = luaL_checklstring(L, -1, &len);
 616           LMsg(1, "%s", message ? message : "Unknown error");
 617           lua_pop(L, 1);
 618           return 0;
 619         }
 620     }
 621   return 1;
 622 }
 623
 624
 625 /** }}} */
 626
 627 struct ScriptFuncs LuaFuncs =
 628 {
 629   LuaInit,
 630   LuaFinit,
 631   LuaForeWindowChanged,
 632   LuaSource
 633 };
 634