1 /* 2 ** $Id: lua.c,v 1.206.1.1 2013/04/12 18:48:47 roberto Exp $ 3 ** Lua stand-alone interpreter 4 ** See Copyright Notice in lua.h 5 */ 6 7 8 #ifdef SYSLINUX 9 #include <console.h> 10 #define signal(x,y) 11 #else 12 #include <signal.h> 13 #endif 14 #include <stdio.h> 15 #include <stdlib.h> 16 #include <string.h> 17 18 #define lua_c 19 20 #include "lua.h" 21 22 #include "lauxlib.h" 23 #include "lualib.h" 24 25 26 #if !defined(LUA_PROMPT) 27 #define LUA_PROMPT "> " 28 #define LUA_PROMPT2 ">> " 29 #endif 30 31 #if !defined(LUA_PROGNAME) 32 #define LUA_PROGNAME "lua" 33 #endif 34 35 #if !defined(LUA_MAXINPUT) 36 #define LUA_MAXINPUT 512 37 #endif 38 39 #if !defined(LUA_INIT) 40 #define LUA_INIT "LUA_INIT" 41 #endif 42 43 #define LUA_INITVERSION \ 44 LUA_INIT "_" LUA_VERSION_MAJOR "_" LUA_VERSION_MINOR 45 46 47 /* 48 ** lua_stdin_is_tty detects whether the standard input is a 'tty' (that 49 ** is, whether we're running lua interactively). 50 */ 51 #if defined(LUA_USE_ISATTY) 52 #include <unistd.h> 53 #define lua_stdin_is_tty() isatty(0) 54 #elif defined(LUA_WIN) 55 #include <io.h> 56 #include <stdio.h> 57 #define lua_stdin_is_tty() _isatty(_fileno(stdin)) 58 #else 59 #define lua_stdin_is_tty() 1 /* assume stdin is a tty */ 60 #endif 61 62 63 /* 64 ** lua_readline defines how to show a prompt and then read a line from 65 ** the standard input. 66 ** lua_saveline defines how to "save" a read line in a "history". 67 ** lua_freeline defines how to free a line read by lua_readline. 68 */ 69 #if defined(LUA_USE_READLINE) 70 71 #include <stdio.h> 72 #include <readline/readline.h> 73 #include <readline/history.h> 74 #define lua_readline(L,b,p) ((void)L, ((b)=readline(p)) != NULL) 75 #define lua_saveline(L,idx) \ 76 if (lua_rawlen(L,idx) > 0) /* non-empty line? */ \ 77 add_history(lua_tostring(L, idx)); /* add it to history */ 78 #define lua_freeline(L,b) ((void)L, free(b)) 79 80 #elif !defined(lua_readline) 81 82 #define lua_readline(L,b,p) \ 83 ((void)L, fputs(p, stdout), fflush(stdout), /* show prompt */ \ 84 fgets(b, LUA_MAXINPUT, stdin) != NULL) /* get line */ 85 #define lua_saveline(L,idx) { (void)L; (void)idx; } 86 #define lua_freeline(L,b) { (void)L; (void)b; } 87 88 #endif 89 90 91 92 93 static lua_State *globalL = NULL; 94 95 static const char *progname = LUA_PROGNAME; 96 97 98 99 #ifndef SYSLINUX 100 static void lstop (lua_State *L, lua_Debug *ar) { 101 (void)ar; /* unused arg. */ 102 lua_sethook(L, NULL, 0, 0); 103 luaL_error(L, "interrupted!"); 104 } 105 106 107 static void laction (int i) { 108 signal(i, SIG_DFL); /* if another SIGINT happens before lstop, 109 terminate process (default action) */ 110 lua_sethook(globalL, lstop, LUA_MASKCALL | LUA_MASKRET | LUA_MASKCOUNT, 1); 111 } 112 #endif 113 114 115 static void print_usage (const char *badoption) { 116 luai_writestringerror("%s: ", progname); 117 if (badoption[1] == 'e' || badoption[1] == 'l') 118 luai_writestringerror("'%s' needs argument\n", badoption); 119 else 120 luai_writestringerror("unrecognized option '%s'\n", badoption); 121 luai_writestringerror( 122 "usage: %s [options] [script [args]]\n" 123 "Available options are:\n" 124 " -e stat execute string " LUA_QL("stat") "\n" 125 " -i enter interactive mode after executing " LUA_QL("script") "\n" 126 " -l name require library " LUA_QL("name") "\n" 127 " -v show version information\n" 128 " -E ignore environment variables\n" 129 " -- stop handling options\n" 130 " - stop handling options and execute stdin\n" 131 , 132 progname); 133 } 134 135 136 static void l_message (const char *pname, const char *msg) { 137 if (pname) luai_writestringerror("%s: ", pname); 138 luai_writestringerror("%s\n", msg); 139 } 140 141 142 static int report (lua_State *L, int status) { 143 if (status != LUA_OK && !lua_isnil(L, -1)) { 144 const char *msg = lua_tostring(L, -1); 145 if (msg == NULL) msg = "(error object is not a string)"; 146 l_message(progname, msg); 147 lua_pop(L, 1); 148 /* force a complete garbage collection in case of errors */ 149 lua_gc(L, LUA_GCCOLLECT, 0); 150 } 151 return status; 152 } 153 154 155 /* the next function is called unprotected, so it must avoid errors */ 156 static void finalreport (lua_State *L, int status) { 157 if (status != LUA_OK) { 158 const char *msg = (lua_type(L, -1) == LUA_TSTRING) ? lua_tostring(L, -1) 159 : NULL; 160 if (msg == NULL) msg = "(error object is not a string)"; 161 l_message(progname, msg); 162 lua_pop(L, 1); 163 } 164 } 165 166 167 static int traceback (lua_State *L) { 168 const char *msg = lua_tostring(L, 1); 169 if (msg) 170 luaL_traceback(L, L, msg, 1); 171 else if (!lua_isnoneornil(L, 1)) { /* is there an error object? */ 172 if (!luaL_callmeta(L, 1, "__tostring")) /* try its 'tostring' metamethod */ 173 lua_pushliteral(L, "(no error message)"); 174 } 175 return 1; 176 } 177 178 179 static int docall (lua_State *L, int narg, int nres) { 180 int status; 181 int base = lua_gettop(L) - narg; /* function index */ 182 lua_pushcfunction(L, traceback); /* push traceback function */ 183 lua_insert(L, base); /* put it under chunk and args */ 184 globalL = L; /* to be available to 'laction' */ 185 signal(SIGINT, laction); 186 status = lua_pcall(L, narg, nres, base); 187 signal(SIGINT, SIG_DFL); 188 lua_remove(L, base); /* remove traceback function */ 189 return status; 190 } 191 192 193 static void print_version (void) { 194 luai_writestring(LUA_COPYRIGHT, strlen(LUA_COPYRIGHT)); 195 luai_writeline(); 196 } 197 198 199 static int getargs (lua_State *L, char **argv, int n) { 200 int narg; 201 int i; 202 int argc = 0; 203 while (argv[argc]) argc++; /* count total number of arguments */ 204 narg = argc - (n + 1); /* number of arguments to the script */ 205 luaL_checkstack(L, narg + 3, "too many arguments to script"); 206 for (i=n+1; i < argc; i++) 207 lua_pushstring(L, argv[i]); 208 lua_createtable(L, narg, n + 1); 209 for (i=0; i < argc; i++) { 210 lua_pushstring(L, argv[i]); 211 lua_rawseti(L, -2, i - n); 212 } 213 return narg; 214 } 215 216 217 static int dofile (lua_State *L, const char *name) { 218 int status = luaL_loadfile(L, name); 219 if (status == LUA_OK) status = docall(L, 0, 0); 220 return report(L, status); 221 } 222 223 224 static int dostring (lua_State *L, const char *s, const char *name) { 225 int status = luaL_loadbuffer(L, s, strlen(s), name); 226 if (status == LUA_OK) status = docall(L, 0, 0); 227 return report(L, status); 228 } 229 230 231 static int dolibrary (lua_State *L, const char *name) { 232 int status; 233 lua_getglobal(L, "require"); 234 lua_pushstring(L, name); 235 status = docall(L, 1, 1); /* call 'require(name)' */ 236 if (status == LUA_OK) 237 lua_setglobal(L, name); /* global[name] = require return */ 238 return report(L, status); 239 } 240 241 242 static const char *get_prompt (lua_State *L, int firstline) { 243 const char *p; 244 lua_getglobal(L, firstline ? "_PROMPT" : "_PROMPT2"); 245 p = lua_tostring(L, -1); 246 if (p == NULL) p = (firstline ? LUA_PROMPT : LUA_PROMPT2); 247 return p; 248 } 249 250 /* mark in error messages for incomplete statements */ 251 #define EOFMARK "<eof>" 252 #define marklen (sizeof(EOFMARK)/sizeof(char) - 1) 253 254 static int incomplete (lua_State *L, int status) { 255 if (status == LUA_ERRSYNTAX) { 256 size_t lmsg; 257 const char *msg = lua_tolstring(L, -1, &lmsg); 258 if (lmsg >= marklen && strcmp(msg + lmsg - marklen, EOFMARK) == 0) { 259 lua_pop(L, 1); 260 return 1; 261 } 262 } 263 return 0; /* else... */ 264 } 265 266 267 static int pushline (lua_State *L, int firstline) { 268 char buffer[LUA_MAXINPUT]; 269 char *b = buffer; 270 size_t l; 271 const char *prmt = get_prompt(L, firstline); 272 int readstatus = lua_readline(L, b, prmt); 273 lua_pop(L, 1); /* remove result from 'get_prompt' */ 274 if (readstatus == 0) 275 return 0; /* no input */ 276 l = strlen(b); 277 if (l > 0 && b[l-1] == '\n') /* line ends with newline? */ 278 b[l-1] = '\0'; /* remove it */ 279 if (firstline && b[0] == '=') /* first line starts with `=' ? */ 280 lua_pushfstring(L, "return %s", b+1); /* change it to `return' */ 281 else 282 lua_pushstring(L, b); 283 lua_freeline(L, b); 284 return 1; 285 } 286 287 288 static int loadline (lua_State *L) { 289 int status; 290 lua_settop(L, 0); 291 if (!pushline(L, 1)) 292 return -1; /* no input */ 293 for (;;) { /* repeat until gets a complete line */ 294 size_t l; 295 const char *line = lua_tolstring(L, 1, &l); 296 status = luaL_loadbuffer(L, line, l, "=stdin"); 297 if (!incomplete(L, status)) break; /* cannot try to add lines? */ 298 if (!pushline(L, 0)) /* no more input? */ 299 return -1; 300 lua_pushliteral(L, "\n"); /* add a new line... */ 301 lua_insert(L, -2); /* ...between the two lines */ 302 lua_concat(L, 3); /* join them */ 303 } 304 lua_saveline(L, 1); 305 lua_remove(L, 1); /* remove line */ 306 return status; 307 } 308 309 310 static void dotty (lua_State *L) { 311 int status; 312 const char *oldprogname = progname; 313 progname = NULL; 314 while ((status = loadline(L)) != -1) { 315 if (status == LUA_OK) status = docall(L, 0, LUA_MULTRET); 316 report(L, status); 317 if (status == LUA_OK && lua_gettop(L) > 0) { /* any result to print? */ 318 luaL_checkstack(L, LUA_MINSTACK, "too many results to print"); 319 lua_getglobal(L, "print"); 320 lua_insert(L, 1); 321 if (lua_pcall(L, lua_gettop(L)-1, 0, 0) != LUA_OK) 322 l_message(progname, lua_pushfstring(L, 323 "error calling " LUA_QL("print") " (%s)", 324 lua_tostring(L, -1))); 325 } 326 } 327 lua_settop(L, 0); /* clear stack */ 328 luai_writeline(); 329 progname = oldprogname; 330 } 331 332 333 static int handle_script (lua_State *L, char **argv, int n) { 334 int status; 335 const char *fname; 336 int narg = getargs(L, argv, n); /* collect arguments */ 337 lua_setglobal(L, "arg"); 338 fname = argv[n]; 339 if (strcmp(fname, "-") == 0 && strcmp(argv[n-1], "--") != 0) 340 fname = NULL; /* stdin */ 341 status = luaL_loadfile(L, fname); 342 lua_insert(L, -(narg+1)); 343 if (status == LUA_OK) 344 status = docall(L, narg, LUA_MULTRET); 345 else 346 lua_pop(L, narg); 347 return report(L, status); 348 } 349 350 351 /* check that argument has no extra characters at the end */ 352 #define noextrachars(x) {if ((x)[2] != '\0') return -1;} 353 354 355 /* indices of various argument indicators in array args */ 356 #define has_i 0 /* -i */ 357 #define has_v 1 /* -v */ 358 #define has_e 2 /* -e */ 359 #define has_E 3 /* -E */ 360 361 #define num_has 4 /* number of 'has_*' */ 362 363 364 static int collectargs (char **argv, int *args) { 365 int i; 366 for (i = 1; argv[i] != NULL; i++) { 367 if (argv[i][0] != '-') /* not an option? */ 368 return i; 369 switch (argv[i][1]) { /* option */ 370 case '-': 371 noextrachars(argv[i]); 372 return (argv[i+1] != NULL ? i+1 : 0); 373 case '\0': 374 return i; 375 case 'E': 376 args[has_E] = 1; 377 break; 378 case 'i': 379 noextrachars(argv[i]); 380 args[has_i] = 1; /* go through */ 381 case 'v': 382 noextrachars(argv[i]); 383 args[has_v] = 1; 384 break; 385 case 'e': 386 args[has_e] = 1; /* go through */ 387 case 'l': /* both options need an argument */ 388 if (argv[i][2] == '\0') { /* no concatenated argument? */ 389 i++; /* try next 'argv' */ 390 if (argv[i] == NULL || argv[i][0] == '-') 391 return -(i - 1); /* no next argument or it is another option */ 392 } 393 break; 394 default: /* invalid option; return its index... */ 395 return -i; /* ...as a negative value */ 396 } 397 } 398 return 0; 399 } 400 401 402 static int runargs (lua_State *L, char **argv, int n) { 403 int i; 404 for (i = 1; i < n; i++) { 405 lua_assert(argv[i][0] == '-'); 406 switch (argv[i][1]) { /* option */ 407 case 'e': { 408 const char *chunk = argv[i] + 2; 409 if (*chunk == '\0') chunk = argv[++i]; 410 lua_assert(chunk != NULL); 411 if (dostring(L, chunk, "=(command line)") != LUA_OK) 412 return 0; 413 break; 414 } 415 case 'l': { 416 const char *filename = argv[i] + 2; 417 if (*filename == '\0') filename = argv[++i]; 418 lua_assert(filename != NULL); 419 if (dolibrary(L, filename) != LUA_OK) 420 return 0; /* stop if file fails */ 421 break; 422 } 423 default: break; 424 } 425 } 426 return 1; 427 } 428 429 430 static int handle_luainit (lua_State *L) { 431 const char *name = "=" LUA_INITVERSION; 432 const char *init = getenv(name + 1); 433 if (init == NULL) { 434 name = "=" LUA_INIT; 435 init = getenv(name + 1); /* try alternative name */ 436 } 437 if (init == NULL) return LUA_OK; 438 else if (init[0] == '@') 439 return dofile(L, init+1); 440 else 441 return dostring(L, init, name); 442 } 443 444 445 static int pmain (lua_State *L) { 446 int argc = (int)lua_tointeger(L, 1); 447 char **argv = (char **)lua_touserdata(L, 2); 448 int script; 449 int args[num_has]; 450 args[has_i] = args[has_v] = args[has_e] = args[has_E] = 0; 451 if (argv[0] && argv[0][0]) progname = argv[0]; 452 script = collectargs(argv, args); 453 if (script < 0) { /* invalid arg? */ 454 print_usage(argv[-script]); 455 return 0; 456 } 457 if (args[has_v]) print_version(); 458 if (args[has_E]) { /* option '-E'? */ 459 lua_pushboolean(L, 1); /* signal for libraries to ignore env. vars. */ 460 lua_setfield(L, LUA_REGISTRYINDEX, "LUA_NOENV"); 461 } 462 /* open standard libraries */ 463 luaL_checkversion(L); 464 lua_gc(L, LUA_GCSTOP, 0); /* stop collector during initialization */ 465 luaL_openlibs(L); /* open libraries */ 466 lua_gc(L, LUA_GCRESTART, 0); 467 if (!args[has_E] && handle_luainit(L) != LUA_OK) 468 return 0; /* error running LUA_INIT */ 469 /* execute arguments -e and -l */ 470 if (!runargs(L, argv, (script > 0) ? script : argc)) return 0; 471 /* execute main script (if there is one) */ 472 if (script && handle_script(L, argv, script) != LUA_OK) return 0; 473 if (args[has_i]) /* -i option? */ 474 dotty(L); 475 else if (script == 0 && !args[has_e] && !args[has_v]) { /* no arguments? */ 476 if (lua_stdin_is_tty()) { 477 print_version(); 478 dotty(L); 479 } 480 else dofile(L, NULL); /* executes stdin as a file */ 481 } 482 lua_pushboolean(L, 1); /* signal no errors */ 483 return 1; 484 } 485 486 487 int main (int argc, char **argv) { 488 int status, result; 489 lua_State *L = luaL_newstate(); /* create state */ 490 if (L == NULL) { 491 l_message(argv[0], "cannot create state: not enough memory"); 492 return EXIT_FAILURE; 493 } 494 #ifdef SYSLINUX 495 openconsole(&dev_stdcon_r, &dev_stdcon_w); 496 #endif 497 /* call 'pmain' in protected mode */ 498 lua_pushcfunction(L, &pmain); 499 lua_pushinteger(L, argc); /* 1st argument */ 500 lua_pushlightuserdata(L, argv); /* 2nd argument */ 501 status = lua_pcall(L, 2, 1, 0); 502 result = lua_toboolean(L, -1); /* get result */ 503 finalreport(L, status); 504 lua_close(L); 505 return (result && status == LUA_OK) ? EXIT_SUCCESS : EXIT_FAILURE; 506 } 507 508
