src/luajit.c

   1 /*
   2 ** LuaJIT frontend. Runs commands, scripts, read-eval-print (REPL) etc.
   3 ** Copyright (C) 2005-2023 Mike Pall. See Copyright Notice in luajit.h
   4 **
   5 ** Major portions taken verbatim or adapted from the Lua interpreter.
   6 ** Copyright (C) 1994-2008 Lua.org, PUC-Rio. See Copyright Notice in lua.h
   7 */
   8
   9 #include <stdio.h>
  10 #include <stdlib.h>
  11 #include <string.h>
  12
  13 #define luajit_c
  14
  15 #include "lua.h"
  16 #include "lauxlib.h"
  17 #include "lualib.h"
  18 #include "luajit.h"
  19
  20 #include "lj_arch.h"
  21
  22 #if LJ_TARGET_POSIX
  23 #include <unistd.h>
  24 #define lua_stdin_is_tty()      isatty(0)
  25 #elif LJ_TARGET_WINDOWS
  26 #include <io.h>
  27 #ifdef __BORLANDC__
  28 #define lua_stdin_is_tty()      isatty(_fileno(stdin))
  29 #else
  30 #define lua_stdin_is_tty()      _isatty(_fileno(stdin))
  31 #endif
  32 #else
  33 #define lua_stdin_is_tty()      1
  34 #endif
  35
  36 #if !LJ_TARGET_CONSOLE
  37 #include <signal.h>
  38 #endif
  39
  40 static lua_State *globalL = NULL;
  41 static const char *progname = LUA_PROGNAME;
  42 static char *empty_argv[2] = { NULL, NULL };
  43
  44 #if !LJ_TARGET_CONSOLE
  45 static void lstop(lua_State *L, lua_Debug *ar)
  46 {
  47   (void)ar;  /* unused arg. */
  48   lua_sethook(L, NULL, 0, 0);
  49   /* Avoid luaL_error -- a C hook doesn't add an extra frame. */
  50   luaL_where(L, 0);
  51   lua_pushfstring(L, "%sinterrupted!", lua_tostring(L, -1));
  52   lua_error(L);
  53 }
  54
  55 static void laction(int i)
  56 {
  57   signal(i, SIG_DFL); /* if another SIGINT happens before lstop,
  58                          terminate process (default action) */
  59   lua_sethook(globalL, lstop, LUA_MASKCALL | LUA_MASKRET | LUA_MASKCOUNT, 1);
  60 }
  61 #endif
  62
  63 static void print_usage(void)
  64 {
  65   fputs("usage: ", stderr);
  66   fputs(progname, stderr);
  67   fputs(" [options]... [script [args]...].\n"
  68   "Available options are:\n"
  69   "  -e chunk  Execute string " LUA_QL("chunk") ".\n"
  70   "  -l name   Require library " LUA_QL("name") ".\n"
  71   "  -b ...    Save or list bytecode.\n"
  72   "  -j cmd    Perform LuaJIT control command.\n"
  73   "  -O[opt]   Control LuaJIT optimizations.\n"
  74   "  -i        Enter interactive mode after executing " LUA_QL("script") ".\n"
  75   "  -v        Show version information.\n"
  76   "  -E        Ignore environment variables.\n"
  77   "  --        Stop handling options.\n"
  78   "  -         Execute stdin and stop handling options.\n", stderr);
  79   fflush(stderr);
  80 }
  81
  82 static void l_message(const char *msg)
  83 {
  84   if (progname) { fputs(progname, stderr); fputc(':', stderr); fputc(' ', stderr); }
  85   fputs(msg, stderr); fputc('\n', stderr);
  86   fflush(stderr);
  87 }
  88
  89 static int report(lua_State *L, int status)
  90 {
  91   if (status && !lua_isnil(L, -1)) {
  92     const char *msg = lua_tostring(L, -1);
  93     if (msg == NULL) msg = "(error object is not a string)";
  94     l_message(msg);
  95     lua_pop(L, 1);
  96   }
  97   return status;
  98 }
  99
 100 static int traceback(lua_State *L)
 101 {
 102   if (!lua_isstring(L, 1)) { /* Non-string error object? Try metamethod. */
 103     if (lua_isnoneornil(L, 1) ||
 104         !luaL_callmeta(L, 1, "__tostring") ||
 105         !lua_isstring(L, -1))
 106       return 1;  /* Return non-string error object. */
 107     lua_remove(L, 1);  /* Replace object by result of __tostring metamethod. */
 108   }
 109   luaL_traceback(L, L, lua_tostring(L, 1), 1);
 110   return 1;
 111 }
 112
 113 static int docall(lua_State *L, int narg, int clear)
 114 {
 115   int status;
 116   int base = lua_gettop(L) - narg;  /* function index */
 117   lua_pushcfunction(L, traceback);  /* push traceback function */
 118   lua_insert(L, base);  /* put it under chunk and args */
 119 #if !LJ_TARGET_CONSOLE
 120   signal(SIGINT, laction);
 121 #endif
 122   status = lua_pcall(L, narg, (clear ? 0 : LUA_MULTRET), base);
 123 #if !LJ_TARGET_CONSOLE
 124   signal(SIGINT, SIG_DFL);
 125 #endif
 126   lua_remove(L, base);  /* remove traceback function */
 127   /* force a complete garbage collection in case of errors */
 128   if (status != LUA_OK) lua_gc(L, LUA_GCCOLLECT, 0);
 129   return status;
 130 }
 131
 132 static void print_version(void)
 133 {
 134   fputs(LUAJIT_VERSION " -- " LUAJIT_COPYRIGHT ". " LUAJIT_URL "\n", stdout);
 135 }
 136
 137 static void print_jit_status(lua_State *L)
 138 {
 139   int n;
 140   const char *s;
 141   lua_getfield(L, LUA_REGISTRYINDEX, "_LOADED");
 142   lua_getfield(L, -1, "jit");  /* Get jit.* module table. */
 143   lua_remove(L, -2);
 144   lua_getfield(L, -1, "status");
 145   lua_remove(L, -2);
 146   n = lua_gettop(L);
 147   lua_call(L, 0, LUA_MULTRET);
 148   fputs(lua_toboolean(L, n) ? "JIT: ON" : "JIT: OFF", stdout);
 149   for (n++; (s = lua_tostring(L, n)); n++) {
 150     putc(' ', stdout);
 151     fputs(s, stdout);
 152   }
 153   putc('\n', stdout);
 154   lua_settop(L, 0);  /* clear stack */
 155 }
 156
 157 static void createargtable(lua_State *L, char **argv, int argc, int argf)
 158 {
 159   int i;
 160   lua_createtable(L, argc - argf, argf);
 161   for (i = 0; i < argc; i++) {
 162     lua_pushstring(L, argv[i]);
 163     lua_rawseti(L, -2, i - argf);
 164   }
 165   lua_setglobal(L, "arg");
 166 }
 167
 168 static int dofile(lua_State *L, const char *name)
 169 {
 170   int status = luaL_loadfile(L, name) || docall(L, 0, 1);
 171   return report(L, status);
 172 }
 173
 174 static int dostring(lua_State *L, const char *s, const char *name)
 175 {
 176   int status = luaL_loadbuffer(L, s, strlen(s), name) || docall(L, 0, 1);
 177   return report(L, status);
 178 }
 179
 180 static int dolibrary(lua_State *L, const char *name)
 181 {
 182   lua_getglobal(L, "require");
 183   lua_pushstring(L, name);
 184   return report(L, docall(L, 1, 1));
 185 }
 186
 187 static void write_prompt(lua_State *L, int firstline)
 188 {
 189   const char *p;
 190   lua_getfield(L, LUA_GLOBALSINDEX, firstline ? "_PROMPT" : "_PROMPT2");
 191   p = lua_tostring(L, -1);
 192   if (p == NULL) p = firstline ? LUA_PROMPT : LUA_PROMPT2;
 193   fputs(p, stdout);
 194   fflush(stdout);
 195   lua_pop(L, 1);  /* remove global */
 196 }
 197
 198 static int incomplete(lua_State *L, int status)
 199 {
 200   if (status == LUA_ERRSYNTAX) {
 201     size_t lmsg;
 202     const char *msg = lua_tolstring(L, -1, &lmsg);
 203     const char *tp = msg + lmsg - (sizeof(LUA_QL("<eof>")) - 1);
 204     if (strstr(msg, LUA_QL("<eof>")) == tp) {
 205       lua_pop(L, 1);
 206       return 1;
 207     }
 208   }
 209   return 0;  /* else... */
 210 }
 211
 212 static int pushline(lua_State *L, int firstline)
 213 {
 214   char buf[LUA_MAXINPUT];
 215   write_prompt(L, firstline);
 216   if (fgets(buf, LUA_MAXINPUT, stdin)) {
 217     size_t len = strlen(buf);
 218     if (len > 0 && buf[len-1] == '\n')
 219       buf[len-1] = '\0';
 220     if (firstline && buf[0] == '=')
 221       lua_pushfstring(L, "return %s", buf+1);
 222     else
 223       lua_pushstring(L, buf);
 224     return 1;
 225   }
 226   return 0;
 227 }
 228
 229 static int loadline(lua_State *L)
 230 {
 231   int status;
 232   lua_settop(L, 0);
 233   if (!pushline(L, 1))
 234     return -1;  /* no input */
 235   for (;;) {  /* repeat until gets a complete line */
 236     status = luaL_loadbuffer(L, lua_tostring(L, 1), lua_strlen(L, 1), "=stdin");
 237     if (!incomplete(L, status)) break;  /* cannot try to add lines? */
 238     if (!pushline(L, 0))  /* no more input? */
 239       return -1;
 240     lua_pushliteral(L, "\n");  /* add a new line... */
 241     lua_insert(L, -2);  /* ...between the two lines */
 242     lua_concat(L, 3);  /* join them */
 243   }
 244   lua_remove(L, 1);  /* remove line */
 245   return status;
 246 }
 247
 248 static void dotty(lua_State *L)
 249 {
 250   int status;
 251   const char *oldprogname = progname;
 252   progname = NULL;
 253   while ((status = loadline(L)) != -1) {
 254     if (status == LUA_OK) status = docall(L, 0, 0);
 255     report(L, status);
 256     if (status == LUA_OK && lua_gettop(L) > 0) {  /* any result to print? */
 257       lua_getglobal(L, "print");
 258       lua_insert(L, 1);
 259       if (lua_pcall(L, lua_gettop(L)-1, 0, 0) != 0)
 260         l_message(lua_pushfstring(L, "error calling " LUA_QL("print") " (%s)",
 261                                   lua_tostring(L, -1)));
 262     }
 263   }
 264   lua_settop(L, 0);  /* clear stack */
 265   fputs("\n", stdout);
 266   fflush(stdout);
 267   progname = oldprogname;
 268 }
 269
 270 static int handle_script(lua_State *L, char **argx)
 271 {
 272   int status;
 273   const char *fname = argx[0];
 274   if (strcmp(fname, "-") == 0 && strcmp(argx[-1], "--") != 0)
 275     fname = NULL;  /* stdin */
 276   status = luaL_loadfile(L, fname);
 277   if (status == LUA_OK) {
 278     /* Fetch args from arg table. LUA_INIT or -e might have changed them. */
 279     int narg = 0;
 280     lua_getglobal(L, "arg");
 281     if (lua_istable(L, -1)) {
 282       do {
 283         narg++;
 284         lua_rawgeti(L, -narg, narg);
 285       } while (!lua_isnil(L, -1));
 286       lua_pop(L, 1);
 287       lua_remove(L, -narg);
 288       narg--;
 289     } else {
 290       lua_pop(L, 1);
 291     }
 292     status = docall(L, narg, 0);
 293   }
 294   return report(L, status);
 295 }
 296
 297 /* Load add-on module. */
 298 static int loadjitmodule(lua_State *L)
 299 {
 300   lua_getglobal(L, "require");
 301   lua_pushliteral(L, "jit.");
 302   lua_pushvalue(L, -3);
 303   lua_concat(L, 2);
 304   if (lua_pcall(L, 1, 1, 0)) {
 305     const char *msg = lua_tostring(L, -1);
 306     if (msg && !strncmp(msg, "module ", 7))
 307       goto nomodule;
 308     return report(L, 1);
 309   }
 310   lua_getfield(L, -1, "start");
 311   if (lua_isnil(L, -1)) {
 312   nomodule:
 313     l_message("unknown luaJIT command or jit.* modules not installed");
 314     return 1;
 315   }
 316   lua_remove(L, -2);  /* Drop module table. */
 317   return 0;
 318 }
 319
 320 /* Run command with options. */
 321 static int runcmdopt(lua_State *L, const char *opt)
 322 {
 323   int narg = 0;
 324   if (opt && *opt) {
 325     for (;;) {  /* Split arguments. */
 326       const char *p = strchr(opt, ',');
 327       narg++;
 328       if (!p) break;
 329       if (p == opt)
 330         lua_pushnil(L);
 331       else
 332         lua_pushlstring(L, opt, (size_t)(p - opt));
 333       opt = p + 1;
 334     }
 335     if (*opt)
 336       lua_pushstring(L, opt);
 337     else
 338       lua_pushnil(L);
 339   }
 340   return report(L, lua_pcall(L, narg, 0, 0));
 341 }
 342
 343 /* JIT engine control command: try jit library first or load add-on module. */
 344 static int dojitcmd(lua_State *L, const char *cmd)
 345 {
 346   const char *opt = strchr(cmd, '=');
 347   lua_pushlstring(L, cmd, opt ? (size_t)(opt - cmd) : strlen(cmd));
 348   lua_getfield(L, LUA_REGISTRYINDEX, "_LOADED");
 349   lua_getfield(L, -1, "jit");  /* Get jit.* module table. */
 350   lua_remove(L, -2);
 351   lua_pushvalue(L, -2);
 352   lua_gettable(L, -2);  /* Lookup library function. */
 353   if (!lua_isfunction(L, -1)) {
 354     lua_pop(L, 2);  /* Drop non-function and jit.* table, keep module name. */
 355     if (loadjitmodule(L))
 356       return 1;
 357   } else {
 358     lua_remove(L, -2);  /* Drop jit.* table. */
 359   }
 360   lua_remove(L, -2);  /* Drop module name. */
 361   return runcmdopt(L, opt ? opt+1 : opt);
 362 }
 363
 364 /* Optimization flags. */
 365 static int dojitopt(lua_State *L, const char *opt)
 366 {
 367   lua_getfield(L, LUA_REGISTRYINDEX, "_LOADED");
 368   lua_getfield(L, -1, "jit.opt");  /* Get jit.opt.* module table. */
 369   lua_remove(L, -2);
 370   lua_getfield(L, -1, "start");
 371   lua_remove(L, -2);
 372   return runcmdopt(L, opt);
 373 }
 374
 375 /* Save or list bytecode. */
 376 static int dobytecode(lua_State *L, char **argv)
 377 {
 378   int narg = 0;
 379   lua_pushliteral(L, "bcsave");
 380   if (loadjitmodule(L))
 381     return 1;
 382   if (argv[0][2]) {
 383     narg++;
 384     argv[0][1] = '-';
 385     lua_pushstring(L, argv[0]+1);
 386   }
 387   for (argv++; *argv != NULL; narg++, argv++)
 388     lua_pushstring(L, *argv);
 389   report(L, lua_pcall(L, narg, 0, 0));
 390   return -1;
 391 }
 392
 393 /* check that argument has no extra characters at the end */
 394 #define notail(x)       {if ((x)[2] != '\0') return -1;}
 395
 396 #define FLAGS_INTERACTIVE       1
 397 #define FLAGS_VERSION           2
 398 #define FLAGS_EXEC              4
 399 #define FLAGS_OPTION            8
 400 #define FLAGS_NOENV             16
 401
 402 static int collectargs(char **argv, int *flags)
 403 {
 404   int i;
 405   for (i = 1; argv[i] != NULL; i++) {
 406     if (argv[i][0] != '-')  /* Not an option? */
 407       return i;
 408     switch (argv[i][1]) {  /* Check option. */
 409     case '-':
 410       notail(argv[i]);
 411       return i+1;
 412     case '\0':
 413       return i;
 414     case 'i':
 415       notail(argv[i]);
 416       *flags |= FLAGS_INTERACTIVE;
 417       /* fallthrough */
 418     case 'v':
 419       notail(argv[i]);
 420       *flags |= FLAGS_VERSION;
 421       break;
 422     case 'e':
 423       *flags |= FLAGS_EXEC;
 424       /* fallthrough */
 425     case 'j':  /* LuaJIT extension */
 426     case 'l':
 427       *flags |= FLAGS_OPTION;
 428       if (argv[i][2] == '\0') {
 429         i++;
 430         if (argv[i] == NULL) return -1;
 431       }
 432       break;
 433     case 'O': break;  /* LuaJIT extension */
 434     case 'b':  /* LuaJIT extension */
 435       if (*flags) return -1;
 436       *flags |= FLAGS_EXEC;
 437       return i+1;
 438     case 'E':
 439       *flags |= FLAGS_NOENV;
 440       break;
 441     default: return -1;  /* invalid option */
 442     }
 443   }
 444   return i;
 445 }
 446
 447 static int runargs(lua_State *L, char **argv, int argn)
 448 {
 449   int i;
 450   for (i = 1; i < argn; i++) {
 451     if (argv[i] == NULL) continue;
 452     lua_assert(argv[i][0] == '-');
 453     switch (argv[i][1]) {
 454     case 'e': {
 455       const char *chunk = argv[i] + 2;
 456       if (*chunk == '\0') chunk = argv[++i];
 457       lua_assert(chunk != NULL);
 458       if (dostring(L, chunk, "=(command line)") != 0)
 459         return 1;
 460       break;
 461       }
 462     case 'l': {
 463       const char *filename = argv[i] + 2;
 464       if (*filename == '\0') filename = argv[++i];
 465       lua_assert(filename != NULL);
 466       if (dolibrary(L, filename))
 467         return 1;
 468       break;
 469       }
 470     case 'j': {  /* LuaJIT extension. */
 471       const char *cmd = argv[i] + 2;
 472       if (*cmd == '\0') cmd = argv[++i];
 473       lua_assert(cmd != NULL);
 474       if (dojitcmd(L, cmd))
 475         return 1;
 476       break;
 477       }
 478     case 'O':  /* LuaJIT extension. */
 479       if (dojitopt(L, argv[i] + 2))
 480         return 1;
 481       break;
 482     case 'b':  /* LuaJIT extension. */
 483       return dobytecode(L, argv+i);
 484     default: break;
 485     }
 486   }
 487   return LUA_OK;
 488 }
 489
 490 static int handle_luainit(lua_State *L)
 491 {
 492 #if LJ_TARGET_CONSOLE
 493   const char *init = NULL;
 494 #else
 495   const char *init = getenv(LUA_INIT);
 496 #endif
 497   if (init == NULL)
 498     return LUA_OK;
 499   else if (init[0] == '@')
 500     return dofile(L, init+1);
 501   else
 502     return dostring(L, init, "=" LUA_INIT);
 503 }
 504
 505 static struct Smain {
 506   char **argv;
 507   int argc;
 508   int status;
 509 } smain;
 510
 511 static int pmain(lua_State *L)
 512 {
 513   struct Smain *s = &smain;
 514   char **argv = s->argv;
 515   int argn;
 516   int flags = 0;
 517   globalL = L;
 518   LUAJIT_VERSION_SYM();  /* Linker-enforced version check. */
 519
 520   argn = collectargs(argv, &flags);
 521   if (argn < 0) {  /* Invalid args? */
 522     print_usage();
 523     s->status = 1;
 524     return 0;
 525   }
 526
 527   if ((flags & FLAGS_NOENV)) {
 528     lua_pushboolean(L, 1);
 529     lua_setfield(L, LUA_REGISTRYINDEX, "LUA_NOENV");
 530   }
 531
 532   /* Stop collector during library initialization. */
 533   lua_gc(L, LUA_GCSTOP, 0);
 534   luaL_openlibs(L);
 535   lua_gc(L, LUA_GCRESTART, -1);
 536
 537   createargtable(L, argv, s->argc, argn);
 538
 539   if (!(flags & FLAGS_NOENV)) {
 540     s->status = handle_luainit(L);
 541     if (s->status != LUA_OK) return 0;
 542   }
 543
 544   if ((flags & FLAGS_VERSION)) print_version();
 545
 546   s->status = runargs(L, argv, argn);
 547   if (s->status != LUA_OK) return 0;
 548
 549   if (s->argc > argn) {
 550     s->status = handle_script(L, argv + argn);
 551     if (s->status != LUA_OK) return 0;
 552   }
 553
 554   if ((flags & FLAGS_INTERACTIVE)) {
 555     print_jit_status(L);
 556     dotty(L);
 557   } else if (s->argc == argn && !(flags & (FLAGS_EXEC|FLAGS_VERSION))) {
 558     if (lua_stdin_is_tty()) {
 559       print_version();
 560       print_jit_status(L);
 561       dotty(L);
 562     } else {
 563       dofile(L, NULL);  /* Executes stdin as a file. */
 564     }
 565   }
 566   return 0;
 567 }
 568
 569 int main(int argc, char **argv)
 570 {
 571   int status;
 572   lua_State *L;
 573   if (!argv[0]) argv = empty_argv; else if (argv[0][0]) progname = argv[0];
 574   L = lua_open();
 575   if (L == NULL) {
 576     l_message("cannot create state: not enough memory");
 577     return EXIT_FAILURE;
 578   }
 579   smain.argc = argc;
 580   smain.argv = argv;
 581   status = lua_cpcall(L, pmain, NULL);
 582   report(L, status);
 583   lua_close(L);
 584   return (status || smain.status > 0) ? EXIT_FAILURE : EXIT_SUCCESS;
 585 }
 586