src/luajit.c

   1 /*
   2 ** LuaJIT frontend. Runs commands, scripts, read-eval-print (REPL) etc.
   3 ** Copyright (C) 2005-2017 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
  43 #if !LJ_TARGET_CONSOLE
  44 static void lstop(lua_State *L, lua_Debug *ar)
  45 {
  46   (void)ar;  /* unused arg. */
  47   lua_sethook(L, NULL, 0, 0);
  48   /* Avoid luaL_error -- a C hook doesn't add an extra frame. */
  49   luaL_where(L, 0);
  50   lua_pushfstring(L, "%sinterrupted!", lua_tostring(L, -1));
  51   lua_error(L);
  52 }
  53
  54 static void laction(int i)
  55 {
  56   signal(i, SIG_DFL); /* if another SIGINT happens before lstop,
  57                          terminate process (default action) */
  58   lua_sethook(globalL, lstop, LUA_MASKCALL | LUA_MASKRET | LUA_MASKCOUNT, 1);
  59 }
  60 #endif
  61
  62 static void print_usage(void)
  63 {
  64   fprintf(stderr,
  65   "usage: %s [options]... [script [args]...].\n"
  66   "Available options are:\n"
  67   "  -e chunk  Execute string " LUA_QL("chunk") ".\n"
  68   "  -l name   Require library " LUA_QL("name") ".\n"
  69   "  -b ...    Save or list bytecode.\n"
  70   "  -j cmd    Perform LuaJIT control command.\n"
  71   "  -O[opt]   Control LuaJIT optimizations.\n"
  72   "  -i        Enter interactive mode after executing " LUA_QL("script") ".\n"
  73   "  -v        Show version information.\n"
  74   "  -E        Ignore environment variables.\n"
  75   "  --        Stop handling options.\n"
  76   "  -         Execute stdin and stop handling options.\n"
  77   ,
  78   progname);
  79   fflush(stderr);
  80 }
  81
  82 static void l_message(const char *pname, const char *msg)
  83 {
  84   if (pname) fprintf(stderr, "%s: ", pname);
  85   fprintf(stderr, "%s\n", msg);
  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(progname, 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 != 0) 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 int getargs(lua_State *L, char **argv, int n)
 158 {
 159   int narg;
 160   int i;
 161   int argc = 0;
 162   while (argv[argc]) argc++;  /* count total number of arguments */
 163   narg = argc - (n + 1);  /* number of arguments to the script */
 164   luaL_checkstack(L, narg + 3, "too many arguments to script");
 165   for (i = n+1; i < argc; i++)
 166     lua_pushstring(L, argv[i]);
 167   lua_createtable(L, narg, n + 1);
 168   for (i = 0; i < argc; i++) {
 169     lua_pushstring(L, argv[i]);
 170     lua_rawseti(L, -2, i - n);
 171   }
 172   return narg;
 173 }
 174
 175 static int dofile(lua_State *L, const char *name)
 176 {
 177   int status = luaL_loadfile(L, name) || docall(L, 0, 1);
 178   return report(L, status);
 179 }
 180
 181 static int dostring(lua_State *L, const char *s, const char *name)
 182 {
 183   int status = luaL_loadbuffer(L, s, strlen(s), name) || docall(L, 0, 1);
 184   return report(L, status);
 185 }
 186
 187 static int dolibrary(lua_State *L, const char *name)
 188 {
 189   lua_getglobal(L, "require");
 190   lua_pushstring(L, name);
 191   return report(L, docall(L, 1, 1));
 192 }
 193
 194 static void write_prompt(lua_State *L, int firstline)
 195 {
 196   const char *p;
 197   lua_getfield(L, LUA_GLOBALSINDEX, firstline ? "_PROMPT" : "_PROMPT2");
 198   p = lua_tostring(L, -1);
 199   if (p == NULL) p = firstline ? LUA_PROMPT : LUA_PROMPT2;
 200   fputs(p, stdout);
 201   fflush(stdout);
 202   lua_pop(L, 1);  /* remove global */
 203 }
 204
 205 static int incomplete(lua_State *L, int status)
 206 {
 207   if (status == LUA_ERRSYNTAX) {
 208     size_t lmsg;
 209     const char *msg = lua_tolstring(L, -1, &lmsg);
 210     const char *tp = msg + lmsg - (sizeof(LUA_QL("<eof>")) - 1);
 211     if (strstr(msg, LUA_QL("<eof>")) == tp) {
 212       lua_pop(L, 1);
 213       return 1;
 214     }
 215   }
 216   return 0;  /* else... */
 217 }
 218
 219 static int pushline(lua_State *L, int firstline)
 220 {
 221   char buf[LUA_MAXINPUT];
 222   write_prompt(L, firstline);
 223   if (fgets(buf, LUA_MAXINPUT, stdin)) {
 224     size_t len = strlen(buf);
 225     if (len > 0 && buf[len-1] == '\n')
 226       buf[len-1] = '\0';
 227     if (firstline && buf[0] == '=')
 228       lua_pushfstring(L, "return %s", buf+1);
 229     else
 230       lua_pushstring(L, buf);
 231     return 1;
 232   }
 233   return 0;
 234 }
 235
 236 static int loadline(lua_State *L)
 237 {
 238   int status;
 239   lua_settop(L, 0);
 240   if (!pushline(L, 1))
 241     return -1;  /* no input */
 242   for (;;) {  /* repeat until gets a complete line */
 243     status = luaL_loadbuffer(L, lua_tostring(L, 1), lua_strlen(L, 1), "=stdin");
 244     if (!incomplete(L, status)) break;  /* cannot try to add lines? */
 245     if (!pushline(L, 0))  /* no more input? */
 246       return -1;
 247     lua_pushliteral(L, "\n");  /* add a new line... */
 248     lua_insert(L, -2);  /* ...between the two lines */
 249     lua_concat(L, 3);  /* join them */
 250   }
 251   lua_remove(L, 1);  /* remove line */
 252   return status;
 253 }
 254
 255 static void dotty(lua_State *L)
 256 {
 257   int status;
 258   const char *oldprogname = progname;
 259   progname = NULL;
 260   while ((status = loadline(L)) != -1) {
 261     if (status == 0) status = docall(L, 0, 0);
 262     report(L, status);
 263     if (status == 0 && lua_gettop(L) > 0) {  /* any result to print? */
 264       lua_getglobal(L, "print");
 265       lua_insert(L, 1);
 266       if (lua_pcall(L, lua_gettop(L)-1, 0, 0) != 0)
 267         l_message(progname,
 268           lua_pushfstring(L, "error calling " LUA_QL("print") " (%s)",
 269                               lua_tostring(L, -1)));
 270     }
 271   }
 272   lua_settop(L, 0);  /* clear stack */
 273   fputs("\n", stdout);
 274   fflush(stdout);
 275   progname = oldprogname;
 276 }
 277
 278 static int handle_script(lua_State *L, char **argv, int n)
 279 {
 280   int status;
 281   const char *fname;
 282   int narg = getargs(L, argv, n);  /* collect arguments */
 283   lua_setglobal(L, "arg");
 284   fname = argv[n];
 285   if (strcmp(fname, "-") == 0 && strcmp(argv[n-1], "--") != 0)
 286     fname = NULL;  /* stdin */
 287   status = luaL_loadfile(L, fname);
 288   lua_insert(L, -(narg+1));
 289   if (status == 0)
 290     status = docall(L, narg, 0);
 291   else
 292     lua_pop(L, narg);
 293   return report(L, status);
 294 }
 295
 296 /* Load add-on module. */
 297 static int loadjitmodule(lua_State *L)
 298 {
 299   lua_getglobal(L, "require");
 300   lua_pushliteral(L, "jit.");
 301   lua_pushvalue(L, -3);
 302   lua_concat(L, 2);
 303   if (lua_pcall(L, 1, 1, 0)) {
 304     const char *msg = lua_tostring(L, -1);
 305     if (msg && !strncmp(msg, "module ", 7))
 306       goto nomodule;
 307     return report(L, 1);
 308   }
 309   lua_getfield(L, -1, "start");
 310   if (lua_isnil(L, -1)) {
 311   nomodule:
 312     l_message(progname,
 313               "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   return report(L, lua_pcall(L, narg, 0, 0));
 390 }
 391
 392 /* check that argument has no extra characters at the end */
 393 #define notail(x)       {if ((x)[2] != '\0') return -1;}
 394
 395 #define FLAGS_INTERACTIVE       1
 396 #define FLAGS_VERSION           2
 397 #define FLAGS_EXEC              4
 398 #define FLAGS_OPTION            8
 399 #define FLAGS_NOENV             16
 400
 401 static int collectargs(char **argv, int *flags)
 402 {
 403   int i;
 404   for (i = 1; argv[i] != NULL; i++) {
 405     if (argv[i][0] != '-')  /* Not an option? */
 406       return i;
 407     switch (argv[i][1]) {  /* Check option. */
 408     case '-':
 409       notail(argv[i]);
 410       return (argv[i+1] != NULL ? i+1 : 0);
 411     case '\0':
 412       return i;
 413     case 'i':
 414       notail(argv[i]);
 415       *flags |= FLAGS_INTERACTIVE;
 416       /* fallthrough */
 417     case 'v':
 418       notail(argv[i]);
 419       *flags |= FLAGS_VERSION;
 420       break;
 421     case 'e':
 422       *flags |= FLAGS_EXEC;
 423       /* fallthrough */
 424     case 'j':  /* LuaJIT extension */
 425     case 'l':
 426       *flags |= FLAGS_OPTION;
 427       if (argv[i][2] == '\0') {
 428         i++;
 429         if (argv[i] == NULL) return -1;
 430       }
 431       break;
 432     case 'O': break;  /* LuaJIT extension */
 433     case 'b':  /* LuaJIT extension */
 434       if (*flags) return -1;
 435       *flags |= FLAGS_EXEC;
 436       return 0;
 437     case 'E':
 438       *flags |= FLAGS_NOENV;
 439       break;
 440     default: return -1;  /* invalid option */
 441     }
 442   }
 443   return 0;
 444 }
 445
 446 static int runargs(lua_State *L, char **argv, int n)
 447 {
 448   int i;
 449   for (i = 1; i < n; i++) {
 450     if (argv[i] == NULL) continue;
 451     lua_assert(argv[i][0] == '-');
 452     switch (argv[i][1]) {  /* option */
 453     case 'e': {
 454       const char *chunk = argv[i] + 2;
 455       if (*chunk == '\0') chunk = argv[++i];
 456       lua_assert(chunk != NULL);
 457       if (dostring(L, chunk, "=(command line)") != 0)
 458         return 1;
 459       break;
 460       }
 461     case 'l': {
 462       const char *filename = argv[i] + 2;
 463       if (*filename == '\0') filename = argv[++i];
 464       lua_assert(filename != NULL);
 465       if (dolibrary(L, filename))
 466         return 1;  /* stop if file fails */
 467       break;
 468       }
 469     case 'j': {  /* LuaJIT extension */
 470       const char *cmd = argv[i] + 2;
 471       if (*cmd == '\0') cmd = argv[++i];
 472       lua_assert(cmd != NULL);
 473       if (dojitcmd(L, cmd))
 474         return 1;
 475       break;
 476       }
 477     case 'O':  /* LuaJIT extension */
 478       if (dojitopt(L, argv[i] + 2))
 479         return 1;
 480       break;
 481     case 'b':  /* LuaJIT extension */
 482       return dobytecode(L, argv+i);
 483     default: break;
 484     }
 485   }
 486   return 0;
 487 }
 488
 489 static int handle_luainit(lua_State *L)
 490 {
 491 #if LJ_TARGET_CONSOLE
 492   const char *init = NULL;
 493 #else
 494   const char *init = getenv(LUA_INIT);
 495 #endif
 496   if (init == NULL)
 497     return 0;  /* status OK */
 498   else if (init[0] == '@')
 499     return dofile(L, init+1);
 500   else
 501     return dostring(L, init, "=" LUA_INIT);
 502 }
 503
 504 static struct Smain {
 505   char **argv;
 506   int argc;
 507   int status;
 508 } smain;
 509
 510 static int pmain(lua_State *L)
 511 {
 512   struct Smain *s = &smain;
 513   char **argv = s->argv;
 514   int script;
 515   int flags = 0;
 516   globalL = L;
 517   if (argv[0] && argv[0][0]) progname = argv[0];
 518   LUAJIT_VERSION_SYM();  /* linker-enforced version check */
 519   script = collectargs(argv, &flags);
 520   if (script < 0) {  /* invalid args? */
 521     print_usage();
 522     s->status = 1;
 523     return 0;
 524   }
 525   if ((flags & FLAGS_NOENV)) {
 526     lua_pushboolean(L, 1);
 527     lua_setfield(L, LUA_REGISTRYINDEX, "LUA_NOENV");
 528   }
 529   lua_gc(L, LUA_GCSTOP, 0);  /* stop collector during initialization */
 530   luaL_openlibs(L);  /* open libraries */
 531   lua_gc(L, LUA_GCRESTART, -1);
 532   if (!(flags & FLAGS_NOENV)) {
 533     s->status = handle_luainit(L);
 534     if (s->status != 0) return 0;
 535   }
 536   if ((flags & FLAGS_VERSION)) print_version();
 537   s->status = runargs(L, argv, (script > 0) ? script : s->argc);
 538   if (s->status != 0) return 0;
 539   if (script) {
 540     s->status = handle_script(L, argv, script);
 541     if (s->status != 0) return 0;
 542   }
 543   if ((flags & FLAGS_INTERACTIVE)) {
 544     print_jit_status(L);
 545     dotty(L);
 546   } else if (script == 0 && !(flags & (FLAGS_EXEC|FLAGS_VERSION))) {
 547     if (lua_stdin_is_tty()) {
 548       print_version();
 549       print_jit_status(L);
 550       dotty(L);
 551     } else {
 552       dofile(L, NULL);  /* executes stdin as a file */
 553     }
 554   }
 555   return 0;
 556 }
 557
 558 int main(int argc, char **argv)
 559 {
 560   int status;
 561   lua_State *L = lua_open();  /* create state */
 562   if (L == NULL) {
 563     l_message(argv[0], "cannot create state: not enough memory");
 564     return EXIT_FAILURE;
 565   }
 566   smain.argc = argc;
 567   smain.argv = argv;
 568   status = lua_cpcall(L, pmain, NULL);
 569   report(L, status);
 570   lua_close(L);
 571   return (status || smain.status) ? EXIT_FAILURE : EXIT_SUCCESS;
 572 }
 573