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Member "memcached-1.6.15/vendor/lua/src/lua.c" (1 Oct 2021, 19320 Bytes) of package /linux/www/memcached-1.6.15.tar.gz:


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    1 /*
    2 ** $Id: lua.c $
    3 ** Lua stand-alone interpreter
    4 ** See Copyright Notice in lua.h
    5 */
    6 
    7 #define lua_c
    8 
    9 #include "lprefix.h"
   10 
   11 
   12 #include <stdio.h>
   13 #include <stdlib.h>
   14 #include <string.h>
   15 
   16 #include <signal.h>
   17 
   18 #include "lua.h"
   19 
   20 #include "lauxlib.h"
   21 #include "lualib.h"
   22 
   23 
   24 #if !defined(LUA_PROGNAME)
   25 #define LUA_PROGNAME        "lua"
   26 #endif
   27 
   28 #if !defined(LUA_INIT_VAR)
   29 #define LUA_INIT_VAR        "LUA_INIT"
   30 #endif
   31 
   32 #define LUA_INITVARVERSION  LUA_INIT_VAR LUA_VERSUFFIX
   33 
   34 
   35 static lua_State *globalL = NULL;
   36 
   37 static const char *progname = LUA_PROGNAME;
   38 
   39 
   40 #if defined(LUA_USE_POSIX)   /* { */
   41 
   42 /*
   43 ** Use 'sigaction' when available.
   44 */
   45 static void setsignal (int sig, void (*handler)(int)) {
   46   struct sigaction sa;
   47   sa.sa_handler = handler;
   48   sa.sa_flags = 0;
   49   sigemptyset(&sa.sa_mask);  /* do not mask any signal */
   50   sigaction(sig, &sa, NULL);
   51 }
   52 
   53 #else           /* }{ */
   54 
   55 #define setsignal            signal
   56 
   57 #endif                               /* } */
   58 
   59 
   60 /*
   61 ** Hook set by signal function to stop the interpreter.
   62 */
   63 static void lstop (lua_State *L, lua_Debug *ar) {
   64   (void)ar;  /* unused arg. */
   65   lua_sethook(L, NULL, 0, 0);  /* reset hook */
   66   luaL_error(L, "interrupted!");
   67 }
   68 
   69 
   70 /*
   71 ** Function to be called at a C signal. Because a C signal cannot
   72 ** just change a Lua state (as there is no proper synchronization),
   73 ** this function only sets a hook that, when called, will stop the
   74 ** interpreter.
   75 */
   76 static void laction (int i) {
   77   int flag = LUA_MASKCALL | LUA_MASKRET | LUA_MASKLINE | LUA_MASKCOUNT;
   78   setsignal(i, SIG_DFL); /* if another SIGINT happens, terminate process */
   79   lua_sethook(globalL, lstop, flag, 1);
   80 }
   81 
   82 
   83 static void print_usage (const char *badoption) {
   84   lua_writestringerror("%s: ", progname);
   85   if (badoption[1] == 'e' || badoption[1] == 'l')
   86     lua_writestringerror("'%s' needs argument\n", badoption);
   87   else
   88     lua_writestringerror("unrecognized option '%s'\n", badoption);
   89   lua_writestringerror(
   90   "usage: %s [options] [script [args]]\n"
   91   "Available options are:\n"
   92   "  -e stat  execute string 'stat'\n"
   93   "  -i       enter interactive mode after executing 'script'\n"
   94   "  -l name  require library 'name' into global 'name'\n"
   95   "  -v       show version information\n"
   96   "  -E       ignore environment variables\n"
   97   "  -W       turn warnings on\n"
   98   "  --       stop handling options\n"
   99   "  -        stop handling options and execute stdin\n"
  100   ,
  101   progname);
  102 }
  103 
  104 
  105 /*
  106 ** Prints an error message, adding the program name in front of it
  107 ** (if present)
  108 */
  109 static void l_message (const char *pname, const char *msg) {
  110   if (pname) lua_writestringerror("%s: ", pname);
  111   lua_writestringerror("%s\n", msg);
  112 }
  113 
  114 
  115 /*
  116 ** Check whether 'status' is not OK and, if so, prints the error
  117 ** message on the top of the stack. It assumes that the error object
  118 ** is a string, as it was either generated by Lua or by 'msghandler'.
  119 */
  120 static int report (lua_State *L, int status) {
  121   if (status != LUA_OK) {
  122     const char *msg = lua_tostring(L, -1);
  123     l_message(progname, msg);
  124     lua_pop(L, 1);  /* remove message */
  125   }
  126   return status;
  127 }
  128 
  129 
  130 /*
  131 ** Message handler used to run all chunks
  132 */
  133 static int msghandler (lua_State *L) {
  134   const char *msg = lua_tostring(L, 1);
  135   if (msg == NULL) {  /* is error object not a string? */
  136     if (luaL_callmeta(L, 1, "__tostring") &&  /* does it have a metamethod */
  137         lua_type(L, -1) == LUA_TSTRING)  /* that produces a string? */
  138       return 1;  /* that is the message */
  139     else
  140       msg = lua_pushfstring(L, "(error object is a %s value)",
  141                                luaL_typename(L, 1));
  142   }
  143   luaL_traceback(L, L, msg, 1);  /* append a standard traceback */
  144   return 1;  /* return the traceback */
  145 }
  146 
  147 
  148 /*
  149 ** Interface to 'lua_pcall', which sets appropriate message function
  150 ** and C-signal handler. Used to run all chunks.
  151 */
  152 static int docall (lua_State *L, int narg, int nres) {
  153   int status;
  154   int base = lua_gettop(L) - narg;  /* function index */
  155   lua_pushcfunction(L, msghandler);  /* push message handler */
  156   lua_insert(L, base);  /* put it under function and args */
  157   globalL = L;  /* to be available to 'laction' */
  158   setsignal(SIGINT, laction);  /* set C-signal handler */
  159   status = lua_pcall(L, narg, nres, base);
  160   setsignal(SIGINT, SIG_DFL); /* reset C-signal handler */
  161   lua_remove(L, base);  /* remove message handler from the stack */
  162   return status;
  163 }
  164 
  165 
  166 static void print_version (void) {
  167   lua_writestring(LUA_COPYRIGHT, strlen(LUA_COPYRIGHT));
  168   lua_writeline();
  169 }
  170 
  171 
  172 /*
  173 ** Create the 'arg' table, which stores all arguments from the
  174 ** command line ('argv'). It should be aligned so that, at index 0,
  175 ** it has 'argv[script]', which is the script name. The arguments
  176 ** to the script (everything after 'script') go to positive indices;
  177 ** other arguments (before the script name) go to negative indices.
  178 ** If there is no script name, assume interpreter's name as base.
  179 */
  180 static void createargtable (lua_State *L, char **argv, int argc, int script) {
  181   int i, narg;
  182   if (script == argc) script = 0;  /* no script name? */
  183   narg = argc - (script + 1);  /* number of positive indices */
  184   lua_createtable(L, narg, script + 1);
  185   for (i = 0; i < argc; i++) {
  186     lua_pushstring(L, argv[i]);
  187     lua_rawseti(L, -2, i - script);
  188   }
  189   lua_setglobal(L, "arg");
  190 }
  191 
  192 
  193 static int dochunk (lua_State *L, int status) {
  194   if (status == LUA_OK) status = docall(L, 0, 0);
  195   return report(L, status);
  196 }
  197 
  198 
  199 static int dofile (lua_State *L, const char *name) {
  200   return dochunk(L, luaL_loadfile(L, name));
  201 }
  202 
  203 
  204 static int dostring (lua_State *L, const char *s, const char *name) {
  205   return dochunk(L, luaL_loadbuffer(L, s, strlen(s), name));
  206 }
  207 
  208 
  209 /*
  210 ** Calls 'require(name)' and stores the result in a global variable
  211 ** with the given name.
  212 */
  213 static int dolibrary (lua_State *L, const char *name) {
  214   int status;
  215   lua_getglobal(L, "require");
  216   lua_pushstring(L, name);
  217   status = docall(L, 1, 1);  /* call 'require(name)' */
  218   if (status == LUA_OK)
  219     lua_setglobal(L, name);  /* global[name] = require return */
  220   return report(L, status);
  221 }
  222 
  223 
  224 /*
  225 ** Push on the stack the contents of table 'arg' from 1 to #arg
  226 */
  227 static int pushargs (lua_State *L) {
  228   int i, n;
  229   if (lua_getglobal(L, "arg") != LUA_TTABLE)
  230     luaL_error(L, "'arg' is not a table");
  231   n = (int)luaL_len(L, -1);
  232   luaL_checkstack(L, n + 3, "too many arguments to script");
  233   for (i = 1; i <= n; i++)
  234     lua_rawgeti(L, -i, i);
  235   lua_remove(L, -i);  /* remove table from the stack */
  236   return n;
  237 }
  238 
  239 
  240 static int handle_script (lua_State *L, char **argv) {
  241   int status;
  242   const char *fname = argv[0];
  243   if (strcmp(fname, "-") == 0 && strcmp(argv[-1], "--") != 0)
  244     fname = NULL;  /* stdin */
  245   status = luaL_loadfile(L, fname);
  246   if (status == LUA_OK) {
  247     int n = pushargs(L);  /* push arguments to script */
  248     status = docall(L, n, LUA_MULTRET);
  249   }
  250   return report(L, status);
  251 }
  252 
  253 
  254 /* bits of various argument indicators in 'args' */
  255 #define has_error   1   /* bad option */
  256 #define has_i       2   /* -i */
  257 #define has_v       4   /* -v */
  258 #define has_e       8   /* -e */
  259 #define has_E       16  /* -E */
  260 
  261 
  262 /*
  263 ** Traverses all arguments from 'argv', returning a mask with those
  264 ** needed before running any Lua code (or an error code if it finds
  265 ** any invalid argument). 'first' returns the first not-handled argument
  266 ** (either the script name or a bad argument in case of error).
  267 */
  268 static int collectargs (char **argv, int *first) {
  269   int args = 0;
  270   int i;
  271   for (i = 1; argv[i] != NULL; i++) {
  272     *first = i;
  273     if (argv[i][0] != '-')  /* not an option? */
  274         return args;  /* stop handling options */
  275     switch (argv[i][1]) {  /* else check option */
  276       case '-':  /* '--' */
  277         if (argv[i][2] != '\0')  /* extra characters after '--'? */
  278           return has_error;  /* invalid option */
  279         *first = i + 1;
  280         return args;
  281       case '\0':  /* '-' */
  282         return args;  /* script "name" is '-' */
  283       case 'E':
  284         if (argv[i][2] != '\0')  /* extra characters? */
  285           return has_error;  /* invalid option */
  286         args |= has_E;
  287         break;
  288       case 'W':
  289         if (argv[i][2] != '\0')  /* extra characters? */
  290           return has_error;  /* invalid option */
  291         break;
  292       case 'i':
  293         args |= has_i;  /* (-i implies -v) *//* FALLTHROUGH */
  294       case 'v':
  295         if (argv[i][2] != '\0')  /* extra characters? */
  296           return has_error;  /* invalid option */
  297         args |= has_v;
  298         break;
  299       case 'e':
  300         args |= has_e;  /* FALLTHROUGH */
  301       case 'l':  /* both options need an argument */
  302         if (argv[i][2] == '\0') {  /* no concatenated argument? */
  303           i++;  /* try next 'argv' */
  304           if (argv[i] == NULL || argv[i][0] == '-')
  305             return has_error;  /* no next argument or it is another option */
  306         }
  307         break;
  308       default:  /* invalid option */
  309         return has_error;
  310     }
  311   }
  312   *first = i;  /* no script name */
  313   return args;
  314 }
  315 
  316 
  317 /*
  318 ** Processes options 'e' and 'l', which involve running Lua code, and
  319 ** 'W', which also affects the state.
  320 ** Returns 0 if some code raises an error.
  321 */
  322 static int runargs (lua_State *L, char **argv, int n) {
  323   int i;
  324   for (i = 1; i < n; i++) {
  325     int option = argv[i][1];
  326     lua_assert(argv[i][0] == '-');  /* already checked */
  327     switch (option) {
  328       case 'e':  case 'l': {
  329         int status;
  330         const char *extra = argv[i] + 2;  /* both options need an argument */
  331         if (*extra == '\0') extra = argv[++i];
  332         lua_assert(extra != NULL);
  333         status = (option == 'e')
  334                  ? dostring(L, extra, "=(command line)")
  335                  : dolibrary(L, extra);
  336         if (status != LUA_OK) return 0;
  337         break;
  338       }
  339       case 'W':
  340         lua_warning(L, "@on", 0);  /* warnings on */
  341         break;
  342     }
  343   }
  344   return 1;
  345 }
  346 
  347 
  348 static int handle_luainit (lua_State *L) {
  349   const char *name = "=" LUA_INITVARVERSION;
  350   const char *init = getenv(name + 1);
  351   if (init == NULL) {
  352     name = "=" LUA_INIT_VAR;
  353     init = getenv(name + 1);  /* try alternative name */
  354   }
  355   if (init == NULL) return LUA_OK;
  356   else if (init[0] == '@')
  357     return dofile(L, init+1);
  358   else
  359     return dostring(L, init, name);
  360 }
  361 
  362 
  363 /*
  364 ** {==================================================================
  365 ** Read-Eval-Print Loop (REPL)
  366 ** ===================================================================
  367 */
  368 
  369 #if !defined(LUA_PROMPT)
  370 #define LUA_PROMPT      "> "
  371 #define LUA_PROMPT2     ">> "
  372 #endif
  373 
  374 #if !defined(LUA_MAXINPUT)
  375 #define LUA_MAXINPUT        512
  376 #endif
  377 
  378 
  379 /*
  380 ** lua_stdin_is_tty detects whether the standard input is a 'tty' (that
  381 ** is, whether we're running lua interactively).
  382 */
  383 #if !defined(lua_stdin_is_tty)  /* { */
  384 
  385 #if defined(LUA_USE_POSIX)  /* { */
  386 
  387 #include <unistd.h>
  388 #define lua_stdin_is_tty()  isatty(0)
  389 
  390 #elif defined(LUA_USE_WINDOWS)  /* }{ */
  391 
  392 #include <io.h>
  393 #include <windows.h>
  394 
  395 #define lua_stdin_is_tty()  _isatty(_fileno(stdin))
  396 
  397 #else               /* }{ */
  398 
  399 /* ISO C definition */
  400 #define lua_stdin_is_tty()  1  /* assume stdin is a tty */
  401 
  402 #endif              /* } */
  403 
  404 #endif              /* } */
  405 
  406 
  407 /*
  408 ** lua_readline defines how to show a prompt and then read a line from
  409 ** the standard input.
  410 ** lua_saveline defines how to "save" a read line in a "history".
  411 ** lua_freeline defines how to free a line read by lua_readline.
  412 */
  413 #if !defined(lua_readline)  /* { */
  414 
  415 #if defined(LUA_USE_READLINE)   /* { */
  416 
  417 #include <readline/readline.h>
  418 #include <readline/history.h>
  419 #define lua_initreadline(L) ((void)L, rl_readline_name="lua")
  420 #define lua_readline(L,b,p) ((void)L, ((b)=readline(p)) != NULL)
  421 #define lua_saveline(L,line)    ((void)L, add_history(line))
  422 #define lua_freeline(L,b)   ((void)L, free(b))
  423 
  424 #else               /* }{ */
  425 
  426 #define lua_initreadline(L)  ((void)L)
  427 #define lua_readline(L,b,p) \
  428         ((void)L, fputs(p, stdout), fflush(stdout),  /* show prompt */ \
  429         fgets(b, LUA_MAXINPUT, stdin) != NULL)  /* get line */
  430 #define lua_saveline(L,line)    { (void)L; (void)line; }
  431 #define lua_freeline(L,b)   { (void)L; (void)b; }
  432 
  433 #endif              /* } */
  434 
  435 #endif              /* } */
  436 
  437 
  438 /*
  439 ** Return the string to be used as a prompt by the interpreter. Leave
  440 ** the string (or nil, if using the default value) on the stack, to keep
  441 ** it anchored.
  442 */
  443 static const char *get_prompt (lua_State *L, int firstline) {
  444   if (lua_getglobal(L, firstline ? "_PROMPT" : "_PROMPT2") == LUA_TNIL)
  445     return (firstline ? LUA_PROMPT : LUA_PROMPT2);  /* use the default */
  446   else {  /* apply 'tostring' over the value */
  447     const char *p = luaL_tolstring(L, -1, NULL);
  448     lua_remove(L, -2);  /* remove original value */
  449     return p;
  450   }
  451 }
  452 
  453 /* mark in error messages for incomplete statements */
  454 #define EOFMARK     "<eof>"
  455 #define marklen     (sizeof(EOFMARK)/sizeof(char) - 1)
  456 
  457 
  458 /*
  459 ** Check whether 'status' signals a syntax error and the error
  460 ** message at the top of the stack ends with the above mark for
  461 ** incomplete statements.
  462 */
  463 static int incomplete (lua_State *L, int status) {
  464   if (status == LUA_ERRSYNTAX) {
  465     size_t lmsg;
  466     const char *msg = lua_tolstring(L, -1, &lmsg);
  467     if (lmsg >= marklen && strcmp(msg + lmsg - marklen, EOFMARK) == 0) {
  468       lua_pop(L, 1);
  469       return 1;
  470     }
  471   }
  472   return 0;  /* else... */
  473 }
  474 
  475 
  476 /*
  477 ** Prompt the user, read a line, and push it into the Lua stack.
  478 */
  479 static int pushline (lua_State *L, int firstline) {
  480   char buffer[LUA_MAXINPUT];
  481   char *b = buffer;
  482   size_t l;
  483   const char *prmt = get_prompt(L, firstline);
  484   int readstatus = lua_readline(L, b, prmt);
  485   if (readstatus == 0)
  486     return 0;  /* no input (prompt will be popped by caller) */
  487   lua_pop(L, 1);  /* remove prompt */
  488   l = strlen(b);
  489   if (l > 0 && b[l-1] == '\n')  /* line ends with newline? */
  490     b[--l] = '\0';  /* remove it */
  491   if (firstline && b[0] == '=')  /* for compatibility with 5.2, ... */
  492     lua_pushfstring(L, "return %s", b + 1);  /* change '=' to 'return' */
  493   else
  494     lua_pushlstring(L, b, l);
  495   lua_freeline(L, b);
  496   return 1;
  497 }
  498 
  499 
  500 /*
  501 ** Try to compile line on the stack as 'return <line>;'; on return, stack
  502 ** has either compiled chunk or original line (if compilation failed).
  503 */
  504 static int addreturn (lua_State *L) {
  505   const char *line = lua_tostring(L, -1);  /* original line */
  506   const char *retline = lua_pushfstring(L, "return %s;", line);
  507   int status = luaL_loadbuffer(L, retline, strlen(retline), "=stdin");
  508   if (status == LUA_OK) {
  509     lua_remove(L, -2);  /* remove modified line */
  510     if (line[0] != '\0')  /* non empty? */
  511       lua_saveline(L, line);  /* keep history */
  512   }
  513   else
  514     lua_pop(L, 2);  /* pop result from 'luaL_loadbuffer' and modified line */
  515   return status;
  516 }
  517 
  518 
  519 /*
  520 ** Read multiple lines until a complete Lua statement
  521 */
  522 static int multiline (lua_State *L) {
  523   for (;;) {  /* repeat until gets a complete statement */
  524     size_t len;
  525     const char *line = lua_tolstring(L, 1, &len);  /* get what it has */
  526     int status = luaL_loadbuffer(L, line, len, "=stdin");  /* try it */
  527     if (!incomplete(L, status) || !pushline(L, 0)) {
  528       lua_saveline(L, line);  /* keep history */
  529       return status;  /* cannot or should not try to add continuation line */
  530     }
  531     lua_pushliteral(L, "\n");  /* add newline... */
  532     lua_insert(L, -2);  /* ...between the two lines */
  533     lua_concat(L, 3);  /* join them */
  534   }
  535 }
  536 
  537 
  538 /*
  539 ** Read a line and try to load (compile) it first as an expression (by
  540 ** adding "return " in front of it) and second as a statement. Return
  541 ** the final status of load/call with the resulting function (if any)
  542 ** in the top of the stack.
  543 */
  544 static int loadline (lua_State *L) {
  545   int status;
  546   lua_settop(L, 0);
  547   if (!pushline(L, 1))
  548     return -1;  /* no input */
  549   if ((status = addreturn(L)) != LUA_OK)  /* 'return ...' did not work? */
  550     status = multiline(L);  /* try as command, maybe with continuation lines */
  551   lua_remove(L, 1);  /* remove line from the stack */
  552   lua_assert(lua_gettop(L) == 1);
  553   return status;
  554 }
  555 
  556 
  557 /*
  558 ** Prints (calling the Lua 'print' function) any values on the stack
  559 */
  560 static void l_print (lua_State *L) {
  561   int n = lua_gettop(L);
  562   if (n > 0) {  /* any result to be printed? */
  563     luaL_checkstack(L, LUA_MINSTACK, "too many results to print");
  564     lua_getglobal(L, "print");
  565     lua_insert(L, 1);
  566     if (lua_pcall(L, n, 0, 0) != LUA_OK)
  567       l_message(progname, lua_pushfstring(L, "error calling 'print' (%s)",
  568                                              lua_tostring(L, -1)));
  569   }
  570 }
  571 
  572 
  573 /*
  574 ** Do the REPL: repeatedly read (load) a line, evaluate (call) it, and
  575 ** print any results.
  576 */
  577 static void doREPL (lua_State *L) {
  578   int status;
  579   const char *oldprogname = progname;
  580   progname = NULL;  /* no 'progname' on errors in interactive mode */
  581   lua_initreadline(L);
  582   while ((status = loadline(L)) != -1) {
  583     if (status == LUA_OK)
  584       status = docall(L, 0, LUA_MULTRET);
  585     if (status == LUA_OK) l_print(L);
  586     else report(L, status);
  587   }
  588   lua_settop(L, 0);  /* clear stack */
  589   lua_writeline();
  590   progname = oldprogname;
  591 }
  592 
  593 /* }================================================================== */
  594 
  595 
  596 /*
  597 ** Main body of stand-alone interpreter (to be called in protected mode).
  598 ** Reads the options and handles them all.
  599 */
  600 static int pmain (lua_State *L) {
  601   int argc = (int)lua_tointeger(L, 1);
  602   char **argv = (char **)lua_touserdata(L, 2);
  603   int script;
  604   int args = collectargs(argv, &script);
  605   luaL_checkversion(L);  /* check that interpreter has correct version */
  606   if (argv[0] && argv[0][0]) progname = argv[0];
  607   if (args == has_error) {  /* bad arg? */
  608     print_usage(argv[script]);  /* 'script' has index of bad arg. */
  609     return 0;
  610   }
  611   if (args & has_v)  /* option '-v'? */
  612     print_version();
  613   if (args & has_E) {  /* option '-E'? */
  614     lua_pushboolean(L, 1);  /* signal for libraries to ignore env. vars. */
  615     lua_setfield(L, LUA_REGISTRYINDEX, "LUA_NOENV");
  616   }
  617   luaL_openlibs(L);  /* open standard libraries */
  618   createargtable(L, argv, argc, script);  /* create table 'arg' */
  619   lua_gc(L, LUA_GCGEN, 0, 0);  /* GC in generational mode */
  620   if (!(args & has_E)) {  /* no option '-E'? */
  621     if (handle_luainit(L) != LUA_OK)  /* run LUA_INIT */
  622       return 0;  /* error running LUA_INIT */
  623   }
  624   if (!runargs(L, argv, script))  /* execute arguments -e and -l */
  625     return 0;  /* something failed */
  626   if (script < argc &&  /* execute main script (if there is one) */
  627       handle_script(L, argv + script) != LUA_OK)
  628     return 0;
  629   if (args & has_i)  /* -i option? */
  630     doREPL(L);  /* do read-eval-print loop */
  631   else if (script == argc && !(args & (has_e | has_v))) {  /* no arguments? */
  632     if (lua_stdin_is_tty()) {  /* running in interactive mode? */
  633       print_version();
  634       doREPL(L);  /* do read-eval-print loop */
  635     }
  636     else dofile(L, NULL);  /* executes stdin as a file */
  637   }
  638   lua_pushboolean(L, 1);  /* signal no errors */
  639   return 1;
  640 }
  641 
  642 
  643 int main (int argc, char **argv) {
  644   int status, result;
  645   lua_State *L = luaL_newstate();  /* create state */
  646   if (L == NULL) {
  647     l_message(argv[0], "cannot create state: not enough memory");
  648     return EXIT_FAILURE;
  649   }
  650   lua_pushcfunction(L, &pmain);  /* to call 'pmain' in protected mode */
  651   lua_pushinteger(L, argc);  /* 1st argument */
  652   lua_pushlightuserdata(L, argv); /* 2nd argument */
  653   status = lua_pcall(L, 2, 1, 0);  /* do the call */
  654   result = lua_toboolean(L, -1);  /* get result */
  655   report(L, status);
  656   lua_close(L);
  657   return (result && status == LUA_OK) ? EXIT_SUCCESS : EXIT_FAILURE;
  658 }
  659