#define lua_c

#include "lprefix.h"

#include <signal.h>

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#include "lua.h"

#include "lauxlib.h"

#include "lualib.h"

#if !defined(LUA_PROMPT)

#define LUA_PROMPT "> "

#define LUA_PROMPT2 ">> "

#if !defined(LUA_PROGNAME)

#define LUA_PROGNAME "lua"

#if !defined(LUA_MAXINPUT)

#define LUA_MAXINPUT 512

#if !defined(LUA_INIT_VAR)

#define LUA_INIT_VAR "LUA_INIT"

#define LUA_INITVARVERSION \

LUA_INIT_VAR "_" LUA_VERSION_MAJOR "_" LUA_VERSION_MINOR

#if !defined(lua_stdin_is_tty) /* { */

#if defined(LUA_USE_POSIX) /* { */

#include <unistd.h>

#define lua_stdin_is_tty() isatty(0)

#elif defined(LUA_USE_WINDOWS) /* }{ */

#include <io.h>

#define lua_stdin_is_tty() _isatty(_fileno(stdin))

#else /* }{ */

#define lua_stdin_is_tty() 1 /* assume stdin is a tty */

#endif /* } */

#endif /* } */

#if !defined(lua_readline) /* { */

#if defined(LUA_USE_READLINE) /* { */

#include <readline/readline.h>

#include <readline/history.h>

#define lua_readline(L,b,p) ((void)L, ((b)=readline(p)) != NULL)

#define lua_saveline(L,line) ((void)L, add_history(line))

#define lua_freeline(L,b) ((void)L, free(b))

#else /* }{ */

#define lua_readline(L,b,p) \

((void)L, fputs(p, stdout), fflush(stdout), /* show prompt */ \

fgets(b, LUA_MAXINPUT, stdin) != NULL) /* get line */

#define lua_saveline(L,line) { (void)L; (void)line; }

#define lua_freeline(L,b) { (void)L; (void)b; }

#endif /* } */

#endif /* } */

static lua_State *globalL = NULL;

static const char *progname = LUA_PROGNAME;

static void lstop (lua_State *L, lua_Debug *ar) {

(void)ar; /* unused arg. */

lua_sethook(L, NULL, 0, 0); /* reset hook */

luaL_error(L, "interrupted!");

}

static void laction (int i) {

signal(i, SIG_DFL); /* if another SIGINT happens, terminate process */

lua_sethook(globalL, lstop, LUA_MASKCALL | LUA_MASKRET | LUA_MASKCOUNT, 1);

}

static void print_usage (const char *badoption) {

lua_writestringerror("%s: ", progname);

if (badoption[1] == 'e' || badoption[1] == 'l')

lua_writestringerror("'%s' needs argument\n", badoption);

else

lua_writestringerror("unrecognized option '%s'\n", badoption);

lua_writestringerror(

"usage: %s [options] [script [args]]\n"

"Available options are:\n"

" -e stat execute string 'stat'\n"

" -i enter interactive mode after executing 'script'\n"

" -l name require library 'name'\n"

" -v show version information\n"

" -E ignore environment variables\n"

" -- stop handling options\n"

" - stop handling options and execute stdin\n"

,

progname);

}

static void l_message (const char *pname, const char *msg) {

if (pname) lua_writestringerror("%s: ", pname);

lua_writestringerror("%s\n", msg);

}

static int report (lua_State *L, int status) {

if (status != LUA_OK) {

const char *msg = lua_tostring(L, -1);

l_message(progname, msg);

lua_pop(L, 1); /* remove message */

}

return status;

}

static int msghandler (lua_State *L) {

const char *msg = lua_tostring(L, 1);

if (msg == NULL) { /* is error object not a string? */

if (luaL_callmeta(L, 1, "__tostring") && /* does it have a metamethod */

lua_type(L, -1) == LUA_TSTRING) /* that produces a string? */

return 1; /* that is the message */

else

msg = lua_pushfstring(L, "(error object is a %s value)",

luaL_typename(L, 1));

}

luaL_traceback(L, L, msg, 1); /* append a standard traceback */

return 1; /* return the traceback */

}

static int docall (lua_State *L, int narg, int nres) {

int status;

int base = lua_gettop(L) - narg; /* function index */

lua_pushcfunction(L, msghandler); /* push message handler */

lua_insert(L, base); /* put it under function and args */

globalL = L; /* to be available to 'laction' */

signal(SIGINT, laction); /* set C-signal handler */

status = lua_pcall(L, narg, nres, base);

signal(SIGINT, SIG_DFL); /* reset C-signal handler */

lua_remove(L, base); /* remove message handler from the stack */

return status;

}

static void print_version (void) {

lua_writestring(LUA_COPYRIGHT, strlen(LUA_COPYRIGHT));

lua_writeline();

}

static void createargtable (lua_State *L, char **argv, int argc, int script) {

int i, narg;

if (script == argc) script = 0; /* no script name? */

narg = argc - (script + 1); /* number of positive indices */

lua_createtable(L, narg, script + 1);

for (i = 0; i < argc; i++) {

lua_pushstring(L, argv[i]);

lua_rawseti(L, -2, i - script);

}

lua_setglobal(L, "arg");

}

static int dochunk (lua_State *L, int status) {

if (status == LUA_OK) status = docall(L, 0, 0);

return report(L, status);

}

static int dofile (lua_State *L, const char *name) {

return dochunk(L, luaL_loadfile(L, name));

}

static int dostring (lua_State *L, const char *s, const char *name) {

return dochunk(L, luaL_loadbuffer(L, s, strlen(s), name));

}

static int dolibrary (lua_State *L, const char *name) {

int status;

lua_getglobal(L, "require");

lua_pushstring(L, name);

status = docall(L, 1, 1); /* call 'require(name)' */

if (status == LUA_OK)

lua_setglobal(L, name); /* global[name] = require return */

return report(L, status);

}

static const char *get_prompt (lua_State *L, int firstline) {

const char *p;

lua_getglobal(L, firstline ? "_PROMPT" : "_PROMPT2");

p = lua_tostring(L, -1);

if (p == NULL) p = (firstline ? LUA_PROMPT : LUA_PROMPT2);

return p;

}

#define EOFMARK "<eof>"

#define marklen (sizeof(EOFMARK)/sizeof(char) - 1)

static int incomplete (lua_State *L, int status) {

if (status == LUA_ERRSYNTAX) {

size_t lmsg;

const char *msg = lua_tolstring(L, -1, &lmsg);

if (lmsg >= marklen && strcmp(msg + lmsg - marklen, EOFMARK) == 0) {

lua_pop(L, 1);

return 1;

}

}

return 0; /* else... */

}

static int pushline (lua_State *L, int firstline) {

char buffer[LUA_MAXINPUT];

char *b = buffer;

size_t l;

const char *prmt = get_prompt(L, firstline);

int readstatus = lua_readline(L, b, prmt);

if (readstatus == 0)

return 0; /* no input (prompt will be popped by caller) */

lua_pop(L, 1); /* remove prompt */

l = strlen(b);

if (l > 0 && b[l-1] == '\n') /* line ends with newline? */

b[--l] = '\0'; /* remove it */

if (firstline && b[0] == '=') /* for compatibility with 5.2, ... */

lua_pushfstring(L, "return %s", b + 1); /* change '=' to 'return' */

else

lua_pushlstring(L, b, l);

lua_freeline(L, b);

return 1;

}

static int addreturn (lua_State *L) {

const char *line = lua_tostring(L, -1); /* original line */

const char *retline = lua_pushfstring(L, "return %s;", line);

int status = luaL_loadbuffer(L, retline, strlen(retline), "=stdin");

if (status == LUA_OK) {

lua_remove(L, -2); /* remove modified line */

if (line[0] != '\0') /* non empty? */

lua_saveline(L, line); /* keep history */

}

else

lua_pop(L, 2); /* pop result from 'luaL_loadbuffer' and modified line */

return status;

}

static int multiline (lua_State *L) {

for (;;) { /* repeat until gets a complete statement */

size_t len;

const char *line = lua_tolstring(L, 1, &len); /* get what it has */

int status = luaL_loadbuffer(L, line, len, "=stdin"); /* try it */

if (!incomplete(L, status) || !pushline(L, 0)) {

lua_saveline(L, line); /* keep history */

return status; /* cannot or should not try to add continuation line */

}

lua_pushliteral(L, "\n"); /* add newline... */

lua_insert(L, -2); /* ...between the two lines */

lua_concat(L, 3); /* join them */

}

}

static int loadline (lua_State *L) {

int status;

lua_settop(L, 0);

if (!pushline(L, 1))

return -1; /* no input */

if ((status = addreturn(L)) != LUA_OK) /* 'return ...' did not work? */

status = multiline(L); /* try as command, maybe with continuation lines */

lua_remove(L, 1); /* remove line from the stack */

lua_assert(lua_gettop(L) == 1);

return status;

}

static void l_print (lua_State *L) {

int n = lua_gettop(L);

if (n > 0) { /* any result to be printed? */

luaL_checkstack(L, LUA_MINSTACK, "too many results to print");

lua_getglobal(L, "print");

lua_insert(L, 1);

if (lua_pcall(L, n, 0, 0) != LUA_OK)

l_message(progname, lua_pushfstring(L, "error calling 'print' (%s)",

lua_tostring(L, -1)));

}

}

static void doREPL (lua_State *L) {

int status;

const char *oldprogname = progname;

progname = NULL; /* no 'progname' on errors in interactive mode */

while ((status = loadline(L)) != -1) {

if (status == LUA_OK)

status = docall(L, 0, LUA_MULTRET);

if (status == LUA_OK) l_print(L);

else report(L, status);

}

lua_settop(L, 0); /* clear stack */

lua_writeline();

progname = oldprogname;

}

static int pushargs (lua_State *L) {

int i, n;

if (lua_getglobal(L, "arg") != LUA_TTABLE)

luaL_error(L, "'arg' is not a table");

n = (int)luaL_len(L, -1);

luaL_checkstack(L, n + 3, "too many arguments to script");

for (i = 1; i <= n; i++)

lua_rawgeti(L, -i, i);

lua_remove(L, -i); /* remove table from the stack */

return n;

}

static int handle_script (lua_State *L, char **argv) {

int status;

const char *fname = argv[0];

if (strcmp(fname, "-") == 0 && strcmp(argv[-1], "--") != 0)

fname = NULL; /* stdin */

status = luaL_loadfile(L, fname);

if (status == LUA_OK) {

int n = pushargs(L); /* push arguments to script */

status = docall(L, n, LUA_MULTRET);

}

return report(L, status);

}

#define has_error 1 /* bad option */

#define has_i 2 /* -i */

#define has_v 4 /* -v */

#define has_e 8 /* -e */

#define has_E 16 /* -E */

static int collectargs (char **argv, int *first) {

int args = 0;

int i;

for (i = 1; argv[i] != NULL; i++) {

*first = i;

if (argv[i][0] != '-') /* not an option? */

return args; /* stop handling options */

switch (argv[i][1]) { /* else check option */

case '-': /* '--' */

if (argv[i][2] != '\0') /* extra characters after '--'? */

return has_error; /* invalid option */

*first = i + 1;

return args;

case '\0': /* '-' */

return args; /* script "name" is '-' */

case 'E':

if (argv[i][2] != '\0') /* extra characters after 1st? */

return has_error; /* invalid option */

args |= has_E;

break;

case 'i':

args |= has_i; /* (-i implies -v) *//* FALLTHROUGH */

case 'v':

if (argv[i][2] != '\0') /* extra characters after 1st? */

return has_error; /* invalid option */

args |= has_v;

break;

case 'e':

args |= has_e; /* FALLTHROUGH */

case 'l': /* both options need an argument */

if (argv[i][2] == '\0') { /* no concatenated argument? */

i++; /* try next 'argv' */

if (argv[i] == NULL || argv[i][0] == '-')

return has_error; /* no next argument or it is another option */

}

break;

default: /* invalid option */

return has_error;

}

}

*first = i; /* no script name */

return args;

}

static int runargs (lua_State *L, char **argv, int n) {

int i;

for (i = 1; i < n; i++) {

int option = argv[i][1];

lua_assert(argv[i][0] == '-'); /* already checked */

if (option == 'e' || option == 'l') {

int status;

const char *extra = argv[i] + 2; /* both options need an argument */

if (*extra == '\0') extra = argv[++i];

lua_assert(extra != NULL);

status = (option == 'e')

? dostring(L, extra, "=(command line)")

: dolibrary(L, extra);

if (status != LUA_OK) return 0;

}

}

return 1;

}

static int handle_luainit (lua_State *L) {

const char *name = "=" LUA_INITVARVERSION;

const char *init = getenv(name + 1);

if (init == NULL) {

name = "=" LUA_INIT_VAR;

init = getenv(name + 1); /* try alternative name */

}

if (init == NULL) return LUA_OK;

else if (init[0] == '@')

return dofile(L, init+1);

else

return dostring(L, init, name);

}

static int pmain (lua_State *L) {

int argc = (int)lua_tointeger(L, 1);

char **argv = (char **)lua_touserdata(L, 2);

int script;

int args = collectargs(argv, &script);

luaL_checkversion(L); /* check that interpreter has correct version */

if (argv[0] && argv[0][0]) progname = argv[0];

if (args == has_error) { /* bad arg? */

print_usage(argv[script]); /* 'script' has index of bad arg. */

return 0;

}

if (args & has_v) /* option '-v'? */

print_version();

if (args & has_E) { /* option '-E'? */

lua_pushboolean(L, 1); /* signal for libraries to ignore env. vars. */

lua_setfield(L, LUA_REGISTRYINDEX, "LUA_NOENV");

}

luaL_openlibs(L); /* open standard libraries */

createargtable(L, argv, argc, script); /* create table 'arg' */

if (!(args & has_E)) { /* no option '-E'? */

if (handle_luainit(L) != LUA_OK) /* run LUA_INIT */

return 0; /* error running LUA_INIT */

}

if (!runargs(L, argv, script)) /* execute arguments -e and -l */

return 0; /* something failed */

if (script < argc && /* execute main script (if there is one) */

handle_script(L, argv + script) != LUA_OK)

return 0;

if (args & has_i) /* -i option? */

doREPL(L); /* do read-eval-print loop */

else if (script == argc && !(args & (has_e | has_v))) { /* no arguments? */

if (lua_stdin_is_tty()) { /* running in interactive mode? */

print_version();

doREPL(L); /* do read-eval-print loop */

}

else dofile(L, NULL); /* executes stdin as a file */

}

lua_pushboolean(L, 1); /* signal no errors */

return 1;

}

int main (int argc, char **argv) {

int status, result;

lua_State *L = luaL_newstate(); /* create state */

if (L == NULL) {

l_message(argv[0], "cannot create state: not enough memory");

return EXIT_FAILURE;

}

lua_pushcfunction(L, &pmain); /* to call 'pmain' in protected mode */

lua_pushinteger(L, argc); /* 1st argument */

lua_pushlightuserdata(L, argv); /* 2nd argument */

status = lua_pcall(L, 2, 1, 0); /* do the call */

result = lua_toboolean(L, -1); /* get result */

report(L, status);

lua_close(L);

return (result && status == LUA_OK) ? EXIT_SUCCESS : EXIT_FAILURE;

}