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