/tags/rel-1.3.35/Examples/lua/lua.c
C | 439 lines | 339 code | 77 blank | 23 comment | 75 complexity | 19617bbbee4ded669d6f2e6ed8b50346 MD5 | raw file
Possible License(s): LGPL-2.1, Cube, GPL-3.0, 0BSD, GPL-2.0
1/*
2** $Id: lua.c 7470 2005-09-20 19:35:23Z wsfulton $
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/*
22** generic extra include file
23*/
24#ifdef LUA_USERCONFIG
25#include LUA_USERCONFIG
26#endif
27
28
29/*
30** definition of `isatty'
31*/
32#ifdef _POSIX_C_SOURCE
33#include <unistd.h>
34#define stdin_is_tty() isatty(0)
35#else
36#define stdin_is_tty() 1 /* assume stdin is a tty */
37#endif
38
39
40
41#ifndef PROMPT
42#define PROMPT "> "
43#endif
44
45
46#ifndef PROMPT2
47#define PROMPT2 ">> "
48#endif
49
50#ifndef PROGNAME
51#define PROGNAME "lua"
52#endif
53
54#ifndef lua_userinit
55#define lua_userinit(L) openstdlibs(L)
56#endif
57
58
59#ifndef LUA_EXTRALIBS
60#define LUA_EXTRALIBS /* empty */
61#endif
62
63
64static lua_State *L = NULL;
65
66static const char *progname = PROGNAME;
67
68extern int Example_Init(lua_State* L);
69
70static const luaL_reg lualibs[] = {
71 {"base", luaopen_base},
72 {"table", luaopen_table},
73 {"io", luaopen_io},
74 {"string", luaopen_string},
75 {"math", luaopen_math},
76 {"debug", luaopen_debug},
77 {"loadlib", luaopen_loadlib},
78 /* add your libraries here */
79 {"example", Example_Init},
80 LUA_EXTRALIBS
81 {NULL, NULL}
82};
83
84
85
86static void lstop (lua_State *l, lua_Debug *ar) {
87 (void)ar; /* unused arg. */
88 lua_sethook(l, NULL, 0, 0);
89 luaL_error(l, "interrupted!");
90}
91
92
93static void laction (int i) {
94 signal(i, SIG_DFL); /* if another SIGINT happens before lstop,
95 terminate process (default action) */
96 lua_sethook(L, lstop, LUA_MASKCALL | LUA_MASKRET | LUA_MASKCOUNT, 1);
97}
98
99
100static void print_usage (void) {
101 fprintf(stderr,
102 "usage: %s [options] [script [args]].\n"
103 "Available options are:\n"
104 " - execute stdin as a file\n"
105 " -e stat execute string `stat'\n"
106 " -i enter interactive mode after executing `script'\n"
107 " -l name load and run library `name'\n"
108 " -v show version information\n"
109 " -- stop handling options\n" ,
110 progname);
111}
112
113
114static void l_message (const char *pname, const char *msg) {
115 if (pname) fprintf(stderr, "%s: ", pname);
116 fprintf(stderr, "%s\n", msg);
117}
118
119
120static int report (int status) {
121 const char *msg;
122 if (status) {
123 msg = lua_tostring(L, -1);
124 if (msg == NULL) msg = "(error with no message)";
125 l_message(progname, msg);
126 lua_pop(L, 1);
127 }
128 return status;
129}
130
131
132static int lcall (int narg, int clear) {
133 int status;
134 int base = lua_gettop(L) - narg; /* function index */
135 lua_pushliteral(L, "_TRACEBACK");
136 lua_rawget(L, LUA_GLOBALSINDEX); /* get traceback function */
137 lua_insert(L, base); /* put it under chunk and args */
138 signal(SIGINT, laction);
139 status = lua_pcall(L, narg, (clear ? 0 : LUA_MULTRET), base);
140 signal(SIGINT, SIG_DFL);
141 lua_remove(L, base); /* remove traceback function */
142 return status;
143}
144
145
146static void print_version (void) {
147 l_message(NULL, LUA_VERSION " " LUA_COPYRIGHT);
148}
149
150
151static void getargs (char *argv[], int n) {
152 int i;
153 lua_newtable(L);
154 for (i=0; argv[i]; i++) {
155 lua_pushnumber(L, i - n);
156 lua_pushstring(L, argv[i]);
157 lua_rawset(L, -3);
158 }
159 /* arg.n = maximum index in table `arg' */
160 lua_pushliteral(L, "n");
161 lua_pushnumber(L, i-n-1);
162 lua_rawset(L, -3);
163}
164
165
166static int docall (int status) {
167 if (status == 0) status = lcall(0, 1);
168 return report(status);
169}
170
171
172static int file_input (const char *name) {
173 return docall(luaL_loadfile(L, name));
174}
175
176
177static int dostring (const char *s, const char *name) {
178 return docall(luaL_loadbuffer(L, s, strlen(s), name));
179}
180
181
182static int load_file (const char *name) {
183 lua_pushliteral(L, "require");
184 lua_rawget(L, LUA_GLOBALSINDEX);
185 if (!lua_isfunction(L, -1)) { /* no `require' defined? */
186 lua_pop(L, 1);
187 return file_input(name);
188 }
189 else {
190 lua_pushstring(L, name);
191 return report(lcall(1, 1));
192 }
193}
194
195
196/*
197** this macro can be used by some `history' system to save lines
198** read in manual input
199*/
200#ifndef lua_saveline
201#define lua_saveline(L,line) /* empty */
202#endif
203
204
205/*
206** this macro defines a function to show the prompt and reads the
207** next line for manual input
208*/
209#ifndef lua_readline
210#define lua_readline(L,prompt) readline(L,prompt)
211
212/* maximum length of an input line */
213#ifndef MAXINPUT
214#define MAXINPUT 512
215#endif
216
217
218static int readline (lua_State *l, const char *prompt) {
219 static char buffer[MAXINPUT];
220 if (prompt) {
221 fputs(prompt, stdout);
222 fflush(stdout);
223 }
224 if (fgets(buffer, sizeof(buffer), stdin) == NULL)
225 return 0; /* read fails */
226 else {
227 lua_pushstring(l, buffer);
228 return 1;
229 }
230}
231
232#endif
233
234
235static const char *get_prompt (int firstline) {
236 const char *p = NULL;
237 lua_pushstring(L, firstline ? "_PROMPT" : "_PROMPT2");
238 lua_rawget(L, LUA_GLOBALSINDEX);
239 p = lua_tostring(L, -1);
240 if (p == NULL) p = (firstline ? PROMPT : PROMPT2);
241 lua_pop(L, 1); /* remove global */
242 return p;
243}
244
245
246static int incomplete (int status) {
247 if (status == LUA_ERRSYNTAX &&
248 strstr(lua_tostring(L, -1), "near `<eof>'") != NULL) {
249 lua_pop(L, 1);
250 return 1;
251 }
252 else
253 return 0;
254}
255
256
257static int load_string (void) {
258 int status;
259 lua_settop(L, 0);
260 if (lua_readline(L, get_prompt(1)) == 0) /* no input? */
261 return -1;
262 if (lua_tostring(L, -1)[0] == '=') { /* line starts with `=' ? */
263 lua_pushfstring(L, "return %s", lua_tostring(L, -1)+1);/* `=' -> `return' */
264 lua_remove(L, -2); /* remove original line */
265 }
266 for (;;) { /* repeat until gets a complete line */
267 status = luaL_loadbuffer(L, lua_tostring(L, 1), lua_strlen(L, 1), "=stdin");
268 if (!incomplete(status)) break; /* cannot try to add lines? */
269 if (lua_readline(L, get_prompt(0)) == 0) /* no more input? */
270 return -1;
271 lua_concat(L, lua_gettop(L)); /* join lines */
272 }
273 lua_saveline(L, lua_tostring(L, 1));
274 lua_remove(L, 1); /* remove line */
275 return status;
276}
277
278
279static void manual_input (void) {
280 int status;
281 const char *oldprogname = progname;
282 progname = NULL;
283 while ((status = load_string()) != -1) {
284 if (status == 0) status = lcall(0, 0);
285 report(status);
286 if (status == 0 && lua_gettop(L) > 0) { /* any result to print? */
287 lua_getglobal(L, "print");
288 lua_insert(L, 1);
289 if (lua_pcall(L, lua_gettop(L)-1, 0, 0) != 0)
290 l_message(progname, lua_pushfstring(L, "error calling `print' (%s)",
291 lua_tostring(L, -1)));
292 }
293 }
294 lua_settop(L, 0); /* clear stack */
295 fputs("\n", stdout);
296 progname = oldprogname;
297}
298
299
300static int handle_argv (char *argv[], int *interactive) {
301 if (argv[1] == NULL) { /* no more arguments? */
302 if (stdin_is_tty()) {
303 print_version();
304 manual_input();
305 }
306 else
307 file_input(NULL); /* executes stdin as a file */
308 }
309 else { /* other arguments; loop over them */
310 int i;
311 for (i = 1; argv[i] != NULL; i++) {
312 if (argv[i][0] != '-') break; /* not an option? */
313 switch (argv[i][1]) { /* option */
314 case '-': { /* `--' */
315 if (argv[i][2] != '\0') {
316 print_usage();
317 return 1;
318 }
319 i++; /* skip this argument */
320 goto endloop; /* stop handling arguments */
321 }
322 case '\0': {
323 file_input(NULL); /* executes stdin as a file */
324 break;
325 }
326 case 'i': {
327 *interactive = 1;
328 break;
329 }
330 case 'v': {
331 print_version();
332 break;
333 }
334 case 'e': {
335 const char *chunk = argv[i] + 2;
336 if (*chunk == '\0') chunk = argv[++i];
337 if (chunk == NULL) {
338 print_usage();
339 return 1;
340 }
341 if (dostring(chunk, "=<command line>") != 0)
342 return 1;
343 break;
344 }
345 case 'l': {
346 const char *filename = argv[i] + 2;
347 if (*filename == '\0') filename = argv[++i];
348 if (filename == NULL) {
349 print_usage();
350 return 1;
351 }
352 if (load_file(filename))
353 return 1; /* stop if file fails */
354 break;
355 }
356 case 'c': {
357 l_message(progname, "option `-c' is deprecated");
358 break;
359 }
360 case 's': {
361 l_message(progname, "option `-s' is deprecated");
362 break;
363 }
364 default: {
365 print_usage();
366 return 1;
367 }
368 }
369 } endloop:
370 if (argv[i] != NULL) {
371 const char *filename = argv[i];
372 getargs(argv, i); /* collect arguments */
373 lua_setglobal(L, "arg");
374 return file_input(filename); /* stop scanning arguments */
375 }
376 }
377 return 0;
378}
379
380
381static void openstdlibs (lua_State *l) {
382 const luaL_reg *lib = lualibs;
383 for (; lib->func; lib++) {
384 lib->func(l); /* open library */
385 lua_settop(l, 0); /* discard any results */
386 }
387}
388
389
390static int handle_luainit (void) {
391 const char *init = getenv("LUA_INIT");
392 if (init == NULL) return 0; /* status OK */
393 else if (init[0] == '@')
394 return file_input(init+1);
395 else
396 return dostring(init, "=LUA_INIT");
397}
398
399
400struct Smain {
401 int argc;
402 char **argv;
403 int status;
404};
405
406
407static int pmain (lua_State *l) {
408 struct Smain *s = (struct Smain *)lua_touserdata(l, 1);
409 int status;
410 int interactive = 0;
411 if (s->argv[0] && s->argv[0][0]) progname = s->argv[0];
412 L = l;
413 lua_userinit(l); /* open libraries */
414 status = handle_luainit();
415 if (status == 0) {
416 status = handle_argv(s->argv, &interactive);
417 if (status == 0 && interactive) manual_input();
418 }
419 s->status = status;
420 return 0;
421}
422
423
424int main (int argc, char *argv[]) {
425 int status;
426 struct Smain s;
427 lua_State *l = lua_open(); /* create state */
428 if (l == NULL) {
429 l_message(argv[0], "cannot create state: not enough memory");
430 return EXIT_FAILURE;
431 }
432 s.argc = argc;
433 s.argv = argv;
434 status = lua_cpcall(l, &pmain, &s);
435 report(status);
436 lua_close(l);
437 return (status || s.status) ? EXIT_FAILURE : EXIT_SUCCESS;
438}
439