/script_binding/lua/lua/lua.c
C | 392 lines | 323 code | 61 blank | 8 comment | 100 complexity | 50502857aab32e8a1886b491b3fe1ddb MD5 | raw file
1/* 2** $Id: lua.c,v 1.160.1.2 2007/12/28 15:32:23 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 22static lua_State *globalL = NULL; 23 24static const char *progname = LUA_PROGNAME; 25 26 27 28static void lstop (lua_State *L, lua_Debug *ar) { 29 (void)ar; /* unused arg. */ 30 lua_sethook(L, NULL, 0, 0); 31 luaL_error(L, "interrupted!"); 32} 33 34 35static void laction (int i) { 36 signal(i, SIG_DFL); /* if another SIGINT happens before lstop, 37 terminate process (default action) */ 38 lua_sethook(globalL, lstop, LUA_MASKCALL | LUA_MASKRET | LUA_MASKCOUNT, 1); 39} 40 41 42static void print_usage (void) { 43 fprintf(stderr, 44 "usage: %s [options] [script [args]].\n" 45 "Available options are:\n" 46 " -e stat execute string " LUA_QL("stat") "\n" 47 " -l name require library " LUA_QL("name") "\n" 48 " -i enter interactive mode after executing " LUA_QL("script") "\n" 49 " -v show version information\n" 50 " -- stop handling options\n" 51 " - execute stdin and stop handling options\n" 52 , 53 progname); 54 fflush(stderr); 55} 56 57 58static void l_message (const char *pname, const char *msg) { 59 if (pname) fprintf(stderr, "%s: ", pname); 60 fprintf(stderr, "%s\n", msg); 61 fflush(stderr); 62} 63 64 65static int report (lua_State *L, int status) { 66 if (status && !lua_isnil(L, -1)) { 67 const char *msg = lua_tostring(L, -1); 68 if (msg == NULL) msg = "(error object is not a string)"; 69 l_message(progname, msg); 70 lua_pop(L, 1); 71 } 72 return status; 73} 74 75 76static int traceback (lua_State *L) { 77 if (!lua_isstring(L, 1)) /* 'message' not a string? */ 78 return 1; /* keep it intact */ 79 lua_getfield(L, LUA_GLOBALSINDEX, "debug"); 80 if (!lua_istable(L, -1)) { 81 lua_pop(L, 1); 82 return 1; 83 } 84 lua_getfield(L, -1, "traceback"); 85 if (!lua_isfunction(L, -1)) { 86 lua_pop(L, 2); 87 return 1; 88 } 89 lua_pushvalue(L, 1); /* pass error message */ 90 lua_pushinteger(L, 2); /* skip this function and traceback */ 91 lua_call(L, 2, 1); /* call debug.traceback */ 92 return 1; 93} 94 95 96static int docall (lua_State *L, int narg, int clear) { 97 int status; 98 int base = lua_gettop(L) - narg; /* function index */ 99 lua_pushcfunction(L, traceback); /* push traceback function */ 100 lua_insert(L, base); /* put it under chunk and args */ 101 signal(SIGINT, laction); 102 status = lua_pcall(L, narg, (clear ? 0 : LUA_MULTRET), base); 103 signal(SIGINT, SIG_DFL); 104 lua_remove(L, base); /* remove traceback function */ 105 /* force a complete garbage collection in case of errors */ 106 if (status != 0) lua_gc(L, LUA_GCCOLLECT, 0); 107 return status; 108} 109 110 111static void print_version (void) { 112 l_message(NULL, LUA_RELEASE " " LUA_COPYRIGHT); 113} 114 115 116static int getargs (lua_State *L, char **argv, int n) { 117 int narg; 118 int i; 119 int argc = 0; 120 while (argv[argc]) argc++; /* count total number of arguments */ 121 narg = argc - (n + 1); /* number of arguments to the script */ 122 luaL_checkstack(L, narg + 3, "too many arguments to script"); 123 for (i=n+1; i < argc; i++) 124 lua_pushstring(L, argv[i]); 125 lua_createtable(L, narg, n + 1); 126 for (i=0; i < argc; i++) { 127 lua_pushstring(L, argv[i]); 128 lua_rawseti(L, -2, i - n); 129 } 130 return narg; 131} 132 133 134static int dofile (lua_State *L, const char *name) { 135 int status = luaL_loadfile(L, name) || docall(L, 0, 1); 136 return report(L, status); 137} 138 139 140static int dostring (lua_State *L, const char *s, const char *name) { 141 int status = luaL_loadbuffer(L, s, strlen(s), name) || docall(L, 0, 1); 142 return report(L, status); 143} 144 145 146static int dolibrary (lua_State *L, const char *name) { 147 lua_getglobal(L, "require"); 148 lua_pushstring(L, name); 149 return report(L, docall(L, 1, 1)); 150} 151 152 153static const char *get_prompt (lua_State *L, int firstline) { 154 const char *p; 155 lua_getfield(L, LUA_GLOBALSINDEX, firstline ? "_PROMPT" : "_PROMPT2"); 156 p = lua_tostring(L, -1); 157 if (p == NULL) p = (firstline ? LUA_PROMPT : LUA_PROMPT2); 158 lua_pop(L, 1); /* remove global */ 159 return p; 160} 161 162 163static int incomplete (lua_State *L, int status) { 164 if (status == LUA_ERRSYNTAX) { 165 size_t lmsg; 166 const char *msg = lua_tolstring(L, -1, &lmsg); 167 const char *tp = msg + lmsg - (sizeof(LUA_QL("<eof>")) - 1); 168 if (strstr(msg, LUA_QL("<eof>")) == tp) { 169 lua_pop(L, 1); 170 return 1; 171 } 172 } 173 return 0; /* else... */ 174} 175 176 177static int pushline (lua_State *L, int firstline) { 178 char buffer[LUA_MAXINPUT]; 179 char *b = buffer; 180 size_t l; 181 const char *prmt = get_prompt(L, firstline); 182 if (lua_readline(L, b, prmt) == 0) 183 return 0; /* no input */ 184 l = strlen(b); 185 if (l > 0 && b[l-1] == '\n') /* line ends with newline? */ 186 b[l-1] = '\0'; /* remove it */ 187 if (firstline && b[0] == '=') /* first line starts with `=' ? */ 188 lua_pushfstring(L, "return %s", b+1); /* change it to `return' */ 189 else 190 lua_pushstring(L, b); 191 lua_freeline(L, b); 192 return 1; 193} 194 195 196static int loadline (lua_State *L) { 197 int status; 198 lua_settop(L, 0); 199 if (!pushline(L, 1)) 200 return -1; /* no input */ 201 for (;;) { /* repeat until gets a complete line */ 202 status = luaL_loadbuffer(L, lua_tostring(L, 1), lua_strlen(L, 1), "=stdin"); 203 if (!incomplete(L, status)) break; /* cannot try to add lines? */ 204 if (!pushline(L, 0)) /* no more input? */ 205 return -1; 206 lua_pushliteral(L, "\n"); /* add a new line... */ 207 lua_insert(L, -2); /* ...between the two lines */ 208 lua_concat(L, 3); /* join them */ 209 } 210 lua_saveline(L, 1); 211 lua_remove(L, 1); /* remove line */ 212 return status; 213} 214 215 216static void dotty (lua_State *L) { 217 int status; 218 const char *oldprogname = progname; 219 progname = NULL; 220 while ((status = loadline(L)) != -1) { 221 if (status == 0) status = docall(L, 0, 0); 222 report(L, status); 223 if (status == 0 && lua_gettop(L) > 0) { /* any result to print? */ 224 lua_getglobal(L, "print"); 225 lua_insert(L, 1); 226 if (lua_pcall(L, lua_gettop(L)-1, 0, 0) != 0) 227 l_message(progname, lua_pushfstring(L, 228 "error calling " LUA_QL("print") " (%s)", 229 lua_tostring(L, -1))); 230 } 231 } 232 lua_settop(L, 0); /* clear stack */ 233 fputs("\n", stdout); 234 fflush(stdout); 235 progname = oldprogname; 236} 237 238 239static int handle_script (lua_State *L, char **argv, int n) { 240 int status; 241 const char *fname; 242 int narg = getargs(L, argv, n); /* collect arguments */ 243 lua_setglobal(L, "arg"); 244 fname = argv[n]; 245 if (strcmp(fname, "-") == 0 && strcmp(argv[n-1], "--") != 0) 246 fname = NULL; /* stdin */ 247 status = luaL_loadfile(L, fname); 248 lua_insert(L, -(narg+1)); 249 if (status == 0) 250 status = docall(L, narg, 0); 251 else 252 lua_pop(L, narg); 253 return report(L, status); 254} 255 256 257/* check that argument has no extra characters at the end */ 258#define notail(x) {if ((x)[2] != '\0') return -1;} 259 260 261static int collectargs (char **argv, int *pi, int *pv, int *pe) { 262 int i; 263 for (i = 1; argv[i] != NULL; i++) { 264 if (argv[i][0] != '-') /* not an option? */ 265 return i; 266 switch (argv[i][1]) { /* option */ 267 case '-': 268 notail(argv[i]); 269 return (argv[i+1] != NULL ? i+1 : 0); 270 case '\0': 271 return i; 272 case 'i': 273 notail(argv[i]); 274 *pi = 1; /* go through */ 275 case 'v': 276 notail(argv[i]); 277 *pv = 1; 278 break; 279 case 'e': 280 *pe = 1; /* go through */ 281 case 'l': 282 if (argv[i][2] == '\0') { 283 i++; 284 if (argv[i] == NULL) return -1; 285 } 286 break; 287 default: return -1; /* invalid option */ 288 } 289 } 290 return 0; 291} 292 293 294static int runargs (lua_State *L, char **argv, int n) { 295 int i; 296 for (i = 1; i < n; i++) { 297 if (argv[i] == NULL) continue; 298 lua_assert(argv[i][0] == '-'); 299 switch (argv[i][1]) { /* option */ 300 case 'e': { 301 const char *chunk = argv[i] + 2; 302 if (*chunk == '\0') chunk = argv[++i]; 303 lua_assert(chunk != NULL); 304 if (dostring(L, chunk, "=(command line)") != 0) 305 return 1; 306 break; 307 } 308 case 'l': { 309 const char *filename = argv[i] + 2; 310 if (*filename == '\0') filename = argv[++i]; 311 lua_assert(filename != NULL); 312 if (dolibrary(L, filename)) 313 return 1; /* stop if file fails */ 314 break; 315 } 316 default: break; 317 } 318 } 319 return 0; 320} 321 322 323static int handle_luainit (lua_State *L) { 324 const char *init = getenv(LUA_INIT); 325 if (init == NULL) return 0; /* status OK */ 326 else if (init[0] == '@') 327 return dofile(L, init+1); 328 else 329 return dostring(L, init, "=" LUA_INIT); 330} 331 332 333struct Smain { 334 int argc; 335 char **argv; 336 int status; 337}; 338 339 340static int pmain (lua_State *L) { 341 struct Smain *s = (struct Smain *)lua_touserdata(L, 1); 342 char **argv = s->argv; 343 int script; 344 int has_i = 0, has_v = 0, has_e = 0; 345 globalL = L; 346 if (argv[0] && argv[0][0]) progname = argv[0]; 347 lua_gc(L, LUA_GCSTOP, 0); /* stop collector during initialization */ 348 luaL_openlibs(L); /* open libraries */ 349 lua_gc(L, LUA_GCRESTART, 0); 350 s->status = handle_luainit(L); 351 if (s->status != 0) return 0; 352 script = collectargs(argv, &has_i, &has_v, &has_e); 353 if (script < 0) { /* invalid args? */ 354 print_usage(); 355 s->status = 1; 356 return 0; 357 } 358 if (has_v) print_version(); 359 s->status = runargs(L, argv, (script > 0) ? script : s->argc); 360 if (s->status != 0) return 0; 361 if (script) 362 s->status = handle_script(L, argv, script); 363 if (s->status != 0) return 0; 364 if (has_i) 365 dotty(L); 366 else if (script == 0 && !has_e && !has_v) { 367 if (lua_stdin_is_tty()) { 368 print_version(); 369 dotty(L); 370 } 371 else dofile(L, NULL); /* executes stdin as a file */ 372 } 373 return 0; 374} 375 376 377int main (int argc, char **argv) { 378 int status; 379 struct Smain s; 380 lua_State *L = lua_open(); /* create state */ 381 if (L == NULL) { 382 l_message(argv[0], "cannot create state: not enough memory"); 383 return EXIT_FAILURE; 384 } 385 s.argc = argc; 386 s.argv = argv; 387 status = lua_cpcall(L, &pmain, &s); 388 report(L, status); 389 lua_close(L); 390 return (status || s.status) ? EXIT_FAILURE : EXIT_SUCCESS; 391} 392