1 /* 2 ** $Id: liolib.c,v 2.111 2013/03/21 13:57:27 roberto Exp $ 3 ** Standard I/O (and system) library 4 ** See Copyright Notice in lua.h 5 */ 6 7 8 /* 9 ** POSIX idiosyncrasy! 10 ** This definition must come before the inclusion of 'stdio.h'; it 11 ** should not affect non-POSIX systems 12 */ 13 #if !defined(_FILE_OFFSET_BITS) 14 #define _FILE_OFFSET_BITS 64 15 #endif 16 17 18 #include <errno.h> 19 #include <stdio.h> 20 #include <stdlib.h> 21 #include <string.h> 22 23 #define liolib_c 24 #define LUA_LIB 25 26 #include "lua.h" 27 28 #include "lauxlib.h" 29 #include "lualib.h" 30 31 32 #if !defined(lua_checkmode) 33 34 /* 35 ** Check whether 'mode' matches '[rwa]%+?b?'. 36 ** Change this macro to accept other modes for 'fopen' besides 37 ** the standard ones. 38 */ 39 #define lua_checkmode(mode) \ 40 (*mode != '\0' && strchr("rwa", *(mode++)) != NULL && \ 41 (*mode != '+' || ++mode) && /* skip if char is '+' */ \ 42 (*mode != 'b' || ++mode) && /* skip if char is 'b' */ \ 43 (*mode == '\0')) 44 45 #endif 46 47 /* 48 ** {====================================================== 49 ** lua_popen spawns a new process connected to the current 50 ** one through the file streams. 51 ** ======================================================= 52 */ 53 54 #if !defined(lua_popen) /* { */ 55 56 #if defined(LUA_USE_POPEN) /* { */ 57 58 #define lua_popen(L,c,m) ((void)L, fflush(NULL), popen(c,m)) 59 #define lua_pclose(L,file) ((void)L, pclose(file)) 60 61 #elif defined(LUA_WIN) /* }{ */ 62 63 #define lua_popen(L,c,m) ((void)L, _popen(c,m)) 64 #define lua_pclose(L,file) ((void)L, _pclose(file)) 65 66 67 #else /* }{ */ 68 69 #define lua_popen(L,c,m) ((void)((void)c, m), \ 70 luaL_error(L, LUA_QL("popen") " not supported"), (FILE*)0) 71 #define lua_pclose(L,file) ((void)((void)L, file), -1) 72 73 74 #endif /* } */ 75 76 #endif /* } */ 77 78 /* }====================================================== */ 79 80 81 /* 82 ** {====================================================== 83 ** lua_fseek/lua_ftell: configuration for longer offsets 84 ** ======================================================= 85 */ 86 87 #if !defined(lua_fseek) /* { */ 88 89 #if defined(LUA_USE_POSIX) 90 91 #define l_fseek(f,o,w) fseeko(f,o,w) 92 #define l_ftell(f) ftello(f) 93 #define l_seeknum off_t 94 95 #elif defined(LUA_WIN) && !defined(_CRTIMP_TYPEINFO) \ 96 && defined(_MSC_VER) && (_MSC_VER >= 1400) 97 /* Windows (but not DDK) and Visual C++ 2005 or higher */ 98 99 #define l_fseek(f,o,w) _fseeki64(f,o,w) 100 #define l_ftell(f) _ftelli64(f) 101 #define l_seeknum __int64 102 103 #else 104 105 #define l_fseek(f,o,w) fseek(f,o,w) 106 #define l_ftell(f) ftell(f) 107 #define l_seeknum long 108 109 #endif 110 111 #endif /* } */ 112 113 /* }====================================================== */ 114 115 116 #define IO_PREFIX "_IO_" 117 #define IO_INPUT (IO_PREFIX "input") 118 #define IO_OUTPUT (IO_PREFIX "output") 119 120 121 typedef luaL_Stream LStream; 122 123 124 #define tolstream(L) ((LStream *)luaL_checkudata(L, 1, LUA_FILEHANDLE)) 125 126 #define isclosed(p) ((p)->closef == NULL) 127 128 129 static int io_type (lua_State *L) { 130 LStream *p; 131 luaL_checkany(L, 1); 132 p = (LStream *)luaL_testudata(L, 1, LUA_FILEHANDLE); 133 if (p == NULL) 134 lua_pushnil(L); /* not a file */ 135 else if (isclosed(p)) 136 lua_pushliteral(L, "closed file"); 137 else 138 lua_pushliteral(L, "file"); 139 return 1; 140 } 141 142 143 static int f_tostring (lua_State *L) { 144 LStream *p = tolstream(L); 145 if (isclosed(p)) 146 lua_pushliteral(L, "file (closed)"); 147 else 148 lua_pushfstring(L, "file (%p)", p->f); 149 return 1; 150 } 151 152 153 static FILE *tofile (lua_State *L) { 154 LStream *p = tolstream(L); 155 if (isclosed(p)) 156 luaL_error(L, "attempt to use a closed file"); 157 lua_assert(p->f); 158 return p->f; 159 } 160 161 162 /* 163 ** When creating file handles, always creates a `closed' file handle 164 ** before opening the actual file; so, if there is a memory error, the 165 ** file is not left opened. 166 */ 167 static LStream *newprefile (lua_State *L) { 168 LStream *p = (LStream *)lua_newuserdata(L, sizeof(LStream)); 169 p->closef = NULL; /* mark file handle as 'closed' */ 170 luaL_setmetatable(L, LUA_FILEHANDLE); 171 return p; 172 } 173 174 175 static int aux_close (lua_State *L) { 176 LStream *p = tolstream(L); 177 lua_CFunction cf = p->closef; 178 p->closef = NULL; /* mark stream as closed */ 179 return (*cf)(L); /* close it */ 180 } 181 182 183 static int io_close (lua_State *L) { 184 if (lua_isnone(L, 1)) /* no argument? */ 185 lua_getfield(L, LUA_REGISTRYINDEX, IO_OUTPUT); /* use standard output */ 186 tofile(L); /* make sure argument is an open stream */ 187 return aux_close(L); 188 } 189 190 191 static int f_gc (lua_State *L) { 192 LStream *p = tolstream(L); 193 if (!isclosed(p) && p->f != NULL) 194 aux_close(L); /* ignore closed and incompletely open files */ 195 return 0; 196 } 197 198 199 /* 200 ** function to close regular files 201 */ 202 static int io_fclose (lua_State *L) { 203 LStream *p = tolstream(L); 204 int res = fclose(p->f); 205 return luaL_fileresult(L, (res == 0), NULL); 206 } 207 208 209 static LStream *newfile (lua_State *L) { 210 LStream *p = newprefile(L); 211 p->f = NULL; 212 p->closef = &io_fclose; 213 return p; 214 } 215 216 217 static void opencheck (lua_State *L, const char *fname, const char *mode) { 218 LStream *p = newfile(L); 219 p->f = fopen(fname, mode); 220 if (p->f == NULL) 221 luaL_error(L, "cannot open file " LUA_QS " (%s)", fname, strerror(errno)); 222 } 223 224 225 static int io_open (lua_State *L) { 226 const char *filename = luaL_checkstring(L, 1); 227 const char *mode = luaL_optstring(L, 2, "r"); 228 LStream *p = newfile(L); 229 const char *md = mode; /* to traverse/check mode */ 230 luaL_argcheck(L, lua_checkmode(md), 2, "invalid mode"); 231 p->f = fopen(filename, mode); 232 return (p->f == NULL) ? luaL_fileresult(L, 0, filename) : 1; 233 } 234 235 236 /* 237 ** function to close 'popen' files 238 */ 239 static int io_pclose (lua_State *L) { 240 LStream *p = tolstream(L); 241 return luaL_execresult(L, lua_pclose(L, p->f)); 242 } 243 244 245 static int io_popen (lua_State *L) { 246 const char *filename = luaL_checkstring(L, 1); 247 const char *mode = luaL_optstring(L, 2, "r"); 248 LStream *p = newprefile(L); 249 p->f = lua_popen(L, filename, mode); 250 p->closef = &io_pclose; 251 return (p->f == NULL) ? luaL_fileresult(L, 0, filename) : 1; 252 } 253 254 255 static int io_tmpfile (lua_State *L) { 256 LStream *p = newfile(L); 257 p->f = tmpfile(); 258 return (p->f == NULL) ? luaL_fileresult(L, 0, NULL) : 1; 259 } 260 261 262 static FILE *getiofile (lua_State *L, const char *findex) { 263 LStream *p; 264 lua_getfield(L, LUA_REGISTRYINDEX, findex); 265 p = (LStream *)lua_touserdata(L, -1); 266 if (isclosed(p)) 267 luaL_error(L, "standard %s file is closed", findex + strlen(IO_PREFIX)); 268 return p->f; 269 } 270 271 272 static int g_iofile (lua_State *L, const char *f, const char *mode) { 273 if (!lua_isnoneornil(L, 1)) { 274 const char *filename = lua_tostring(L, 1); 275 if (filename) 276 opencheck(L, filename, mode); 277 else { 278 tofile(L); /* check that it's a valid file handle */ 279 lua_pushvalue(L, 1); 280 } 281 lua_setfield(L, LUA_REGISTRYINDEX, f); 282 } 283 /* return current value */ 284 lua_getfield(L, LUA_REGISTRYINDEX, f); 285 return 1; 286 } 287 288 289 static int io_input (lua_State *L) { 290 return g_iofile(L, IO_INPUT, "r"); 291 } 292 293 294 static int io_output (lua_State *L) { 295 return g_iofile(L, IO_OUTPUT, "w"); 296 } 297 298 299 static int io_readline (lua_State *L); 300 301 302 static void aux_lines (lua_State *L, int toclose) { 303 int i; 304 int n = lua_gettop(L) - 1; /* number of arguments to read */ 305 /* ensure that arguments will fit here and into 'io_readline' stack */ 306 luaL_argcheck(L, n <= LUA_MINSTACK - 3, LUA_MINSTACK - 3, "too many options"); 307 lua_pushvalue(L, 1); /* file handle */ 308 lua_pushinteger(L, n); /* number of arguments to read */ 309 lua_pushboolean(L, toclose); /* close/not close file when finished */ 310 for (i = 1; i <= n; i++) lua_pushvalue(L, i + 1); /* copy arguments */ 311 lua_pushcclosure(L, io_readline, 3 + n); 312 } 313 314 315 static int f_lines (lua_State *L) { 316 tofile(L); /* check that it's a valid file handle */ 317 aux_lines(L, 0); 318 return 1; 319 } 320 321 322 static int io_lines (lua_State *L) { 323 int toclose; 324 if (lua_isnone(L, 1)) lua_pushnil(L); /* at least one argument */ 325 if (lua_isnil(L, 1)) { /* no file name? */ 326 lua_getfield(L, LUA_REGISTRYINDEX, IO_INPUT); /* get default input */ 327 lua_replace(L, 1); /* put it at index 1 */ 328 tofile(L); /* check that it's a valid file handle */ 329 toclose = 0; /* do not close it after iteration */ 330 } 331 else { /* open a new file */ 332 const char *filename = luaL_checkstring(L, 1); 333 opencheck(L, filename, "r"); 334 lua_replace(L, 1); /* put file at index 1 */ 335 toclose = 1; /* close it after iteration */ 336 } 337 aux_lines(L, toclose); 338 return 1; 339 } 340 341 342 /* 343 ** {====================================================== 344 ** READ 345 ** ======================================================= 346 */ 347 348 349 static int read_number (lua_State *L, FILE *f) { 350 lua_Number d; 351 if (fscanf(f, LUA_NUMBER_SCAN, &d) == 1) { 352 lua_pushnumber(L, d); 353 return 1; 354 } 355 else { 356 lua_pushnil(L); /* "result" to be removed */ 357 return 0; /* read fails */ 358 } 359 } 360 361 362 static int test_eof (lua_State *L, FILE *f) { 363 int c = getc(f); 364 ungetc(c, f); 365 lua_pushlstring(L, NULL, 0); 366 return (c != EOF); 367 } 368 369 370 static int read_line (lua_State *L, FILE *f, int chop) { 371 luaL_Buffer b; 372 luaL_buffinit(L, &b); 373 for (;;) { 374 size_t l; 375 char *p = luaL_prepbuffer(&b); 376 if (fgets(p, LUAL_BUFFERSIZE, f) == NULL) { /* eof? */ 377 luaL_pushresult(&b); /* close buffer */ 378 return (lua_rawlen(L, -1) > 0); /* check whether read something */ 379 } 380 l = strlen(p); 381 if (l == 0 || p[l-1] != '\n') 382 luaL_addsize(&b, l); 383 else { 384 luaL_addsize(&b, l - chop); /* chop 'eol' if needed */ 385 luaL_pushresult(&b); /* close buffer */ 386 return 1; /* read at least an `eol' */ 387 } 388 } 389 } 390 391 392 #define MAX_SIZE_T (~(size_t)0) 393 394 static void read_all (lua_State *L, FILE *f) { 395 size_t rlen = LUAL_BUFFERSIZE; /* how much to read in each cycle */ 396 luaL_Buffer b; 397 luaL_buffinit(L, &b); 398 for (;;) { 399 char *p = luaL_prepbuffsize(&b, rlen); 400 size_t nr = fread(p, sizeof(char), rlen, f); 401 luaL_addsize(&b, nr); 402 if (nr < rlen) break; /* eof? */ 403 else if (rlen <= (MAX_SIZE_T / 4)) /* avoid buffers too large */ 404 rlen *= 2; /* double buffer size at each iteration */ 405 } 406 luaL_pushresult(&b); /* close buffer */ 407 } 408 409 410 static int read_chars (lua_State *L, FILE *f, size_t n) { 411 size_t nr; /* number of chars actually read */ 412 char *p; 413 luaL_Buffer b; 414 luaL_buffinit(L, &b); 415 p = luaL_prepbuffsize(&b, n); /* prepare buffer to read whole block */ 416 nr = fread(p, sizeof(char), n, f); /* try to read 'n' chars */ 417 luaL_addsize(&b, nr); 418 luaL_pushresult(&b); /* close buffer */ 419 return (nr > 0); /* true iff read something */ 420 } 421 422 423 static int g_read (lua_State *L, FILE *f, int first) { 424 int nargs = lua_gettop(L) - 1; 425 int success; 426 int n; 427 clearerr(f); 428 if (nargs == 0) { /* no arguments? */ 429 success = read_line(L, f, 1); 430 n = first+1; /* to return 1 result */ 431 } 432 else { /* ensure stack space for all results and for auxlib's buffer */ 433 luaL_checkstack(L, nargs+LUA_MINSTACK, "too many arguments"); 434 success = 1; 435 for (n = first; nargs-- && success; n++) { 436 if (lua_type(L, n) == LUA_TNUMBER) { 437 size_t l = (size_t)lua_tointeger(L, n); 438 success = (l == 0) ? test_eof(L, f) : read_chars(L, f, l); 439 } 440 else { 441 const char *p = lua_tostring(L, n); 442 luaL_argcheck(L, p && p[0] == '*', n, "invalid option"); 443 switch (p[1]) { 444 case 'n': /* number */ 445 success = read_number(L, f); 446 break; 447 case 'l': /* line */ 448 success = read_line(L, f, 1); 449 break; 450 case 'L': /* line with end-of-line */ 451 success = read_line(L, f, 0); 452 break; 453 case 'a': /* file */ 454 read_all(L, f); /* read entire file */ 455 success = 1; /* always success */ 456 break; 457 default: 458 return luaL_argerror(L, n, "invalid format"); 459 } 460 } 461 } 462 } 463 if (ferror(f)) 464 return luaL_fileresult(L, 0, NULL); 465 if (!success) { 466 lua_pop(L, 1); /* remove last result */ 467 lua_pushnil(L); /* push nil instead */ 468 } 469 return n - first; 470 } 471 472 473 static int io_read (lua_State *L) { 474 return g_read(L, getiofile(L, IO_INPUT), 1); 475 } 476 477 478 static int f_read (lua_State *L) { 479 return g_read(L, tofile(L), 2); 480 } 481 482 483 static int io_readline (lua_State *L) { 484 LStream *p = (LStream *)lua_touserdata(L, lua_upvalueindex(1)); 485 int i; 486 int n = (int)lua_tointeger(L, lua_upvalueindex(2)); 487 if (isclosed(p)) /* file is already closed? */ 488 return luaL_error(L, "file is already closed"); 489 lua_settop(L , 1); 490 for (i = 1; i <= n; i++) /* push arguments to 'g_read' */ 491 lua_pushvalue(L, lua_upvalueindex(3 + i)); 492 n = g_read(L, p->f, 2); /* 'n' is number of results */ 493 lua_assert(n > 0); /* should return at least a nil */ 494 if (!lua_isnil(L, -n)) /* read at least one value? */ 495 return n; /* return them */ 496 else { /* first result is nil: EOF or error */ 497 if (n > 1) { /* is there error information? */ 498 /* 2nd result is error message */ 499 return luaL_error(L, "%s", lua_tostring(L, -n + 1)); 500 } 501 if (lua_toboolean(L, lua_upvalueindex(3))) { /* generator created file? */ 502 lua_settop(L, 0); 503 lua_pushvalue(L, lua_upvalueindex(1)); 504 aux_close(L); /* close it */ 505 } 506 return 0; 507 } 508 } 509 510 /* }====================================================== */ 511 512 513 static int g_write (lua_State *L, FILE *f, int arg) { 514 int nargs = lua_gettop(L) - arg; 515 int status = 1; 516 for (; nargs--; arg++) { 517 if (lua_type(L, arg) == LUA_TNUMBER) { 518 /* optimization: could be done exactly as for strings */ 519 status = status && 520 fprintf(f, LUA_NUMBER_FMT, lua_tonumber(L, arg)) > 0; 521 } 522 else { 523 size_t l; 524 const char *s = luaL_checklstring(L, arg, &l); 525 status = status && (fwrite(s, sizeof(char), l, f) == l); 526 } 527 } 528 if (status) return 1; /* file handle already on stack top */ 529 else return luaL_fileresult(L, status, NULL); 530 } 531 532 533 static int io_write (lua_State *L) { 534 return g_write(L, getiofile(L, IO_OUTPUT), 1); 535 } 536 537 538 static int f_write (lua_State *L) { 539 FILE *f = tofile(L); 540 lua_pushvalue(L, 1); /* push file at the stack top (to be returned) */ 541 return g_write(L, f, 2); 542 } 543 544 545 static int f_seek (lua_State *L) { 546 static const int mode[] = {SEEK_SET, SEEK_CUR, SEEK_END}; 547 static const char *const modenames[] = {"set", "cur", "end", NULL}; 548 FILE *f = tofile(L); 549 int op = luaL_checkoption(L, 2, "cur", modenames); 550 lua_Number p3 = luaL_optnumber(L, 3, 0); 551 l_seeknum offset = (l_seeknum)p3; 552 luaL_argcheck(L, (lua_Number)offset == p3, 3, 553 "not an integer in proper range"); 554 op = l_fseek(f, offset, mode[op]); 555 if (op) 556 return luaL_fileresult(L, 0, NULL); /* error */ 557 else { 558 lua_pushnumber(L, (lua_Number)l_ftell(f)); 559 return 1; 560 } 561 } 562 563 564 static int f_setvbuf (lua_State *L) { 565 static const int mode[] = {_IONBF, _IOFBF, _IOLBF}; 566 static const char *const modenames[] = {"no", "full", "line", NULL}; 567 FILE *f = tofile(L); 568 int op = luaL_checkoption(L, 2, NULL, modenames); 569 lua_Integer sz = luaL_optinteger(L, 3, LUAL_BUFFERSIZE); 570 int res = setvbuf(f, NULL, mode[op], sz); 571 return luaL_fileresult(L, res == 0, NULL); 572 } 573 574 575 576 static int io_flush (lua_State *L) { 577 return luaL_fileresult(L, fflush(getiofile(L, IO_OUTPUT)) == 0, NULL); 578 } 579 580 581 static int f_flush (lua_State *L) { 582 return luaL_fileresult(L, fflush(tofile(L)) == 0, NULL); 583 } 584 585 586 /* 587 ** functions for 'io' library 588 */ 589 static const luaL_Reg iolib[] = { 590 {"close", io_close}, 591 {"flush", io_flush}, 592 {"input", io_input}, 593 {"lines", io_lines}, 594 {"open", io_open}, 595 {"output", io_output}, 596 {"popen", io_popen}, 597 {"read", io_read}, 598 {"tmpfile", io_tmpfile}, 599 {"type", io_type}, 600 {"write", io_write}, 601 {NULL, NULL} 602 }; 603 604 605 /* 606 ** methods for file handles 607 */ 608 static const luaL_Reg flib[] = { 609 {"close", io_close}, 610 {"flush", f_flush}, 611 {"lines", f_lines}, 612 {"read", f_read}, 613 {"seek", f_seek}, 614 {"setvbuf", f_setvbuf}, 615 {"write", f_write}, 616 {"__gc", f_gc}, 617 {"__tostring", f_tostring}, 618 {NULL, NULL} 619 }; 620 621 622 static void createmeta (lua_State *L) { 623 luaL_newmetatable(L, LUA_FILEHANDLE); /* create metatable for file handles */ 624 lua_pushvalue(L, -1); /* push metatable */ 625 lua_setfield(L, -2, "__index"); /* metatable.__index = metatable */ 626 luaL_setfuncs(L, flib, 0); /* add file methods to new metatable */ 627 lua_pop(L, 1); /* pop new metatable */ 628 } 629 630 631 /* 632 ** function to (not) close the standard files stdin, stdout, and stderr 633 */ 634 static int io_noclose (lua_State *L) { 635 LStream *p = tolstream(L); 636 p->closef = &io_noclose; /* keep file opened */ 637 lua_pushnil(L); 638 lua_pushliteral(L, "cannot close standard file"); 639 return 2; 640 } 641 642 643 static void createstdfile (lua_State *L, FILE *f, const char *k, 644 const char *fname) { 645 LStream *p = newprefile(L); 646 p->f = f; 647 p->closef = &io_noclose; 648 if (k != NULL) { 649 lua_pushvalue(L, -1); 650 lua_setfield(L, LUA_REGISTRYINDEX, k); /* add file to registry */ 651 } 652 lua_setfield(L, -2, fname); /* add file to module */ 653 } 654 655 656 LUAMOD_API int luaopen_io (lua_State *L) { 657 luaL_newlib(L, iolib); /* new module */ 658 createmeta(L); 659 /* create (and set) default files */ 660 createstdfile(L, stdin, IO_INPUT, "stdin"); 661 createstdfile(L, stdout, IO_OUTPUT, "stdout"); 662 createstdfile(L, stderr, NULL, "stderr"); 663 return 1; 664 } 665 666
