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| 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 |
OLD | NEW |