| 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 | |