client/deps/liblua/liolib.c

   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     } else { /* open a new file */
 331         const char *filename = luaL_checkstring(L, 1);
 332         opencheck(L, filename, "r");
 333         lua_replace(L, 1);  /* put file at index 1 */
 334         toclose = 1;  /* close it after iteration */
 335     }
 336     aux_lines(L, toclose);
 337     return 1;
 338 }
 339
 340
 341 /*
 342 ** {======================================================
 343 ** READ
 344 ** =======================================================
 345 */
 346
 347
 348 static int read_number(lua_State *L, FILE *f) {
 349     lua_Number d;
 350     if (fscanf(f, LUA_NUMBER_SCAN, &d) == 1) {
 351         lua_pushnumber(L, d);
 352         return 1;
 353     } else {
 354         lua_pushnil(L);  /* "result" to be removed */
 355         return 0;  /* read fails */
 356     }
 357 }
 358
 359
 360 static int test_eof(lua_State *L, FILE *f) {
 361     int c = getc(f);
 362     ungetc(c, f);
 363     lua_pushlstring(L, NULL, 0);
 364     return (c != EOF);
 365 }
 366
 367
 368 static int read_line(lua_State *L, FILE *f, int chop) {
 369     luaL_Buffer b;
 370     luaL_buffinit(L, &b);
 371     for (;;) {
 372         size_t l;
 373         char *p = luaL_prepbuffer(&b);
 374         if (fgets(p, LUAL_BUFFERSIZE, f) == NULL) {  /* eof? */
 375             luaL_pushresult(&b);  /* close buffer */
 376             return (lua_rawlen(L, -1) > 0);  /* check whether read something */
 377         }
 378         l = strlen(p);
 379         if (l == 0 || p[l - 1] != '\n')
 380             luaL_addsize(&b, l);
 381         else {
 382             luaL_addsize(&b, l - chop);  /* chop 'eol' if needed */
 383             luaL_pushresult(&b);  /* close buffer */
 384             return 1;  /* read at least an `eol' */
 385         }
 386     }
 387 }
 388
 389
 390 #define MAX_SIZE_T (~(size_t)0)
 391
 392 static void read_all(lua_State *L, FILE *f) {
 393     size_t rlen = LUAL_BUFFERSIZE;  /* how much to read in each cycle */
 394     luaL_Buffer b;
 395     luaL_buffinit(L, &b);
 396     for (;;) {
 397         char *p = luaL_prepbuffsize(&b, rlen);
 398         size_t nr = fread(p, sizeof(char), rlen, f);
 399         luaL_addsize(&b, nr);
 400         if (nr < rlen) break;  /* eof? */
 401         else if (rlen <= (MAX_SIZE_T / 4))  /* avoid buffers too large */
 402             rlen *= 2;  /* double buffer size at each iteration */
 403     }
 404     luaL_pushresult(&b);  /* close buffer */
 405 }
 406
 407
 408 static int read_chars(lua_State *L, FILE *f, size_t n) {
 409     size_t nr;  /* number of chars actually read */
 410     char *p;
 411     luaL_Buffer b;
 412     luaL_buffinit(L, &b);
 413     p = luaL_prepbuffsize(&b, n);  /* prepare buffer to read whole block */
 414     nr = fread(p, sizeof(char), n, f);  /* try to read 'n' chars */
 415     luaL_addsize(&b, nr);
 416     luaL_pushresult(&b);  /* close buffer */
 417     return (nr > 0);  /* true iff read something */
 418 }
 419
 420
 421 static int g_read(lua_State *L, FILE *f, int first) {
 422     int nargs = lua_gettop(L) - 1;
 423     int success;
 424     int n;
 425     clearerr(f);
 426     if (nargs == 0) {  /* no arguments? */
 427         success = read_line(L, f, 1);
 428         n = first + 1; /* to return 1 result */
 429     } else { /* ensure stack space for all results and for auxlib's buffer */
 430         luaL_checkstack(L, nargs + LUA_MINSTACK, "too many arguments");
 431         success = 1;
 432         for (n = first; nargs-- && success; n++) {
 433             if (lua_type(L, n) == LUA_TNUMBER) {
 434                 size_t l = (size_t)lua_tointeger(L, n);
 435                 success = (l == 0) ? test_eof(L, f) : read_chars(L, f, l);
 436             } else {
 437                 const char *p = lua_tostring(L, n);
 438                 luaL_argcheck(L, p && p[0] == '*', n, "invalid option");
 439                 switch (p[1]) {
 440                     case 'n':  /* number */
 441                         success = read_number(L, f);
 442                         break;
 443                     case 'l':  /* line */
 444                         success = read_line(L, f, 1);
 445                         break;
 446                     case 'L':  /* line with end-of-line */
 447                         success = read_line(L, f, 0);
 448                         break;
 449                     case 'a':  /* file */
 450                         read_all(L, f);  /* read entire file */
 451                         success = 1; /* always success */
 452                         break;
 453                     default:
 454                         return luaL_argerror(L, n, "invalid format");
 455                 }
 456             }
 457         }
 458     }
 459     if (ferror(f))
 460         return luaL_fileresult(L, 0, NULL);
 461     if (!success) {
 462         lua_pop(L, 1);  /* remove last result */
 463         lua_pushnil(L);  /* push nil instead */
 464     }
 465     return n - first;
 466 }
 467
 468
 469 static int io_read(lua_State *L) {
 470     return g_read(L, getiofile(L, IO_INPUT), 1);
 471 }
 472
 473
 474 static int f_read(lua_State *L) {
 475     return g_read(L, tofile(L), 2);
 476 }
 477
 478
 479 static int io_readline(lua_State *L) {
 480     LStream *p = (LStream *)lua_touserdata(L, lua_upvalueindex(1));
 481     int i;
 482     int n = (int)lua_tointeger(L, lua_upvalueindex(2));
 483     if (isclosed(p))  /* file is already closed? */
 484         return luaL_error(L, "file is already closed");
 485     lua_settop(L, 1);
 486     for (i = 1; i <= n; i++)  /* push arguments to 'g_read' */
 487         lua_pushvalue(L, lua_upvalueindex(3 + i));
 488     n = g_read(L, p->f, 2);  /* 'n' is number of results */
 489     lua_assert(n > 0);  /* should return at least a nil */
 490     if (!lua_isnil(L, -n))  /* read at least one value? */
 491         return n;  /* return them */
 492     else {  /* first result is nil: EOF or error */
 493         if (n > 1) {  /* is there error information? */
 494             /* 2nd result is error message */
 495             return luaL_error(L, "%s", lua_tostring(L, -n + 1));
 496         }
 497         if (lua_toboolean(L, lua_upvalueindex(3))) {  /* generator created file? */
 498             lua_settop(L, 0);
 499             lua_pushvalue(L, lua_upvalueindex(1));
 500             aux_close(L);  /* close it */
 501         }
 502         return 0;
 503     }
 504 }
 505
 506 /* }====================================================== */
 507
 508
 509 static int g_write(lua_State *L, FILE *f, int arg) {
 510     int nargs = lua_gettop(L) - arg;
 511     int status = 1;
 512     for (; nargs--; arg++) {
 513         if (lua_type(L, arg) == LUA_TNUMBER) {
 514             /* optimization: could be done exactly as for strings */
 515             status = status &&
 516                      fprintf(f, LUA_NUMBER_FMT, lua_tonumber(L, arg)) > 0;
 517         } else {
 518             size_t l;
 519             const char *s = luaL_checklstring(L, arg, &l);
 520             status = status && (fwrite(s, sizeof(char), l, f) == l);
 521         }
 522     }
 523     if (status) return 1;  /* file handle already on stack top */
 524     else return luaL_fileresult(L, status, NULL);
 525 }
 526
 527
 528 static int io_write(lua_State *L) {
 529     return g_write(L, getiofile(L, IO_OUTPUT), 1);
 530 }
 531
 532
 533 static int f_write(lua_State *L) {
 534     FILE *f = tofile(L);
 535     lua_pushvalue(L, 1);  /* push file at the stack top (to be returned) */
 536     return g_write(L, f, 2);
 537 }
 538
 539
 540 static int f_seek(lua_State *L) {
 541     static const int mode[] = {SEEK_SET, SEEK_CUR, SEEK_END};
 542     static const char *const modenames[] = {"set", "cur", "end", NULL};
 543     FILE *f = tofile(L);
 544     int op = luaL_checkoption(L, 2, "cur", modenames);
 545     lua_Number p3 = luaL_optnumber(L, 3, 0);
 546     l_seeknum offset = (l_seeknum)p3;
 547     luaL_argcheck(L, (lua_Number)offset == p3, 3,
 548                   "not an integer in proper range");
 549     op = l_fseek(f, offset, mode[op]);
 550     if (op)
 551         return luaL_fileresult(L, 0, NULL);  /* error */
 552     else {
 553         lua_pushnumber(L, (lua_Number)l_ftell(f));
 554         return 1;
 555     }
 556 }
 557
 558
 559 static int f_setvbuf(lua_State *L) {
 560     static const int mode[] = {_IONBF, _IOFBF, _IOLBF};
 561     static const char *const modenames[] = {"no", "full", "line", NULL};
 562     FILE *f = tofile(L);
 563     int op = luaL_checkoption(L, 2, NULL, modenames);
 564     lua_Integer sz = luaL_optinteger(L, 3, LUAL_BUFFERSIZE);
 565     int res = setvbuf(f, NULL, mode[op], sz);
 566     return luaL_fileresult(L, res == 0, NULL);
 567 }
 568
 569
 570
 571 static int io_flush(lua_State *L) {
 572     return luaL_fileresult(L, fflush(getiofile(L, IO_OUTPUT)) == 0, NULL);
 573 }
 574
 575
 576 static int f_flush(lua_State *L) {
 577     return luaL_fileresult(L, fflush(tofile(L)) == 0, NULL);
 578 }
 579
 580
 581 /*
 582 ** functions for 'io' library
 583 */
 584 static const luaL_Reg iolib[] = {
 585     {"close", io_close},
 586     {"flush", io_flush},
 587     {"input", io_input},
 588     {"lines", io_lines},
 589     {"open", io_open},
 590     {"output", io_output},
 591     {"popen", io_popen},
 592     {"read", io_read},
 593     {"tmpfile", io_tmpfile},
 594     {"type", io_type},
 595     {"write", io_write},
 596     {NULL, NULL}
 597 };
 598
 599
 600 /*
 601 ** methods for file handles
 602 */
 603 static const luaL_Reg flib[] = {
 604     {"close", io_close},
 605     {"flush", f_flush},
 606     {"lines", f_lines},
 607     {"read", f_read},
 608     {"seek", f_seek},
 609     {"setvbuf", f_setvbuf},
 610     {"write", f_write},
 611     {"__gc", f_gc},
 612     {"__tostring", f_tostring},
 613     {NULL, NULL}
 614 };
 615
 616
 617 static void createmeta(lua_State *L) {
 618     luaL_newmetatable(L, LUA_FILEHANDLE);  /* create metatable for file handles */
 619     lua_pushvalue(L, -1);  /* push metatable */
 620     lua_setfield(L, -2, "__index");  /* metatable.__index = metatable */
 621     luaL_setfuncs(L, flib, 0);  /* add file methods to new metatable */
 622     lua_pop(L, 1);  /* pop new metatable */
 623 }
 624
 625
 626 /*
 627 ** function to (not) close the standard files stdin, stdout, and stderr
 628 */
 629 static int io_noclose(lua_State *L) {
 630     LStream *p = tolstream(L);
 631     p->closef = &io_noclose;  /* keep file opened */
 632     lua_pushnil(L);
 633     lua_pushliteral(L, "cannot close standard file");
 634     return 2;
 635 }
 636
 637
 638 static void createstdfile(lua_State *L, FILE *f, const char *k,
 639                           const char *fname) {
 640     LStream *p = newprefile(L);
 641     p->f = f;
 642     p->closef = &io_noclose;
 643     if (k != NULL) {
 644         lua_pushvalue(L, -1);
 645         lua_setfield(L, LUA_REGISTRYINDEX, k);  /* add file to registry */
 646     }
 647     lua_setfield(L, -2, fname);  /* add file to module */
 648 }
 649
 650
 651 LUAMOD_API int luaopen_io(lua_State *L) {
 652     luaL_newlib(L, iolib);  /* new module */
 653     createmeta(L);
 654     /* create (and set) default files */
 655     createstdfile(L, stdin, IO_INPUT, "stdin");
 656     createstdfile(L, stdout, IO_OUTPUT, "stdout");
 657     createstdfile(L, stderr, NULL, "stderr");
 658     return 1;
 659 }
 660