]>
Commit | Line | Data |
---|---|---|
ba8b5c17 | 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 |