Mercurial > vba-clojure

comparison src/lua/liolib.c @ 11:27763b933818

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
raise lua sources up one level
author Robert McIntyre <rlm@mit.edu>
date Sat, 03 Mar 2012 11:07:39 -0600
parents src/lua/src/liolib.c@f9f4f1b99eed
children
comparison
equal deleted inserted replaced
10:48b74a4e4692 11:27763b933818
1 /*
2 ** $Id: liolib.c,v 2.73.1.3 2008/01/18 17:47:43 roberto Exp $
3 ** Standard I/O (and system) library
4 ** See Copyright Notice in lua.h
5 */
6
7
8 #include <errno.h>
9 #include <stdio.h>
10 #include <stdlib.h>
11 #include <string.h>
12
13 #define liolib_c
14 #define LUA_LIB
15
16 #include "lua.h"
17
18 #include "lauxlib.h"
19 #include "lualib.h"
20
21
22
23 #define IO_INPUT 1
24 #define IO_OUTPUT 2
25
26
27 static const char *const fnames[] = {"input", "output"};
28
29
30 static int pushresult (lua_State *L, int i, const char *filename) {
31 int en = errno; /* calls to Lua API may change this value */
32 if (i) {
33 lua_pushboolean(L, 1);
34 return 1;
35 }
36 else {
37 lua_pushnil(L);
38 if (filename)
39 lua_pushfstring(L, "%s: %s", filename, strerror(en));
40 else
41 lua_pushfstring(L, "%s", strerror(en));
42 lua_pushinteger(L, en);
43 return 3;
44 }
45 }
46
47
48 static void fileerror (lua_State *L, int arg, const char *filename) {
49 lua_pushfstring(L, "%s: %s", filename, strerror(errno));
50 luaL_argerror(L, arg, lua_tostring(L, -1));
51 }
52
53
54 #define tofilep(L) ((FILE **)luaL_checkudata(L, 1, LUA_FILEHANDLE))
55
56
57 static int io_type (lua_State *L) {
58 void *ud;
59 luaL_checkany(L, 1);
60 ud = lua_touserdata(L, 1);
61 lua_getfield(L, LUA_REGISTRYINDEX, LUA_FILEHANDLE);
62 if (ud == NULL || !lua_getmetatable(L, 1) || !lua_rawequal(L, -2, -1))
63 lua_pushnil(L); /* not a file */
64 else if (*((FILE **)ud) == NULL)
65 lua_pushliteral(L, "closed file");
66 else
67 lua_pushliteral(L, "file");
68 return 1;
69 }
70
71
72 static FILE *tofile (lua_State *L) {
73 FILE **f = tofilep(L);
74 if (*f == NULL)
75 luaL_error(L, "attempt to use a closed file");
76 return *f;
77 }
78
79
80
81 /*
82 ** When creating file handles, always creates a `closed' file handle
83 ** before opening the actual file; so, if there is a memory error, the
84 ** file is not left opened.
85 */
86 static FILE **newfile (lua_State *L) {
87 FILE **pf = (FILE **)lua_newuserdata(L, sizeof(FILE *));
88 *pf = NULL; /* file handle is currently `closed' */
89 luaL_getmetatable(L, LUA_FILEHANDLE);
90 lua_setmetatable(L, -2);
91 return pf;
92 }
93
94
95 /*
96 ** function to (not) close the standard files stdin, stdout, and stderr
97 */
98 static int io_noclose (lua_State *L) {
99 lua_pushnil(L);
100 lua_pushliteral(L, "cannot close standard file");
101 return 2;
102 }
103
104
105 /*
106 ** function to close 'popen' files
107 */
108 static int io_pclose (lua_State *L) {
109 FILE **p = tofilep(L);
110 int ok = lua_pclose(L, *p);
111 *p = NULL;
112 return pushresult(L, ok, NULL);
113 }
114
115
116 /*
117 ** function to close regular files
118 */
119 static int io_fclose (lua_State *L) {
120 FILE **p = tofilep(L);
121 int ok = (fclose(*p) == 0);
122 *p = NULL;
123 return pushresult(L, ok, NULL);
124 }
125
126
127 static int aux_close (lua_State *L) {
128 lua_getfenv(L, 1);
129 lua_getfield(L, -1, "__close");
130 return (lua_tocfunction(L, -1))(L);
131 }
132
133
134 static int io_close (lua_State *L) {
135 if (lua_isnone(L, 1))
136 lua_rawgeti(L, LUA_ENVIRONINDEX, IO_OUTPUT);
137 tofile(L); /* make sure argument is a file */
138 return aux_close(L);
139 }
140
141
142 static int io_gc (lua_State *L) {
143 FILE *f = *tofilep(L);
144 /* ignore closed files */
145 if (f != NULL)
146 aux_close(L);
147 return 0;
148 }
149
150
151 static int io_tostring (lua_State *L) {
152 FILE *f = *tofilep(L);
153 if (f == NULL)
154 lua_pushliteral(L, "file (closed)");
155 else
156 lua_pushfstring(L, "file (%p)", f);
157 return 1;
158 }
159
160
161 static int io_open (lua_State *L) {
162 const char *filename = luaL_checkstring(L, 1);
163 const char *mode = luaL_optstring(L, 2, "r");
164 FILE **pf = newfile(L);
165 *pf = fopen(filename, mode);
166 return (*pf == NULL) ? pushresult(L, 0, filename) : 1;
167 }
168
169
170 /*
171 ** this function has a separated environment, which defines the
172 ** correct __close for 'popen' files
173 */
174 static int io_popen (lua_State *L) {
175 const char *filename = luaL_checkstring(L, 1);
176 const char *mode = luaL_optstring(L, 2, "r");
177 FILE **pf = newfile(L);
178 *pf = lua_popen(L, filename, mode);
179 return (*pf == NULL) ? pushresult(L, 0, filename) : 1;
180 }
181
182
183 static int io_tmpfile (lua_State *L) {
184 FILE **pf = newfile(L);
185 *pf = tmpfile();
186 return (*pf == NULL) ? pushresult(L, 0, NULL) : 1;
187 }
188
189
190 static FILE *getiofile (lua_State *L, int findex) {
191 FILE *f;
192 lua_rawgeti(L, LUA_ENVIRONINDEX, findex);
193 f = *(FILE **)lua_touserdata(L, -1);
194 if (f == NULL)
195 luaL_error(L, "standard %s file is closed", fnames[findex - 1]);
196 return f;
197 }
198
199
200 static int g_iofile (lua_State *L, int f, const char *mode) {
201 if (!lua_isnoneornil(L, 1)) {
202 const char *filename = lua_tostring(L, 1);
203 if (filename) {
204 FILE **pf = newfile(L);
205 *pf = fopen(filename, mode);
206 if (*pf == NULL)
207 fileerror(L, 1, filename);
208 }
209 else {
210 tofile(L); /* check that it's a valid file handle */
211 lua_pushvalue(L, 1);
212 }
213 lua_rawseti(L, LUA_ENVIRONINDEX, f);
214 }
215 /* return current value */
216 lua_rawgeti(L, LUA_ENVIRONINDEX, f);
217 return 1;
218 }
219
220
221 static int io_input (lua_State *L) {
222 return g_iofile(L, IO_INPUT, "r");
223 }
224
225
226 static int io_output (lua_State *L) {
227 return g_iofile(L, IO_OUTPUT, "w");
228 }
229
230
231 static int io_readline (lua_State *L);
232
233
234 static void aux_lines (lua_State *L, int idx, int toclose) {
235 lua_pushvalue(L, idx);
236 lua_pushboolean(L, toclose); /* close/not close file when finished */
237 lua_pushcclosure(L, io_readline, 2);
238 }
239
240
241 static int f_lines (lua_State *L) {
242 tofile(L); /* check that it's a valid file handle */
243 aux_lines(L, 1, 0);
244 return 1;
245 }
246
247
248 static int io_lines (lua_State *L) {
249 if (lua_isnoneornil(L, 1)) { /* no arguments? */
250 /* will iterate over default input */
251 lua_rawgeti(L, LUA_ENVIRONINDEX, IO_INPUT);
252 return f_lines(L);
253 }
254 else {
255 const char *filename = luaL_checkstring(L, 1);
256 FILE **pf = newfile(L);
257 *pf = fopen(filename, "r");
258 if (*pf == NULL)
259 fileerror(L, 1, filename);
260 aux_lines(L, lua_gettop(L), 1);
261 return 1;
262 }
263 }
264
265
266 /*
267 ** {======================================================
268 ** READ
269 ** =======================================================
270 */
271
272
273 static int read_number (lua_State *L, FILE *f) {
274 lua_Number d;
275 if (fscanf(f, LUA_NUMBER_SCAN, &d) == 1) {
276 lua_pushnumber(L, d);
277 return 1;
278 }
279 else return 0; /* read fails */
280 }
281
282
283 static int test_eof (lua_State *L, FILE *f) {
284 int c = getc(f);
285 ungetc(c, f);
286 lua_pushlstring(L, NULL, 0);
287 return (c != EOF);
288 }
289
290
291 static int read_line (lua_State *L, FILE *f) {
292 luaL_Buffer b;
293 luaL_buffinit(L, &b);
294 for (;;) {
295 size_t l;
296 char *p = luaL_prepbuffer(&b);
297 if (fgets(p, LUAL_BUFFERSIZE, f) == NULL) { /* eof? */
298 luaL_pushresult(&b); /* close buffer */
299 return (lua_objlen(L, -1) > 0); /* check whether read something */
300 }
301 l = strlen(p);
302 if (l == 0 || p[l-1] != '\n')
303 luaL_addsize(&b, l);
304 else {
305 luaL_addsize(&b, l - 1); /* do not include `eol' */
306 luaL_pushresult(&b); /* close buffer */
307 return 1; /* read at least an `eol' */
308 }
309 }
310 }
311
312
313 static int read_chars (lua_State *L, FILE *f, size_t n) {
314 size_t rlen; /* how much to read */
315 size_t nr; /* number of chars actually read */
316 luaL_Buffer b;
317 luaL_buffinit(L, &b);
318 rlen = LUAL_BUFFERSIZE; /* try to read that much each time */
319 do {
320 char *p = luaL_prepbuffer(&b);
321 if (rlen > n) rlen = n; /* cannot read more than asked */
322 nr = fread(p, sizeof(char), rlen, f);
323 luaL_addsize(&b, nr);
324 n -= nr; /* still have to read `n' chars */
325 } while (n > 0 && nr == rlen); /* until end of count or eof */
326 luaL_pushresult(&b); /* close buffer */
327 return (n == 0 || lua_objlen(L, -1) > 0);
328 }
329
330
331 static int g_read (lua_State *L, FILE *f, int first) {
332 int nargs = lua_gettop(L) - 1;
333 int success;
334 int n;
335 clearerr(f);
336 if (nargs == 0) { /* no arguments? */
337 success = read_line(L, f);
338 n = first+1; /* to return 1 result */
339 }
340 else { /* ensure stack space for all results and for auxlib's buffer */
341 luaL_checkstack(L, nargs+LUA_MINSTACK, "too many arguments");
342 success = 1;
343 for (n = first; nargs-- && success; n++) {
344 if (lua_type(L, n) == LUA_TNUMBER) {
345 size_t l = (size_t)lua_tointeger(L, n);
346 success = (l == 0) ? test_eof(L, f) : read_chars(L, f, l);
347 }
348 else {
349 const char *p = lua_tostring(L, n);
350 luaL_argcheck(L, p && p[0] == '*', n, "invalid option");
351 switch (p[1]) {
352 case 'n': /* number */
353 success = read_number(L, f);
354 break;
355 case 'l': /* line */
356 success = read_line(L, f);
357 break;
358 case 'a': /* file */
359 read_chars(L, f, ~((size_t)0)); /* read MAX_SIZE_T chars */
360 success = 1; /* always success */
361 break;
362 default:
363 return luaL_argerror(L, n, "invalid format");
364 }
365 }
366 }
367 }
368 if (ferror(f))
369 return pushresult(L, 0, NULL);
370 if (!success) {
371 lua_pop(L, 1); /* remove last result */
372 lua_pushnil(L); /* push nil instead */
373 }
374 return n - first;
375 }
376
377
378 static int io_read (lua_State *L) {
379 return g_read(L, getiofile(L, IO_INPUT), 1);
380 }
381
382
383 static int f_read (lua_State *L) {
384 return g_read(L, tofile(L), 2);
385 }
386
387
388 static int io_readline (lua_State *L) {
389 FILE *f = *(FILE **)lua_touserdata(L, lua_upvalueindex(1));
390 int sucess;
391 if (f == NULL) /* file is already closed? */
392 luaL_error(L, "file is already closed");
393 sucess = read_line(L, f);
394 if (ferror(f))
395 return luaL_error(L, "%s", strerror(errno));
396 if (sucess) return 1;
397 else { /* EOF */
398 if (lua_toboolean(L, lua_upvalueindex(2))) { /* generator created file? */
399 lua_settop(L, 0);
400 lua_pushvalue(L, lua_upvalueindex(1));
401 aux_close(L); /* close it */
402 }
403 return 0;
404 }
405 }
406
407 /* }====================================================== */
408
409
410 static int g_write (lua_State *L, FILE *f, int arg) {
411 int nargs = lua_gettop(L) - 1;
412 int status = 1;
413 for (; nargs--; arg++) {
414 if (lua_type(L, arg) == LUA_TNUMBER) {
415 /* optimization: could be done exactly as for strings */
416 status = status &&
417 fprintf(f, LUA_NUMBER_FMT, lua_tonumber(L, arg)) > 0;
418 }
419 else {
420 size_t l;
421 const char *s = luaL_checklstring(L, arg, &l);
422 status = status && (fwrite(s, sizeof(char), l, f) == l);
423 }
424 }
425 return pushresult(L, status, NULL);
426 }
427
428
429 static int io_write (lua_State *L) {
430 return g_write(L, getiofile(L, IO_OUTPUT), 1);
431 }
432
433
434 static int f_write (lua_State *L) {
435 return g_write(L, tofile(L), 2);
436 }
437
438
439 static int f_seek (lua_State *L) {
440 static const int mode[] = {SEEK_SET, SEEK_CUR, SEEK_END};
441 static const char *const modenames[] = {"set", "cur", "end", NULL};
442 FILE *f = tofile(L);
443 int op = luaL_checkoption(L, 2, "cur", modenames);
444 long offset = luaL_optlong(L, 3, 0);
445 op = fseek(f, offset, mode[op]);
446 if (op)
447 return pushresult(L, 0, NULL); /* error */
448 else {
449 lua_pushinteger(L, ftell(f));
450 return 1;
451 }
452 }
453
454
455 static int f_setvbuf (lua_State *L) {
456 static const int mode[] = {_IONBF, _IOFBF, _IOLBF};
457 static const char *const modenames[] = {"no", "full", "line", NULL};
458 FILE *f = tofile(L);
459 int op = luaL_checkoption(L, 2, NULL, modenames);
460 lua_Integer sz = luaL_optinteger(L, 3, LUAL_BUFFERSIZE);
461 int res = setvbuf(f, NULL, mode[op], sz);
462 return pushresult(L, res == 0, NULL);
463 }
464
465
466
467 static int io_flush (lua_State *L) {
468 return pushresult(L, fflush(getiofile(L, IO_OUTPUT)) == 0, NULL);
469 }
470
471
472 static int f_flush (lua_State *L) {
473 return pushresult(L, fflush(tofile(L)) == 0, NULL);
474 }
475
476
477 static const luaL_Reg iolib[] = {
478 {"close", io_close},
479 {"flush", io_flush},
480 {"input", io_input},
481 {"lines", io_lines},
482 {"open", io_open},
483 {"output", io_output},
484 {"popen", io_popen},
485 {"read", io_read},
486 {"tmpfile", io_tmpfile},
487 {"type", io_type},
488 {"write", io_write},
489 {NULL, NULL}
490 };
491
492
493 static const luaL_Reg flib[] = {
494 {"close", io_close},
495 {"flush", f_flush},
496 {"lines", f_lines},
497 {"read", f_read},
498 {"seek", f_seek},
499 {"setvbuf", f_setvbuf},
500 {"write", f_write},
501 {"__gc", io_gc},
502 {"__tostring", io_tostring},
503 {NULL, NULL}
504 };
505
506
507 static void createmeta (lua_State *L) {
508 luaL_newmetatable(L, LUA_FILEHANDLE); /* create metatable for file handles */
509 lua_pushvalue(L, -1); /* push metatable */
510 lua_setfield(L, -2, "__index"); /* metatable.__index = metatable */
511 luaL_register(L, NULL, flib); /* file methods */
512 }
513
514
515 static void createstdfile (lua_State *L, FILE *f, int k, const char *fname) {
516 *newfile(L) = f;
517 if (k > 0) {
518 lua_pushvalue(L, -1);
519 lua_rawseti(L, LUA_ENVIRONINDEX, k);
520 }
521 lua_pushvalue(L, -2); /* copy environment */
522 lua_setfenv(L, -2); /* set it */
523 lua_setfield(L, -3, fname);
524 }
525
526
527 static void newfenv (lua_State *L, lua_CFunction cls) {
528 lua_createtable(L, 0, 1);
529 lua_pushcfunction(L, cls);
530 lua_setfield(L, -2, "__close");
531 }
532
533
534 LUALIB_API int luaopen_io (lua_State *L) {
535 createmeta(L);
536 /* create (private) environment (with fields IO_INPUT, IO_OUTPUT, __close) */
537 newfenv(L, io_fclose);
538 lua_replace(L, LUA_ENVIRONINDEX);
539 /* open library */
540 luaL_register(L, LUA_IOLIBNAME, iolib);
541 /* create (and set) default files */
542 newfenv(L, io_noclose); /* close function for default files */
543 createstdfile(L, stdin, IO_INPUT, "stdin");
544 createstdfile(L, stdout, IO_OUTPUT, "stdout");
545 createstdfile(L, stderr, 0, "stderr");
546 lua_pop(L, 1); /* pop environment for default files */
547 lua_getfield(L, -1, "popen");
548 newfenv(L, io_pclose); /* create environment for 'popen' */
549 lua_setfenv(L, -2); /* set fenv for 'popen' */
550 lua_pop(L, 1); /* pop 'popen' */
551 return 1;
552 }
553