wgenops.c 16 KB

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  1. /* Copyright (C) 1993-2019 Free Software Foundation, Inc.
  2. This file is part of the GNU C Library.
  3. Written by Ulrich Drepper <drepper@cygnus.com>.
  4. Based on the single byte version by Per Bothner <bothner@cygnus.com>.
  5. The GNU C Library is free software; you can redistribute it and/or
  6. modify it under the terms of the GNU Lesser General Public
  7. License as published by the Free Software Foundation; either
  8. version 2.1 of the License, or (at your option) any later version.
  9. The GNU C Library is distributed in the hope that it will be useful,
  10. but WITHOUT ANY WARRANTY; without even the implied warranty of
  11. MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  12. Lesser General Public License for more details.
  13. You should have received a copy of the GNU Lesser General Public
  14. License along with the GNU C Library; if not, see
  15. <http://www.gnu.org/licenses/>.
  16. As a special exception, if you link the code in this file with
  17. files compiled with a GNU compiler to produce an executable,
  18. that does not cause the resulting executable to be covered by
  19. the GNU Lesser General Public License. This exception does not
  20. however invalidate any other reasons why the executable file
  21. might be covered by the GNU Lesser General Public License.
  22. This exception applies to code released by its copyright holders
  23. in files containing the exception. */
  24. /* Generic or default I/O operations. */
  25. #include "libioP.h"
  26. #include <stdlib.h>
  27. #include <string.h>
  28. #include <wchar.h>
  29. static int save_for_wbackup (FILE *fp, wchar_t *end_p) __THROW;
  30. /* Return minimum _pos markers
  31. Assumes the current get area is the main get area. */
  32. ssize_t
  33. _IO_least_wmarker (FILE *fp, wchar_t *end_p)
  34. {
  35. ssize_t least_so_far = end_p - fp->_wide_data->_IO_read_base;
  36. struct _IO_marker *mark;
  37. for (mark = fp->_markers; mark != NULL; mark = mark->_next)
  38. if (mark->_pos < least_so_far)
  39. least_so_far = mark->_pos;
  40. return least_so_far;
  41. }
  42. libc_hidden_def (_IO_least_wmarker)
  43. /* Switch current get area from backup buffer to (start of) main get area. */
  44. void
  45. _IO_switch_to_main_wget_area (FILE *fp)
  46. {
  47. wchar_t *tmp;
  48. fp->_flags &= ~_IO_IN_BACKUP;
  49. /* Swap _IO_read_end and _IO_save_end. */
  50. tmp = fp->_wide_data->_IO_read_end;
  51. fp->_wide_data->_IO_read_end = fp->_wide_data->_IO_save_end;
  52. fp->_wide_data->_IO_save_end= tmp;
  53. /* Swap _IO_read_base and _IO_save_base. */
  54. tmp = fp->_wide_data->_IO_read_base;
  55. fp->_wide_data->_IO_read_base = fp->_wide_data->_IO_save_base;
  56. fp->_wide_data->_IO_save_base = tmp;
  57. /* Set _IO_read_ptr. */
  58. fp->_wide_data->_IO_read_ptr = fp->_wide_data->_IO_read_base;
  59. }
  60. libc_hidden_def (_IO_switch_to_main_wget_area)
  61. /* Switch current get area from main get area to (end of) backup area. */
  62. void
  63. _IO_switch_to_wbackup_area (FILE *fp)
  64. {
  65. wchar_t *tmp;
  66. fp->_flags |= _IO_IN_BACKUP;
  67. /* Swap _IO_read_end and _IO_save_end. */
  68. tmp = fp->_wide_data->_IO_read_end;
  69. fp->_wide_data->_IO_read_end = fp->_wide_data->_IO_save_end;
  70. fp->_wide_data->_IO_save_end = tmp;
  71. /* Swap _IO_read_base and _IO_save_base. */
  72. tmp = fp->_wide_data->_IO_read_base;
  73. fp->_wide_data->_IO_read_base = fp->_wide_data->_IO_save_base;
  74. fp->_wide_data->_IO_save_base = tmp;
  75. /* Set _IO_read_ptr. */
  76. fp->_wide_data->_IO_read_ptr = fp->_wide_data->_IO_read_end;
  77. }
  78. libc_hidden_def (_IO_switch_to_wbackup_area)
  79. void
  80. _IO_wsetb (FILE *f, wchar_t *b, wchar_t *eb, int a)
  81. {
  82. if (f->_wide_data->_IO_buf_base && !(f->_flags2 & _IO_FLAGS2_USER_WBUF))
  83. free (f->_wide_data->_IO_buf_base);
  84. f->_wide_data->_IO_buf_base = b;
  85. f->_wide_data->_IO_buf_end = eb;
  86. if (a)
  87. f->_flags2 &= ~_IO_FLAGS2_USER_WBUF;
  88. else
  89. f->_flags2 |= _IO_FLAGS2_USER_WBUF;
  90. }
  91. libc_hidden_def (_IO_wsetb)
  92. wint_t
  93. _IO_wdefault_pbackfail (FILE *fp, wint_t c)
  94. {
  95. if (fp->_wide_data->_IO_read_ptr > fp->_wide_data->_IO_read_base
  96. && !_IO_in_backup (fp)
  97. && (wint_t) fp->_IO_read_ptr[-1] == c)
  98. --fp->_IO_read_ptr;
  99. else
  100. {
  101. /* Need to handle a filebuf in write mode (switch to read mode). FIXME!*/
  102. if (!_IO_in_backup (fp))
  103. {
  104. /* We need to keep the invariant that the main get area
  105. logically follows the backup area. */
  106. if (fp->_wide_data->_IO_read_ptr > fp->_wide_data->_IO_read_base
  107. && _IO_have_wbackup (fp))
  108. {
  109. if (save_for_wbackup (fp, fp->_wide_data->_IO_read_ptr))
  110. return WEOF;
  111. }
  112. else if (!_IO_have_wbackup (fp))
  113. {
  114. /* No backup buffer: allocate one. */
  115. /* Use nshort buffer, if unused? (probably not) FIXME */
  116. int backup_size = 128;
  117. wchar_t *bbuf = (wchar_t *) malloc (backup_size
  118. * sizeof (wchar_t));
  119. if (bbuf == NULL)
  120. return WEOF;
  121. fp->_wide_data->_IO_save_base = bbuf;
  122. fp->_wide_data->_IO_save_end = (fp->_wide_data->_IO_save_base
  123. + backup_size);
  124. fp->_wide_data->_IO_backup_base = fp->_wide_data->_IO_save_end;
  125. }
  126. fp->_wide_data->_IO_read_base = fp->_wide_data->_IO_read_ptr;
  127. _IO_switch_to_wbackup_area (fp);
  128. }
  129. else if (fp->_wide_data->_IO_read_ptr <= fp->_wide_data->_IO_read_base)
  130. {
  131. /* Increase size of existing backup buffer. */
  132. size_t new_size;
  133. size_t old_size = (fp->_wide_data->_IO_read_end
  134. - fp->_wide_data->_IO_read_base);
  135. wchar_t *new_buf;
  136. new_size = 2 * old_size;
  137. new_buf = (wchar_t *) malloc (new_size * sizeof (wchar_t));
  138. if (new_buf == NULL)
  139. return WEOF;
  140. __wmemcpy (new_buf + (new_size - old_size),
  141. fp->_wide_data->_IO_read_base, old_size);
  142. free (fp->_wide_data->_IO_read_base);
  143. _IO_wsetg (fp, new_buf, new_buf + (new_size - old_size),
  144. new_buf + new_size);
  145. fp->_wide_data->_IO_backup_base = fp->_wide_data->_IO_read_ptr;
  146. }
  147. *--fp->_wide_data->_IO_read_ptr = c;
  148. }
  149. return c;
  150. }
  151. libc_hidden_def (_IO_wdefault_pbackfail)
  152. void
  153. _IO_wdefault_finish (FILE *fp, int dummy)
  154. {
  155. struct _IO_marker *mark;
  156. if (fp->_wide_data->_IO_buf_base && !(fp->_flags2 & _IO_FLAGS2_USER_WBUF))
  157. {
  158. free (fp->_wide_data->_IO_buf_base);
  159. fp->_wide_data->_IO_buf_base = fp->_wide_data->_IO_buf_end = NULL;
  160. }
  161. for (mark = fp->_markers; mark != NULL; mark = mark->_next)
  162. mark->_sbuf = NULL;
  163. if (fp->_IO_save_base)
  164. {
  165. free (fp->_wide_data->_IO_save_base);
  166. fp->_IO_save_base = NULL;
  167. }
  168. #ifdef _IO_MTSAFE_IO
  169. if (fp->_lock != NULL)
  170. _IO_lock_fini (*fp->_lock);
  171. #endif
  172. _IO_un_link ((struct _IO_FILE_plus *) fp);
  173. }
  174. libc_hidden_def (_IO_wdefault_finish)
  175. wint_t
  176. _IO_wdefault_uflow (FILE *fp)
  177. {
  178. wint_t wch;
  179. wch = _IO_UNDERFLOW (fp);
  180. if (wch == WEOF)
  181. return WEOF;
  182. return *fp->_wide_data->_IO_read_ptr++;
  183. }
  184. libc_hidden_def (_IO_wdefault_uflow)
  185. wint_t
  186. __woverflow (FILE *f, wint_t wch)
  187. {
  188. if (f->_mode == 0)
  189. _IO_fwide (f, 1);
  190. return _IO_OVERFLOW (f, wch);
  191. }
  192. libc_hidden_def (__woverflow)
  193. wint_t
  194. __wuflow (FILE *fp)
  195. {
  196. if (fp->_mode < 0 || (fp->_mode == 0 && _IO_fwide (fp, 1) != 1))
  197. return WEOF;
  198. if (fp->_mode == 0)
  199. _IO_fwide (fp, 1);
  200. if (_IO_in_put_mode (fp))
  201. if (_IO_switch_to_wget_mode (fp) == EOF)
  202. return WEOF;
  203. if (fp->_wide_data->_IO_read_ptr < fp->_wide_data->_IO_read_end)
  204. return *fp->_wide_data->_IO_read_ptr++;
  205. if (_IO_in_backup (fp))
  206. {
  207. _IO_switch_to_main_wget_area (fp);
  208. if (fp->_wide_data->_IO_read_ptr < fp->_wide_data->_IO_read_end)
  209. return *fp->_wide_data->_IO_read_ptr++;
  210. }
  211. if (_IO_have_markers (fp))
  212. {
  213. if (save_for_wbackup (fp, fp->_wide_data->_IO_read_end))
  214. return WEOF;
  215. }
  216. else if (_IO_have_wbackup (fp))
  217. _IO_free_wbackup_area (fp);
  218. return _IO_UFLOW (fp);
  219. }
  220. libc_hidden_def (__wuflow)
  221. wint_t
  222. __wunderflow (FILE *fp)
  223. {
  224. if (fp->_mode < 0 || (fp->_mode == 0 && _IO_fwide (fp, 1) != 1))
  225. return WEOF;
  226. if (fp->_mode == 0)
  227. _IO_fwide (fp, 1);
  228. if (_IO_in_put_mode (fp))
  229. if (_IO_switch_to_wget_mode (fp) == EOF)
  230. return WEOF;
  231. if (fp->_wide_data->_IO_read_ptr < fp->_wide_data->_IO_read_end)
  232. return *fp->_wide_data->_IO_read_ptr;
  233. if (_IO_in_backup (fp))
  234. {
  235. _IO_switch_to_main_wget_area (fp);
  236. if (fp->_wide_data->_IO_read_ptr < fp->_wide_data->_IO_read_end)
  237. return *fp->_wide_data->_IO_read_ptr;
  238. }
  239. if (_IO_have_markers (fp))
  240. {
  241. if (save_for_wbackup (fp, fp->_wide_data->_IO_read_end))
  242. return WEOF;
  243. }
  244. else if (_IO_have_backup (fp))
  245. _IO_free_wbackup_area (fp);
  246. return _IO_UNDERFLOW (fp);
  247. }
  248. libc_hidden_def (__wunderflow)
  249. size_t
  250. _IO_wdefault_xsputn (FILE *f, const void *data, size_t n)
  251. {
  252. const wchar_t *s = (const wchar_t *) data;
  253. size_t more = n;
  254. if (more <= 0)
  255. return 0;
  256. for (;;)
  257. {
  258. /* Space available. */
  259. ssize_t count = (f->_wide_data->_IO_write_end
  260. - f->_wide_data->_IO_write_ptr);
  261. if (count > 0)
  262. {
  263. if ((size_t) count > more)
  264. count = more;
  265. if (count > 20)
  266. {
  267. f->_wide_data->_IO_write_ptr =
  268. __wmempcpy (f->_wide_data->_IO_write_ptr, s, count);
  269. s += count;
  270. }
  271. else if (count <= 0)
  272. count = 0;
  273. else
  274. {
  275. wchar_t *p = f->_wide_data->_IO_write_ptr;
  276. ssize_t i;
  277. for (i = count; --i >= 0; )
  278. *p++ = *s++;
  279. f->_wide_data->_IO_write_ptr = p;
  280. }
  281. more -= count;
  282. }
  283. if (more == 0 || __woverflow (f, *s++) == WEOF)
  284. break;
  285. more--;
  286. }
  287. return n - more;
  288. }
  289. libc_hidden_def (_IO_wdefault_xsputn)
  290. size_t
  291. _IO_wdefault_xsgetn (FILE *fp, void *data, size_t n)
  292. {
  293. size_t more = n;
  294. wchar_t *s = (wchar_t*) data;
  295. for (;;)
  296. {
  297. /* Data available. */
  298. ssize_t count = (fp->_wide_data->_IO_read_end
  299. - fp->_wide_data->_IO_read_ptr);
  300. if (count > 0)
  301. {
  302. if ((size_t) count > more)
  303. count = more;
  304. if (count > 20)
  305. {
  306. s = __wmempcpy (s, fp->_wide_data->_IO_read_ptr, count);
  307. fp->_wide_data->_IO_read_ptr += count;
  308. }
  309. else if (count <= 0)
  310. count = 0;
  311. else
  312. {
  313. wchar_t *p = fp->_wide_data->_IO_read_ptr;
  314. int i = (int) count;
  315. while (--i >= 0)
  316. *s++ = *p++;
  317. fp->_wide_data->_IO_read_ptr = p;
  318. }
  319. more -= count;
  320. }
  321. if (more == 0 || __wunderflow (fp) == WEOF)
  322. break;
  323. }
  324. return n - more;
  325. }
  326. libc_hidden_def (_IO_wdefault_xsgetn)
  327. void
  328. _IO_wdoallocbuf (FILE *fp)
  329. {
  330. if (fp->_wide_data->_IO_buf_base)
  331. return;
  332. if (!(fp->_flags & _IO_UNBUFFERED))
  333. if ((wint_t)_IO_WDOALLOCATE (fp) != WEOF)
  334. return;
  335. _IO_wsetb (fp, fp->_wide_data->_shortbuf,
  336. fp->_wide_data->_shortbuf + 1, 0);
  337. }
  338. libc_hidden_def (_IO_wdoallocbuf)
  339. int
  340. _IO_wdefault_doallocate (FILE *fp)
  341. {
  342. wchar_t *buf;
  343. buf = malloc (BUFSIZ);
  344. if (__glibc_unlikely (buf == NULL))
  345. return EOF;
  346. _IO_wsetb (fp, buf, buf + BUFSIZ, 1);
  347. return 1;
  348. }
  349. libc_hidden_def (_IO_wdefault_doallocate)
  350. int
  351. _IO_switch_to_wget_mode (FILE *fp)
  352. {
  353. if (fp->_wide_data->_IO_write_ptr > fp->_wide_data->_IO_write_base)
  354. if ((wint_t)_IO_WOVERFLOW (fp, WEOF) == WEOF)
  355. return EOF;
  356. if (_IO_in_backup (fp))
  357. fp->_wide_data->_IO_read_base = fp->_wide_data->_IO_backup_base;
  358. else
  359. {
  360. fp->_wide_data->_IO_read_base = fp->_wide_data->_IO_buf_base;
  361. if (fp->_wide_data->_IO_write_ptr > fp->_wide_data->_IO_read_end)
  362. fp->_wide_data->_IO_read_end = fp->_wide_data->_IO_write_ptr;
  363. }
  364. fp->_wide_data->_IO_read_ptr = fp->_wide_data->_IO_write_ptr;
  365. fp->_wide_data->_IO_write_base = fp->_wide_data->_IO_write_ptr
  366. = fp->_wide_data->_IO_write_end = fp->_wide_data->_IO_read_ptr;
  367. fp->_flags &= ~_IO_CURRENTLY_PUTTING;
  368. return 0;
  369. }
  370. libc_hidden_def (_IO_switch_to_wget_mode)
  371. void
  372. _IO_free_wbackup_area (FILE *fp)
  373. {
  374. if (_IO_in_backup (fp))
  375. _IO_switch_to_main_wget_area (fp); /* Just in case. */
  376. free (fp->_wide_data->_IO_save_base);
  377. fp->_wide_data->_IO_save_base = NULL;
  378. fp->_wide_data->_IO_save_end = NULL;
  379. fp->_wide_data->_IO_backup_base = NULL;
  380. }
  381. libc_hidden_def (_IO_free_wbackup_area)
  382. static int
  383. save_for_wbackup (FILE *fp, wchar_t *end_p)
  384. {
  385. /* Append [_IO_read_base..end_p] to backup area. */
  386. ssize_t least_mark = _IO_least_wmarker (fp, end_p);
  387. /* needed_size is how much space we need in the backup area. */
  388. size_t needed_size = ((end_p - fp->_wide_data->_IO_read_base)
  389. - least_mark);
  390. /* FIXME: Dubious arithmetic if pointers are NULL */
  391. size_t current_Bsize = (fp->_wide_data->_IO_save_end
  392. - fp->_wide_data->_IO_save_base);
  393. size_t avail; /* Extra space available for future expansion. */
  394. ssize_t delta;
  395. struct _IO_marker *mark;
  396. if (needed_size > current_Bsize)
  397. {
  398. wchar_t *new_buffer;
  399. avail = 100;
  400. new_buffer = (wchar_t *) malloc ((avail + needed_size)
  401. * sizeof (wchar_t));
  402. if (new_buffer == NULL)
  403. return EOF; /* FIXME */
  404. if (least_mark < 0)
  405. {
  406. __wmempcpy (__wmempcpy (new_buffer + avail,
  407. fp->_wide_data->_IO_save_end + least_mark,
  408. -least_mark),
  409. fp->_wide_data->_IO_read_base,
  410. end_p - fp->_wide_data->_IO_read_base);
  411. }
  412. else
  413. {
  414. __wmemcpy (new_buffer + avail,
  415. fp->_wide_data->_IO_read_base + least_mark,
  416. needed_size);
  417. }
  418. free (fp->_wide_data->_IO_save_base);
  419. fp->_wide_data->_IO_save_base = new_buffer;
  420. fp->_wide_data->_IO_save_end = new_buffer + avail + needed_size;
  421. }
  422. else
  423. {
  424. avail = current_Bsize - needed_size;
  425. if (least_mark < 0)
  426. {
  427. __wmemmove (fp->_wide_data->_IO_save_base + avail,
  428. fp->_wide_data->_IO_save_end + least_mark,
  429. -least_mark);
  430. __wmemcpy (fp->_wide_data->_IO_save_base + avail - least_mark,
  431. fp->_wide_data->_IO_read_base,
  432. end_p - fp->_wide_data->_IO_read_base);
  433. }
  434. else if (needed_size > 0)
  435. __wmemcpy (fp->_wide_data->_IO_save_base + avail,
  436. fp->_wide_data->_IO_read_base + least_mark,
  437. needed_size);
  438. }
  439. fp->_wide_data->_IO_backup_base = fp->_wide_data->_IO_save_base + avail;
  440. /* Adjust all the streammarkers. */
  441. delta = end_p - fp->_wide_data->_IO_read_base;
  442. for (mark = fp->_markers; mark != NULL; mark = mark->_next)
  443. mark->_pos -= delta;
  444. return 0;
  445. }
  446. wint_t
  447. _IO_sputbackwc (FILE *fp, wint_t c)
  448. {
  449. wint_t result;
  450. if (fp->_wide_data->_IO_read_ptr > fp->_wide_data->_IO_read_base
  451. && (wchar_t)fp->_wide_data->_IO_read_ptr[-1] == (wchar_t) c)
  452. {
  453. fp->_wide_data->_IO_read_ptr--;
  454. result = c;
  455. }
  456. else
  457. result = _IO_PBACKFAIL (fp, c);
  458. if (result != WEOF)
  459. fp->_flags &= ~_IO_EOF_SEEN;
  460. return result;
  461. }
  462. libc_hidden_def (_IO_sputbackwc)
  463. wint_t
  464. _IO_sungetwc (FILE *fp)
  465. {
  466. wint_t result;
  467. if (fp->_wide_data->_IO_read_ptr > fp->_wide_data->_IO_read_base)
  468. {
  469. fp->_wide_data->_IO_read_ptr--;
  470. result = *fp->_wide_data->_IO_read_ptr;
  471. }
  472. else
  473. result = _IO_PBACKFAIL (fp, EOF);
  474. if (result != WEOF)
  475. fp->_flags &= ~_IO_EOF_SEEN;
  476. return result;
  477. }
  478. unsigned
  479. _IO_adjust_wcolumn (unsigned start, const wchar_t *line, int count)
  480. {
  481. const wchar_t *ptr = line + count;
  482. while (ptr > line)
  483. if (*--ptr == L'\n')
  484. return line + count - ptr - 1;
  485. return start + count;
  486. }
  487. void
  488. _IO_init_wmarker (struct _IO_marker *marker, FILE *fp)
  489. {
  490. marker->_sbuf = fp;
  491. if (_IO_in_put_mode (fp))
  492. _IO_switch_to_wget_mode (fp);
  493. if (_IO_in_backup (fp))
  494. marker->_pos = fp->_wide_data->_IO_read_ptr - fp->_wide_data->_IO_read_end;
  495. else
  496. marker->_pos = (fp->_wide_data->_IO_read_ptr
  497. - fp->_wide_data->_IO_read_base);
  498. /* Should perhaps sort the chain? */
  499. marker->_next = fp->_markers;
  500. fp->_markers = marker;
  501. }
  502. #define BAD_DELTA EOF
  503. /* Return difference between MARK and current position of MARK's stream. */
  504. int
  505. _IO_wmarker_delta (struct _IO_marker *mark)
  506. {
  507. int cur_pos;
  508. if (mark->_sbuf == NULL)
  509. return BAD_DELTA;
  510. if (_IO_in_backup (mark->_sbuf))
  511. cur_pos = (mark->_sbuf->_wide_data->_IO_read_ptr
  512. - mark->_sbuf->_wide_data->_IO_read_end);
  513. else
  514. cur_pos = (mark->_sbuf->_wide_data->_IO_read_ptr
  515. - mark->_sbuf->_wide_data->_IO_read_base);
  516. return mark->_pos - cur_pos;
  517. }
  518. int
  519. _IO_seekwmark (FILE *fp, struct _IO_marker *mark, int delta)
  520. {
  521. if (mark->_sbuf != fp)
  522. return EOF;
  523. if (mark->_pos >= 0)
  524. {
  525. if (_IO_in_backup (fp))
  526. _IO_switch_to_main_wget_area (fp);
  527. fp->_wide_data->_IO_read_ptr = (fp->_wide_data->_IO_read_base
  528. + mark->_pos);
  529. }
  530. else
  531. {
  532. if (!_IO_in_backup (fp))
  533. _IO_switch_to_wbackup_area (fp);
  534. fp->_wide_data->_IO_read_ptr = fp->_wide_data->_IO_read_end + mark->_pos;
  535. }
  536. return 0;
  537. }
  538. void
  539. _IO_unsave_wmarkers (FILE *fp)
  540. {
  541. struct _IO_marker *mark = fp->_markers;
  542. if (mark)
  543. {
  544. fp->_markers = 0;
  545. }
  546. if (_IO_have_backup (fp))
  547. _IO_free_wbackup_area (fp);
  548. }