1/* Copyright (C) 1993-2020 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3 Written by Per Bothner <bothner@cygnus.com>.
4
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
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
14
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, see
17 <https://www.gnu.org/licenses/>.
18
19 As a special exception, if you link the code in this file with
20 files compiled with a GNU compiler to produce an executable,
21 that does not cause the resulting executable to be covered by
22 the GNU Lesser General Public License. This exception does not
23 however invalidate any other reasons why the executable file
24 might be covered by the GNU Lesser General Public License.
25 This exception applies to code released by its copyright holders
26 in files containing the exception. */
27
28
29#include "libioP.h"
30#include <assert.h>
31#include <fcntl.h>
32#include <sys/mman.h>
33#include <sys/param.h>
34#include <sys/types.h>
35#include <sys/stat.h>
36#include <string.h>
37#include <errno.h>
38#include <unistd.h>
39#include <stdlib.h>
40#include "../wcsmbs/wcsmbsload.h"
41#include "../iconv/gconv_charset.h"
42#include "../iconv/gconv_int.h"
43#include <shlib-compat.h>
44#include <not-cancel.h>
45#include <kernel-features.h>
46
47extern struct __gconv_trans_data __libio_translit attribute_hidden;
48
49/* An fstream can be in at most one of put mode, get mode, or putback mode.
50 Putback mode is a variant of get mode.
51
52 In a filebuf, there is only one current position, instead of two
53 separate get and put pointers. In get mode, the current position
54 is that of gptr(); in put mode that of pptr().
55
56 The position in the buffer that corresponds to the position
57 in external file system is normally _IO_read_end, except in putback
58 mode, when it is _IO_save_end and also when the file is in append mode,
59 since switching from read to write mode automatically sends the position in
60 the external file system to the end of file.
61 If the field _fb._offset is >= 0, it gives the offset in
62 the file as a whole corresponding to eGptr(). (?)
63
64 PUT MODE:
65 If a filebuf is in put mode, then all of _IO_read_ptr, _IO_read_end,
66 and _IO_read_base are equal to each other. These are usually equal
67 to _IO_buf_base, though not necessarily if we have switched from
68 get mode to put mode. (The reason is to maintain the invariant
69 that _IO_read_end corresponds to the external file position.)
70 _IO_write_base is non-NULL and usually equal to _IO_buf_base.
71 We also have _IO_write_end == _IO_buf_end, but only in fully buffered mode.
72 The un-flushed character are those between _IO_write_base and _IO_write_ptr.
73
74 GET MODE:
75 If a filebuf is in get or putback mode, eback() != egptr().
76 In get mode, the unread characters are between gptr() and egptr().
77 The OS file position corresponds to that of egptr().
78
79 PUTBACK MODE:
80 Putback mode is used to remember "excess" characters that have
81 been sputbackc'd in a separate putback buffer.
82 In putback mode, the get buffer points to the special putback buffer.
83 The unread characters are the characters between gptr() and egptr()
84 in the putback buffer, as well as the area between save_gptr()
85 and save_egptr(), which point into the original reserve buffer.
86 (The pointers save_gptr() and save_egptr() are the values
87 of gptr() and egptr() at the time putback mode was entered.)
88 The OS position corresponds to that of save_egptr().
89
90 LINE BUFFERED OUTPUT:
91 During line buffered output, _IO_write_base==base() && epptr()==base().
92 However, ptr() may be anywhere between base() and ebuf().
93 This forces a call to filebuf::overflow(int C) on every put.
94 If there is more space in the buffer, and C is not a '\n',
95 then C is inserted, and pptr() incremented.
96
97 UNBUFFERED STREAMS:
98 If a filebuf is unbuffered(), the _shortbuf[1] is used as the buffer.
99*/
100
101#define CLOSED_FILEBUF_FLAGS \
102 (_IO_IS_FILEBUF+_IO_NO_READS+_IO_NO_WRITES+_IO_TIED_PUT_GET)
103
104
105void
106_IO_new_file_init_internal (struct _IO_FILE_plus *fp)
107{
108 /* POSIX.1 allows another file handle to be used to change the position
109 of our file descriptor. Hence we actually don't know the actual
110 position before we do the first fseek (and until a following fflush). */
111 fp->file._offset = _IO_pos_BAD;
112 fp->file._flags |= CLOSED_FILEBUF_FLAGS;
113
114 _IO_link_in (fp);
115 fp->file._fileno = -1;
116}
117
118/* External version of _IO_new_file_init_internal which switches off
119 vtable validation. */
120void
121_IO_new_file_init (struct _IO_FILE_plus *fp)
122{
123 IO_set_accept_foreign_vtables (&_IO_vtable_check);
124 _IO_new_file_init_internal (fp);
125}
126
127int
128_IO_new_file_close_it (FILE *fp)
129{
130 int write_status;
131 if (!_IO_file_is_open (fp))
132 return EOF;
133
134 if ((fp->_flags & _IO_NO_WRITES) == 0
135 && (fp->_flags & _IO_CURRENTLY_PUTTING) != 0)
136 write_status = _IO_do_flush (fp);
137 else
138 write_status = 0;
139
140 _IO_unsave_markers (fp);
141
142 int close_status = ((fp->_flags2 & _IO_FLAGS2_NOCLOSE) == 0
143 ? _IO_SYSCLOSE (fp) : 0);
144
145 /* Free buffer. */
146 if (fp->_mode > 0)
147 {
148 if (_IO_have_wbackup (fp))
149 _IO_free_wbackup_area (fp);
150 _IO_wsetb (fp, NULL, NULL, 0);
151 _IO_wsetg (fp, NULL, NULL, NULL);
152 _IO_wsetp (fp, NULL, NULL);
153 }
154 _IO_setb (fp, NULL, NULL, 0);
155 _IO_setg (fp, NULL, NULL, NULL);
156 _IO_setp (fp, NULL, NULL);
157
158 _IO_un_link ((struct _IO_FILE_plus *) fp);
159 fp->_flags = _IO_MAGIC|CLOSED_FILEBUF_FLAGS;
160 fp->_fileno = -1;
161 fp->_offset = _IO_pos_BAD;
162
163 return close_status ? close_status : write_status;
164}
165libc_hidden_ver (_IO_new_file_close_it, _IO_file_close_it)
166
167void
168_IO_new_file_finish (FILE *fp, int dummy)
169{
170 if (_IO_file_is_open (fp))
171 {
172 _IO_do_flush (fp);
173 if (!(fp->_flags & _IO_DELETE_DONT_CLOSE))
174 _IO_SYSCLOSE (fp);
175 }
176 _IO_default_finish (fp, 0);
177}
178libc_hidden_ver (_IO_new_file_finish, _IO_file_finish)
179
180FILE *
181_IO_file_open (FILE *fp, const char *filename, int posix_mode, int prot,
182 int read_write, int is32not64)
183{
184 int fdesc;
185 if (__glibc_unlikely (fp->_flags2 & _IO_FLAGS2_NOTCANCEL))
186 fdesc = __open_nocancel (filename,
187 posix_mode | (is32not64 ? 0 : O_LARGEFILE), prot);
188 else
189 fdesc = __open (filename, posix_mode | (is32not64 ? 0 : O_LARGEFILE), prot);
190 if (fdesc < 0)
191 return NULL;
192 fp->_fileno = fdesc;
193 _IO_mask_flags (fp, read_write,_IO_NO_READS+_IO_NO_WRITES+_IO_IS_APPENDING);
194 /* For append mode, send the file offset to the end of the file. Don't
195 update the offset cache though, since the file handle is not active. */
196 if ((read_write & (_IO_IS_APPENDING | _IO_NO_READS))
197 == (_IO_IS_APPENDING | _IO_NO_READS))
198 {
199 off64_t new_pos = _IO_SYSSEEK (fp, 0, _IO_seek_end);
200 if (new_pos == _IO_pos_BAD && errno != ESPIPE)
201 {
202 __close_nocancel (fdesc);
203 return NULL;
204 }
205 }
206 _IO_link_in ((struct _IO_FILE_plus *) fp);
207 return fp;
208}
209libc_hidden_def (_IO_file_open)
210
211FILE *
212_IO_new_file_fopen (FILE *fp, const char *filename, const char *mode,
213 int is32not64)
214{
215 int oflags = 0, omode;
216 int read_write;
217 int oprot = 0666;
218 int i;
219 FILE *result;
220 const char *cs;
221 const char *last_recognized;
222
223 if (_IO_file_is_open (fp))
224 return 0;
225 switch (*mode)
226 {
227 case 'r':
228 omode = O_RDONLY;
229 read_write = _IO_NO_WRITES;
230 break;
231 case 'w':
232 omode = O_WRONLY;
233 oflags = O_CREAT|O_TRUNC;
234 read_write = _IO_NO_READS;
235 break;
236 case 'a':
237 omode = O_WRONLY;
238 oflags = O_CREAT|O_APPEND;
239 read_write = _IO_NO_READS|_IO_IS_APPENDING;
240 break;
241 default:
242 __set_errno (EINVAL);
243 return NULL;
244 }
245 last_recognized = mode;
246 for (i = 1; i < 7; ++i)
247 {
248 switch (*++mode)
249 {
250 case '\0':
251 break;
252 case '+':
253 omode = O_RDWR;
254 read_write &= _IO_IS_APPENDING;
255 last_recognized = mode;
256 continue;
257 case 'x':
258 oflags |= O_EXCL;
259 last_recognized = mode;
260 continue;
261 case 'b':
262 last_recognized = mode;
263 continue;
264 case 'm':
265 fp->_flags2 |= _IO_FLAGS2_MMAP;
266 continue;
267 case 'c':
268 fp->_flags2 |= _IO_FLAGS2_NOTCANCEL;
269 continue;
270 case 'e':
271 oflags |= O_CLOEXEC;
272 fp->_flags2 |= _IO_FLAGS2_CLOEXEC;
273 continue;
274 default:
275 /* Ignore. */
276 continue;
277 }
278 break;
279 }
280
281 result = _IO_file_open (fp, filename, omode|oflags, oprot, read_write,
282 is32not64);
283
284 if (result != NULL)
285 {
286 /* Test whether the mode string specifies the conversion. */
287 cs = strstr (last_recognized + 1, ",ccs=");
288 if (cs != NULL)
289 {
290 /* Yep. Load the appropriate conversions and set the orientation
291 to wide. */
292 struct gconv_fcts fcts;
293 struct _IO_codecvt *cc;
294 char *endp = __strchrnul (cs + 5, ',');
295 char *ccs = malloc (endp - (cs + 5) + 3);
296
297 if (ccs == NULL)
298 {
299 int malloc_err = errno; /* Whatever malloc failed with. */
300 (void) _IO_file_close_it (fp);
301 __set_errno (malloc_err);
302 return NULL;
303 }
304
305 *((char *) __mempcpy (ccs, cs + 5, endp - (cs + 5))) = '\0';
306 strip (ccs, ccs);
307
308 if (__wcsmbs_named_conv (&fcts, ccs[2] == '\0'
309 ? upstr (ccs, cs + 5) : ccs) != 0)
310 {
311 /* Something went wrong, we cannot load the conversion modules.
312 This means we cannot proceed since the user explicitly asked
313 for these. */
314 (void) _IO_file_close_it (fp);
315 free (ccs);
316 __set_errno (EINVAL);
317 return NULL;
318 }
319
320 free (ccs);
321
322 assert (fcts.towc_nsteps == 1);
323 assert (fcts.tomb_nsteps == 1);
324
325 fp->_wide_data->_IO_read_ptr = fp->_wide_data->_IO_read_end;
326 fp->_wide_data->_IO_write_ptr = fp->_wide_data->_IO_write_base;
327
328 /* Clear the state. We start all over again. */
329 memset (&fp->_wide_data->_IO_state, '\0', sizeof (__mbstate_t));
330 memset (&fp->_wide_data->_IO_last_state, '\0', sizeof (__mbstate_t));
331
332 cc = fp->_codecvt = &fp->_wide_data->_codecvt;
333
334 cc->__cd_in.step = fcts.towc;
335
336 cc->__cd_in.step_data.__invocation_counter = 0;
337 cc->__cd_in.step_data.__internal_use = 1;
338 cc->__cd_in.step_data.__flags = __GCONV_IS_LAST;
339 cc->__cd_in.step_data.__statep = &result->_wide_data->_IO_state;
340
341 cc->__cd_out.step = fcts.tomb;
342
343 cc->__cd_out.step_data.__invocation_counter = 0;
344 cc->__cd_out.step_data.__internal_use = 1;
345 cc->__cd_out.step_data.__flags = __GCONV_IS_LAST | __GCONV_TRANSLIT;
346 cc->__cd_out.step_data.__statep = &result->_wide_data->_IO_state;
347
348 /* From now on use the wide character callback functions. */
349 _IO_JUMPS_FILE_plus (fp) = fp->_wide_data->_wide_vtable;
350
351 /* Set the mode now. */
352 result->_mode = 1;
353 }
354 }
355
356 return result;
357}
358libc_hidden_ver (_IO_new_file_fopen, _IO_file_fopen)
359
360FILE *
361_IO_new_file_attach (FILE *fp, int fd)
362{
363 if (_IO_file_is_open (fp))
364 return NULL;
365 fp->_fileno = fd;
366 fp->_flags &= ~(_IO_NO_READS+_IO_NO_WRITES);
367 fp->_flags |= _IO_DELETE_DONT_CLOSE;
368 /* Get the current position of the file. */
369 /* We have to do that since that may be junk. */
370 fp->_offset = _IO_pos_BAD;
371 int save_errno = errno;
372 if (_IO_SEEKOFF (fp, (off64_t)0, _IO_seek_cur, _IOS_INPUT|_IOS_OUTPUT)
373 == _IO_pos_BAD && errno != ESPIPE)
374 return NULL;
375 __set_errno (save_errno);
376 return fp;
377}
378libc_hidden_ver (_IO_new_file_attach, _IO_file_attach)
379
380FILE *
381_IO_new_file_setbuf (FILE *fp, char *p, ssize_t len)
382{
383 if (_IO_default_setbuf (fp, p, len) == NULL)
384 return NULL;
385
386 fp->_IO_write_base = fp->_IO_write_ptr = fp->_IO_write_end
387 = fp->_IO_buf_base;
388 _IO_setg (fp, fp->_IO_buf_base, fp->_IO_buf_base, fp->_IO_buf_base);
389
390 return fp;
391}
392libc_hidden_ver (_IO_new_file_setbuf, _IO_file_setbuf)
393
394
395FILE *
396_IO_file_setbuf_mmap (FILE *fp, char *p, ssize_t len)
397{
398 FILE *result;
399
400 /* Change the function table. */
401 _IO_JUMPS_FILE_plus (fp) = &_IO_file_jumps;
402 fp->_wide_data->_wide_vtable = &_IO_wfile_jumps;
403
404 /* And perform the normal operation. */
405 result = _IO_new_file_setbuf (fp, p, len);
406
407 /* If the call failed, restore to using mmap. */
408 if (result == NULL)
409 {
410 _IO_JUMPS_FILE_plus (fp) = &_IO_file_jumps_mmap;
411 fp->_wide_data->_wide_vtable = &_IO_wfile_jumps_mmap;
412 }
413
414 return result;
415}
416
417static size_t new_do_write (FILE *, const char *, size_t);
418
419/* Write TO_DO bytes from DATA to FP.
420 Then mark FP as having empty buffers. */
421
422int
423_IO_new_do_write (FILE *fp, const char *data, size_t to_do)
424{
425 return (to_do == 0
426 || (size_t) new_do_write (fp, data, to_do) == to_do) ? 0 : EOF;
427}
428libc_hidden_ver (_IO_new_do_write, _IO_do_write)
429
430static size_t
431new_do_write (FILE *fp, const char *data, size_t to_do)
432{
433 size_t count;
434 if (fp->_flags & _IO_IS_APPENDING)
435 /* On a system without a proper O_APPEND implementation,
436 you would need to sys_seek(0, SEEK_END) here, but is
437 not needed nor desirable for Unix- or Posix-like systems.
438 Instead, just indicate that offset (before and after) is
439 unpredictable. */
440 fp->_offset = _IO_pos_BAD;
441 else if (fp->_IO_read_end != fp->_IO_write_base)
442 {
443 off64_t new_pos
444 = _IO_SYSSEEK (fp, fp->_IO_write_base - fp->_IO_read_end, 1);
445 if (new_pos == _IO_pos_BAD)
446 return 0;
447 fp->_offset = new_pos;
448 }
449 count = _IO_SYSWRITE (fp, data, to_do);
450 if (fp->_cur_column && count)
451 fp->_cur_column = _IO_adjust_column (fp->_cur_column - 1, data, count) + 1;
452 _IO_setg (fp, fp->_IO_buf_base, fp->_IO_buf_base, fp->_IO_buf_base);
453 fp->_IO_write_base = fp->_IO_write_ptr = fp->_IO_buf_base;
454 fp->_IO_write_end = (fp->_mode <= 0
455 && (fp->_flags & (_IO_LINE_BUF | _IO_UNBUFFERED))
456 ? fp->_IO_buf_base : fp->_IO_buf_end);
457 return count;
458}
459
460int
461_IO_new_file_underflow (FILE *fp)
462{
463 ssize_t count;
464
465 /* C99 requires EOF to be "sticky". */
466 if (fp->_flags & _IO_EOF_SEEN)
467 return EOF;
468
469 if (fp->_flags & _IO_NO_READS)
470 {
471 fp->_flags |= _IO_ERR_SEEN;
472 __set_errno (EBADF);
473 return EOF;
474 }
475 if (fp->_IO_read_ptr < fp->_IO_read_end)
476 return *(unsigned char *) fp->_IO_read_ptr;
477
478 if (fp->_IO_buf_base == NULL)
479 {
480 /* Maybe we already have a push back pointer. */
481 if (fp->_IO_save_base != NULL)
482 {
483 free (fp->_IO_save_base);
484 fp->_flags &= ~_IO_IN_BACKUP;
485 }
486 _IO_doallocbuf (fp);
487 }
488
489 /* FIXME This can/should be moved to genops ?? */
490 if (fp->_flags & (_IO_LINE_BUF|_IO_UNBUFFERED))
491 {
492 /* We used to flush all line-buffered stream. This really isn't
493 required by any standard. My recollection is that
494 traditional Unix systems did this for stdout. stderr better
495 not be line buffered. So we do just that here
496 explicitly. --drepper */
497 _IO_acquire_lock (stdout);
498
499 if ((stdout->_flags & (_IO_LINKED | _IO_NO_WRITES | _IO_LINE_BUF))
500 == (_IO_LINKED | _IO_LINE_BUF))
501 _IO_OVERFLOW (stdout, EOF);
502
503 _IO_release_lock (stdout);
504 }
505
506 _IO_switch_to_get_mode (fp);
507
508 /* This is very tricky. We have to adjust those
509 pointers before we call _IO_SYSREAD () since
510 we may longjump () out while waiting for
511 input. Those pointers may be screwed up. H.J. */
512 fp->_IO_read_base = fp->_IO_read_ptr = fp->_IO_buf_base;
513 fp->_IO_read_end = fp->_IO_buf_base;
514 fp->_IO_write_base = fp->_IO_write_ptr = fp->_IO_write_end
515 = fp->_IO_buf_base;
516
517 count = _IO_SYSREAD (fp, fp->_IO_buf_base,
518 fp->_IO_buf_end - fp->_IO_buf_base);
519 if (count <= 0)
520 {
521 if (count == 0)
522 fp->_flags |= _IO_EOF_SEEN;
523 else
524 fp->_flags |= _IO_ERR_SEEN, count = 0;
525 }
526 fp->_IO_read_end += count;
527 if (count == 0)
528 {
529 /* If a stream is read to EOF, the calling application may switch active
530 handles. As a result, our offset cache would no longer be valid, so
531 unset it. */
532 fp->_offset = _IO_pos_BAD;
533 return EOF;
534 }
535 if (fp->_offset != _IO_pos_BAD)
536 _IO_pos_adjust (fp->_offset, count);
537 return *(unsigned char *) fp->_IO_read_ptr;
538}
539libc_hidden_ver (_IO_new_file_underflow, _IO_file_underflow)
540
541/* Guts of underflow callback if we mmap the file. This stats the file and
542 updates the stream state to match. In the normal case we return zero.
543 If the file is no longer eligible for mmap, its jump tables are reset to
544 the vanilla ones and we return nonzero. */
545static int
546mmap_remap_check (FILE *fp)
547{
548 struct stat64 st;
549
550 if (_IO_SYSSTAT (fp, &st) == 0
551 && S_ISREG (st.st_mode) && st.st_size != 0
552 /* Limit the file size to 1MB for 32-bit machines. */
553 && (sizeof (ptrdiff_t) > 4 || st.st_size < 1*1024*1024))
554 {
555 const size_t pagesize = __getpagesize ();
556# define ROUNDED(x) (((x) + pagesize - 1) & ~(pagesize - 1))
557 if (ROUNDED (st.st_size) < ROUNDED (fp->_IO_buf_end
558 - fp->_IO_buf_base))
559 {
560 /* We can trim off some pages past the end of the file. */
561 (void) __munmap (fp->_IO_buf_base + ROUNDED (st.st_size),
562 ROUNDED (fp->_IO_buf_end - fp->_IO_buf_base)
563 - ROUNDED (st.st_size));
564 fp->_IO_buf_end = fp->_IO_buf_base + st.st_size;
565 }
566 else if (ROUNDED (st.st_size) > ROUNDED (fp->_IO_buf_end
567 - fp->_IO_buf_base))
568 {
569 /* The file added some pages. We need to remap it. */
570 void *p;
571#if _G_HAVE_MREMAP
572 p = __mremap (fp->_IO_buf_base, ROUNDED (fp->_IO_buf_end
573 - fp->_IO_buf_base),
574 ROUNDED (st.st_size), MREMAP_MAYMOVE);
575 if (p == MAP_FAILED)
576 {
577 (void) __munmap (fp->_IO_buf_base,
578 fp->_IO_buf_end - fp->_IO_buf_base);
579 goto punt;
580 }
581#else
582 (void) __munmap (fp->_IO_buf_base,
583 fp->_IO_buf_end - fp->_IO_buf_base);
584 p = __mmap64 (NULL, st.st_size, PROT_READ, MAP_SHARED,
585 fp->_fileno, 0);
586 if (p == MAP_FAILED)
587 goto punt;
588#endif
589 fp->_IO_buf_base = p;
590 fp->_IO_buf_end = fp->_IO_buf_base + st.st_size;
591 }
592 else
593 {
594 /* The number of pages didn't change. */
595 fp->_IO_buf_end = fp->_IO_buf_base + st.st_size;
596 }
597# undef ROUNDED
598
599 fp->_offset -= fp->_IO_read_end - fp->_IO_read_ptr;
600 _IO_setg (fp, fp->_IO_buf_base,
601 fp->_offset < fp->_IO_buf_end - fp->_IO_buf_base
602 ? fp->_IO_buf_base + fp->_offset : fp->_IO_buf_end,
603 fp->_IO_buf_end);
604
605 /* If we are already positioned at or past the end of the file, don't
606 change the current offset. If not, seek past what we have mapped,
607 mimicking the position left by a normal underflow reading into its
608 buffer until EOF. */
609
610 if (fp->_offset < fp->_IO_buf_end - fp->_IO_buf_base)
611 {
612 if (__lseek64 (fp->_fileno, fp->_IO_buf_end - fp->_IO_buf_base,
613 SEEK_SET)
614 != fp->_IO_buf_end - fp->_IO_buf_base)
615 fp->_flags |= _IO_ERR_SEEN;
616 else
617 fp->_offset = fp->_IO_buf_end - fp->_IO_buf_base;
618 }
619
620 return 0;
621 }
622 else
623 {
624 /* Life is no longer good for mmap. Punt it. */
625 (void) __munmap (fp->_IO_buf_base,
626 fp->_IO_buf_end - fp->_IO_buf_base);
627 punt:
628 fp->_IO_buf_base = fp->_IO_buf_end = NULL;
629 _IO_setg (fp, NULL, NULL, NULL);
630 if (fp->_mode <= 0)
631 _IO_JUMPS_FILE_plus (fp) = &_IO_file_jumps;
632 else
633 _IO_JUMPS_FILE_plus (fp) = &_IO_wfile_jumps;
634 fp->_wide_data->_wide_vtable = &_IO_wfile_jumps;
635
636 return 1;
637 }
638}
639
640/* Special callback replacing the underflow callbacks if we mmap the file. */
641int
642_IO_file_underflow_mmap (FILE *fp)
643{
644 if (fp->_IO_read_ptr < fp->_IO_read_end)
645 return *(unsigned char *) fp->_IO_read_ptr;
646
647 if (__glibc_unlikely (mmap_remap_check (fp)))
648 /* We punted to the regular file functions. */
649 return _IO_UNDERFLOW (fp);
650
651 if (fp->_IO_read_ptr < fp->_IO_read_end)
652 return *(unsigned char *) fp->_IO_read_ptr;
653
654 fp->_flags |= _IO_EOF_SEEN;
655 return EOF;
656}
657
658static void
659decide_maybe_mmap (FILE *fp)
660{
661 /* We use the file in read-only mode. This could mean we can
662 mmap the file and use it without any copying. But not all
663 file descriptors are for mmap-able objects and on 32-bit
664 machines we don't want to map files which are too large since
665 this would require too much virtual memory. */
666 struct stat64 st;
667
668 if (_IO_SYSSTAT (fp, &st) == 0
669 && S_ISREG (st.st_mode) && st.st_size != 0
670 /* Limit the file size to 1MB for 32-bit machines. */
671 && (sizeof (ptrdiff_t) > 4 || st.st_size < 1*1024*1024)
672 /* Sanity check. */
673 && (fp->_offset == _IO_pos_BAD || fp->_offset <= st.st_size))
674 {
675 /* Try to map the file. */
676 void *p;
677
678 p = __mmap64 (NULL, st.st_size, PROT_READ, MAP_SHARED, fp->_fileno, 0);
679 if (p != MAP_FAILED)
680 {
681 /* OK, we managed to map the file. Set the buffer up and use a
682 special jump table with simplified underflow functions which
683 never tries to read anything from the file. */
684
685 if (__lseek64 (fp->_fileno, st.st_size, SEEK_SET) != st.st_size)
686 {
687 (void) __munmap (p, st.st_size);
688 fp->_offset = _IO_pos_BAD;
689 }
690 else
691 {
692 _IO_setb (fp, p, (char *) p + st.st_size, 0);
693
694 if (fp->_offset == _IO_pos_BAD)
695 fp->_offset = 0;
696
697 _IO_setg (fp, p, p + fp->_offset, p + st.st_size);
698 fp->_offset = st.st_size;
699
700 if (fp->_mode <= 0)
701 _IO_JUMPS_FILE_plus (fp) = &_IO_file_jumps_mmap;
702 else
703 _IO_JUMPS_FILE_plus (fp) = &_IO_wfile_jumps_mmap;
704 fp->_wide_data->_wide_vtable = &_IO_wfile_jumps_mmap;
705
706 return;
707 }
708 }
709 }
710
711 /* We couldn't use mmap, so revert to the vanilla file operations. */
712
713 if (fp->_mode <= 0)
714 _IO_JUMPS_FILE_plus (fp) = &_IO_file_jumps;
715 else
716 _IO_JUMPS_FILE_plus (fp) = &_IO_wfile_jumps;
717 fp->_wide_data->_wide_vtable = &_IO_wfile_jumps;
718}
719
720int
721_IO_file_underflow_maybe_mmap (FILE *fp)
722{
723 /* This is the first read attempt. Choose mmap or vanilla operations
724 and then punt to the chosen underflow routine. */
725 decide_maybe_mmap (fp);
726 return _IO_UNDERFLOW (fp);
727}
728
729
730int
731_IO_new_file_overflow (FILE *f, int ch)
732{
733 if (f->_flags & _IO_NO_WRITES) /* SET ERROR */
734 {
735 f->_flags |= _IO_ERR_SEEN;
736 __set_errno (EBADF);
737 return EOF;
738 }
739 /* If currently reading or no buffer allocated. */
740 if ((f->_flags & _IO_CURRENTLY_PUTTING) == 0 || f->_IO_write_base == NULL)
741 {
742 /* Allocate a buffer if needed. */
743 if (f->_IO_write_base == NULL)
744 {
745 _IO_doallocbuf (f);
746 _IO_setg (f, f->_IO_buf_base, f->_IO_buf_base, f->_IO_buf_base);
747 }
748 /* Otherwise must be currently reading.
749 If _IO_read_ptr (and hence also _IO_read_end) is at the buffer end,
750 logically slide the buffer forwards one block (by setting the
751 read pointers to all point at the beginning of the block). This
752 makes room for subsequent output.
753 Otherwise, set the read pointers to _IO_read_end (leaving that
754 alone, so it can continue to correspond to the external position). */
755 if (__glibc_unlikely (_IO_in_backup (f)))
756 {
757 size_t nbackup = f->_IO_read_end - f->_IO_read_ptr;
758 _IO_free_backup_area (f);
759 f->_IO_read_base -= MIN (nbackup,
760 f->_IO_read_base - f->_IO_buf_base);
761 f->_IO_read_ptr = f->_IO_read_base;
762 }
763
764 if (f->_IO_read_ptr == f->_IO_buf_end)
765 f->_IO_read_end = f->_IO_read_ptr = f->_IO_buf_base;
766 f->_IO_write_ptr = f->_IO_read_ptr;
767 f->_IO_write_base = f->_IO_write_ptr;
768 f->_IO_write_end = f->_IO_buf_end;
769 f->_IO_read_base = f->_IO_read_ptr = f->_IO_read_end;
770
771 f->_flags |= _IO_CURRENTLY_PUTTING;
772 if (f->_mode <= 0 && f->_flags & (_IO_LINE_BUF | _IO_UNBUFFERED))
773 f->_IO_write_end = f->_IO_write_ptr;
774 }
775 if (ch == EOF)
776 return _IO_do_write (f, f->_IO_write_base,
777 f->_IO_write_ptr - f->_IO_write_base);
778 if (f->_IO_write_ptr == f->_IO_buf_end ) /* Buffer is really full */
779 if (_IO_do_flush (f) == EOF)
780 return EOF;
781 *f->_IO_write_ptr++ = ch;
782 if ((f->_flags & _IO_UNBUFFERED)
783 || ((f->_flags & _IO_LINE_BUF) && ch == '\n'))
784 if (_IO_do_write (f, f->_IO_write_base,
785 f->_IO_write_ptr - f->_IO_write_base) == EOF)
786 return EOF;
787 return (unsigned char) ch;
788}
789libc_hidden_ver (_IO_new_file_overflow, _IO_file_overflow)
790
791int
792_IO_new_file_sync (FILE *fp)
793{
794 ssize_t delta;
795 int retval = 0;
796
797 /* char* ptr = cur_ptr(); */
798 if (fp->_IO_write_ptr > fp->_IO_write_base)
799 if (_IO_do_flush(fp)) return EOF;
800 delta = fp->_IO_read_ptr - fp->_IO_read_end;
801 if (delta != 0)
802 {
803 off64_t new_pos = _IO_SYSSEEK (fp, delta, 1);
804 if (new_pos != (off64_t) EOF)
805 fp->_IO_read_end = fp->_IO_read_ptr;
806 else if (errno == ESPIPE)
807 ; /* Ignore error from unseekable devices. */
808 else
809 retval = EOF;
810 }
811 if (retval != EOF)
812 fp->_offset = _IO_pos_BAD;
813 /* FIXME: Cleanup - can this be shared? */
814 /* setg(base(), ptr, ptr); */
815 return retval;
816}
817libc_hidden_ver (_IO_new_file_sync, _IO_file_sync)
818
819static int
820_IO_file_sync_mmap (FILE *fp)
821{
822 if (fp->_IO_read_ptr != fp->_IO_read_end)
823 {
824 if (__lseek64 (fp->_fileno, fp->_IO_read_ptr - fp->_IO_buf_base,
825 SEEK_SET)
826 != fp->_IO_read_ptr - fp->_IO_buf_base)
827 {
828 fp->_flags |= _IO_ERR_SEEN;
829 return EOF;
830 }
831 }
832 fp->_offset = fp->_IO_read_ptr - fp->_IO_buf_base;
833 fp->_IO_read_end = fp->_IO_read_ptr = fp->_IO_read_base;
834 return 0;
835}
836
837/* ftell{,o} implementation. The only time we modify the state of the stream
838 is when we have unflushed writes. In that case we seek to the end and
839 record that offset in the stream object. */
840static off64_t
841do_ftell (FILE *fp)
842{
843 off64_t result, offset = 0;
844
845 /* No point looking at unflushed data if we haven't allocated buffers
846 yet. */
847 if (fp->_IO_buf_base != NULL)
848 {
849 bool unflushed_writes = fp->_IO_write_ptr > fp->_IO_write_base;
850
851 bool append_mode = (fp->_flags & _IO_IS_APPENDING) == _IO_IS_APPENDING;
852
853 /* When we have unflushed writes in append mode, seek to the end of the
854 file and record that offset. This is the only time we change the file
855 stream state and it is safe since the file handle is active. */
856 if (unflushed_writes && append_mode)
857 {
858 result = _IO_SYSSEEK (fp, 0, _IO_seek_end);
859 if (result == _IO_pos_BAD)
860 return EOF;
861 else
862 fp->_offset = result;
863 }
864
865 /* Adjust for unflushed data. */
866 if (!unflushed_writes)
867 offset -= fp->_IO_read_end - fp->_IO_read_ptr;
868 /* We don't trust _IO_read_end to represent the current file offset when
869 writing in append mode because the value would have to be shifted to
870 the end of the file during a flush. Use the write base instead, along
871 with the new offset we got above when we did a seek to the end of the
872 file. */
873 else if (append_mode)
874 offset += fp->_IO_write_ptr - fp->_IO_write_base;
875 /* For all other modes, _IO_read_end represents the file offset. */
876 else
877 offset += fp->_IO_write_ptr - fp->_IO_read_end;
878 }
879
880 if (fp->_offset != _IO_pos_BAD)
881 result = fp->_offset;
882 else
883 result = _IO_SYSSEEK (fp, 0, _IO_seek_cur);
884
885 if (result == EOF)
886 return result;
887
888 result += offset;
889
890 if (result < 0)
891 {
892 __set_errno (EINVAL);
893 return EOF;
894 }
895
896 return result;
897}
898
899off64_t
900_IO_new_file_seekoff (FILE *fp, off64_t offset, int dir, int mode)
901{
902 off64_t result;
903 off64_t delta, new_offset;
904 long count;
905
906 /* Short-circuit into a separate function. We don't want to mix any
907 functionality and we don't want to touch anything inside the FILE
908 object. */
909 if (mode == 0)
910 return do_ftell (fp);
911
912 /* POSIX.1 8.2.3.7 says that after a call the fflush() the file
913 offset of the underlying file must be exact. */
914 int must_be_exact = (fp->_IO_read_base == fp->_IO_read_end
915 && fp->_IO_write_base == fp->_IO_write_ptr);
916
917 bool was_writing = (fp->_IO_write_ptr > fp->_IO_write_base
918 || _IO_in_put_mode (fp));
919
920 /* Flush unwritten characters.
921 (This may do an unneeded write if we seek within the buffer.
922 But to be able to switch to reading, we would need to set
923 egptr to pptr. That can't be done in the current design,
924 which assumes file_ptr() is eGptr. Anyway, since we probably
925 end up flushing when we close(), it doesn't make much difference.)
926 FIXME: simulate mem-mapped files. */
927 if (was_writing && _IO_switch_to_get_mode (fp))
928 return EOF;
929
930 if (fp->_IO_buf_base == NULL)
931 {
932 /* It could be that we already have a pushback buffer. */
933 if (fp->_IO_read_base != NULL)
934 {
935 free (fp->_IO_read_base);
936 fp->_flags &= ~_IO_IN_BACKUP;
937 }
938 _IO_doallocbuf (fp);
939 _IO_setp (fp, fp->_IO_buf_base, fp->_IO_buf_base);
940 _IO_setg (fp, fp->_IO_buf_base, fp->_IO_buf_base, fp->_IO_buf_base);
941 }
942
943 switch (dir)
944 {
945 case _IO_seek_cur:
946 /* Adjust for read-ahead (bytes is buffer). */
947 offset -= fp->_IO_read_end - fp->_IO_read_ptr;
948
949 if (fp->_offset == _IO_pos_BAD)
950 goto dumb;
951 /* Make offset absolute, assuming current pointer is file_ptr(). */
952 offset += fp->_offset;
953 if (offset < 0)
954 {
955 __set_errno (EINVAL);
956 return EOF;
957 }
958
959 dir = _IO_seek_set;
960 break;
961 case _IO_seek_set:
962 break;
963 case _IO_seek_end:
964 {
965 struct stat64 st;
966 if (_IO_SYSSTAT (fp, &st) == 0 && S_ISREG (st.st_mode))
967 {
968 offset += st.st_size;
969 dir = _IO_seek_set;
970 }
971 else
972 goto dumb;
973 }
974 }
975
976 _IO_free_backup_area (fp);
977
978 /* At this point, dir==_IO_seek_set. */
979
980 /* If destination is within current buffer, optimize: */
981 if (fp->_offset != _IO_pos_BAD && fp->_IO_read_base != NULL
982 && !_IO_in_backup (fp))
983 {
984 off64_t start_offset = (fp->_offset
985 - (fp->_IO_read_end - fp->_IO_buf_base));
986 if (offset >= start_offset && offset < fp->_offset)
987 {
988 _IO_setg (fp, fp->_IO_buf_base,
989 fp->_IO_buf_base + (offset - start_offset),
990 fp->_IO_read_end);
991 _IO_setp (fp, fp->_IO_buf_base, fp->_IO_buf_base);
992
993 _IO_mask_flags (fp, 0, _IO_EOF_SEEN);
994 goto resync;
995 }
996 }
997
998 if (fp->_flags & _IO_NO_READS)
999 goto dumb;
1000
1001 /* Try to seek to a block boundary, to improve kernel page management. */
1002 new_offset = offset & ~(fp->_IO_buf_end - fp->_IO_buf_base - 1);
1003 delta = offset - new_offset;
1004 if (delta > fp->_IO_buf_end - fp->_IO_buf_base)
1005 {
1006 new_offset = offset;
1007 delta = 0;
1008 }
1009 result = _IO_SYSSEEK (fp, new_offset, 0);
1010 if (result < 0)
1011 return EOF;
1012 if (delta == 0)
1013 count = 0;
1014 else
1015 {
1016 count = _IO_SYSREAD (fp, fp->_IO_buf_base,
1017 (must_be_exact
1018 ? delta : fp->_IO_buf_end - fp->_IO_buf_base));
1019 if (count < delta)
1020 {
1021 /* We weren't allowed to read, but try to seek the remainder. */
1022 offset = count == EOF ? delta : delta-count;
1023 dir = _IO_seek_cur;
1024 goto dumb;
1025 }
1026 }
1027 _IO_setg (fp, fp->_IO_buf_base, fp->_IO_buf_base + delta,
1028 fp->_IO_buf_base + count);
1029 _IO_setp (fp, fp->_IO_buf_base, fp->_IO_buf_base);
1030 fp->_offset = result + count;
1031 _IO_mask_flags (fp, 0, _IO_EOF_SEEN);
1032 return offset;
1033 dumb:
1034
1035 _IO_unsave_markers (fp);
1036 result = _IO_SYSSEEK (fp, offset, dir);
1037 if (result != EOF)
1038 {
1039 _IO_mask_flags (fp, 0, _IO_EOF_SEEN);
1040 fp->_offset = result;
1041 _IO_setg (fp, fp->_IO_buf_base, fp->_IO_buf_base, fp->_IO_buf_base);
1042 _IO_setp (fp, fp->_IO_buf_base, fp->_IO_buf_base);
1043 }
1044 return result;
1045
1046resync:
1047 /* We need to do it since it is possible that the file offset in
1048 the kernel may be changed behind our back. It may happen when
1049 we fopen a file and then do a fork. One process may access the
1050 file and the kernel file offset will be changed. */
1051 if (fp->_offset >= 0)
1052 _IO_SYSSEEK (fp, fp->_offset, 0);
1053
1054 return offset;
1055}
1056libc_hidden_ver (_IO_new_file_seekoff, _IO_file_seekoff)
1057
1058off64_t
1059_IO_file_seekoff_mmap (FILE *fp, off64_t offset, int dir, int mode)
1060{
1061 off64_t result;
1062
1063 /* If we are only interested in the current position, calculate it and
1064 return right now. This calculation does the right thing when we are
1065 using a pushback buffer, but in the usual case has the same value as
1066 (fp->_IO_read_ptr - fp->_IO_buf_base). */
1067 if (mode == 0)
1068 return fp->_offset - (fp->_IO_read_end - fp->_IO_read_ptr);
1069
1070 switch (dir)
1071 {
1072 case _IO_seek_cur:
1073 /* Adjust for read-ahead (bytes is buffer). */
1074 offset += fp->_IO_read_ptr - fp->_IO_read_base;
1075 break;
1076 case _IO_seek_set:
1077 break;
1078 case _IO_seek_end:
1079 offset += fp->_IO_buf_end - fp->_IO_buf_base;
1080 break;
1081 }
1082 /* At this point, dir==_IO_seek_set. */
1083
1084 if (offset < 0)
1085 {
1086 /* No negative offsets are valid. */
1087 __set_errno (EINVAL);
1088 return EOF;
1089 }
1090
1091 result = _IO_SYSSEEK (fp, offset, 0);
1092 if (result < 0)
1093 return EOF;
1094
1095 if (offset > fp->_IO_buf_end - fp->_IO_buf_base)
1096 /* One can fseek arbitrarily past the end of the file
1097 and it is meaningless until one attempts to read.
1098 Leave the buffer pointers in EOF state until underflow. */
1099 _IO_setg (fp, fp->_IO_buf_base, fp->_IO_buf_end, fp->_IO_buf_end);
1100 else
1101 /* Adjust the read pointers to match the file position,
1102 but so the next read attempt will call underflow. */
1103 _IO_setg (fp, fp->_IO_buf_base, fp->_IO_buf_base + offset,
1104 fp->_IO_buf_base + offset);
1105
1106 fp->_offset = result;
1107
1108 _IO_mask_flags (fp, 0, _IO_EOF_SEEN);
1109
1110 return offset;
1111}
1112
1113static off64_t
1114_IO_file_seekoff_maybe_mmap (FILE *fp, off64_t offset, int dir,
1115 int mode)
1116{
1117 /* We only get here when we haven't tried to read anything yet.
1118 So there is nothing more useful for us to do here than just
1119 the underlying lseek call. */
1120
1121 off64_t result = _IO_SYSSEEK (fp, offset, dir);
1122 if (result < 0)
1123 return EOF;
1124
1125 fp->_offset = result;
1126 return result;
1127}
1128
1129ssize_t
1130_IO_file_read (FILE *fp, void *buf, ssize_t size)
1131{
1132 return (__builtin_expect (fp->_flags2 & _IO_FLAGS2_NOTCANCEL, 0)
1133 ? __read_nocancel (fp->_fileno, buf, size)
1134 : __read (fp->_fileno, buf, size));
1135}
1136libc_hidden_def (_IO_file_read)
1137
1138off64_t
1139_IO_file_seek (FILE *fp, off64_t offset, int dir)
1140{
1141 return __lseek64 (fp->_fileno, offset, dir);
1142}
1143libc_hidden_def (_IO_file_seek)
1144
1145int
1146_IO_file_stat (FILE *fp, void *st)
1147{
1148 return __fxstat64 (_STAT_VER, fp->_fileno, (struct stat64 *) st);
1149}
1150libc_hidden_def (_IO_file_stat)
1151
1152int
1153_IO_file_close_mmap (FILE *fp)
1154{
1155 /* In addition to closing the file descriptor we have to unmap the file. */
1156 (void) __munmap (fp->_IO_buf_base, fp->_IO_buf_end - fp->_IO_buf_base);
1157 fp->_IO_buf_base = fp->_IO_buf_end = NULL;
1158 /* Cancelling close should be avoided if possible since it leaves an
1159 unrecoverable state behind. */
1160 return __close_nocancel (fp->_fileno);
1161}
1162
1163int
1164_IO_file_close (FILE *fp)
1165{
1166 /* Cancelling close should be avoided if possible since it leaves an
1167 unrecoverable state behind. */
1168 return __close_nocancel (fp->_fileno);
1169}
1170libc_hidden_def (_IO_file_close)
1171
1172ssize_t
1173_IO_new_file_write (FILE *f, const void *data, ssize_t n)
1174{
1175 ssize_t to_do = n;
1176 while (to_do > 0)
1177 {
1178 ssize_t count = (__builtin_expect (f->_flags2
1179 & _IO_FLAGS2_NOTCANCEL, 0)
1180 ? __write_nocancel (f->_fileno, data, to_do)
1181 : __write (f->_fileno, data, to_do));
1182 if (count < 0)
1183 {
1184 f->_flags |= _IO_ERR_SEEN;
1185 break;
1186 }
1187 to_do -= count;
1188 data = (void *) ((char *) data + count);
1189 }
1190 n -= to_do;
1191 if (f->_offset >= 0)
1192 f->_offset += n;
1193 return n;
1194}
1195
1196size_t
1197_IO_new_file_xsputn (FILE *f, const void *data, size_t n)
1198{
1199 const char *s = (const char *) data;
1200 size_t to_do = n;
1201 int must_flush = 0;
1202 size_t count = 0;
1203
1204 if (n <= 0)
1205 return 0;
1206 /* This is an optimized implementation.
1207 If the amount to be written straddles a block boundary
1208 (or the filebuf is unbuffered), use sys_write directly. */
1209
1210 /* First figure out how much space is available in the buffer. */
1211 if ((f->_flags & _IO_LINE_BUF) && (f->_flags & _IO_CURRENTLY_PUTTING))
1212 {
1213 count = f->_IO_buf_end - f->_IO_write_ptr;
1214 if (count >= n)
1215 {
1216 const char *p;
1217 for (p = s + n; p > s; )
1218 {
1219 if (*--p == '\n')
1220 {
1221 count = p - s + 1;
1222 must_flush = 1;
1223 break;
1224 }
1225 }
1226 }
1227 }
1228 else if (f->_IO_write_end > f->_IO_write_ptr)
1229 count = f->_IO_write_end - f->_IO_write_ptr; /* Space available. */
1230
1231 /* Then fill the buffer. */
1232 if (count > 0)
1233 {
1234 if (count > to_do)
1235 count = to_do;
1236 f->_IO_write_ptr = __mempcpy (f->_IO_write_ptr, s, count);
1237 s += count;
1238 to_do -= count;
1239 }
1240 if (to_do + must_flush > 0)
1241 {
1242 size_t block_size, do_write;
1243 /* Next flush the (full) buffer. */
1244 if (_IO_OVERFLOW (f, EOF) == EOF)
1245 /* If nothing else has to be written we must not signal the
1246 caller that everything has been written. */
1247 return to_do == 0 ? EOF : n - to_do;
1248
1249 /* Try to maintain alignment: write a whole number of blocks. */
1250 block_size = f->_IO_buf_end - f->_IO_buf_base;
1251 do_write = to_do - (block_size >= 128 ? to_do % block_size : 0);
1252
1253 if (do_write)
1254 {
1255 count = new_do_write (f, s, do_write);
1256 to_do -= count;
1257 if (count < do_write)
1258 return n - to_do;
1259 }
1260
1261 /* Now write out the remainder. Normally, this will fit in the
1262 buffer, but it's somewhat messier for line-buffered files,
1263 so we let _IO_default_xsputn handle the general case. */
1264 if (to_do)
1265 to_do -= _IO_default_xsputn (f, s+do_write, to_do);
1266 }
1267 return n - to_do;
1268}
1269libc_hidden_ver (_IO_new_file_xsputn, _IO_file_xsputn)
1270
1271size_t
1272_IO_file_xsgetn (FILE *fp, void *data, size_t n)
1273{
1274 size_t want, have;
1275 ssize_t count;
1276 char *s = data;
1277
1278 want = n;
1279
1280 if (fp->_IO_buf_base == NULL)
1281 {
1282 /* Maybe we already have a push back pointer. */
1283 if (fp->_IO_save_base != NULL)
1284 {
1285 free (fp->_IO_save_base);
1286 fp->_flags &= ~_IO_IN_BACKUP;
1287 }
1288 _IO_doallocbuf (fp);
1289 }
1290
1291 while (want > 0)
1292 {
1293 have = fp->_IO_read_end - fp->_IO_read_ptr;
1294 if (want <= have)
1295 {
1296 memcpy (s, fp->_IO_read_ptr, want);
1297 fp->_IO_read_ptr += want;
1298 want = 0;
1299 }
1300 else
1301 {
1302 if (have > 0)
1303 {
1304 s = __mempcpy (s, fp->_IO_read_ptr, have);
1305 want -= have;
1306 fp->_IO_read_ptr += have;
1307 }
1308
1309 /* Check for backup and repeat */
1310 if (_IO_in_backup (fp))
1311 {
1312 _IO_switch_to_main_get_area (fp);
1313 continue;
1314 }
1315
1316 /* If we now want less than a buffer, underflow and repeat
1317 the copy. Otherwise, _IO_SYSREAD directly to
1318 the user buffer. */
1319 if (fp->_IO_buf_base
1320 && want < (size_t) (fp->_IO_buf_end - fp->_IO_buf_base))
1321 {
1322 if (__underflow (fp) == EOF)
1323 break;
1324
1325 continue;
1326 }
1327
1328 /* These must be set before the sysread as we might longjmp out
1329 waiting for input. */
1330 _IO_setg (fp, fp->_IO_buf_base, fp->_IO_buf_base, fp->_IO_buf_base);
1331 _IO_setp (fp, fp->_IO_buf_base, fp->_IO_buf_base);
1332
1333 /* Try to maintain alignment: read a whole number of blocks. */
1334 count = want;
1335 if (fp->_IO_buf_base)
1336 {
1337 size_t block_size = fp->_IO_buf_end - fp->_IO_buf_base;
1338 if (block_size >= 128)
1339 count -= want % block_size;
1340 }
1341
1342 count = _IO_SYSREAD (fp, s, count);
1343 if (count <= 0)
1344 {
1345 if (count == 0)
1346 fp->_flags |= _IO_EOF_SEEN;
1347 else
1348 fp->_flags |= _IO_ERR_SEEN;
1349
1350 break;
1351 }
1352
1353 s += count;
1354 want -= count;
1355 if (fp->_offset != _IO_pos_BAD)
1356 _IO_pos_adjust (fp->_offset, count);
1357 }
1358 }
1359
1360 return n - want;
1361}
1362libc_hidden_def (_IO_file_xsgetn)
1363
1364static size_t
1365_IO_file_xsgetn_mmap (FILE *fp, void *data, size_t n)
1366{
1367 size_t have;
1368 char *read_ptr = fp->_IO_read_ptr;
1369 char *s = (char *) data;
1370
1371 have = fp->_IO_read_end - fp->_IO_read_ptr;
1372
1373 if (have < n)
1374 {
1375 if (__glibc_unlikely (_IO_in_backup (fp)))
1376 {
1377 s = __mempcpy (s, read_ptr, have);
1378 n -= have;
1379 _IO_switch_to_main_get_area (fp);
1380 read_ptr = fp->_IO_read_ptr;
1381 have = fp->_IO_read_end - fp->_IO_read_ptr;
1382 }
1383
1384 if (have < n)
1385 {
1386 /* Check that we are mapping all of the file, in case it grew. */
1387 if (__glibc_unlikely (mmap_remap_check (fp)))
1388 /* We punted mmap, so complete with the vanilla code. */
1389 return s - (char *) data + _IO_XSGETN (fp, data, n);
1390
1391 read_ptr = fp->_IO_read_ptr;
1392 have = fp->_IO_read_end - read_ptr;
1393 }
1394 }
1395
1396 if (have < n)
1397 fp->_flags |= _IO_EOF_SEEN;
1398
1399 if (have != 0)
1400 {
1401 have = MIN (have, n);
1402 s = __mempcpy (s, read_ptr, have);
1403 fp->_IO_read_ptr = read_ptr + have;
1404 }
1405
1406 return s - (char *) data;
1407}
1408
1409static size_t
1410_IO_file_xsgetn_maybe_mmap (FILE *fp, void *data, size_t n)
1411{
1412 /* We only get here if this is the first attempt to read something.
1413 Decide which operations to use and then punt to the chosen one. */
1414
1415 decide_maybe_mmap (fp);
1416 return _IO_XSGETN (fp, data, n);
1417}
1418
1419versioned_symbol (libc, _IO_new_do_write, _IO_do_write, GLIBC_2_1);
1420versioned_symbol (libc, _IO_new_file_attach, _IO_file_attach, GLIBC_2_1);
1421versioned_symbol (libc, _IO_new_file_close_it, _IO_file_close_it, GLIBC_2_1);
1422versioned_symbol (libc, _IO_new_file_finish, _IO_file_finish, GLIBC_2_1);
1423versioned_symbol (libc, _IO_new_file_fopen, _IO_file_fopen, GLIBC_2_1);
1424versioned_symbol (libc, _IO_new_file_init, _IO_file_init, GLIBC_2_1);
1425versioned_symbol (libc, _IO_new_file_setbuf, _IO_file_setbuf, GLIBC_2_1);
1426versioned_symbol (libc, _IO_new_file_sync, _IO_file_sync, GLIBC_2_1);
1427versioned_symbol (libc, _IO_new_file_overflow, _IO_file_overflow, GLIBC_2_1);
1428versioned_symbol (libc, _IO_new_file_seekoff, _IO_file_seekoff, GLIBC_2_1);
1429versioned_symbol (libc, _IO_new_file_underflow, _IO_file_underflow, GLIBC_2_1);
1430versioned_symbol (libc, _IO_new_file_write, _IO_file_write, GLIBC_2_1);
1431versioned_symbol (libc, _IO_new_file_xsputn, _IO_file_xsputn, GLIBC_2_1);
1432
1433const struct _IO_jump_t _IO_file_jumps libio_vtable =
1434{
1435 JUMP_INIT_DUMMY,
1436 JUMP_INIT(finish, _IO_file_finish),
1437 JUMP_INIT(overflow, _IO_file_overflow),
1438 JUMP_INIT(underflow, _IO_file_underflow),
1439 JUMP_INIT(uflow, _IO_default_uflow),
1440 JUMP_INIT(pbackfail, _IO_default_pbackfail),
1441 JUMP_INIT(xsputn, _IO_file_xsputn),
1442 JUMP_INIT(xsgetn, _IO_file_xsgetn),
1443 JUMP_INIT(seekoff, _IO_new_file_seekoff),
1444 JUMP_INIT(seekpos, _IO_default_seekpos),
1445 JUMP_INIT(setbuf, _IO_new_file_setbuf),
1446 JUMP_INIT(sync, _IO_new_file_sync),
1447 JUMP_INIT(doallocate, _IO_file_doallocate),
1448 JUMP_INIT(read, _IO_file_read),
1449 JUMP_INIT(write, _IO_new_file_write),
1450 JUMP_INIT(seek, _IO_file_seek),
1451 JUMP_INIT(close, _IO_file_close),
1452 JUMP_INIT(stat, _IO_file_stat),
1453 JUMP_INIT(showmanyc, _IO_default_showmanyc),
1454 JUMP_INIT(imbue, _IO_default_imbue)
1455};
1456libc_hidden_data_def (_IO_file_jumps)
1457
1458const struct _IO_jump_t _IO_file_jumps_mmap libio_vtable =
1459{
1460 JUMP_INIT_DUMMY,
1461 JUMP_INIT(finish, _IO_file_finish),
1462 JUMP_INIT(overflow, _IO_file_overflow),
1463 JUMP_INIT(underflow, _IO_file_underflow_mmap),
1464 JUMP_INIT(uflow, _IO_default_uflow),
1465 JUMP_INIT(pbackfail, _IO_default_pbackfail),
1466 JUMP_INIT(xsputn, _IO_new_file_xsputn),
1467 JUMP_INIT(xsgetn, _IO_file_xsgetn_mmap),
1468 JUMP_INIT(seekoff, _IO_file_seekoff_mmap),
1469 JUMP_INIT(seekpos, _IO_default_seekpos),
1470 JUMP_INIT(setbuf, (_IO_setbuf_t) _IO_file_setbuf_mmap),
1471 JUMP_INIT(sync, _IO_file_sync_mmap),
1472 JUMP_INIT(doallocate, _IO_file_doallocate),
1473 JUMP_INIT(read, _IO_file_read),
1474 JUMP_INIT(write, _IO_new_file_write),
1475 JUMP_INIT(seek, _IO_file_seek),
1476 JUMP_INIT(close, _IO_file_close_mmap),
1477 JUMP_INIT(stat, _IO_file_stat),
1478 JUMP_INIT(showmanyc, _IO_default_showmanyc),
1479 JUMP_INIT(imbue, _IO_default_imbue)
1480};
1481
1482const struct _IO_jump_t _IO_file_jumps_maybe_mmap libio_vtable =
1483{
1484 JUMP_INIT_DUMMY,
1485 JUMP_INIT(finish, _IO_file_finish),
1486 JUMP_INIT(overflow, _IO_file_overflow),
1487 JUMP_INIT(underflow, _IO_file_underflow_maybe_mmap),
1488 JUMP_INIT(uflow, _IO_default_uflow),
1489 JUMP_INIT(pbackfail, _IO_default_pbackfail),
1490 JUMP_INIT(xsputn, _IO_new_file_xsputn),
1491 JUMP_INIT(xsgetn, _IO_file_xsgetn_maybe_mmap),
1492 JUMP_INIT(seekoff, _IO_file_seekoff_maybe_mmap),
1493 JUMP_INIT(seekpos, _IO_default_seekpos),
1494 JUMP_INIT(setbuf, (_IO_setbuf_t) _IO_file_setbuf_mmap),
1495 JUMP_INIT(sync, _IO_new_file_sync),
1496 JUMP_INIT(doallocate, _IO_file_doallocate),
1497 JUMP_INIT(read, _IO_file_read),
1498 JUMP_INIT(write, _IO_new_file_write),
1499 JUMP_INIT(seek, _IO_file_seek),
1500 JUMP_INIT(close, _IO_file_close),
1501 JUMP_INIT(stat, _IO_file_stat),
1502 JUMP_INIT(showmanyc, _IO_default_showmanyc),
1503 JUMP_INIT(imbue, _IO_default_imbue)
1504};
1505