1/* Copyright (C) 1993-2018 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 <http://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 /* The functions are always the same. */
335 *cc = __libio_codecvt;
336
337 cc->__cd_in.__cd.__nsteps = fcts.towc_nsteps;
338 cc->__cd_in.__cd.__steps = fcts.towc;
339
340 cc->__cd_in.__cd.__data[0].__invocation_counter = 0;
341 cc->__cd_in.__cd.__data[0].__internal_use = 1;
342 cc->__cd_in.__cd.__data[0].__flags = __GCONV_IS_LAST;
343 cc->__cd_in.__cd.__data[0].__statep = &result->_wide_data->_IO_state;
344
345 cc->__cd_out.__cd.__nsteps = fcts.tomb_nsteps;
346 cc->__cd_out.__cd.__steps = fcts.tomb;
347
348 cc->__cd_out.__cd.__data[0].__invocation_counter = 0;
349 cc->__cd_out.__cd.__data[0].__internal_use = 1;
350 cc->__cd_out.__cd.__data[0].__flags
351 = __GCONV_IS_LAST | __GCONV_TRANSLIT;
352 cc->__cd_out.__cd.__data[0].__statep =
353 &result->_wide_data->_IO_state;
354
355 /* From now on use the wide character callback functions. */
356 _IO_JUMPS_FILE_plus (fp) = fp->_wide_data->_wide_vtable;
357
358 /* Set the mode now. */
359 result->_mode = 1;
360 }
361 }
362
363 return result;
364}
365libc_hidden_ver (_IO_new_file_fopen, _IO_file_fopen)
366
367FILE *
368_IO_new_file_attach (FILE *fp, int fd)
369{
370 if (_IO_file_is_open (fp))
371 return NULL;
372 fp->_fileno = fd;
373 fp->_flags &= ~(_IO_NO_READS+_IO_NO_WRITES);
374 fp->_flags |= _IO_DELETE_DONT_CLOSE;
375 /* Get the current position of the file. */
376 /* We have to do that since that may be junk. */
377 fp->_offset = _IO_pos_BAD;
378 int save_errno = errno;
379 if (_IO_SEEKOFF (fp, (off64_t)0, _IO_seek_cur, _IOS_INPUT|_IOS_OUTPUT)
380 == _IO_pos_BAD && errno != ESPIPE)
381 return NULL;
382 __set_errno (save_errno);
383 return fp;
384}
385libc_hidden_ver (_IO_new_file_attach, _IO_file_attach)
386
387FILE *
388_IO_new_file_setbuf (FILE *fp, char *p, ssize_t len)
389{
390 if (_IO_default_setbuf (fp, p, len) == NULL)
391 return NULL;
392
393 fp->_IO_write_base = fp->_IO_write_ptr = fp->_IO_write_end
394 = fp->_IO_buf_base;
395 _IO_setg (fp, fp->_IO_buf_base, fp->_IO_buf_base, fp->_IO_buf_base);
396
397 return fp;
398}
399libc_hidden_ver (_IO_new_file_setbuf, _IO_file_setbuf)
400
401
402FILE *
403_IO_file_setbuf_mmap (FILE *fp, char *p, ssize_t len)
404{
405 FILE *result;
406
407 /* Change the function table. */
408 _IO_JUMPS_FILE_plus (fp) = &_IO_file_jumps;
409 fp->_wide_data->_wide_vtable = &_IO_wfile_jumps;
410
411 /* And perform the normal operation. */
412 result = _IO_new_file_setbuf (fp, p, len);
413
414 /* If the call failed, restore to using mmap. */
415 if (result == NULL)
416 {
417 _IO_JUMPS_FILE_plus (fp) = &_IO_file_jumps_mmap;
418 fp->_wide_data->_wide_vtable = &_IO_wfile_jumps_mmap;
419 }
420
421 return result;
422}
423
424static size_t new_do_write (FILE *, const char *, size_t);
425
426/* Write TO_DO bytes from DATA to FP.
427 Then mark FP as having empty buffers. */
428
429int
430_IO_new_do_write (FILE *fp, const char *data, size_t to_do)
431{
432 return (to_do == 0
433 || (size_t) new_do_write (fp, data, to_do) == to_do) ? 0 : EOF;
434}
435libc_hidden_ver (_IO_new_do_write, _IO_do_write)
436
437static size_t
438new_do_write (FILE *fp, const char *data, size_t to_do)
439{
440 size_t count;
441 if (fp->_flags & _IO_IS_APPENDING)
442 /* On a system without a proper O_APPEND implementation,
443 you would need to sys_seek(0, SEEK_END) here, but is
444 not needed nor desirable for Unix- or Posix-like systems.
445 Instead, just indicate that offset (before and after) is
446 unpredictable. */
447 fp->_offset = _IO_pos_BAD;
448 else if (fp->_IO_read_end != fp->_IO_write_base)
449 {
450 off64_t new_pos
451 = _IO_SYSSEEK (fp, fp->_IO_write_base - fp->_IO_read_end, 1);
452 if (new_pos == _IO_pos_BAD)
453 return 0;
454 fp->_offset = new_pos;
455 }
456 count = _IO_SYSWRITE (fp, data, to_do);
457 if (fp->_cur_column && count)
458 fp->_cur_column = _IO_adjust_column (fp->_cur_column - 1, data, count) + 1;
459 _IO_setg (fp, fp->_IO_buf_base, fp->_IO_buf_base, fp->_IO_buf_base);
460 fp->_IO_write_base = fp->_IO_write_ptr = fp->_IO_buf_base;
461 fp->_IO_write_end = (fp->_mode <= 0
462 && (fp->_flags & (_IO_LINE_BUF | _IO_UNBUFFERED))
463 ? fp->_IO_buf_base : fp->_IO_buf_end);
464 return count;
465}
466
467int
468_IO_new_file_underflow (FILE *fp)
469{
470 ssize_t count;
471
472 /* C99 requires EOF to be "sticky". */
473 if (fp->_flags & _IO_EOF_SEEN)
474 return EOF;
475
476 if (fp->_flags & _IO_NO_READS)
477 {
478 fp->_flags |= _IO_ERR_SEEN;
479 __set_errno (EBADF);
480 return EOF;
481 }
482 if (fp->_IO_read_ptr < fp->_IO_read_end)
483 return *(unsigned char *) fp->_IO_read_ptr;
484
485 if (fp->_IO_buf_base == NULL)
486 {
487 /* Maybe we already have a push back pointer. */
488 if (fp->_IO_save_base != NULL)
489 {
490 free (fp->_IO_save_base);
491 fp->_flags &= ~_IO_IN_BACKUP;
492 }
493 _IO_doallocbuf (fp);
494 }
495
496 /* FIXME This can/should be moved to genops ?? */
497 if (fp->_flags & (_IO_LINE_BUF|_IO_UNBUFFERED))
498 {
499 /* We used to flush all line-buffered stream. This really isn't
500 required by any standard. My recollection is that
501 traditional Unix systems did this for stdout. stderr better
502 not be line buffered. So we do just that here
503 explicitly. --drepper */
504 _IO_acquire_lock (_IO_stdout);
505
506 if ((_IO_stdout->_flags & (_IO_LINKED | _IO_NO_WRITES | _IO_LINE_BUF))
507 == (_IO_LINKED | _IO_LINE_BUF))
508 _IO_OVERFLOW (_IO_stdout, EOF);
509
510 _IO_release_lock (_IO_stdout);
511 }
512
513 _IO_switch_to_get_mode (fp);
514
515 /* This is very tricky. We have to adjust those
516 pointers before we call _IO_SYSREAD () since
517 we may longjump () out while waiting for
518 input. Those pointers may be screwed up. H.J. */
519 fp->_IO_read_base = fp->_IO_read_ptr = fp->_IO_buf_base;
520 fp->_IO_read_end = fp->_IO_buf_base;
521 fp->_IO_write_base = fp->_IO_write_ptr = fp->_IO_write_end
522 = fp->_IO_buf_base;
523
524 count = _IO_SYSREAD (fp, fp->_IO_buf_base,
525 fp->_IO_buf_end - fp->_IO_buf_base);
526 if (count <= 0)
527 {
528 if (count == 0)
529 fp->_flags |= _IO_EOF_SEEN;
530 else
531 fp->_flags |= _IO_ERR_SEEN, count = 0;
532 }
533 fp->_IO_read_end += count;
534 if (count == 0)
535 {
536 /* If a stream is read to EOF, the calling application may switch active
537 handles. As a result, our offset cache would no longer be valid, so
538 unset it. */
539 fp->_offset = _IO_pos_BAD;
540 return EOF;
541 }
542 if (fp->_offset != _IO_pos_BAD)
543 _IO_pos_adjust (fp->_offset, count);
544 return *(unsigned char *) fp->_IO_read_ptr;
545}
546libc_hidden_ver (_IO_new_file_underflow, _IO_file_underflow)
547
548/* Guts of underflow callback if we mmap the file. This stats the file and
549 updates the stream state to match. In the normal case we return zero.
550 If the file is no longer eligible for mmap, its jump tables are reset to
551 the vanilla ones and we return nonzero. */
552static int
553mmap_remap_check (FILE *fp)
554{
555 struct stat64 st;
556
557 if (_IO_SYSSTAT (fp, &st) == 0
558 && S_ISREG (st.st_mode) && st.st_size != 0
559 /* Limit the file size to 1MB for 32-bit machines. */
560 && (sizeof (ptrdiff_t) > 4 || st.st_size < 1*1024*1024))
561 {
562 const size_t pagesize = __getpagesize ();
563# define ROUNDED(x) (((x) + pagesize - 1) & ~(pagesize - 1))
564 if (ROUNDED (st.st_size) < ROUNDED (fp->_IO_buf_end
565 - fp->_IO_buf_base))
566 {
567 /* We can trim off some pages past the end of the file. */
568 (void) __munmap (fp->_IO_buf_base + ROUNDED (st.st_size),
569 ROUNDED (fp->_IO_buf_end - fp->_IO_buf_base)
570 - ROUNDED (st.st_size));
571 fp->_IO_buf_end = fp->_IO_buf_base + st.st_size;
572 }
573 else if (ROUNDED (st.st_size) > ROUNDED (fp->_IO_buf_end
574 - fp->_IO_buf_base))
575 {
576 /* The file added some pages. We need to remap it. */
577 void *p;
578#if _G_HAVE_MREMAP
579 p = __mremap (fp->_IO_buf_base, ROUNDED (fp->_IO_buf_end
580 - fp->_IO_buf_base),
581 ROUNDED (st.st_size), MREMAP_MAYMOVE);
582 if (p == MAP_FAILED)
583 {
584 (void) __munmap (fp->_IO_buf_base,
585 fp->_IO_buf_end - fp->_IO_buf_base);
586 goto punt;
587 }
588#else
589 (void) __munmap (fp->_IO_buf_base,
590 fp->_IO_buf_end - fp->_IO_buf_base);
591 p = __mmap64 (NULL, st.st_size, PROT_READ, MAP_SHARED,
592 fp->_fileno, 0);
593 if (p == MAP_FAILED)
594 goto punt;
595#endif
596 fp->_IO_buf_base = p;
597 fp->_IO_buf_end = fp->_IO_buf_base + st.st_size;
598 }
599 else
600 {
601 /* The number of pages didn't change. */
602 fp->_IO_buf_end = fp->_IO_buf_base + st.st_size;
603 }
604# undef ROUNDED
605
606 fp->_offset -= fp->_IO_read_end - fp->_IO_read_ptr;
607 _IO_setg (fp, fp->_IO_buf_base,
608 fp->_offset < fp->_IO_buf_end - fp->_IO_buf_base
609 ? fp->_IO_buf_base + fp->_offset : fp->_IO_buf_end,
610 fp->_IO_buf_end);
611
612 /* If we are already positioned at or past the end of the file, don't
613 change the current offset. If not, seek past what we have mapped,
614 mimicking the position left by a normal underflow reading into its
615 buffer until EOF. */
616
617 if (fp->_offset < fp->_IO_buf_end - fp->_IO_buf_base)
618 {
619 if (__lseek64 (fp->_fileno, fp->_IO_buf_end - fp->_IO_buf_base,
620 SEEK_SET)
621 != fp->_IO_buf_end - fp->_IO_buf_base)
622 fp->_flags |= _IO_ERR_SEEN;
623 else
624 fp->_offset = fp->_IO_buf_end - fp->_IO_buf_base;
625 }
626
627 return 0;
628 }
629 else
630 {
631 /* Life is no longer good for mmap. Punt it. */
632 (void) __munmap (fp->_IO_buf_base,
633 fp->_IO_buf_end - fp->_IO_buf_base);
634 punt:
635 fp->_IO_buf_base = fp->_IO_buf_end = NULL;
636 _IO_setg (fp, NULL, NULL, NULL);
637 if (fp->_mode <= 0)
638 _IO_JUMPS_FILE_plus (fp) = &_IO_file_jumps;
639 else
640 _IO_JUMPS_FILE_plus (fp) = &_IO_wfile_jumps;
641 fp->_wide_data->_wide_vtable = &_IO_wfile_jumps;
642
643 return 1;
644 }
645}
646
647/* Special callback replacing the underflow callbacks if we mmap the file. */
648int
649_IO_file_underflow_mmap (FILE *fp)
650{
651 if (fp->_IO_read_ptr < fp->_IO_read_end)
652 return *(unsigned char *) fp->_IO_read_ptr;
653
654 if (__glibc_unlikely (mmap_remap_check (fp)))
655 /* We punted to the regular file functions. */
656 return _IO_UNDERFLOW (fp);
657
658 if (fp->_IO_read_ptr < fp->_IO_read_end)
659 return *(unsigned char *) fp->_IO_read_ptr;
660
661 fp->_flags |= _IO_EOF_SEEN;
662 return EOF;
663}
664
665static void
666decide_maybe_mmap (FILE *fp)
667{
668 /* We use the file in read-only mode. This could mean we can
669 mmap the file and use it without any copying. But not all
670 file descriptors are for mmap-able objects and on 32-bit
671 machines we don't want to map files which are too large since
672 this would require too much virtual memory. */
673 struct stat64 st;
674
675 if (_IO_SYSSTAT (fp, &st) == 0
676 && S_ISREG (st.st_mode) && st.st_size != 0
677 /* Limit the file size to 1MB for 32-bit machines. */
678 && (sizeof (ptrdiff_t) > 4 || st.st_size < 1*1024*1024)
679 /* Sanity check. */
680 && (fp->_offset == _IO_pos_BAD || fp->_offset <= st.st_size))
681 {
682 /* Try to map the file. */
683 void *p;
684
685 p = __mmap64 (NULL, st.st_size, PROT_READ, MAP_SHARED, fp->_fileno, 0);
686 if (p != MAP_FAILED)
687 {
688 /* OK, we managed to map the file. Set the buffer up and use a
689 special jump table with simplified underflow functions which
690 never tries to read anything from the file. */
691
692 if (__lseek64 (fp->_fileno, st.st_size, SEEK_SET) != st.st_size)
693 {
694 (void) __munmap (p, st.st_size);
695 fp->_offset = _IO_pos_BAD;
696 }
697 else
698 {
699 _IO_setb (fp, p, (char *) p + st.st_size, 0);
700
701 if (fp->_offset == _IO_pos_BAD)
702 fp->_offset = 0;
703
704 _IO_setg (fp, p, p + fp->_offset, p + st.st_size);
705 fp->_offset = st.st_size;
706
707 if (fp->_mode <= 0)
708 _IO_JUMPS_FILE_plus (fp) = &_IO_file_jumps_mmap;
709 else
710 _IO_JUMPS_FILE_plus (fp) = &_IO_wfile_jumps_mmap;
711 fp->_wide_data->_wide_vtable = &_IO_wfile_jumps_mmap;
712
713 return;
714 }
715 }
716 }
717
718 /* We couldn't use mmap, so revert to the vanilla file operations. */
719
720 if (fp->_mode <= 0)
721 _IO_JUMPS_FILE_plus (fp) = &_IO_file_jumps;
722 else
723 _IO_JUMPS_FILE_plus (fp) = &_IO_wfile_jumps;
724 fp->_wide_data->_wide_vtable = &_IO_wfile_jumps;
725}
726
727int
728_IO_file_underflow_maybe_mmap (FILE *fp)
729{
730 /* This is the first read attempt. Choose mmap or vanilla operations
731 and then punt to the chosen underflow routine. */
732 decide_maybe_mmap (fp);
733 return _IO_UNDERFLOW (fp);
734}
735
736
737int
738_IO_new_file_overflow (FILE *f, int ch)
739{
740 if (f->_flags & _IO_NO_WRITES) /* SET ERROR */
741 {
742 f->_flags |= _IO_ERR_SEEN;
743 __set_errno (EBADF);
744 return EOF;
745 }
746 /* If currently reading or no buffer allocated. */
747 if ((f->_flags & _IO_CURRENTLY_PUTTING) == 0 || f->_IO_write_base == NULL)
748 {
749 /* Allocate a buffer if needed. */
750 if (f->_IO_write_base == NULL)
751 {
752 _IO_doallocbuf (f);
753 _IO_setg (f, f->_IO_buf_base, f->_IO_buf_base, f->_IO_buf_base);
754 }
755 /* Otherwise must be currently reading.
756 If _IO_read_ptr (and hence also _IO_read_end) is at the buffer end,
757 logically slide the buffer forwards one block (by setting the
758 read pointers to all point at the beginning of the block). This
759 makes room for subsequent output.
760 Otherwise, set the read pointers to _IO_read_end (leaving that
761 alone, so it can continue to correspond to the external position). */
762 if (__glibc_unlikely (_IO_in_backup (f)))
763 {
764 size_t nbackup = f->_IO_read_end - f->_IO_read_ptr;
765 _IO_free_backup_area (f);
766 f->_IO_read_base -= MIN (nbackup,
767 f->_IO_read_base - f->_IO_buf_base);
768 f->_IO_read_ptr = f->_IO_read_base;
769 }
770
771 if (f->_IO_read_ptr == f->_IO_buf_end)
772 f->_IO_read_end = f->_IO_read_ptr = f->_IO_buf_base;
773 f->_IO_write_ptr = f->_IO_read_ptr;
774 f->_IO_write_base = f->_IO_write_ptr;
775 f->_IO_write_end = f->_IO_buf_end;
776 f->_IO_read_base = f->_IO_read_ptr = f->_IO_read_end;
777
778 f->_flags |= _IO_CURRENTLY_PUTTING;
779 if (f->_mode <= 0 && f->_flags & (_IO_LINE_BUF | _IO_UNBUFFERED))
780 f->_IO_write_end = f->_IO_write_ptr;
781 }
782 if (ch == EOF)
783 return _IO_do_write (f, f->_IO_write_base,
784 f->_IO_write_ptr - f->_IO_write_base);
785 if (f->_IO_write_ptr == f->_IO_buf_end ) /* Buffer is really full */
786 if (_IO_do_flush (f) == EOF)
787 return EOF;
788 *f->_IO_write_ptr++ = ch;
789 if ((f->_flags & _IO_UNBUFFERED)
790 || ((f->_flags & _IO_LINE_BUF) && ch == '\n'))
791 if (_IO_do_write (f, f->_IO_write_base,
792 f->_IO_write_ptr - f->_IO_write_base) == EOF)
793 return EOF;
794 return (unsigned char) ch;
795}
796libc_hidden_ver (_IO_new_file_overflow, _IO_file_overflow)
797
798int
799_IO_new_file_sync (FILE *fp)
800{
801 ssize_t delta;
802 int retval = 0;
803
804 /* char* ptr = cur_ptr(); */
805 if (fp->_IO_write_ptr > fp->_IO_write_base)
806 if (_IO_do_flush(fp)) return EOF;
807 delta = fp->_IO_read_ptr - fp->_IO_read_end;
808 if (delta != 0)
809 {
810 off64_t new_pos = _IO_SYSSEEK (fp, delta, 1);
811 if (new_pos != (off64_t) EOF)
812 fp->_IO_read_end = fp->_IO_read_ptr;
813 else if (errno == ESPIPE)
814 ; /* Ignore error from unseekable devices. */
815 else
816 retval = EOF;
817 }
818 if (retval != EOF)
819 fp->_offset = _IO_pos_BAD;
820 /* FIXME: Cleanup - can this be shared? */
821 /* setg(base(), ptr, ptr); */
822 return retval;
823}
824libc_hidden_ver (_IO_new_file_sync, _IO_file_sync)
825
826static int
827_IO_file_sync_mmap (FILE *fp)
828{
829 if (fp->_IO_read_ptr != fp->_IO_read_end)
830 {
831 if (__lseek64 (fp->_fileno, fp->_IO_read_ptr - fp->_IO_buf_base,
832 SEEK_SET)
833 != fp->_IO_read_ptr - fp->_IO_buf_base)
834 {
835 fp->_flags |= _IO_ERR_SEEN;
836 return EOF;
837 }
838 }
839 fp->_offset = fp->_IO_read_ptr - fp->_IO_buf_base;
840 fp->_IO_read_end = fp->_IO_read_ptr = fp->_IO_read_base;
841 return 0;
842}
843
844/* ftell{,o} implementation. The only time we modify the state of the stream
845 is when we have unflushed writes. In that case we seek to the end and
846 record that offset in the stream object. */
847static off64_t
848do_ftell (FILE *fp)
849{
850 off64_t result, offset = 0;
851
852 /* No point looking at unflushed data if we haven't allocated buffers
853 yet. */
854 if (fp->_IO_buf_base != NULL)
855 {
856 bool unflushed_writes = fp->_IO_write_ptr > fp->_IO_write_base;
857
858 bool append_mode = (fp->_flags & _IO_IS_APPENDING) == _IO_IS_APPENDING;
859
860 /* When we have unflushed writes in append mode, seek to the end of the
861 file and record that offset. This is the only time we change the file
862 stream state and it is safe since the file handle is active. */
863 if (unflushed_writes && append_mode)
864 {
865 result = _IO_SYSSEEK (fp, 0, _IO_seek_end);
866 if (result == _IO_pos_BAD)
867 return EOF;
868 else
869 fp->_offset = result;
870 }
871
872 /* Adjust for unflushed data. */
873 if (!unflushed_writes)
874 offset -= fp->_IO_read_end - fp->_IO_read_ptr;
875 /* We don't trust _IO_read_end to represent the current file offset when
876 writing in append mode because the value would have to be shifted to
877 the end of the file during a flush. Use the write base instead, along
878 with the new offset we got above when we did a seek to the end of the
879 file. */
880 else if (append_mode)
881 offset += fp->_IO_write_ptr - fp->_IO_write_base;
882 /* For all other modes, _IO_read_end represents the file offset. */
883 else
884 offset += fp->_IO_write_ptr - fp->_IO_read_end;
885 }
886
887 if (fp->_offset != _IO_pos_BAD)
888 result = fp->_offset;
889 else
890 result = _IO_SYSSEEK (fp, 0, _IO_seek_cur);
891
892 if (result == EOF)
893 return result;
894
895 result += offset;
896
897 if (result < 0)
898 {
899 __set_errno (EINVAL);
900 return EOF;
901 }
902
903 return result;
904}
905
906off64_t
907_IO_new_file_seekoff (FILE *fp, off64_t offset, int dir, int mode)
908{
909 off64_t result;
910 off64_t delta, new_offset;
911 long count;
912
913 /* Short-circuit into a separate function. We don't want to mix any
914 functionality and we don't want to touch anything inside the FILE
915 object. */
916 if (mode == 0)
917 return do_ftell (fp);
918
919 /* POSIX.1 8.2.3.7 says that after a call the fflush() the file
920 offset of the underlying file must be exact. */
921 int must_be_exact = (fp->_IO_read_base == fp->_IO_read_end
922 && fp->_IO_write_base == fp->_IO_write_ptr);
923
924 bool was_writing = (fp->_IO_write_ptr > fp->_IO_write_base
925 || _IO_in_put_mode (fp));
926
927 /* Flush unwritten characters.
928 (This may do an unneeded write if we seek within the buffer.
929 But to be able to switch to reading, we would need to set
930 egptr to pptr. That can't be done in the current design,
931 which assumes file_ptr() is eGptr. Anyway, since we probably
932 end up flushing when we close(), it doesn't make much difference.)
933 FIXME: simulate mem-mapped files. */
934 if (was_writing && _IO_switch_to_get_mode (fp))
935 return EOF;
936
937 if (fp->_IO_buf_base == NULL)
938 {
939 /* It could be that we already have a pushback buffer. */
940 if (fp->_IO_read_base != NULL)
941 {
942 free (fp->_IO_read_base);
943 fp->_flags &= ~_IO_IN_BACKUP;
944 }
945 _IO_doallocbuf (fp);
946 _IO_setp (fp, fp->_IO_buf_base, fp->_IO_buf_base);
947 _IO_setg (fp, fp->_IO_buf_base, fp->_IO_buf_base, fp->_IO_buf_base);
948 }
949
950 switch (dir)
951 {
952 case _IO_seek_cur:
953 /* Adjust for read-ahead (bytes is buffer). */
954 offset -= fp->_IO_read_end - fp->_IO_read_ptr;
955
956 if (fp->_offset == _IO_pos_BAD)
957 goto dumb;
958 /* Make offset absolute, assuming current pointer is file_ptr(). */
959 offset += fp->_offset;
960 if (offset < 0)
961 {
962 __set_errno (EINVAL);
963 return EOF;
964 }
965
966 dir = _IO_seek_set;
967 break;
968 case _IO_seek_set:
969 break;
970 case _IO_seek_end:
971 {
972 struct stat64 st;
973 if (_IO_SYSSTAT (fp, &st) == 0 && S_ISREG (st.st_mode))
974 {
975 offset += st.st_size;
976 dir = _IO_seek_set;
977 }
978 else
979 goto dumb;
980 }
981 }
982
983 _IO_free_backup_area (fp);
984
985 /* At this point, dir==_IO_seek_set. */
986
987 /* If destination is within current buffer, optimize: */
988 if (fp->_offset != _IO_pos_BAD && fp->_IO_read_base != NULL
989 && !_IO_in_backup (fp))
990 {
991 off64_t start_offset = (fp->_offset
992 - (fp->_IO_read_end - fp->_IO_buf_base));
993 if (offset >= start_offset && offset < fp->_offset)
994 {
995 _IO_setg (fp, fp->_IO_buf_base,
996 fp->_IO_buf_base + (offset - start_offset),
997 fp->_IO_read_end);
998 _IO_setp (fp, fp->_IO_buf_base, fp->_IO_buf_base);
999
1000 _IO_mask_flags (fp, 0, _IO_EOF_SEEN);
1001 goto resync;
1002 }
1003 }
1004
1005 if (fp->_flags & _IO_NO_READS)
1006 goto dumb;
1007
1008 /* Try to seek to a block boundary, to improve kernel page management. */
1009 new_offset = offset & ~(fp->_IO_buf_end - fp->_IO_buf_base - 1);
1010 delta = offset - new_offset;
1011 if (delta > fp->_IO_buf_end - fp->_IO_buf_base)
1012 {
1013 new_offset = offset;
1014 delta = 0;
1015 }
1016 result = _IO_SYSSEEK (fp, new_offset, 0);
1017 if (result < 0)
1018 return EOF;
1019 if (delta == 0)
1020 count = 0;
1021 else
1022 {
1023 count = _IO_SYSREAD (fp, fp->_IO_buf_base,
1024 (must_be_exact
1025 ? delta : fp->_IO_buf_end - fp->_IO_buf_base));
1026 if (count < delta)
1027 {
1028 /* We weren't allowed to read, but try to seek the remainder. */
1029 offset = count == EOF ? delta : delta-count;
1030 dir = _IO_seek_cur;
1031 goto dumb;
1032 }
1033 }
1034 _IO_setg (fp, fp->_IO_buf_base, fp->_IO_buf_base + delta,
1035 fp->_IO_buf_base + count);
1036 _IO_setp (fp, fp->_IO_buf_base, fp->_IO_buf_base);
1037 fp->_offset = result + count;
1038 _IO_mask_flags (fp, 0, _IO_EOF_SEEN);
1039 return offset;
1040 dumb:
1041
1042 _IO_unsave_markers (fp);
1043 result = _IO_SYSSEEK (fp, offset, dir);
1044 if (result != EOF)
1045 {
1046 _IO_mask_flags (fp, 0, _IO_EOF_SEEN);
1047 fp->_offset = result;
1048 _IO_setg (fp, fp->_IO_buf_base, fp->_IO_buf_base, fp->_IO_buf_base);
1049 _IO_setp (fp, fp->_IO_buf_base, fp->_IO_buf_base);
1050 }
1051 return result;
1052
1053resync:
1054 /* We need to do it since it is possible that the file offset in
1055 the kernel may be changed behind our back. It may happen when
1056 we fopen a file and then do a fork. One process may access the
1057 file and the kernel file offset will be changed. */
1058 if (fp->_offset >= 0)
1059 _IO_SYSSEEK (fp, fp->_offset, 0);
1060
1061 return offset;
1062}
1063libc_hidden_ver (_IO_new_file_seekoff, _IO_file_seekoff)
1064
1065off64_t
1066_IO_file_seekoff_mmap (FILE *fp, off64_t offset, int dir, int mode)
1067{
1068 off64_t result;
1069
1070 /* If we are only interested in the current position, calculate it and
1071 return right now. This calculation does the right thing when we are
1072 using a pushback buffer, but in the usual case has the same value as
1073 (fp->_IO_read_ptr - fp->_IO_buf_base). */
1074 if (mode == 0)
1075 return fp->_offset - (fp->_IO_read_end - fp->_IO_read_ptr);
1076
1077 switch (dir)
1078 {
1079 case _IO_seek_cur:
1080 /* Adjust for read-ahead (bytes is buffer). */
1081 offset += fp->_IO_read_ptr - fp->_IO_read_base;
1082 break;
1083 case _IO_seek_set:
1084 break;
1085 case _IO_seek_end:
1086 offset += fp->_IO_buf_end - fp->_IO_buf_base;
1087 break;
1088 }
1089 /* At this point, dir==_IO_seek_set. */
1090
1091 if (offset < 0)
1092 {
1093 /* No negative offsets are valid. */
1094 __set_errno (EINVAL);
1095 return EOF;
1096 }
1097
1098 result = _IO_SYSSEEK (fp, offset, 0);
1099 if (result < 0)
1100 return EOF;
1101
1102 if (offset > fp->_IO_buf_end - fp->_IO_buf_base)
1103 /* One can fseek arbitrarily past the end of the file
1104 and it is meaningless until one attempts to read.
1105 Leave the buffer pointers in EOF state until underflow. */
1106 _IO_setg (fp, fp->_IO_buf_base, fp->_IO_buf_end, fp->_IO_buf_end);
1107 else
1108 /* Adjust the read pointers to match the file position,
1109 but so the next read attempt will call underflow. */
1110 _IO_setg (fp, fp->_IO_buf_base, fp->_IO_buf_base + offset,
1111 fp->_IO_buf_base + offset);
1112
1113 fp->_offset = result;
1114
1115 _IO_mask_flags (fp, 0, _IO_EOF_SEEN);
1116
1117 return offset;
1118}
1119
1120static off64_t
1121_IO_file_seekoff_maybe_mmap (FILE *fp, off64_t offset, int dir,
1122 int mode)
1123{
1124 /* We only get here when we haven't tried to read anything yet.
1125 So there is nothing more useful for us to do here than just
1126 the underlying lseek call. */
1127
1128 off64_t result = _IO_SYSSEEK (fp, offset, dir);
1129 if (result < 0)
1130 return EOF;
1131
1132 fp->_offset = result;
1133 return result;
1134}
1135
1136ssize_t
1137_IO_file_read (FILE *fp, void *buf, ssize_t size)
1138{
1139 return (__builtin_expect (fp->_flags2 & _IO_FLAGS2_NOTCANCEL, 0)
1140 ? __read_nocancel (fp->_fileno, buf, size)
1141 : __read (fp->_fileno, buf, size));
1142}
1143libc_hidden_def (_IO_file_read)
1144
1145off64_t
1146_IO_file_seek (FILE *fp, off64_t offset, int dir)
1147{
1148 return __lseek64 (fp->_fileno, offset, dir);
1149}
1150libc_hidden_def (_IO_file_seek)
1151
1152int
1153_IO_file_stat (FILE *fp, void *st)
1154{
1155 return __fxstat64 (_STAT_VER, fp->_fileno, (struct stat64 *) st);
1156}
1157libc_hidden_def (_IO_file_stat)
1158
1159int
1160_IO_file_close_mmap (FILE *fp)
1161{
1162 /* In addition to closing the file descriptor we have to unmap the file. */
1163 (void) __munmap (fp->_IO_buf_base, fp->_IO_buf_end - fp->_IO_buf_base);
1164 fp->_IO_buf_base = fp->_IO_buf_end = NULL;
1165 /* Cancelling close should be avoided if possible since it leaves an
1166 unrecoverable state behind. */
1167 return __close_nocancel (fp->_fileno);
1168}
1169
1170int
1171_IO_file_close (FILE *fp)
1172{
1173 /* Cancelling close should be avoided if possible since it leaves an
1174 unrecoverable state behind. */
1175 return __close_nocancel (fp->_fileno);
1176}
1177libc_hidden_def (_IO_file_close)
1178
1179ssize_t
1180_IO_new_file_write (FILE *f, const void *data, ssize_t n)
1181{
1182 ssize_t to_do = n;
1183 while (to_do > 0)
1184 {
1185 ssize_t count = (__builtin_expect (f->_flags2
1186 & _IO_FLAGS2_NOTCANCEL, 0)
1187 ? __write_nocancel (f->_fileno, data, to_do)
1188 : __write (f->_fileno, data, to_do));
1189 if (count < 0)
1190 {
1191 f->_flags |= _IO_ERR_SEEN;
1192 break;
1193 }
1194 to_do -= count;
1195 data = (void *) ((char *) data + count);
1196 }
1197 n -= to_do;
1198 if (f->_offset >= 0)
1199 f->_offset += n;
1200 return n;
1201}
1202
1203size_t
1204_IO_new_file_xsputn (FILE *f, const void *data, size_t n)
1205{
1206 const char *s = (const char *) data;
1207 size_t to_do = n;
1208 int must_flush = 0;
1209 size_t count = 0;
1210
1211 if (n <= 0)
1212 return 0;
1213 /* This is an optimized implementation.
1214 If the amount to be written straddles a block boundary
1215 (or the filebuf is unbuffered), use sys_write directly. */
1216
1217 /* First figure out how much space is available in the buffer. */
1218 if ((f->_flags & _IO_LINE_BUF) && (f->_flags & _IO_CURRENTLY_PUTTING))
1219 {
1220 count = f->_IO_buf_end - f->_IO_write_ptr;
1221 if (count >= n)
1222 {
1223 const char *p;
1224 for (p = s + n; p > s; )
1225 {
1226 if (*--p == '\n')
1227 {
1228 count = p - s + 1;
1229 must_flush = 1;
1230 break;
1231 }
1232 }
1233 }
1234 }
1235 else if (f->_IO_write_end > f->_IO_write_ptr)
1236 count = f->_IO_write_end - f->_IO_write_ptr; /* Space available. */
1237
1238 /* Then fill the buffer. */
1239 if (count > 0)
1240 {
1241 if (count > to_do)
1242 count = to_do;
1243 f->_IO_write_ptr = __mempcpy (f->_IO_write_ptr, s, count);
1244 s += count;
1245 to_do -= count;
1246 }
1247 if (to_do + must_flush > 0)
1248 {
1249 size_t block_size, do_write;
1250 /* Next flush the (full) buffer. */
1251 if (_IO_OVERFLOW (f, EOF) == EOF)
1252 /* If nothing else has to be written we must not signal the
1253 caller that everything has been written. */
1254 return to_do == 0 ? EOF : n - to_do;
1255
1256 /* Try to maintain alignment: write a whole number of blocks. */
1257 block_size = f->_IO_buf_end - f->_IO_buf_base;
1258 do_write = to_do - (block_size >= 128 ? to_do % block_size : 0);
1259
1260 if (do_write)
1261 {
1262 count = new_do_write (f, s, do_write);
1263 to_do -= count;
1264 if (count < do_write)
1265 return n - to_do;
1266 }
1267
1268 /* Now write out the remainder. Normally, this will fit in the
1269 buffer, but it's somewhat messier for line-buffered files,
1270 so we let _IO_default_xsputn handle the general case. */
1271 if (to_do)
1272 to_do -= _IO_default_xsputn (f, s+do_write, to_do);
1273 }
1274 return n - to_do;
1275}
1276libc_hidden_ver (_IO_new_file_xsputn, _IO_file_xsputn)
1277
1278size_t
1279_IO_file_xsgetn (FILE *fp, void *data, size_t n)
1280{
1281 size_t want, have;
1282 ssize_t count;
1283 char *s = data;
1284
1285 want = n;
1286
1287 if (fp->_IO_buf_base == NULL)
1288 {
1289 /* Maybe we already have a push back pointer. */
1290 if (fp->_IO_save_base != NULL)
1291 {
1292 free (fp->_IO_save_base);
1293 fp->_flags &= ~_IO_IN_BACKUP;
1294 }
1295 _IO_doallocbuf (fp);
1296 }
1297
1298 while (want > 0)
1299 {
1300 have = fp->_IO_read_end - fp->_IO_read_ptr;
1301 if (want <= have)
1302 {
1303 memcpy (s, fp->_IO_read_ptr, want);
1304 fp->_IO_read_ptr += want;
1305 want = 0;
1306 }
1307 else
1308 {
1309 if (have > 0)
1310 {
1311 s = __mempcpy (s, fp->_IO_read_ptr, have);
1312 want -= have;
1313 fp->_IO_read_ptr += have;
1314 }
1315
1316 /* Check for backup and repeat */
1317 if (_IO_in_backup (fp))
1318 {
1319 _IO_switch_to_main_get_area (fp);
1320 continue;
1321 }
1322
1323 /* If we now want less than a buffer, underflow and repeat
1324 the copy. Otherwise, _IO_SYSREAD directly to
1325 the user buffer. */
1326 if (fp->_IO_buf_base
1327 && want < (size_t) (fp->_IO_buf_end - fp->_IO_buf_base))
1328 {
1329 if (__underflow (fp) == EOF)
1330 break;
1331
1332 continue;
1333 }
1334
1335 /* These must be set before the sysread as we might longjmp out
1336 waiting for input. */
1337 _IO_setg (fp, fp->_IO_buf_base, fp->_IO_buf_base, fp->_IO_buf_base);
1338 _IO_setp (fp, fp->_IO_buf_base, fp->_IO_buf_base);
1339
1340 /* Try to maintain alignment: read a whole number of blocks. */
1341 count = want;
1342 if (fp->_IO_buf_base)
1343 {
1344 size_t block_size = fp->_IO_buf_end - fp->_IO_buf_base;
1345 if (block_size >= 128)
1346 count -= want % block_size;
1347 }
1348
1349 count = _IO_SYSREAD (fp, s, count);
1350 if (count <= 0)
1351 {
1352 if (count == 0)
1353 fp->_flags |= _IO_EOF_SEEN;
1354 else
1355 fp->_flags |= _IO_ERR_SEEN;
1356
1357 break;
1358 }
1359
1360 s += count;
1361 want -= count;
1362 if (fp->_offset != _IO_pos_BAD)
1363 _IO_pos_adjust (fp->_offset, count);
1364 }
1365 }
1366
1367 return n - want;
1368}
1369libc_hidden_def (_IO_file_xsgetn)
1370
1371static size_t
1372_IO_file_xsgetn_mmap (FILE *fp, void *data, size_t n)
1373{
1374 size_t have;
1375 char *read_ptr = fp->_IO_read_ptr;
1376 char *s = (char *) data;
1377
1378 have = fp->_IO_read_end - fp->_IO_read_ptr;
1379
1380 if (have < n)
1381 {
1382 if (__glibc_unlikely (_IO_in_backup (fp)))
1383 {
1384 s = __mempcpy (s, read_ptr, have);
1385 n -= have;
1386 _IO_switch_to_main_get_area (fp);
1387 read_ptr = fp->_IO_read_ptr;
1388 have = fp->_IO_read_end - fp->_IO_read_ptr;
1389 }
1390
1391 if (have < n)
1392 {
1393 /* Check that we are mapping all of the file, in case it grew. */
1394 if (__glibc_unlikely (mmap_remap_check (fp)))
1395 /* We punted mmap, so complete with the vanilla code. */
1396 return s - (char *) data + _IO_XSGETN (fp, data, n);
1397
1398 read_ptr = fp->_IO_read_ptr;
1399 have = fp->_IO_read_end - read_ptr;
1400 }
1401 }
1402
1403 if (have < n)
1404 fp->_flags |= _IO_EOF_SEEN;
1405
1406 if (have != 0)
1407 {
1408 have = MIN (have, n);
1409 s = __mempcpy (s, read_ptr, have);
1410 fp->_IO_read_ptr = read_ptr + have;
1411 }
1412
1413 return s - (char *) data;
1414}
1415
1416static size_t
1417_IO_file_xsgetn_maybe_mmap (FILE *fp, void *data, size_t n)
1418{
1419 /* We only get here if this is the first attempt to read something.
1420 Decide which operations to use and then punt to the chosen one. */
1421
1422 decide_maybe_mmap (fp);
1423 return _IO_XSGETN (fp, data, n);
1424}
1425
1426versioned_symbol (libc, _IO_new_do_write, _IO_do_write, GLIBC_2_1);
1427versioned_symbol (libc, _IO_new_file_attach, _IO_file_attach, GLIBC_2_1);
1428versioned_symbol (libc, _IO_new_file_close_it, _IO_file_close_it, GLIBC_2_1);
1429versioned_symbol (libc, _IO_new_file_finish, _IO_file_finish, GLIBC_2_1);
1430versioned_symbol (libc, _IO_new_file_fopen, _IO_file_fopen, GLIBC_2_1);
1431versioned_symbol (libc, _IO_new_file_init, _IO_file_init, GLIBC_2_1);
1432versioned_symbol (libc, _IO_new_file_setbuf, _IO_file_setbuf, GLIBC_2_1);
1433versioned_symbol (libc, _IO_new_file_sync, _IO_file_sync, GLIBC_2_1);
1434versioned_symbol (libc, _IO_new_file_overflow, _IO_file_overflow, GLIBC_2_1);
1435versioned_symbol (libc, _IO_new_file_seekoff, _IO_file_seekoff, GLIBC_2_1);
1436versioned_symbol (libc, _IO_new_file_underflow, _IO_file_underflow, GLIBC_2_1);
1437versioned_symbol (libc, _IO_new_file_write, _IO_file_write, GLIBC_2_1);
1438versioned_symbol (libc, _IO_new_file_xsputn, _IO_file_xsputn, GLIBC_2_1);
1439
1440const struct _IO_jump_t _IO_file_jumps libio_vtable =
1441{
1442 JUMP_INIT_DUMMY,
1443 JUMP_INIT(finish, _IO_file_finish),
1444 JUMP_INIT(overflow, _IO_file_overflow),
1445 JUMP_INIT(underflow, _IO_file_underflow),
1446 JUMP_INIT(uflow, _IO_default_uflow),
1447 JUMP_INIT(pbackfail, _IO_default_pbackfail),
1448 JUMP_INIT(xsputn, _IO_file_xsputn),
1449 JUMP_INIT(xsgetn, _IO_file_xsgetn),
1450 JUMP_INIT(seekoff, _IO_new_file_seekoff),
1451 JUMP_INIT(seekpos, _IO_default_seekpos),
1452 JUMP_INIT(setbuf, _IO_new_file_setbuf),
1453 JUMP_INIT(sync, _IO_new_file_sync),
1454 JUMP_INIT(doallocate, _IO_file_doallocate),
1455 JUMP_INIT(read, _IO_file_read),
1456 JUMP_INIT(write, _IO_new_file_write),
1457 JUMP_INIT(seek, _IO_file_seek),
1458 JUMP_INIT(close, _IO_file_close),
1459 JUMP_INIT(stat, _IO_file_stat),
1460 JUMP_INIT(showmanyc, _IO_default_showmanyc),
1461 JUMP_INIT(imbue, _IO_default_imbue)
1462};
1463libc_hidden_data_def (_IO_file_jumps)
1464
1465const struct _IO_jump_t _IO_file_jumps_mmap libio_vtable =
1466{
1467 JUMP_INIT_DUMMY,
1468 JUMP_INIT(finish, _IO_file_finish),
1469 JUMP_INIT(overflow, _IO_file_overflow),
1470 JUMP_INIT(underflow, _IO_file_underflow_mmap),
1471 JUMP_INIT(uflow, _IO_default_uflow),
1472 JUMP_INIT(pbackfail, _IO_default_pbackfail),
1473 JUMP_INIT(xsputn, _IO_new_file_xsputn),
1474 JUMP_INIT(xsgetn, _IO_file_xsgetn_mmap),
1475 JUMP_INIT(seekoff, _IO_file_seekoff_mmap),
1476 JUMP_INIT(seekpos, _IO_default_seekpos),
1477 JUMP_INIT(setbuf, (_IO_setbuf_t) _IO_file_setbuf_mmap),
1478 JUMP_INIT(sync, _IO_file_sync_mmap),
1479 JUMP_INIT(doallocate, _IO_file_doallocate),
1480 JUMP_INIT(read, _IO_file_read),
1481 JUMP_INIT(write, _IO_new_file_write),
1482 JUMP_INIT(seek, _IO_file_seek),
1483 JUMP_INIT(close, _IO_file_close_mmap),
1484 JUMP_INIT(stat, _IO_file_stat),
1485 JUMP_INIT(showmanyc, _IO_default_showmanyc),
1486 JUMP_INIT(imbue, _IO_default_imbue)
1487};
1488
1489const struct _IO_jump_t _IO_file_jumps_maybe_mmap libio_vtable =
1490{
1491 JUMP_INIT_DUMMY,
1492 JUMP_INIT(finish, _IO_file_finish),
1493 JUMP_INIT(overflow, _IO_file_overflow),
1494 JUMP_INIT(underflow, _IO_file_underflow_maybe_mmap),
1495 JUMP_INIT(uflow, _IO_default_uflow),
1496 JUMP_INIT(pbackfail, _IO_default_pbackfail),
1497 JUMP_INIT(xsputn, _IO_new_file_xsputn),
1498 JUMP_INIT(xsgetn, _IO_file_xsgetn_maybe_mmap),
1499 JUMP_INIT(seekoff, _IO_file_seekoff_maybe_mmap),
1500 JUMP_INIT(seekpos, _IO_default_seekpos),
1501 JUMP_INIT(setbuf, (_IO_setbuf_t) _IO_file_setbuf_mmap),
1502 JUMP_INIT(sync, _IO_new_file_sync),
1503 JUMP_INIT(doallocate, _IO_file_doallocate),
1504 JUMP_INIT(read, _IO_file_read),
1505 JUMP_INIT(write, _IO_new_file_write),
1506 JUMP_INIT(seek, _IO_file_seek),
1507 JUMP_INIT(close, _IO_file_close),
1508 JUMP_INIT(stat, _IO_file_stat),
1509 JUMP_INIT(showmanyc, _IO_default_showmanyc),
1510 JUMP_INIT(imbue, _IO_default_imbue)
1511};
1512