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 | |
47 | extern 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 | |
105 | void |
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._IO_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. */ |
120 | void |
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 | |
127 | int |
128 | _IO_new_file_close_it (_IO_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 | } |
165 | libc_hidden_ver (_IO_new_file_close_it, _IO_file_close_it) |
166 | |
167 | void |
168 | _IO_new_file_finish (_IO_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 | } |
178 | libc_hidden_ver (_IO_new_file_finish, _IO_file_finish) |
179 | |
180 | _IO_FILE * |
181 | _IO_file_open (_IO_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 | _IO_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 | } |
209 | libc_hidden_def (_IO_file_open) |
210 | |
211 | _IO_FILE * |
212 | _IO_new_file_fopen (_IO_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 | _IO_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 | } |
365 | libc_hidden_ver (_IO_new_file_fopen, _IO_file_fopen) |
366 | |
367 | _IO_FILE * |
368 | _IO_new_file_attach (_IO_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, (_IO_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 | } |
385 | libc_hidden_ver (_IO_new_file_attach, _IO_file_attach) |
386 | |
387 | _IO_FILE * |
388 | _IO_new_file_setbuf (_IO_FILE *fp, char *p, _IO_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 | } |
399 | libc_hidden_ver (_IO_new_file_setbuf, _IO_file_setbuf) |
400 | |
401 | |
402 | _IO_FILE * |
403 | _IO_file_setbuf_mmap (_IO_FILE *fp, char *p, _IO_ssize_t len) |
404 | { |
405 | _IO_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 | |
424 | static _IO_size_t new_do_write (_IO_FILE *, const char *, _IO_size_t); |
425 | |
426 | /* Write TO_DO bytes from DATA to FP. |
427 | Then mark FP as having empty buffers. */ |
428 | |
429 | int |
430 | _IO_new_do_write (_IO_FILE *fp, const char *data, _IO_size_t to_do) |
431 | { |
432 | return (to_do == 0 |
433 | || (_IO_size_t) new_do_write (fp, data, to_do) == to_do) ? 0 : EOF; |
434 | } |
435 | libc_hidden_ver (_IO_new_do_write, _IO_do_write) |
436 | |
437 | static |
438 | _IO_size_t |
439 | new_do_write (_IO_FILE *fp, const char *data, _IO_size_t to_do) |
440 | { |
441 | _IO_size_t count; |
442 | if (fp->_flags & _IO_IS_APPENDING) |
443 | /* On a system without a proper O_APPEND implementation, |
444 | you would need to sys_seek(0, SEEK_END) here, but is |
445 | not needed nor desirable for Unix- or Posix-like systems. |
446 | Instead, just indicate that offset (before and after) is |
447 | unpredictable. */ |
448 | fp->_offset = _IO_pos_BAD; |
449 | else if (fp->_IO_read_end != fp->_IO_write_base) |
450 | { |
451 | _IO_off64_t new_pos |
452 | = _IO_SYSSEEK (fp, fp->_IO_write_base - fp->_IO_read_end, 1); |
453 | if (new_pos == _IO_pos_BAD) |
454 | return 0; |
455 | fp->_offset = new_pos; |
456 | } |
457 | count = _IO_SYSWRITE (fp, data, to_do); |
458 | if (fp->_cur_column && count) |
459 | fp->_cur_column = _IO_adjust_column (fp->_cur_column - 1, data, count) + 1; |
460 | _IO_setg (fp, fp->_IO_buf_base, fp->_IO_buf_base, fp->_IO_buf_base); |
461 | fp->_IO_write_base = fp->_IO_write_ptr = fp->_IO_buf_base; |
462 | fp->_IO_write_end = (fp->_mode <= 0 |
463 | && (fp->_flags & (_IO_LINE_BUF | _IO_UNBUFFERED)) |
464 | ? fp->_IO_buf_base : fp->_IO_buf_end); |
465 | return count; |
466 | } |
467 | |
468 | int |
469 | _IO_new_file_underflow (_IO_FILE *fp) |
470 | { |
471 | _IO_ssize_t count; |
472 | #if 0 |
473 | /* SysV does not make this test; take it out for compatibility */ |
474 | if (fp->_flags & _IO_EOF_SEEN) |
475 | return (EOF); |
476 | #endif |
477 | |
478 | if (fp->_flags & _IO_NO_READS) |
479 | { |
480 | fp->_flags |= _IO_ERR_SEEN; |
481 | __set_errno (EBADF); |
482 | return EOF; |
483 | } |
484 | if (fp->_IO_read_ptr < fp->_IO_read_end) |
485 | return *(unsigned char *) fp->_IO_read_ptr; |
486 | |
487 | if (fp->_IO_buf_base == NULL) |
488 | { |
489 | /* Maybe we already have a push back pointer. */ |
490 | if (fp->_IO_save_base != NULL) |
491 | { |
492 | free (fp->_IO_save_base); |
493 | fp->_flags &= ~_IO_IN_BACKUP; |
494 | } |
495 | _IO_doallocbuf (fp); |
496 | } |
497 | |
498 | /* Flush all line buffered files before reading. */ |
499 | /* FIXME This can/should be moved to genops ?? */ |
500 | if (fp->_flags & (_IO_LINE_BUF|_IO_UNBUFFERED)) |
501 | { |
502 | #if 0 |
503 | _IO_flush_all_linebuffered (); |
504 | #else |
505 | /* We used to flush all line-buffered stream. This really isn't |
506 | required by any standard. My recollection is that |
507 | traditional Unix systems did this for stdout. stderr better |
508 | not be line buffered. So we do just that here |
509 | explicitly. --drepper */ |
510 | _IO_acquire_lock (_IO_stdout); |
511 | |
512 | if ((_IO_stdout->_flags & (_IO_LINKED | _IO_NO_WRITES | _IO_LINE_BUF)) |
513 | == (_IO_LINKED | _IO_LINE_BUF)) |
514 | _IO_OVERFLOW (_IO_stdout, EOF); |
515 | |
516 | _IO_release_lock (_IO_stdout); |
517 | #endif |
518 | } |
519 | |
520 | _IO_switch_to_get_mode (fp); |
521 | |
522 | /* This is very tricky. We have to adjust those |
523 | pointers before we call _IO_SYSREAD () since |
524 | we may longjump () out while waiting for |
525 | input. Those pointers may be screwed up. H.J. */ |
526 | fp->_IO_read_base = fp->_IO_read_ptr = fp->_IO_buf_base; |
527 | fp->_IO_read_end = fp->_IO_buf_base; |
528 | fp->_IO_write_base = fp->_IO_write_ptr = fp->_IO_write_end |
529 | = fp->_IO_buf_base; |
530 | |
531 | count = _IO_SYSREAD (fp, fp->_IO_buf_base, |
532 | fp->_IO_buf_end - fp->_IO_buf_base); |
533 | if (count <= 0) |
534 | { |
535 | if (count == 0) |
536 | fp->_flags |= _IO_EOF_SEEN; |
537 | else |
538 | fp->_flags |= _IO_ERR_SEEN, count = 0; |
539 | } |
540 | fp->_IO_read_end += count; |
541 | if (count == 0) |
542 | { |
543 | /* If a stream is read to EOF, the calling application may switch active |
544 | handles. As a result, our offset cache would no longer be valid, so |
545 | unset it. */ |
546 | fp->_offset = _IO_pos_BAD; |
547 | return EOF; |
548 | } |
549 | if (fp->_offset != _IO_pos_BAD) |
550 | _IO_pos_adjust (fp->_offset, count); |
551 | return *(unsigned char *) fp->_IO_read_ptr; |
552 | } |
553 | libc_hidden_ver (_IO_new_file_underflow, _IO_file_underflow) |
554 | |
555 | /* Guts of underflow callback if we mmap the file. This stats the file and |
556 | updates the stream state to match. In the normal case we return zero. |
557 | If the file is no longer eligible for mmap, its jump tables are reset to |
558 | the vanilla ones and we return nonzero. */ |
559 | static int |
560 | mmap_remap_check (_IO_FILE *fp) |
561 | { |
562 | struct stat64 st; |
563 | |
564 | if (_IO_SYSSTAT (fp, &st) == 0 |
565 | && S_ISREG (st.st_mode) && st.st_size != 0 |
566 | /* Limit the file size to 1MB for 32-bit machines. */ |
567 | && (sizeof (ptrdiff_t) > 4 || st.st_size < 1*1024*1024)) |
568 | { |
569 | const size_t pagesize = __getpagesize (); |
570 | # define ROUNDED(x) (((x) + pagesize - 1) & ~(pagesize - 1)) |
571 | if (ROUNDED (st.st_size) < ROUNDED (fp->_IO_buf_end |
572 | - fp->_IO_buf_base)) |
573 | { |
574 | /* We can trim off some pages past the end of the file. */ |
575 | (void) __munmap (fp->_IO_buf_base + ROUNDED (st.st_size), |
576 | ROUNDED (fp->_IO_buf_end - fp->_IO_buf_base) |
577 | - ROUNDED (st.st_size)); |
578 | fp->_IO_buf_end = fp->_IO_buf_base + st.st_size; |
579 | } |
580 | else if (ROUNDED (st.st_size) > ROUNDED (fp->_IO_buf_end |
581 | - fp->_IO_buf_base)) |
582 | { |
583 | /* The file added some pages. We need to remap it. */ |
584 | void *p; |
585 | #ifdef _G_HAVE_MREMAP |
586 | p = __mremap (fp->_IO_buf_base, ROUNDED (fp->_IO_buf_end |
587 | - fp->_IO_buf_base), |
588 | ROUNDED (st.st_size), MREMAP_MAYMOVE); |
589 | if (p == MAP_FAILED) |
590 | { |
591 | (void) __munmap (fp->_IO_buf_base, |
592 | fp->_IO_buf_end - fp->_IO_buf_base); |
593 | goto punt; |
594 | } |
595 | #else |
596 | (void) __munmap (fp->_IO_buf_base, |
597 | fp->_IO_buf_end - fp->_IO_buf_base); |
598 | p = __mmap64 (NULL, st.st_size, PROT_READ, MAP_SHARED, |
599 | fp->_fileno, 0); |
600 | if (p == MAP_FAILED) |
601 | goto punt; |
602 | #endif |
603 | fp->_IO_buf_base = p; |
604 | fp->_IO_buf_end = fp->_IO_buf_base + st.st_size; |
605 | } |
606 | else |
607 | { |
608 | /* The number of pages didn't change. */ |
609 | fp->_IO_buf_end = fp->_IO_buf_base + st.st_size; |
610 | } |
611 | # undef ROUNDED |
612 | |
613 | fp->_offset -= fp->_IO_read_end - fp->_IO_read_ptr; |
614 | _IO_setg (fp, fp->_IO_buf_base, |
615 | fp->_offset < fp->_IO_buf_end - fp->_IO_buf_base |
616 | ? fp->_IO_buf_base + fp->_offset : fp->_IO_buf_end, |
617 | fp->_IO_buf_end); |
618 | |
619 | /* If we are already positioned at or past the end of the file, don't |
620 | change the current offset. If not, seek past what we have mapped, |
621 | mimicking the position left by a normal underflow reading into its |
622 | buffer until EOF. */ |
623 | |
624 | if (fp->_offset < fp->_IO_buf_end - fp->_IO_buf_base) |
625 | { |
626 | if (__lseek64 (fp->_fileno, fp->_IO_buf_end - fp->_IO_buf_base, |
627 | SEEK_SET) |
628 | != fp->_IO_buf_end - fp->_IO_buf_base) |
629 | fp->_flags |= _IO_ERR_SEEN; |
630 | else |
631 | fp->_offset = fp->_IO_buf_end - fp->_IO_buf_base; |
632 | } |
633 | |
634 | return 0; |
635 | } |
636 | else |
637 | { |
638 | /* Life is no longer good for mmap. Punt it. */ |
639 | (void) __munmap (fp->_IO_buf_base, |
640 | fp->_IO_buf_end - fp->_IO_buf_base); |
641 | punt: |
642 | fp->_IO_buf_base = fp->_IO_buf_end = NULL; |
643 | _IO_setg (fp, NULL, NULL, NULL); |
644 | if (fp->_mode <= 0) |
645 | _IO_JUMPS_FILE_plus (fp) = &_IO_file_jumps; |
646 | else |
647 | _IO_JUMPS_FILE_plus (fp) = &_IO_wfile_jumps; |
648 | fp->_wide_data->_wide_vtable = &_IO_wfile_jumps; |
649 | |
650 | return 1; |
651 | } |
652 | } |
653 | |
654 | /* Special callback replacing the underflow callbacks if we mmap the file. */ |
655 | int |
656 | _IO_file_underflow_mmap (_IO_FILE *fp) |
657 | { |
658 | if (fp->_IO_read_ptr < fp->_IO_read_end) |
659 | return *(unsigned char *) fp->_IO_read_ptr; |
660 | |
661 | if (__glibc_unlikely (mmap_remap_check (fp))) |
662 | /* We punted to the regular file functions. */ |
663 | return _IO_UNDERFLOW (fp); |
664 | |
665 | if (fp->_IO_read_ptr < fp->_IO_read_end) |
666 | return *(unsigned char *) fp->_IO_read_ptr; |
667 | |
668 | fp->_flags |= _IO_EOF_SEEN; |
669 | return EOF; |
670 | } |
671 | |
672 | static void |
673 | decide_maybe_mmap (_IO_FILE *fp) |
674 | { |
675 | /* We use the file in read-only mode. This could mean we can |
676 | mmap the file and use it without any copying. But not all |
677 | file descriptors are for mmap-able objects and on 32-bit |
678 | machines we don't want to map files which are too large since |
679 | this would require too much virtual memory. */ |
680 | struct stat64 st; |
681 | |
682 | if (_IO_SYSSTAT (fp, &st) == 0 |
683 | && S_ISREG (st.st_mode) && st.st_size != 0 |
684 | /* Limit the file size to 1MB for 32-bit machines. */ |
685 | && (sizeof (ptrdiff_t) > 4 || st.st_size < 1*1024*1024) |
686 | /* Sanity check. */ |
687 | && (fp->_offset == _IO_pos_BAD || fp->_offset <= st.st_size)) |
688 | { |
689 | /* Try to map the file. */ |
690 | void *p; |
691 | |
692 | p = __mmap64 (NULL, st.st_size, PROT_READ, MAP_SHARED, fp->_fileno, 0); |
693 | if (p != MAP_FAILED) |
694 | { |
695 | /* OK, we managed to map the file. Set the buffer up and use a |
696 | special jump table with simplified underflow functions which |
697 | never tries to read anything from the file. */ |
698 | |
699 | if (__lseek64 (fp->_fileno, st.st_size, SEEK_SET) != st.st_size) |
700 | { |
701 | (void) __munmap (p, st.st_size); |
702 | fp->_offset = _IO_pos_BAD; |
703 | } |
704 | else |
705 | { |
706 | _IO_setb (fp, p, (char *) p + st.st_size, 0); |
707 | |
708 | if (fp->_offset == _IO_pos_BAD) |
709 | fp->_offset = 0; |
710 | |
711 | _IO_setg (fp, p, p + fp->_offset, p + st.st_size); |
712 | fp->_offset = st.st_size; |
713 | |
714 | if (fp->_mode <= 0) |
715 | _IO_JUMPS_FILE_plus (fp) = &_IO_file_jumps_mmap; |
716 | else |
717 | _IO_JUMPS_FILE_plus (fp) = &_IO_wfile_jumps_mmap; |
718 | fp->_wide_data->_wide_vtable = &_IO_wfile_jumps_mmap; |
719 | |
720 | return; |
721 | } |
722 | } |
723 | } |
724 | |
725 | /* We couldn't use mmap, so revert to the vanilla file operations. */ |
726 | |
727 | if (fp->_mode <= 0) |
728 | _IO_JUMPS_FILE_plus (fp) = &_IO_file_jumps; |
729 | else |
730 | _IO_JUMPS_FILE_plus (fp) = &_IO_wfile_jumps; |
731 | fp->_wide_data->_wide_vtable = &_IO_wfile_jumps; |
732 | } |
733 | |
734 | int |
735 | _IO_file_underflow_maybe_mmap (_IO_FILE *fp) |
736 | { |
737 | /* This is the first read attempt. Choose mmap or vanilla operations |
738 | and then punt to the chosen underflow routine. */ |
739 | decide_maybe_mmap (fp); |
740 | return _IO_UNDERFLOW (fp); |
741 | } |
742 | |
743 | |
744 | int |
745 | _IO_new_file_overflow (_IO_FILE *f, int ch) |
746 | { |
747 | if (f->_flags & _IO_NO_WRITES) /* SET ERROR */ |
748 | { |
749 | f->_flags |= _IO_ERR_SEEN; |
750 | __set_errno (EBADF); |
751 | return EOF; |
752 | } |
753 | /* If currently reading or no buffer allocated. */ |
754 | if ((f->_flags & _IO_CURRENTLY_PUTTING) == 0 || f->_IO_write_base == NULL) |
755 | { |
756 | /* Allocate a buffer if needed. */ |
757 | if (f->_IO_write_base == NULL) |
758 | { |
759 | _IO_doallocbuf (f); |
760 | _IO_setg (f, f->_IO_buf_base, f->_IO_buf_base, f->_IO_buf_base); |
761 | } |
762 | /* Otherwise must be currently reading. |
763 | If _IO_read_ptr (and hence also _IO_read_end) is at the buffer end, |
764 | logically slide the buffer forwards one block (by setting the |
765 | read pointers to all point at the beginning of the block). This |
766 | makes room for subsequent output. |
767 | Otherwise, set the read pointers to _IO_read_end (leaving that |
768 | alone, so it can continue to correspond to the external position). */ |
769 | if (__glibc_unlikely (_IO_in_backup (f))) |
770 | { |
771 | size_t nbackup = f->_IO_read_end - f->_IO_read_ptr; |
772 | _IO_free_backup_area (f); |
773 | f->_IO_read_base -= MIN (nbackup, |
774 | f->_IO_read_base - f->_IO_buf_base); |
775 | f->_IO_read_ptr = f->_IO_read_base; |
776 | } |
777 | |
778 | if (f->_IO_read_ptr == f->_IO_buf_end) |
779 | f->_IO_read_end = f->_IO_read_ptr = f->_IO_buf_base; |
780 | f->_IO_write_ptr = f->_IO_read_ptr; |
781 | f->_IO_write_base = f->_IO_write_ptr; |
782 | f->_IO_write_end = f->_IO_buf_end; |
783 | f->_IO_read_base = f->_IO_read_ptr = f->_IO_read_end; |
784 | |
785 | f->_flags |= _IO_CURRENTLY_PUTTING; |
786 | if (f->_mode <= 0 && f->_flags & (_IO_LINE_BUF | _IO_UNBUFFERED)) |
787 | f->_IO_write_end = f->_IO_write_ptr; |
788 | } |
789 | if (ch == EOF) |
790 | return _IO_do_write (f, f->_IO_write_base, |
791 | f->_IO_write_ptr - f->_IO_write_base); |
792 | if (f->_IO_write_ptr == f->_IO_buf_end ) /* Buffer is really full */ |
793 | if (_IO_do_flush (f) == EOF) |
794 | return EOF; |
795 | *f->_IO_write_ptr++ = ch; |
796 | if ((f->_flags & _IO_UNBUFFERED) |
797 | || ((f->_flags & _IO_LINE_BUF) && ch == '\n')) |
798 | if (_IO_do_write (f, f->_IO_write_base, |
799 | f->_IO_write_ptr - f->_IO_write_base) == EOF) |
800 | return EOF; |
801 | return (unsigned char) ch; |
802 | } |
803 | libc_hidden_ver (_IO_new_file_overflow, _IO_file_overflow) |
804 | |
805 | int |
806 | _IO_new_file_sync (_IO_FILE *fp) |
807 | { |
808 | _IO_ssize_t delta; |
809 | int retval = 0; |
810 | |
811 | /* char* ptr = cur_ptr(); */ |
812 | if (fp->_IO_write_ptr > fp->_IO_write_base) |
813 | if (_IO_do_flush(fp)) return EOF; |
814 | delta = fp->_IO_read_ptr - fp->_IO_read_end; |
815 | if (delta != 0) |
816 | { |
817 | #ifdef TODO |
818 | if (_IO_in_backup (fp)) |
819 | delta -= eGptr () - Gbase (); |
820 | #endif |
821 | _IO_off64_t new_pos = _IO_SYSSEEK (fp, delta, 1); |
822 | if (new_pos != (_IO_off64_t) EOF) |
823 | fp->_IO_read_end = fp->_IO_read_ptr; |
824 | else if (errno == ESPIPE) |
825 | ; /* Ignore error from unseekable devices. */ |
826 | else |
827 | retval = EOF; |
828 | } |
829 | if (retval != EOF) |
830 | fp->_offset = _IO_pos_BAD; |
831 | /* FIXME: Cleanup - can this be shared? */ |
832 | /* setg(base(), ptr, ptr); */ |
833 | return retval; |
834 | } |
835 | libc_hidden_ver (_IO_new_file_sync, _IO_file_sync) |
836 | |
837 | static int |
838 | _IO_file_sync_mmap (_IO_FILE *fp) |
839 | { |
840 | if (fp->_IO_read_ptr != fp->_IO_read_end) |
841 | { |
842 | #ifdef TODO |
843 | if (_IO_in_backup (fp)) |
844 | delta -= eGptr () - Gbase (); |
845 | #endif |
846 | if (__lseek64 (fp->_fileno, fp->_IO_read_ptr - fp->_IO_buf_base, |
847 | SEEK_SET) |
848 | != fp->_IO_read_ptr - fp->_IO_buf_base) |
849 | { |
850 | fp->_flags |= _IO_ERR_SEEN; |
851 | return EOF; |
852 | } |
853 | } |
854 | fp->_offset = fp->_IO_read_ptr - fp->_IO_buf_base; |
855 | fp->_IO_read_end = fp->_IO_read_ptr = fp->_IO_read_base; |
856 | return 0; |
857 | } |
858 | |
859 | /* ftell{,o} implementation. The only time we modify the state of the stream |
860 | is when we have unflushed writes. In that case we seek to the end and |
861 | record that offset in the stream object. */ |
862 | static _IO_off64_t |
863 | do_ftell (_IO_FILE *fp) |
864 | { |
865 | _IO_off64_t result, offset = 0; |
866 | |
867 | /* No point looking at unflushed data if we haven't allocated buffers |
868 | yet. */ |
869 | if (fp->_IO_buf_base != NULL) |
870 | { |
871 | bool unflushed_writes = fp->_IO_write_ptr > fp->_IO_write_base; |
872 | |
873 | bool append_mode = (fp->_flags & _IO_IS_APPENDING) == _IO_IS_APPENDING; |
874 | |
875 | /* When we have unflushed writes in append mode, seek to the end of the |
876 | file and record that offset. This is the only time we change the file |
877 | stream state and it is safe since the file handle is active. */ |
878 | if (unflushed_writes && append_mode) |
879 | { |
880 | result = _IO_SYSSEEK (fp, 0, _IO_seek_end); |
881 | if (result == _IO_pos_BAD) |
882 | return EOF; |
883 | else |
884 | fp->_offset = result; |
885 | } |
886 | |
887 | /* Adjust for unflushed data. */ |
888 | if (!unflushed_writes) |
889 | offset -= fp->_IO_read_end - fp->_IO_read_ptr; |
890 | /* We don't trust _IO_read_end to represent the current file offset when |
891 | writing in append mode because the value would have to be shifted to |
892 | the end of the file during a flush. Use the write base instead, along |
893 | with the new offset we got above when we did a seek to the end of the |
894 | file. */ |
895 | else if (append_mode) |
896 | offset += fp->_IO_write_ptr - fp->_IO_write_base; |
897 | /* For all other modes, _IO_read_end represents the file offset. */ |
898 | else |
899 | offset += fp->_IO_write_ptr - fp->_IO_read_end; |
900 | } |
901 | |
902 | if (fp->_offset != _IO_pos_BAD) |
903 | result = fp->_offset; |
904 | else |
905 | result = _IO_SYSSEEK (fp, 0, _IO_seek_cur); |
906 | |
907 | if (result == EOF) |
908 | return result; |
909 | |
910 | result += offset; |
911 | |
912 | if (result < 0) |
913 | { |
914 | __set_errno (EINVAL); |
915 | return EOF; |
916 | } |
917 | |
918 | return result; |
919 | } |
920 | |
921 | _IO_off64_t |
922 | _IO_new_file_seekoff (_IO_FILE *fp, _IO_off64_t offset, int dir, int mode) |
923 | { |
924 | _IO_off64_t result; |
925 | _IO_off64_t delta, new_offset; |
926 | long count; |
927 | |
928 | /* Short-circuit into a separate function. We don't want to mix any |
929 | functionality and we don't want to touch anything inside the FILE |
930 | object. */ |
931 | if (mode == 0) |
932 | return do_ftell (fp); |
933 | |
934 | /* POSIX.1 8.2.3.7 says that after a call the fflush() the file |
935 | offset of the underlying file must be exact. */ |
936 | int must_be_exact = (fp->_IO_read_base == fp->_IO_read_end |
937 | && fp->_IO_write_base == fp->_IO_write_ptr); |
938 | |
939 | bool was_writing = (fp->_IO_write_ptr > fp->_IO_write_base |
940 | || _IO_in_put_mode (fp)); |
941 | |
942 | /* Flush unwritten characters. |
943 | (This may do an unneeded write if we seek within the buffer. |
944 | But to be able to switch to reading, we would need to set |
945 | egptr to pptr. That can't be done in the current design, |
946 | which assumes file_ptr() is eGptr. Anyway, since we probably |
947 | end up flushing when we close(), it doesn't make much difference.) |
948 | FIXME: simulate mem-mapped files. */ |
949 | if (was_writing && _IO_switch_to_get_mode (fp)) |
950 | return EOF; |
951 | |
952 | if (fp->_IO_buf_base == NULL) |
953 | { |
954 | /* It could be that we already have a pushback buffer. */ |
955 | if (fp->_IO_read_base != NULL) |
956 | { |
957 | free (fp->_IO_read_base); |
958 | fp->_flags &= ~_IO_IN_BACKUP; |
959 | } |
960 | _IO_doallocbuf (fp); |
961 | _IO_setp (fp, fp->_IO_buf_base, fp->_IO_buf_base); |
962 | _IO_setg (fp, fp->_IO_buf_base, fp->_IO_buf_base, fp->_IO_buf_base); |
963 | } |
964 | |
965 | switch (dir) |
966 | { |
967 | case _IO_seek_cur: |
968 | /* Adjust for read-ahead (bytes is buffer). */ |
969 | offset -= fp->_IO_read_end - fp->_IO_read_ptr; |
970 | |
971 | if (fp->_offset == _IO_pos_BAD) |
972 | goto dumb; |
973 | /* Make offset absolute, assuming current pointer is file_ptr(). */ |
974 | offset += fp->_offset; |
975 | if (offset < 0) |
976 | { |
977 | __set_errno (EINVAL); |
978 | return EOF; |
979 | } |
980 | |
981 | dir = _IO_seek_set; |
982 | break; |
983 | case _IO_seek_set: |
984 | break; |
985 | case _IO_seek_end: |
986 | { |
987 | struct stat64 st; |
988 | if (_IO_SYSSTAT (fp, &st) == 0 && S_ISREG (st.st_mode)) |
989 | { |
990 | offset += st.st_size; |
991 | dir = _IO_seek_set; |
992 | } |
993 | else |
994 | goto dumb; |
995 | } |
996 | } |
997 | |
998 | _IO_free_backup_area (fp); |
999 | |
1000 | /* At this point, dir==_IO_seek_set. */ |
1001 | |
1002 | /* If destination is within current buffer, optimize: */ |
1003 | if (fp->_offset != _IO_pos_BAD && fp->_IO_read_base != NULL |
1004 | && !_IO_in_backup (fp)) |
1005 | { |
1006 | _IO_off64_t start_offset = (fp->_offset |
1007 | - (fp->_IO_read_end - fp->_IO_buf_base)); |
1008 | if (offset >= start_offset && offset < fp->_offset) |
1009 | { |
1010 | _IO_setg (fp, fp->_IO_buf_base, |
1011 | fp->_IO_buf_base + (offset - start_offset), |
1012 | fp->_IO_read_end); |
1013 | _IO_setp (fp, fp->_IO_buf_base, fp->_IO_buf_base); |
1014 | |
1015 | _IO_mask_flags (fp, 0, _IO_EOF_SEEN); |
1016 | goto resync; |
1017 | } |
1018 | } |
1019 | |
1020 | if (fp->_flags & _IO_NO_READS) |
1021 | goto dumb; |
1022 | |
1023 | /* Try to seek to a block boundary, to improve kernel page management. */ |
1024 | new_offset = offset & ~(fp->_IO_buf_end - fp->_IO_buf_base - 1); |
1025 | delta = offset - new_offset; |
1026 | if (delta > fp->_IO_buf_end - fp->_IO_buf_base) |
1027 | { |
1028 | new_offset = offset; |
1029 | delta = 0; |
1030 | } |
1031 | result = _IO_SYSSEEK (fp, new_offset, 0); |
1032 | if (result < 0) |
1033 | return EOF; |
1034 | if (delta == 0) |
1035 | count = 0; |
1036 | else |
1037 | { |
1038 | count = _IO_SYSREAD (fp, fp->_IO_buf_base, |
1039 | (must_be_exact |
1040 | ? delta : fp->_IO_buf_end - fp->_IO_buf_base)); |
1041 | if (count < delta) |
1042 | { |
1043 | /* We weren't allowed to read, but try to seek the remainder. */ |
1044 | offset = count == EOF ? delta : delta-count; |
1045 | dir = _IO_seek_cur; |
1046 | goto dumb; |
1047 | } |
1048 | } |
1049 | _IO_setg (fp, fp->_IO_buf_base, fp->_IO_buf_base + delta, |
1050 | fp->_IO_buf_base + count); |
1051 | _IO_setp (fp, fp->_IO_buf_base, fp->_IO_buf_base); |
1052 | fp->_offset = result + count; |
1053 | _IO_mask_flags (fp, 0, _IO_EOF_SEEN); |
1054 | return offset; |
1055 | dumb: |
1056 | |
1057 | _IO_unsave_markers (fp); |
1058 | result = _IO_SYSSEEK (fp, offset, dir); |
1059 | if (result != EOF) |
1060 | { |
1061 | _IO_mask_flags (fp, 0, _IO_EOF_SEEN); |
1062 | fp->_offset = result; |
1063 | _IO_setg (fp, fp->_IO_buf_base, fp->_IO_buf_base, fp->_IO_buf_base); |
1064 | _IO_setp (fp, fp->_IO_buf_base, fp->_IO_buf_base); |
1065 | } |
1066 | return result; |
1067 | |
1068 | resync: |
1069 | /* We need to do it since it is possible that the file offset in |
1070 | the kernel may be changed behind our back. It may happen when |
1071 | we fopen a file and then do a fork. One process may access the |
1072 | file and the kernel file offset will be changed. */ |
1073 | if (fp->_offset >= 0) |
1074 | _IO_SYSSEEK (fp, fp->_offset, 0); |
1075 | |
1076 | return offset; |
1077 | } |
1078 | libc_hidden_ver (_IO_new_file_seekoff, _IO_file_seekoff) |
1079 | |
1080 | _IO_off64_t |
1081 | _IO_file_seekoff_mmap (_IO_FILE *fp, _IO_off64_t offset, int dir, int mode) |
1082 | { |
1083 | _IO_off64_t result; |
1084 | |
1085 | /* If we are only interested in the current position, calculate it and |
1086 | return right now. This calculation does the right thing when we are |
1087 | using a pushback buffer, but in the usual case has the same value as |
1088 | (fp->_IO_read_ptr - fp->_IO_buf_base). */ |
1089 | if (mode == 0) |
1090 | return fp->_offset - (fp->_IO_read_end - fp->_IO_read_ptr); |
1091 | |
1092 | switch (dir) |
1093 | { |
1094 | case _IO_seek_cur: |
1095 | /* Adjust for read-ahead (bytes is buffer). */ |
1096 | offset += fp->_IO_read_ptr - fp->_IO_read_base; |
1097 | break; |
1098 | case _IO_seek_set: |
1099 | break; |
1100 | case _IO_seek_end: |
1101 | offset += fp->_IO_buf_end - fp->_IO_buf_base; |
1102 | break; |
1103 | } |
1104 | /* At this point, dir==_IO_seek_set. */ |
1105 | |
1106 | if (offset < 0) |
1107 | { |
1108 | /* No negative offsets are valid. */ |
1109 | __set_errno (EINVAL); |
1110 | return EOF; |
1111 | } |
1112 | |
1113 | result = _IO_SYSSEEK (fp, offset, 0); |
1114 | if (result < 0) |
1115 | return EOF; |
1116 | |
1117 | if (offset > fp->_IO_buf_end - fp->_IO_buf_base) |
1118 | /* One can fseek arbitrarily past the end of the file |
1119 | and it is meaningless until one attempts to read. |
1120 | Leave the buffer pointers in EOF state until underflow. */ |
1121 | _IO_setg (fp, fp->_IO_buf_base, fp->_IO_buf_end, fp->_IO_buf_end); |
1122 | else |
1123 | /* Adjust the read pointers to match the file position, |
1124 | but so the next read attempt will call underflow. */ |
1125 | _IO_setg (fp, fp->_IO_buf_base, fp->_IO_buf_base + offset, |
1126 | fp->_IO_buf_base + offset); |
1127 | |
1128 | fp->_offset = result; |
1129 | |
1130 | _IO_mask_flags (fp, 0, _IO_EOF_SEEN); |
1131 | |
1132 | return offset; |
1133 | } |
1134 | |
1135 | static _IO_off64_t |
1136 | _IO_file_seekoff_maybe_mmap (_IO_FILE *fp, _IO_off64_t offset, int dir, |
1137 | int mode) |
1138 | { |
1139 | /* We only get here when we haven't tried to read anything yet. |
1140 | So there is nothing more useful for us to do here than just |
1141 | the underlying lseek call. */ |
1142 | |
1143 | _IO_off64_t result = _IO_SYSSEEK (fp, offset, dir); |
1144 | if (result < 0) |
1145 | return EOF; |
1146 | |
1147 | fp->_offset = result; |
1148 | return result; |
1149 | } |
1150 | |
1151 | _IO_ssize_t |
1152 | _IO_file_read (_IO_FILE *fp, void *buf, _IO_ssize_t size) |
1153 | { |
1154 | return (__builtin_expect (fp->_flags2 & _IO_FLAGS2_NOTCANCEL, 0) |
1155 | ? __read_nocancel (fp->_fileno, buf, size) |
1156 | : __read (fp->_fileno, buf, size)); |
1157 | } |
1158 | libc_hidden_def (_IO_file_read) |
1159 | |
1160 | _IO_off64_t |
1161 | _IO_file_seek (_IO_FILE *fp, _IO_off64_t offset, int dir) |
1162 | { |
1163 | return __lseek64 (fp->_fileno, offset, dir); |
1164 | } |
1165 | libc_hidden_def (_IO_file_seek) |
1166 | |
1167 | int |
1168 | _IO_file_stat (_IO_FILE *fp, void *st) |
1169 | { |
1170 | return __fxstat64 (_STAT_VER, fp->_fileno, (struct stat64 *) st); |
1171 | } |
1172 | libc_hidden_def (_IO_file_stat) |
1173 | |
1174 | int |
1175 | _IO_file_close_mmap (_IO_FILE *fp) |
1176 | { |
1177 | /* In addition to closing the file descriptor we have to unmap the file. */ |
1178 | (void) __munmap (fp->_IO_buf_base, fp->_IO_buf_end - fp->_IO_buf_base); |
1179 | fp->_IO_buf_base = fp->_IO_buf_end = NULL; |
1180 | /* Cancelling close should be avoided if possible since it leaves an |
1181 | unrecoverable state behind. */ |
1182 | return __close_nocancel (fp->_fileno); |
1183 | } |
1184 | |
1185 | int |
1186 | _IO_file_close (_IO_FILE *fp) |
1187 | { |
1188 | /* Cancelling close should be avoided if possible since it leaves an |
1189 | unrecoverable state behind. */ |
1190 | return __close_nocancel (fp->_fileno); |
1191 | } |
1192 | libc_hidden_def (_IO_file_close) |
1193 | |
1194 | _IO_ssize_t |
1195 | _IO_new_file_write (_IO_FILE *f, const void *data, _IO_ssize_t n) |
1196 | { |
1197 | _IO_ssize_t to_do = n; |
1198 | while (to_do > 0) |
1199 | { |
1200 | _IO_ssize_t count = (__builtin_expect (f->_flags2 |
1201 | & _IO_FLAGS2_NOTCANCEL, 0) |
1202 | ? __write_nocancel (f->_fileno, data, to_do) |
1203 | : __write (f->_fileno, data, to_do)); |
1204 | if (count < 0) |
1205 | { |
1206 | f->_flags |= _IO_ERR_SEEN; |
1207 | break; |
1208 | } |
1209 | to_do -= count; |
1210 | data = (void *) ((char *) data + count); |
1211 | } |
1212 | n -= to_do; |
1213 | if (f->_offset >= 0) |
1214 | f->_offset += n; |
1215 | return n; |
1216 | } |
1217 | |
1218 | _IO_size_t |
1219 | _IO_new_file_xsputn (_IO_FILE *f, const void *data, _IO_size_t n) |
1220 | { |
1221 | const char *s = (const char *) data; |
1222 | _IO_size_t to_do = n; |
1223 | int must_flush = 0; |
1224 | _IO_size_t count = 0; |
1225 | |
1226 | if (n <= 0) |
1227 | return 0; |
1228 | /* This is an optimized implementation. |
1229 | If the amount to be written straddles a block boundary |
1230 | (or the filebuf is unbuffered), use sys_write directly. */ |
1231 | |
1232 | /* First figure out how much space is available in the buffer. */ |
1233 | if ((f->_flags & _IO_LINE_BUF) && (f->_flags & _IO_CURRENTLY_PUTTING)) |
1234 | { |
1235 | count = f->_IO_buf_end - f->_IO_write_ptr; |
1236 | if (count >= n) |
1237 | { |
1238 | const char *p; |
1239 | for (p = s + n; p > s; ) |
1240 | { |
1241 | if (*--p == '\n') |
1242 | { |
1243 | count = p - s + 1; |
1244 | must_flush = 1; |
1245 | break; |
1246 | } |
1247 | } |
1248 | } |
1249 | } |
1250 | else if (f->_IO_write_end > f->_IO_write_ptr) |
1251 | count = f->_IO_write_end - f->_IO_write_ptr; /* Space available. */ |
1252 | |
1253 | /* Then fill the buffer. */ |
1254 | if (count > 0) |
1255 | { |
1256 | if (count > to_do) |
1257 | count = to_do; |
1258 | f->_IO_write_ptr = __mempcpy (f->_IO_write_ptr, s, count); |
1259 | s += count; |
1260 | to_do -= count; |
1261 | } |
1262 | if (to_do + must_flush > 0) |
1263 | { |
1264 | _IO_size_t block_size, do_write; |
1265 | /* Next flush the (full) buffer. */ |
1266 | if (_IO_OVERFLOW (f, EOF) == EOF) |
1267 | /* If nothing else has to be written we must not signal the |
1268 | caller that everything has been written. */ |
1269 | return to_do == 0 ? EOF : n - to_do; |
1270 | |
1271 | /* Try to maintain alignment: write a whole number of blocks. */ |
1272 | block_size = f->_IO_buf_end - f->_IO_buf_base; |
1273 | do_write = to_do - (block_size >= 128 ? to_do % block_size : 0); |
1274 | |
1275 | if (do_write) |
1276 | { |
1277 | count = new_do_write (f, s, do_write); |
1278 | to_do -= count; |
1279 | if (count < do_write) |
1280 | return n - to_do; |
1281 | } |
1282 | |
1283 | /* Now write out the remainder. Normally, this will fit in the |
1284 | buffer, but it's somewhat messier for line-buffered files, |
1285 | so we let _IO_default_xsputn handle the general case. */ |
1286 | if (to_do) |
1287 | to_do -= _IO_default_xsputn (f, s+do_write, to_do); |
1288 | } |
1289 | return n - to_do; |
1290 | } |
1291 | libc_hidden_ver (_IO_new_file_xsputn, _IO_file_xsputn) |
1292 | |
1293 | _IO_size_t |
1294 | _IO_file_xsgetn (_IO_FILE *fp, void *data, _IO_size_t n) |
1295 | { |
1296 | _IO_size_t want, have; |
1297 | _IO_ssize_t count; |
1298 | char *s = data; |
1299 | |
1300 | want = n; |
1301 | |
1302 | if (fp->_IO_buf_base == NULL) |
1303 | { |
1304 | /* Maybe we already have a push back pointer. */ |
1305 | if (fp->_IO_save_base != NULL) |
1306 | { |
1307 | free (fp->_IO_save_base); |
1308 | fp->_flags &= ~_IO_IN_BACKUP; |
1309 | } |
1310 | _IO_doallocbuf (fp); |
1311 | } |
1312 | |
1313 | while (want > 0) |
1314 | { |
1315 | have = fp->_IO_read_end - fp->_IO_read_ptr; |
1316 | if (want <= have) |
1317 | { |
1318 | memcpy (s, fp->_IO_read_ptr, want); |
1319 | fp->_IO_read_ptr += want; |
1320 | want = 0; |
1321 | } |
1322 | else |
1323 | { |
1324 | if (have > 0) |
1325 | { |
1326 | s = __mempcpy (s, fp->_IO_read_ptr, have); |
1327 | want -= have; |
1328 | fp->_IO_read_ptr += have; |
1329 | } |
1330 | |
1331 | /* Check for backup and repeat */ |
1332 | if (_IO_in_backup (fp)) |
1333 | { |
1334 | _IO_switch_to_main_get_area (fp); |
1335 | continue; |
1336 | } |
1337 | |
1338 | /* If we now want less than a buffer, underflow and repeat |
1339 | the copy. Otherwise, _IO_SYSREAD directly to |
1340 | the user buffer. */ |
1341 | if (fp->_IO_buf_base |
1342 | && want < (size_t) (fp->_IO_buf_end - fp->_IO_buf_base)) |
1343 | { |
1344 | if (__underflow (fp) == EOF) |
1345 | break; |
1346 | |
1347 | continue; |
1348 | } |
1349 | |
1350 | /* These must be set before the sysread as we might longjmp out |
1351 | waiting for input. */ |
1352 | _IO_setg (fp, fp->_IO_buf_base, fp->_IO_buf_base, fp->_IO_buf_base); |
1353 | _IO_setp (fp, fp->_IO_buf_base, fp->_IO_buf_base); |
1354 | |
1355 | /* Try to maintain alignment: read a whole number of blocks. */ |
1356 | count = want; |
1357 | if (fp->_IO_buf_base) |
1358 | { |
1359 | _IO_size_t block_size = fp->_IO_buf_end - fp->_IO_buf_base; |
1360 | if (block_size >= 128) |
1361 | count -= want % block_size; |
1362 | } |
1363 | |
1364 | count = _IO_SYSREAD (fp, s, count); |
1365 | if (count <= 0) |
1366 | { |
1367 | if (count == 0) |
1368 | fp->_flags |= _IO_EOF_SEEN; |
1369 | else |
1370 | fp->_flags |= _IO_ERR_SEEN; |
1371 | |
1372 | break; |
1373 | } |
1374 | |
1375 | s += count; |
1376 | want -= count; |
1377 | if (fp->_offset != _IO_pos_BAD) |
1378 | _IO_pos_adjust (fp->_offset, count); |
1379 | } |
1380 | } |
1381 | |
1382 | return n - want; |
1383 | } |
1384 | libc_hidden_def (_IO_file_xsgetn) |
1385 | |
1386 | static _IO_size_t |
1387 | _IO_file_xsgetn_mmap (_IO_FILE *fp, void *data, _IO_size_t n) |
1388 | { |
1389 | _IO_size_t have; |
1390 | char *read_ptr = fp->_IO_read_ptr; |
1391 | char *s = (char *) data; |
1392 | |
1393 | have = fp->_IO_read_end - fp->_IO_read_ptr; |
1394 | |
1395 | if (have < n) |
1396 | { |
1397 | if (__glibc_unlikely (_IO_in_backup (fp))) |
1398 | { |
1399 | s = __mempcpy (s, read_ptr, have); |
1400 | n -= have; |
1401 | _IO_switch_to_main_get_area (fp); |
1402 | read_ptr = fp->_IO_read_ptr; |
1403 | have = fp->_IO_read_end - fp->_IO_read_ptr; |
1404 | } |
1405 | |
1406 | if (have < n) |
1407 | { |
1408 | /* Check that we are mapping all of the file, in case it grew. */ |
1409 | if (__glibc_unlikely (mmap_remap_check (fp))) |
1410 | /* We punted mmap, so complete with the vanilla code. */ |
1411 | return s - (char *) data + _IO_XSGETN (fp, data, n); |
1412 | |
1413 | read_ptr = fp->_IO_read_ptr; |
1414 | have = fp->_IO_read_end - read_ptr; |
1415 | } |
1416 | } |
1417 | |
1418 | if (have < n) |
1419 | fp->_flags |= _IO_EOF_SEEN; |
1420 | |
1421 | if (have != 0) |
1422 | { |
1423 | have = MIN (have, n); |
1424 | s = __mempcpy (s, read_ptr, have); |
1425 | fp->_IO_read_ptr = read_ptr + have; |
1426 | } |
1427 | |
1428 | return s - (char *) data; |
1429 | } |
1430 | |
1431 | static _IO_size_t |
1432 | _IO_file_xsgetn_maybe_mmap (_IO_FILE *fp, void *data, _IO_size_t n) |
1433 | { |
1434 | /* We only get here if this is the first attempt to read something. |
1435 | Decide which operations to use and then punt to the chosen one. */ |
1436 | |
1437 | decide_maybe_mmap (fp); |
1438 | return _IO_XSGETN (fp, data, n); |
1439 | } |
1440 | |
1441 | versioned_symbol (libc, _IO_new_do_write, _IO_do_write, GLIBC_2_1); |
1442 | versioned_symbol (libc, _IO_new_file_attach, _IO_file_attach, GLIBC_2_1); |
1443 | versioned_symbol (libc, _IO_new_file_close_it, _IO_file_close_it, GLIBC_2_1); |
1444 | versioned_symbol (libc, _IO_new_file_finish, _IO_file_finish, GLIBC_2_1); |
1445 | versioned_symbol (libc, _IO_new_file_fopen, _IO_file_fopen, GLIBC_2_1); |
1446 | versioned_symbol (libc, _IO_new_file_init, _IO_file_init, GLIBC_2_1); |
1447 | versioned_symbol (libc, _IO_new_file_setbuf, _IO_file_setbuf, GLIBC_2_1); |
1448 | versioned_symbol (libc, _IO_new_file_sync, _IO_file_sync, GLIBC_2_1); |
1449 | versioned_symbol (libc, _IO_new_file_overflow, _IO_file_overflow, GLIBC_2_1); |
1450 | versioned_symbol (libc, _IO_new_file_seekoff, _IO_file_seekoff, GLIBC_2_1); |
1451 | versioned_symbol (libc, _IO_new_file_underflow, _IO_file_underflow, GLIBC_2_1); |
1452 | versioned_symbol (libc, _IO_new_file_write, _IO_file_write, GLIBC_2_1); |
1453 | versioned_symbol (libc, _IO_new_file_xsputn, _IO_file_xsputn, GLIBC_2_1); |
1454 | |
1455 | const struct _IO_jump_t _IO_file_jumps libio_vtable = |
1456 | { |
1457 | JUMP_INIT_DUMMY, |
1458 | JUMP_INIT(finish, _IO_file_finish), |
1459 | JUMP_INIT(overflow, _IO_file_overflow), |
1460 | JUMP_INIT(underflow, _IO_file_underflow), |
1461 | JUMP_INIT(uflow, _IO_default_uflow), |
1462 | JUMP_INIT(pbackfail, _IO_default_pbackfail), |
1463 | JUMP_INIT(xsputn, _IO_file_xsputn), |
1464 | JUMP_INIT(xsgetn, _IO_file_xsgetn), |
1465 | JUMP_INIT(seekoff, _IO_new_file_seekoff), |
1466 | JUMP_INIT(seekpos, _IO_default_seekpos), |
1467 | JUMP_INIT(setbuf, _IO_new_file_setbuf), |
1468 | JUMP_INIT(sync, _IO_new_file_sync), |
1469 | JUMP_INIT(doallocate, _IO_file_doallocate), |
1470 | JUMP_INIT(read, _IO_file_read), |
1471 | JUMP_INIT(write, _IO_new_file_write), |
1472 | JUMP_INIT(seek, _IO_file_seek), |
1473 | JUMP_INIT(close, _IO_file_close), |
1474 | JUMP_INIT(stat, _IO_file_stat), |
1475 | JUMP_INIT(showmanyc, _IO_default_showmanyc), |
1476 | JUMP_INIT(imbue, _IO_default_imbue) |
1477 | }; |
1478 | libc_hidden_data_def (_IO_file_jumps) |
1479 | |
1480 | const struct _IO_jump_t _IO_file_jumps_mmap libio_vtable = |
1481 | { |
1482 | JUMP_INIT_DUMMY, |
1483 | JUMP_INIT(finish, _IO_file_finish), |
1484 | JUMP_INIT(overflow, _IO_file_overflow), |
1485 | JUMP_INIT(underflow, _IO_file_underflow_mmap), |
1486 | JUMP_INIT(uflow, _IO_default_uflow), |
1487 | JUMP_INIT(pbackfail, _IO_default_pbackfail), |
1488 | JUMP_INIT(xsputn, _IO_new_file_xsputn), |
1489 | JUMP_INIT(xsgetn, _IO_file_xsgetn_mmap), |
1490 | JUMP_INIT(seekoff, _IO_file_seekoff_mmap), |
1491 | JUMP_INIT(seekpos, _IO_default_seekpos), |
1492 | JUMP_INIT(setbuf, (_IO_setbuf_t) _IO_file_setbuf_mmap), |
1493 | JUMP_INIT(sync, _IO_file_sync_mmap), |
1494 | JUMP_INIT(doallocate, _IO_file_doallocate), |
1495 | JUMP_INIT(read, _IO_file_read), |
1496 | JUMP_INIT(write, _IO_new_file_write), |
1497 | JUMP_INIT(seek, _IO_file_seek), |
1498 | JUMP_INIT(close, _IO_file_close_mmap), |
1499 | JUMP_INIT(stat, _IO_file_stat), |
1500 | JUMP_INIT(showmanyc, _IO_default_showmanyc), |
1501 | JUMP_INIT(imbue, _IO_default_imbue) |
1502 | }; |
1503 | |
1504 | const struct _IO_jump_t _IO_file_jumps_maybe_mmap libio_vtable = |
1505 | { |
1506 | JUMP_INIT_DUMMY, |
1507 | JUMP_INIT(finish, _IO_file_finish), |
1508 | JUMP_INIT(overflow, _IO_file_overflow), |
1509 | JUMP_INIT(underflow, _IO_file_underflow_maybe_mmap), |
1510 | JUMP_INIT(uflow, _IO_default_uflow), |
1511 | JUMP_INIT(pbackfail, _IO_default_pbackfail), |
1512 | JUMP_INIT(xsputn, _IO_new_file_xsputn), |
1513 | JUMP_INIT(xsgetn, _IO_file_xsgetn_maybe_mmap), |
1514 | JUMP_INIT(seekoff, _IO_file_seekoff_maybe_mmap), |
1515 | JUMP_INIT(seekpos, _IO_default_seekpos), |
1516 | JUMP_INIT(setbuf, (_IO_setbuf_t) _IO_file_setbuf_mmap), |
1517 | JUMP_INIT(sync, _IO_new_file_sync), |
1518 | JUMP_INIT(doallocate, _IO_file_doallocate), |
1519 | JUMP_INIT(read, _IO_file_read), |
1520 | JUMP_INIT(write, _IO_new_file_write), |
1521 | JUMP_INIT(seek, _IO_file_seek), |
1522 | JUMP_INIT(close, _IO_file_close), |
1523 | JUMP_INIT(stat, _IO_file_stat), |
1524 | JUMP_INIT(showmanyc, _IO_default_showmanyc), |
1525 | JUMP_INIT(imbue, _IO_default_imbue) |
1526 | }; |
1527 | |