Commit | Line | Data |
---|---|---|
93509525 | 1 | /* Low-level I/O routines for BFDs. |
7c192733 AC |
2 | |
3 | Copyright 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, | |
515ef31d | 4 | 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008 |
9553c638 | 5 | Free Software Foundation, Inc. |
7c192733 | 6 | |
93509525 KD |
7 | Written by Cygnus Support. |
8 | ||
cd123cb7 | 9 | This file is part of BFD, the Binary File Descriptor library. |
93509525 | 10 | |
cd123cb7 NC |
11 | This program is free software; you can redistribute it and/or modify |
12 | it under the terms of the GNU General Public License as published by | |
13 | the Free Software Foundation; either version 3 of the License, or | |
14 | (at your option) any later version. | |
93509525 | 15 | |
cd123cb7 NC |
16 | This program is distributed in the hope that it will be useful, |
17 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
18 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
19 | GNU General Public License for more details. | |
93509525 | 20 | |
cd123cb7 NC |
21 | You should have received a copy of the GNU General Public License |
22 | along with this program; if not, write to the Free Software | |
23 | Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, | |
24 | MA 02110-1301, USA. */ | |
93509525 KD |
25 | |
26 | #include "sysdep.h" | |
3db64b00 | 27 | #include <limits.h> |
93509525 KD |
28 | #include "bfd.h" |
29 | #include "libbfd.h" | |
30 | ||
93509525 KD |
31 | #ifndef S_IXUSR |
32 | #define S_IXUSR 0100 /* Execute by owner. */ | |
33 | #endif | |
34 | #ifndef S_IXGRP | |
35 | #define S_IXGRP 0010 /* Execute by group. */ | |
36 | #endif | |
37 | #ifndef S_IXOTH | |
38 | #define S_IXOTH 0001 /* Execute by others. */ | |
39 | #endif | |
40 | ||
428b207a TT |
41 | #ifndef FD_CLOEXEC |
42 | #define FD_CLOEXEC 1 | |
43 | #endif | |
44 | ||
7c192733 AC |
45 | file_ptr |
46 | real_ftell (FILE *file) | |
47 | { | |
48 | #if defined (HAVE_FTELLO64) | |
49 | return ftello64 (file); | |
50 | #elif defined (HAVE_FTELLO) | |
51 | return ftello (file); | |
52 | #else | |
53 | return ftell (file); | |
54 | #endif | |
55 | } | |
56 | ||
57 | int | |
58 | real_fseek (FILE *file, file_ptr offset, int whence) | |
59 | { | |
60 | #if defined (HAVE_FSEEKO64) | |
61 | return fseeko64 (file, offset, whence); | |
62 | #elif defined (HAVE_FSEEKO) | |
63 | return fseeko (file, offset, whence); | |
64 | #else | |
65 | return fseek (file, offset, whence); | |
66 | #endif | |
67 | } | |
68 | ||
428b207a TT |
69 | /* Mark FILE as close-on-exec. Return FILE. FILE may be NULL, in |
70 | which case nothing is done. */ | |
71 | static FILE * | |
72 | close_on_exec (FILE *file) | |
73 | { | |
74 | #if defined (HAVE_FILENO) && defined (F_GETFD) | |
75 | if (file) | |
76 | { | |
77 | int fd = fileno (file); | |
78 | int old = fcntl (fd, F_GETFD, 0); | |
79 | if (old >= 0) | |
80 | fcntl (fd, F_SETFD, old | FD_CLOEXEC); | |
81 | } | |
82 | #endif | |
83 | return file; | |
84 | } | |
85 | ||
2e6f4fae DJ |
86 | FILE * |
87 | real_fopen (const char *filename, const char *modes) | |
88 | { | |
d387240a TG |
89 | #ifdef VMS |
90 | char vms_modes[4]; | |
91 | char *vms_attr; | |
92 | ||
93 | /* On VMS, fopen allows file attributes as optionnal arguments. | |
94 | We need to use them but we'd better to use the common prototype. | |
95 | In fopen-vms.h, they are separated from the mode with a comma. | |
96 | Split here. */ | |
97 | vms_attr = strchr (modes, ','); | |
98 | if (vms_attr == NULL) | |
99 | { | |
100 | /* No attributes. */ | |
101 | return close_on_exec (fopen (filename, modes)); | |
102 | } | |
103 | else | |
104 | { | |
0c376465 TG |
105 | /* Attributes found. Split. */ |
106 | size_t modes_len = strlen (modes) + 1; | |
107 | char attrs[modes_len + 1]; | |
108 | char *at[3]; | |
109 | int i; | |
110 | ||
111 | memcpy (attrs, modes, modes_len); | |
112 | at[0] = attrs; | |
113 | for (i = 0; i < 2; i++) | |
114 | { | |
115 | at[i + 1] = strchr (at[i], ','); | |
116 | BFD_ASSERT (at[i + 1] != NULL); | |
117 | *(at[i + 1]++) = 0; /* Replace ',' with a nul, and skip it. */ | |
118 | } | |
119 | return close_on_exec (fopen (filename, at[0], at[1], at[2])); | |
d387240a TG |
120 | } |
121 | #else /* !VMS */ | |
2e6f4fae | 122 | #if defined (HAVE_FOPEN64) |
428b207a | 123 | return close_on_exec (fopen64 (filename, modes)); |
2e6f4fae | 124 | #else |
428b207a | 125 | return close_on_exec (fopen (filename, modes)); |
2e6f4fae | 126 | #endif |
d387240a | 127 | #endif /* !VMS */ |
2e6f4fae DJ |
128 | } |
129 | ||
40838a72 AC |
130 | /* |
131 | INTERNAL_DEFINITION | |
132 | struct bfd_iovec | |
93509525 | 133 | |
40838a72 | 134 | DESCRIPTION |
93509525 | 135 | |
40838a72 AC |
136 | The <<struct bfd_iovec>> contains the internal file I/O class. |
137 | Each <<BFD>> has an instance of this class and all file I/O is | |
138 | routed through it (it is assumed that the instance implements | |
139 | all methods listed below). | |
140 | ||
141 | .struct bfd_iovec | |
142 | .{ | |
143 | . {* To avoid problems with macros, a "b" rather than "f" | |
144 | . prefix is prepended to each method name. *} | |
145 | . {* Attempt to read/write NBYTES on ABFD's IOSTREAM storing/fetching | |
146 | . bytes starting at PTR. Return the number of bytes actually | |
147 | . transfered (a read past end-of-file returns less than NBYTES), | |
148 | . or -1 (setting <<bfd_error>>) if an error occurs. *} | |
149 | . file_ptr (*bread) (struct bfd *abfd, void *ptr, file_ptr nbytes); | |
150 | . file_ptr (*bwrite) (struct bfd *abfd, const void *ptr, | |
151 | . file_ptr nbytes); | |
152 | . {* Return the current IOSTREAM file offset, or -1 (setting <<bfd_error>> | |
153 | . if an error occurs. *} | |
154 | . file_ptr (*btell) (struct bfd *abfd); | |
155 | . {* For the following, on successful completion a value of 0 is returned. | |
156 | . Otherwise, a value of -1 is returned (and <<bfd_error>> is set). *} | |
157 | . int (*bseek) (struct bfd *abfd, file_ptr offset, int whence); | |
158 | . int (*bclose) (struct bfd *abfd); | |
159 | . int (*bflush) (struct bfd *abfd); | |
160 | . int (*bstat) (struct bfd *abfd, struct stat *sb); | |
25b88f33 PP |
161 | . void* (*bmmap) (struct bfd *abfd, void *addr, bfd_size_type len, |
162 | . int prot, int flags, file_ptr offset); | |
40838a72 | 163 | .}; |
93509525 | 164 | |
40838a72 | 165 | */ |
93509525 | 166 | |
93509525 KD |
167 | |
168 | /* Return value is amount read. */ | |
169 | ||
170 | bfd_size_type | |
c58b9523 | 171 | bfd_bread (void *ptr, bfd_size_type size, bfd *abfd) |
93509525 KD |
172 | { |
173 | size_t nread; | |
174 | ||
1fb41da4 AM |
175 | /* If this is an archive element, don't read past the end of |
176 | this element. */ | |
177 | if (abfd->arelt_data != NULL) | |
178 | { | |
179 | size_t maxbytes = ((struct areltdata *) abfd->arelt_data)->parsed_size; | |
180 | if (size > maxbytes) | |
181 | size = maxbytes; | |
182 | } | |
183 | ||
93509525 KD |
184 | if ((abfd->flags & BFD_IN_MEMORY) != 0) |
185 | { | |
186 | struct bfd_in_memory *bim; | |
187 | bfd_size_type get; | |
188 | ||
c58b9523 | 189 | bim = abfd->iostream; |
93509525 KD |
190 | get = size; |
191 | if (abfd->where + get > bim->size) | |
192 | { | |
193 | if (bim->size < (bfd_size_type) abfd->where) | |
194 | get = 0; | |
195 | else | |
196 | get = bim->size - abfd->where; | |
197 | bfd_set_error (bfd_error_file_truncated); | |
198 | } | |
199 | memcpy (ptr, bim->buffer + abfd->where, (size_t) get); | |
200 | abfd->where += get; | |
201 | return get; | |
202 | } | |
203 | ||
69fd4758 NC |
204 | if (abfd->iovec) |
205 | nread = abfd->iovec->bread (abfd, ptr, size); | |
206 | else | |
207 | nread = 0; | |
93509525 KD |
208 | if (nread != (size_t) -1) |
209 | abfd->where += nread; | |
210 | ||
93509525 KD |
211 | return nread; |
212 | } | |
213 | ||
214 | bfd_size_type | |
c58b9523 | 215 | bfd_bwrite (const void *ptr, bfd_size_type size, bfd *abfd) |
93509525 KD |
216 | { |
217 | size_t nwrote; | |
218 | ||
219 | if ((abfd->flags & BFD_IN_MEMORY) != 0) | |
220 | { | |
c58b9523 | 221 | struct bfd_in_memory *bim = abfd->iostream; |
69fd4758 | 222 | |
93509525 KD |
223 | size = (size_t) size; |
224 | if (abfd->where + size > bim->size) | |
225 | { | |
226 | bfd_size_type newsize, oldsize; | |
227 | ||
228 | oldsize = (bim->size + 127) & ~(bfd_size_type) 127; | |
229 | bim->size = abfd->where + size; | |
230 | /* Round up to cut down on memory fragmentation */ | |
231 | newsize = (bim->size + 127) & ~(bfd_size_type) 127; | |
232 | if (newsize > oldsize) | |
233 | { | |
515ef31d NC |
234 | bim->buffer = bfd_realloc_or_free (bim->buffer, newsize); |
235 | if (bim->buffer == NULL) | |
93509525 KD |
236 | { |
237 | bim->size = 0; | |
238 | return 0; | |
239 | } | |
5c93f09b AM |
240 | if (newsize > bim->size) |
241 | memset (bim->buffer + bim->size, 0, newsize - bim->size); | |
93509525 KD |
242 | } |
243 | } | |
244 | memcpy (bim->buffer + abfd->where, ptr, (size_t) size); | |
245 | abfd->where += size; | |
246 | return size; | |
247 | } | |
248 | ||
69fd4758 NC |
249 | if (abfd->iovec) |
250 | nwrote = abfd->iovec->bwrite (abfd, ptr, size); | |
251 | else | |
252 | nwrote = 0; | |
253 | ||
93509525 KD |
254 | if (nwrote != (size_t) -1) |
255 | abfd->where += nwrote; | |
256 | if (nwrote != size) | |
257 | { | |
258 | #ifdef ENOSPC | |
259 | errno = ENOSPC; | |
260 | #endif | |
261 | bfd_set_error (bfd_error_system_call); | |
262 | } | |
263 | return nwrote; | |
264 | } | |
265 | ||
7c192733 | 266 | file_ptr |
c58b9523 | 267 | bfd_tell (bfd *abfd) |
93509525 KD |
268 | { |
269 | file_ptr ptr; | |
270 | ||
271 | if ((abfd->flags & BFD_IN_MEMORY) != 0) | |
272 | return abfd->where; | |
273 | ||
69fd4758 NC |
274 | if (abfd->iovec) |
275 | { | |
276 | ptr = abfd->iovec->btell (abfd); | |
277 | ||
278 | if (abfd->my_archive) | |
279 | ptr -= abfd->origin; | |
280 | } | |
281 | else | |
282 | ptr = 0; | |
93509525 | 283 | |
93509525 KD |
284 | abfd->where = ptr; |
285 | return ptr; | |
286 | } | |
287 | ||
288 | int | |
c58b9523 | 289 | bfd_flush (bfd *abfd) |
93509525 KD |
290 | { |
291 | if ((abfd->flags & BFD_IN_MEMORY) != 0) | |
292 | return 0; | |
69fd4758 NC |
293 | |
294 | if (abfd->iovec) | |
295 | return abfd->iovec->bflush (abfd); | |
296 | return 0; | |
93509525 KD |
297 | } |
298 | ||
299 | /* Returns 0 for success, negative value for failure (in which case | |
300 | bfd_get_error can retrieve the error code). */ | |
301 | int | |
c58b9523 | 302 | bfd_stat (bfd *abfd, struct stat *statbuf) |
93509525 | 303 | { |
93509525 KD |
304 | int result; |
305 | ||
306 | if ((abfd->flags & BFD_IN_MEMORY) != 0) | |
307 | abort (); | |
308 | ||
69fd4758 NC |
309 | if (abfd->iovec) |
310 | result = abfd->iovec->bstat (abfd, statbuf); | |
311 | else | |
312 | result = -1; | |
313 | ||
93509525 KD |
314 | if (result < 0) |
315 | bfd_set_error (bfd_error_system_call); | |
316 | return result; | |
317 | } | |
318 | ||
319 | /* Returns 0 for success, nonzero for failure (in which case bfd_get_error | |
320 | can retrieve the error code). */ | |
321 | ||
322 | int | |
c58b9523 | 323 | bfd_seek (bfd *abfd, file_ptr position, int direction) |
93509525 KD |
324 | { |
325 | int result; | |
7c192733 | 326 | file_ptr file_position; |
93509525 KD |
327 | /* For the time being, a BFD may not seek to it's end. The problem |
328 | is that we don't easily have a way to recognize the end of an | |
329 | element in an archive. */ | |
330 | ||
331 | BFD_ASSERT (direction == SEEK_SET || direction == SEEK_CUR); | |
332 | ||
333 | if (direction == SEEK_CUR && position == 0) | |
334 | return 0; | |
335 | ||
336 | if ((abfd->flags & BFD_IN_MEMORY) != 0) | |
337 | { | |
338 | struct bfd_in_memory *bim; | |
339 | ||
c58b9523 | 340 | bim = abfd->iostream; |
93509525 KD |
341 | |
342 | if (direction == SEEK_SET) | |
343 | abfd->where = position; | |
344 | else | |
345 | abfd->where += position; | |
346 | ||
347 | if (abfd->where > bim->size) | |
348 | { | |
5c93f09b AM |
349 | if (abfd->direction == write_direction |
350 | || abfd->direction == both_direction) | |
93509525 KD |
351 | { |
352 | bfd_size_type newsize, oldsize; | |
69fd4758 | 353 | |
93509525 KD |
354 | oldsize = (bim->size + 127) & ~(bfd_size_type) 127; |
355 | bim->size = abfd->where; | |
356 | /* Round up to cut down on memory fragmentation */ | |
357 | newsize = (bim->size + 127) & ~(bfd_size_type) 127; | |
358 | if (newsize > oldsize) | |
359 | { | |
515ef31d NC |
360 | bim->buffer = bfd_realloc_or_free (bim->buffer, newsize); |
361 | if (bim->buffer == NULL) | |
93509525 KD |
362 | { |
363 | bim->size = 0; | |
364 | return -1; | |
365 | } | |
5c93f09b | 366 | memset (bim->buffer + oldsize, 0, newsize - oldsize); |
93509525 KD |
367 | } |
368 | } | |
369 | else | |
370 | { | |
371 | abfd->where = bim->size; | |
372 | bfd_set_error (bfd_error_file_truncated); | |
373 | return -1; | |
374 | } | |
375 | } | |
376 | return 0; | |
377 | } | |
378 | ||
379 | if (abfd->format != bfd_archive && abfd->my_archive == 0) | |
380 | { | |
93509525 KD |
381 | if (direction == SEEK_SET && (bfd_vma) position == abfd->where) |
382 | return 0; | |
383 | } | |
384 | else | |
385 | { | |
386 | /* We need something smarter to optimize access to archives. | |
387 | Currently, anything inside an archive is read via the file | |
388 | handle for the archive. Which means that a bfd_seek on one | |
389 | component affects the `current position' in the archive, as | |
390 | well as in any other component. | |
391 | ||
392 | It might be sufficient to put a spike through the cache | |
393 | abstraction, and look to the archive for the file position, | |
394 | but I think we should try for something cleaner. | |
395 | ||
396 | In the meantime, no optimization for archives. */ | |
397 | } | |
398 | ||
93509525 KD |
399 | file_position = position; |
400 | if (direction == SEEK_SET && abfd->my_archive != NULL) | |
401 | file_position += abfd->origin; | |
402 | ||
69fd4758 NC |
403 | if (abfd->iovec) |
404 | result = abfd->iovec->bseek (abfd, file_position, direction); | |
405 | else | |
406 | result = -1; | |
407 | ||
93509525 KD |
408 | if (result != 0) |
409 | { | |
410 | int hold_errno = errno; | |
411 | ||
412 | /* Force redetermination of `where' field. */ | |
413 | bfd_tell (abfd); | |
414 | ||
415 | /* An EINVAL error probably means that the file offset was | |
416 | absurd. */ | |
417 | if (hold_errno == EINVAL) | |
418 | bfd_set_error (bfd_error_file_truncated); | |
419 | else | |
420 | { | |
421 | bfd_set_error (bfd_error_system_call); | |
422 | errno = hold_errno; | |
423 | } | |
424 | } | |
425 | else | |
426 | { | |
427 | /* Adjust `where' field. */ | |
428 | if (direction == SEEK_SET) | |
429 | abfd->where = position; | |
430 | else | |
431 | abfd->where += position; | |
432 | } | |
433 | return result; | |
434 | } | |
435 | ||
436 | /* | |
437 | FUNCTION | |
438 | bfd_get_mtime | |
439 | ||
440 | SYNOPSIS | |
c58b9523 | 441 | long bfd_get_mtime (bfd *abfd); |
93509525 KD |
442 | |
443 | DESCRIPTION | |
444 | Return the file modification time (as read from the file system, or | |
445 | from the archive header for archive members). | |
446 | ||
447 | */ | |
448 | ||
449 | long | |
c58b9523 | 450 | bfd_get_mtime (bfd *abfd) |
93509525 | 451 | { |
93509525 KD |
452 | struct stat buf; |
453 | ||
454 | if (abfd->mtime_set) | |
455 | return abfd->mtime; | |
456 | ||
69fd4758 NC |
457 | if (abfd->iovec == NULL) |
458 | return 0; | |
459 | ||
40838a72 | 460 | if (abfd->iovec->bstat (abfd, &buf) != 0) |
93509525 KD |
461 | return 0; |
462 | ||
463 | abfd->mtime = buf.st_mtime; /* Save value in case anyone wants it */ | |
464 | return buf.st_mtime; | |
465 | } | |
466 | ||
467 | /* | |
468 | FUNCTION | |
469 | bfd_get_size | |
470 | ||
471 | SYNOPSIS | |
74633dd0 | 472 | file_ptr bfd_get_size (bfd *abfd); |
93509525 KD |
473 | |
474 | DESCRIPTION | |
475 | Return the file size (as read from file system) for the file | |
476 | associated with BFD @var{abfd}. | |
477 | ||
478 | The initial motivation for, and use of, this routine is not | |
479 | so we can get the exact size of the object the BFD applies to, since | |
480 | that might not be generally possible (archive members for example). | |
481 | It would be ideal if someone could eventually modify | |
482 | it so that such results were guaranteed. | |
483 | ||
484 | Instead, we want to ask questions like "is this NNN byte sized | |
485 | object I'm about to try read from file offset YYY reasonable?" | |
486 | As as example of where we might do this, some object formats | |
487 | use string tables for which the first <<sizeof (long)>> bytes of the | |
488 | table contain the size of the table itself, including the size bytes. | |
489 | If an application tries to read what it thinks is one of these | |
490 | string tables, without some way to validate the size, and for | |
491 | some reason the size is wrong (byte swapping error, wrong location | |
492 | for the string table, etc.), the only clue is likely to be a read | |
493 | error when it tries to read the table, or a "virtual memory | |
494 | exhausted" error when it tries to allocate 15 bazillon bytes | |
495 | of space for the 15 bazillon byte table it is about to read. | |
5c4491d3 | 496 | This function at least allows us to answer the question, "is the |
93509525 KD |
497 | size reasonable?". |
498 | */ | |
499 | ||
74633dd0 | 500 | file_ptr |
c58b9523 | 501 | bfd_get_size (bfd *abfd) |
93509525 | 502 | { |
93509525 KD |
503 | struct stat buf; |
504 | ||
505 | if ((abfd->flags & BFD_IN_MEMORY) != 0) | |
506 | return ((struct bfd_in_memory *) abfd->iostream)->size; | |
507 | ||
69fd4758 NC |
508 | if (abfd->iovec == NULL) |
509 | return 0; | |
510 | ||
40838a72 | 511 | if (abfd->iovec->bstat (abfd, &buf) != 0) |
93509525 KD |
512 | return 0; |
513 | ||
514 | return buf.st_size; | |
515 | } | |
25b88f33 PP |
516 | |
517 | ||
518 | /* | |
519 | FUNCTION | |
520 | bfd_mmap | |
521 | ||
522 | SYNOPSIS | |
523 | void *bfd_mmap (bfd *abfd, void *addr, bfd_size_type len, | |
524 | int prot, int flags, file_ptr offset); | |
525 | ||
526 | DESCRIPTION | |
527 | Return mmap()ed region of the file, if possible and implemented. | |
528 | ||
529 | */ | |
530 | ||
531 | void * | |
532 | bfd_mmap (bfd *abfd, void *addr, bfd_size_type len, | |
533 | int prot, int flags, file_ptr offset) | |
534 | { | |
535 | void *ret = (void *)-1; | |
536 | if ((abfd->flags & BFD_IN_MEMORY) != 0) | |
537 | return ret; | |
538 | ||
539 | if (abfd->iovec == NULL) | |
540 | return ret; | |
541 | ||
542 | return abfd->iovec->bmmap (abfd, addr, len, prot, flags, offset); | |
543 | } |