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 | { | |
105 | /* Attribute found - rebuild modes. */ | |
106 | size_t modes_len = vms_attr - modes; | |
107 | ||
108 | BFD_ASSERT (modes_len < sizeof (vms_modes)); | |
109 | memcpy (vms_modes, modes, modes_len); | |
110 | vms_modes[modes_len] = 0; | |
111 | return close_on_exec (fopen (filename, vms_modes, vms_attr + 1)); | |
112 | } | |
113 | #else /* !VMS */ | |
2e6f4fae | 114 | #if defined (HAVE_FOPEN64) |
428b207a | 115 | return close_on_exec (fopen64 (filename, modes)); |
2e6f4fae | 116 | #else |
428b207a | 117 | return close_on_exec (fopen (filename, modes)); |
2e6f4fae | 118 | #endif |
d387240a | 119 | #endif /* !VMS */ |
2e6f4fae DJ |
120 | } |
121 | ||
40838a72 AC |
122 | /* |
123 | INTERNAL_DEFINITION | |
124 | struct bfd_iovec | |
93509525 | 125 | |
40838a72 | 126 | DESCRIPTION |
93509525 | 127 | |
40838a72 AC |
128 | The <<struct bfd_iovec>> contains the internal file I/O class. |
129 | Each <<BFD>> has an instance of this class and all file I/O is | |
130 | routed through it (it is assumed that the instance implements | |
131 | all methods listed below). | |
132 | ||
133 | .struct bfd_iovec | |
134 | .{ | |
135 | . {* To avoid problems with macros, a "b" rather than "f" | |
136 | . prefix is prepended to each method name. *} | |
137 | . {* Attempt to read/write NBYTES on ABFD's IOSTREAM storing/fetching | |
138 | . bytes starting at PTR. Return the number of bytes actually | |
139 | . transfered (a read past end-of-file returns less than NBYTES), | |
140 | . or -1 (setting <<bfd_error>>) if an error occurs. *} | |
141 | . file_ptr (*bread) (struct bfd *abfd, void *ptr, file_ptr nbytes); | |
142 | . file_ptr (*bwrite) (struct bfd *abfd, const void *ptr, | |
143 | . file_ptr nbytes); | |
144 | . {* Return the current IOSTREAM file offset, or -1 (setting <<bfd_error>> | |
145 | . if an error occurs. *} | |
146 | . file_ptr (*btell) (struct bfd *abfd); | |
147 | . {* For the following, on successful completion a value of 0 is returned. | |
148 | . Otherwise, a value of -1 is returned (and <<bfd_error>> is set). *} | |
149 | . int (*bseek) (struct bfd *abfd, file_ptr offset, int whence); | |
150 | . int (*bclose) (struct bfd *abfd); | |
151 | . int (*bflush) (struct bfd *abfd); | |
152 | . int (*bstat) (struct bfd *abfd, struct stat *sb); | |
153 | .}; | |
93509525 | 154 | |
40838a72 | 155 | */ |
93509525 | 156 | |
93509525 KD |
157 | |
158 | /* Return value is amount read. */ | |
159 | ||
160 | bfd_size_type | |
c58b9523 | 161 | bfd_bread (void *ptr, bfd_size_type size, bfd *abfd) |
93509525 KD |
162 | { |
163 | size_t nread; | |
164 | ||
1fb41da4 AM |
165 | /* If this is an archive element, don't read past the end of |
166 | this element. */ | |
167 | if (abfd->arelt_data != NULL) | |
168 | { | |
169 | size_t maxbytes = ((struct areltdata *) abfd->arelt_data)->parsed_size; | |
170 | if (size > maxbytes) | |
171 | size = maxbytes; | |
172 | } | |
173 | ||
93509525 KD |
174 | if ((abfd->flags & BFD_IN_MEMORY) != 0) |
175 | { | |
176 | struct bfd_in_memory *bim; | |
177 | bfd_size_type get; | |
178 | ||
c58b9523 | 179 | bim = abfd->iostream; |
93509525 KD |
180 | get = size; |
181 | if (abfd->where + get > bim->size) | |
182 | { | |
183 | if (bim->size < (bfd_size_type) abfd->where) | |
184 | get = 0; | |
185 | else | |
186 | get = bim->size - abfd->where; | |
187 | bfd_set_error (bfd_error_file_truncated); | |
188 | } | |
189 | memcpy (ptr, bim->buffer + abfd->where, (size_t) get); | |
190 | abfd->where += get; | |
191 | return get; | |
192 | } | |
193 | ||
69fd4758 NC |
194 | if (abfd->iovec) |
195 | nread = abfd->iovec->bread (abfd, ptr, size); | |
196 | else | |
197 | nread = 0; | |
93509525 KD |
198 | if (nread != (size_t) -1) |
199 | abfd->where += nread; | |
200 | ||
93509525 KD |
201 | return nread; |
202 | } | |
203 | ||
204 | bfd_size_type | |
c58b9523 | 205 | bfd_bwrite (const void *ptr, bfd_size_type size, bfd *abfd) |
93509525 KD |
206 | { |
207 | size_t nwrote; | |
208 | ||
209 | if ((abfd->flags & BFD_IN_MEMORY) != 0) | |
210 | { | |
c58b9523 | 211 | struct bfd_in_memory *bim = abfd->iostream; |
69fd4758 | 212 | |
93509525 KD |
213 | size = (size_t) size; |
214 | if (abfd->where + size > bim->size) | |
215 | { | |
216 | bfd_size_type newsize, oldsize; | |
217 | ||
218 | oldsize = (bim->size + 127) & ~(bfd_size_type) 127; | |
219 | bim->size = abfd->where + size; | |
220 | /* Round up to cut down on memory fragmentation */ | |
221 | newsize = (bim->size + 127) & ~(bfd_size_type) 127; | |
222 | if (newsize > oldsize) | |
223 | { | |
515ef31d NC |
224 | bim->buffer = bfd_realloc_or_free (bim->buffer, newsize); |
225 | if (bim->buffer == NULL) | |
93509525 KD |
226 | { |
227 | bim->size = 0; | |
228 | return 0; | |
229 | } | |
230 | } | |
231 | } | |
232 | memcpy (bim->buffer + abfd->where, ptr, (size_t) size); | |
233 | abfd->where += size; | |
234 | return size; | |
235 | } | |
236 | ||
69fd4758 NC |
237 | if (abfd->iovec) |
238 | nwrote = abfd->iovec->bwrite (abfd, ptr, size); | |
239 | else | |
240 | nwrote = 0; | |
241 | ||
93509525 KD |
242 | if (nwrote != (size_t) -1) |
243 | abfd->where += nwrote; | |
244 | if (nwrote != size) | |
245 | { | |
246 | #ifdef ENOSPC | |
247 | errno = ENOSPC; | |
248 | #endif | |
249 | bfd_set_error (bfd_error_system_call); | |
250 | } | |
251 | return nwrote; | |
252 | } | |
253 | ||
7c192733 | 254 | file_ptr |
c58b9523 | 255 | bfd_tell (bfd *abfd) |
93509525 KD |
256 | { |
257 | file_ptr ptr; | |
258 | ||
259 | if ((abfd->flags & BFD_IN_MEMORY) != 0) | |
260 | return abfd->where; | |
261 | ||
69fd4758 NC |
262 | if (abfd->iovec) |
263 | { | |
264 | ptr = abfd->iovec->btell (abfd); | |
265 | ||
266 | if (abfd->my_archive) | |
267 | ptr -= abfd->origin; | |
268 | } | |
269 | else | |
270 | ptr = 0; | |
93509525 | 271 | |
93509525 KD |
272 | abfd->where = ptr; |
273 | return ptr; | |
274 | } | |
275 | ||
276 | int | |
c58b9523 | 277 | bfd_flush (bfd *abfd) |
93509525 KD |
278 | { |
279 | if ((abfd->flags & BFD_IN_MEMORY) != 0) | |
280 | return 0; | |
69fd4758 NC |
281 | |
282 | if (abfd->iovec) | |
283 | return abfd->iovec->bflush (abfd); | |
284 | return 0; | |
93509525 KD |
285 | } |
286 | ||
287 | /* Returns 0 for success, negative value for failure (in which case | |
288 | bfd_get_error can retrieve the error code). */ | |
289 | int | |
c58b9523 | 290 | bfd_stat (bfd *abfd, struct stat *statbuf) |
93509525 | 291 | { |
93509525 KD |
292 | int result; |
293 | ||
294 | if ((abfd->flags & BFD_IN_MEMORY) != 0) | |
295 | abort (); | |
296 | ||
69fd4758 NC |
297 | if (abfd->iovec) |
298 | result = abfd->iovec->bstat (abfd, statbuf); | |
299 | else | |
300 | result = -1; | |
301 | ||
93509525 KD |
302 | if (result < 0) |
303 | bfd_set_error (bfd_error_system_call); | |
304 | return result; | |
305 | } | |
306 | ||
307 | /* Returns 0 for success, nonzero for failure (in which case bfd_get_error | |
308 | can retrieve the error code). */ | |
309 | ||
310 | int | |
c58b9523 | 311 | bfd_seek (bfd *abfd, file_ptr position, int direction) |
93509525 KD |
312 | { |
313 | int result; | |
7c192733 | 314 | file_ptr file_position; |
93509525 KD |
315 | /* For the time being, a BFD may not seek to it's end. The problem |
316 | is that we don't easily have a way to recognize the end of an | |
317 | element in an archive. */ | |
318 | ||
319 | BFD_ASSERT (direction == SEEK_SET || direction == SEEK_CUR); | |
320 | ||
321 | if (direction == SEEK_CUR && position == 0) | |
322 | return 0; | |
323 | ||
324 | if ((abfd->flags & BFD_IN_MEMORY) != 0) | |
325 | { | |
326 | struct bfd_in_memory *bim; | |
327 | ||
c58b9523 | 328 | bim = abfd->iostream; |
93509525 KD |
329 | |
330 | if (direction == SEEK_SET) | |
331 | abfd->where = position; | |
332 | else | |
333 | abfd->where += position; | |
334 | ||
335 | if (abfd->where > bim->size) | |
336 | { | |
337 | if ((abfd->direction == write_direction) || | |
338 | (abfd->direction == both_direction)) | |
339 | { | |
340 | bfd_size_type newsize, oldsize; | |
69fd4758 | 341 | |
93509525 KD |
342 | oldsize = (bim->size + 127) & ~(bfd_size_type) 127; |
343 | bim->size = abfd->where; | |
344 | /* Round up to cut down on memory fragmentation */ | |
345 | newsize = (bim->size + 127) & ~(bfd_size_type) 127; | |
346 | if (newsize > oldsize) | |
347 | { | |
515ef31d NC |
348 | bim->buffer = bfd_realloc_or_free (bim->buffer, newsize); |
349 | if (bim->buffer == NULL) | |
93509525 KD |
350 | { |
351 | bim->size = 0; | |
352 | return -1; | |
353 | } | |
354 | } | |
355 | } | |
356 | else | |
357 | { | |
358 | abfd->where = bim->size; | |
359 | bfd_set_error (bfd_error_file_truncated); | |
360 | return -1; | |
361 | } | |
362 | } | |
363 | return 0; | |
364 | } | |
365 | ||
366 | if (abfd->format != bfd_archive && abfd->my_archive == 0) | |
367 | { | |
93509525 KD |
368 | if (direction == SEEK_SET && (bfd_vma) position == abfd->where) |
369 | return 0; | |
370 | } | |
371 | else | |
372 | { | |
373 | /* We need something smarter to optimize access to archives. | |
374 | Currently, anything inside an archive is read via the file | |
375 | handle for the archive. Which means that a bfd_seek on one | |
376 | component affects the `current position' in the archive, as | |
377 | well as in any other component. | |
378 | ||
379 | It might be sufficient to put a spike through the cache | |
380 | abstraction, and look to the archive for the file position, | |
381 | but I think we should try for something cleaner. | |
382 | ||
383 | In the meantime, no optimization for archives. */ | |
384 | } | |
385 | ||
93509525 KD |
386 | file_position = position; |
387 | if (direction == SEEK_SET && abfd->my_archive != NULL) | |
388 | file_position += abfd->origin; | |
389 | ||
69fd4758 NC |
390 | if (abfd->iovec) |
391 | result = abfd->iovec->bseek (abfd, file_position, direction); | |
392 | else | |
393 | result = -1; | |
394 | ||
93509525 KD |
395 | if (result != 0) |
396 | { | |
397 | int hold_errno = errno; | |
398 | ||
399 | /* Force redetermination of `where' field. */ | |
400 | bfd_tell (abfd); | |
401 | ||
402 | /* An EINVAL error probably means that the file offset was | |
403 | absurd. */ | |
404 | if (hold_errno == EINVAL) | |
405 | bfd_set_error (bfd_error_file_truncated); | |
406 | else | |
407 | { | |
408 | bfd_set_error (bfd_error_system_call); | |
409 | errno = hold_errno; | |
410 | } | |
411 | } | |
412 | else | |
413 | { | |
414 | /* Adjust `where' field. */ | |
415 | if (direction == SEEK_SET) | |
416 | abfd->where = position; | |
417 | else | |
418 | abfd->where += position; | |
419 | } | |
420 | return result; | |
421 | } | |
422 | ||
423 | /* | |
424 | FUNCTION | |
425 | bfd_get_mtime | |
426 | ||
427 | SYNOPSIS | |
c58b9523 | 428 | long bfd_get_mtime (bfd *abfd); |
93509525 KD |
429 | |
430 | DESCRIPTION | |
431 | Return the file modification time (as read from the file system, or | |
432 | from the archive header for archive members). | |
433 | ||
434 | */ | |
435 | ||
436 | long | |
c58b9523 | 437 | bfd_get_mtime (bfd *abfd) |
93509525 | 438 | { |
93509525 KD |
439 | struct stat buf; |
440 | ||
441 | if (abfd->mtime_set) | |
442 | return abfd->mtime; | |
443 | ||
69fd4758 NC |
444 | if (abfd->iovec == NULL) |
445 | return 0; | |
446 | ||
40838a72 | 447 | if (abfd->iovec->bstat (abfd, &buf) != 0) |
93509525 KD |
448 | return 0; |
449 | ||
450 | abfd->mtime = buf.st_mtime; /* Save value in case anyone wants it */ | |
451 | return buf.st_mtime; | |
452 | } | |
453 | ||
454 | /* | |
455 | FUNCTION | |
456 | bfd_get_size | |
457 | ||
458 | SYNOPSIS | |
74633dd0 | 459 | file_ptr bfd_get_size (bfd *abfd); |
93509525 KD |
460 | |
461 | DESCRIPTION | |
462 | Return the file size (as read from file system) for the file | |
463 | associated with BFD @var{abfd}. | |
464 | ||
465 | The initial motivation for, and use of, this routine is not | |
466 | so we can get the exact size of the object the BFD applies to, since | |
467 | that might not be generally possible (archive members for example). | |
468 | It would be ideal if someone could eventually modify | |
469 | it so that such results were guaranteed. | |
470 | ||
471 | Instead, we want to ask questions like "is this NNN byte sized | |
472 | object I'm about to try read from file offset YYY reasonable?" | |
473 | As as example of where we might do this, some object formats | |
474 | use string tables for which the first <<sizeof (long)>> bytes of the | |
475 | table contain the size of the table itself, including the size bytes. | |
476 | If an application tries to read what it thinks is one of these | |
477 | string tables, without some way to validate the size, and for | |
478 | some reason the size is wrong (byte swapping error, wrong location | |
479 | for the string table, etc.), the only clue is likely to be a read | |
480 | error when it tries to read the table, or a "virtual memory | |
481 | exhausted" error when it tries to allocate 15 bazillon bytes | |
482 | of space for the 15 bazillon byte table it is about to read. | |
5c4491d3 | 483 | This function at least allows us to answer the question, "is the |
93509525 KD |
484 | size reasonable?". |
485 | */ | |
486 | ||
74633dd0 | 487 | file_ptr |
c58b9523 | 488 | bfd_get_size (bfd *abfd) |
93509525 | 489 | { |
93509525 KD |
490 | struct stat buf; |
491 | ||
492 | if ((abfd->flags & BFD_IN_MEMORY) != 0) | |
493 | return ((struct bfd_in_memory *) abfd->iostream)->size; | |
494 | ||
69fd4758 NC |
495 | if (abfd->iovec == NULL) |
496 | return 0; | |
497 | ||
40838a72 | 498 | if (abfd->iovec->bstat (abfd, &buf) != 0) |
93509525 KD |
499 | return 0; |
500 | ||
501 | return buf.st_size; | |
502 | } |