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, | |
3db64b00 | 4 | 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007 |
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 | ||
7c192733 AC |
41 | file_ptr |
42 | real_ftell (FILE *file) | |
43 | { | |
44 | #if defined (HAVE_FTELLO64) | |
45 | return ftello64 (file); | |
46 | #elif defined (HAVE_FTELLO) | |
47 | return ftello (file); | |
48 | #else | |
49 | return ftell (file); | |
50 | #endif | |
51 | } | |
52 | ||
53 | int | |
54 | real_fseek (FILE *file, file_ptr offset, int whence) | |
55 | { | |
56 | #if defined (HAVE_FSEEKO64) | |
57 | return fseeko64 (file, offset, whence); | |
58 | #elif defined (HAVE_FSEEKO) | |
59 | return fseeko (file, offset, whence); | |
60 | #else | |
61 | return fseek (file, offset, whence); | |
62 | #endif | |
63 | } | |
64 | ||
2e6f4fae DJ |
65 | FILE * |
66 | real_fopen (const char *filename, const char *modes) | |
67 | { | |
68 | #if defined (HAVE_FOPEN64) | |
69 | return fopen64 (filename, modes); | |
70 | #else | |
71 | return fopen (filename, modes); | |
72 | #endif | |
73 | } | |
74 | ||
40838a72 AC |
75 | /* |
76 | INTERNAL_DEFINITION | |
77 | struct bfd_iovec | |
93509525 | 78 | |
40838a72 | 79 | DESCRIPTION |
93509525 | 80 | |
40838a72 AC |
81 | The <<struct bfd_iovec>> contains the internal file I/O class. |
82 | Each <<BFD>> has an instance of this class and all file I/O is | |
83 | routed through it (it is assumed that the instance implements | |
84 | all methods listed below). | |
85 | ||
86 | .struct bfd_iovec | |
87 | .{ | |
88 | . {* To avoid problems with macros, a "b" rather than "f" | |
89 | . prefix is prepended to each method name. *} | |
90 | . {* Attempt to read/write NBYTES on ABFD's IOSTREAM storing/fetching | |
91 | . bytes starting at PTR. Return the number of bytes actually | |
92 | . transfered (a read past end-of-file returns less than NBYTES), | |
93 | . or -1 (setting <<bfd_error>>) if an error occurs. *} | |
94 | . file_ptr (*bread) (struct bfd *abfd, void *ptr, file_ptr nbytes); | |
95 | . file_ptr (*bwrite) (struct bfd *abfd, const void *ptr, | |
96 | . file_ptr nbytes); | |
97 | . {* Return the current IOSTREAM file offset, or -1 (setting <<bfd_error>> | |
98 | . if an error occurs. *} | |
99 | . file_ptr (*btell) (struct bfd *abfd); | |
100 | . {* For the following, on successful completion a value of 0 is returned. | |
101 | . Otherwise, a value of -1 is returned (and <<bfd_error>> is set). *} | |
102 | . int (*bseek) (struct bfd *abfd, file_ptr offset, int whence); | |
103 | . int (*bclose) (struct bfd *abfd); | |
104 | . int (*bflush) (struct bfd *abfd); | |
105 | . int (*bstat) (struct bfd *abfd, struct stat *sb); | |
106 | .}; | |
93509525 | 107 | |
40838a72 | 108 | */ |
93509525 | 109 | |
93509525 KD |
110 | |
111 | /* Return value is amount read. */ | |
112 | ||
113 | bfd_size_type | |
c58b9523 | 114 | bfd_bread (void *ptr, bfd_size_type size, bfd *abfd) |
93509525 KD |
115 | { |
116 | size_t nread; | |
117 | ||
1fb41da4 AM |
118 | /* If this is an archive element, don't read past the end of |
119 | this element. */ | |
120 | if (abfd->arelt_data != NULL) | |
121 | { | |
122 | size_t maxbytes = ((struct areltdata *) abfd->arelt_data)->parsed_size; | |
123 | if (size > maxbytes) | |
124 | size = maxbytes; | |
125 | } | |
126 | ||
93509525 KD |
127 | if ((abfd->flags & BFD_IN_MEMORY) != 0) |
128 | { | |
129 | struct bfd_in_memory *bim; | |
130 | bfd_size_type get; | |
131 | ||
c58b9523 | 132 | bim = abfd->iostream; |
93509525 KD |
133 | get = size; |
134 | if (abfd->where + get > bim->size) | |
135 | { | |
136 | if (bim->size < (bfd_size_type) abfd->where) | |
137 | get = 0; | |
138 | else | |
139 | get = bim->size - abfd->where; | |
140 | bfd_set_error (bfd_error_file_truncated); | |
141 | } | |
142 | memcpy (ptr, bim->buffer + abfd->where, (size_t) get); | |
143 | abfd->where += get; | |
144 | return get; | |
145 | } | |
146 | ||
69fd4758 NC |
147 | if (abfd->iovec) |
148 | nread = abfd->iovec->bread (abfd, ptr, size); | |
149 | else | |
150 | nread = 0; | |
93509525 KD |
151 | if (nread != (size_t) -1) |
152 | abfd->where += nread; | |
153 | ||
93509525 KD |
154 | return nread; |
155 | } | |
156 | ||
157 | bfd_size_type | |
c58b9523 | 158 | bfd_bwrite (const void *ptr, bfd_size_type size, bfd *abfd) |
93509525 KD |
159 | { |
160 | size_t nwrote; | |
161 | ||
162 | if ((abfd->flags & BFD_IN_MEMORY) != 0) | |
163 | { | |
c58b9523 | 164 | struct bfd_in_memory *bim = abfd->iostream; |
69fd4758 | 165 | |
93509525 KD |
166 | size = (size_t) size; |
167 | if (abfd->where + size > bim->size) | |
168 | { | |
169 | bfd_size_type newsize, oldsize; | |
170 | ||
171 | oldsize = (bim->size + 127) & ~(bfd_size_type) 127; | |
172 | bim->size = abfd->where + size; | |
173 | /* Round up to cut down on memory fragmentation */ | |
174 | newsize = (bim->size + 127) & ~(bfd_size_type) 127; | |
175 | if (newsize > oldsize) | |
176 | { | |
c58b9523 | 177 | bim->buffer = bfd_realloc (bim->buffer, newsize); |
93509525 KD |
178 | if (bim->buffer == 0) |
179 | { | |
180 | bim->size = 0; | |
181 | return 0; | |
182 | } | |
183 | } | |
184 | } | |
185 | memcpy (bim->buffer + abfd->where, ptr, (size_t) size); | |
186 | abfd->where += size; | |
187 | return size; | |
188 | } | |
189 | ||
69fd4758 NC |
190 | if (abfd->iovec) |
191 | nwrote = abfd->iovec->bwrite (abfd, ptr, size); | |
192 | else | |
193 | nwrote = 0; | |
194 | ||
93509525 KD |
195 | if (nwrote != (size_t) -1) |
196 | abfd->where += nwrote; | |
197 | if (nwrote != size) | |
198 | { | |
199 | #ifdef ENOSPC | |
200 | errno = ENOSPC; | |
201 | #endif | |
202 | bfd_set_error (bfd_error_system_call); | |
203 | } | |
204 | return nwrote; | |
205 | } | |
206 | ||
7c192733 | 207 | file_ptr |
c58b9523 | 208 | bfd_tell (bfd *abfd) |
93509525 KD |
209 | { |
210 | file_ptr ptr; | |
211 | ||
212 | if ((abfd->flags & BFD_IN_MEMORY) != 0) | |
213 | return abfd->where; | |
214 | ||
69fd4758 NC |
215 | if (abfd->iovec) |
216 | { | |
217 | ptr = abfd->iovec->btell (abfd); | |
218 | ||
219 | if (abfd->my_archive) | |
220 | ptr -= abfd->origin; | |
221 | } | |
222 | else | |
223 | ptr = 0; | |
93509525 | 224 | |
93509525 KD |
225 | abfd->where = ptr; |
226 | return ptr; | |
227 | } | |
228 | ||
229 | int | |
c58b9523 | 230 | bfd_flush (bfd *abfd) |
93509525 KD |
231 | { |
232 | if ((abfd->flags & BFD_IN_MEMORY) != 0) | |
233 | return 0; | |
69fd4758 NC |
234 | |
235 | if (abfd->iovec) | |
236 | return abfd->iovec->bflush (abfd); | |
237 | return 0; | |
93509525 KD |
238 | } |
239 | ||
240 | /* Returns 0 for success, negative value for failure (in which case | |
241 | bfd_get_error can retrieve the error code). */ | |
242 | int | |
c58b9523 | 243 | bfd_stat (bfd *abfd, struct stat *statbuf) |
93509525 | 244 | { |
93509525 KD |
245 | int result; |
246 | ||
247 | if ((abfd->flags & BFD_IN_MEMORY) != 0) | |
248 | abort (); | |
249 | ||
69fd4758 NC |
250 | if (abfd->iovec) |
251 | result = abfd->iovec->bstat (abfd, statbuf); | |
252 | else | |
253 | result = -1; | |
254 | ||
93509525 KD |
255 | if (result < 0) |
256 | bfd_set_error (bfd_error_system_call); | |
257 | return result; | |
258 | } | |
259 | ||
260 | /* Returns 0 for success, nonzero for failure (in which case bfd_get_error | |
261 | can retrieve the error code). */ | |
262 | ||
263 | int | |
c58b9523 | 264 | bfd_seek (bfd *abfd, file_ptr position, int direction) |
93509525 KD |
265 | { |
266 | int result; | |
7c192733 | 267 | file_ptr file_position; |
93509525 KD |
268 | /* For the time being, a BFD may not seek to it's end. The problem |
269 | is that we don't easily have a way to recognize the end of an | |
270 | element in an archive. */ | |
271 | ||
272 | BFD_ASSERT (direction == SEEK_SET || direction == SEEK_CUR); | |
273 | ||
274 | if (direction == SEEK_CUR && position == 0) | |
275 | return 0; | |
276 | ||
277 | if ((abfd->flags & BFD_IN_MEMORY) != 0) | |
278 | { | |
279 | struct bfd_in_memory *bim; | |
280 | ||
c58b9523 | 281 | bim = abfd->iostream; |
93509525 KD |
282 | |
283 | if (direction == SEEK_SET) | |
284 | abfd->where = position; | |
285 | else | |
286 | abfd->where += position; | |
287 | ||
288 | if (abfd->where > bim->size) | |
289 | { | |
290 | if ((abfd->direction == write_direction) || | |
291 | (abfd->direction == both_direction)) | |
292 | { | |
293 | bfd_size_type newsize, oldsize; | |
69fd4758 | 294 | |
93509525 KD |
295 | oldsize = (bim->size + 127) & ~(bfd_size_type) 127; |
296 | bim->size = abfd->where; | |
297 | /* Round up to cut down on memory fragmentation */ | |
298 | newsize = (bim->size + 127) & ~(bfd_size_type) 127; | |
299 | if (newsize > oldsize) | |
300 | { | |
c58b9523 | 301 | bim->buffer = bfd_realloc (bim->buffer, newsize); |
93509525 KD |
302 | if (bim->buffer == 0) |
303 | { | |
304 | bim->size = 0; | |
305 | return -1; | |
306 | } | |
307 | } | |
308 | } | |
309 | else | |
310 | { | |
311 | abfd->where = bim->size; | |
312 | bfd_set_error (bfd_error_file_truncated); | |
313 | return -1; | |
314 | } | |
315 | } | |
316 | return 0; | |
317 | } | |
318 | ||
319 | if (abfd->format != bfd_archive && abfd->my_archive == 0) | |
320 | { | |
93509525 KD |
321 | if (direction == SEEK_SET && (bfd_vma) position == abfd->where) |
322 | return 0; | |
323 | } | |
324 | else | |
325 | { | |
326 | /* We need something smarter to optimize access to archives. | |
327 | Currently, anything inside an archive is read via the file | |
328 | handle for the archive. Which means that a bfd_seek on one | |
329 | component affects the `current position' in the archive, as | |
330 | well as in any other component. | |
331 | ||
332 | It might be sufficient to put a spike through the cache | |
333 | abstraction, and look to the archive for the file position, | |
334 | but I think we should try for something cleaner. | |
335 | ||
336 | In the meantime, no optimization for archives. */ | |
337 | } | |
338 | ||
93509525 KD |
339 | file_position = position; |
340 | if (direction == SEEK_SET && abfd->my_archive != NULL) | |
341 | file_position += abfd->origin; | |
342 | ||
69fd4758 NC |
343 | if (abfd->iovec) |
344 | result = abfd->iovec->bseek (abfd, file_position, direction); | |
345 | else | |
346 | result = -1; | |
347 | ||
93509525 KD |
348 | if (result != 0) |
349 | { | |
350 | int hold_errno = errno; | |
351 | ||
352 | /* Force redetermination of `where' field. */ | |
353 | bfd_tell (abfd); | |
354 | ||
355 | /* An EINVAL error probably means that the file offset was | |
356 | absurd. */ | |
357 | if (hold_errno == EINVAL) | |
358 | bfd_set_error (bfd_error_file_truncated); | |
359 | else | |
360 | { | |
361 | bfd_set_error (bfd_error_system_call); | |
362 | errno = hold_errno; | |
363 | } | |
364 | } | |
365 | else | |
366 | { | |
367 | /* Adjust `where' field. */ | |
368 | if (direction == SEEK_SET) | |
369 | abfd->where = position; | |
370 | else | |
371 | abfd->where += position; | |
372 | } | |
373 | return result; | |
374 | } | |
375 | ||
376 | /* | |
377 | FUNCTION | |
378 | bfd_get_mtime | |
379 | ||
380 | SYNOPSIS | |
c58b9523 | 381 | long bfd_get_mtime (bfd *abfd); |
93509525 KD |
382 | |
383 | DESCRIPTION | |
384 | Return the file modification time (as read from the file system, or | |
385 | from the archive header for archive members). | |
386 | ||
387 | */ | |
388 | ||
389 | long | |
c58b9523 | 390 | bfd_get_mtime (bfd *abfd) |
93509525 | 391 | { |
93509525 KD |
392 | struct stat buf; |
393 | ||
394 | if (abfd->mtime_set) | |
395 | return abfd->mtime; | |
396 | ||
69fd4758 NC |
397 | if (abfd->iovec == NULL) |
398 | return 0; | |
399 | ||
40838a72 | 400 | if (abfd->iovec->bstat (abfd, &buf) != 0) |
93509525 KD |
401 | return 0; |
402 | ||
403 | abfd->mtime = buf.st_mtime; /* Save value in case anyone wants it */ | |
404 | return buf.st_mtime; | |
405 | } | |
406 | ||
407 | /* | |
408 | FUNCTION | |
409 | bfd_get_size | |
410 | ||
411 | SYNOPSIS | |
74633dd0 | 412 | file_ptr bfd_get_size (bfd *abfd); |
93509525 KD |
413 | |
414 | DESCRIPTION | |
415 | Return the file size (as read from file system) for the file | |
416 | associated with BFD @var{abfd}. | |
417 | ||
418 | The initial motivation for, and use of, this routine is not | |
419 | so we can get the exact size of the object the BFD applies to, since | |
420 | that might not be generally possible (archive members for example). | |
421 | It would be ideal if someone could eventually modify | |
422 | it so that such results were guaranteed. | |
423 | ||
424 | Instead, we want to ask questions like "is this NNN byte sized | |
425 | object I'm about to try read from file offset YYY reasonable?" | |
426 | As as example of where we might do this, some object formats | |
427 | use string tables for which the first <<sizeof (long)>> bytes of the | |
428 | table contain the size of the table itself, including the size bytes. | |
429 | If an application tries to read what it thinks is one of these | |
430 | string tables, without some way to validate the size, and for | |
431 | some reason the size is wrong (byte swapping error, wrong location | |
432 | for the string table, etc.), the only clue is likely to be a read | |
433 | error when it tries to read the table, or a "virtual memory | |
434 | exhausted" error when it tries to allocate 15 bazillon bytes | |
435 | of space for the 15 bazillon byte table it is about to read. | |
5c4491d3 | 436 | This function at least allows us to answer the question, "is the |
93509525 KD |
437 | size reasonable?". |
438 | */ | |
439 | ||
74633dd0 | 440 | file_ptr |
c58b9523 | 441 | bfd_get_size (bfd *abfd) |
93509525 | 442 | { |
93509525 KD |
443 | struct stat buf; |
444 | ||
445 | if ((abfd->flags & BFD_IN_MEMORY) != 0) | |
446 | return ((struct bfd_in_memory *) abfd->iostream)->size; | |
447 | ||
69fd4758 NC |
448 | if (abfd->iovec == NULL) |
449 | return 0; | |
450 | ||
40838a72 | 451 | if (abfd->iovec->bstat (abfd, &buf) != 0) |
93509525 KD |
452 | return 0; |
453 | ||
454 | return buf.st_size; | |
455 | } |