Commit | Line | Data |
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93509525 | 1 | /* Low-level I/O routines for BFDs. |
7c192733 AC |
2 | |
3 | Copyright 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, | |
1fb41da4 | 4 | 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006 |
9553c638 | 5 | Free Software Foundation, Inc. |
7c192733 | 6 | |
93509525 KD |
7 | Written by Cygnus Support. |
8 | ||
9 | This file is part of BFD, the Binary File Descriptor library. | |
10 | ||
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 2 of the License, or | |
14 | (at your option) any later version. | |
15 | ||
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. | |
20 | ||
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 | |
3e110533 | 23 | Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA. */ |
93509525 KD |
24 | |
25 | #include "sysdep.h" | |
26 | ||
27 | #include "bfd.h" | |
28 | #include "libbfd.h" | |
29 | ||
30 | #include <limits.h> | |
31 | ||
32 | #ifndef S_IXUSR | |
33 | #define S_IXUSR 0100 /* Execute by owner. */ | |
34 | #endif | |
35 | #ifndef S_IXGRP | |
36 | #define S_IXGRP 0010 /* Execute by group. */ | |
37 | #endif | |
38 | #ifndef S_IXOTH | |
39 | #define S_IXOTH 0001 /* Execute by others. */ | |
40 | #endif | |
41 | ||
7c192733 AC |
42 | file_ptr |
43 | real_ftell (FILE *file) | |
44 | { | |
45 | #if defined (HAVE_FTELLO64) | |
46 | return ftello64 (file); | |
47 | #elif defined (HAVE_FTELLO) | |
48 | return ftello (file); | |
49 | #else | |
50 | return ftell (file); | |
51 | #endif | |
52 | } | |
53 | ||
54 | int | |
55 | real_fseek (FILE *file, file_ptr offset, int whence) | |
56 | { | |
57 | #if defined (HAVE_FSEEKO64) | |
58 | return fseeko64 (file, offset, whence); | |
59 | #elif defined (HAVE_FSEEKO) | |
60 | return fseeko (file, offset, whence); | |
61 | #else | |
62 | return fseek (file, offset, whence); | |
63 | #endif | |
64 | } | |
65 | ||
2e6f4fae DJ |
66 | FILE * |
67 | real_fopen (const char *filename, const char *modes) | |
68 | { | |
69 | #if defined (HAVE_FOPEN64) | |
70 | return fopen64 (filename, modes); | |
71 | #else | |
72 | return fopen (filename, modes); | |
73 | #endif | |
74 | } | |
75 | ||
40838a72 AC |
76 | /* |
77 | INTERNAL_DEFINITION | |
78 | struct bfd_iovec | |
93509525 | 79 | |
40838a72 | 80 | DESCRIPTION |
93509525 | 81 | |
40838a72 AC |
82 | The <<struct bfd_iovec>> contains the internal file I/O class. |
83 | Each <<BFD>> has an instance of this class and all file I/O is | |
84 | routed through it (it is assumed that the instance implements | |
85 | all methods listed below). | |
86 | ||
87 | .struct bfd_iovec | |
88 | .{ | |
89 | . {* To avoid problems with macros, a "b" rather than "f" | |
90 | . prefix is prepended to each method name. *} | |
91 | . {* Attempt to read/write NBYTES on ABFD's IOSTREAM storing/fetching | |
92 | . bytes starting at PTR. Return the number of bytes actually | |
93 | . transfered (a read past end-of-file returns less than NBYTES), | |
94 | . or -1 (setting <<bfd_error>>) if an error occurs. *} | |
95 | . file_ptr (*bread) (struct bfd *abfd, void *ptr, file_ptr nbytes); | |
96 | . file_ptr (*bwrite) (struct bfd *abfd, const void *ptr, | |
97 | . file_ptr nbytes); | |
98 | . {* Return the current IOSTREAM file offset, or -1 (setting <<bfd_error>> | |
99 | . if an error occurs. *} | |
100 | . file_ptr (*btell) (struct bfd *abfd); | |
101 | . {* For the following, on successful completion a value of 0 is returned. | |
102 | . Otherwise, a value of -1 is returned (and <<bfd_error>> is set). *} | |
103 | . int (*bseek) (struct bfd *abfd, file_ptr offset, int whence); | |
104 | . int (*bclose) (struct bfd *abfd); | |
105 | . int (*bflush) (struct bfd *abfd); | |
106 | . int (*bstat) (struct bfd *abfd, struct stat *sb); | |
107 | .}; | |
93509525 | 108 | |
40838a72 | 109 | */ |
93509525 | 110 | |
93509525 KD |
111 | |
112 | /* Return value is amount read. */ | |
113 | ||
114 | bfd_size_type | |
c58b9523 | 115 | bfd_bread (void *ptr, bfd_size_type size, bfd *abfd) |
93509525 KD |
116 | { |
117 | size_t nread; | |
118 | ||
1fb41da4 AM |
119 | /* If this is an archive element, don't read past the end of |
120 | this element. */ | |
121 | if (abfd->arelt_data != NULL) | |
122 | { | |
123 | size_t maxbytes = ((struct areltdata *) abfd->arelt_data)->parsed_size; | |
124 | if (size > maxbytes) | |
125 | size = maxbytes; | |
126 | } | |
127 | ||
93509525 KD |
128 | if ((abfd->flags & BFD_IN_MEMORY) != 0) |
129 | { | |
130 | struct bfd_in_memory *bim; | |
131 | bfd_size_type get; | |
132 | ||
c58b9523 | 133 | bim = abfd->iostream; |
93509525 KD |
134 | get = size; |
135 | if (abfd->where + get > bim->size) | |
136 | { | |
137 | if (bim->size < (bfd_size_type) abfd->where) | |
138 | get = 0; | |
139 | else | |
140 | get = bim->size - abfd->where; | |
141 | bfd_set_error (bfd_error_file_truncated); | |
142 | } | |
143 | memcpy (ptr, bim->buffer + abfd->where, (size_t) get); | |
144 | abfd->where += get; | |
145 | return get; | |
146 | } | |
147 | ||
69fd4758 NC |
148 | if (abfd->iovec) |
149 | nread = abfd->iovec->bread (abfd, ptr, size); | |
150 | else | |
151 | nread = 0; | |
93509525 KD |
152 | if (nread != (size_t) -1) |
153 | abfd->where += nread; | |
154 | ||
93509525 KD |
155 | return nread; |
156 | } | |
157 | ||
158 | bfd_size_type | |
c58b9523 | 159 | bfd_bwrite (const void *ptr, bfd_size_type size, bfd *abfd) |
93509525 KD |
160 | { |
161 | size_t nwrote; | |
162 | ||
163 | if ((abfd->flags & BFD_IN_MEMORY) != 0) | |
164 | { | |
c58b9523 | 165 | struct bfd_in_memory *bim = abfd->iostream; |
69fd4758 | 166 | |
93509525 KD |
167 | size = (size_t) size; |
168 | if (abfd->where + size > bim->size) | |
169 | { | |
170 | bfd_size_type newsize, oldsize; | |
171 | ||
172 | oldsize = (bim->size + 127) & ~(bfd_size_type) 127; | |
173 | bim->size = abfd->where + size; | |
174 | /* Round up to cut down on memory fragmentation */ | |
175 | newsize = (bim->size + 127) & ~(bfd_size_type) 127; | |
176 | if (newsize > oldsize) | |
177 | { | |
c58b9523 | 178 | bim->buffer = bfd_realloc (bim->buffer, newsize); |
93509525 KD |
179 | if (bim->buffer == 0) |
180 | { | |
181 | bim->size = 0; | |
182 | return 0; | |
183 | } | |
184 | } | |
185 | } | |
186 | memcpy (bim->buffer + abfd->where, ptr, (size_t) size); | |
187 | abfd->where += size; | |
188 | return size; | |
189 | } | |
190 | ||
69fd4758 NC |
191 | if (abfd->iovec) |
192 | nwrote = abfd->iovec->bwrite (abfd, ptr, size); | |
193 | else | |
194 | nwrote = 0; | |
195 | ||
93509525 KD |
196 | if (nwrote != (size_t) -1) |
197 | abfd->where += nwrote; | |
198 | if (nwrote != size) | |
199 | { | |
200 | #ifdef ENOSPC | |
201 | errno = ENOSPC; | |
202 | #endif | |
203 | bfd_set_error (bfd_error_system_call); | |
204 | } | |
205 | return nwrote; | |
206 | } | |
207 | ||
7c192733 | 208 | file_ptr |
c58b9523 | 209 | bfd_tell (bfd *abfd) |
93509525 KD |
210 | { |
211 | file_ptr ptr; | |
212 | ||
213 | if ((abfd->flags & BFD_IN_MEMORY) != 0) | |
214 | return abfd->where; | |
215 | ||
69fd4758 NC |
216 | if (abfd->iovec) |
217 | { | |
218 | ptr = abfd->iovec->btell (abfd); | |
219 | ||
220 | if (abfd->my_archive) | |
221 | ptr -= abfd->origin; | |
222 | } | |
223 | else | |
224 | ptr = 0; | |
93509525 | 225 | |
93509525 KD |
226 | abfd->where = ptr; |
227 | return ptr; | |
228 | } | |
229 | ||
230 | int | |
c58b9523 | 231 | bfd_flush (bfd *abfd) |
93509525 KD |
232 | { |
233 | if ((abfd->flags & BFD_IN_MEMORY) != 0) | |
234 | return 0; | |
69fd4758 NC |
235 | |
236 | if (abfd->iovec) | |
237 | return abfd->iovec->bflush (abfd); | |
238 | return 0; | |
93509525 KD |
239 | } |
240 | ||
241 | /* Returns 0 for success, negative value for failure (in which case | |
242 | bfd_get_error can retrieve the error code). */ | |
243 | int | |
c58b9523 | 244 | bfd_stat (bfd *abfd, struct stat *statbuf) |
93509525 | 245 | { |
93509525 KD |
246 | int result; |
247 | ||
248 | if ((abfd->flags & BFD_IN_MEMORY) != 0) | |
249 | abort (); | |
250 | ||
69fd4758 NC |
251 | if (abfd->iovec) |
252 | result = abfd->iovec->bstat (abfd, statbuf); | |
253 | else | |
254 | result = -1; | |
255 | ||
93509525 KD |
256 | if (result < 0) |
257 | bfd_set_error (bfd_error_system_call); | |
258 | return result; | |
259 | } | |
260 | ||
261 | /* Returns 0 for success, nonzero for failure (in which case bfd_get_error | |
262 | can retrieve the error code). */ | |
263 | ||
264 | int | |
c58b9523 | 265 | bfd_seek (bfd *abfd, file_ptr position, int direction) |
93509525 KD |
266 | { |
267 | int result; | |
7c192733 | 268 | file_ptr file_position; |
93509525 KD |
269 | /* For the time being, a BFD may not seek to it's end. The problem |
270 | is that we don't easily have a way to recognize the end of an | |
271 | element in an archive. */ | |
272 | ||
273 | BFD_ASSERT (direction == SEEK_SET || direction == SEEK_CUR); | |
274 | ||
275 | if (direction == SEEK_CUR && position == 0) | |
276 | return 0; | |
277 | ||
278 | if ((abfd->flags & BFD_IN_MEMORY) != 0) | |
279 | { | |
280 | struct bfd_in_memory *bim; | |
281 | ||
c58b9523 | 282 | bim = abfd->iostream; |
93509525 KD |
283 | |
284 | if (direction == SEEK_SET) | |
285 | abfd->where = position; | |
286 | else | |
287 | abfd->where += position; | |
288 | ||
289 | if (abfd->where > bim->size) | |
290 | { | |
291 | if ((abfd->direction == write_direction) || | |
292 | (abfd->direction == both_direction)) | |
293 | { | |
294 | bfd_size_type newsize, oldsize; | |
69fd4758 | 295 | |
93509525 KD |
296 | oldsize = (bim->size + 127) & ~(bfd_size_type) 127; |
297 | bim->size = abfd->where; | |
298 | /* Round up to cut down on memory fragmentation */ | |
299 | newsize = (bim->size + 127) & ~(bfd_size_type) 127; | |
300 | if (newsize > oldsize) | |
301 | { | |
c58b9523 | 302 | bim->buffer = bfd_realloc (bim->buffer, newsize); |
93509525 KD |
303 | if (bim->buffer == 0) |
304 | { | |
305 | bim->size = 0; | |
306 | return -1; | |
307 | } | |
308 | } | |
309 | } | |
310 | else | |
311 | { | |
312 | abfd->where = bim->size; | |
313 | bfd_set_error (bfd_error_file_truncated); | |
314 | return -1; | |
315 | } | |
316 | } | |
317 | return 0; | |
318 | } | |
319 | ||
320 | if (abfd->format != bfd_archive && abfd->my_archive == 0) | |
321 | { | |
93509525 KD |
322 | if (direction == SEEK_SET && (bfd_vma) position == abfd->where) |
323 | return 0; | |
324 | } | |
325 | else | |
326 | { | |
327 | /* We need something smarter to optimize access to archives. | |
328 | Currently, anything inside an archive is read via the file | |
329 | handle for the archive. Which means that a bfd_seek on one | |
330 | component affects the `current position' in the archive, as | |
331 | well as in any other component. | |
332 | ||
333 | It might be sufficient to put a spike through the cache | |
334 | abstraction, and look to the archive for the file position, | |
335 | but I think we should try for something cleaner. | |
336 | ||
337 | In the meantime, no optimization for archives. */ | |
338 | } | |
339 | ||
93509525 KD |
340 | file_position = position; |
341 | if (direction == SEEK_SET && abfd->my_archive != NULL) | |
342 | file_position += abfd->origin; | |
343 | ||
69fd4758 NC |
344 | if (abfd->iovec) |
345 | result = abfd->iovec->bseek (abfd, file_position, direction); | |
346 | else | |
347 | result = -1; | |
348 | ||
93509525 KD |
349 | if (result != 0) |
350 | { | |
351 | int hold_errno = errno; | |
352 | ||
353 | /* Force redetermination of `where' field. */ | |
354 | bfd_tell (abfd); | |
355 | ||
356 | /* An EINVAL error probably means that the file offset was | |
357 | absurd. */ | |
358 | if (hold_errno == EINVAL) | |
359 | bfd_set_error (bfd_error_file_truncated); | |
360 | else | |
361 | { | |
362 | bfd_set_error (bfd_error_system_call); | |
363 | errno = hold_errno; | |
364 | } | |
365 | } | |
366 | else | |
367 | { | |
368 | /* Adjust `where' field. */ | |
369 | if (direction == SEEK_SET) | |
370 | abfd->where = position; | |
371 | else | |
372 | abfd->where += position; | |
373 | } | |
374 | return result; | |
375 | } | |
376 | ||
377 | /* | |
378 | FUNCTION | |
379 | bfd_get_mtime | |
380 | ||
381 | SYNOPSIS | |
c58b9523 | 382 | long bfd_get_mtime (bfd *abfd); |
93509525 KD |
383 | |
384 | DESCRIPTION | |
385 | Return the file modification time (as read from the file system, or | |
386 | from the archive header for archive members). | |
387 | ||
388 | */ | |
389 | ||
390 | long | |
c58b9523 | 391 | bfd_get_mtime (bfd *abfd) |
93509525 | 392 | { |
93509525 KD |
393 | struct stat buf; |
394 | ||
395 | if (abfd->mtime_set) | |
396 | return abfd->mtime; | |
397 | ||
69fd4758 NC |
398 | if (abfd->iovec == NULL) |
399 | return 0; | |
400 | ||
40838a72 | 401 | if (abfd->iovec->bstat (abfd, &buf) != 0) |
93509525 KD |
402 | return 0; |
403 | ||
404 | abfd->mtime = buf.st_mtime; /* Save value in case anyone wants it */ | |
405 | return buf.st_mtime; | |
406 | } | |
407 | ||
408 | /* | |
409 | FUNCTION | |
410 | bfd_get_size | |
411 | ||
412 | SYNOPSIS | |
74633dd0 | 413 | file_ptr bfd_get_size (bfd *abfd); |
93509525 KD |
414 | |
415 | DESCRIPTION | |
416 | Return the file size (as read from file system) for the file | |
417 | associated with BFD @var{abfd}. | |
418 | ||
419 | The initial motivation for, and use of, this routine is not | |
420 | so we can get the exact size of the object the BFD applies to, since | |
421 | that might not be generally possible (archive members for example). | |
422 | It would be ideal if someone could eventually modify | |
423 | it so that such results were guaranteed. | |
424 | ||
425 | Instead, we want to ask questions like "is this NNN byte sized | |
426 | object I'm about to try read from file offset YYY reasonable?" | |
427 | As as example of where we might do this, some object formats | |
428 | use string tables for which the first <<sizeof (long)>> bytes of the | |
429 | table contain the size of the table itself, including the size bytes. | |
430 | If an application tries to read what it thinks is one of these | |
431 | string tables, without some way to validate the size, and for | |
432 | some reason the size is wrong (byte swapping error, wrong location | |
433 | for the string table, etc.), the only clue is likely to be a read | |
434 | error when it tries to read the table, or a "virtual memory | |
435 | exhausted" error when it tries to allocate 15 bazillon bytes | |
436 | of space for the 15 bazillon byte table it is about to read. | |
5c4491d3 | 437 | This function at least allows us to answer the question, "is the |
93509525 KD |
438 | size reasonable?". |
439 | */ | |
440 | ||
74633dd0 | 441 | file_ptr |
c58b9523 | 442 | bfd_get_size (bfd *abfd) |
93509525 | 443 | { |
93509525 KD |
444 | struct stat buf; |
445 | ||
446 | if ((abfd->flags & BFD_IN_MEMORY) != 0) | |
447 | return ((struct bfd_in_memory *) abfd->iostream)->size; | |
448 | ||
69fd4758 NC |
449 | if (abfd->iovec == NULL) |
450 | return 0; | |
451 | ||
40838a72 | 452 | if (abfd->iovec->bstat (abfd, &buf) != 0) |
93509525 KD |
453 | return 0; |
454 | ||
455 | return buf.st_size; | |
456 | } |