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, | |
4 | 1999, 2000, 2001, 2002, 2003, 2004 Free Software Foundation, Inc. | |
5 | ||
93509525 KD |
6 | Written by Cygnus Support. |
7 | ||
8 | This file is part of BFD, the Binary File Descriptor library. | |
9 | ||
10 | This program is free software; you can redistribute it and/or modify | |
11 | it under the terms of the GNU General Public License as published by | |
12 | the Free Software Foundation; either version 2 of the License, or | |
13 | (at your option) any later version. | |
14 | ||
15 | This program is distributed in the hope that it will be useful, | |
16 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
17 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
18 | GNU General Public License for more details. | |
19 | ||
20 | You should have received a copy of the GNU General Public License | |
21 | along with this program; if not, write to the Free Software | |
22 | Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ | |
23 | ||
24 | #include "sysdep.h" | |
25 | ||
26 | #include "bfd.h" | |
27 | #include "libbfd.h" | |
28 | ||
29 | #include <limits.h> | |
30 | ||
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 | ||
40838a72 AC |
65 | /* |
66 | INTERNAL_DEFINITION | |
67 | struct bfd_iovec | |
93509525 | 68 | |
40838a72 | 69 | DESCRIPTION |
93509525 | 70 | |
40838a72 AC |
71 | The <<struct bfd_iovec>> contains the internal file I/O class. |
72 | Each <<BFD>> has an instance of this class and all file I/O is | |
73 | routed through it (it is assumed that the instance implements | |
74 | all methods listed below). | |
75 | ||
76 | .struct bfd_iovec | |
77 | .{ | |
78 | . {* To avoid problems with macros, a "b" rather than "f" | |
79 | . prefix is prepended to each method name. *} | |
80 | . {* Attempt to read/write NBYTES on ABFD's IOSTREAM storing/fetching | |
81 | . bytes starting at PTR. Return the number of bytes actually | |
82 | . transfered (a read past end-of-file returns less than NBYTES), | |
83 | . or -1 (setting <<bfd_error>>) if an error occurs. *} | |
84 | . file_ptr (*bread) (struct bfd *abfd, void *ptr, file_ptr nbytes); | |
85 | . file_ptr (*bwrite) (struct bfd *abfd, const void *ptr, | |
86 | . file_ptr nbytes); | |
87 | . {* Return the current IOSTREAM file offset, or -1 (setting <<bfd_error>> | |
88 | . if an error occurs. *} | |
89 | . file_ptr (*btell) (struct bfd *abfd); | |
90 | . {* For the following, on successful completion a value of 0 is returned. | |
91 | . Otherwise, a value of -1 is returned (and <<bfd_error>> is set). *} | |
92 | . int (*bseek) (struct bfd *abfd, file_ptr offset, int whence); | |
93 | . int (*bclose) (struct bfd *abfd); | |
94 | . int (*bflush) (struct bfd *abfd); | |
95 | . int (*bstat) (struct bfd *abfd, struct stat *sb); | |
96 | .}; | |
93509525 | 97 | |
40838a72 | 98 | */ |
93509525 | 99 | |
93509525 KD |
100 | |
101 | /* Return value is amount read. */ | |
102 | ||
103 | bfd_size_type | |
c58b9523 | 104 | bfd_bread (void *ptr, bfd_size_type size, bfd *abfd) |
93509525 KD |
105 | { |
106 | size_t nread; | |
107 | ||
108 | if ((abfd->flags & BFD_IN_MEMORY) != 0) | |
109 | { | |
110 | struct bfd_in_memory *bim; | |
111 | bfd_size_type get; | |
112 | ||
c58b9523 | 113 | bim = abfd->iostream; |
93509525 KD |
114 | get = size; |
115 | if (abfd->where + get > bim->size) | |
116 | { | |
117 | if (bim->size < (bfd_size_type) abfd->where) | |
118 | get = 0; | |
119 | else | |
120 | get = bim->size - abfd->where; | |
121 | bfd_set_error (bfd_error_file_truncated); | |
122 | } | |
123 | memcpy (ptr, bim->buffer + abfd->where, (size_t) get); | |
124 | abfd->where += get; | |
125 | return get; | |
126 | } | |
127 | ||
69fd4758 NC |
128 | if (abfd->iovec) |
129 | nread = abfd->iovec->bread (abfd, ptr, size); | |
130 | else | |
131 | nread = 0; | |
93509525 KD |
132 | if (nread != (size_t) -1) |
133 | abfd->where += nread; | |
134 | ||
93509525 KD |
135 | return nread; |
136 | } | |
137 | ||
138 | bfd_size_type | |
c58b9523 | 139 | bfd_bwrite (const void *ptr, bfd_size_type size, bfd *abfd) |
93509525 KD |
140 | { |
141 | size_t nwrote; | |
142 | ||
143 | if ((abfd->flags & BFD_IN_MEMORY) != 0) | |
144 | { | |
c58b9523 | 145 | struct bfd_in_memory *bim = abfd->iostream; |
69fd4758 | 146 | |
93509525 KD |
147 | size = (size_t) size; |
148 | if (abfd->where + size > bim->size) | |
149 | { | |
150 | bfd_size_type newsize, oldsize; | |
151 | ||
152 | oldsize = (bim->size + 127) & ~(bfd_size_type) 127; | |
153 | bim->size = abfd->where + size; | |
154 | /* Round up to cut down on memory fragmentation */ | |
155 | newsize = (bim->size + 127) & ~(bfd_size_type) 127; | |
156 | if (newsize > oldsize) | |
157 | { | |
c58b9523 | 158 | bim->buffer = bfd_realloc (bim->buffer, newsize); |
93509525 KD |
159 | if (bim->buffer == 0) |
160 | { | |
161 | bim->size = 0; | |
162 | return 0; | |
163 | } | |
164 | } | |
165 | } | |
166 | memcpy (bim->buffer + abfd->where, ptr, (size_t) size); | |
167 | abfd->where += size; | |
168 | return size; | |
169 | } | |
170 | ||
69fd4758 NC |
171 | if (abfd->iovec) |
172 | nwrote = abfd->iovec->bwrite (abfd, ptr, size); | |
173 | else | |
174 | nwrote = 0; | |
175 | ||
93509525 KD |
176 | if (nwrote != (size_t) -1) |
177 | abfd->where += nwrote; | |
178 | if (nwrote != size) | |
179 | { | |
180 | #ifdef ENOSPC | |
181 | errno = ENOSPC; | |
182 | #endif | |
183 | bfd_set_error (bfd_error_system_call); | |
184 | } | |
185 | return nwrote; | |
186 | } | |
187 | ||
7c192733 | 188 | file_ptr |
c58b9523 | 189 | bfd_tell (bfd *abfd) |
93509525 KD |
190 | { |
191 | file_ptr ptr; | |
192 | ||
193 | if ((abfd->flags & BFD_IN_MEMORY) != 0) | |
194 | return abfd->where; | |
195 | ||
69fd4758 NC |
196 | if (abfd->iovec) |
197 | { | |
198 | ptr = abfd->iovec->btell (abfd); | |
199 | ||
200 | if (abfd->my_archive) | |
201 | ptr -= abfd->origin; | |
202 | } | |
203 | else | |
204 | ptr = 0; | |
93509525 | 205 | |
93509525 KD |
206 | abfd->where = ptr; |
207 | return ptr; | |
208 | } | |
209 | ||
210 | int | |
c58b9523 | 211 | bfd_flush (bfd *abfd) |
93509525 KD |
212 | { |
213 | if ((abfd->flags & BFD_IN_MEMORY) != 0) | |
214 | return 0; | |
69fd4758 NC |
215 | |
216 | if (abfd->iovec) | |
217 | return abfd->iovec->bflush (abfd); | |
218 | return 0; | |
93509525 KD |
219 | } |
220 | ||
221 | /* Returns 0 for success, negative value for failure (in which case | |
222 | bfd_get_error can retrieve the error code). */ | |
223 | int | |
c58b9523 | 224 | bfd_stat (bfd *abfd, struct stat *statbuf) |
93509525 | 225 | { |
93509525 KD |
226 | int result; |
227 | ||
228 | if ((abfd->flags & BFD_IN_MEMORY) != 0) | |
229 | abort (); | |
230 | ||
69fd4758 NC |
231 | if (abfd->iovec) |
232 | result = abfd->iovec->bstat (abfd, statbuf); | |
233 | else | |
234 | result = -1; | |
235 | ||
93509525 KD |
236 | if (result < 0) |
237 | bfd_set_error (bfd_error_system_call); | |
238 | return result; | |
239 | } | |
240 | ||
241 | /* Returns 0 for success, nonzero for failure (in which case bfd_get_error | |
242 | can retrieve the error code). */ | |
243 | ||
244 | int | |
c58b9523 | 245 | bfd_seek (bfd *abfd, file_ptr position, int direction) |
93509525 KD |
246 | { |
247 | int result; | |
7c192733 | 248 | file_ptr file_position; |
93509525 KD |
249 | /* For the time being, a BFD may not seek to it's end. The problem |
250 | is that we don't easily have a way to recognize the end of an | |
251 | element in an archive. */ | |
252 | ||
253 | BFD_ASSERT (direction == SEEK_SET || direction == SEEK_CUR); | |
254 | ||
255 | if (direction == SEEK_CUR && position == 0) | |
256 | return 0; | |
257 | ||
258 | if ((abfd->flags & BFD_IN_MEMORY) != 0) | |
259 | { | |
260 | struct bfd_in_memory *bim; | |
261 | ||
c58b9523 | 262 | bim = abfd->iostream; |
93509525 KD |
263 | |
264 | if (direction == SEEK_SET) | |
265 | abfd->where = position; | |
266 | else | |
267 | abfd->where += position; | |
268 | ||
269 | if (abfd->where > bim->size) | |
270 | { | |
271 | if ((abfd->direction == write_direction) || | |
272 | (abfd->direction == both_direction)) | |
273 | { | |
274 | bfd_size_type newsize, oldsize; | |
69fd4758 | 275 | |
93509525 KD |
276 | oldsize = (bim->size + 127) & ~(bfd_size_type) 127; |
277 | bim->size = abfd->where; | |
278 | /* Round up to cut down on memory fragmentation */ | |
279 | newsize = (bim->size + 127) & ~(bfd_size_type) 127; | |
280 | if (newsize > oldsize) | |
281 | { | |
c58b9523 | 282 | bim->buffer = bfd_realloc (bim->buffer, newsize); |
93509525 KD |
283 | if (bim->buffer == 0) |
284 | { | |
285 | bim->size = 0; | |
286 | return -1; | |
287 | } | |
288 | } | |
289 | } | |
290 | else | |
291 | { | |
292 | abfd->where = bim->size; | |
293 | bfd_set_error (bfd_error_file_truncated); | |
294 | return -1; | |
295 | } | |
296 | } | |
297 | return 0; | |
298 | } | |
299 | ||
300 | if (abfd->format != bfd_archive && abfd->my_archive == 0) | |
301 | { | |
93509525 KD |
302 | if (direction == SEEK_SET && (bfd_vma) position == abfd->where) |
303 | return 0; | |
304 | } | |
305 | else | |
306 | { | |
307 | /* We need something smarter to optimize access to archives. | |
308 | Currently, anything inside an archive is read via the file | |
309 | handle for the archive. Which means that a bfd_seek on one | |
310 | component affects the `current position' in the archive, as | |
311 | well as in any other component. | |
312 | ||
313 | It might be sufficient to put a spike through the cache | |
314 | abstraction, and look to the archive for the file position, | |
315 | but I think we should try for something cleaner. | |
316 | ||
317 | In the meantime, no optimization for archives. */ | |
318 | } | |
319 | ||
93509525 KD |
320 | file_position = position; |
321 | if (direction == SEEK_SET && abfd->my_archive != NULL) | |
322 | file_position += abfd->origin; | |
323 | ||
69fd4758 NC |
324 | if (abfd->iovec) |
325 | result = abfd->iovec->bseek (abfd, file_position, direction); | |
326 | else | |
327 | result = -1; | |
328 | ||
93509525 KD |
329 | if (result != 0) |
330 | { | |
331 | int hold_errno = errno; | |
332 | ||
333 | /* Force redetermination of `where' field. */ | |
334 | bfd_tell (abfd); | |
335 | ||
336 | /* An EINVAL error probably means that the file offset was | |
337 | absurd. */ | |
338 | if (hold_errno == EINVAL) | |
339 | bfd_set_error (bfd_error_file_truncated); | |
340 | else | |
341 | { | |
342 | bfd_set_error (bfd_error_system_call); | |
343 | errno = hold_errno; | |
344 | } | |
345 | } | |
346 | else | |
347 | { | |
348 | /* Adjust `where' field. */ | |
349 | if (direction == SEEK_SET) | |
350 | abfd->where = position; | |
351 | else | |
352 | abfd->where += position; | |
353 | } | |
354 | return result; | |
355 | } | |
356 | ||
357 | /* | |
358 | FUNCTION | |
359 | bfd_get_mtime | |
360 | ||
361 | SYNOPSIS | |
c58b9523 | 362 | long bfd_get_mtime (bfd *abfd); |
93509525 KD |
363 | |
364 | DESCRIPTION | |
365 | Return the file modification time (as read from the file system, or | |
366 | from the archive header for archive members). | |
367 | ||
368 | */ | |
369 | ||
370 | long | |
c58b9523 | 371 | bfd_get_mtime (bfd *abfd) |
93509525 | 372 | { |
93509525 KD |
373 | struct stat buf; |
374 | ||
375 | if (abfd->mtime_set) | |
376 | return abfd->mtime; | |
377 | ||
69fd4758 NC |
378 | if (abfd->iovec == NULL) |
379 | return 0; | |
380 | ||
40838a72 | 381 | if (abfd->iovec->bstat (abfd, &buf) != 0) |
93509525 KD |
382 | return 0; |
383 | ||
384 | abfd->mtime = buf.st_mtime; /* Save value in case anyone wants it */ | |
385 | return buf.st_mtime; | |
386 | } | |
387 | ||
388 | /* | |
389 | FUNCTION | |
390 | bfd_get_size | |
391 | ||
392 | SYNOPSIS | |
c58b9523 | 393 | long bfd_get_size (bfd *abfd); |
93509525 KD |
394 | |
395 | DESCRIPTION | |
396 | Return the file size (as read from file system) for the file | |
397 | associated with BFD @var{abfd}. | |
398 | ||
399 | The initial motivation for, and use of, this routine is not | |
400 | so we can get the exact size of the object the BFD applies to, since | |
401 | that might not be generally possible (archive members for example). | |
402 | It would be ideal if someone could eventually modify | |
403 | it so that such results were guaranteed. | |
404 | ||
405 | Instead, we want to ask questions like "is this NNN byte sized | |
406 | object I'm about to try read from file offset YYY reasonable?" | |
407 | As as example of where we might do this, some object formats | |
408 | use string tables for which the first <<sizeof (long)>> bytes of the | |
409 | table contain the size of the table itself, including the size bytes. | |
410 | If an application tries to read what it thinks is one of these | |
411 | string tables, without some way to validate the size, and for | |
412 | some reason the size is wrong (byte swapping error, wrong location | |
413 | for the string table, etc.), the only clue is likely to be a read | |
414 | error when it tries to read the table, or a "virtual memory | |
415 | exhausted" error when it tries to allocate 15 bazillon bytes | |
416 | of space for the 15 bazillon byte table it is about to read. | |
5c4491d3 | 417 | This function at least allows us to answer the question, "is the |
93509525 KD |
418 | size reasonable?". |
419 | */ | |
420 | ||
421 | long | |
c58b9523 | 422 | bfd_get_size (bfd *abfd) |
93509525 | 423 | { |
93509525 KD |
424 | struct stat buf; |
425 | ||
426 | if ((abfd->flags & BFD_IN_MEMORY) != 0) | |
427 | return ((struct bfd_in_memory *) abfd->iostream)->size; | |
428 | ||
69fd4758 NC |
429 | if (abfd->iovec == NULL) |
430 | return 0; | |
431 | ||
40838a72 | 432 | if (abfd->iovec->bstat (abfd, &buf) != 0) |
93509525 KD |
433 | return 0; |
434 | ||
435 | return buf.st_size; | |
436 | } |