Commit | Line | Data |
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252b5132 | 1 | /* BFD library -- caching of file descriptors. |
7c192733 AC |
2 | |
3 | Copyright 1990, 1991, 1992, 1993, 1994, 1996, 2000, 2001, 2002, | |
aa820537 | 4 | 2003, 2004, 2005, 2007, 2008, 2009 Free Software Foundation, Inc. |
7c192733 | 5 | |
252b5132 RH |
6 | Hacked by Steve Chamberlain of Cygnus Support (steve@cygnus.com). |
7 | ||
cd123cb7 NC |
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 3 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., 51 Franklin Street - Fifth Floor, Boston, | |
23 | MA 02110-1301, USA. */ | |
252b5132 RH |
24 | |
25 | /* | |
26 | SECTION | |
27 | File caching | |
28 | ||
29 | The file caching mechanism is embedded within BFD and allows | |
30 | the application to open as many BFDs as it wants without | |
31 | regard to the underlying operating system's file descriptor | |
32 | limit (often as low as 20 open files). The module in | |
33 | <<cache.c>> maintains a least recently used list of | |
9d782e8d | 34 | <<bfd_cache_max_open>> files, and exports the name |
252b5132 RH |
35 | <<bfd_cache_lookup>>, which runs around and makes sure that |
36 | the required BFD is open. If not, then it chooses a file to | |
37 | close, closes it and opens the one wanted, returning its file | |
e60b52c6 | 38 | handle. |
252b5132 | 39 | |
1b74d094 BW |
40 | SUBSECTION |
41 | Caching functions | |
252b5132 RH |
42 | */ |
43 | ||
252b5132 | 44 | #include "sysdep.h" |
3db64b00 | 45 | #include "bfd.h" |
252b5132 | 46 | #include "libbfd.h" |
bb14f524 | 47 | #include "libiberty.h" |
4c95ab76 | 48 | #include "bfd_stdint.h" |
252b5132 | 49 | |
25b88f33 PP |
50 | #ifdef HAVE_MMAP |
51 | #include <sys/mman.h> | |
52 | #endif | |
53 | ||
95560129 AM |
54 | /* In some cases we can optimize cache operation when reopening files. |
55 | For instance, a flush is entirely unnecessary if the file is already | |
56 | closed, so a flush would use CACHE_NO_OPEN. Similarly, a seek using | |
57 | SEEK_SET or SEEK_END need not first seek to the current position. | |
58 | For stat we ignore seek errors, just in case the file has changed | |
59 | while we weren't looking. If it has, then it's possible that the | |
60 | file is shorter and we don't want a seek error to prevent us doing | |
61 | the stat. */ | |
62 | enum cache_flag { | |
63 | CACHE_NORMAL = 0, | |
64 | CACHE_NO_OPEN = 1, | |
65 | CACHE_NO_SEEK = 2, | |
66 | CACHE_NO_SEEK_ERROR = 4 | |
67 | }; | |
68 | ||
d00967c7 | 69 | /* The maximum number of files which the cache will keep open at |
9d782e8d | 70 | one time. When needed call bfd_cache_max_open to initialize. */ |
d0fdd288 | 71 | |
9d782e8d MW |
72 | static int max_open_files = 0; |
73 | ||
74 | /* Set max_open_files, if not already set, to 12.5% of the allowed open | |
75 | file descriptors, but at least 10, and return the value. */ | |
76 | static int | |
77 | bfd_cache_max_open (void) | |
78 | { | |
79 | if (max_open_files == 0) | |
80 | { | |
81 | int max; | |
82 | #ifdef HAVE_GETRLIMIT | |
83 | struct rlimit rlim; | |
84 | if (getrlimit (RLIMIT_NOFILE, &rlim) == 0 | |
85 | && rlim.rlim_cur != RLIM_INFINITY) | |
86 | max = rlim.rlim_cur / 8; | |
87 | else | |
88 | #endif /* HAVE_GETRLIMIT */ | |
89 | #ifdef _SC_OPEN_MAX | |
90 | max = sysconf (_SC_OPEN_MAX) / 8; | |
91 | #else | |
92 | max = 10; | |
93 | #endif /* _SC_OPEN_MAX */ | |
94 | max_open_files = max < 10 ? 10 : max; | |
95 | } | |
96 | ||
97 | return max_open_files; | |
98 | } | |
d0fdd288 AM |
99 | |
100 | /* The number of BFD files we have open. */ | |
101 | ||
102 | static int open_files; | |
103 | ||
d00967c7 AM |
104 | /* Zero, or a pointer to the topmost BFD on the chain. This is |
105 | used by the <<bfd_cache_lookup>> macro in @file{libbfd.h} to | |
106 | determine when it can avoid a function call. */ | |
d0fdd288 | 107 | |
d00967c7 | 108 | static bfd *bfd_last_cache = NULL; |
252b5132 | 109 | |
d0fdd288 AM |
110 | /* Insert a BFD into the cache. */ |
111 | ||
112 | static void | |
113 | insert (bfd *abfd) | |
114 | { | |
115 | if (bfd_last_cache == NULL) | |
116 | { | |
117 | abfd->lru_next = abfd; | |
118 | abfd->lru_prev = abfd; | |
119 | } | |
120 | else | |
121 | { | |
122 | abfd->lru_next = bfd_last_cache; | |
123 | abfd->lru_prev = bfd_last_cache->lru_prev; | |
124 | abfd->lru_prev->lru_next = abfd; | |
125 | abfd->lru_next->lru_prev = abfd; | |
126 | } | |
127 | bfd_last_cache = abfd; | |
128 | } | |
129 | ||
130 | /* Remove a BFD from the cache. */ | |
131 | ||
132 | static void | |
133 | snip (bfd *abfd) | |
134 | { | |
135 | abfd->lru_prev->lru_next = abfd->lru_next; | |
136 | abfd->lru_next->lru_prev = abfd->lru_prev; | |
137 | if (abfd == bfd_last_cache) | |
138 | { | |
139 | bfd_last_cache = abfd->lru_next; | |
140 | if (abfd == bfd_last_cache) | |
141 | bfd_last_cache = NULL; | |
142 | } | |
143 | } | |
144 | ||
145 | /* Close a BFD and remove it from the cache. */ | |
146 | ||
147 | static bfd_boolean | |
148 | bfd_cache_delete (bfd *abfd) | |
149 | { | |
150 | bfd_boolean ret; | |
151 | ||
152 | if (fclose ((FILE *) abfd->iostream) == 0) | |
153 | ret = TRUE; | |
154 | else | |
155 | { | |
156 | ret = FALSE; | |
157 | bfd_set_error (bfd_error_system_call); | |
158 | } | |
159 | ||
160 | snip (abfd); | |
161 | ||
162 | abfd->iostream = NULL; | |
163 | --open_files; | |
164 | ||
165 | return ret; | |
166 | } | |
167 | ||
168 | /* We need to open a new file, and the cache is full. Find the least | |
169 | recently used cacheable BFD and close it. */ | |
170 | ||
171 | static bfd_boolean | |
172 | close_one (void) | |
173 | { | |
f664f618 | 174 | register bfd *to_kill; |
d0fdd288 AM |
175 | |
176 | if (bfd_last_cache == NULL) | |
f664f618 | 177 | to_kill = NULL; |
d0fdd288 AM |
178 | else |
179 | { | |
f664f618 TG |
180 | for (to_kill = bfd_last_cache->lru_prev; |
181 | ! to_kill->cacheable; | |
182 | to_kill = to_kill->lru_prev) | |
d0fdd288 | 183 | { |
f664f618 | 184 | if (to_kill == bfd_last_cache) |
d0fdd288 | 185 | { |
f664f618 | 186 | to_kill = NULL; |
d0fdd288 AM |
187 | break; |
188 | } | |
189 | } | |
190 | } | |
191 | ||
f664f618 | 192 | if (to_kill == NULL) |
d0fdd288 AM |
193 | { |
194 | /* There are no open cacheable BFD's. */ | |
195 | return TRUE; | |
196 | } | |
197 | ||
f664f618 | 198 | to_kill->where = real_ftell ((FILE *) to_kill->iostream); |
d0fdd288 | 199 | |
f664f618 | 200 | return bfd_cache_delete (to_kill); |
d0fdd288 AM |
201 | } |
202 | ||
d00967c7 AM |
203 | /* Check to see if the required BFD is the same as the last one |
204 | looked up. If so, then it can use the stream in the BFD with | |
205 | impunity, since it can't have changed since the last lookup; | |
206 | otherwise, it has to perform the complicated lookup function. */ | |
d0fdd288 | 207 | |
95560129 | 208 | #define bfd_cache_lookup(x, flag) \ |
d00967c7 AM |
209 | ((x) == bfd_last_cache \ |
210 | ? (FILE *) (bfd_last_cache->iostream) \ | |
95560129 | 211 | : bfd_cache_lookup_worker (x, flag)) |
d0fdd288 | 212 | |
d00967c7 AM |
213 | /* Called when the macro <<bfd_cache_lookup>> fails to find a |
214 | quick answer. Find a file descriptor for @var{abfd}. If | |
215 | necessary, it open it. If there are already more than | |
9d782e8d | 216 | <<bfd_cache_max_open>> files open, it tries to close one first, to |
d00967c7 AM |
217 | avoid running out of file descriptors. It will return NULL |
218 | if it is unable to (re)open the @var{abfd}. */ | |
d0fdd288 | 219 | |
d00967c7 | 220 | static FILE * |
95560129 | 221 | bfd_cache_lookup_worker (bfd *abfd, enum cache_flag flag) |
d0fdd288 AM |
222 | { |
223 | bfd *orig_bfd = abfd; | |
224 | if ((abfd->flags & BFD_IN_MEMORY) != 0) | |
225 | abort (); | |
226 | ||
660722b0 | 227 | while (abfd->my_archive) |
d0fdd288 AM |
228 | abfd = abfd->my_archive; |
229 | ||
230 | if (abfd->iostream != NULL) | |
231 | { | |
232 | /* Move the file to the start of the cache. */ | |
233 | if (abfd != bfd_last_cache) | |
234 | { | |
235 | snip (abfd); | |
236 | insert (abfd); | |
237 | } | |
238 | return (FILE *) abfd->iostream; | |
239 | } | |
240 | ||
95560129 AM |
241 | if (flag & CACHE_NO_OPEN) |
242 | return NULL; | |
243 | ||
d0fdd288 AM |
244 | if (bfd_open_file (abfd) == NULL) |
245 | ; | |
95560129 AM |
246 | else if (!(flag & CACHE_NO_SEEK) |
247 | && real_fseek ((FILE *) abfd->iostream, abfd->where, SEEK_SET) != 0 | |
248 | && !(flag & CACHE_NO_SEEK_ERROR)) | |
d0fdd288 AM |
249 | bfd_set_error (bfd_error_system_call); |
250 | else | |
251 | return (FILE *) abfd->iostream; | |
252 | ||
253 | (*_bfd_error_handler) (_("reopening %B: %s\n"), | |
254 | orig_bfd, bfd_errmsg (bfd_get_error ())); | |
255 | return NULL; | |
256 | } | |
40838a72 AC |
257 | |
258 | static file_ptr | |
259 | cache_btell (struct bfd *abfd) | |
260 | { | |
95560129 | 261 | FILE *f = bfd_cache_lookup (abfd, CACHE_NO_OPEN); |
3dff57e8 | 262 | if (f == NULL) |
95560129 | 263 | return abfd->where; |
3dff57e8 | 264 | return real_ftell (f); |
40838a72 AC |
265 | } |
266 | ||
267 | static int | |
268 | cache_bseek (struct bfd *abfd, file_ptr offset, int whence) | |
269 | { | |
a50b1753 | 270 | FILE *f = bfd_cache_lookup (abfd, whence != SEEK_CUR ? CACHE_NO_SEEK : CACHE_NORMAL); |
3dff57e8 AM |
271 | if (f == NULL) |
272 | return -1; | |
273 | return real_fseek (f, offset, whence); | |
40838a72 AC |
274 | } |
275 | ||
276 | /* Note that archive entries don't have streams; they share their parent's. | |
277 | This allows someone to play with the iostream behind BFD's back. | |
278 | ||
279 | Also, note that the origin pointer points to the beginning of a file's | |
280 | contents (0 for non-archive elements). For archive entries this is the | |
281 | first octet in the file, NOT the beginning of the archive header. */ | |
282 | ||
283 | static file_ptr | |
f12a02c0 | 284 | cache_bread_1 (struct bfd *abfd, void *buf, file_ptr nbytes) |
40838a72 | 285 | { |
3dff57e8 | 286 | FILE *f; |
40838a72 AC |
287 | file_ptr nread; |
288 | /* FIXME - this looks like an optimization, but it's really to cover | |
289 | up for a feature of some OSs (not solaris - sigh) that | |
290 | ld/pe-dll.c takes advantage of (apparently) when it creates BFDs | |
291 | internally and tries to link against them. BFD seems to be smart | |
292 | enough to realize there are no symbol records in the "file" that | |
293 | doesn't exist but attempts to read them anyway. On Solaris, | |
294 | attempting to read zero bytes from a NULL file results in a core | |
295 | dump, but on other platforms it just returns zero bytes read. | |
296 | This makes it to something reasonable. - DJ */ | |
297 | if (nbytes == 0) | |
298 | return 0; | |
299 | ||
a50b1753 | 300 | f = bfd_cache_lookup (abfd, CACHE_NORMAL); |
3dff57e8 AM |
301 | if (f == NULL) |
302 | return 0; | |
303 | ||
40838a72 AC |
304 | #if defined (__VAX) && defined (VMS) |
305 | /* Apparently fread on Vax VMS does not keep the record length | |
306 | information. */ | |
3dff57e8 | 307 | nread = read (fileno (f), buf, nbytes); |
40838a72 AC |
308 | /* Set bfd_error if we did not read as much data as we expected. If |
309 | the read failed due to an error set the bfd_error_system_call, | |
310 | else set bfd_error_file_truncated. */ | |
311 | if (nread == (file_ptr)-1) | |
312 | { | |
313 | bfd_set_error (bfd_error_system_call); | |
314 | return -1; | |
315 | } | |
316 | #else | |
3dff57e8 | 317 | nread = fread (buf, 1, nbytes, f); |
40838a72 AC |
318 | /* Set bfd_error if we did not read as much data as we expected. If |
319 | the read failed due to an error set the bfd_error_system_call, | |
320 | else set bfd_error_file_truncated. */ | |
3dff57e8 | 321 | if (nread < nbytes && ferror (f)) |
40838a72 AC |
322 | { |
323 | bfd_set_error (bfd_error_system_call); | |
324 | return -1; | |
325 | } | |
326 | #endif | |
662ed161 DJ |
327 | if (nread < nbytes) |
328 | /* This may or may not be an error, but in case the calling code | |
329 | bails out because of it, set the right error code. */ | |
330 | bfd_set_error (bfd_error_file_truncated); | |
40838a72 AC |
331 | return nread; |
332 | } | |
333 | ||
f12a02c0 JB |
334 | static file_ptr |
335 | cache_bread (struct bfd *abfd, void *buf, file_ptr nbytes) | |
336 | { | |
337 | file_ptr nread = 0; | |
338 | ||
339 | /* Some filesystems are unable to handle reads that are too large | |
340 | (for instance, NetApp shares with oplocks turned off). To avoid | |
341 | hitting this limitation, we read the buffer in chunks of 8MB max. */ | |
342 | while (nread < nbytes) | |
343 | { | |
344 | const file_ptr max_chunk_size = 0x800000; | |
345 | file_ptr chunk_size = nbytes - nread; | |
346 | file_ptr chunk_nread; | |
347 | ||
348 | if (chunk_size > max_chunk_size) | |
349 | chunk_size = max_chunk_size; | |
350 | ||
cb5220a0 | 351 | chunk_nread = cache_bread_1 (abfd, (char *) buf + nread, chunk_size); |
f12a02c0 JB |
352 | |
353 | /* Update the nread count. | |
354 | ||
355 | We just have to be careful of the case when cache_bread_1 returns | |
356 | a negative count: If this is our first read, then set nread to | |
357 | that negative count in order to return that negative value to the | |
358 | caller. Otherwise, don't add it to our total count, or we would | |
359 | end up returning a smaller number of bytes read than we actually | |
360 | did. */ | |
361 | if (nread == 0 || chunk_nread > 0) | |
362 | nread += chunk_nread; | |
363 | ||
364 | if (chunk_nread < chunk_size) | |
365 | break; | |
366 | } | |
367 | ||
368 | return nread; | |
369 | } | |
370 | ||
40838a72 AC |
371 | static file_ptr |
372 | cache_bwrite (struct bfd *abfd, const void *where, file_ptr nbytes) | |
373 | { | |
3dff57e8 | 374 | file_ptr nwrite; |
a50b1753 | 375 | FILE *f = bfd_cache_lookup (abfd, CACHE_NORMAL); |
cb5220a0 | 376 | |
3dff57e8 AM |
377 | if (f == NULL) |
378 | return 0; | |
379 | nwrite = fwrite (where, 1, nbytes, f); | |
380 | if (nwrite < nbytes && ferror (f)) | |
40838a72 AC |
381 | { |
382 | bfd_set_error (bfd_error_system_call); | |
383 | return -1; | |
384 | } | |
385 | return nwrite; | |
386 | } | |
387 | ||
405bf443 | 388 | static int |
40838a72 AC |
389 | cache_bclose (struct bfd *abfd) |
390 | { | |
405bf443 | 391 | return bfd_cache_close (abfd) - 1; |
40838a72 AC |
392 | } |
393 | ||
394 | static int | |
395 | cache_bflush (struct bfd *abfd) | |
396 | { | |
3dff57e8 | 397 | int sts; |
95560129 | 398 | FILE *f = bfd_cache_lookup (abfd, CACHE_NO_OPEN); |
cb5220a0 | 399 | |
3dff57e8 | 400 | if (f == NULL) |
95560129 | 401 | return 0; |
3dff57e8 | 402 | sts = fflush (f); |
40838a72 AC |
403 | if (sts < 0) |
404 | bfd_set_error (bfd_error_system_call); | |
405 | return sts; | |
406 | } | |
407 | ||
408 | static int | |
409 | cache_bstat (struct bfd *abfd, struct stat *sb) | |
410 | { | |
3dff57e8 | 411 | int sts; |
95560129 | 412 | FILE *f = bfd_cache_lookup (abfd, CACHE_NO_SEEK_ERROR); |
cb5220a0 | 413 | |
3dff57e8 AM |
414 | if (f == NULL) |
415 | return -1; | |
416 | sts = fstat (fileno (f), sb); | |
40838a72 AC |
417 | if (sts < 0) |
418 | bfd_set_error (bfd_error_system_call); | |
419 | return sts; | |
420 | } | |
421 | ||
25b88f33 PP |
422 | static void * |
423 | cache_bmmap (struct bfd *abfd ATTRIBUTE_UNUSED, | |
424 | void *addr ATTRIBUTE_UNUSED, | |
425 | bfd_size_type len ATTRIBUTE_UNUSED, | |
426 | int prot ATTRIBUTE_UNUSED, | |
427 | int flags ATTRIBUTE_UNUSED, | |
4c95ab76 TG |
428 | file_ptr offset ATTRIBUTE_UNUSED, |
429 | void **map_addr ATTRIBUTE_UNUSED, | |
430 | bfd_size_type *map_len ATTRIBUTE_UNUSED) | |
25b88f33 PP |
431 | { |
432 | void *ret = (void *) -1; | |
433 | ||
434 | if ((abfd->flags & BFD_IN_MEMORY) != 0) | |
435 | abort (); | |
436 | #ifdef HAVE_MMAP | |
437 | else | |
438 | { | |
4c95ab76 TG |
439 | static uintptr_t pagesize_m1; |
440 | FILE *f; | |
441 | file_ptr pg_offset; | |
442 | bfd_size_type pg_len; | |
443 | ||
444 | f = bfd_cache_lookup (abfd, CACHE_NO_SEEK_ERROR); | |
25b88f33 PP |
445 | if (f == NULL) |
446 | return ret; | |
447 | ||
4c95ab76 TG |
448 | if (pagesize_m1 == 0) |
449 | pagesize_m1 = getpagesize () - 1; | |
450 | ||
451 | /* Handle archive members. */ | |
452 | if (abfd->my_archive != NULL) | |
453 | offset += abfd->origin; | |
454 | ||
455 | /* Align. */ | |
456 | pg_offset = offset & ~pagesize_m1; | |
457 | pg_len = (len + (offset - pg_offset) + pagesize_m1) & ~pagesize_m1; | |
458 | ||
459 | ret = mmap (addr, pg_len, prot, flags, fileno (f), pg_offset); | |
25b88f33 PP |
460 | if (ret == (void *) -1) |
461 | bfd_set_error (bfd_error_system_call); | |
4c95ab76 TG |
462 | else |
463 | { | |
464 | *map_addr = ret; | |
465 | *map_len = pg_len; | |
eac3aa9e | 466 | ret = (char *) ret + (offset & pagesize_m1); |
4c95ab76 | 467 | } |
25b88f33 PP |
468 | } |
469 | #endif | |
470 | ||
471 | return ret; | |
472 | } | |
473 | ||
cb5220a0 NC |
474 | static const struct bfd_iovec cache_iovec = |
475 | { | |
40838a72 | 476 | &cache_bread, &cache_bwrite, &cache_btell, &cache_bseek, |
25b88f33 | 477 | &cache_bclose, &cache_bflush, &cache_bstat, &cache_bmmap |
40838a72 AC |
478 | }; |
479 | ||
252b5132 RH |
480 | /* |
481 | INTERNAL_FUNCTION | |
482 | bfd_cache_init | |
483 | ||
484 | SYNOPSIS | |
b34976b6 | 485 | bfd_boolean bfd_cache_init (bfd *abfd); |
252b5132 RH |
486 | |
487 | DESCRIPTION | |
488 | Add a newly opened BFD to the cache. | |
489 | */ | |
490 | ||
b34976b6 | 491 | bfd_boolean |
c58b9523 | 492 | bfd_cache_init (bfd *abfd) |
252b5132 RH |
493 | { |
494 | BFD_ASSERT (abfd->iostream != NULL); | |
9d782e8d | 495 | if (open_files >= bfd_cache_max_open ()) |
252b5132 RH |
496 | { |
497 | if (! close_one ()) | |
b34976b6 | 498 | return FALSE; |
252b5132 | 499 | } |
40838a72 | 500 | abfd->iovec = &cache_iovec; |
252b5132 RH |
501 | insert (abfd); |
502 | ++open_files; | |
b34976b6 | 503 | return TRUE; |
252b5132 RH |
504 | } |
505 | ||
506 | /* | |
507 | INTERNAL_FUNCTION | |
508 | bfd_cache_close | |
509 | ||
510 | SYNOPSIS | |
b34976b6 | 511 | bfd_boolean bfd_cache_close (bfd *abfd); |
252b5132 RH |
512 | |
513 | DESCRIPTION | |
514 | Remove the BFD @var{abfd} from the cache. If the attached file is open, | |
515 | then close it too. | |
516 | ||
517 | RETURNS | |
b34976b6 | 518 | <<FALSE>> is returned if closing the file fails, <<TRUE>> is |
252b5132 RH |
519 | returned if all is well. |
520 | */ | |
521 | ||
b34976b6 | 522 | bfd_boolean |
c58b9523 | 523 | bfd_cache_close (bfd *abfd) |
252b5132 | 524 | { |
40838a72 | 525 | if (abfd->iovec != &cache_iovec) |
b34976b6 | 526 | return TRUE; |
252b5132 | 527 | |
fe2e161a AC |
528 | if (abfd->iostream == NULL) |
529 | /* Previously closed. */ | |
530 | return TRUE; | |
531 | ||
252b5132 RH |
532 | return bfd_cache_delete (abfd); |
533 | } | |
534 | ||
02d5a37b JG |
535 | /* |
536 | FUNCTION | |
537 | bfd_cache_close_all | |
538 | ||
539 | SYNOPSIS | |
540 | bfd_boolean bfd_cache_close_all (void); | |
541 | ||
542 | DESCRIPTION | |
543 | Remove all BFDs from the cache. If the attached file is open, | |
544 | then close it too. | |
545 | ||
546 | RETURNS | |
547 | <<FALSE>> is returned if closing one of the file fails, <<TRUE>> is | |
548 | returned if all is well. | |
549 | */ | |
550 | ||
551 | bfd_boolean | |
552 | bfd_cache_close_all () | |
553 | { | |
554 | bfd_boolean ret = TRUE; | |
555 | ||
556 | while (bfd_last_cache != NULL) | |
557 | ret &= bfd_cache_close (bfd_last_cache); | |
c9b549b2 JG |
558 | |
559 | return ret; | |
02d5a37b JG |
560 | } |
561 | ||
252b5132 RH |
562 | /* |
563 | INTERNAL_FUNCTION | |
564 | bfd_open_file | |
565 | ||
566 | SYNOPSIS | |
c58b9523 | 567 | FILE* bfd_open_file (bfd *abfd); |
252b5132 RH |
568 | |
569 | DESCRIPTION | |
570 | Call the OS to open a file for @var{abfd}. Return the <<FILE *>> | |
571 | (possibly <<NULL>>) that results from this operation. Set up the | |
572 | BFD so that future accesses know the file is open. If the <<FILE *>> | |
573 | returned is <<NULL>>, then it won't have been put in the | |
574 | cache, so it won't have to be removed from it. | |
575 | */ | |
576 | ||
577 | FILE * | |
c58b9523 | 578 | bfd_open_file (bfd *abfd) |
252b5132 | 579 | { |
b34976b6 | 580 | abfd->cacheable = TRUE; /* Allow it to be closed later. */ |
252b5132 | 581 | |
9d782e8d | 582 | if (open_files >= bfd_cache_max_open ()) |
252b5132 RH |
583 | { |
584 | if (! close_one ()) | |
585 | return NULL; | |
586 | } | |
587 | ||
588 | switch (abfd->direction) | |
589 | { | |
590 | case read_direction: | |
591 | case no_direction: | |
2c3fc389 | 592 | abfd->iostream = real_fopen (abfd->filename, FOPEN_RB); |
252b5132 RH |
593 | break; |
594 | case both_direction: | |
595 | case write_direction: | |
82e51918 | 596 | if (abfd->opened_once) |
252b5132 | 597 | { |
2c3fc389 | 598 | abfd->iostream = real_fopen (abfd->filename, FOPEN_RUB); |
252b5132 | 599 | if (abfd->iostream == NULL) |
2c3fc389 | 600 | abfd->iostream = real_fopen (abfd->filename, FOPEN_WUB); |
252b5132 RH |
601 | } |
602 | else | |
603 | { | |
9e422a2e ILT |
604 | /* Create the file. |
605 | ||
606 | Some operating systems won't let us overwrite a running | |
607 | binary. For them, we want to unlink the file first. | |
608 | ||
609 | However, gcc 2.95 will create temporary files using | |
610 | O_EXCL and tight permissions to prevent other users from | |
611 | substituting other .o files during the compilation. gcc | |
612 | will then tell the assembler to use the newly created | |
613 | file as an output file. If we unlink the file here, we | |
614 | open a brief window when another user could still | |
615 | substitute a file. | |
616 | ||
617 | So we unlink the output file if and only if it has | |
618 | non-zero size. */ | |
5af11cab AM |
619 | #ifndef __MSDOS__ |
620 | /* Don't do this for MSDOS: it doesn't care about overwriting | |
621 | a running binary, but if this file is already open by | |
622 | another BFD, we will be in deep trouble if we delete an | |
623 | open file. In fact, objdump does just that if invoked with | |
624 | the --info option. */ | |
9e422a2e ILT |
625 | struct stat s; |
626 | ||
627 | if (stat (abfd->filename, &s) == 0 && s.st_size != 0) | |
bb14f524 | 628 | unlink_if_ordinary (abfd->filename); |
5af11cab | 629 | #endif |
2c3fc389 | 630 | abfd->iostream = real_fopen (abfd->filename, FOPEN_WUB); |
b34976b6 | 631 | abfd->opened_once = TRUE; |
252b5132 RH |
632 | } |
633 | break; | |
634 | } | |
635 | ||
5c91cdfb AM |
636 | if (abfd->iostream == NULL) |
637 | bfd_set_error (bfd_error_system_call); | |
638 | else | |
252b5132 RH |
639 | { |
640 | if (! bfd_cache_init (abfd)) | |
641 | return NULL; | |
642 | } | |
643 | ||
644 | return (FILE *) abfd->iostream; | |
645 | } |