1 /* Low-level I/O routines for BFDs.
3 Copyright (C) 1990-2020 Free Software Foundation, Inc.
5 Written by Cygnus Support.
7 This file is part of BFD, the Binary File Descriptor library.
9 This program is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 3 of the License, or
12 (at your option) any later version.
14 This program is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
19 You should have received a copy of the GNU General Public License
20 along with this program; if not, write to the Free Software
21 Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
22 MA 02110-1301, USA. */
34 #define S_IXUSR 0100 /* Execute by owner. */
37 #define S_IXGRP 0010 /* Execute by group. */
40 #define S_IXOTH 0001 /* Execute by others. */
48 _bfd_real_ftell (FILE *file
)
50 #if defined (HAVE_FTELLO64)
51 return ftello64 (file
);
52 #elif defined (HAVE_FTELLO)
60 _bfd_real_fseek (FILE *file
, file_ptr offset
, int whence
)
62 #if defined (HAVE_FSEEKO64)
63 return fseeko64 (file
, offset
, whence
);
64 #elif defined (HAVE_FSEEKO)
65 return fseeko (file
, offset
, whence
);
67 return fseek (file
, offset
, whence
);
71 /* Mark FILE as close-on-exec. Return FILE. FILE may be NULL, in
72 which case nothing is done. */
74 close_on_exec (FILE *file
)
76 #if defined (HAVE_FILENO) && defined (F_GETFD)
79 int fd
= fileno (file
);
80 int old
= fcntl (fd
, F_GETFD
, 0);
82 fcntl (fd
, F_SETFD
, old
| FD_CLOEXEC
);
89 _bfd_real_fopen (const char *filename
, const char *modes
)
94 /* On VMS, fopen allows file attributes as optional arguments.
95 We need to use them but we'd better to use the common prototype.
96 In fopen-vms.h, they are separated from the mode with a comma.
98 vms_attr
= strchr (modes
, ',');
101 /* Attributes found. Split. */
102 size_t modes_len
= strlen (modes
) + 1;
103 char attrs
[modes_len
+ 1];
107 memcpy (attrs
, modes
, modes_len
);
109 for (i
= 0; i
< 2; i
++)
111 at
[i
+ 1] = strchr (at
[i
], ',');
112 BFD_ASSERT (at
[i
+ 1] != NULL
);
113 *(at
[i
+ 1]++) = 0; /* Replace ',' with a nul, and skip it. */
115 return close_on_exec (fopen (filename
, at
[0], at
[1], at
[2]));
118 #elif defined (_WIN32)
119 size_t filelen
= strlen (filename
) + 1;
121 if (filelen
> MAX_PATH
- 1)
124 char* fullpath
= (char *) malloc (filelen
+ 8);
126 /* Add a Microsoft recommended prefix that
127 will allow the extra-long path to work. */
128 strcpy (fullpath
, "\\\\?\\");
129 strcat (fullpath
, filename
);
130 file
= close_on_exec (fopen (fullpath
, modes
));
135 #elif defined (HAVE_FOPEN64)
136 return close_on_exec (fopen64 (filename
, modes
));
139 return close_on_exec (fopen (filename
, modes
));
148 The <<struct bfd_iovec>> contains the internal file I/O class.
149 Each <<BFD>> has an instance of this class and all file I/O is
150 routed through it (it is assumed that the instance implements
151 all methods listed below).
155 . {* To avoid problems with macros, a "b" rather than "f"
156 . prefix is prepended to each method name. *}
157 . {* Attempt to read/write NBYTES on ABFD's IOSTREAM storing/fetching
158 . bytes starting at PTR. Return the number of bytes actually
159 . transfered (a read past end-of-file returns less than NBYTES),
160 . or -1 (setting <<bfd_error>>) if an error occurs. *}
161 . file_ptr (*bread) (struct bfd *abfd, void *ptr, file_ptr nbytes);
162 . file_ptr (*bwrite) (struct bfd *abfd, const void *ptr,
164 . {* Return the current IOSTREAM file offset, or -1 (setting <<bfd_error>>
165 . if an error occurs. *}
166 . file_ptr (*btell) (struct bfd *abfd);
167 . {* For the following, on successful completion a value of 0 is returned.
168 . Otherwise, a value of -1 is returned (and <<bfd_error>> is set). *}
169 . int (*bseek) (struct bfd *abfd, file_ptr offset, int whence);
170 . int (*bclose) (struct bfd *abfd);
171 . int (*bflush) (struct bfd *abfd);
172 . int (*bstat) (struct bfd *abfd, struct stat *sb);
173 . {* Mmap a part of the files. ADDR, LEN, PROT, FLAGS and OFFSET are the usual
174 . mmap parameter, except that LEN and OFFSET do not need to be page
175 . aligned. Returns (void *)-1 on failure, mmapped address on success.
176 . Also write in MAP_ADDR the address of the page aligned buffer and in
177 . MAP_LEN the size mapped (a page multiple). Use unmap with MAP_ADDR and
178 . MAP_LEN to unmap. *}
179 . void *(*bmmap) (struct bfd *abfd, void *addr, bfd_size_type len,
180 . int prot, int flags, file_ptr offset,
181 . void **map_addr, bfd_size_type *map_len);
184 .extern const struct bfd_iovec _bfd_memory_iovec;
189 /* Return value is amount read. */
192 bfd_bread (void *ptr
, bfd_size_type size
, bfd
*abfd
)
195 bfd
*element_bfd
= abfd
;
196 ufile_ptr offset
= 0;
198 while (abfd
->my_archive
!= NULL
199 && !bfd_is_thin_archive (abfd
->my_archive
))
201 offset
+= abfd
->origin
;
202 abfd
= abfd
->my_archive
;
205 /* If this is an archive element, don't read past the end of
207 if (element_bfd
->arelt_data
!= NULL
)
209 bfd_size_type maxbytes
= arelt_size (element_bfd
);
211 if (abfd
->where
< offset
|| abfd
->where
- offset
>= maxbytes
)
213 bfd_set_error (bfd_error_invalid_operation
);
216 if (abfd
->where
- offset
+ size
> maxbytes
)
217 size
= maxbytes
- (abfd
->where
- offset
);
220 if (abfd
->iovec
== NULL
)
222 bfd_set_error (bfd_error_invalid_operation
);
226 nread
= abfd
->iovec
->bread (abfd
, ptr
, size
);
228 abfd
->where
+= nread
;
234 bfd_bwrite (const void *ptr
, bfd_size_type size
, bfd
*abfd
)
238 while (abfd
->my_archive
!= NULL
239 && !bfd_is_thin_archive (abfd
->my_archive
))
240 abfd
= abfd
->my_archive
;
242 if (abfd
->iovec
== NULL
)
244 bfd_set_error (bfd_error_invalid_operation
);
248 nwrote
= abfd
->iovec
->bwrite (abfd
, ptr
, size
);
250 abfd
->where
+= nwrote
;
251 if ((bfd_size_type
) nwrote
!= size
)
256 bfd_set_error (bfd_error_system_call
);
264 ufile_ptr offset
= 0;
267 while (abfd
->my_archive
!= NULL
268 && !bfd_is_thin_archive (abfd
->my_archive
))
270 offset
+= abfd
->origin
;
271 abfd
= abfd
->my_archive
;
274 if (abfd
->iovec
== NULL
)
277 ptr
= abfd
->iovec
->btell (abfd
);
283 bfd_flush (bfd
*abfd
)
285 while (abfd
->my_archive
!= NULL
286 && !bfd_is_thin_archive (abfd
->my_archive
))
287 abfd
= abfd
->my_archive
;
289 if (abfd
->iovec
== NULL
)
292 return abfd
->iovec
->bflush (abfd
);
295 /* Returns 0 for success, negative value for failure (in which case
296 bfd_get_error can retrieve the error code). */
298 bfd_stat (bfd
*abfd
, struct stat
*statbuf
)
302 while (abfd
->my_archive
!= NULL
303 && !bfd_is_thin_archive (abfd
->my_archive
))
304 abfd
= abfd
->my_archive
;
306 if (abfd
->iovec
== NULL
)
308 bfd_set_error (bfd_error_invalid_operation
);
312 result
= abfd
->iovec
->bstat (abfd
, statbuf
);
314 bfd_set_error (bfd_error_system_call
);
318 /* Returns 0 for success, nonzero for failure (in which case bfd_get_error
319 can retrieve the error code). */
322 bfd_seek (bfd
*abfd
, file_ptr position
, int direction
)
325 ufile_ptr offset
= 0;
327 while (abfd
->my_archive
!= NULL
328 && !bfd_is_thin_archive (abfd
->my_archive
))
330 offset
+= abfd
->origin
;
331 abfd
= abfd
->my_archive
;
334 if (abfd
->iovec
== NULL
)
336 bfd_set_error (bfd_error_invalid_operation
);
340 /* For the time being, a BFD may not seek to it's end. The problem
341 is that we don't easily have a way to recognize the end of an
342 element in an archive. */
343 BFD_ASSERT (direction
== SEEK_SET
|| direction
== SEEK_CUR
);
345 if (direction
!= SEEK_CUR
)
348 if ((direction
== SEEK_CUR
&& position
== 0)
349 || (direction
== SEEK_SET
&& (ufile_ptr
) position
== abfd
->where
))
352 result
= abfd
->iovec
->bseek (abfd
, position
, direction
);
355 /* An EINVAL error probably means that the file offset was
358 bfd_set_error (bfd_error_file_truncated
);
360 bfd_set_error (bfd_error_system_call
);
364 /* Adjust `where' field. */
365 if (direction
== SEEK_CUR
)
366 abfd
->where
+= position
;
368 abfd
->where
= position
;
379 long bfd_get_mtime (bfd *abfd);
382 Return the file modification time (as read from the file system, or
383 from the archive header for archive members).
388 bfd_get_mtime (bfd
*abfd
)
395 if (bfd_stat (abfd
, &buf
) != 0)
398 abfd
->mtime
= buf
.st_mtime
; /* Save value in case anyone wants it */
407 ufile_ptr bfd_get_size (bfd *abfd);
410 Return the file size (as read from file system) for the file
411 associated with BFD @var{abfd}.
413 The initial motivation for, and use of, this routine is not
414 so we can get the exact size of the object the BFD applies to, since
415 that might not be generally possible (archive members for example).
416 It would be ideal if someone could eventually modify
417 it so that such results were guaranteed.
419 Instead, we want to ask questions like "is this NNN byte sized
420 object I'm about to try read from file offset YYY reasonable?"
421 As as example of where we might do this, some object formats
422 use string tables for which the first <<sizeof (long)>> bytes of the
423 table contain the size of the table itself, including the size bytes.
424 If an application tries to read what it thinks is one of these
425 string tables, without some way to validate the size, and for
426 some reason the size is wrong (byte swapping error, wrong location
427 for the string table, etc.), the only clue is likely to be a read
428 error when it tries to read the table, or a "virtual memory
429 exhausted" error when it tries to allocate 15 bazillon bytes
430 of space for the 15 bazillon byte table it is about to read.
431 This function at least allows us to answer the question, "is the
434 A return value of zero indicates the file size is unknown.
438 bfd_get_size (bfd
*abfd
)
440 /* A size of 0 means we haven't yet called bfd_stat. A size of 1
441 means we have a cached value of 0, ie. unknown. */
442 if (abfd
->size
<= 1 || bfd_write_p (abfd
))
446 if (abfd
->size
== 1 && !bfd_write_p (abfd
))
449 if (bfd_stat (abfd
, &buf
) != 0
451 || buf
.st_size
- (ufile_ptr
) buf
.st_size
!= 0)
456 abfd
->size
= buf
.st_size
;
466 ufile_ptr bfd_get_file_size (bfd *abfd);
469 Return the file size (as read from file system) for the file
470 associated with BFD @var{abfd}. It supports both normal files
471 and archive elements.
476 bfd_get_file_size (bfd
*abfd
)
478 ufile_ptr file_size
, archive_size
= (ufile_ptr
) -1;
480 if (abfd
->my_archive
!= NULL
481 && !bfd_is_thin_archive (abfd
->my_archive
))
483 struct areltdata
*adata
= (struct areltdata
*) abfd
->arelt_data
;
484 archive_size
= adata
->parsed_size
;
485 /* If the archive is compressed we can't compare against file size. */
486 if (memcmp (((struct ar_hdr
*) adata
->arch_header
)->ar_fmag
,
489 abfd
= abfd
->my_archive
;
492 file_size
= bfd_get_size (abfd
);
493 if (archive_size
< file_size
)
503 void *bfd_mmap (bfd *abfd, void *addr, bfd_size_type len,
504 int prot, int flags, file_ptr offset,
505 void **map_addr, bfd_size_type *map_len);
508 Return mmap()ed region of the file, if possible and implemented.
509 LEN and OFFSET do not need to be page aligned. The page aligned
510 address and length are written to MAP_ADDR and MAP_LEN.
515 bfd_mmap (bfd
*abfd
, void *addr
, bfd_size_type len
,
516 int prot
, int flags
, file_ptr offset
,
517 void **map_addr
, bfd_size_type
*map_len
)
519 while (abfd
->my_archive
!= NULL
520 && !bfd_is_thin_archive (abfd
->my_archive
))
522 offset
+= abfd
->origin
;
523 abfd
= abfd
->my_archive
;
526 if (abfd
->iovec
== NULL
)
528 bfd_set_error (bfd_error_invalid_operation
);
532 return abfd
->iovec
->bmmap (abfd
, addr
, len
, prot
, flags
, offset
,
536 /* Memory file I/O operations. */
539 memory_bread (bfd
*abfd
, void *ptr
, file_ptr size
)
541 struct bfd_in_memory
*bim
;
544 bim
= (struct bfd_in_memory
*) abfd
->iostream
;
546 if (abfd
->where
+ get
> bim
->size
)
548 if (bim
->size
< (bfd_size_type
) abfd
->where
)
551 get
= bim
->size
- abfd
->where
;
552 bfd_set_error (bfd_error_file_truncated
);
554 memcpy (ptr
, bim
->buffer
+ abfd
->where
, (size_t) get
);
559 memory_bwrite (bfd
*abfd
, const void *ptr
, file_ptr size
)
561 struct bfd_in_memory
*bim
= (struct bfd_in_memory
*) abfd
->iostream
;
563 if (abfd
->where
+ size
> bim
->size
)
565 bfd_size_type newsize
, oldsize
;
567 oldsize
= (bim
->size
+ 127) & ~(bfd_size_type
) 127;
568 bim
->size
= abfd
->where
+ size
;
569 /* Round up to cut down on memory fragmentation */
570 newsize
= (bim
->size
+ 127) & ~(bfd_size_type
) 127;
571 if (newsize
> oldsize
)
573 bim
->buffer
= (bfd_byte
*) bfd_realloc_or_free (bim
->buffer
, newsize
);
574 if (bim
->buffer
== NULL
)
579 if (newsize
> bim
->size
)
580 memset (bim
->buffer
+ bim
->size
, 0, newsize
- bim
->size
);
583 memcpy (bim
->buffer
+ abfd
->where
, ptr
, (size_t) size
);
588 memory_btell (bfd
*abfd
)
594 memory_bseek (bfd
*abfd
, file_ptr position
, int direction
)
597 struct bfd_in_memory
*bim
;
599 bim
= (struct bfd_in_memory
*) abfd
->iostream
;
601 if (direction
== SEEK_SET
)
604 nwhere
= abfd
->where
+ position
;
613 if ((bfd_size_type
)nwhere
> bim
->size
)
615 if (abfd
->direction
== write_direction
616 || abfd
->direction
== both_direction
)
618 bfd_size_type newsize
, oldsize
;
620 oldsize
= (bim
->size
+ 127) & ~(bfd_size_type
) 127;
622 /* Round up to cut down on memory fragmentation */
623 newsize
= (bim
->size
+ 127) & ~(bfd_size_type
) 127;
624 if (newsize
> oldsize
)
626 bim
->buffer
= (bfd_byte
*) bfd_realloc_or_free (bim
->buffer
, newsize
);
627 if (bim
->buffer
== NULL
)
633 memset (bim
->buffer
+ oldsize
, 0, newsize
- oldsize
);
638 abfd
->where
= bim
->size
;
640 bfd_set_error (bfd_error_file_truncated
);
648 memory_bclose (struct bfd
*abfd
)
650 struct bfd_in_memory
*bim
= (struct bfd_in_memory
*) abfd
->iostream
;
652 if (bim
->buffer
!= NULL
)
655 abfd
->iostream
= NULL
;
661 memory_bflush (bfd
*abfd ATTRIBUTE_UNUSED
)
667 memory_bstat (bfd
*abfd
, struct stat
*statbuf
)
669 struct bfd_in_memory
*bim
= (struct bfd_in_memory
*) abfd
->iostream
;
671 memset (statbuf
, 0, sizeof (*statbuf
));
672 statbuf
->st_size
= bim
->size
;
678 memory_bmmap (bfd
*abfd ATTRIBUTE_UNUSED
, void *addr ATTRIBUTE_UNUSED
,
679 bfd_size_type len ATTRIBUTE_UNUSED
, int prot ATTRIBUTE_UNUSED
,
680 int flags ATTRIBUTE_UNUSED
, file_ptr offset ATTRIBUTE_UNUSED
,
681 void **map_addr ATTRIBUTE_UNUSED
,
682 bfd_size_type
*map_len ATTRIBUTE_UNUSED
)
687 const struct bfd_iovec _bfd_memory_iovec
=
689 &memory_bread
, &memory_bwrite
, &memory_btell
, &memory_bseek
,
690 &memory_bclose
, &memory_bflush
, &memory_bstat
, &memory_bmmap