1 /* Compressed section support (intended for debug sections).
2 Copyright (C) 2008-2014 Free Software Foundation, Inc.
4 This file is part of BFD, the Binary File Descriptor library.
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 3 of the License, or
9 (at your option) any later version.
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with this program; if not, write to the Free Software
18 Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
19 MA 02110-1301, USA. */
27 #include "safe-ctype.h"
31 decompress_contents (bfd_byte
*compressed_buffer
,
32 bfd_size_type compressed_size
,
33 bfd_byte
*uncompressed_buffer
,
34 bfd_size_type uncompressed_size
)
39 /* It is possible the section consists of several compressed
40 buffers concatenated together, so we uncompress in a loop. */
44 strm
.avail_in
= compressed_size
- 12;
45 strm
.next_in
= (Bytef
*) compressed_buffer
+ 12;
46 strm
.avail_out
= uncompressed_size
;
48 BFD_ASSERT (Z_OK
== 0);
49 rc
= inflateInit (&strm
);
50 while (strm
.avail_in
> 0 && strm
.avail_out
> 0)
54 strm
.next_out
= ((Bytef
*) uncompressed_buffer
55 + (uncompressed_size
- strm
.avail_out
));
56 rc
= inflate (&strm
, Z_FINISH
);
57 if (rc
!= Z_STREAM_END
)
59 rc
= inflateReset (&strm
);
61 rc
|= inflateEnd (&strm
);
62 return rc
== Z_OK
&& strm
.avail_out
== 0;
68 bfd_compress_section_contents
71 bfd_boolean bfd_compress_section_contents
72 (bfd *abfd, asection *section, bfd_byte *uncompressed_buffer,
73 bfd_size_type uncompressed_size);
77 Compress data of the size specified in @var{uncompressed_size}
78 and pointed to by @var{uncompressed_buffer} using zlib and store
79 as the contents field. This function assumes the contents
80 field was allocated using bfd_malloc() or equivalent. If zlib
81 is not installed on this machine, the input is unmodified.
83 Return @code{TRUE} if the full section contents is compressed
88 bfd_compress_section_contents (bfd
*abfd ATTRIBUTE_UNUSED
,
89 sec_ptr sec ATTRIBUTE_UNUSED
,
90 bfd_byte
*uncompressed_buffer ATTRIBUTE_UNUSED
,
91 bfd_size_type uncompressed_size ATTRIBUTE_UNUSED
)
94 bfd_set_error (bfd_error_invalid_operation
);
97 uLong compressed_size
;
98 bfd_byte
*compressed_buffer
;
100 compressed_size
= compressBound (uncompressed_size
) + 12;
101 compressed_buffer
= (bfd_byte
*) bfd_malloc (compressed_size
);
103 if (compressed_buffer
== NULL
)
106 if (compress ((Bytef
*) compressed_buffer
+ 12,
108 (const Bytef
*) uncompressed_buffer
,
109 uncompressed_size
) != Z_OK
)
111 free (compressed_buffer
);
112 bfd_set_error (bfd_error_bad_value
);
116 /* Write the zlib header. In this case, it should be "ZLIB" followed
117 by the uncompressed section size, 8 bytes in big-endian order. */
118 memcpy (compressed_buffer
, "ZLIB", 4);
119 compressed_buffer
[11] = uncompressed_size
; uncompressed_size
>>= 8;
120 compressed_buffer
[10] = uncompressed_size
; uncompressed_size
>>= 8;
121 compressed_buffer
[9] = uncompressed_size
; uncompressed_size
>>= 8;
122 compressed_buffer
[8] = uncompressed_size
; uncompressed_size
>>= 8;
123 compressed_buffer
[7] = uncompressed_size
; uncompressed_size
>>= 8;
124 compressed_buffer
[6] = uncompressed_size
; uncompressed_size
>>= 8;
125 compressed_buffer
[5] = uncompressed_size
; uncompressed_size
>>= 8;
126 compressed_buffer
[4] = uncompressed_size
;
127 compressed_size
+= 12;
129 /* Free the uncompressed contents if we compress in place. */
130 if (uncompressed_buffer
== sec
->contents
)
131 free (uncompressed_buffer
);
133 sec
->contents
= compressed_buffer
;
134 sec
->size
= compressed_size
;
135 sec
->compress_status
= COMPRESS_SECTION_DONE
;
138 #endif /* HAVE_ZLIB_H */
143 bfd_get_full_section_contents
146 bfd_boolean bfd_get_full_section_contents
147 (bfd *abfd, asection *section, bfd_byte **ptr);
150 Read all data from @var{section} in BFD @var{abfd}, decompress
151 if needed, and store in @var{*ptr}. If @var{*ptr} is NULL,
152 return @var{*ptr} with memory malloc'd by this function.
154 Return @code{TRUE} if the full section contents is retrieved
159 bfd_get_full_section_contents (bfd
*abfd
, sec_ptr sec
, bfd_byte
**ptr
)
165 bfd_size_type save_size
;
166 bfd_size_type save_rawsize
;
167 bfd_byte
*compressed_buffer
;
170 if (abfd
->direction
!= write_direction
&& sec
->rawsize
!= 0)
177 switch (sec
->compress_status
)
179 case COMPRESS_SECTION_NONE
:
182 p
= (bfd_byte
*) bfd_malloc (sz
);
186 if (!bfd_get_section_contents (abfd
, sec
, p
, 0, sz
))
195 case DECOMPRESS_SECTION_SIZED
:
197 bfd_set_error (bfd_error_invalid_operation
);
200 /* Read in the full compressed section contents. */
201 compressed_buffer
= (bfd_byte
*) bfd_malloc (sec
->compressed_size
);
202 if (compressed_buffer
== NULL
)
204 save_rawsize
= sec
->rawsize
;
205 save_size
= sec
->size
;
206 /* Clear rawsize, set size to compressed size and set compress_status
207 to COMPRESS_SECTION_NONE. If the compressed size is bigger than
208 the uncompressed size, bfd_get_section_contents will fail. */
210 sec
->size
= sec
->compressed_size
;
211 sec
->compress_status
= COMPRESS_SECTION_NONE
;
212 ret
= bfd_get_section_contents (abfd
, sec
, compressed_buffer
,
213 0, sec
->compressed_size
);
214 /* Restore rawsize and size. */
215 sec
->rawsize
= save_rawsize
;
216 sec
->size
= save_size
;
217 sec
->compress_status
= DECOMPRESS_SECTION_SIZED
;
219 goto fail_compressed
;
222 p
= (bfd_byte
*) bfd_malloc (sz
);
224 goto fail_compressed
;
226 if (!decompress_contents (compressed_buffer
, sec
->compressed_size
, p
, sz
))
228 bfd_set_error (bfd_error_bad_value
);
232 free (compressed_buffer
);
236 free (compressed_buffer
);
241 case COMPRESS_SECTION_DONE
:
244 p
= (bfd_byte
*) bfd_malloc (sz
);
249 memcpy (p
, sec
->contents
, sz
);
259 bfd_cache_section_contents
262 void bfd_cache_section_contents
263 (asection *sec, void *contents);
266 Stash @var(contents) so any following reads of @var(sec) do
267 not need to decompress again.
271 bfd_cache_section_contents (asection
*sec
, void *contents
)
273 if (sec
->compress_status
== DECOMPRESS_SECTION_SIZED
)
274 sec
->compress_status
= COMPRESS_SECTION_DONE
;
275 sec
->contents
= contents
;
276 sec
->flags
|= SEC_IN_MEMORY
;
282 bfd_is_section_compressed
285 bfd_boolean bfd_is_section_compressed
286 (bfd *abfd, asection *section);
289 Return @code{TRUE} if @var{section} is compressed.
293 bfd_is_section_compressed (bfd
*abfd
, sec_ptr sec
)
295 bfd_byte compressed_buffer
[12];
296 unsigned int saved
= sec
->compress_status
;
297 bfd_boolean compressed
;
299 /* Don't decompress the section. */
300 sec
->compress_status
= COMPRESS_SECTION_NONE
;
302 /* Read the zlib header. In this case, it should be "ZLIB" followed
303 by the uncompressed section size, 8 bytes in big-endian order. */
304 compressed
= (bfd_get_section_contents (abfd
, sec
, compressed_buffer
, 0, 12)
305 && CONST_STRNEQ ((char*) compressed_buffer
, "ZLIB"));
307 /* Check for the pathalogical case of a debug string section that
308 contains the string ZLIB.... as the first entry. We assume that
309 no uncompressed .debug_str section would ever be big enough to
310 have the first byte of its (big-endian) size be non-zero. */
312 && strcmp (sec
->name
, ".debug_str") == 0
313 && ISPRINT (compressed_buffer
[4]))
316 /* Restore compress_status. */
317 sec
->compress_status
= saved
;
323 bfd_init_section_decompress_status
326 bfd_boolean bfd_init_section_decompress_status
327 (bfd *abfd, asection *section);
330 Record compressed section size, update section size with
331 decompressed size and set compress_status to
332 DECOMPRESS_SECTION_SIZED.
334 Return @code{FALSE} if the section is not a valid compressed
335 section or zlib is not installed on this machine. Otherwise,
340 bfd_init_section_decompress_status (bfd
*abfd ATTRIBUTE_UNUSED
,
341 sec_ptr sec ATTRIBUTE_UNUSED
)
344 bfd_set_error (bfd_error_invalid_operation
);
347 bfd_byte compressed_buffer
[12];
348 bfd_size_type uncompressed_size
;
350 if (sec
->rawsize
!= 0
351 || sec
->contents
!= NULL
352 || sec
->compress_status
!= COMPRESS_SECTION_NONE
353 || !bfd_get_section_contents (abfd
, sec
, compressed_buffer
, 0, 12))
355 bfd_set_error (bfd_error_invalid_operation
);
359 /* Read the zlib header. In this case, it should be "ZLIB" followed
360 by the uncompressed section size, 8 bytes in big-endian order. */
361 if (! CONST_STRNEQ ((char*) compressed_buffer
, "ZLIB"))
363 bfd_set_error (bfd_error_wrong_format
);
367 uncompressed_size
= compressed_buffer
[4]; uncompressed_size
<<= 8;
368 uncompressed_size
+= compressed_buffer
[5]; uncompressed_size
<<= 8;
369 uncompressed_size
+= compressed_buffer
[6]; uncompressed_size
<<= 8;
370 uncompressed_size
+= compressed_buffer
[7]; uncompressed_size
<<= 8;
371 uncompressed_size
+= compressed_buffer
[8]; uncompressed_size
<<= 8;
372 uncompressed_size
+= compressed_buffer
[9]; uncompressed_size
<<= 8;
373 uncompressed_size
+= compressed_buffer
[10]; uncompressed_size
<<= 8;
374 uncompressed_size
+= compressed_buffer
[11];
376 sec
->compressed_size
= sec
->size
;
377 sec
->size
= uncompressed_size
;
378 sec
->compress_status
= DECOMPRESS_SECTION_SIZED
;
386 bfd_init_section_compress_status
389 bfd_boolean bfd_init_section_compress_status
390 (bfd *abfd, asection *section);
393 If open for read, compress section, update section size with
394 compressed size and set compress_status to COMPRESS_SECTION_DONE.
396 Return @code{FALSE} if the section is not a valid compressed
397 section or zlib is not installed on this machine. Otherwise,
402 bfd_init_section_compress_status (bfd
*abfd ATTRIBUTE_UNUSED
,
403 sec_ptr sec ATTRIBUTE_UNUSED
)
406 bfd_set_error (bfd_error_invalid_operation
);
409 bfd_size_type uncompressed_size
;
410 bfd_byte
*uncompressed_buffer
;
413 /* Error if not opened for read. */
414 if (abfd
->direction
!= read_direction
417 || sec
->contents
!= NULL
418 || sec
->compress_status
!= COMPRESS_SECTION_NONE
)
420 bfd_set_error (bfd_error_invalid_operation
);
424 /* Read in the full section contents and compress it. */
425 uncompressed_size
= sec
->size
;
426 uncompressed_buffer
= (bfd_byte
*) bfd_malloc (uncompressed_size
);
427 if (!bfd_get_section_contents (abfd
, sec
, uncompressed_buffer
,
428 0, uncompressed_size
))
431 ret
= bfd_compress_section_contents (abfd
, sec
,
435 free (uncompressed_buffer
);