1 /* Compressed section support (intended for debug sections).
2 Copyright 2008, 2010, 2011, 2012
3 Free Software Foundation, Inc.
5 This file is part of BFD, the Binary File Descriptor library.
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 3 of the License, or
10 (at your option) any later version.
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with this program; if not, write to the Free Software
19 Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
20 MA 02110-1301, USA. */
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 rc = inflateInit (&strm);
49 while (strm.avail_in > 0 && strm.avail_out > 0)
53 strm.next_out = ((Bytef*) uncompressed_buffer
54 + (uncompressed_size - strm.avail_out));
55 rc = inflate (&strm, Z_FINISH);
56 if (rc != Z_STREAM_END)
58 rc = inflateReset (&strm);
60 rc = inflateEnd (&strm);
61 return rc == Z_OK && strm.avail_out == 0;
67 bfd_compress_section_contents
70 bfd_boolean bfd_compress_section_contents
71 (bfd *abfd, asection *section, bfd_byte *uncompressed_buffer,
72 bfd_size_type uncompressed_size);
76 Compress data of the size specified in @var{uncompressed_size}
77 and pointed to by @var{uncompressed_buffer} using zlib and store
78 as the contents field. This function assumes the contents
79 field was allocated using bfd_malloc() or equivalent. If zlib
80 is not installed on this machine, the input is unmodified.
82 Return @code{TRUE} if the full section contents is compressed
87 bfd_compress_section_contents (bfd *abfd ATTRIBUTE_UNUSED,
88 sec_ptr sec ATTRIBUTE_UNUSED,
89 bfd_byte *uncompressed_buffer ATTRIBUTE_UNUSED,
90 bfd_size_type uncompressed_size ATTRIBUTE_UNUSED)
93 bfd_set_error (bfd_error_invalid_operation);
96 uLong compressed_size;
97 bfd_byte *compressed_buffer;
99 compressed_size = compressBound (uncompressed_size) + 12;
100 compressed_buffer = (bfd_byte *) bfd_malloc (compressed_size);
102 if (compressed_buffer == NULL)
105 if (compress ((Bytef*) compressed_buffer + 12,
107 (const Bytef*) uncompressed_buffer,
108 uncompressed_size) != Z_OK)
110 free (compressed_buffer);
111 bfd_set_error (bfd_error_bad_value);
115 /* Write the zlib header. In this case, it should be "ZLIB" followed
116 by the uncompressed section size, 8 bytes in big-endian order. */
117 memcpy (compressed_buffer, "ZLIB", 4);
118 compressed_buffer[11] = uncompressed_size; uncompressed_size >>= 8;
119 compressed_buffer[10] = uncompressed_size; uncompressed_size >>= 8;
120 compressed_buffer[9] = uncompressed_size; uncompressed_size >>= 8;
121 compressed_buffer[8] = uncompressed_size; uncompressed_size >>= 8;
122 compressed_buffer[7] = uncompressed_size; uncompressed_size >>= 8;
123 compressed_buffer[6] = uncompressed_size; uncompressed_size >>= 8;
124 compressed_buffer[5] = uncompressed_size; uncompressed_size >>= 8;
125 compressed_buffer[4] = uncompressed_size;
126 compressed_size += 12;
128 /* Free the uncompressed contents if we compress in place. */
129 if (uncompressed_buffer == sec->contents)
130 free (uncompressed_buffer);
132 sec->contents = compressed_buffer;
133 sec->size = compressed_size;
134 sec->compress_status = COMPRESS_SECTION_DONE;
137 #endif /* HAVE_ZLIB_H */
142 bfd_get_full_section_contents
145 bfd_boolean bfd_get_full_section_contents
146 (bfd *abfd, asection *section, bfd_byte **ptr);
149 Read all data from @var{section} in BFD @var{abfd}, decompress
150 if needed, and store in @var{*ptr}. If @var{*ptr} is NULL,
151 return @var{*ptr} with memory malloc'd by this function.
153 Return @code{TRUE} if the full section contents is retrieved
158 bfd_get_full_section_contents (bfd *abfd, sec_ptr sec, bfd_byte **ptr)
164 bfd_size_type save_size;
165 bfd_size_type save_rawsize;
166 bfd_byte *compressed_buffer;
169 if (abfd->direction != write_direction && sec->rawsize != 0)
176 switch (sec->compress_status)
178 case COMPRESS_SECTION_NONE:
181 p = (bfd_byte *) bfd_malloc (sz);
185 if (!bfd_get_section_contents (abfd, sec, p, 0, sz))
194 case DECOMPRESS_SECTION_SIZED:
196 bfd_set_error (bfd_error_invalid_operation);
199 /* Read in the full compressed section contents. */
200 compressed_buffer = (bfd_byte *) bfd_malloc (sec->compressed_size);
201 if (compressed_buffer == NULL)
203 save_rawsize = sec->rawsize;
204 save_size = sec->size;
205 /* Clear rawsize, set size to compressed size and set compress_status
206 to COMPRESS_SECTION_NONE. If the compressed size is bigger than
207 the uncompressed size, bfd_get_section_contents will fail. */
209 sec->size = sec->compressed_size;
210 sec->compress_status = COMPRESS_SECTION_NONE;
211 ret = bfd_get_section_contents (abfd, sec, compressed_buffer,
212 0, sec->compressed_size);
213 /* Restore rawsize and size. */
214 sec->rawsize = save_rawsize;
215 sec->size = save_size;
216 sec->compress_status = DECOMPRESS_SECTION_SIZED;
218 goto fail_compressed;
221 p = (bfd_byte *) bfd_malloc (sz);
223 goto fail_compressed;
225 if (!decompress_contents (compressed_buffer, sec->compressed_size, p, sz))
227 bfd_set_error (bfd_error_bad_value);
231 free (compressed_buffer);
235 free (compressed_buffer);
240 case COMPRESS_SECTION_DONE:
243 p = (bfd_byte *) bfd_malloc (sz);
248 memcpy (p, sec->contents, sz);
258 bfd_cache_section_contents
261 void bfd_cache_section_contents
262 (asection *sec, void *contents);
265 Stash @var(contents) so any following reads of @var(sec) do
266 not need to decompress again.
270 bfd_cache_section_contents (asection *sec, void *contents)
272 if (sec->compress_status == DECOMPRESS_SECTION_SIZED)
273 sec->compress_status = COMPRESS_SECTION_DONE;
274 sec->contents = contents;
275 sec->flags |= SEC_IN_MEMORY;
281 bfd_is_section_compressed
284 bfd_boolean bfd_is_section_compressed
285 (bfd *abfd, asection *section);
288 Return @code{TRUE} if @var{section} is compressed.
292 bfd_is_section_compressed (bfd *abfd, sec_ptr sec)
294 bfd_byte compressed_buffer [12];
295 unsigned int saved = sec->compress_status;
296 bfd_boolean compressed;
298 /* Don't decompress the section. */
299 sec->compress_status = COMPRESS_SECTION_NONE;
301 /* Read the zlib header. In this case, it should be "ZLIB" followed
302 by the uncompressed section size, 8 bytes in big-endian order. */
303 compressed = (bfd_get_section_contents (abfd, sec, compressed_buffer, 0, 12)
304 && CONST_STRNEQ ((char*) compressed_buffer, "ZLIB"));
306 /* Restore compress_status. */
307 sec->compress_status = saved;
313 bfd_init_section_decompress_status
316 bfd_boolean bfd_init_section_decompress_status
317 (bfd *abfd, asection *section);
320 Record compressed section size, update section size with
321 decompressed size and set compress_status to
322 DECOMPRESS_SECTION_SIZED.
324 Return @code{FALSE} if the section is not a valid compressed
325 section or zlib is not installed on this machine. Otherwise,
330 bfd_init_section_decompress_status (bfd *abfd ATTRIBUTE_UNUSED,
331 sec_ptr sec ATTRIBUTE_UNUSED)
334 bfd_set_error (bfd_error_invalid_operation);
337 bfd_byte compressed_buffer [12];
338 bfd_size_type uncompressed_size;
340 if (sec->rawsize != 0
341 || sec->contents != NULL
342 || sec->compress_status != COMPRESS_SECTION_NONE
343 || !bfd_get_section_contents (abfd, sec, compressed_buffer, 0, 12))
345 bfd_set_error (bfd_error_invalid_operation);
349 /* Read the zlib header. In this case, it should be "ZLIB" followed
350 by the uncompressed section size, 8 bytes in big-endian order. */
351 if (! CONST_STRNEQ ((char*) compressed_buffer, "ZLIB"))
353 bfd_set_error (bfd_error_wrong_format);
357 uncompressed_size = compressed_buffer[4]; uncompressed_size <<= 8;
358 uncompressed_size += compressed_buffer[5]; uncompressed_size <<= 8;
359 uncompressed_size += compressed_buffer[6]; uncompressed_size <<= 8;
360 uncompressed_size += compressed_buffer[7]; uncompressed_size <<= 8;
361 uncompressed_size += compressed_buffer[8]; uncompressed_size <<= 8;
362 uncompressed_size += compressed_buffer[9]; uncompressed_size <<= 8;
363 uncompressed_size += compressed_buffer[10]; uncompressed_size <<= 8;
364 uncompressed_size += compressed_buffer[11];
366 sec->compressed_size = sec->size;
367 sec->size = uncompressed_size;
368 sec->compress_status = DECOMPRESS_SECTION_SIZED;
376 bfd_init_section_compress_status
379 bfd_boolean bfd_init_section_compress_status
380 (bfd *abfd, asection *section);
383 If open for read, compress section, update section size with
384 compressed size and set compress_status to COMPRESS_SECTION_DONE.
386 Return @code{FALSE} if the section is not a valid compressed
387 section or zlib is not installed on this machine. Otherwise,
392 bfd_init_section_compress_status (bfd *abfd ATTRIBUTE_UNUSED,
393 sec_ptr sec ATTRIBUTE_UNUSED)
396 bfd_set_error (bfd_error_invalid_operation);
399 bfd_size_type uncompressed_size;
400 bfd_byte *uncompressed_buffer;
403 /* Error if not opened for read. */
404 if (abfd->direction != read_direction
407 || sec->contents != NULL
408 || sec->compress_status != COMPRESS_SECTION_NONE)
410 bfd_set_error (bfd_error_invalid_operation);
414 /* Read in the full section contents and compress it. */
415 uncompressed_size = sec->size;
416 uncompressed_buffer = (bfd_byte *) bfd_malloc (uncompressed_size);
417 if (!bfd_get_section_contents (abfd, sec, uncompressed_buffer,
418 0, uncompressed_size))
421 ret = bfd_compress_section_contents (abfd, sec,
425 free (uncompressed_buffer);