diff options
Diffstat (limited to 'bfd/compress.c')
| -rw-r--r-- | bfd/compress.c | 122 |
1 files changed, 122 insertions, 0 deletions
diff --git a/bfd/compress.c b/bfd/compress.c new file mode 100644 index 0000000..a2fcff7 --- /dev/null +++ b/bfd/compress.c @@ -0,0 +1,122 @@ +/* ELF attributes support (based on ARM EABI attributes). + Copyright 2008 + Free Software Foundation, Inc. + + This file is part of BFD, the Binary File Descriptor library. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software + Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, + MA 02110-1301, USA. */ + +#include "config.h" +#include "sysdep.h" +#include "bfd.h" +#include "libbfd.h" +#ifdef HAVE_ZLIB_H +#include <zlib.h> +#endif + +/* +FUNCTION + bfd_uncompress_section_contents + +SYNOPSIS + bfd_boolean bfd_uncompress_section_contents + (bfd_byte **buffer, bfd_size_type *size); + +DESCRIPTION + + Uncompresses a section that was compressed using zlib, in place. At + the call to this function, *@var{buffer} and *@var{size} should point + to the section contents to be uncompressed. At the end of the + function, *@var{buffer} and *@var{size} will point to the uncompressed + contents. This function assumes *BUFFER was allocated using + bfd_malloc() or equivalent. If the section is not a valid compressed + section, or zlib is not installed on this machine, the input is + unmodified. + + Returns @code{FALSE} if unable to uncompress successfully; in that case + the input is unmodified. Otherwise, returns @code{TRUE}. +*/ + +bfd_boolean +bfd_uncompress_section_contents (bfd_byte **buffer, bfd_size_type *size) +{ +#ifndef HAVE_ZLIB_H + /* These are just to quiet gcc. */ + buffer = 0; + size = 0; + return FALSE; +#else + bfd_size_type compressed_size = *size; + bfd_byte *compressed_buffer = *buffer; + bfd_size_type uncompressed_size; + bfd_byte *uncompressed_buffer; + z_stream strm; + int rc; + bfd_size_type header_size = 12; + + /* Read the zlib header. In this case, it should be "ZLIB" followed + by the uncompressed section size, 8 bytes in big-endian order. */ + if (compressed_size < header_size + || ! CONST_STRNEQ ((char*) compressed_buffer, "ZLIB")) + return FALSE; + uncompressed_size = compressed_buffer[4]; uncompressed_size <<= 8; + uncompressed_size += compressed_buffer[5]; uncompressed_size <<= 8; + uncompressed_size += compressed_buffer[6]; uncompressed_size <<= 8; + uncompressed_size += compressed_buffer[7]; uncompressed_size <<= 8; + uncompressed_size += compressed_buffer[8]; uncompressed_size <<= 8; + uncompressed_size += compressed_buffer[9]; uncompressed_size <<= 8; + uncompressed_size += compressed_buffer[10]; uncompressed_size <<= 8; + uncompressed_size += compressed_buffer[11]; + + /* It is possible the section consists of several compressed + buffers concatenated together, so we uncompress in a loop. */ + strm.zalloc = NULL; + strm.zfree = NULL; + strm.opaque = NULL; + strm.avail_in = compressed_size - header_size; + strm.next_in = (Bytef*) compressed_buffer + header_size; + strm.avail_out = uncompressed_size; + uncompressed_buffer = bfd_malloc (uncompressed_size); + if (! uncompressed_buffer) + return FALSE; + + rc = inflateInit (&strm); + while (strm.avail_in > 0) + { + if (rc != Z_OK) + goto fail; + strm.next_out = ((Bytef*) uncompressed_buffer + + (uncompressed_size - strm.avail_out)); + rc = inflate (&strm, Z_FINISH); + if (rc != Z_STREAM_END) + goto fail; + rc = inflateReset (&strm); + } + rc = inflateEnd (&strm); + if (rc != Z_OK + || strm.avail_out != 0) + goto fail; + + free (compressed_buffer); + *buffer = uncompressed_buffer; + *size = uncompressed_size; + return TRUE; + + fail: + free (uncompressed_buffer); + return FALSE; +#endif /* HAVE_ZLIB_H */ +} |