[binutils.git] / bfd / compress.c

/* Compressed section support (intended for debug sections).
   Copyright (C) 2008-2015 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 "sysdep.h"
#include <zlib.h>
#include "bfd.h"
#include "libbfd.h"
#include "safe-ctype.h"

static bfd_boolean
decompress_contents (bfd_byte *compressed_buffer,
		     bfd_size_type compressed_size,
		     bfd_byte *uncompressed_buffer,
		     bfd_size_type uncompressed_size)
{
  z_stream strm;
  int rc;

  /* 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 - 12;
  strm.next_in = (Bytef*) compressed_buffer + 12;
  strm.avail_out = uncompressed_size;

  BFD_ASSERT (Z_OK == 0);
  rc = inflateInit (&strm);
  while (strm.avail_in > 0 && strm.avail_out > 0)
    {
      if (rc != Z_OK)
	break;
      strm.next_out = ((Bytef*) uncompressed_buffer
                       + (uncompressed_size - strm.avail_out));
      rc = inflate (&strm, Z_FINISH);
      if (rc != Z_STREAM_END)
	break;
      rc = inflateReset (&strm);
    }
  rc |= inflateEnd (&strm);
  return rc == Z_OK && strm.avail_out == 0;
}

/* Compress data of the size specified in @var{uncompressed_size}
   and pointed to by @var{uncompressed_buffer} using zlib and store
   as the contents field.  This function assumes the contents
   field was allocated using bfd_malloc() or equivalent.  If zlib
   is not installed on this machine, the input is unmodified.

   Return @code{TRUE} if the full section contents is compressed
   successfully.  */

static bfd_boolean
bfd_compress_section_contents (bfd *abfd ATTRIBUTE_UNUSED, sec_ptr sec,
			       bfd_byte *uncompressed_buffer,
			       bfd_size_type uncompressed_size)
{
  uLong compressed_size;
  bfd_byte *compressed_buffer;

  compressed_size = compressBound (uncompressed_size) + 12;
  compressed_buffer = (bfd_byte *) bfd_malloc (compressed_size);

  if (compressed_buffer == NULL)
    return FALSE;

  if (compress ((Bytef*) compressed_buffer + 12,
		&compressed_size,
		(const Bytef*) uncompressed_buffer,
		uncompressed_size) != Z_OK)
    {
      free (compressed_buffer);
      bfd_set_error (bfd_error_bad_value);
      return FALSE;
    }

  compressed_size += 12;

  /* PR binutils/18087: If compression didn't make the section smaller,
     just keep it uncompressed.  */
  if (compressed_size < uncompressed_size)
    {
      /* Write the zlib header.  In this case, it should be "ZLIB" followed
	 by the uncompressed section size, 8 bytes in big-endian order.  */
      memcpy (compressed_buffer, "ZLIB", 4);
      compressed_buffer[11] = uncompressed_size; uncompressed_size >>= 8;
      compressed_buffer[10] = uncompressed_size; uncompressed_size >>= 8;
      compressed_buffer[9] = uncompressed_size; uncompressed_size >>= 8;
      compressed_buffer[8] = uncompressed_size; uncompressed_size >>= 8;
      compressed_buffer[7] = uncompressed_size; uncompressed_size >>= 8;
      compressed_buffer[6] = uncompressed_size; uncompressed_size >>= 8;
      compressed_buffer[5] = uncompressed_size; uncompressed_size >>= 8;
      compressed_buffer[4] = uncompressed_size;

      free (uncompressed_buffer);
      sec->contents = compressed_buffer;
      sec->size = compressed_size;
      sec->compress_status = COMPRESS_SECTION_DONE;
    }
  else
    {
      sec->contents = uncompressed_buffer;
      sec->compress_status = COMPRESS_SECTION_NONE;
    }

  return TRUE;
}

/*
FUNCTION
	bfd_get_full_section_contents

SYNOPSIS
	bfd_boolean bfd_get_full_section_contents
	  (bfd *abfd, asection *section, bfd_byte **ptr);

DESCRIPTION
	Read all data from @var{section} in BFD @var{abfd}, decompress
	if needed, and store in @var{*ptr}.  If @var{*ptr} is NULL,
	return @var{*ptr} with memory malloc'd by this function.

	Return @code{TRUE} if the full section contents is retrieved
	successfully.  If the section has no contents then this function
	returns @code{TRUE} but @var{*ptr} is set to NULL.
*/

bfd_boolean
bfd_get_full_section_contents (bfd *abfd, sec_ptr sec, bfd_byte **ptr)
{
  bfd_size_type sz;
  bfd_byte *p = *ptr;
  bfd_boolean ret;
  bfd_size_type save_size;
  bfd_size_type save_rawsize;
  bfd_byte *compressed_buffer;

  if (abfd->direction != write_direction && sec->rawsize != 0)
    sz = sec->rawsize;
  else
    sz = sec->size;
  if (sz == 0)
    {
      *ptr = NULL;
      return TRUE;
    }

  switch (sec->compress_status)
    {
    case COMPRESS_SECTION_NONE:
      if (p == NULL)
	{
	  p = (bfd_byte *) bfd_malloc (sz);
	  if (p == NULL)
	    return FALSE;
	}

      if (!bfd_get_section_contents (abfd, sec, p, 0, sz))
	{
	  if (*ptr != p)
	    free (p);
	  return FALSE;
	}
      *ptr = p;
      return TRUE;

    case DECOMPRESS_SECTION_SIZED:
      /* Read in the full compressed section contents.  */
      compressed_buffer = (bfd_byte *) bfd_malloc (sec->compressed_size);
      if (compressed_buffer == NULL)
	return FALSE;
      save_rawsize = sec->rawsize;
      save_size = sec->size;
      /* Clear rawsize, set size to compressed size and set compress_status
	 to COMPRESS_SECTION_NONE.  If the compressed size is bigger than
	 the uncompressed size, bfd_get_section_contents will fail.  */
      sec->rawsize = 0;
      sec->size = sec->compressed_size;
      sec->compress_status = COMPRESS_SECTION_NONE;
      ret = bfd_get_section_contents (abfd, sec, compressed_buffer,
				      0, sec->compressed_size);
      /* Restore rawsize and size.  */
      sec->rawsize = save_rawsize;
      sec->size = save_size;
      sec->compress_status = DECOMPRESS_SECTION_SIZED;
      if (!ret)
	goto fail_compressed;

      if (p == NULL)
	p = (bfd_byte *) bfd_malloc (sz);
      if (p == NULL)
	goto fail_compressed;

      if (!decompress_contents (compressed_buffer, sec->compressed_size, p, sz))
	{
	  bfd_set_error (bfd_error_bad_value);
	  if (p != *ptr)
	    free (p);
	fail_compressed:
	  free (compressed_buffer);
	  return FALSE;
	}

      free (compressed_buffer);
      *ptr = p;
      return TRUE;

    case COMPRESS_SECTION_DONE:
      if (sec->contents == NULL)
	return FALSE;
      if (p == NULL)
	{
	  p = (bfd_byte *) bfd_malloc (sz);
	  if (p == NULL)
	    return FALSE;
	  *ptr = p;
	}
      /* PR 17512; file: 5bc29788.  */
      if (p != sec->contents)
	memcpy (p, sec->contents, sz);
      return TRUE;

    default:
      abort ();
    }
}

/*
FUNCTION
	bfd_cache_section_contents

SYNOPSIS
	void bfd_cache_section_contents
	  (asection *sec, void *contents);

DESCRIPTION
	Stash @var(contents) so any following reads of @var(sec) do
	not need to decompress again.
*/

void
bfd_cache_section_contents (asection *sec, void *contents)
{
  if (sec->compress_status == DECOMPRESS_SECTION_SIZED)
    sec->compress_status = COMPRESS_SECTION_DONE;
  sec->contents = contents;
  sec->flags |= SEC_IN_MEMORY;
}


/*
FUNCTION
	bfd_is_section_compressed

SYNOPSIS
	bfd_boolean bfd_is_section_compressed
	  (bfd *abfd, asection *section);

DESCRIPTION
	Return @code{TRUE} if @var{section} is compressed.
*/

bfd_boolean
bfd_is_section_compressed (bfd *abfd, sec_ptr sec)
{
  bfd_byte compressed_buffer [12];
  unsigned int saved = sec->compress_status;
  bfd_boolean compressed;

  /* Don't decompress the section.  */
  sec->compress_status = COMPRESS_SECTION_NONE;

  /* Read the zlib header.  In this case, it should be "ZLIB" followed
     by the uncompressed section size, 8 bytes in big-endian order.  */
  compressed = (bfd_get_section_contents (abfd, sec, compressed_buffer, 0, 12)
		&& CONST_STRNEQ ((char*) compressed_buffer, "ZLIB"));

  /* Check for the pathalogical case of a debug string section that
     contains the string ZLIB.... as the first entry.  We assume that
     no uncompressed .debug_str section would ever be big enough to
     have the first byte of its (big-endian) size be non-zero.  */
  if (compressed
      && strcmp (sec->name, ".debug_str") == 0
      && ISPRINT (compressed_buffer[4]))
    compressed = FALSE;

  /* Restore compress_status.  */
  sec->compress_status = saved;
  return compressed;
}

/*
FUNCTION
	bfd_init_section_decompress_status

SYNOPSIS
	bfd_boolean bfd_init_section_decompress_status
	  (bfd *abfd, asection *section);

DESCRIPTION
	Record compressed section size, update section size with
	decompressed size and set compress_status to
	DECOMPRESS_SECTION_SIZED.

	Return @code{FALSE} if the section is not a valid compressed
	section or zlib is not installed on this machine.  Otherwise,
	return @code{TRUE}.
*/

bfd_boolean
bfd_init_section_decompress_status (bfd *abfd, sec_ptr sec)
{
  bfd_byte compressed_buffer [12];
  bfd_size_type uncompressed_size;

  if (sec->rawsize != 0
      || sec->contents != NULL
      || sec->compress_status != COMPRESS_SECTION_NONE
      || !bfd_get_section_contents (abfd, sec, compressed_buffer, 0, 12))
    {
      bfd_set_error (bfd_error_invalid_operation);
      return FALSE;
    }

  /* Read the zlib header.  In this case, it should be "ZLIB" followed
     by the uncompressed section size, 8 bytes in big-endian order.  */
  if (! CONST_STRNEQ ((char*) compressed_buffer, "ZLIB"))
    {
      bfd_set_error (bfd_error_wrong_format);
      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];

  sec->compressed_size = sec->size;
  sec->size = uncompressed_size;
  sec->compress_status = DECOMPRESS_SECTION_SIZED;

  return TRUE;
}

/*
FUNCTION
	bfd_init_section_compress_status

SYNOPSIS
	bfd_boolean bfd_init_section_compress_status
	  (bfd *abfd, asection *section);

DESCRIPTION
	If open for read, compress section, update section size with
	compressed size and set compress_status to COMPRESS_SECTION_DONE.

	Return @code{FALSE} if the section is not a valid compressed
	section or zlib is not installed on this machine.  Otherwise,
	return @code{TRUE}.
*/

bfd_boolean
bfd_init_section_compress_status (bfd *abfd, sec_ptr sec)
{
  bfd_size_type uncompressed_size;
  bfd_byte *uncompressed_buffer;
  bfd_boolean ret;

  /* Error if not opened for read.  */
  if (abfd->direction != read_direction
      || sec->size == 0
      || sec->rawsize != 0
      || sec->contents != NULL
      || sec->compress_status != COMPRESS_SECTION_NONE)
    {
      bfd_set_error (bfd_error_invalid_operation);
      return FALSE;
    }

  /* Read in the full section contents and compress it.  */
  uncompressed_size = sec->size;
  uncompressed_buffer = (bfd_byte *) bfd_malloc (uncompressed_size);
  if (!bfd_get_section_contents (abfd, sec, uncompressed_buffer,
				 0, uncompressed_size))
    ret = FALSE;
  else
    ret = bfd_compress_section_contents (abfd, sec,
					 uncompressed_buffer,
					 uncompressed_size);

  return ret;
}
Commit	Line	Data
0acf065b	1	/* Compressed section support (intended for debug sections).
b90efa5b	2	Copyright (C) 2008-2015 Free Software Foundation, Inc.
1b315056 CS	3
	4	This file is part of BFD, the Binary File Descriptor library.
	5
	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.
	10
	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.
	15
	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. */
	20
1b315056	21	#include "sysdep.h"
243340ad	22	#include <zlib.h>
1b315056 CS	23	#include "bfd.h"
1b315056 CS	24	#include "libbfd.h"
a953eec9	25	#include "safe-ctype.h"
1b315056	26
4a114e3e L	27	static bfd_boolean
	28	decompress_contents (bfd_byte *compressed_buffer,
	29	bfd_size_type compressed_size,
	30	bfd_byte *uncompressed_buffer,
	31	bfd_size_type uncompressed_size)
	32	{
	33	z_stream strm;
	34	int rc;
	35
	36	/* It is possible the section consists of several compressed
	37	buffers concatenated together, so we uncompress in a loop. */
	38	strm.zalloc = NULL;
	39	strm.zfree = NULL;
	40	strm.opaque = NULL;
	41	strm.avail_in = compressed_size - 12;
	42	strm.next_in = (Bytef*) compressed_buffer + 12;
	43	strm.avail_out = uncompressed_size;
	44
a253d456	45	BFD_ASSERT (Z_OK == 0);
4a114e3e	46	rc = inflateInit (&strm);
a29a8af8	47	while (strm.avail_in > 0 && strm.avail_out > 0)
4a114e3e L	48	{
4a114e3e L	49	if (rc != Z_OK)
a253d456	50	break;
4a114e3e L	51	strm.next_out = ((Bytef*) uncompressed_buffer
	52	+ (uncompressed_size - strm.avail_out));
	53	rc = inflate (&strm, Z_FINISH);
	54	if (rc != Z_STREAM_END)
a253d456	55	break;
4a114e3e L	56	rc = inflateReset (&strm);
4a114e3e L	57	}
a253d456	58	rc \|= inflateEnd (&strm);
82c6068a	59	return rc == Z_OK && strm.avail_out == 0;
4a114e3e	60	}
4a114e3e	61
0b0732e1 L	62	/* Compress data of the size specified in @var{uncompressed_size}
	63	and pointed to by @var{uncompressed_buffer} using zlib and store
	64	as the contents field. This function assumes the contents
	65	field was allocated using bfd_malloc() or equivalent. If zlib
	66	is not installed on this machine, the input is unmodified.
1b315056	67
0b0732e1 L	68	Return @code{TRUE} if the full section contents is compressed
0b0732e1 L	69	successfully. */
1b315056	70
0b0732e1	71	static bfd_boolean
243340ad L	72	bfd_compress_section_contents (bfd *abfd ATTRIBUTE_UNUSED, sec_ptr sec,
	73	bfd_byte *uncompressed_buffer,
	74	bfd_size_type uncompressed_size)
1b315056	75	{
ae6a0217	76	uLong compressed_size;
4a114e3e L	77	bfd_byte *compressed_buffer;
	78
	79	compressed_size = compressBound (uncompressed_size) + 12;
	80	compressed_buffer = (bfd_byte *) bfd_malloc (compressed_size);
	81
4281caad MS	82	if (compressed_buffer == NULL)
	83	return FALSE;
	84
4a114e3e L	85	if (compress ((Bytef*) compressed_buffer + 12,
	86	&compressed_size,
	87	(const Bytef*) uncompressed_buffer,
	88	uncompressed_size) != Z_OK)
	89	{
	90	free (compressed_buffer);
	91	bfd_set_error (bfd_error_bad_value);
	92	return FALSE;
	93	}
	94
4a114e3e L	95	compressed_size += 12;
4a114e3e L	96
8d001214 L	97	/* PR binutils/18087: If compression didn't make the section smaller,
	98	just keep it uncompressed. */
	99	if (compressed_size < uncompressed_size)
	100	{
	101	/* Write the zlib header. In this case, it should be "ZLIB" followed
	102	by the uncompressed section size, 8 bytes in big-endian order. */
	103	memcpy (compressed_buffer, "ZLIB", 4);
	104	compressed_buffer[11] = uncompressed_size; uncompressed_size >>= 8;
	105	compressed_buffer[10] = uncompressed_size; uncompressed_size >>= 8;
	106	compressed_buffer[9] = uncompressed_size; uncompressed_size >>= 8;
	107	compressed_buffer[8] = uncompressed_size; uncompressed_size >>= 8;
	108	compressed_buffer[7] = uncompressed_size; uncompressed_size >>= 8;
	109	compressed_buffer[6] = uncompressed_size; uncompressed_size >>= 8;
	110	compressed_buffer[5] = uncompressed_size; uncompressed_size >>= 8;
	111	compressed_buffer[4] = uncompressed_size;
	112
	113	free (uncompressed_buffer);
	114	sec->contents = compressed_buffer;
	115	sec->size = compressed_size;
	116	sec->compress_status = COMPRESS_SECTION_DONE;
	117	}
	118	else
	119	{
	120	sec->contents = uncompressed_buffer;
	121	sec->compress_status = COMPRESS_SECTION_NONE;
	122	}
4a114e3e L	123
4a114e3e L	124	return TRUE;
4a114e3e L	125	}
	126
	127	/*
	128	FUNCTION
	129	bfd_get_full_section_contents
	130
	131	SYNOPSIS
	132	bfd_boolean bfd_get_full_section_contents
	133	(bfd abfd, asection section, bfd_byte **ptr);
	134
	135	DESCRIPTION
	136	Read all data from @var{section} in BFD @var{abfd}, decompress
	137	if needed, and store in @var{ptr}. If @var{ptr} is NULL,
68ffbac6	138	return @var{*ptr} with memory malloc'd by this function.
4a114e3e L	139
4a114e3e L	140	Return @code{TRUE} if the full section contents is retrieved
06614111 NC	141	successfully. If the section has no contents then this function
06614111 NC	142	returns @code{TRUE} but @var{*ptr} is set to NULL.
4a114e3e L	143	*/
	144
	145	bfd_boolean
	146	bfd_get_full_section_contents (bfd abfd, sec_ptr sec, bfd_byte *ptr)
	147	{
e57278ef	148	bfd_size_type sz;
4a114e3e	149	bfd_byte p = ptr;
82c6068a	150	bfd_boolean ret;
38b774d2 AM	151	bfd_size_type save_size;
38b774d2 AM	152	bfd_size_type save_rawsize;
4a114e3e	153	bfd_byte *compressed_buffer;
4a114e3e	154
e57278ef AM	155	if (abfd->direction != write_direction && sec->rawsize != 0)
	156	sz = sec->rawsize;
	157	else
	158	sz = sec->size;
4a114e3e	159	if (sz == 0)
06614111 NC	160	{
	161	*ptr = NULL;
	162	return TRUE;
	163	}
4a114e3e L	164
	165	switch (sec->compress_status)
	166	{
	167	case COMPRESS_SECTION_NONE:
	168	if (p == NULL)
	169	{
0d13c96b	170	p = (bfd_byte *) bfd_malloc (sz);
4a114e3e L	171	if (p == NULL)
4a114e3e L	172	return FALSE;
4a114e3e	173	}
06614111	174
82c6068a AM	175	if (!bfd_get_section_contents (abfd, sec, p, 0, sz))
	176	{
	177	if (*ptr != p)
	178	free (p);
	179	return FALSE;
	180	}
	181	*ptr = p;
4a114e3e L	182	return TRUE;
	183
	184	case DECOMPRESS_SECTION_SIZED:
82c6068a	185	/* Read in the full compressed section contents. */
38b774d2	186	compressed_buffer = (bfd_byte *) bfd_malloc (sec->compressed_size);
82c6068a AM	187	if (compressed_buffer == NULL)
82c6068a AM	188	return FALSE;
38b774d2 AM	189	save_rawsize = sec->rawsize;
38b774d2 AM	190	save_size = sec->size;
82c6068a AM	191	/* Clear rawsize, set size to compressed size and set compress_status
	192	to COMPRESS_SECTION_NONE. If the compressed size is bigger than
	193	the uncompressed size, bfd_get_section_contents will fail. */
	194	sec->rawsize = 0;
38b774d2	195	sec->size = sec->compressed_size;
82c6068a AM	196	sec->compress_status = COMPRESS_SECTION_NONE;
82c6068a AM	197	ret = bfd_get_section_contents (abfd, sec, compressed_buffer,
38b774d2	198	0, sec->compressed_size);
82c6068a	199	/* Restore rawsize and size. */
38b774d2 AM	200	sec->rawsize = save_rawsize;
38b774d2 AM	201	sec->size = save_size;
4a114e3e	202	sec->compress_status = DECOMPRESS_SECTION_SIZED;
82c6068a AM	203	if (!ret)
82c6068a AM	204	goto fail_compressed;
4a114e3e	205
38b774d2 AM	206	if (p == NULL)
	207	p = (bfd_byte *) bfd_malloc (sz);
	208	if (p == NULL)
4a114e3e	209	goto fail_compressed;
4a114e3e	210
38b774d2	211	if (!decompress_contents (compressed_buffer, sec->compressed_size, p, sz))
82c6068a AM	212	{
82c6068a AM	213	bfd_set_error (bfd_error_bad_value);
38b774d2 AM	214	if (p != *ptr)
38b774d2 AM	215	free (p);
82c6068a AM	216	fail_compressed:
	217	free (compressed_buffer);
	218	return FALSE;
	219	}
4a114e3e	220
82c6068a	221	free (compressed_buffer);
38b774d2 AM	222	*ptr = p;
38b774d2 AM	223	return TRUE;
4a114e3e	224
82c6068a	225	case COMPRESS_SECTION_DONE:
db6b071a NC	226	if (sec->contents == NULL)
db6b071a NC	227	return FALSE;
82c6068a AM	228	if (p == NULL)
	229	{
	230	p = (bfd_byte *) bfd_malloc (sz);
	231	if (p == NULL)
	232	return FALSE;
	233	*ptr = p;
	234	}
06614111 NC	235	/* PR 17512; file: 5bc29788. */
	236	if (p != sec->contents)
	237	memcpy (p, sec->contents, sz);
82c6068a	238	return TRUE;
4a114e3e	239
82c6068a AM	240	default:
	241	abort ();
	242	}
4a114e3e L	243	}
4a114e3e L	244
8a72cc6e AM	245	/*
	246	FUNCTION
	247	bfd_cache_section_contents
	248
	249	SYNOPSIS
	250	void bfd_cache_section_contents
	251	(asection sec, void contents);
	252
	253	DESCRIPTION
	254	Stash @var(contents) so any following reads of @var(sec) do
	255	not need to decompress again.
	256	*/
	257
	258	void
	259	bfd_cache_section_contents (asection sec, void contents)
	260	{
	261	if (sec->compress_status == DECOMPRESS_SECTION_SIZED)
	262	sec->compress_status = COMPRESS_SECTION_DONE;
	263	sec->contents = contents;
	264	sec->flags \|= SEC_IN_MEMORY;
	265	}
	266
	267
4a114e3e L	268	/*
	269	FUNCTION
	270	bfd_is_section_compressed
	271
	272	SYNOPSIS
	273	bfd_boolean bfd_is_section_compressed
	274	(bfd abfd, asection section);
	275
	276	DESCRIPTION
	277	Return @code{TRUE} if @var{section} is compressed.
	278	*/
	279
	280	bfd_boolean
	281	bfd_is_section_compressed (bfd *abfd, sec_ptr sec)
	282	{
	283	bfd_byte compressed_buffer [12];
64f40162 L	284	unsigned int saved = sec->compress_status;
	285	bfd_boolean compressed;
	286
	287	/* Don't decompress the section. */
	288	sec->compress_status = COMPRESS_SECTION_NONE;
4a114e3e L	289
	290	/* Read the zlib header. In this case, it should be "ZLIB" followed
	291	by the uncompressed section size, 8 bytes in big-endian order. */
64f40162 L	292	compressed = (bfd_get_section_contents (abfd, sec, compressed_buffer, 0, 12)
	293	&& CONST_STRNEQ ((char*) compressed_buffer, "ZLIB"));
	294
a953eec9 NC	295	/* Check for the pathalogical case of a debug string section that
	296	contains the string ZLIB.... as the first entry. We assume that
	297	no uncompressed .debug_str section would ever be big enough to
	298	have the first byte of its (big-endian) size be non-zero. */
	299	if (compressed
	300	&& strcmp (sec->name, ".debug_str") == 0
	301	&& ISPRINT (compressed_buffer[4]))
	302	compressed = FALSE;
	303
64f40162 L	304	/* Restore compress_status. */
	305	sec->compress_status = saved;
	306	return compressed;
4a114e3e L	307	}
	308
	309	/*
	310	FUNCTION
	311	bfd_init_section_decompress_status
	312
	313	SYNOPSIS
	314	bfd_boolean bfd_init_section_decompress_status
	315	(bfd abfd, asection section);
	316
	317	DESCRIPTION
	318	Record compressed section size, update section size with
	319	decompressed size and set compress_status to
	320	DECOMPRESS_SECTION_SIZED.
	321
	322	Return @code{FALSE} if the section is not a valid compressed
	323	section or zlib is not installed on this machine. Otherwise,
	324	return @code{TRUE}.
	325	*/
	326
	327	bfd_boolean
243340ad	328	bfd_init_section_decompress_status (bfd *abfd, sec_ptr sec)
4a114e3e	329	{
4a114e3e L	330	bfd_byte compressed_buffer [12];
	331	bfd_size_type uncompressed_size;
	332
	333	if (sec->rawsize != 0
	334	\|\| sec->contents != NULL
	335	\|\| sec->compress_status != COMPRESS_SECTION_NONE
	336	\|\| !bfd_get_section_contents (abfd, sec, compressed_buffer, 0, 12))
	337	{
	338	bfd_set_error (bfd_error_invalid_operation);
	339	return FALSE;
	340	}
1b315056 CS	341
	342	/* Read the zlib header. In this case, it should be "ZLIB" followed
	343	by the uncompressed section size, 8 bytes in big-endian order. */
4a114e3e L	344	if (! CONST_STRNEQ ((char*) compressed_buffer, "ZLIB"))
	345	{
	346	bfd_set_error (bfd_error_wrong_format);
	347	return FALSE;
	348	}
	349
1b315056 CS	350	uncompressed_size = compressed_buffer[4]; uncompressed_size <<= 8;
	351	uncompressed_size += compressed_buffer[5]; uncompressed_size <<= 8;
	352	uncompressed_size += compressed_buffer[6]; uncompressed_size <<= 8;
	353	uncompressed_size += compressed_buffer[7]; uncompressed_size <<= 8;
	354	uncompressed_size += compressed_buffer[8]; uncompressed_size <<= 8;
	355	uncompressed_size += compressed_buffer[9]; uncompressed_size <<= 8;
	356	uncompressed_size += compressed_buffer[10]; uncompressed_size <<= 8;
	357	uncompressed_size += compressed_buffer[11];
	358
4a114e3e L	359	sec->compressed_size = sec->size;
	360	sec->size = uncompressed_size;
	361	sec->compress_status = DECOMPRESS_SECTION_SIZED;
1b315056	362
4a114e3e	363	return TRUE;
4a114e3e L	364	}
	365
	366	/*
	367	FUNCTION
	368	bfd_init_section_compress_status
	369
	370	SYNOPSIS
	371	bfd_boolean bfd_init_section_compress_status
	372	(bfd abfd, asection section);
	373
	374	DESCRIPTION
	375	If open for read, compress section, update section size with
	376	compressed size and set compress_status to COMPRESS_SECTION_DONE.
	377
	378	Return @code{FALSE} if the section is not a valid compressed
	379	section or zlib is not installed on this machine. Otherwise,
	380	return @code{TRUE}.
	381	*/
	382
	383	bfd_boolean
243340ad	384	bfd_init_section_compress_status (bfd *abfd, sec_ptr sec)
4a114e3e	385	{
4a114e3e L	386	bfd_size_type uncompressed_size;
	387	bfd_byte *uncompressed_buffer;
	388	bfd_boolean ret;
	389
	390	/* Error if not opened for read. */
	391	if (abfd->direction != read_direction
	392	\|\| sec->size == 0
	393	\|\| sec->rawsize != 0
	394	\|\| sec->contents != NULL
	395	\|\| sec->compress_status != COMPRESS_SECTION_NONE)
1b315056	396	{
4a114e3e L	397	bfd_set_error (bfd_error_invalid_operation);
4a114e3e L	398	return FALSE;
1b315056	399	}
1b315056	400
4a114e3e L	401	/* Read in the full section contents and compress it. */
	402	uncompressed_size = sec->size;
	403	uncompressed_buffer = (bfd_byte *) bfd_malloc (uncompressed_size);
	404	if (!bfd_get_section_contents (abfd, sec, uncompressed_buffer,
	405	0, uncompressed_size))
	406	ret = FALSE;
	407	else
	408	ret = bfd_compress_section_contents (abfd, sec,
	409	uncompressed_buffer,
	410	uncompressed_size);
1b315056	411
4a114e3e	412	return ret;
1b315056	413	}