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authorH.J. Lu <hjl.tools@gmail.com>2015-05-14 15:58:51 -0700
committerH.J. Lu <hjl.tools@gmail.com>2015-05-14 16:02:08 -0700
commitdab394de9e41de54df5e2310e081e1c550326f5b (patch)
treefbdbe4f564baa35e7fb4bea28416a531fcb9d916 /bfd/compress.c
parent61a7418ccb7c2de12d4c4df79e193f32db938a11 (diff)
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Don't add the zlib header to SHF_COMPRESSED section
In a SHF_COMPRESSED compressed section, the raw compressed data should begin immediately after the compression header. This patch removes the extra zlib header from the SHF_COMPRESSED section. bfd/ * bfd.c (bfd_update_compression_header): Also write the zlib header if the SHF_COMPRESSED bit cleared.. (bfd_check_compression_header): Return the uncompressed size. * compress.c (decompress_contents): Don't skip the zlib header. (bfd_compress_section_contents): Properly handle ELFCOMPRESS_ZLIB, which doesn't have the zlib header. (bfd_init_section_decompress_status): Likewise. (bfd_get_full_section_contents): Updated. (bfd_is_section_compressed): Likewise. (bfd_is_section_compressed_with_header): Return the uncompressed size. * elf.c (_bfd_elf_make_section_from_shdr): Updated. * bfd-in2.h: Regenerated. binutils/ * readelf.c (uncompress_section_contents): Add a parameter for uncompressed size. Don't check the zlib header. (load_specific_debug_section): Updated. binutils/testsuite/ * binutils-all/compress.exp: Replace "$OBJDUMP -s -j .debug_info" with "$OBJDUMP -W". * binutils-all/libdw2-compressedgabi.out: Updated. gas/ 2015-05-14 H.J. Lu <hongjiu.lu@intel.com> * write.c (compress_debug): Don't write the zlib header, which is handled by bfd_update_compression_header.
Diffstat (limited to 'bfd/compress.c')
-rw-r--r--bfd/compress.c157
1 files changed, 84 insertions, 73 deletions
diff --git a/bfd/compress.c b/bfd/compress.c
index 07289e5..7751948 100644
--- a/bfd/compress.c
+++ b/bfd/compress.c
@@ -43,8 +43,8 @@ decompress_contents (bfd_byte *compressed_buffer,
we first zero the entire z_stream structure and then set the fields
that we need. */
memset (& strm, 0, sizeof strm);
- strm.avail_in = compressed_size - 12;
- strm.next_in = (Bytef*) compressed_buffer + 12;
+ strm.avail_in = compressed_size;
+ strm.next_in = (Bytef*) compressed_buffer;
strm.avail_out = uncompressed_size;
BFD_ASSERT (Z_OK == 0);
@@ -81,18 +81,19 @@ bfd_compress_section_contents (bfd *abfd, sec_ptr sec,
bfd_byte *buffer;
bfd_size_type buffer_size;
bfd_boolean decompress;
-#if defined(__GNUC__) && GCC_VERSION < 4007
- /* Work around a GCC uninitialized warning bug fixed in GCC 4.7. */
int zlib_size = 0;
-#else
- int zlib_size;
-#endif
int orig_compression_header_size;
- int compression_header_size
- = bfd_get_compression_header_size (abfd, NULL);
+ bfd_size_type orig_uncompressed_size;
+ int header_size = bfd_get_compression_header_size (abfd, NULL);
bfd_boolean compressed
= bfd_is_section_compressed_with_header (abfd, sec,
- &orig_compression_header_size);
+ &orig_compression_header_size,
+ &orig_uncompressed_size);
+
+ /* Either ELF compression header or the 12-byte, "ZLIB" + 8-byte size,
+ overhead in .zdebug* section. */
+ if (!header_size)
+ header_size = 12;
if (compressed)
{
@@ -105,34 +106,34 @@ bfd_compress_section_contents (bfd *abfd, sec_ptr sec,
if (orig_compression_header_size == 0)
{
/* Convert it from .zdebug* section. Get the uncompressed
- size first. */
- zlib_size = uncompressed_size;
- compressed_size = zlib_size + compression_header_size;
- uncompressed_size = bfd_getb64 (uncompressed_buffer + 4);
+ size first. We need to substract the 12-byte overhead in
+ .zdebug* section. Set orig_compression_header_size to
+ the 12-bye overhead. */
+ orig_compression_header_size = 12;
+ zlib_size = uncompressed_size - 12;
}
else
{
- /* Convert it to .zdebug* section. */
+ /* Convert it to .zdebug* section. */
zlib_size = uncompressed_size - orig_compression_header_size;
- compressed_size = zlib_size;
}
+
+ /* Add the header size. */
+ compressed_size = zlib_size + header_size;
}
else
- compressed_size = compressBound (uncompressed_size) + 12;
+ compressed_size = compressBound (uncompressed_size) + header_size;
- /* When converting from .zdebug* section, uncompress if it leads to
- smaller size. */
- if (compressed
- && orig_compression_header_size == 0
- && compressed_size > uncompressed_size)
+ /* Uncompress if it leads to smaller size. */
+ if (compressed && compressed_size > orig_uncompressed_size)
{
decompress = TRUE;
- buffer_size = uncompressed_size;
+ buffer_size = orig_uncompressed_size;
}
else
{
decompress = FALSE;
- buffer_size = compressed_size + compression_header_size;
+ buffer_size = compressed_size;
}
buffer = (bfd_byte *) bfd_alloc (abfd, buffer_size);
if (buffer == NULL)
@@ -140,11 +141,12 @@ bfd_compress_section_contents (bfd *abfd, sec_ptr sec,
if (compressed)
{
- sec->size = uncompressed_size;
+ sec->size = orig_uncompressed_size;
if (decompress)
{
- if (!decompress_contents (uncompressed_buffer, zlib_size,
- buffer, uncompressed_size))
+ if (!decompress_contents (uncompressed_buffer
+ + orig_compression_header_size,
+ zlib_size, buffer, buffer_size))
{
bfd_set_error (bfd_error_bad_value);
bfd_release (abfd, buffer);
@@ -153,20 +155,18 @@ bfd_compress_section_contents (bfd *abfd, sec_ptr sec,
free (uncompressed_buffer);
sec->contents = buffer;
sec->compress_status = COMPRESS_SECTION_DONE;
- return uncompressed_size;
+ return orig_uncompressed_size;
}
else
{
bfd_update_compression_header (abfd, buffer, sec);
- memmove (buffer + compression_header_size,
+ memmove (buffer + header_size,
uncompressed_buffer + orig_compression_header_size,
zlib_size);
}
}
else
{
- bfd_size_type size = uncompressed_size;
- int header_size = 12 + compression_header_size;
if (compress ((Bytef*) buffer + header_size,
&compressed_size,
(const Bytef*) uncompressed_buffer,
@@ -181,15 +181,7 @@ bfd_compress_section_contents (bfd *abfd, sec_ptr sec,
/* PR binutils/18087: If compression didn't make the section smaller,
just keep it uncompressed. */
if (compressed_size < uncompressed_size)
- {
- bfd_update_compression_header (abfd, buffer, sec);
-
- /* Write the zlib header. In this case, it should be "ZLIB"
- followed by the uncompressed section size, 8 bytes in
- big-endian order. */
- memcpy (buffer + compression_header_size, "ZLIB", 4);
- bfd_putb64 (size, buffer + compression_header_size + 4);
- }
+ bfd_update_compression_header (abfd, buffer, sec);
else
{
/* NOTE: There is a small memory leak here since
@@ -295,6 +287,10 @@ bfd_get_full_section_contents (bfd *abfd, sec_ptr sec, bfd_byte **ptr)
goto fail_compressed;
compression_header_size = bfd_get_compression_header_size (abfd, sec);
+ if (compression_header_size == 0)
+ /* Set header size to the zlib header size if it is a
+ SHF_COMPRESSED section. */
+ compression_header_size = 12;
if (!decompress_contents (compressed_buffer + compression_header_size,
sec->compressed_size, p, sz))
{
@@ -359,49 +355,56 @@ FUNCTION
SYNOPSIS
bfd_boolean bfd_is_section_compressed_with_header
(bfd *abfd, asection *section,
- int *compression_header_size_p);
+ int *compression_header_size_p,
+ bfd_size_type *uncompressed_size_p);
DESCRIPTION
Return @code{TRUE} if @var{section} is compressed. Compression
- header size is returned in @var{compression_header_size_p}. If
+ header size is returned in @var{compression_header_size_p} and
+ uncompressed size is returned in @var{uncompressed_size_p}. If
compression is unsupported, compression header size is returned
- with -1.
+ with -1 and uncompressed size is returned with 0.
*/
bfd_boolean
bfd_is_section_compressed_with_header (bfd *abfd, sec_ptr sec,
- int *compression_header_size_p)
+ int *compression_header_size_p,
+ bfd_size_type *uncompressed_size_p)
{
- bfd_byte header[MAX_COMPRESSION_HEADER_SIZE + 12];
+ bfd_byte header[MAX_COMPRESSION_HEADER_SIZE];
int compression_header_size;
- int header_size = 12;
+ int header_size;
unsigned int saved = sec->compress_status;
bfd_boolean compressed;
compression_header_size = bfd_get_compression_header_size (abfd, sec);
if (compression_header_size > MAX_COMPRESSION_HEADER_SIZE)
abort ();
- header_size += compression_header_size;
+ header_size = compression_header_size ? compression_header_size : 12;
/* 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, header, 0,
- header_size)
- && CONST_STRNEQ ((char*) header + compression_header_size,
- "ZLIB");
+ /* Read the header. */
+ if (bfd_get_section_contents (abfd, sec, header, 0, header_size))
+ {
+ if (compression_header_size == 0)
+ /* In this case, it should be "ZLIB" followed by the uncompressed
+ section size, 8 bytes in big-endian order. */
+ compressed = CONST_STRNEQ ((char*) header , "ZLIB");
+ else
+ compressed = TRUE;
+ }
+ else
+ compressed = FALSE;
+ *uncompressed_size_p = sec->size;
if (compressed)
{
if (compression_header_size != 0)
{
- bfd_size_type uncompressed_size
- = bfd_getb64 ((bfd_byte *) header
- + compression_header_size + 4);
if (!bfd_check_compression_header (abfd, header, sec,
- uncompressed_size))
+ uncompressed_size_p))
compression_header_size = -1;
}
/* Check for the pathalogical case of a debug string section that
@@ -409,8 +412,10 @@ bfd_is_section_compressed_with_header (bfd *abfd, sec_ptr sec,
no uncompressed .debug_str section would ever be big enough to
have the first byte of its (big-endian) size be non-zero. */
else if (strcmp (sec->name, ".debug_str") == 0
- && ISPRINT (header[compression_header_size + 4]))
+ && ISPRINT (header[4]))
compressed = FALSE;
+ else
+ *uncompressed_size_p = bfd_getb64 (header + 4);
}
/* Restore compress_status. */
@@ -435,9 +440,12 @@ bfd_boolean
bfd_is_section_compressed (bfd *abfd, sec_ptr sec)
{
int compression_header_size;
+ bfd_size_type uncompressed_size;
return (bfd_is_section_compressed_with_header (abfd, sec,
- &compression_header_size)
- && compression_header_size >= 0);
+ &compression_header_size,
+ &uncompressed_size)
+ && compression_header_size >= 0
+ && uncompressed_size > 0);
}
/*
@@ -460,16 +468,17 @@ DESCRIPTION
bfd_boolean
bfd_init_section_decompress_status (bfd *abfd, sec_ptr sec)
{
- bfd_byte header[MAX_COMPRESSION_HEADER_SIZE + 12];
+ bfd_byte header[MAX_COMPRESSION_HEADER_SIZE];
int compression_header_size;
- int header_size = 12;
+ int header_size;
bfd_size_type uncompressed_size;
compression_header_size = bfd_get_compression_header_size (abfd, sec);
if (compression_header_size > MAX_COMPRESSION_HEADER_SIZE)
abort ();
- header_size += compression_header_size;
+ header_size = compression_header_size ? compression_header_size : 12;
+ /* Read the header. */
if (sec->rawsize != 0
|| sec->contents != NULL
|| sec->compress_status != COMPRESS_SECTION_NONE
@@ -479,22 +488,24 @@ bfd_init_section_decompress_status (bfd *abfd, sec_ptr sec)
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*) header + compression_header_size, "ZLIB"))
+ if (compression_header_size == 0)
{
- bfd_set_error (bfd_error_wrong_format);
- return FALSE;
+ /* In this case, it should be "ZLIB" followed by the uncompressed
+ section size, 8 bytes in big-endian order. */
+ if (! CONST_STRNEQ ((char*) header, "ZLIB"))
+ {
+ bfd_set_error (bfd_error_wrong_format);
+ return FALSE;
+ }
+ uncompressed_size = bfd_getb64 (header + 4);
}
-
- uncompressed_size = bfd_getb64 (header + compression_header_size + 4);
- if (compression_header_size != 0
- && !bfd_check_compression_header (abfd, header, sec,
- uncompressed_size))
+ else if (!bfd_check_compression_header (abfd, header, sec,
+ &uncompressed_size))
{
bfd_set_error (bfd_error_wrong_format);
return FALSE;
}
+
sec->compressed_size = sec->size;
sec->size = uncompressed_size;
sec->compress_status = DECOMPRESS_SECTION_SIZED;