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authorH.J. Lu <hjl.tools@gmail.com>2015-04-08 07:53:54 -0700
committerH.J. Lu <hjl.tools@gmail.com>2015-04-08 07:54:09 -0700
commit151411f8af16723a12e0e0eedc1ecdbea648c1b0 (patch)
treec1e9bd46096b7c153f60c144429f6ba52d07fa43 /bfd/compress.c
parentbfcf0ccd0131621213c5d6f2908cd703a90176f7 (diff)
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Add SHF_COMPRESSED support to gas and objcopy
This patch adds --compress-debug-sections={none|zlib|zlib-gnu|zlib-gabi} options to gas and objcopy for ELF files. They control how DWARF debug sections are compressed. --compress-debug-sections=none is equivalent to --nocompress-debug-sections. --compress-debug-sections=zlib and --compress-debug-sections=zlib-gnu are equivalent to --compress-debug-sections. --compress-debug-sections=zlib-gabi compresses DWARF debug sections with SHF_COMPRESSED from the ELF ABI. No linker changes are required to support SHF_COMPRESSED. bfd/ * archive.c (_bfd_get_elt_at_filepos): Also copy BFD_COMPRESS_GABI bit. * bfd.c (bfd::flags): Increase size to 18 bits. (BFD_COMPRESS_GABI): New. (BFD_FLAGS_SAVED): Add BFD_COMPRESS_GABI. (BFD_FLAGS_FOR_BFD_USE_MASK): Likewise. (bfd_update_compression_header): New fuction. (bfd_check_compression_header): Likewise. (bfd_get_compression_header_size): Likewise. (bfd_is_section_compressed_with_header): Likewise. * compress.c (MAX_COMPRESSION_HEADER_SIZE): New. (bfd_compress_section_contents): Return the uncompressed size if the full section contents is compressed successfully. Support converting from/to .zdebug* sections. (bfd_get_full_section_contents): Call bfd_get_compression_header_size to get compression header size. (bfd_is_section_compressed): Renamed to ... (bfd_is_section_compressed_with_header): This. Add a pointer argument to return compression header size. (bfd_is_section_compressed): Use it. (bfd_init_section_decompress_status): Call bfd_get_compression_header_size to get compression header size. Return FALSE if uncompressed section size is 0. * elf.c (_bfd_elf_make_section_from_shdr): Support converting from/to .zdebug* sections. * bfd-in2.h: Regenerated. binutils/ * objcopy.c (do_debug_sections): Add compress_zlib, compress_gnu_zlib and compress_gabi_zlib. (copy_options): Use optional_argument on compress-debug-sections. (copy_usage): Update --compress-debug-sections. (copy_file): Handle compress_zlib, compress_gnu_zlib and compress_gabi_zlib. (copy_main): Handle --compress-debug-sections={none|zlib|zlib-gnu|zlib-gabi}. * doc/binutils.texi: Document --compress-debug-sections={none|zlib|zlib-gnu|zlib-gabi}. binutils/testsuite/ * compress.exp: Add tests for --compress-debug-sections={none|zlib|zlib-gnu|zlib-gabi}. * binutils-all/dw2-3.rS: New file. * binutils-all/dw2-3.rt: Likewise. * binutils-all/libdw2-compressedgabi.out: Likewise. gas/ * as.c (show_usage): Update --compress-debug-sections. (std_longopts): Use optional_argument on compress-debug-sections. (parse_args): Handle --compress-debug-sections={none|zlib|zlib-gnu|zlib-gabi}. * as.h (compressed_debug_section_type): New. (flag_compress_debug): Change type to compressed_debug_section_type. --compress-debug-sections={none|zlib|zlib-gnu|zlib-gabi}. * write.c (compress_debug): Set BFD_COMPRESS_GABI for --compress-debug-sections=zlib-gabi. Call bfd_get_compression_header_size to get compression header size. Don't rename section name for --compress-debug-sections=zlib-gabi. * config/tc-i386.c (compressed_debug_section_type): Set to COMPRESS_DEBUG_ZLIB. * doc/as.texinfo: Document --compress-debug-sections={none|zlib|zlib-gnu|zlib-gabi}. gas/testsuite/ * gas/i386/dw2-compressed-1.d: New file. * gas/i386/dw2-compressed-2.d: Likewise. * gas/i386/dw2-compressed-3.d: Likewise. * gas/i386/x86-64-dw2-compressed-2.d: Likewise. * gas/i386/i386.exp: Run dw2-compressed-2, dw2-compressed-1, dw2-compressed-3 and x86-64-dw2-compressed-2. ld/testsuite/ * ld-elf/compress.exp: Add a test for --compress-debug-sections=zlib-gabi. (build_tests): Add 2 tests for --compress-debug-sections=zlib-gabi. (run_tests): Likewise. Verify linker output with zlib-gabi compressed debug input. * ld-elf/compressed1a.d: New file. * ld-elf/compressed1b.d: Likewise. * ld-elf/compressed1c.d: Likewise.
Diffstat (limited to 'bfd/compress.c')
-rw-r--r--bfd/compress.c265
1 files changed, 207 insertions, 58 deletions
diff --git a/bfd/compress.c b/bfd/compress.c
index b57650f..ba9fc96 100644
--- a/bfd/compress.c
+++ b/bfd/compress.c
@@ -24,6 +24,8 @@
#include "libbfd.h"
#include "safe-ctype.h"
+#define MAX_COMPRESSION_HEADER_SIZE 24
+
static bfd_boolean
decompress_contents (bfd_byte *compressed_buffer,
bfd_size_type compressed_size,
@@ -65,55 +67,136 @@ decompress_contents (bfd_byte *compressed_buffer,
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. */
+ Return the uncompressed size if the full section contents is
+ compressed successfully. Otherwise return 0. */
-static bfd_boolean
-bfd_compress_section_contents (bfd *abfd ATTRIBUTE_UNUSED, sec_ptr sec,
+static bfd_size_type
+bfd_compress_section_contents (bfd *abfd, 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);
+ bfd_byte *buffer;
+ bfd_size_type buffer_size;
+ bfd_boolean decompress;
+ int zlib_size;
+ int orig_compression_header_size;
+ int compression_header_size
+ = bfd_get_compression_header_size (abfd, NULL);
+ bfd_boolean compressed
+ = bfd_is_section_compressed_with_header (abfd, sec,
+ &orig_compression_header_size);
+
+ if (compressed)
+ {
+ /* We shouldn't decompress unsupported compressed section. */
+ if (orig_compression_header_size < 0)
+ abort ();
- if (compressed_buffer == NULL)
- return FALSE;
+ /* Different compression schemes. Just move the compressed section
+ contents to the right position. */
+ 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);
+ }
+ else
+ {
+ /* Convert it to .zdebug* section. */
+ zlib_size = uncompressed_size - orig_compression_header_size;
+ compressed_size = zlib_size;
+ }
+ }
+ else
+ compressed_size = compressBound (uncompressed_size) + 12;
- if (compress ((Bytef*) compressed_buffer + 12,
- &compressed_size,
- (const Bytef*) uncompressed_buffer,
- uncompressed_size) != Z_OK)
+ /* When converting from .zdebug* section, uncompress if it leads to
+ smaller size. */
+ if (compressed
+ && orig_compression_header_size == 0
+ && compressed_size > uncompressed_size)
{
- free (compressed_buffer);
- bfd_set_error (bfd_error_bad_value);
- return FALSE;
+ decompress = TRUE;
+ buffer_size = uncompressed_size;
}
+ else
+ {
+ decompress = FALSE;
+ buffer_size = compressed_size + compression_header_size;
+ }
+ buffer = (bfd_byte *) bfd_malloc (buffer_size);
+ if (buffer == NULL)
+ return 0;
- compressed_size += 12;
-
- /* PR binutils/18087: If compression didn't make the section smaller,
- just keep it uncompressed. */
- if (compressed_size < uncompressed_size)
+ if (compressed)
{
- /* 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);
- bfd_putb64 (uncompressed_size, compressed_buffer + 4);
- free (uncompressed_buffer);
- sec->contents = compressed_buffer;
- sec->size = compressed_size;
- sec->compress_status = COMPRESS_SECTION_DONE;
+ sec->size = uncompressed_size;
+ if (decompress)
+ {
+ if (!decompress_contents (uncompressed_buffer, zlib_size,
+ buffer, uncompressed_size))
+ {
+ bfd_set_error (bfd_error_bad_value);
+ free (buffer);
+ return 0;
+ }
+ free (uncompressed_buffer);
+ sec->contents = buffer;
+ sec->compress_status = COMPRESS_SECTION_DONE;
+ return uncompressed_size;
+ }
+ else
+ {
+ bfd_update_compression_header (abfd, buffer, sec);
+ memmove (buffer + compression_header_size,
+ uncompressed_buffer + orig_compression_header_size,
+ zlib_size);
+ }
}
else
{
- sec->contents = uncompressed_buffer;
- sec->compress_status = COMPRESS_SECTION_NONE;
+ 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,
+ uncompressed_size) != Z_OK)
+ {
+ free (buffer);
+ bfd_set_error (bfd_error_bad_value);
+ return 0;
+ }
+
+ compressed_size += header_size;
+ /* 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);
+ }
+ else
+ {
+ sec->contents = uncompressed_buffer;
+ sec->compress_status = COMPRESS_SECTION_NONE;
+ return uncompressed_size;
+ }
}
- return TRUE;
+ free (uncompressed_buffer);
+ sec->contents = buffer;
+ sec->size = compressed_size;
+ sec->compress_status = COMPRESS_SECTION_DONE;
+
+ return uncompressed_size;
}
/*
@@ -143,6 +226,7 @@ bfd_get_full_section_contents (bfd *abfd, sec_ptr sec, bfd_byte **ptr)
bfd_size_type save_size;
bfd_size_type save_rawsize;
bfd_byte *compressed_buffer;
+ unsigned int compression_header_size;
if (abfd->direction != write_direction && sec->rawsize != 0)
sz = sec->rawsize;
@@ -200,7 +284,9 @@ bfd_get_full_section_contents (bfd *abfd, sec_ptr sec, bfd_byte **ptr)
if (p == NULL)
goto fail_compressed;
- if (!decompress_contents (compressed_buffer, sec->compressed_size, p, sz))
+ compression_header_size = bfd_get_compression_header_size (abfd, sec);
+ if (!decompress_contents (compressed_buffer + compression_header_size,
+ sec->compressed_size, p, sz))
{
bfd_set_error (bfd_error_bad_value);
if (p != *ptr)
@@ -256,50 +342,96 @@ bfd_cache_section_contents (asection *sec, void *contents)
sec->flags |= SEC_IN_MEMORY;
}
-
/*
FUNCTION
- bfd_is_section_compressed
+ bfd_is_section_compressed_with_header
SYNOPSIS
- bfd_boolean bfd_is_section_compressed
- (bfd *abfd, asection *section);
+ bfd_boolean bfd_is_section_compressed_with_header
+ (bfd *abfd, asection *section,
+ int *compression_header_size_p);
DESCRIPTION
- Return @code{TRUE} if @var{section} is compressed.
+ Return @code{TRUE} if @var{section} is compressed. Compression
+ header size is returned in @var{compression_header_size_p}. If
+ compression is unsupported, compression header size is returned
+ with -1.
*/
bfd_boolean
-bfd_is_section_compressed (bfd *abfd, sec_ptr sec)
+bfd_is_section_compressed_with_header (bfd *abfd, sec_ptr sec,
+ int *compression_header_size_p)
{
- bfd_byte compressed_buffer [12];
+ bfd_byte header[MAX_COMPRESSION_HEADER_SIZE + 12];
+ int compression_header_size;
+ int header_size = 12;
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;
+
/* 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"));
+ compressed = bfd_get_section_contents (abfd, sec, header, 0,
+ header_size)
+ && CONST_STRNEQ ((char*) header + compression_header_size,
+ "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;
+ 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))
+ compression_header_size = -1;
+ }
+ /* 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. */
+ else if (strcmp (sec->name, ".debug_str") == 0
+ && ISPRINT (header[compression_header_size + 4]))
+ compressed = FALSE;
+ }
/* Restore compress_status. */
sec->compress_status = saved;
+ *compression_header_size_p = compression_header_size;
return compressed;
}
/*
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)
+{
+ int compression_header_size;
+ return (bfd_is_section_compressed_with_header (abfd, sec,
+ &compression_header_size)
+ && compression_header_size >= 0);
+}
+
+/*
+FUNCTION
bfd_init_section_decompress_status
SYNOPSIS
@@ -319,13 +451,20 @@ DESCRIPTION
bfd_boolean
bfd_init_section_decompress_status (bfd *abfd, sec_ptr sec)
{
- bfd_byte compressed_buffer [12];
+ bfd_byte header[MAX_COMPRESSION_HEADER_SIZE + 12];
+ int compression_header_size;
+ int header_size = 12;
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;
+
if (sec->rawsize != 0
|| sec->contents != NULL
|| sec->compress_status != COMPRESS_SECTION_NONE
- || !bfd_get_section_contents (abfd, sec, compressed_buffer, 0, 12))
+ || !bfd_get_section_contents (abfd, sec, header, 0, header_size))
{
bfd_set_error (bfd_error_invalid_operation);
return FALSE;
@@ -333,13 +472,20 @@ bfd_init_section_decompress_status (bfd *abfd, sec_ptr sec)
/* 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"))
+ if (! CONST_STRNEQ ((char*) header + compression_header_size, "ZLIB"))
{
bfd_set_error (bfd_error_wrong_format);
return FALSE;
}
- uncompressed_size = bfd_getb64 (compressed_buffer + 4);
+ uncompressed_size = bfd_getb64 (header + compression_header_size + 4);
+ if (compression_header_size != 0
+ && !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;
@@ -389,9 +535,12 @@ bfd_init_section_compress_status (bfd *abfd, sec_ptr sec)
0, uncompressed_size))
ret = FALSE;
else
- ret = bfd_compress_section_contents (abfd, sec,
- uncompressed_buffer,
- uncompressed_size);
+ {
+ uncompressed_size = bfd_compress_section_contents (abfd, sec,
+ uncompressed_buffer,
+ uncompressed_size);
+ ret = uncompressed_size != 0;
+ }
return ret;
}