mirror of
https://sourceware.org/git/binutils-gdb.git
synced 2024-11-28 04:25:10 +08:00
291 lines
8.0 KiB
C
291 lines
8.0 KiB
C
/* Read MiniDebugInfo data from an objfile.
|
|
|
|
Copyright (C) 2012-2016 Free Software Foundation, Inc.
|
|
|
|
This file is part of GDB.
|
|
|
|
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, see <http://www.gnu.org/licenses/>. */
|
|
|
|
#include "defs.h"
|
|
#include "gdb_bfd.h"
|
|
#include "symfile.h"
|
|
#include "objfiles.h"
|
|
#include "gdbcore.h"
|
|
|
|
#ifdef HAVE_LIBLZMA
|
|
|
|
#include <lzma.h>
|
|
|
|
/* Allocator function for LZMA. */
|
|
|
|
static void *
|
|
alloc_lzma (void *opaque, size_t nmemb, size_t size)
|
|
{
|
|
return xmalloc (nmemb * size);
|
|
}
|
|
|
|
/* Free function for LZMA. */
|
|
|
|
static void
|
|
free_lzma (void *opaque, void *ptr)
|
|
{
|
|
xfree (ptr);
|
|
}
|
|
|
|
/* The allocator object for LZMA. Note that 'gdb_lzma_allocator'
|
|
cannot be const due to the lzma library function prototypes. */
|
|
|
|
static lzma_allocator gdb_lzma_allocator = { alloc_lzma, free_lzma, NULL };
|
|
|
|
/* Custom bfd_openr_iovec implementation to read compressed data from
|
|
a section. This keeps only the last decompressed block in memory
|
|
to allow larger data without using to much memory. */
|
|
|
|
struct gdb_lzma_stream
|
|
{
|
|
/* Section of input BFD from which we are decoding data. */
|
|
asection *section;
|
|
|
|
/* lzma library decompression state. */
|
|
lzma_index *index;
|
|
|
|
/* Currently decoded block. */
|
|
bfd_size_type data_start;
|
|
bfd_size_type data_end;
|
|
gdb_byte *data;
|
|
};
|
|
|
|
/* bfd_openr_iovec OPEN_P implementation for
|
|
find_separate_debug_file_in_section. OPEN_CLOSURE is 'asection *'
|
|
of the section to decompress.
|
|
|
|
Return 'struct gdb_lzma_stream *' must be freed by caller by xfree,
|
|
together with its INDEX lzma data. */
|
|
|
|
static void *
|
|
lzma_open (struct bfd *nbfd, void *open_closure)
|
|
{
|
|
asection *section = (asection *) open_closure;
|
|
bfd_size_type size, offset;
|
|
lzma_stream_flags options;
|
|
gdb_byte footer[LZMA_STREAM_HEADER_SIZE];
|
|
gdb_byte *indexdata;
|
|
lzma_index *index;
|
|
int ret;
|
|
uint64_t memlimit = UINT64_MAX;
|
|
struct gdb_lzma_stream *lstream;
|
|
size_t pos;
|
|
|
|
size = bfd_get_section_size (section);
|
|
offset = section->filepos + size - LZMA_STREAM_HEADER_SIZE;
|
|
if (size < LZMA_STREAM_HEADER_SIZE
|
|
|| bfd_seek (section->owner, offset, SEEK_SET) != 0
|
|
|| bfd_bread (footer, LZMA_STREAM_HEADER_SIZE, section->owner)
|
|
!= LZMA_STREAM_HEADER_SIZE
|
|
|| lzma_stream_footer_decode (&options, footer) != LZMA_OK
|
|
|| offset < options.backward_size)
|
|
{
|
|
bfd_set_error (bfd_error_wrong_format);
|
|
return NULL;
|
|
}
|
|
|
|
offset -= options.backward_size;
|
|
indexdata = (gdb_byte *) xmalloc (options.backward_size);
|
|
index = NULL;
|
|
pos = 0;
|
|
if (bfd_seek (section->owner, offset, SEEK_SET) != 0
|
|
|| bfd_bread (indexdata, options.backward_size, section->owner)
|
|
!= options.backward_size
|
|
|| lzma_index_buffer_decode (&index, &memlimit, &gdb_lzma_allocator,
|
|
indexdata, &pos, options.backward_size)
|
|
!= LZMA_OK
|
|
|| lzma_index_size (index) != options.backward_size)
|
|
{
|
|
xfree (indexdata);
|
|
bfd_set_error (bfd_error_wrong_format);
|
|
return NULL;
|
|
}
|
|
xfree (indexdata);
|
|
|
|
lstream = XCNEW (struct gdb_lzma_stream);
|
|
lstream->section = section;
|
|
lstream->index = index;
|
|
|
|
return lstream;
|
|
}
|
|
|
|
/* bfd_openr_iovec PREAD_P implementation for
|
|
find_separate_debug_file_in_section. Passed STREAM
|
|
is 'struct gdb_lzma_stream *'. */
|
|
|
|
static file_ptr
|
|
lzma_pread (struct bfd *nbfd, void *stream, void *buf, file_ptr nbytes,
|
|
file_ptr offset)
|
|
{
|
|
struct gdb_lzma_stream *lstream = (struct gdb_lzma_stream *) stream;
|
|
bfd_size_type chunk_size;
|
|
lzma_index_iter iter;
|
|
gdb_byte *compressed, *uncompressed;
|
|
file_ptr block_offset;
|
|
lzma_filter filters[LZMA_FILTERS_MAX + 1];
|
|
lzma_block block;
|
|
size_t compressed_pos, uncompressed_pos;
|
|
file_ptr res;
|
|
|
|
res = 0;
|
|
while (nbytes > 0)
|
|
{
|
|
if (lstream->data == NULL
|
|
|| lstream->data_start > offset || offset >= lstream->data_end)
|
|
{
|
|
asection *section = lstream->section;
|
|
|
|
lzma_index_iter_init (&iter, lstream->index);
|
|
if (lzma_index_iter_locate (&iter, offset))
|
|
break;
|
|
|
|
compressed = (gdb_byte *) xmalloc (iter.block.total_size);
|
|
block_offset = section->filepos + iter.block.compressed_file_offset;
|
|
if (bfd_seek (section->owner, block_offset, SEEK_SET) != 0
|
|
|| bfd_bread (compressed, iter.block.total_size, section->owner)
|
|
!= iter.block.total_size)
|
|
{
|
|
xfree (compressed);
|
|
break;
|
|
}
|
|
|
|
uncompressed = (gdb_byte *) xmalloc (iter.block.uncompressed_size);
|
|
|
|
memset (&block, 0, sizeof (block));
|
|
block.filters = filters;
|
|
block.header_size = lzma_block_header_size_decode (compressed[0]);
|
|
if (lzma_block_header_decode (&block, &gdb_lzma_allocator, compressed)
|
|
!= LZMA_OK)
|
|
{
|
|
xfree (compressed);
|
|
xfree (uncompressed);
|
|
break;
|
|
}
|
|
|
|
compressed_pos = block.header_size;
|
|
uncompressed_pos = 0;
|
|
if (lzma_block_buffer_decode (&block, &gdb_lzma_allocator,
|
|
compressed, &compressed_pos,
|
|
iter.block.total_size,
|
|
uncompressed, &uncompressed_pos,
|
|
iter.block.uncompressed_size)
|
|
!= LZMA_OK)
|
|
{
|
|
xfree (compressed);
|
|
xfree (uncompressed);
|
|
break;
|
|
}
|
|
|
|
xfree (compressed);
|
|
|
|
xfree (lstream->data);
|
|
lstream->data = uncompressed;
|
|
lstream->data_start = iter.block.uncompressed_file_offset;
|
|
lstream->data_end = (iter.block.uncompressed_file_offset
|
|
+ iter.block.uncompressed_size);
|
|
}
|
|
|
|
chunk_size = min (nbytes, lstream->data_end - offset);
|
|
memcpy (buf, lstream->data + offset - lstream->data_start, chunk_size);
|
|
buf = (gdb_byte *) buf + chunk_size;
|
|
offset += chunk_size;
|
|
nbytes -= chunk_size;
|
|
res += chunk_size;
|
|
}
|
|
|
|
return res;
|
|
}
|
|
|
|
/* bfd_openr_iovec CLOSE_P implementation for
|
|
find_separate_debug_file_in_section. Passed STREAM
|
|
is 'struct gdb_lzma_stream *'. */
|
|
|
|
static int
|
|
lzma_close (struct bfd *nbfd,
|
|
void *stream)
|
|
{
|
|
struct gdb_lzma_stream *lstream = (struct gdb_lzma_stream *) stream;
|
|
|
|
lzma_index_end (lstream->index, &gdb_lzma_allocator);
|
|
xfree (lstream->data);
|
|
xfree (lstream);
|
|
|
|
/* Zero means success. */
|
|
return 0;
|
|
}
|
|
|
|
/* bfd_openr_iovec STAT_P implementation for
|
|
find_separate_debug_file_in_section. Passed STREAM
|
|
is 'struct gdb_lzma_stream *'. */
|
|
|
|
static int
|
|
lzma_stat (struct bfd *abfd,
|
|
void *stream,
|
|
struct stat *sb)
|
|
{
|
|
struct gdb_lzma_stream *lstream = (struct gdb_lzma_stream *) stream;
|
|
|
|
memset (sb, 0, sizeof (struct stat));
|
|
sb->st_size = lzma_index_uncompressed_size (lstream->index);
|
|
return 0;
|
|
}
|
|
|
|
#endif /* HAVE_LIBLZMA */
|
|
|
|
/* This looks for a xz compressed separate debug info object file embedded
|
|
in a section called .gnu_debugdata. See
|
|
http://fedoraproject.org/wiki/Features/MiniDebugInfo
|
|
or the "Separate Debug Sections" of the manual for details.
|
|
If we find one we create a iovec based bfd that decompresses the
|
|
object data on demand. If we don't find one, return NULL. */
|
|
|
|
bfd *
|
|
find_separate_debug_file_in_section (struct objfile *objfile)
|
|
{
|
|
asection *section;
|
|
bfd *abfd;
|
|
|
|
if (objfile->obfd == NULL)
|
|
return NULL;
|
|
|
|
section = bfd_get_section_by_name (objfile->obfd, ".gnu_debugdata");
|
|
if (section == NULL)
|
|
return NULL;
|
|
|
|
#ifdef HAVE_LIBLZMA
|
|
abfd = gdb_bfd_openr_iovec (objfile_name (objfile), gnutarget, lzma_open,
|
|
section, lzma_pread, lzma_close, lzma_stat);
|
|
if (abfd == NULL)
|
|
return NULL;
|
|
|
|
if (!bfd_check_format (abfd, bfd_object))
|
|
{
|
|
warning (_("Cannot parse .gnu_debugdata section; not a BFD object"));
|
|
gdb_bfd_unref (abfd);
|
|
return NULL;
|
|
}
|
|
#else
|
|
warning (_("Cannot parse .gnu_debugdata section; LZMA support was "
|
|
"disabled at compile time"));
|
|
abfd = NULL;
|
|
#endif /* !HAVE_LIBLZMA */
|
|
|
|
return abfd;
|
|
}
|