/* DWARF 2 support.
- Copyright 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003,
- 2004, 2005, 2006, 2007, 2008, 2009, 2010 Free Software Foundation, Inc.
+ Copyright 1994-2013 Free Software Foundation, Inc.
Adapted from gdb/dwarf2read.c by Gavin Koch of Cygnus Solutions
(gavin@cygnus.com).
asection *sec;
bfd_byte *sec_info_ptr;
+ /* Support for alternate debug info sections created by the DWZ utility:
+ This includes a pointer to an alternate bfd which contains *extra*,
+ possibly duplicate debug sections, and pointers to the loaded
+ .debug_str and .debug_info sections from this bfd. */
+ bfd * alt_bfd_ptr;
+ bfd_byte * alt_dwarf_str_buffer;
+ bfd_size_type alt_dwarf_str_size;
+ bfd_byte * alt_dwarf_info_buffer;
+ bfd_size_type alt_dwarf_info_size;
+
/* A pointer to the memory block allocated for info_ptr. Neither
info_ptr nor sec_info_ptr are guaranteed to stay pointing to the
beginning of the malloc block. This is used only to free the
{ ".debug_aranges", ".zdebug_aranges" },
{ ".debug_frame", ".zdebug_frame" },
{ ".debug_info", ".zdebug_info" },
+ { ".debug_info", ".zdebug_info" },
{ ".debug_line", ".zdebug_line" },
{ ".debug_loc", ".zdebug_loc" },
{ ".debug_macinfo", ".zdebug_macinfo" },
{ ".debug_static_func", ".zdebug_static_func" },
{ ".debug_static_vars", ".zdebug_static_vars" },
{ ".debug_str", ".zdebug_str", },
+ { ".debug_str", ".zdebug_str", },
{ ".debug_types", ".zdebug_types" },
/* GNU DWARF 1 extensions */
{ ".debug_sfnames", ".zdebug_sfnames" },
{ NULL, NULL },
};
+/* NB/ Numbers in this enum must match up with indicies
+ into the dwarf_debug_sections[] array above. */
enum dwarf_debug_section_enum
{
debug_abbrev = 0,
debug_aranges,
debug_frame,
debug_info,
+ debug_info_alt,
debug_line,
debug_loc,
debug_macinfo,
debug_static_func,
debug_static_vars,
debug_str,
+ debug_str_alt,
debug_types,
debug_sfnames,
debug_srcinfo,
asection *msec;
const char *section_name = sec->uncompressed_name;
- /* read_section is a noop if the section has already been read. */
- if (!*section_buffer)
+ /* The section may have already been read. */
+ if (*section_buffer == NULL)
{
msec = bfd_get_section_by_name (abfd, section_name);
if (! msec)
return str;
}
+/* Like read_indirect_string but uses a .debug_str located in
+ an alternate filepointed to by the .gnu_debuglink section.
+ Used to impement DW_FORM_GNU_strp_alt. */
+
+static char *
+read_alt_indirect_string (struct comp_unit * unit,
+ bfd_byte * buf,
+ unsigned int * bytes_read_ptr)
+{
+ bfd_uint64_t offset;
+ struct dwarf2_debug *stash = unit->stash;
+ char *str;
+
+ if (unit->offset_size == 4)
+ offset = read_4_bytes (unit->abfd, buf);
+ else
+ offset = read_8_bytes (unit->abfd, buf);
+
+ *bytes_read_ptr = unit->offset_size;
+
+ if (stash->alt_bfd_ptr == NULL)
+ {
+ bfd * debug_bfd;
+ char * debug_filename = bfd_follow_gnu_debugaltlink (unit->abfd, DEBUGDIR);
+
+ if (debug_filename == NULL)
+ return NULL;
+
+ if ((debug_bfd = bfd_openr (debug_filename, NULL)) == NULL
+ || ! bfd_check_format (debug_bfd, bfd_object))
+ {
+ if (debug_bfd)
+ bfd_close (debug_bfd);
+
+ /* FIXME: Should we report our failure to follow the debuglink ? */
+ free (debug_filename);
+ return NULL;
+ }
+ stash->alt_bfd_ptr = debug_bfd;
+ }
+
+ if (! read_section (unit->stash->alt_bfd_ptr,
+ stash->debug_sections + debug_str_alt,
+ NULL, /* FIXME: Do we need to load alternate symbols ? */
+ offset,
+ &stash->alt_dwarf_str_buffer,
+ &stash->alt_dwarf_str_size))
+ return NULL;
+
+ str = (char *) stash->alt_dwarf_str_buffer + offset;
+ if (*str == '\0')
+ return NULL;
+
+ return str;
+}
+
+/* Resolve an alternate reference from UNIT at OFFSET.
+ Returns a pointer into the loaded alternate CU upon success
+ or NULL upon failure. */
+
+static bfd_byte *
+read_alt_indirect_ref (struct comp_unit * unit,
+ bfd_uint64_t offset)
+{
+ struct dwarf2_debug *stash = unit->stash;
+
+ if (stash->alt_bfd_ptr == NULL)
+ {
+ bfd * debug_bfd;
+ char * debug_filename = bfd_follow_gnu_debugaltlink (unit->abfd, DEBUGDIR);
+
+ if (debug_filename == NULL)
+ return FALSE;
+
+ if ((debug_bfd = bfd_openr (debug_filename, NULL)) == NULL
+ || ! bfd_check_format (debug_bfd, bfd_object))
+ {
+ if (debug_bfd)
+ bfd_close (debug_bfd);
+
+ /* FIXME: Should we report our failure to follow the debuglink ? */
+ free (debug_filename);
+ return NULL;
+ }
+ stash->alt_bfd_ptr = debug_bfd;
+ }
+
+ if (! read_section (unit->stash->alt_bfd_ptr,
+ stash->debug_sections + debug_info_alt,
+ NULL, /* FIXME: Do we need to load alternate symbols ? */
+ offset,
+ &stash->alt_dwarf_info_buffer,
+ &stash->alt_dwarf_info_size))
+ return NULL;
+
+ return stash->alt_dwarf_info_buffer + offset;
+}
+
static bfd_uint64_t
read_address (struct comp_unit *unit, bfd_byte *buf)
{
attr->u.val = read_address (unit, info_ptr);
info_ptr += unit->addr_size;
break;
+ case DW_FORM_GNU_ref_alt:
case DW_FORM_sec_offset:
if (unit->offset_size == 4)
attr->u.val = read_4_bytes (unit->abfd, info_ptr);
attr->u.str = read_indirect_string (unit, info_ptr, &bytes_read);
info_ptr += bytes_read;
break;
+ case DW_FORM_GNU_strp_alt:
+ attr->u.str = read_alt_indirect_string (unit, info_ptr, &bytes_read);
+ info_ptr += bytes_read;
+ break;
case DW_FORM_exprloc:
case DW_FORM_block:
amt = sizeof (struct dwarf_block);
info_ptr = read_attribute_value (attr, form, unit, info_ptr);
break;
default:
- (*_bfd_error_handler) (_("Dwarf Error: Invalid or unhandled FORM value: %u."),
+ (*_bfd_error_handler) (_("Dwarf Error: Invalid or unhandled FORM value: %#x."),
form);
bfd_set_error (bfd_error_bad_value);
return NULL;
struct abbrev_info *abbrev;
bfd_uint64_t die_ref = attr_ptr->u.val;
struct attribute attr;
- char *name = 0;
+ char *name = NULL;
/* DW_FORM_ref_addr can reference an entry in a different CU. It
is an offset from the .debug_info section, not the current CU. */
info_ptr = unit->sec_info_ptr + die_ref;
}
+ else if (attr_ptr->form == DW_FORM_GNU_ref_alt)
+ {
+ info_ptr = read_alt_indirect_ref (unit, die_ref);
+ if (info_ptr == NULL)
+ {
+ (*_bfd_error_handler)
+ (_("Dwarf Error: Unable to read alt ref %u."), die_ref);
+ bfd_set_error (bfd_error_bad_value);
+ return name;
+ }
+ }
else
info_ptr = unit->info_ptr_unit + die_ref;
+
abbrev_number = read_unsigned_leb128 (abfd, info_ptr, &bytes_read);
info_ptr += bytes_read;
free (stash->info_ptr_memory);
if (stash->close_on_cleanup)
bfd_close (stash->bfd_ptr);
+ if (stash->alt_dwarf_str_buffer)
+ free (stash->alt_dwarf_str_buffer);
+ if (stash->alt_dwarf_info_buffer)
+ free (stash->alt_dwarf_info_buffer);
+ if (stash->alt_bfd_ptr)
+ bfd_close (stash->alt_bfd_ptr);
}
This facilitates "optional" provision of debugging information, without
having to provide two complete copies of every binary object (with and
- without debug symbols).
-*/
+ without debug symbols). */
+
+#define GNU_DEBUGLINK ".gnu_debuglink"
+#define GNU_DEBUGALTLINK ".gnu_debugaltlink"
-#define GNU_DEBUGLINK ".gnu_debuglink"
/*
FUNCTION
bfd_calc_gnu_debuglink_crc32
return name;
}
+/*
+FUNCTION
+ bfd_get_alt_debug_link_info
+
+SYNOPSIS
+ char *bfd_get_alt_debug_link_info (bfd *abfd, unsigned long *crc32_out);
+
+DESCRIPTION
+ Fetch the filename and BuildID value for any alternate debuginfo
+ associated with @var{abfd}. Return NULL if no such info found,
+ otherwise return filename and update @var{buildid_out}. The
+ returned filename is allocated with @code{malloc}; freeing it
+ is the responsibility of the caller.
+*/
+
+char *
+bfd_get_alt_debug_link_info (bfd * abfd, unsigned long * buildid_out)
+{
+ asection *sect;
+ bfd_byte *contents;
+ int buildid_offset;
+ char *name;
+
+ BFD_ASSERT (abfd);
+ BFD_ASSERT (buildid_out);
+
+ sect = bfd_get_section_by_name (abfd, GNU_DEBUGALTLINK);
+
+ if (sect == NULL)
+ return NULL;
+
+ if (!bfd_malloc_and_get_section (abfd, sect, & contents))
+ {
+ if (contents != NULL)
+ free (contents);
+ return NULL;
+ }
+
+ /* BuildID value is stored after the filename, aligned up to 4 bytes. */
+ name = (char *) contents;
+ buildid_offset = strlen (name) + 1;
+ buildid_offset = (buildid_offset + 3) & ~3;
+
+ * buildid_out = bfd_get_32 (abfd, contents + buildid_offset);
+
+ return name;
+}
+
/*
INTERNAL_FUNCTION
separate_debug_file_exists
return crc == file_crc;
}
+/*
+INTERNAL_FUNCTION
+ separate_alt_debug_file_exists
+
+SYNOPSIS
+ bfd_boolean separate_alt_debug_file_exists
+ (char *name, unsigned long crc32);
+
+DESCRIPTION
+ Checks to see if @var{name} is a file and if its BuildID
+ matches @var{buildid}.
+*/
+
+static bfd_boolean
+separate_alt_debug_file_exists (const char *name,
+ const unsigned long buildid ATTRIBUTE_UNUSED)
+{
+ FILE *f;
+
+ BFD_ASSERT (name);
+
+ f = real_fopen (name, FOPEN_RB);
+ if (f == NULL)
+ return FALSE;
+
+ /* FIXME: Add code to check buildid. */
+
+ fclose (f);
+
+ return TRUE;
+}
/*
INTERNAL_FUNCTION
char *find_separate_debug_file (bfd *abfd);
DESCRIPTION
- Searches @var{abfd} for a reference to separate debugging
- information, scans various locations in the filesystem, including
- the file tree rooted at @var{debug_file_directory}, and returns a
- filename of such debugging information if the file is found and has
- matching CRC32. Returns NULL if no reference to debugging file
- exists, or file cannot be found.
+ Searches @var{abfd} for a section called @var{section_name} which
+ is expected to contain a reference to a file containing separate
+ debugging information. The function scans various locations in
+ the filesystem, including the file tree rooted at
+ @var{debug_file_directory}, and returns the first matching
+ filename that it finds. If @var{check_crc} is TRUE then the
+ contents of the file must also match the CRC value contained in
+ @var{section_name}. Returns NULL if no valid file could be found.
*/
+typedef char * (* get_func_type) (bfd *, unsigned long *);
+typedef bfd_boolean (* check_func_type) (const char *, const unsigned long);
+
static char *
-find_separate_debug_file (bfd *abfd, const char *debug_file_directory)
+find_separate_debug_file (bfd * abfd,
+ const char * debug_file_directory,
+ get_func_type get_func,
+ check_func_type check_func)
{
char *base;
char *dir;
return NULL;
}
- base = bfd_get_debug_link_info (abfd, & crc32);
+ base = get_func (abfd, & crc32);
+
if (base == NULL)
return NULL;
+ strlen (base)
+ 1);
if (debugfile == NULL)
- {
- free (base);
- free (dir);
- free (canon_dir);
- return NULL;
- }
+ goto found; /* Actually this returns NULL. */
/* First try in the same directory as the original file: */
strcpy (debugfile, dir);
strcat (debugfile, base);
- if (separate_debug_file_exists (debugfile, crc32))
- {
- free (base);
- free (dir);
- free (canon_dir);
- return debugfile;
- }
+ if (check_func (debugfile, crc32))
+ goto found;
/* Then try in a subdirectory called .debug. */
strcpy (debugfile, dir);
strcat (debugfile, ".debug/");
strcat (debugfile, base);
- if (separate_debug_file_exists (debugfile, crc32))
- {
- free (base);
- free (dir);
- free (canon_dir);
- return debugfile;
- }
+ if (check_func (debugfile, crc32))
+ goto found;
/* Then try in the global debugfile directory. */
strcpy (debugfile, debug_file_directory);
strcat (debugfile, canon_dir);
strcat (debugfile, base);
- if (separate_debug_file_exists (debugfile, crc32))
- {
- free (base);
- free (dir);
- free (canon_dir);
- return debugfile;
- }
+ if (check_func (debugfile, crc32))
+ goto found;
+ /* Failed to find the file. */
free (debugfile);
+ debugfile = NULL;
+
+ found:
free (base);
free (dir);
free (canon_dir);
- return NULL;
+ return debugfile;
}
char *
bfd_follow_gnu_debuglink (bfd *abfd, const char *dir)
{
- return find_separate_debug_file (abfd, dir);
+ return find_separate_debug_file (abfd, dir,
+ bfd_get_debug_link_info,
+ separate_debug_file_exists);
+}
+
+/*
+FUNCTION
+ bfd_follow_gnu_debugaltlink
+
+SYNOPSIS
+ char *bfd_follow_gnu_debugaltlink (bfd *abfd, const char *dir);
+
+DESCRIPTION
+
+ Takes a BFD and searches it for a .gnu_debugaltlink section. If this
+ section is found, it examines the section for the name of a file
+ containing auxiliary debugging information. It then searches the
+ filesystem for this file in a set of standard locations, including
+ the directory tree rooted at @var{dir}, and if found returns the
+ full filename.
+
+ If @var{dir} is NULL, it will search a default path configured into
+ libbfd at build time. [FIXME: This feature is not currently
+ implemented].
+
+RETURNS
+ <<NULL>> on any errors or failure to locate the debug file,
+ otherwise a pointer to a heap-allocated string containing the
+ filename. The caller is responsible for freeing this string.
+*/
+
+char *
+bfd_follow_gnu_debugaltlink (bfd *abfd, const char *dir)
+{
+ return find_separate_debug_file (abfd, dir,
+ bfd_get_alt_debug_link_info,
+ separate_alt_debug_file_exists);
}
/*
projects / binutils-gdb.git / commitdiff