from .lineprogram import LineProgram
from .callframe import CallFrameInfo
from .locationlists import LocationLists
+from .ranges import RangeLists
# Describes a debug section
debug_frame_sec,
debug_str_sec,
debug_loc_sec,
+ debug_ranges_sec,
debug_line_sec):
""" config:
A DwarfConfig object
self.debug_frame_sec = debug_frame_sec
self.debug_str_sec = debug_str_sec
self.debug_loc_sec = debug_loc_sec
+ self.debug_ranges_sec = debug_ranges_sec
self.debug_line_sec = debug_line_sec
# This is the DWARFStructs the context uses, so it doesn't depend on
"""
return LocationLists(self.debug_loc_sec.stream, self.structs)
+ def range_lists(self):
+ """ Get a RangeLists object representing the .debug_ranges section of
+ the DWARF data, or None if this section doesn't exist.
+ """
+ return RangeLists(self.debug_ranges_sec.stream, self.structs)
+
#------ PRIVATE ------#
def _parse_CUs_iter(self):
#-------------------------------------------------------------------------------
# elftools: dwarf/locationlists.py
#
-# DWARF location lists section decoding
+# DWARF location lists section decoding (.debug_loc)
#
# Eli Bendersky (eliben@gmail.com)
# This code is in the public domain
--- /dev/null
+#-------------------------------------------------------------------------------
+# elftools: dwarf/ranges.py
+#
+# DWARF ranges section decoding (.debug_ranges)
+#
+# Eli Bendersky (eliben@gmail.com)
+# This code is in the public domain
+#-------------------------------------------------------------------------------
+import os
+from collections import namedtuple
+
+from ..common.utils import struct_parse
+
+
+RangeEntry = namedtuple('RangeEntry', 'begin_offset end_offset')
+BaseAddressEntry = namedtuple('BaseAddressEntry', 'base_address')
+
+
+class RangeLists(object):
+ """ A single range list is a Python list consisting of RangeEntry or
+ BaseAddressEntry objects.
+ """
+ def __init__(self, stream, structs):
+ self.stream = stream
+ self.structs = structs
+ self._max_addr = 2 ** (self.structs.address_size * 8) - 1
+
+ def get_range_list_at_offset(self, offset):
+ """ Get a range list at the given offset in the section.
+ """
+ self.stream.seek(offset, os.SEEK_SET)
+ return self._parse_range_list_from_stream()
+
+ def iter_range_lists(self):
+ """ Yield all range lists found in the section.
+ """
+ # Just call _parse_range_list_from_stream until the stream ends
+ self.stream.seek(0, os.SEEK_END)
+ endpos = self.stream.tell()
+
+ self.stream.seek(0, os.SEEK_SET)
+ while self.stream.tell() < endpos:
+ yield self._parse_range_list_from_stream()
+
+ #------ PRIVATE ------#
+
+ def _parse_range_list_from_stream(self):
+ lst = []
+ while True:
+ begin_offset = struct_parse(
+ self.structs.Dwarf_target_addr(''), self.stream)
+ end_offset = struct_parse(
+ self.structs.Dwarf_target_addr(''), self.stream)
+ if begin_offset == 0 and end_offset == 0:
+ # End of list - we're done.
+ break
+ elif begin_offset == self._max_addr:
+ # Base address selection entry
+ lst.append(BaseAddressEntry(base_address=end_offset))
+ else:
+ # Range entry
+ lst.append(RangeEntry(
+ begin_offset=begin_offset,
+ end_offset=end_offset))
+ return lst
+
+
+
#
debug_sections = {}
for secname in ('.debug_info', '.debug_abbrev', '.debug_str',
- '.debug_line', '.debug_frame', '.debug_loc'):
+ '.debug_line', '.debug_frame', '.debug_loc',
+ '.debug_ranges'):
section = self.get_section_by_name(secname)
if section is None:
debug_sections[secname] = None
debug_frame_sec=debug_sections['.debug_frame'],
debug_str_sec=debug_sections['.debug_str'],
debug_loc_sec=debug_sections['.debug_loc'],
+ debug_ranges_sec=debug_sections['.debug_ranges'],
debug_line_sec=debug_sections['.debug_line'])
def get_machine_arch(self):
--- /dev/null
+#-------------------------------------------------------------------------------
+# elftools example: dwarf_range_lists.py
+#
+# Examine DIE entries which have range list values, and decode these range
+# lists.
+#
+# Eli Bendersky (eliben@gmail.com)
+# This code is in the public domain
+#-------------------------------------------------------------------------------
+from __future__ import print_function
+import sys
+
+# If elftools is not installed, maybe we're running from the root or examples
+# dir of the source distribution
+try:
+ import elftools
+except ImportError:
+ sys.path.extend(['.', '..'])
+
+from elftools.elf.elffile import ELFFile
+from elftools.dwarf.descriptions import (
+ describe_DWARF_expr, set_global_machine_arch)
+from elftools.dwarf.ranges import RangeEntry
+
+
+def process_file(filename):
+ print('Processing file:', filename)
+ with open(filename) as f:
+ elffile = ELFFile(f)
+
+ if not elffile.has_dwarf_info():
+ print(' file has no DWARF info')
+ return
+
+ # get_dwarf_info returns a DWARFInfo context object, which is the
+ # starting point for all DWARF-based processing in pyelftools.
+ dwarfinfo = elffile.get_dwarf_info()
+
+ # The range lists are extracted by DWARFInfo from the .debug_ranges
+ # section, and returned here as a RangeLists object.
+ range_lists = dwarfinfo.range_lists()
+
+ for CU in dwarfinfo.iter_CUs():
+ # DWARFInfo allows to iterate over the compile units contained in
+ # the .debug_info section. CU is a CompileUnit object, with some
+ # computed attributes (such as its offset in the section) and
+ # a header which conforms to the DWARF standard. The access to
+ # header elements is, as usual, via item-lookup.
+ print(' Found a compile unit at offset %s, length %s' % (
+ CU.cu_offset, CU['unit_length']))
+
+ # A CU provides a simple API to iterate over all the DIEs in it.
+ for DIE in CU.iter_DIEs():
+ # Go over all attributes of the DIE. Each attribute is an
+ # AttributeValue object (from elftools.dwarf.die), which we
+ # can examine.
+ for attr in DIE.attributes.itervalues():
+ if attribute_has_range_list(attr):
+ # This is a range list. Its value is an offset into
+ # the .debug_ranges section, so we can use the range
+ # lists object to decode it.
+ rangelist = range_lists.get_range_list_at_offset(
+ attr.value)
+
+ print(' DIE %s. attr %s.\n%s' % (
+ DIE.tag,
+ attr.name,
+ rangelist))
+
+
+def attribute_has_range_list(attr):
+ """ Only some attributes can have range list values, if they have the
+ required DW_FORM (rangelistptr "class" in DWARF spec v3)
+ """
+ if attr.name == 'DW_AT_ranges':
+ if attr.form in ('DW_FORM_data4', 'DW_FORM_data8'):
+ return True
+ return False
+
+
+if __name__ == '__main__':
+ for filename in sys.argv[1:]:
+ process_file(filename)
+
+
+
+
+
+
+
projects / pyelftools.git / commitdiff