music with stepper motors
You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.

69 lines
2.2 KiB

5 years ago
#-------------------------------------------------------------------------------
# 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