def _add_subtree(self, parent_id, br):
def get_values(sr):
if hasattr(sr.data, 'name'):
desc = sr.data.name
else:
desc = str(sr.data)
(start, stop) = sr.abs_range()
return desc, format(start, ','), format(stop, ',')
pi = ProgressIndicator('show byte ranges...', 1)
for idx in xrange(len(br.subranges)):
subrange = br.subranges[idx]
child_id = parent_id + '.%d' % idx
if not self.byte_range_tree.tree.exists(child_id):
child_id = self.byte_range_tree.add(
parent_id, idx, values=get_values(subrange))
if len(subrange.subranges) > 0:
# if there are subsubranges, just insert 1st row so that the open icon is shown
if not self.byte_range_tree.tree.exists(child_id + '.0'):
subsubrange = subrange.subranges[0]
self.byte_range_tree.add(child_id,
0,
values=get_values(subsubrange))
pi.click()
pi.done()
def _add_subtree(self, parent_id, br):
def get_values(sr):
if hasattr(sr.data, 'name'):
desc = sr.data.name
else:
desc = str(sr.data)
(start, stop) = sr.abs_range()
return desc, format(start, ','), format(stop, ',')
pi = ProgressIndicator('show byte ranges...', 1)
for idx in xrange(len(br.subranges)):
subrange = br.subranges[idx]
child_id = parent_id + '.%d' % idx
if not self.byte_range_tree.tree.exists(child_id):
child_id = self.byte_range_tree.add(parent_id, idx, values=get_values(subrange))
if len(subrange.subranges) > 0:
# if there are subsubranges, just insert 1st row so that the open icon is shown
if not self.byte_range_tree.tree.exists(child_id + '.0'):
subsubrange = subrange.subranges[0]
self.byte_range_tree.add(child_id, 0, values=get_values(subsubrange))
pi.click()
pi.done()
def parse(self, symtab_command):
if symtab_command is None:
return
self.initialize(0, len(self.byte_range))
if ProgressIndicator.ENABLED:
progress = ProgressIndicator('parsing symbol table...', 4096)
else:
progress = None
# Add nlist entries and string table section.
sym_tab = SymbolTable(symtab_command.nsyms)
sym_str_tab = SymbolStringTable()
sym_br = self.add_section(symtab_command.symoff,
symtab_command.nsyms * self.nlist_size,
data=sym_tab)
self.add_section(symtab_command.stroff,
symtab_command.strsize,
data=sym_str_tab)
str_bytes_ = self.byte_range.bytes(
symtab_command.stroff,
symtab_command.stroff + symtab_command.strsize)
# Parse all nlist entries
for idx in xrange(symtab_command.nsyms):
if progress is not None:
progress.click()
start = idx * self.nlist_size
stop = start + self.nlist_size
bytes_ = sym_br.bytes(start, stop)
nlist = self.nlist_class(bytes_)
# The original code was:
#
# sym_br.add_subrange(start, self.nlist_size, data=nlist)
#
# The problem is that for a real iOS app, there can be hundreds of thousands if not
# millions of symbols and these Nlist and BytesRange objects consume a lot of memory.
# (Each python object with attribute seems to consume at least 300B.)
#
# The solution is to deviate the framework and save the values of these nlist headers
# into a big list.
sym_tab.add(nlist)
if nlist.n_strx == 0:
# From nlist.h:
#
# Symbols with a index into the string table of zero (n_un.n_strx == 0) are
# defined to have a null, "", name. Therefore all string indexes to non null
# names must not have a zero string index. This is bit historical information
# that has never been well documented.
pass
else:
(sym_name,
total_len) = self._find_string(str_bytes_, nlist.n_strx)
# Original code is:
#
# str_br.add_subrange(nlist.n_strx, total_len, data=SymtabString(nlist.n_strx, sym_name))
#
# Again, we avoid creating the byte range in order to reduce memory consumption.
sym_str_tab.add(nlist.n_strx, sym_name)
sym_tab.correlate_string_table(sym_str_tab)
if progress is not None:
progress.done()
