The Tor Browser / file revision

 #!/usr/bin/python

 # vim:sw=4:ts=4:et:

 # This Source Code Form is subject to the terms of the Mozilla Public

 # License, v. 2.0. If a copy of the MPL was not distributed with this

 # file, You can obtain one at http://mozilla.org/MPL/2.0/.

 # This script uses atos to process the output of nsTraceRefcnt's Mac OS

 # X stack walking code.  This is useful for two things:

 #  (1) Getting line number information out of

 #      |nsTraceRefcnt::WalkTheStack|'s output in debug builds.

 #  (2) Getting function names out of |nsTraceRefcnt::WalkTheStack|'s

 #      output on all builds (where it mostly prints UNKNOWN because only

 #      a handful of symbols are exported from component libraries).

 #

 # Use the script by piping output containing stacks (such as raw stacks

 # or make-tree.pl balance trees) through this script.

 import subprocess

 import sys

 import re

 import os

 import pty

 import termios

 class unbufferedLineConverter:

     """

     Wrap a child process that responds to each line of input with one line of

     output.  Uses pty to trick the child into providing unbuffered output.

     """

     def __init__(self, command, args = []):

         pid, fd = pty.fork()

         if pid == 0:

             # We're the child.  Transfer control to command.

             os.execvp(command, [command] + args)

         else:

             # Disable echoing.

             attr = termios.tcgetattr(fd)

             attr[3] = attr[3] & ~termios.ECHO

             termios.tcsetattr(fd, termios.TCSANOW, attr)

             # Set up a file()-like interface to the child process

             self.r = os.fdopen(fd, "r", 1)

             self.w = os.fdopen(os.dup(fd), "w", 1)

     def convert(self, line):

         self.w.write(line + "\n")

         return self.r.readline().rstrip("\r\n")

     @staticmethod

     def test():

         assert unbufferedLineConverter("rev").convert("123") == "321"

         assert unbufferedLineConverter("cut", ["-c3"]).convert("abcde") == "c"

         print "Pass"

 def separate_debug_file_for(file):

     return None

 address_adjustments = {}

 def address_adjustment(file):

     if not file in address_adjustments:

         result = None

         otool = subprocess.Popen(["otool", "-l", file], stdout=subprocess.PIPE)

         while True:

             line = otool.stdout.readline()

             if line == "":

                 break

             if line == "  segname __TEXT\n":

                 line = otool.stdout.readline()

                 if not line.startswith("   vmaddr "):

                     raise StandardError("unexpected otool output")

                 result = int(line[10:], 16)

                 break

         otool.stdout.close()

         if result is None:

             raise StandardError("unexpected otool output")

         address_adjustments[file] = result

     return address_adjustments[file]

 atoses = {}

 def addressToSymbol(file, address):

     converter = None

     if not file in atoses:

         debug_file = separate_debug_file_for(file) or file

         converter = unbufferedLineConverter('/usr/bin/xcrun', ['atos', '-arch', 'x86_64', '-o', debug_file])

         atoses[file] = converter

     else:

         converter = atoses[file]

     return converter.convert("0x%X" % address)

 cxxfilt_proc = None

 def cxxfilt(sym):

     if cxxfilt_proc is None:

         # --no-strip-underscores because atos already stripped the underscore

         globals()["cxxfilt_proc"] = subprocess.Popen(['c++filt',

                                                       '--no-strip-underscores',

                                                       '--format', 'gnu-v3'],

                                                      stdin=subprocess.PIPE,

                                                      stdout=subprocess.PIPE)

     cxxfilt_proc.stdin.write(sym + "\n")

     return cxxfilt_proc.stdout.readline().rstrip("\n")

 line_re = re.compile("^(.*) ?\[([^ ]*) \+(0x[0-9a-fA-F]{1,8})\](.*)$")

 balance_tree_re = re.compile("^([ \|0-9-]*)")

 atos_name_re = re.compile("^(.+) \(in ([^)]+)\) \((.+)\)$")

 def fixSymbols(line):

     result = line_re.match(line)

     if result is not None:

         # before allows preservation of balance trees

         # after allows preservation of counts

         (before, file, address, after) = result.groups()

         address = int(address, 16)

         if os.path.exists(file) and os.path.isfile(file):

             address += address_adjustment(file)

             info = addressToSymbol(file, address)

             # atos output seems to have three forms:

             #   address

             #   address (in foo.dylib)

             #   symbol (in foo.dylib) (file:line)

             name_result = atos_name_re.match(info)

             if name_result is not None:

                 # Print the first two forms as-is, and transform the third

                 (name, library, fileline) = name_result.groups()

                 # atos demangles, but occasionally it fails.  cxxfilt can mop

                 # up the remaining cases(!), which will begin with '_Z'.

                 if (name.startswith("_Z")):

                     name = cxxfilt(name)

                 info = "%s (%s, in %s)" % (name, fileline, library)

             # throw away the bad symbol, but keep balance tree structure

             before = balance_tree_re.match(before).groups()[0]

             return before + info + after + "\n"

         else:

             sys.stderr.write("Warning: File \"" + file + "\" does not exist.\n")

             return line

     else:

         return line

 if __name__ == "__main__":

     for line in sys.stdin:

         sys.stdout.write(fixSymbols(line))