build/android/symbolize.py

   1 #!/usr/bin/env python
   2 #
   3 # Copyright 2013 The Chromium Authors. All rights reserved.
   4 # Use of this source code is governed by a BSD-style license that can be
   5 # found in the LICENSE file.
   6
   7 """Symbolizes stack traces generated by Chromium for Android.
   8
   9 Sample usage:
  10   adb logcat chromium:V | symbolize.py
  11 """
  12
  13 import os
  14 import re
  15 import sys
  16
  17 from pylib import constants
  18
  19 # Uses symbol.py from third_party/android_platform, not python's.
  20 sys.path.insert(0,
  21                 os.path.join(constants.DIR_SOURCE_ROOT,
  22                             'third_party/android_platform/development/scripts'))
  23 import symbol
  24
  25 # Sample output from base/debug/stack_trace_android.cc
  26 #00 0x693cd34f /path/to/some/libfoo.so+0x0007434f
  27 TRACE_LINE = re.compile(r'(?P<frame>\#[0-9]+ 0x[0-9a-f]{8,8}) '
  28                         r'(?P<lib>[^+]+)\+0x(?P<addr>[0-9a-f]{8,8})')
  29
  30 class Symbolizer(object):
  31   def __init__(self, output):
  32     self._output = output
  33
  34   def write(self, data):
  35     while True:
  36       match = re.search(TRACE_LINE, data)
  37       if not match:
  38         self._output.write(data)
  39         break
  40
  41       frame = match.group('frame')
  42       lib = match.group('lib')
  43       addr = match.group('addr')
  44
  45       # TODO(scherkus): Doing a single lookup per line is pretty slow,
  46       # especially with larger libraries. Consider caching strategies such as:
  47       # 1) Have Python load the libraries and do symbol lookups instead of
  48       #    calling out to addr2line each time.
  49       # 2) Have Python keep multiple addr2line instances open as subprocesses,
  50       #    piping addresses and reading back symbols as we find them
  51       # 3) Read ahead the entire stack trace until we find no more, then batch
  52       #    the symbol lookups.
  53       #
  54       # TODO(scherkus): These results are memoized, which could result in
  55       # incorrect lookups when running this script on long-lived instances
  56       # (e.g., adb logcat) when doing incremental development. Consider clearing
  57       # the cache when modification timestamp of libraries change.
  58       # pylint: disable=no-member
  59       sym = symbol.SymbolInformation(lib, addr, False)[0][0]
  60
  61       if not sym:
  62         post = match.end('addr')
  63         self._output.write(data[:post])
  64         data = data[post:]
  65         continue
  66
  67       pre = match.start('frame')
  68       post = match.end('addr')
  69
  70       self._output.write(data[:pre])
  71       self._output.write(frame)
  72       self._output.write(' ')
  73       self._output.write(sym)
  74
  75       data = data[post:]
  76
  77   def flush(self):
  78     self._output.flush()
  79
  80
  81 def main():
  82   symbolizer = Symbolizer(sys.stdout)
  83   for line in sys.stdin:
  84     symbolizer.write(line)
  85   symbolizer.flush()
  86
  87
  88 if __name__ == '__main__':
  89   main()