java_deobfuscate.py: Update regexp to match thread dump stacks

build/android/stacktrace/java_deobfuscate.py

 #!/usr/bin/env python
 # Copyright 2016 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 """A tool to deobfuscate Java stack traces.
 
 Utility wrapper around ReTrace to deobfuscate stack traces that have been
 mangled by ProGuard. Takes stack traces from stdin (eg. adb logcat |
 java_deobfuscate.py proguard.mapping) and files.
 """
 
-# Can just run:
-# java -jar third_party/proguard/lib/retrace.jar -regex \
-# "(?:.*?\bat\s+%c\.%m\s*\(%s(?::%l)?\)\s*)|(?:(?:.*?[:\"]\s+)?%c(?::.*)?)" \
-# ~/mapping
-# in terminal to achieve same effect as this tool.
-
 import argparse
 import os
-import subprocess
-import sys
 
-_THIRD_PARTY_DIR = os.path.abspath(os.path.join(os.path.dirname(__file__),
-                                                os.pardir, os.pardir, os.pardir,
-                                                'third_party'))
-sys.path.append(os.path.join(_THIRD_PARTY_DIR, 'catapult', 'devil'))
-from devil.utils import cmd_helper
+_SRC_DIR = os.path.normpath(
+    os.path.join(os.path.dirname(__file__), os.pardir, os.pardir, os.pardir))
 
-
-# This regex is taken from
+# This regex is based on the one from:
 # http://proguard.sourceforge.net/manual/retrace/usage.html.
+# But with the "at" part changed to "(?::|\bat)", to account for lines like:

[mikecase (-- gone --), 2017/06/22 20:34:16]

Do you have an example of the type of lines this normally matches?

[agrieve, 2017/06/23 01:48:22]

Done.

+# 06-22 13:58:02.895  4674  4674 E THREAD_STATE:     bLA.a(PG:173)
 _LINE_PARSE_REGEX = (
-    r'(?:.*?\bat\s+%c\.%m\s*\(%s(?::%l)?\)\s*)|(?:(?:.*?[:"]\s+)?%c(?::.*)?)')
+    r'(?:.*?(?::|\bat)\s+%c\.%m\s*\(%s(?::%l)?\)\s*)|'
+    r'(?:(?:.*?[:"]\s+)?%c(?::.*)?)')
 
 
 def main():
   parser = argparse.ArgumentParser(description=(__doc__))
   parser.add_argument(
       'mapping_file',
       help='ProGuard mapping file from build which the stacktrace is from.')
   parser.add_argument(
       '--stacktrace',
       help='Stacktrace file to be deobfuscated.')
   args = parser.parse_args()
 
-  retrace_path = os.path.join(_THIRD_PARTY_DIR, 'proguard',
-                              'lib', 'retrace.jar')
+  retrace_path = os.path.join(
+      _SRC_DIR, 'third_party', 'proguard', 'lib', 'retrace.jar')
 
-  base_args = ['java', '-jar', retrace_path, '-regex', _LINE_PARSE_REGEX,
-               args.mapping_file]
+  cmd = ['java', '-jar', retrace_path, '-regex', _LINE_PARSE_REGEX,
+         args.mapping_file]
   if args.stacktrace:
-    subprocess.call(base_args + [args.stacktrace])
-  else:
-    for line in cmd_helper.IterCmdOutputLines(base_args):
-      print line
+    cmd.append(args.stacktrace)
+  os.execvp('java', cmd)
 
 
 if __name__ == '__main__':
   main()