GDB wrapper refactoring for memcheck_analyze.py

(This changelist is prepared by Alexander Potapenko, cc'ed)
This is a small refactoring that moves the GDB querying logic into a
separate module to allow us using it from tsan_analyze as well (we need it finally).

The diff is almost equal to http://codereview.chromium.org/175026,
I've only swapped two lines to make it applicable to the current trunk version.
Review URL: http://codereview.chromium.org/211023

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@26911 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 87 insertions, 0 deletions

diff --git a/tools/valgrind/gdb_helper.py b/tools/valgrind/gdb_helper.py
new file mode 100644
index 0000000..9b57c84
--- /dev/null
+++ b/tools/valgrind/gdb_helper.py
@@ -0,0 +1,87 @@
+#!/usr/bin/python
+# Copyright (c) 2006-2009 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.
+
+# gdb_helper.py
+
+''' A bunch of helper functions for querying gdb.'''
+
+import logging
+import os
+import re
+import tempfile
+
+GDB_LINE_RE = re.compile(r'Line ([0-9]*) of "([^"]*)".*')
+
+def _GdbOutputToFileLine(output_line):
+  ''' Parse the gdb output line, return a pair (file, line num) '''
+  match =  GDB_LINE_RE.match(output_line)
+  if match:
+    return match.groups()[1], match.groups()[0]
+  else:
+    return None
+
+def ResolveAddressesWithinABinary(binary_name, load_address, address_list):
+  ''' For each address, return a pair (file, line num) '''
+  commands = tempfile.NamedTemporaryFile()
+  commands.write('add-symbol-file "%s" %s\n' % (binary_name, load_address))
+  for addr in address_list:
+    commands.write('info line *%s\n' % addr)
+  commands.write('quit\n')
+  commands.flush()
+  gdb_commandline = 'gdb -batch -x %s 2>/dev/null' % commands.name
+  gdb_pipe = os.popen(gdb_commandline)
+  result = gdb_pipe.readlines()
+
+  address_count = 0
+  ret = {}
+  for line in result:
+    if line.startswith('Line'):
+      ret[address_list[address_count]] = _GdbOutputToFileLine(line)
+      address_count += 1
+    if line.startswith('No line'):
+      ret[address_list[address_count]] = (None, None)
+      address_count += 1
+  gdb_pipe.close()
+  commands.close()
+  return ret
+
+class AddressTable(object):
+  ''' Object to do batched line number lookup. '''
+  def __init__(self):
+    self._load_addresses = {}
+    self._binaries = {}
+    self._all_resolved = False
+
+  def AddBinaryAt(self, binary, load_address):
+    ''' Register a new shared library or executable. '''
+    self._load_addresses[binary] = load_address
+
+  def Add(self, binary, address):
+    ''' Register a lookup request. '''
+    if binary == '':
+      logging.warn('adding address %s in empty binary?' % address)
+    if binary in self._binaries:
+      self._binaries[binary].append(address)
+    else:
+      self._binaries[binary] = [address]
+    self._all_resolved = False
+
+  def ResolveAll(self):
+    ''' Carry out all lookup requests. '''
+    self._translation = {}
+    for binary in self._binaries.keys():
+      if binary != '' and binary in self._load_addresses:
+        load_address = self._load_addresses[binary]
+        addr = ResolveAddressesWithinABinary(binary, load_address, self._binaries[binary])
+        self._translation[binary] = addr
+    self._all_resolved = True
+
+  def GetFileLine(self, binary, addr):
+    ''' Get the (filename, linenum) result of a previously-registered lookup request. '''
+    if self._all_resolved:
+      if binary in self._translation:
+        if addr in self._translation[binary]:
+          return self._translation[binary][addr]
+    return (None, None)