text: # Copyright 2018 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.
  
  """
      Creates a SVG graph of the view hierarchy, when stopped in a
      method of an object that inherits from views::View. Requires
      graphviz.
  
      For more info see
      chromium/src/+/HEAD/docs/graphical_debugging_aid_chromium_views.md
  
      To make this command available, add the following to your ~/.lldbinit:
      command script import {Path to SRC Root}/tools/lldb/lldb_viewg.py
  
      Usage: type `viewg` at the LLDB prompt, given the conditions above.
  """
  
  import lldb
  import os
  
  def view_graph(debugger, command, result, internal_dict):
    dot = os.path.expanduser("~/state.dot")
    svg = os.path.splitext(dot)[0] + ".svg"
  
    process = debugger.GetSelectedTarget().GetProcess()
    frame = process.GetSelectedThread().GetSelectedFrame()
  
    cstr_address = frame.EvaluateExpression("views::PrintViewGraph(this).c_str()")
    if not cstr_address.GetError().Success():
      return
    str_size = frame.EvaluateExpression("(size_t)strlen(%s)"
                                        % cstr_address.GetValue())
    if not str_size.GetError().Success():
      return
    error = lldb.SBError()
    dot_str = process.ReadCStringFromMemory(int(cstr_address.GetValue(), 16),
                                            str_size.GetValueAsUnsigned(), error)
    if not error.Success():
      return
  
    with open(dot, "w") as f:
      f.write(dot_str)
      os.system("dot -Tsvg -o %s %s" % (svg, dot))
  
  def __lldb_init_module(debugger, internal_dict):
    debugger.HandleCommand('command script add -f lldb_viewg.view_graph viewg')
  