[lldb-dev] Callback API question

[Malea, Daniel]

Hi Greg, or whoever reads this first,

I have a question about the python API lldb.SBBreakpoint.SetCallback function. According to the docs, the signature is:

SetCallback(self, *args) unbound lldb.SBBreakpoint method
    SetCallback(self, BreakpointHitCallback callback, void baton)

However, I am not sure how to create an instance of the BreakpointHitCallback type that is required for the second parameter. I'm not seeing any class in the Python API that is named that; only the C++ API has a typedef of that name:

typedef bool (*BreakpointHitCallback) (void *baton,
                                       SBProcess &process,
                                       SBThread &thread,
                                       lldb::SBBreakpointLocation &location);


I tried passing a function that has (what I believe is) the correct signature:

class MyTestCase(TestBase):
  def bp_callback(self, process, thread, breakpoint_loc):
    Pass

  def register_callback(self, target)
    breakpoint = target.BreakpointCreateByLocation('main.c', self.line1)
    breakpoint.SetCallback(self.bp_callback, self)


But I am getting a python error:

TypeError: in method 'SBBreakpoint_SetCallback', argument 2 of type 'lldb::SBBreakpoint::BreakpointHitCallback'

So, my question is: is it possible to register a callback to be called when a breakpoint is hit using that function? If so, what am I doing wrong? If not, is it preferable to create an SBListener for this purpose, or is the "target stop-hook add" command the only way to do what I'm trying to do? I'm trying to avoid using the built-in script interpreter..



Thanks,
Dan