Stefan Hajnoczi writes:
[...]
>> Maybe this would work nice for everybody:
>>
>> tracetool.py # main program (just parse cmdline opts and
>> call tracetool module)
>> tracetool/__init__.py # common boilerplate code (e.g., event parsing
>> and call dispatching)
>> tracetool/format/__init__.py # format auto-registration/lookup code
>> tracetool/format/h.py # code for the 'h' format
>> # __doc__ [mandatory, format
>> description]
>> # def begin(events) [optional]
>> # def end(events) [optional]
>> tracetool/backend/__init__.py # backend auto-registration/lookup code
>> tracetool/backend/simple.py # code for the 'simple' backend
>> # __doc__ [mandatory, backend
>> description]
>> # PUBLIC = [True|False] [optional,
>> # defaults to False,
>> # indicates it's listed
>> on --list-backends]
>> # def format(events) [optional,
>> # backend-specific code for
>> given format,
>> # implicitly indicates
>> format compatibility]
> Let's call this function backend.generate(events) instead of "format"
> since we already use that term and it's a Python builtin too. This is
> a code generation function.
Maybe I wasn't clear. I meant that for tracetool/backend/simple.py to work with
the format 'h', it must have the following routine:
def h (events):
...
That is, there must exist a routine with the same name of the format (with '-'
replaced with '_', when necessary) for the backend to be compatible with that
format.
>> Note that new formats will need to add new format routines in
>> 'tracetool/backend/nop.py' to accomodate whatever action has to be taken on
>> disabled events.
> I think it's more convenient to drop the nop backend and introduce a
> nop() code generation function for each format.
> The .h format would nop() function would emit a static inline empty C
> function that does nothing.
> The other formats could probably do nothing in nop().
Sounds good:
tracetool/format/f.py:
def begin (events):
...
def nop (events):
...
def end (events):
...
tracetool/__init__.py:
def generate (events, format, backend, force_nop = False):
if force_nop:
events = [ e.properties.add("disabled") for e in events ]
tracetool.format.begin(events)
tracetool.backend.<backend>.<format>(non-disabled events events)
tracetool.format.<format>.nop(disabled events events)
tracetool.format.end(events)
>>> As the next step with this patch series we could drop this patch. It
>>> doesn't make an external difference. Then we can continue to discuss
>>> how to best handle backends as a separate patch.
>>
>> WDYT of the organization above? Given the current code it's pretty simple to
>> split it into different modules. If everybody agrees on the above, I can
>> make it
>> happen.
> I like the organization you have proposed.
> In order to avoid rebasing and porting too many fixes from tracetool
> to tracetool.py I suggest you resend this series without the
> format/backend consolidation code. I can merge this series quickly
> and we can handle the format/backend consolidation code in a separate
> patch series.
Sure, I'll try to do it later today or tomorrow otherwise.
Lluis
--
"And it's much the same thing with knowledge, for whenever you learn
something new, the whole world becomes that much richer."
-- The Princess of Pure Reason, as told by Norton Juster in The Phantom
Tollbooth
