On Tue, Feb 14, 2012 at 8:13 PM, Stefan Behnel <stefan...@behnel.de> wrote: > Maciej Fijalkowski, 14.02.2012 19:00: >> On Tue, Feb 14, 2012 at 7:56 PM, Stefan Behnel wrote: >>> Amaury Forgeot d'Arc, 14.02.2012 18:45: >>>> 2012/2/14 Stefan Behnel >>>>> if PyPy can't come up with a fast way to >>>>> interface with C code, it's bound to die. >>>> >>>> But it certainly can! For example PyPy implements the _ssl and pyexpat >>>> modules, >>>> which are interfaces to the openssl and expat libraries. >>>> And it does that by generating C code that calls the corresponding >>>> functions. >>>> >>>> See for example the code for SSLObject.write(): >>>> https://bitbucket.org/pypy/pypy/src/default/pypy/module/_ssl/interp_ssl.py#cl-157 >>>> it calls the C function SSL_write(), which is declared like this: >>>> https://bitbucket.org/pypy/pypy/src/default/pypy/rlib/ropenssl.py#cl-255 >>>> This kind of code is not difficult to write (in this case, it's a simple >>>> translation of >>>> CPython modules) and is close enough to C when you really need it. >>>> For example, it's possible to use macros when they look like function >>>> calls, >>>> or embed C snippets. >>> >>> Ok, then I take it that this would be the preferred Python+FFI approach for >>> interfacing, right? ctypes is out of the loop? >> >> Ideally it would be a better FFI than ctypes in my opinion. > > Erm, what do you mean by "ideally"? Would you not consider rffi usable or > ready enough for being used for this? Do you mean there should be yet > another FFI? > > Simple questions: > > Is rffi usable in this context or is it not? Does it require RPython code > to be generated or does it also work with Python code? How do callbacks > work in rffi? Does rffi provide access to PyPy objects? And how so? > > I don't know all that much about RPython. Would it work to generate RPython > from Cython? Is there a transformation to map regular Python code down to > RPython? (e.g. by renaming variables, templating, specialising, etc.) > > Stefan > > _______________________________________________ > pypy-dev mailing list > pypy-dev@python.org > http://mail.python.org/mailman/listinfo/pypy-dev
Rffi is an internal RPython detail, it works before compilation but only as a testing layer. People should not use it (at least right now). Maybe it's actually reusable as an API, but needs to be extracted a bit from pypy in order to work on top of python (it imports something like 3/4 of pypy source tree). It also only works by a very hackish layer on top of ctypes and it's surely not efficient. I imagine something slightly better that does roughly the same but does not have to be RPython. Cheers, fijal _______________________________________________ pypy-dev mailing list pypy-dev@python.org http://mail.python.org/mailman/listinfo/pypy-dev
