twisted.python.sendmsg is a CPython C-extension

	Alex reported
Trac ID	trac#6874
Type	enhancement
Created	2013-12-13 18:25:25Z
Branch	https://github.com/twisted/twisted/tree/port-sendmsg-to-cffi-6874

This means it isn't portable to other Python VMs, such as PyPy. It also means it's C-code.

Both of these can be alleviated by porting it to use cffi, which is portable to PyPy and CPython, and also doesn't involve writing C code.

Attachments:

• t6874.diff (25433 bytes) - added by Alex on 2013-12-13 18:26:55Z - Initial port. There's probably some platform specific stuff that the buildbots will help us sort out. Also the packaging angle.
• t6874.2.diff (27186 bytes) - added by Alex on 2013-12-15 17:33:03Z - The patch now includes packaging thingies and exposes all of the cross-platform constants that the C version did.
• t6874-2.diff (2484 bytes) - added by Alex on 2013-12-21 23:07:52Z - Now does platform checks to find teh widths of various struct members.

trac-id__6874 6874
type__enhancement enhancement
reporter__Alex Alex
priority__normal normal
milestone__ 
branch__branches_port_sendmsg_to_cffi_6874 branches/port-sendmsg-to-cffi-6874
branch_author__hynek hynek
status__new new
resolution__None None
component__core core
keywords__ 
time__1386959125000000 1386959125000000
changetime__1390428700000000 1390428700000000
version__None None
owner__Alex Alex
cc__hynek

Start with the twisted.python.sendmsg entry point and the port-sendmsg-to-cffi-6874 branch, then review the attached patches for the existing port. Check the platform-specific struct-width handling, exposed constants, and packaging changes. Done means the C extension is replaced with a portable cffi implementation while preserving the existing API across CPython and PyPy.