python socketmodule exposure to cython

socket.pxd

from cpython.time cimport PyTime_t, PyTime_AsSecondsDouble
from cpython.object cimport PyObject, PyTypeObject

# After carefully observing socketmodule.h over from CPython and some 
# different versions of python I've determined it might be possible to 
# expose this data to the cython api by simply copying off socketmodule.h

# NOTE: Some macros that could be utilized however were too dynamic to 
# be utilized here. However just getting the file descriptor object means a lot
# and has potential of being utilized with libraries such as winloop/uvloop for 
# extra speed in the future.

cdef extern from "socketmodule.h":
    ctypedef int SOCKET_T

    ctypedef struct PySocketSockObject:
        SOCKET_T sock_fd # Socket file descriptor
        int sock_family       # Address family, e.g., AF_INET
        int sock_type         # Socket type, e.g., SOCK_STREAM
        int sock_proto        # Protocol type, usually 0
        PyObject* (*errorhandler)() except NULL # Error handler; checks
                                         #   errno, returns NULL and
                                         #   sets a Python exception
        PyTime_t sock_timeout       # Operation timeout in seconds
                                        # 0.0 means non-blocking
    
    ctypedef struct PySocketModule_APIObject:
        PyTypeObject *Sock_Type
        PyObject *error
        PyObject *timeout_error
    
    PySocketModule_APIObject* PySocketModule_ImportModuleAndAPI()

    ctypedef class _socket.socket [object PySocketSockObject, check_size ignore]:
        cdef:
            # Reason for making the majortiy of these constant is to prevent fiddling
            # with sockets from python's end.
            @property
            cdef const SOCKET_T fd(self):
                return self.sock_fd

            @property
            cdef const int family(self):
                return self.sock_family
            
            @property
            cdef const int type(self):
                return self.sock_type
            
            @property
            cdef double timeout(self):
                return PyTime_AsSecondsDouble(self.sock_type)