from qmsk.net.libc cimport *
from qmsk.net.py cimport raise_errno

cdef fcntl_set_flag (int fd, int flag, bint value) :
    """
        Set the given FCNTL file status flag(s) to the given boolean value.

        This will first get the current flags, then compute the new flags, and then update them if they have changed.
    """
    
    # get current flags
    cdef int old_flags = fcntl(fd, F_GETFL, 0)

    if old_flags < 0 :
        raise_errno('fcntl')

    # set bit
    cdef int new_flags = (old_flags & ~flag) | (flag if value else 0)
    
    if new_flags != old_flags :
        # set flags
        if fcntl(fd, F_SETFL, new_flags) :
            raise_errno('fcntl')


#cdef class Errno (py.OSError) :
#    def __init__ (self, func) :
#        self.func = func
#        self.err = errno
#        self.strerror = strerror(errno)
#
#    def __str__ (self) :
#        return "%s: %s" % (self.func, self.strerror)
#
#cdef class GAIError (py.OSError) :
#    def __init__ (self, func, err) :
#        self.func = func
#        self.err = err
#        self.strerror = gai_strerror(err)
#
#    def __str__ (self) :
#        return "%s: %s" % (self.func, self.strerror)
#