Refactor _from server socket

cheroot/connections.py

@@ -295,6 +295,44 @@ def _remove_invalid_sockets(self):
             with _cm.suppress(OSError):
                 conn.close()
 
+    def _setup_conn_addr(self, conn, s, addr):
+        """Configure remote address and port for the connection.
+
+        Populates the connection object with remote address metadata.
+        If the address is unavailable following the handshake, this
+        method detects the socket's address family (IPv4/IPv6)
+        and provides an appropriate 'any' address placeholder.
+        """
+        # optional values
+        # Until we do DNS lookups, omit REMOTE_HOST
+        if addr is None:  # sometimes this can happen
+            # figure out if AF_INET or AF_INET6.
+            if len(s.getsockname()) == 2:
+                # AF_INET
+                addr = ('0.0.0.0', 0)
+            else:
+                # AF_INET6
+                addr = ('::', 0)
+        conn.remote_addr = addr[0]
+        conn.remote_port = addr[1]
+
+    def _ignore_socket_oserror(self, exc):
+        if self.server.stats['Enabled']:
+            self.server.stats['Socket Errors'] += 1
+        err_code = exc.args[0]
+
+        # EINTR should occur when a signal is received during accept();
+        # retry the call. See https://github.com/cherrypy/cherrypy/issues/707.
+        is_eintr = err_code in errors.socket_error_eintr
+
+        # Just try again. See https://github.com/cherrypy/cherrypy/issues/479.
+        is_nonblocking = err_code in errors.socket_errors_nonblocking
+
+        # Our socket was closed. See https://github.com/cherrypy/cherrypy/issues/686.
+        is_ignored = err_code in errors.socket_errors_to_ignore
+
+        return is_eintr or is_nonblocking or is_ignored
+
     def _from_server_socket(self, server_socket):  # noqa: C901  # FIXME
         try:
             s, addr = server_socket.accept()
@@ -335,18 +373,7 @@ def _from_server_socket(self, server_socket):  # noqa: C901  # FIXME
             conn = self.server.ConnectionClass(self.server, s, mf)
 
             if not isinstance(self.server.bind_addr, (str, bytes)):
-                # optional values
-                # Until we do DNS lookups, omit REMOTE_HOST
-                if addr is None:  # sometimes this can happen
-                    # figure out if AF_INET or AF_INET6.
-                    if len(s.getsockname()) == 2:
-                        # AF_INET
-                        addr = ('0.0.0.0', 0)
-                    else:
-                        # AF_INET6
-                        addr = ('::', 0)
-                conn.remote_addr = addr[0]
-                conn.remote_port = addr[1]
+                self._setup_conn_addr(conn, s, addr)
 
             conn.ssl_env = ssl_env
             return conn
@@ -356,24 +383,8 @@ def _from_server_socket(self, server_socket):  # noqa: C901  # FIXME
             # notice keyboard interrupts on Win32, which don't interrupt
             # accept() by default
             return None
-        except OSError as ex:
-            if self.server.stats['Enabled']:
-                self.server.stats['Socket Errors'] += 1
-            if ex.args[0] in errors.socket_error_eintr:
-                # I *think* this is right. EINTR should occur when a signal
-                # is received during the accept() call; all docs say retry
-                # the call, and I *think* I'm reading it right that Python
-                # will then go ahead and poll for and handle the signal
-                # elsewhere. See
-                # https://github.com/cherrypy/cherrypy/issues/707.
-                return None
-            if ex.args[0] in errors.socket_errors_nonblocking:
-                # Just try again. See
-                # https://github.com/cherrypy/cherrypy/issues/479.
-                return None
-            if ex.args[0] in errors.socket_errors_to_ignore:
-                # Our socket was closed.
-                # See https://github.com/cherrypy/cherrypy/issues/686.
+        except OSError as exc:
+            if self._ignore_socket_oserror(exc):
                 return None
             raise