gh-135748: Use Argument Clinic for more socket functions (GH-155257)

Convert all convertible functions and methods of the socket module.
They now have signatures for introspection, and functions which take
several arguments use METH_FASTCALL instead of METH_VARARGS.

ioctl(), sendto() and setsockopt() are left as they are.  Their
behaviour depends on the number of the arguments or on the value of a
preceding argument, which Argument Clinic cannot express.

Author: serhiy-storchaka

Include/internal/pycore_global_objects_fini_generated.h

@@ -319,6 +319,7 @@ struct _Py_global_strings {
         STRUCT_FOR_ID(argv)
         STRUCT_FOR_ID(as_integer_ratio)
         STRUCT_FOR_ID(asend)
+        STRUCT_FOR_ID(assoclen)
         STRUCT_FOR_ID(ast)
         STRUCT_FOR_ID(athrow)
         STRUCT_FOR_ID(attr)
@@ -534,6 +535,7 @@ struct _Py_global_strings {
         STRUCT_FOR_ID(headers)
         STRUCT_FOR_ID(hi)
         STRUCT_FOR_ID(hook)
+        STRUCT_FOR_ID(host)
         STRUCT_FOR_ID(hour)
         STRUCT_FOR_ID(hours)
         STRUCT_FOR_ID(id)
@@ -582,6 +584,7 @@ struct _Py_global_strings {
         STRUCT_FOR_ID(iter)
         STRUCT_FOR_ID(iterable)
         STRUCT_FOR_ID(iterations)
+        STRUCT_FOR_ID(iv)
         STRUCT_FOR_ID(join)
         STRUCT_FOR_ID(jump)
         STRUCT_FOR_ID(keepends)
@@ -660,6 +663,7 @@ struct _Py_global_strings {
         STRUCT_FOR_ID(namespace_separator)
         STRUCT_FOR_ID(namespaces)
         STRUCT_FOR_ID(native)
+        STRUCT_FOR_ID(nbytes)
         STRUCT_FOR_ID(ndigits)
         STRUCT_FOR_ID(nested)
         STRUCT_FOR_ID(new_file_name)
@@ -684,6 +688,7 @@ struct _Py_global_strings {
         STRUCT_FOR_ID(onceregistry)
         STRUCT_FOR_ID(only_active_thread)
         STRUCT_FOR_ID(only_keys)
+        STRUCT_FOR_ID(op)
         STRUCT_FOR_ID(oparg)
         STRUCT_FOR_ID(opcode)
         STRUCT_FOR_ID(opcodes)
@@ -718,6 +723,7 @@ struct _Py_global_strings {
         STRUCT_FOR_ID(pidfd)
         STRUCT_FOR_ID(pointer_bits)
         STRUCT_FOR_ID(policy)
+        STRUCT_FOR_ID(port)
         STRUCT_FOR_ID(pos)
         STRUCT_FOR_ID(pos1)
         STRUCT_FOR_ID(pos2)

Include/internal/pycore_global_strings.h

@@ -6328,6 +6328,25 @@ def test_signal_module_has_signatures(self):
         import signal
         self._test_module_has_signatures(signal)
 
+    def test_socket_module_has_signatures(self):
+        import socket
+        # The socket type has no signature, it is created by socket().
+        no_signature = {'SocketType'}
+        # The C default is NULL and None is not accepted
+        unsupported_signature = {'getservbyname', 'getservbyport'}
+        # Not all functions and methods are available on all platforms.
+        unsupported_signature &= vars(socket).keys()
+        # These cannot be converted to Argument Clinic: their behaviour
+        # depends on the number of the arguments.
+        methods_no_signature = {'ioctl', 'sendto', 'setsockopt'}
+        # These have parameters with unrepresentable default values.
+        methods_unsupported_signature = {'listen', 'sendmsg', 'sendmsg_afalg'}
+        defined = vars(socket.SocketType).keys()
+        self._test_module_has_signatures(socket,
+                no_signature, unsupported_signature,
+                {'SocketType': methods_no_signature & defined},
+                {'SocketType': methods_unsupported_signature & defined})
+
     def test_stat_module_has_signatures(self):
         import stat
         self._test_module_has_signatures(stat)