cpython/Modules/_testcapimodule.c

/*
 * C Extension module to test Python interpreter C APIs.
 *
 * The 'test_*' functions exported by this module are run as part of the
 * standard Python regression test, via Lib/test/test_capi.py.
 */

#include "Python.h"

static PyObject *TestError;	/* set to exception object in init */

/* Test #defines from config.h (particularly the SIZEOF_* defines).

   The ones derived from autoconf on the UNIX-like OSes can be relied
   upon (in the absence of sloppy cross-compiling), but the Windows
   platforms have these hardcoded.  Better safe than sorry.
*/
static PyObject*
sizeof_error(const char* fatname, const char* typename,
        int expected, int got)
{
	char buf[1024];
	sprintf(buf, "%s #define == %d but sizeof(%s) == %d",
		fatname, expected, typename, got);
	PyErr_SetString(TestError, buf);
	return (PyObject*)NULL;
}

static PyObject*
test_config(PyObject *self, PyObject *args)
{
        if (!PyArg_ParseTuple(args, ":test_config"))
                return NULL;

#define CHECK_SIZEOF(FATNAME, TYPE) \
	    if (FATNAME != sizeof(TYPE)) \
    	    	return sizeof_error(#FATNAME, #TYPE, FATNAME, sizeof(TYPE))

	CHECK_SIZEOF(SIZEOF_INT, int);
	CHECK_SIZEOF(SIZEOF_LONG, long);
	CHECK_SIZEOF(SIZEOF_VOID_P, void*);
	CHECK_SIZEOF(SIZEOF_TIME_T, time_t);
#ifdef HAVE_LONG_LONG
	CHECK_SIZEOF(SIZEOF_LONG_LONG, LONG_LONG);
#endif

#undef CHECK_SIZEOF

	Py_INCREF(Py_None);
	return Py_None;
}

static PyMethodDef TestMethods[] = {
	{"test_config", test_config, METH_VARARGS},
	{NULL, NULL} /* sentinel */
};

DL_EXPORT(void)
init_testcapi(void)
{
	PyObject *m, *d;

	m = Py_InitModule("_testcapi", TestMethods);

	TestError = PyErr_NewException("_testcapi.error", NULL, NULL);
	d = PyModule_GetDict(m);
	PyDict_SetItemString(d, "error", TestError);
}