source: vendor/python/2.5/Python/importdl.c

/* Support for dynamic loading of extension modules */

#include "Python.h"

/* ./configure sets HAVE_DYNAMIC_LOADING if dynamic loading of modules is
   supported on this platform. configure will then compile and link in one
   of the dynload_*.c files, as appropriate. We will call a function in
   those modules to get a function pointer to the module's init function.
*/
#ifdef HAVE_DYNAMIC_LOADING

#include "importdl.h"

extern dl_funcptr _PyImport_GetDynLoadFunc(const char *name,
                                           const char *shortname,
                                           const char *pathname, FILE *fp);



PyObject *
_PyImport_LoadDynamicModule(char *name, char *pathname, FILE *fp)
{
        PyObject *m;
        char *lastdot, *shortname, *packagecontext, *oldcontext;
        dl_funcptr p;

        if ((m = _PyImport_FindExtension(name, pathname)) != NULL) {
                Py_INCREF(m);
                return m;
        }
        lastdot = strrchr(name, '.');
        if (lastdot == NULL) {
                packagecontext = NULL;
                shortname = name;
        }
        else {
                packagecontext = name;
                shortname = lastdot+1;
        }

        p = _PyImport_GetDynLoadFunc(name, shortname, pathname, fp);
        if (PyErr_Occurred())
                return NULL;
        if (p == NULL) {
                PyErr_Format(PyExc_ImportError,
                   "dynamic module does not define init function (init%.200s)",
                             shortname);
                return NULL;
        }
        oldcontext = _Py_PackageContext;
        _Py_PackageContext = packagecontext;
        (*p)();
        _Py_PackageContext = oldcontext;
        if (PyErr_Occurred())
                return NULL;

        m = PyDict_GetItemString(PyImport_GetModuleDict(), name);
        if (m == NULL) {
                PyErr_SetString(PyExc_SystemError,
                                "dynamic module not initialized properly");
                return NULL;
        }
        /* Remember the filename as the __file__ attribute */
        if (PyModule_AddStringConstant(m, "__file__", pathname) < 0)
                PyErr_Clear(); /* Not important enough to report */

        if (_PyImport_FixupExtension(name, pathname) == NULL)
                return NULL;
        if (Py_VerboseFlag)
                PySys_WriteStderr(
                        "import %s # dynamically loaded from %s\n",
                        name, pathname);
        Py_INCREF(m);
        return m;
}

#endif /* HAVE_DYNAMIC_LOADING */