cpython/Python/importdl.c
Guido van Rossum ae9e7960d3 SF patch #471839: Bug when extensions import extensions (Shane Hathaway)
When an extension imports another extension in its
    initXXX() function, the variable _Py_PackageContext is
    prematurely reset to NULL. If the outer extension then
    calls Py_InitModule(), the extension is installed in
    sys.modules without its package name. The
    manifestation of this bug is a "SystemError:
    _PyImport_FixupExtension: module <package>.<extension>
    not loaded".

    To fix this, importdl.c just needs to retain the old
    value of _Py_PackageContext and restore it after the
    initXXX() method is called. The attached patch does this.

    This patch applies to Python 2.1.1 and the current CVS.
2001-10-16 20:07:34 +00:00

81 lines
2.0 KiB
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, *d, *s;
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;
if (_PyImport_FixupExtension(name, pathname) == NULL)
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 */
d = PyModule_GetDict(m);
s = PyString_FromString(pathname);
if (s == NULL || PyDict_SetItemString(d, "__file__", s) != 0)
PyErr_Clear(); /* Not important enough to report */
Py_XDECREF(s);
if (Py_VerboseFlag)
PySys_WriteStderr(
"import %s # dynamically loaded from %s\n",
name, pathname);
Py_INCREF(m);
return m;
}
#endif /* HAVE_DYNAMIC_LOADING */