cpython/Python/importdl.c

123 lines
3.4 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"
#ifdef MS_WINDOWS
extern dl_funcptr _PyImport_GetDynLoadWindows(const char *shortname,
PyObject *pathname, FILE *fp);
#else
extern dl_funcptr _PyImport_GetDynLoadFunc(const char *shortname,
const char *pathname, FILE *fp);
#endif
PyObject *
_PyImport_LoadDynamicModule(PyObject *name, PyObject *path, FILE *fp)
{
PyObject *m = NULL;
#ifndef MS_WINDOWS
PyObject *pathbytes;
#endif
PyObject *nameascii;
char *namestr, *lastdot, *shortname, *packagecontext, *oldcontext;
dl_funcptr p0;
PyObject* (*p)(void);
struct PyModuleDef *def;
m = _PyImport_FindExtensionObject(name, path);
if (m != NULL) {
Py_INCREF(m);
return m;
}
/* name must be encodable to ASCII because dynamic module must have a
function called "PyInit_NAME", they are written in C, and the C language
doesn't accept non-ASCII identifiers. */
nameascii = PyUnicode_AsEncodedString(name, "ascii", NULL);
if (nameascii == NULL)
return NULL;
namestr = PyBytes_AS_STRING(nameascii);
if (namestr == NULL)
goto error;
lastdot = strrchr(namestr, '.');
if (lastdot == NULL) {
packagecontext = NULL;
shortname = namestr;
}
else {
packagecontext = namestr;
shortname = lastdot+1;
}
#ifdef MS_WINDOWS
p0 = _PyImport_GetDynLoadWindows(shortname, path, fp);
#else
pathbytes = PyUnicode_EncodeFSDefault(path);
if (pathbytes == NULL)
goto error;
p0 = _PyImport_GetDynLoadFunc(shortname,
PyBytes_AS_STRING(pathbytes), fp);
Py_DECREF(pathbytes);
#endif
p = (PyObject*(*)(void))p0;
if (PyErr_Occurred())
goto error;
if (p == NULL) {
PyErr_Format(PyExc_ImportError,
"dynamic module does not define init function"
" (PyInit_%s)",
shortname);
goto error;
}
oldcontext = _Py_PackageContext;
_Py_PackageContext = packagecontext;
m = (*p)();
_Py_PackageContext = oldcontext;
if (m == NULL)
goto error;
if (PyErr_Occurred()) {
PyErr_Format(PyExc_SystemError,
"initialization of %s raised unreported exception",
shortname);
goto error;
}
/* Remember pointer to module init function. */
def = PyModule_GetDef(m);
def->m_base.m_init = p;
/* Remember the filename as the __file__ attribute */
if (PyModule_AddObject(m, "__file__", path) < 0)
PyErr_Clear(); /* Not important enough to report */
else
Py_INCREF(path);
if (_PyImport_FixupExtensionObject(m, name, path) < 0)
goto error;
if (Py_VerboseFlag)
PySys_FormatStderr(
"import %U # dynamically loaded from %R\n",
name, path);
Py_DECREF(nameascii);
return m;
error:
Py_DECREF(nameascii);
Py_XDECREF(m);
return NULL;
}
#endif /* HAVE_DYNAMIC_LOADING */