[Python-Dev] [Python-checkins] cpython: _PyImport_LoadDynamicModule() encodes the module name explicitly to ASCII

[Jim Jewett]

Are you asserting that all foreign modules (or at least all handled by
this) are in C, as opposed to C++ or even Java or Fortran?  (And the C
won't change?)

Is this ASCII restriction (as opposed to even UTF8) really needed?

Or are you just saying that we need to create an ASCII name for passing to C?

-jJ

On 5/7/11, victor.stinner <python-checkins at python.org> wrote:
> http://hg.python.org/cpython/rev/eb003c3d1770
> changeset:   69889:eb003c3d1770
> user:        Victor Stinner <victor.stinner at haypocalc.com>
> date:        Sat May 07 12:46:05 2011 +0200
> summary:
>   _PyImport_LoadDynamicModule() encodes the module name explicitly to ASCII
>
> The 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.
>
> files:
>   Python/importdl.c |  40 +++++++++++++++++++++-------------
>   1 files changed, 25 insertions(+), 15 deletions(-)
>
>
> diff --git a/Python/importdl.c b/Python/importdl.c
> --- a/Python/importdl.c
> +++ b/Python/importdl.c
> @@ -20,31 +20,36 @@
>                                             const char *pathname, FILE *fp);
>  #endif
>
> -/* name should be ASCII only because the C language doesn't accept
> non-ASCII
> -   identifiers, and dynamic modules are written in C. */
> -
>  PyObject *
>  _PyImport_LoadDynamicModule(PyObject *name, PyObject *path, FILE *fp)
>  {
> -    PyObject *m;
> +    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;
>
> -    namestr = _PyUnicode_AsString(name);
> -    if (namestr == NULL)
> -        return NULL;
> -
>      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;
> @@ -60,34 +65,33 @@
>  #else
>      pathbytes = PyUnicode_EncodeFSDefault(path);
>      if (pathbytes == NULL)
> -        return NULL;
> +        goto error;
>      p0 = _PyImport_GetDynLoadFunc(shortname,
>                                    PyBytes_AS_STRING(pathbytes), fp);
>      Py_DECREF(pathbytes);
>  #endif
>      p = (PyObject*(*)(void))p0;
>      if (PyErr_Occurred())
> -        return NULL;
> +        goto error;
>      if (p == NULL) {
>          PyErr_Format(PyExc_ImportError,
>                       "dynamic module does not define init function"
>                       " (PyInit_%s)",
>                       shortname);
> -        return NULL;
> +        goto error;
>      }
>      oldcontext = _Py_PackageContext;
>      _Py_PackageContext = packagecontext;
>      m = (*p)();
>      _Py_PackageContext = oldcontext;
>      if (m == NULL)
> -        return NULL;
> +        goto error;
>
>      if (PyErr_Occurred()) {
> -        Py_DECREF(m);
>          PyErr_Format(PyExc_SystemError,
>                       "initialization of %s raised unreported exception",
>                       shortname);
> -        return NULL;
> +        goto error;
>      }
>
>      /* Remember pointer to module init function. */
> @@ -101,12 +105,18 @@
>          Py_INCREF(path);
>
>      if (_PyImport_FixupExtensionObject(m, name, path) < 0)
> -        return NULL;
> +        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 */
>
> --
> Repository URL: http://hg.python.org/cpython
>