diff options
Diffstat (limited to 'gi/pygi-closure.c')
| -rw-r--r-- | gi/pygi-closure.c | 314 |
1 files changed, 311 insertions, 3 deletions
diff --git a/gi/pygi-closure.c b/gi/pygi-closure.c index 5df4713e..3dd73da9 100644 --- a/gi/pygi-closure.c +++ b/gi/pygi-closure.c @@ -14,12 +14,23 @@ * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public - * License along with this library; if not, write to the Free Software - * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 - * USA + * License along with this library; if not, see <http://www.gnu.org/licenses/>. */ #include "pygi-private.h" +#include "pygi-closure.h" + + +typedef struct _PyGICallbackCache +{ + PyGIArgCache arg_cache; + gssize user_data_index; + gssize destroy_notify_index; + GIScopeType scope; + GIInterfaceInfo *interface_info; +} PyGICallbackCache; + +static PyGICClosure *global_destroy_notify; /* This maintains a list of closures which can be free'd whenever as they have been called. We will free them on the next @@ -669,3 +680,300 @@ _pygi_make_native_closure (GICallableInfo* info, return closure; } + +/* _pygi_destroy_notify_dummy: + * + * Dummy method used in the occasion when a method has a GDestroyNotify + * argument without user data. + */ +static void +_pygi_destroy_notify_dummy (gpointer data) { +} + +static void +_pygi_destroy_notify_callback_closure (ffi_cif *cif, + void *result, + void **args, + void *data) +{ + PyGICClosure *info = * (void**) (args[0]); + + g_assert (info); + + _pygi_invoke_closure_free (info); +} + +/* _pygi_destroy_notify_create: + * + * Method used in the occasion when a method has a GDestroyNotify + * argument with user data. + */ +static PyGICClosure* +_pygi_destroy_notify_create (void) +{ + if (!global_destroy_notify) { + + PyGICClosure *destroy_notify = g_slice_new0 (PyGICClosure); + GIBaseInfo* glib_destroy_notify; + + g_assert (destroy_notify); + + glib_destroy_notify = g_irepository_find_by_name (NULL, "GLib", "DestroyNotify"); + g_assert (glib_destroy_notify != NULL); + g_assert (g_base_info_get_type (glib_destroy_notify) == GI_INFO_TYPE_CALLBACK); + + destroy_notify->closure = g_callable_info_prepare_closure ( (GICallableInfo*) glib_destroy_notify, + &destroy_notify->cif, + _pygi_destroy_notify_callback_closure, + NULL); + + global_destroy_notify = destroy_notify; + } + + return global_destroy_notify; +} + +static gboolean +_pygi_marshal_from_py_interface_callback (PyGIInvokeState *state, + PyGICallableCache *callable_cache, + PyGIArgCache *arg_cache, + PyObject *py_arg, + GIArgument *arg, + gpointer *cleanup_data) +{ + GICallableInfo *callable_info; + PyGICClosure *closure; + PyGIArgCache *user_data_cache = NULL; + PyGIArgCache *destroy_cache = NULL; + PyGICallbackCache *callback_cache; + PyObject *py_user_data = NULL; + + callback_cache = (PyGICallbackCache *)arg_cache; + + if (callback_cache->user_data_index > 0) { + user_data_cache = _pygi_callable_cache_get_arg (callable_cache, callback_cache->user_data_index); + if (user_data_cache->py_arg_index < state->n_py_in_args) { + /* py_user_data is a borrowed reference. */ + py_user_data = PyTuple_GetItem (state->py_in_args, user_data_cache->py_arg_index); + if (!py_user_data) + return FALSE; + /* NULL out user_data if it was not supplied and the default arg placeholder + * was used instead. + */ + if (py_user_data == _PyGIDefaultArgPlaceholder) { + py_user_data = NULL; + } else if (callable_cache->user_data_varargs_index < 0) { + /* For non-variable length user data, place the user data in a + * single item tuple which is concatenated to the callbacks arguments. + * This allows callback input arg marshaling to always expect a + * tuple for user data. Note the + */ + py_user_data = Py_BuildValue("(O)", py_user_data, NULL); + } else { + /* increment the ref borrowed from PyTuple_GetItem above */ + Py_INCREF (py_user_data); + } + } + } + + if (py_arg == Py_None) { + return TRUE; + } + + if (!PyCallable_Check (py_arg)) { + PyErr_Format (PyExc_TypeError, + "Callback needs to be a function or method not %s", + py_arg->ob_type->tp_name); + + return FALSE; + } + + callable_info = (GICallableInfo *)callback_cache->interface_info; + + closure = _pygi_make_native_closure (callable_info, callback_cache->scope, py_arg, py_user_data); + arg->v_pointer = closure->closure; + + /* always decref the user data as _pygi_make_native_closure adds its own ref */ + Py_XDECREF (py_user_data); + + /* The PyGICClosure instance is used as user data passed into the C function. + * The return trip to python will marshal this back and pull the python user data out. + */ + if (user_data_cache != NULL) { + state->in_args[user_data_cache->c_arg_index].v_pointer = closure; + } + + /* Setup a GDestroyNotify callback if this method supports it along with + * a user data field. The user data field is a requirement in order + * free resources and ref counts associated with this arguments closure. + * In case a user data field is not available, show a warning giving + * explicit information and setup a dummy notification to avoid a crash + * later on in _pygi_destroy_notify_callback_closure. + */ + if (callback_cache->destroy_notify_index > 0) { + destroy_cache = _pygi_callable_cache_get_arg (callable_cache, callback_cache->destroy_notify_index); + } + + if (destroy_cache) { + if (user_data_cache != NULL) { + PyGICClosure *destroy_notify = _pygi_destroy_notify_create (); + state->in_args[destroy_cache->c_arg_index].v_pointer = destroy_notify->closure; + } else { + gchar *msg = g_strdup_printf("Callables passed to %s will leak references because " + "the method does not support a user_data argument. " + "See: https://bugzilla.gnome.org/show_bug.cgi?id=685598", + callable_cache->name); + if (PyErr_WarnEx(PyExc_RuntimeWarning, msg, 2)) { + g_free(msg); + _pygi_invoke_closure_free(closure); + return FALSE; + } + g_free(msg); + state->in_args[destroy_cache->c_arg_index].v_pointer = _pygi_destroy_notify_dummy; + } + } + + /* Use the PyGIClosure as data passed to cleanup for GI_SCOPE_TYPE_CALL. */ + *cleanup_data = closure; + + return TRUE; +} + +static PyObject * +_pygi_marshal_to_py_interface_callback (PyGIInvokeState *state, + PyGICallableCache *callable_cache, + PyGIArgCache *arg_cache, + GIArgument *arg) +{ + PyObject *py_obj = NULL; + + PyErr_Format (PyExc_NotImplementedError, + "Marshalling a callback to PyObject is not supported"); + return py_obj; +} + +static void +_callback_cache_free_func (PyGICallbackCache *cache) +{ + if (cache != NULL) { + if (cache->interface_info != NULL) + g_base_info_unref ( (GIBaseInfo *)cache->interface_info); + + g_slice_free (PyGICallbackCache, cache); + } +} + +static void +_pygi_marshal_cleanup_from_py_interface_callback (PyGIInvokeState *state, + PyGIArgCache *arg_cache, + PyObject *py_arg, + gpointer data, + gboolean was_processed) +{ + PyGICallbackCache *callback_cache = (PyGICallbackCache *)arg_cache; + if (was_processed && callback_cache->scope == GI_SCOPE_TYPE_CALL) { + _pygi_invoke_closure_free (data); + } +} + +static void +_arg_cache_from_py_interface_callback_setup (PyGIArgCache *arg_cache, + PyGICallableCache *callable_cache) +{ + PyGICallbackCache *callback_cache = (PyGICallbackCache *)arg_cache; + if (callback_cache->user_data_index >= 0) { + PyGIArgCache *user_data_arg_cache = _arg_cache_alloc (); + user_data_arg_cache->meta_type = PYGI_META_ARG_TYPE_CHILD_WITH_PYARG; + user_data_arg_cache->direction = PYGI_DIRECTION_FROM_PYTHON; + user_data_arg_cache->has_default = TRUE; /* always allow user data with a NULL default. */ + _pygi_callable_cache_set_arg (callable_cache, callback_cache->user_data_index, + user_data_arg_cache); + } + + if (callback_cache->destroy_notify_index >= 0) { + PyGIArgCache *destroy_arg_cache = _arg_cache_alloc (); + destroy_arg_cache->meta_type = PYGI_META_ARG_TYPE_CHILD; + destroy_arg_cache->direction = PYGI_DIRECTION_FROM_PYTHON; + _pygi_callable_cache_set_arg (callable_cache, callback_cache->destroy_notify_index, + destroy_arg_cache); + } + arg_cache->from_py_marshaller = _pygi_marshal_from_py_interface_callback; + arg_cache->from_py_cleanup = _pygi_marshal_cleanup_from_py_interface_callback; +} + + +static gboolean +pygi_arg_callback_setup_from_info (PyGICallbackCache *arg_cache, + GITypeInfo *type_info, + GIArgInfo *arg_info, /* may be null */ + GITransfer transfer, + PyGIDirection direction, + GIInterfaceInfo *iface_info, + PyGICallableCache *callable_cache) +{ + gssize child_offset = 0; + + if (!pygi_arg_base_setup ((PyGIArgCache *)arg_cache, + type_info, + arg_info, + transfer, + direction)) { + return FALSE; + } + + if (direction & PYGI_DIRECTION_TO_PYTHON) { + ((PyGIArgCache *)arg_cache)->to_py_marshaller = _pygi_marshal_to_py_interface_callback; + } + + if (callable_cache != NULL) + child_offset = + (callable_cache->function_type == PYGI_FUNCTION_TYPE_METHOD || + callable_cache->function_type == PYGI_FUNCTION_TYPE_VFUNC) ? 1: 0; + + ( (PyGIArgCache *)arg_cache)->destroy_notify = (GDestroyNotify)_callback_cache_free_func; + + arg_cache->user_data_index = g_arg_info_get_closure (arg_info); + if (arg_cache->user_data_index != -1) + arg_cache->user_data_index += child_offset; + arg_cache->destroy_notify_index = g_arg_info_get_destroy (arg_info); + if (arg_cache->destroy_notify_index != -1) + arg_cache->destroy_notify_index += child_offset; + arg_cache->scope = g_arg_info_get_scope (arg_info); + g_base_info_ref( (GIBaseInfo *)iface_info); + arg_cache->interface_info = iface_info; + + if (direction & PYGI_DIRECTION_FROM_PYTHON) + _arg_cache_from_py_interface_callback_setup ((PyGIArgCache *)arg_cache, callable_cache); + + return TRUE; +} + +PyGIArgCache * +pygi_arg_callback_new_from_info (GITypeInfo *type_info, + GIArgInfo *arg_info, /* may be null */ + GITransfer transfer, + PyGIDirection direction, + GIInterfaceInfo *iface_info, + PyGICallableCache *callable_cache) +{ + gboolean res = FALSE; + PyGICallbackCache *callback_cache; + + callback_cache = g_slice_new0 (PyGICallbackCache); + if (callback_cache == NULL) + return NULL; + + res = pygi_arg_callback_setup_from_info (callback_cache, + type_info, + arg_info, + transfer, + direction, + iface_info, + callable_cache); + if (res) { + return (PyGIArgCache *)callback_cache; + } else { + _pygi_arg_cache_free ((PyGIArgCache *)callback_cache); + return NULL; + } +} |