possible (hopeful) fix for the garbage collection bug

overviewer_core/src/main.c

@@ -17,6 +17,10 @@
 
 #include "overviewer.h"
 
+/* global variables from rendermodes.c -- both are dictionaries */
+extern PyObject *render_mode_options;
+extern PyObject *custom_render_modes;
+
 PyObject *get_extension_version(PyObject *self, PyObject *args) {
 
     return Py_BuildValue("i", OVERVIEWER_EXTENSION_VERSION);
@@ -55,9 +59,22 @@ static PyMethodDef COverviewerMethods[] = {
 PyMODINIT_FUNC
 initc_overviewer(void)
 {
-    (void)Py_InitModule("c_overviewer", COverviewerMethods);
+    PyObject *mod = Py_InitModule("c_overviewer", COverviewerMethods);
+
     /* for numpy */
     import_array();
     
+    /* create the render mode data structures, and attatch them to the module
+     * so that the Python garbage collector doesn't freak out
+     */
+    
+    render_mode_options = PyDict_New();
+    PyObject_SetAttrString(mod, "_render_mode_options", render_mode_options);
+    Py_DECREF(render_mode_options);
+    
+    custom_render_modes = PyDict_New();
+    PyObject_SetAttrString(mod, "_custom_render_modes", custom_render_modes);
+    Py_DECREF(custom_render_modes);
+    
     init_endian();
 }

overviewer_core/src/rendermodes.c

@@ -32,8 +32,8 @@ static RenderModeInterface *render_modes[] = {
     NULL
 };
 
-static PyObject *render_mode_options = NULL;
+PyObject *render_mode_options = NULL;
-static PyObject *custom_render_modes = NULL;
+PyObject *custom_render_modes = NULL;
 
 /* rendermode encapsulation */
 
@@ -43,8 +43,6 @@ render_mode_create_options(const char *mode) {
     const char *parent = NULL;
     PyObject *base_options, *ret, *parent_options;
     unsigned int i, found_concrete;
-    if (render_mode_options == NULL)
-        return PyDict_New();
     
     base_options = PyDict_GetItemString(render_mode_options, mode);
     if (base_options) {
@@ -66,7 +64,7 @@ render_mode_create_options(const char *mode) {
     }
     
     /* check custom mode info if needed */
-    if (found_concrete == 0 && custom_render_modes != NULL) {
+    if (found_concrete == 0) {
         PyObject *custom = PyDict_GetItemString(custom_render_modes, mode);
         if (custom) {
             custom = PyDict_GetItemString(custom, "parent");
@@ -106,8 +104,6 @@ render_mode_find_interface(const char *mode) {
     }
     
     /* check for custom modes */
-    if (custom_render_modes == NULL)
-        return NULL;
     custom = PyDict_GetItemString(custom_render_modes, mode);
     if (custom == NULL)
         return NULL;
@@ -236,14 +232,12 @@ PyObject *get_render_modes(PyObject *self, PyObject *args) {
         Py_DECREF(name);
     }
     
-    if (custom_render_modes != NULL) {
     PyObject *key, *value;
     Py_ssize_t pos = 0;
     
     while (PyDict_Next(custom_render_modes, &pos, &key, &value)) {
         PyList_Append(modes, key);
     }
-    }
     
     return modes;
 }
@@ -329,7 +323,6 @@ PyObject *get_render_mode_info(PyObject *self, PyObject *args) {
         }
     }
     
-    if (custom_render_modes != NULL) {
     PyObject *custom = PyDict_GetItemString(custom_render_modes, rendermode);
     if (custom) {
         PyObject *tmp, *copy = PyDict_Copy(custom);
@@ -345,7 +338,6 @@ PyObject *get_render_mode_info(PyObject *self, PyObject *args) {
         
         return copy;
     }
-    }
     
     Py_DECREF(info);
     return PyErr_Format(PyExc_ValueError, "invalid rendermode: \"%s\"", rendermode);
@@ -365,7 +357,6 @@ PyObject *get_render_mode_inheritance(PyObject *self, PyObject *args) {
         return NULL;
     
     /* take care of the chain of custom modes, if there are any */
-    if (custom_render_modes != NULL) {
     PyObject *custom = PyDict_GetItemString(custom_render_modes, rendermode);
     while (custom != NULL) {
         PyObject *name = PyString_FromString(rendermode);
@@ -376,7 +367,6 @@ PyObject *get_render_mode_inheritance(PyObject *self, PyObject *args) {
         rendermode = PyString_AsString(custom);
         custom = PyDict_GetItem(custom_render_modes, custom);
     }
-    }
     
     /* now handle concrete modes */
     for (i = 0; render_modes[i] != NULL; i++) {
@@ -423,7 +413,6 @@ PyObject *get_render_mode_children(PyObject *self, PyObject *args) {
         }
     }
     
-    if (custom_render_modes != NULL) {
     PyObject *key, *value;
     Py_ssize_t pos = 0;
     
@@ -435,7 +424,6 @@ PyObject *get_render_mode_children(PyObject *self, PyObject *args) {
             PyList_Append(children, key);
         }
     }
-    }
     
     return children;
 }
@@ -485,9 +473,6 @@ PyObject *set_render_mode_options(PyObject *self, PyObject *args) {
         }
     }
     
-    if (render_mode_options == NULL)
-        render_mode_options = PyDict_New();
-    
     PyDict_SetItemString(render_mode_options, rendermode, opts);
     Py_RETURN_NONE;
 }
@@ -498,9 +483,6 @@ PyObject *add_custom_render_mode(PyObject *self, PyObject *args) {
     if (!PyArg_ParseTuple(args, "sO!", &rendermode, &PyDict_Type, &opts))
         return NULL;
 
-    if (custom_render_modes == NULL)
-        custom_render_modes = PyDict_New();
-    
     /* first, make sure the parent is set correctly */
     pyparent = PyDict_GetItemString(opts, "parent");
     if (pyparent == NULL)