fix a crasher with uninitialized canvas field abstraction names

pd/src/g_canvas.h

@@ -258,7 +258,7 @@ typedef struct _dataslot
 {
     int ds_type;
     t_symbol *ds_name;
-    t_symbol *ds_fieldtemplate;     /* filled in for arrays only */
+    t_symbol *ds_fieldtemplate;     /* filled in only for array/canvas fields */
     t_binbuf *ds_binbuf;            /* binbuf of an abstraction to be loaded */
 } t_dataslot;
 

pd/src/g_readwrite.c

@@ -787,8 +787,10 @@ static void canvas_savetemplatesto(t_canvas *x, t_binbuf *b, int wholething)
                 case DT_TEXT: type = gensym("text"); break; //&s_list; break;
                 default: type = &s_float; bug("canvas_write");
             }
-            if (template->t_vec[j].ds_type == DT_ARRAY ||
-                template->t_vec[j].ds_type == DT_LIST)
+            if (template->t_vec[j].ds_type == DT_LIST)
+                binbuf_addv(b, "sss", type, template->t_vec[j].ds_name,
+                    gensym(template->t_vec[j].ds_fieldtemplate->s_name));
+            else if (template->t_vec[j].ds_type == DT_ARRAY)
                 binbuf_addv(b, "sss", type, template->t_vec[j].ds_name,
                     gensym(template->t_vec[j].ds_fieldtemplate->s_name + 3));
             else binbuf_addv(b, "ss", type, template->t_vec[j].ds_name);

pd/src/g_template.c

@@ -96,8 +96,9 @@ t_template *template_new(t_symbol *templatesym, int argc, t_atom *argv)
                 pd_error(x, "canvas lacks template or name");
                 goto bad;
             }
-            /* If we keep the canvas field API this needs to be revisited */
-            //filename = canvas_makebindsym(argv[2].a_w.w_symbol);
+            /* We're abusing newarraytemplate here to store the name of
+               the abstraction (minus the .pd extension) */
+            newarraytemplate = argv[2].a_w.w_symbol;
             sprintf(filename, "%s.pd", argv[2].a_w.w_symbol->s_name);
             if (binbuf_read_via_canvas(b, filename, canvas_getcurrent(), 0))
                 post("warning: abstraction %s not found", filename);