Eo: protect against recursive object destruction calls, fixes T1741

Summary:
    Eo: semantic obj->del replaced by obj->destructed
    Eo: protect against recursive object destruction calls
    Eo: add tests for bfada4b

Reviewers: JackDanielZ, tasn

Reviewed By: tasn

Subscribers: cedric

Maniphest Tasks: T1741

Differential Revision: https://phab.enlightenment.org/D1675

Fixes T1741

@fix

src/Makefile_Eo.am

@@ -121,6 +121,7 @@ tests/eo/suite/eo_suite.h \
 tests/eo/suite/eo_error_msgs.h \
 tests/eo/suite/eo_error_msgs.c \
 tests/eo/suite/eo_test_class_errors.c \
+tests/eo/suite/eo_test_class_behaviour_errors.c \
 tests/eo/suite/eo_test_call_errors.c \
 tests/eo/suite/eo_test_general.c \
 tests/eo/suite/eo_test_value.c \

src/lib/eo/eo.c

@@ -1855,7 +1855,7 @@ eo_destructed_is(const Eo *obj_id)
 {
    EO_OBJ_POINTER_RETURN_VAL(obj_id, obj, EINA_FALSE);
 
-   return obj->del;
+   return obj->destructed;
 }
 
 EAPI void
@@ -1876,7 +1876,7 @@ eo_manual_free(Eo *obj_id)
         return EINA_FALSE;
      }
 
-   if (!obj->del)
+   if (!obj->destructed)
      {
         ERR("Tried deleting the object %p while still referenced(%d).", obj_id, obj->refcount);
         return EINA_FALSE;

src/lib/eo/eo_private.h

@@ -104,7 +104,8 @@ struct _Eo_Object
      Eina_Bool finalized:1;
 
      Eina_Bool composite:1;
-     Eina_Bool del:1;
+     Eina_Bool del_triggered:1;
+     Eina_Bool destructed:1;
      Eina_Bool manual_free:1;
 };
 
@@ -235,7 +236,7 @@ _eo_del_internal(const char *file, int line, _Eo_Object *obj)
           }
      }
 
-   obj->del = EINA_TRUE;
+   obj->destructed = EINA_TRUE;
    obj->refcount--;
 }
 
@@ -278,9 +279,16 @@ _eo_unref(_Eo_Object *obj)
    --(obj->refcount);
    if (obj->refcount == 0)
      {
-        if (obj->del)
+        if (obj->del_triggered)
           {
-             ERR("Object %p already deleted.", obj);
+             ERR("Object %p deletion already triggered. You wrongly call eo_unref() within a destructor.", obj);
+             return;
+          }
+        obj->del_triggered = EINA_TRUE;
+
+        if (obj->destructed)
+          {
+             ERR("Object %p already destructed.", obj);
              return;
           }
 

src/tests/eo/suite/eo_suite.c

@@ -20,6 +20,7 @@ static const Eo_Test_Case etc[] = {
   { "Eo init", eo_test_init },
   { "Eo general", eo_test_general },
   { "Eo class errors", eo_test_class_errors },
+  { "Eo class behaviour errors", eo_test_class_behaviour_errors },
   { "Eo call errors", eo_test_call_errors },
   { "Eo eina value", eo_test_value },
   { "Eo threaded eo calls", eo_test_threaded_calls },

src/tests/eo/suite/eo_suite.h

@@ -6,6 +6,7 @@
 void eo_test_init(TCase *tc);
 void eo_test_general(TCase *tc);
 void eo_test_class_errors(TCase *tc);
+void eo_test_class_behaviour_errors(TCase *tc);
 void eo_test_call_errors(TCase *tc);
 void eo_test_value(TCase *tc);
 void eo_test_threaded_calls(TCase *tc);

src/tests/eo/suite/eo_test_class_behaviour_errors.c

@@ -0,0 +1,63 @@
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+
+#include <stdio.h>
+
+#include "Eo.h"
+#include "eo_suite.h"
+#include "eo_error_msgs.h"
+#include "eo_test_class_simple.h"
+
+static struct log_ctx ctx;
+
+const Eo_Class *klass;
+
+static void _destructor_unref(Eo *obj, void *class_data EINA_UNUSED)
+{
+   eo_do_super(obj, klass, eo_destructor());
+
+   /* this triggers an eo stack overflow if not correctly protected */
+   eo_unref(obj);
+}
+
+START_TEST(eo_destructor_unref)
+{
+   eo_init();
+   eina_log_print_cb_set(eo_test_print_cb, &ctx);
+
+   static Eo_Op_Description op_descs [] = {
+        EO_OP_FUNC_OVERRIDE(eo_destructor, _destructor_unref),
+        EO_OP_SENTINEL
+   };
+
+   static Eo_Class_Description class_desc = {
+        EO_VERSION,
+        "Simple",
+        EO_CLASS_TYPE_REGULAR,
+        EO_CLASS_DESCRIPTION_OPS(op_descs),
+        NULL,
+        0,
+        NULL,
+        NULL
+   };
+
+   klass = eo_class_new(&class_desc, SIMPLE_CLASS, NULL);
+   fail_unless(klass);
+
+   Eo *obj = eo_add(klass, NULL);
+   fail_unless(obj);
+
+   TEST_EO_ERROR("_eo_unref", "Object %p deletion already triggered. You wrongly call eo_unref() within a destructor.");
+   eo_unref(obj);
+
+   eina_log_print_cb_set(eina_log_print_cb_stderr, NULL);
+
+   eo_shutdown();
+}
+END_TEST
+
+void eo_test_class_behaviour_errors(TCase *tc)
+{
+   tcase_add_test(tc, eo_destructor_unref);
+}