ruby: new notmuch_rb_object_destroy() helper

The struct used to store the types (rb_data_type_t) contains a "data"
field where we can store whatever we want. I use that field to store a
pointer to the corresponding destroy function. For example
notmuch_rb_database_type contains a pointer to notmuch_database_destroy.

I cast that pointer as a notmuch_status_t (func*)(void *) and call
that function passing the internal object (e.g. notmuch_database_t).

Using the rb_data_type_t data we can call the correct notmuch destroy
function.

Therefore this:

  ret = ((notmuch_status_t (*)(void *)) type->data) (nm_object);

Is effectively the same as this:

  ret = notmuch_database_destroy (database);

The advantage of doing it this way is that much less code is necesary
since each rb_data_type_t has the corresponding destroy function stored
in it.

Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>

1 files changed, 15 insertions, 0 deletions

diff --git a/bindings/ruby/defs.h b/bindings/ruby/defs.h
index fa7b9515..9860ee17 100644
--- a/bindings/ruby/defs.h
+++ b/bindings/ruby/defs.h
@@ -105,6 +105,21 @@ extern const rb_data_type_t notmuch_rb_tags_type;
 #define Data_Get_Notmuch_Tags(obj, ptr) \
     Data_Get_Notmuch_Object ((obj), &notmuch_rb_tags_type, (ptr))
 
+static inline notmuch_status_t
+notmuch_rb_object_destroy (VALUE rb_object, const rb_data_type_t *type)
+{
+    void *nm_object;
+    notmuch_status_t ret;
+
+    Data_Get_Notmuch_Object (rb_object, type, nm_object);
+
+    /* Call the corresponding notmuch_*_destroy function */
+    ret = ((notmuch_status_t (*)(void *)) type->data) (nm_object);
+    DATA_PTR (rb_object) = NULL;
+
+    return ret;
+}
+
 /* status.c */
 void
 notmuch_rb_status_raise (notmuch_status_t status);