Add destructors

test/test_refcount.c

@@ -32,11 +32,23 @@ void destroy_callback(void *a_raw, void *ignored) {
     counting_free(a);
 }
 
+void reref_destructor(void *a, void *ctx_raw) {
+    const RefcountContext *ctx = ctx_raw;
+    refcount_context_ref(ctx, a);
+}
+
 int main(int argc, const char **argv) {
     RefcountContext *c =
         refcount_make_context(offsetof(A, refcount), held_refs_callback,
                               destroy_callback, NULL, &COUNTING_ALLOCATOR);
 
+    A static_a = {
+        .num = 0,
+        .str = counting_strdup("static"),
+        .next = make_a(c, 0, "in static"),
+    };
+    refcount_context_init_static(c, &static_a);
+
     A *a = make_a(c, 10, "Hello world\n");
     assert(!refcount_context_is_static(c, a));
     assert(refcount_context_num_refs(c, a) == 0);
@@ -148,6 +160,20 @@ int main(int argc, const char **argv) {
     refcount_context_destroy_weakref(c, w);
     refcount_context_destroy_weakref(c, x);
 
+    a = make_a(c, 10, "test destructor");
+    assert(refcount_context_num_refs(c, a) == 0);
+    int key;
+    assert(refcount_context_add_destructor(c, a, &key, reref_destructor, c));
+    assert(refcount_context_num_refs(c, a) == 0);
+    assert(!refcount_context_unref(c, a));
+    assert(refcount_context_num_refs(c, a) == 1);
+    assert(refcount_context_remove_destructor(c, a, &key));
+    assert(refcount_context_num_refs(c, a) == 1);
+    assert(!refcount_context_unref(c, a));
+
+    refcount_context_deinit_static(c, &static_a);
+    counting_free(static_a.str);
+
     refcount_context_destroy(c);
 
     check_allocator_status();