How to make GValue automatically cleanup gchar*s

Question

I want my GValue to contain and own a dynamic string (gchar*). It should clean up the string (gchar*) on termination.

I'm trying to use a Boxed Type, but I can't get it to work.

This is what I've got so far:

GType boxedString = g_boxed_type_register_static (
                   "boxedString", boxed_copy, boxed_free);

GValue * val = g_new0(GValue, 1);
g_value_init (val, boxedString);
g_value_take_string (val, g_strdup ("hello"));

But that throws a g_value_take_string: assertion 'G_VALUE_HOLDS_STRING (value)' failed.

What I've tried and didn't work

• Use g_value_take_string: Doesn't work. String is not owned and therefore not freed.

GValue * val = g_new0(GValue, 1);
g_value_init (val, G_TYPE_STRING);
g_value_take_string (val, g_strdup ("hello"));

• Use G_TYPE_STRING: Doesn't work. String is not owned and therefore not freed.

Other options:

• If there would be a derivative of GObject, that can hold a pointer and a destruction method, it would work. But I can't find any type that allows it.

Answer 1

The string won’t be freed until you call g_value_unset().

GValue *val = g_new0 (GValue, 1);  // you can also stack-allocate it to avoid a call to g_new0()
g_value_init (val, G_TYPE_STRING);
g_value_set_string (val, "hello");
// or g_value_take_string (val, g_strdup ("hello"));

…

g_value_unset (val);
g_free (val);