Add copy and free function annotations for POD types

Plain Old Data (POD) types with or without a representation in the GType
type system can still have a copy and/or a free function. We should
allow annotating these types with their corresponding functions for
copying their data into a new instance, and freeing their data.

From a language bindings perspective, POD types should have a boxed
GType wrapper around them, so they can use the generic GBoxed API to
copy and free instances; from a documentation perspective, though, it'd
be good to have a way to match a structured type, like a struct or a
union, with its copy and free functions.

In order to do that, we add two new header block annotations:

- (copy-func function_name)
- (free-func function_name)

These annotations work exactly like ref-func and unref-func for typed
instances:

    /**
     * GdkRGBA: (copy-func gdk_rgba_copy)
     *   (free-func gdk_rgba_free)
     * @red: ...
     * @green: ...
     * @blue: ...
     * @alpha: ...
     *
     * ...
     */

The function is stored in the GIR data as two new attributes for the
`<record>` and `<union>` elements:

    <record name="RGBA"
            c:type="GdkRGBA"
            copy-function="gdk_rgba_copy"
            free-function="gdk_rgba_free"
            glib:type-name="GdkRGBA"
            glib:get-type="gdk_rgba_get_type"
            c:symbol-prefix="gdk_rgba">

The annotations are not mandatory.

See: #14

1 files changed, 8 insertions, 0 deletions

diff --git a/giscanner/girwriter.py b/giscanner/girwriter.py
index a3b3bc3e..810acad6 100644
--- a/giscanner/girwriter.py
+++ b/giscanner/girwriter.py
@@ -593,6 +593,10 @@ class GIRWriter(XMLWriter):
             is_gtype_struct = True
             attrs.append(('glib:is-gtype-struct-for',
                           self._type_to_name(record.is_gtype_struct_for)))
+        if record.copy_func:
+            attrs.append(('copy-function', record.copy_func))
+        if record.free_func:
+            attrs.append(('free-function', record.free_func))
         self._append_version(record, attrs)
         self._append_node_generic(record, attrs)
         self._append_registered(record, attrs)
@@ -621,6 +625,10 @@ class GIRWriter(XMLWriter):
         self._append_registered(union, attrs)
         if union.c_symbol_prefix:
             attrs.append(('c:symbol-prefix', union.c_symbol_prefix))
+        if union.copy_func:
+            attrs.append(('copy-function', union.copy_func))
+        if union.free_func:
+            attrs.append(('free-function', union.free_func))
         with self.tagcontext('union', attrs):
             self._write_generic(union)
             if union.fields: