Bug 557383 - Virtual method support

Broadly speaking, this change adds the concept of <vfunc> to the .gir.
The typelib already had most of the infrastructure for virtual functions,
though there is one API addition.

The scanner assumes that any class callback slot that doesn't match
a signal name is a virtual.  In the .gir, we write out *both* the <method>
wrapper and a <vfunc>.  If we can determine an association between
them (based on the names matching, or a new Virtual: annotation),
then we notate that in the .gir.

The typelib gains an association from the vfunc to the function, if
it exists.  This will be useful for bindings since they already know
how to consume FunctionInfo.

1 files changed, 116 insertions, 0 deletions

diff --git a/girepository/ginfo.c b/girepository/ginfo.c
index fcc5f09..d522a56 100644
--- a/girepository/ginfo.c
+++ b/girepository/ginfo.c
@@ -1527,6 +1527,63 @@ g_object_info_get_vfunc (GIObjectInfo *info,
 				     base->typelib, offset);  
 }
 
+static GIVFuncInfo *
+find_vfunc (GIBaseInfo   *base,
+            guint32       offset,
+            gint          n_vfuncs,
+            const gchar  *name)
+{
+  /* FIXME hash */
+  Header *header = (Header *)base->typelib->data;
+  gint i;
+
+  for (i = 0; i < n_vfuncs; i++)
+    {
+      VFuncBlob *fblob = (VFuncBlob *)&base->typelib->data[offset];
+      const gchar *fname = (const gchar *)&base->typelib->data[fblob->name];
+
+      if (strcmp (name, fname) == 0)
+        return (GIVFuncInfo *) g_info_new (GI_INFO_TYPE_VFUNC, base,
+                                           base->typelib, offset);
+
+      offset += header->vfunc_blob_size;
+    }
+
+  return NULL;
+}
+
+/**
+ * g_object_info_find_vfunc:
+ * @info: An #GIObjectInfo
+ * @name: The name of a virtual function to find.
+ *
+ * Locate a virtual function slot with name @name.  Note that the namespace
+ * for virtuals is distinct from that of methods; there may or may not be
+ * a concrete method associated for a virtual.  If there is one, it may
+ * be retrieved using #g_vfunc_info_get_invoker.  See the documentation for
+ * that function for more information on invoking virtuals.
+ *
+ * Return value: (transfer full): A #GIVFuncInfo, or %NULL if none with name @name.
+ */
+GIVFuncInfo *
+g_object_info_find_vfunc (GIObjectInfo *info,
+                          const gchar  *name)
+{
+  gint offset;
+  GIBaseInfo *base = (GIBaseInfo *)info;
+  Header *header = (Header *)base->typelib->data;
+  ObjectBlob *blob = (ObjectBlob *)&base->typelib->data[base->offset];
+
+  offset = base->offset + header->object_blob_size
+    + (blob->n_interfaces + blob->n_interfaces % 2) * 2
+    + blob->n_fields * header->field_blob_size
+    + blob->n_properties * header->property_blob_size
+    + blob->n_methods * header->function_blob_size
+    + blob->n_signals * header->signal_blob_size;
+
+  return find_vfunc (base, offset, blob->n_vfuncs, name);
+}
+
 gint
 g_object_info_get_n_constants (GIObjectInfo *info)
 {
@@ -1728,6 +1785,34 @@ g_interface_info_get_vfunc (GIInterfaceInfo *info,
 				     base->typelib, offset);  
 }
 
+/**
+ * g_interface_info_find_vfunc:
+ * @info: An #GIObjectInfo
+ * @name: The name of a virtual function to find.
+ *
+ * Locate a virtual function slot with name @name.  See the documentation
+ * for #g_object_info_find_vfunc for more information on virtuals.
+ *
+ * Return value: (transfer full): A #GIVFuncInfo, or %NULL if none with name @name.
+ */
+GIVFuncInfo *
+g_interface_info_find_vfunc (GIInterfaceInfo *info,
+                             const gchar  *name)
+{
+  gint offset;
+  GIBaseInfo *base = (GIBaseInfo *)info;
+  Header *header = (Header *)base->typelib->data;
+  InterfaceBlob *blob = (InterfaceBlob *)&base->typelib->data[base->offset];
+
+  offset = base->offset + header->interface_blob_size
+    + (blob->n_prerequisites + blob->n_prerequisites % 2) * 2
+    + blob->n_properties * header->property_blob_size
+    + blob->n_methods * header->function_blob_size
+    + blob->n_signals * header->signal_blob_size;
+
+  return find_vfunc (base, offset, blob->n_vfuncs, name);
+}
+
 gint
 g_interface_info_get_n_constants (GIInterfaceInfo *info)
 {
@@ -1913,6 +1998,37 @@ g_vfunc_info_get_signal (GIVFuncInfo *info)
   return NULL;
 }
 
+/**
+ * g_vfunc_info_get_invoker:
+ * @info: A #GIVFuncInfo
+ *
+ * If this virtual function has an associated invoker method, this
+ * method will return it.  An invoker method is a C entry point.
+ *
+ * Not all virtuals will have invokers.
+ *
+ * Return value: (transfer full): An invoker function, or %NULL if none known
+ */
+GIFunctionInfo *
+g_vfunc_info_get_invoker (GIVFuncInfo *info)
+{
+  GIBaseInfo *base = (GIBaseInfo *)info;
+  VFuncBlob *blob = (VFuncBlob *)&base->typelib->data[base->offset];
+  GIBaseInfo *container = base->container;
+  GIInfoType parent_type;
+
+  /* 1023 = 0x3ff is the maximum of the 10 bits for invoker index */
+  if (blob->invoker == 1023)
+    return NULL;
+
+  parent_type = g_base_info_get_type (container);
+  if (parent_type == GI_INFO_TYPE_OBJECT)
+    return g_object_info_get_method ((GIObjectInfo*)container, blob->invoker);
+  else if (parent_type == GI_INFO_TYPE_INTERFACE)
+    return g_interface_info_get_method ((GIInterfaceInfo*)container, blob->invoker);
+  else
+    g_assert_not_reached ();
+}
 
 /* GIConstantInfo functions */
 GITypeInfo *