[gtk/wip/otte/inspector: 2/2] contentformats: Make sure 0 elements means the array is NULL

[Benjamin Otte <otte src gnome org>]

commit 5fbc510f94e5e1c946131c02158c76dea0f5d715
Author: Benjamin Otte <otte redhat com>
Date:   Sat Dec 11 23:21:53 2021 +0100

    contentformats: Make sure 0 elements means the array is NULL
    
    Don't return arrays with 0 elements, return NULL.

 gdk/gdkcontentformats.c | 40 +++++++++++++++++++++++++++-------------
 1 file changed, 27 insertions(+), 13 deletions(-)
---
diff --git a/gdk/gdkcontentformats.c b/gdk/gdkcontentformats.c
index 0cdc51fa52..6caaa2ca82 100644
--- a/gdk/gdkcontentformats.c
+++ b/gdk/gdkcontentformats.c
@@ -718,19 +718,33 @@ gdk_content_formats_builder_to_formats (GdkContentFormatsBuilder *builder)
 
   g_return_val_if_fail (builder != NULL, NULL);
 
-  gtypes = g_new (GType, builder->n_gtypes + 1);
-  i = builder->n_gtypes;
-  gtypes[i--] = G_TYPE_INVALID;
-  /* add backwards because most important type is last in the list */
-  for (l = builder->gtypes; l; l = l->next)
-    gtypes[i--] = GPOINTER_TO_SIZE (l->data);
-
-  mime_types = g_new (const char *, builder->n_mime_types + 1);
-  i = builder->n_mime_types;
-  mime_types[i--] = NULL;
-  /* add backwards because most important type is last in the list */
-  for (l = builder->mime_types; l; l = l->next)
-    mime_types[i--] = l->data;
+  if (builder->n_gtypes > 0)
+    {
+      gtypes = g_new (GType, builder->n_gtypes + 1);
+      i = builder->n_gtypes;
+      gtypes[i--] = G_TYPE_INVALID;
+      /* add backwards because most important type is last in the list */
+      for (l = builder->gtypes; l; l = l->next)
+        gtypes[i--] = GPOINTER_TO_SIZE (l->data);
+    }
+  else
+    {
+      gtypes = NULL;
+    }
+
+  if (builder->n_mime_types > 0)
+    {
+      mime_types = g_new (const char *, builder->n_mime_types + 1);
+      i = builder->n_mime_types;
+      mime_types[i--] = NULL;
+      /* add backwards because most important type is last in the list */
+      for (l = builder->mime_types; l; l = l->next)
+        mime_types[i--] = l->data;
+    }
+  else
+    {
+      mime_types = NULL;
+    }
 
   result = gdk_content_formats_new_take (gtypes, builder->n_gtypes,
                                          mime_types, builder->n_mime_types);