glib/gbytes: Be more careful when saving a GBytes of NULL

In 1e3b010 the behaviour of `g_bytes_new (NULL, 0)` was changed; before the `g_bytes_get_data()` would return NULL as expected, but now it returns a pointer outside the single GBytes allocation. This breaks the fwupd self tests as we use a GBytes of NULL to signify that the emulation data exists, but it has no content. Catch this case and restore the old behaviour.
MartinDomig · Nov 20, 2024 · 9ddc973 · 9ddc973
1 parent 3e87611
commit 9ddc973
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diff --git a/glib/gbytes.c b/glib/gbytes.c
@@ -128,7 +128,7 @@ g_bytes_new (gconstpointer data,
       GBytesInline *bytes;
 
       bytes = g_malloc (sizeof *bytes + size);
-      bytes->bytes.data = bytes->inline_data;
+      bytes->bytes.data = data != NULL ? bytes->inline_data : NULL;
       bytes->bytes.size = size;
       bytes->bytes.free_func = NULL;
       bytes->bytes.user_data = NULL;

diff --git a/glib/tests/bytes.c b/glib/tests/bytes.c
@@ -451,6 +451,7 @@ test_null (void)
   gsize size;
 
   bytes = g_bytes_new (NULL, 0);
+  g_assert_null (g_bytes_get_data (bytes, NULL));
 
   data = g_bytes_unref_to_data (bytes, &size);