lib/remote: Store name of remote providing keyring for dynamic remotes

When pulling from a dynamic (peer to peer) remote, the remote’s name is
set to a unique, generated string which doesn’t exist in repo/config. If
doing a non-mirror pull, however, we don’t want to use this name in the
refspecs for newly created or updated refs — we want to use the name of
the remote which provided the keyring for the pull (this will be a
remote from repo/config whose collection ID matches that being used for
the peer to peer pull).

Store both names in OstreeRemote. The name to use for refspecs is stored
as refspec_name, and is typically NULL unless it differs from name.

Signed-off-by: Philip Withnall <withnall@endlessm.com>

Closes: #1202
Approved by: cgwalters

src/libostree/ostree-remote.c

@@ -53,16 +53,25 @@
 
 OstreeRemote *
 ostree_remote_new (const gchar *name)
+{
+  return ostree_remote_new_dynamic (name, NULL);
+}
+
+OstreeRemote *
+ostree_remote_new_dynamic (const gchar *name,
+                           const gchar *refspec_name)
 {
   OstreeRemote *remote;
 
   g_return_val_if_fail (name != NULL && *name != '\0', NULL);
+  g_return_val_if_fail (refspec_name == NULL || *refspec_name != '\0', NULL);
 
   remote = g_slice_new0 (OstreeRemote);
   remote->ref_count = 1;
   remote->name = g_strdup (name);
-  remote->group = g_strdup_printf ("remote \"%s\"", name);
-  remote->keyring = g_strdup_printf ("%s.trustedkeys.gpg", name);
+  remote->refspec_name = g_strdup (refspec_name);
+  remote->group = g_strdup_printf ("remote \"%s\"", (refspec_name != NULL) ? refspec_name : name);
+  remote->keyring = g_strdup_printf ("%s.trustedkeys.gpg", (refspec_name != NULL) ? refspec_name : name);
   remote->options = g_key_file_new ();
 
   return remote;