1 /*
2 * Copyright (C) 2007 Michael Brown <mbrown@fensystems.co.uk>.
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License as
6 * published by the Free Software Foundation; either version 2 of the
7 * License, or any later version.
8 *
9 * This program is distributed in the hope that it will be useful, but
10 * WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
17 */
18
19 FILE_LICENCE ( GPL2_OR_LATER );
20
21 #include <gpxe/interface.h>
22
23 /** @file
24 *
25 * Object communication interfaces
26 *
27 */
28
29 /**
30 * Plug an interface into a new destination interface
31 *
32 * @v intf Interface
33 * @v dest New destination interface
34 *
35 * The reference to the existing destination interface is dropped, a
36 * reference to the new destination interface is obtained, and the
37 * interface is updated to point to the new destination interface.
38 *
39 * Note that there is no "unplug" call; instead you must plug the
40 * interface into a null interface.
41 */
plug(struct interface * intf,struct interface * dest)42 void plug ( struct interface *intf, struct interface *dest ) {
43 DBGC ( intf, "INTF %p moving from INTF %p to INTF %p\n",
44 intf, intf->dest, dest );
45 intf_put ( intf->dest );
46 intf->dest = intf_get ( dest );
47 }
48
49 /**
50 * Plug two interfaces together
51 *
52 * @v a Interface A
53 * @v b Interface B
54 *
55 * Plugs interface A into interface B, and interface B into interface
56 * A. (The basic plug() function is unidirectional; this function is
57 * merely a shorthand for two calls to plug(), hence the name.)
58 */
plug_plug(struct interface * a,struct interface * b)59 void plug_plug ( struct interface *a, struct interface *b ) {
60 plug ( a, b );
61 plug ( b, a );
62 }
63