1 /* 2 * Copyright (C) 2007 Michael Brown <mbrown (at) 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 */ 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 */ 59 void plug_plug ( struct interface *a, struct interface *b ) { 60 plug ( a, b ); 61 plug ( b, a ); 62 } 63