[efi] Include installed protocol list in unknown handle names
[ipxe.git] / src / core / refcnt.c
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., 51 Franklin Street, Fifth Floor, Boston, MA
17 * 02110-1301, USA.
18 *
19 * You can also choose to distribute this program under the terms of
20 * the Unmodified Binary Distribution Licence (as given in the file
21 * COPYING.UBDL), provided that you have satisfied its requirements.
22 */
23
24 FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
25
26 #include <stdlib.h>
27 #include <ipxe/refcnt.h>
28
29 /** @file
30 *
31 * Reference counting
32 *
33 */
34
35 /**
36 * Increment reference count
37 *
38 * @v refcnt Reference counter, or NULL
39 *
40 * If @c refcnt is NULL, no action is taken.
41 */
42 void ref_increment ( struct refcnt *refcnt ) {
43
44 if ( refcnt ) {
45 refcnt->count++;
46 DBGC2 ( refcnt, "REFCNT %p incremented to %d\n",
47 refcnt, refcnt->count );
48 }
49 }
50
51 /**
52 * Decrement reference count
53 *
54 * @v refcnt Reference counter, or NULL
55 *
56 * If the reference count decreases below zero, the object's free()
57 * method will be called.
58 *
59 * If @c refcnt is NULL, no action is taken.
60 */
61 void ref_decrement ( struct refcnt *refcnt ) {
62
63 if ( ! refcnt )
64 return;
65
66 refcnt->count--;
67 DBGC2 ( refcnt, "REFCNT %p decremented to %d\n",
68 refcnt, refcnt->count );
69
70 if ( refcnt->count >= 0 )
71 return;
72
73 if ( refcnt->count < -1 ) {
74 DBGC ( refcnt, "REFCNT %p decremented too far (%d)!\n",
75 refcnt, refcnt->count );
76 /* Avoid multiple calls to free(), which typically
77 * result in memory corruption that is very hard to
78 * track down.
79 */
80 return;
81 }
82
83 if ( refcnt->free ) {
84 DBGC ( refcnt, "REFCNT %p being freed via method %p\n",
85 refcnt, refcnt->free );
86 refcnt->free ( refcnt );
87 } else {
88 DBGC ( refcnt, "REFCNT %p being freed\n", refcnt );
89 free ( refcnt );
90 }
91 }
92
93 /**
94 * Do not free reference-counted object
95 *
96 * @v refcnt Reference counter
97 *
98 * This is meant for initializing a reference counter structure in a
99 * statically allocated object.
100 */
101 void ref_no_free ( struct refcnt *refcnt __unused ) {
102 /* Do nothing */
103 }