diff options
author | Michael Brown | 2007-04-30 01:53:39 +0200 |
---|---|---|
committer | Michael Brown | 2007-04-30 01:53:39 +0200 |
commit | d40761d7258cd509d698c210fc6c478bd7788c6b (patch) | |
tree | c7f419e1e189936d706a53c26fc9f236e0118b6d /src/core/refcnt.c | |
parent | Skeleton job control interface (diff) | |
download | ipxe-d40761d7258cd509d698c210fc6c478bd7788c6b.tar.gz ipxe-d40761d7258cd509d698c210fc6c478bd7788c6b.tar.xz ipxe-d40761d7258cd509d698c210fc6c478bd7788c6b.zip |
Add (and use) generic reference counter, to improve signal:noise ratio
in code defining reference-counted objects.
Diffstat (limited to 'src/core/refcnt.c')
-rw-r--r-- | src/core/refcnt.c | 73 |
1 files changed, 73 insertions, 0 deletions
diff --git a/src/core/refcnt.c b/src/core/refcnt.c new file mode 100644 index 00000000..4efd9d71 --- /dev/null +++ b/src/core/refcnt.c @@ -0,0 +1,73 @@ +/* + * Copyright (C) 2007 Michael Brown <mbrown@fensystems.co.uk>. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation; either version 2 of the + * License, or any later version. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + */ + +#include <stdlib.h> +#include <gpxe/refcnt.h> + +/** @file + * + * Reference counting + * + */ + +/** + * Increment reference count + * + * @v refcnt Reference counter, or NULL + * + * If @c refcnt is NULL, no action is taken. + */ +void ref_get ( struct refcnt *refcnt ) { + + if ( ! refcnt ) + return; + + refcnt->refcnt++; + + DBGC ( refcnt, "REFCNT %p incremented to %d\n", + refcnt, refcnt->refcnt ); +} + +/** + * Decrement reference count + * + * @v refcnt Reference counter, or NULL + * + * If the reference count decreases below zero, the object's free() + * method will be called. + * + * If @c refcnt is NULL, no action is taken. + */ +void ref_put ( struct refcnt *refcnt ) { + + if ( ! refcnt ) + return; + + refcnt->refcnt--; + DBGC ( refcnt, "REFCNT %p decremented to %d\n", + refcnt, refcnt->refcnt ); + + if ( refcnt->refcnt >= 0 ) + return; + + if ( refcnt->free ) { + refcnt->free ( refcnt ); + } else { + free ( refcnt ); + } +} |