diff options
author | 2015-08-28 09:58:54 +0800 | |
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committer | 2015-09-01 12:44:00 +0800 | |
commit | e44e3482bdb4d0ebde2d8b41830ac2cdb07948fb (patch) | |
tree | 66b09f592c55df2878107a468a91d21506104d3f /qemu/roms/ipxe/src/core/refcnt.c | |
parent | 9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (diff) |
Add qemu 2.4.0
Change-Id: Ic99cbad4b61f8b127b7dc74d04576c0bcbaaf4f5
Signed-off-by: Yang Zhang <yang.z.zhang@intel.com>
Diffstat (limited to 'qemu/roms/ipxe/src/core/refcnt.c')
-rw-r--r-- | qemu/roms/ipxe/src/core/refcnt.c | 99 |
1 files changed, 99 insertions, 0 deletions
diff --git a/qemu/roms/ipxe/src/core/refcnt.c b/qemu/roms/ipxe/src/core/refcnt.c new file mode 100644 index 000000000..68a86120e --- /dev/null +++ b/qemu/roms/ipxe/src/core/refcnt.c @@ -0,0 +1,99 @@ +/* + * 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., 51 Franklin Street, Fifth Floor, Boston, MA + * 02110-1301, USA. + */ + +FILE_LICENCE ( GPL2_OR_LATER ); + +#include <stdlib.h> +#include <ipxe/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_increment ( struct refcnt *refcnt ) { + + if ( refcnt ) { + refcnt->count++; + DBGC2 ( refcnt, "REFCNT %p incremented to %d\n", + refcnt, refcnt->count ); + } +} + +/** + * 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_decrement ( struct refcnt *refcnt ) { + + if ( ! refcnt ) + return; + + refcnt->count--; + DBGC2 ( refcnt, "REFCNT %p decremented to %d\n", + refcnt, refcnt->count ); + + if ( refcnt->count >= 0 ) + return; + + if ( refcnt->count < -1 ) { + DBGC ( refcnt, "REFCNT %p decremented too far (%d)!\n", + refcnt, refcnt->count ); + /* Avoid multiple calls to free(), which typically + * result in memory corruption that is very hard to + * track down. + */ + return; + } + + if ( refcnt->free ) { + DBGC ( refcnt, "REFCNT %p being freed via method %p\n", + refcnt, refcnt->free ); + refcnt->free ( refcnt ); + } else { + DBGC ( refcnt, "REFCNT %p being freed\n", refcnt ); + free ( refcnt ); + } +} + +/** + * Do not free reference-counted object + * + * @v refcnt Reference counter + * + * This is meant for initializing a reference counter structure in a + * statically allocated object. + */ +void ref_no_free ( struct refcnt *refcnt __unused ) { + /* Do nothing */ +} |