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/*
* 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.
*
* You can also choose to distribute this program under the terms of
* the Unmodified Binary Distribution Licence (as given in the file
* COPYING.UBDL), provided that you have satisfied its requirements.
*/
FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
#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 */
}
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