/* $NetBSD: prop_stack.c,v 1.3 2019/05/08 02:25:50 thorpej Exp $ */

/* $NetBSD: prop_stack.c,v 1.3 2019/05/08 02:25:50 thorpej Exp $ */

/*-
* Copyright (c) 2007 Joerg Sonnenberger <[email protected]>.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/

#include "prop_object_impl.h"
#include "prop_stack.h"

void
_prop_stack_init(prop_stack_t stack)
{
stack->used_intern_elems = 0;
SLIST_INIT(&stack->extern_elems);
}

bool
_prop_stack_push(prop_stack_t stack, prop_object_t obj, void *data1,
void *data2, void *data3)
{
struct _prop_stack_extern_elem *eelem;
struct _prop_stack_intern_elem *ielem;

if (stack->used_intern_elems == PROP_STACK_INTERN_ELEMS) {
eelem = _PROP_MALLOC(sizeof(*eelem), M_TEMP);

if (eelem == NULL)
return false;

eelem->object = obj;
eelem->object_data[0] = data1;
eelem->object_data[1] = data2;
eelem->object_data[2] = data3;

SLIST_INSERT_HEAD(&stack->extern_elems, eelem, stack_link);

return true;
}

_PROP_ASSERT(stack->used_intern_elems < PROP_STACK_INTERN_ELEMS);
_PROP_ASSERT(SLIST_EMPTY(&stack->extern_elems));

ielem = &stack->intern_elems[stack->used_intern_elems];
ielem->object = obj;
ielem->object_data[0] = data1;
ielem->object_data[1] = data2;
ielem->object_data[2] = data3;

++stack->used_intern_elems;

return true;
}

bool
_prop_stack_pop(prop_stack_t stack, prop_object_t *obj, void **data1,
void **data2, void **data3)
{
struct _prop_stack_extern_elem *eelem;
struct _prop_stack_intern_elem *ielem;

if (stack->used_intern_elems == 0)
return false;

if ((eelem = SLIST_FIRST(&stack->extern_elems)) != NULL) {
_PROP_ASSERT(stack->used_intern_elems == PROP_STACK_INTERN_ELEMS);

SLIST_REMOVE_HEAD(&stack->extern_elems, stack_link);
if (obj)
*obj = eelem->object;
if (data1)
*data1 = eelem->object_data[0];
if (data2)
*data2 = eelem->object_data[1];
if (data3)
*data3 = eelem->object_data[2];
_PROP_FREE(eelem, M_TEMP);
return true;
}

--stack->used_intern_elems;
ielem = &stack->intern_elems[stack->used_intern_elems];

if (obj)
*obj = ielem->object;
if (data1)
*data1 = ielem->object_data[0];
if (data2)
*data2 = ielem->object_data[1];
if (data3)
*data3 = ielem->object_data[2];

return true;
}