1/* $NetBSD: prop_stack.c,v 1.2 2007/08/30 12:23:54 joerg Exp $ */
2
3/*-
4 * Copyright (c) 2007 Joerg Sonnenberger <joerg@NetBSD.org>.
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 *
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in
15 * the documentation and/or other materials provided with the
16 * distribution.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
20 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
21 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
22 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
23 * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
24 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
25 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
26 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
27 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
28 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 */
31
32#include "prop_stack.h"
33#include "prop_object_impl.h"
34
35void
36_prop_stack_init(prop_stack_t stack)
37{
38 stack->used_intern_elems = 0;
39 SLIST_INIT(&stack->extern_elems);
40}
41
42bool
43_prop_stack_push(prop_stack_t stack, prop_object_t obj, void *data1,
44 void *data2, void *data3)
45{
46 struct _prop_stack_extern_elem *eelem;
47 struct _prop_stack_intern_elem *ielem;
48
49 if (stack->used_intern_elems == PROP_STACK_INTERN_ELEMS) {
50 eelem = _PROP_MALLOC(sizeof(*eelem), M_TEMP);
51
52 if (eelem == NULL)
53 return false;
54
55 eelem->object = obj;
56 eelem->object_data[0] = data1;
57 eelem->object_data[1] = data2;
58 eelem->object_data[2] = data3;
59
60 SLIST_INSERT_HEAD(&stack->extern_elems, eelem, stack_link);
61
62 return true;
63 }
64
65 _PROP_ASSERT(stack->used_intern_elems < PROP_STACK_INTERN_ELEMS);
66 _PROP_ASSERT(SLIST_EMPTY(&stack->extern_elems));
67
68 ielem = &stack->intern_elems[stack->used_intern_elems];
69 ielem->object = obj;
70 ielem->object_data[0] = data1;
71 ielem->object_data[1] = data2;
72 ielem->object_data[2] = data3;
73
74 ++stack->used_intern_elems;
75
76 return true;
77}
78
79bool
80_prop_stack_pop(prop_stack_t stack, prop_object_t *obj, void **data1,
81 void **data2, void **data3)
82{
83 struct _prop_stack_extern_elem *eelem;
84 struct _prop_stack_intern_elem *ielem;
85
86 if (stack->used_intern_elems == 0)
87 return false;
88
89 if ((eelem = SLIST_FIRST(&stack->extern_elems)) != NULL) {
90 _PROP_ASSERT(stack->used_intern_elems == PROP_STACK_INTERN_ELEMS);
91
92 SLIST_REMOVE_HEAD(&stack->extern_elems, stack_link);
93 if (obj)
94 *obj = eelem->object;
95 if (data1)
96 *data1 = eelem->object_data[0];
97 if (data2)
98 *data2 = eelem->object_data[1];
99 if (data3)
100 *data3 = eelem->object_data[2];
101 _PROP_FREE(eelem, M_TEMP);
102 return true;
103 }
104
105 --stack->used_intern_elems;
106 ielem = &stack->intern_elems[stack->used_intern_elems];
107
108 if (obj)
109 *obj = ielem->object;
110 if (data1)
111 *data1 = ielem->object_data[0];
112 if (data2)
113 *data2 = ielem->object_data[1];
114 if (data3)
115 *data3 = ielem->object_data[2];
116
117 return true;
118}
119