/usr.bin/csup/attrstack.c

 1/*-
 2 * Copyright (c) 2006, Maxime Henrion <mux@FreeBSD.org>
 3 * All rights reserved.
 4 *
 5 * Redistribution and use in source and binary forms, with or without
 6 * modification, are permitted provided that the following conditions
 7 * are met:
 8 * 1. Redistributions of source code must retain the above copyright
 9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 *
26 * $Id$
27 */
28
29#include <assert.h>
30#include <stdlib.h>
31
32#include "attrstack.h"
33#include "fattr.h"
34#include "misc.h"
35
36#define	ATTRSTACK_DEFSIZE	16	/* Initial size of the stack. */
37
38struct attrstack {
39	struct fattr **stack;
40	size_t cur;
41	size_t size;
42};
43
44struct attrstack *
45attrstack_new(void)
46{
47	struct attrstack *as;
48
49	as = xmalloc(sizeof(struct attrstack));
50	as->stack = xmalloc(sizeof(struct fattr *) * ATTRSTACK_DEFSIZE);
51	as->size = ATTRSTACK_DEFSIZE;
52	as->cur = 0;
53	return (as);
54}
55
56struct fattr *
57attrstack_pop(struct attrstack *as)
58{
59
60	assert(as->cur > 0);
61	return (as->stack[--as->cur]);
62}
63
64void
65attrstack_push(struct attrstack *as, struct fattr *fa)
66{
67
68	if (as->cur >= as->size) {
69		as->size *= 2;
70		as->stack = xrealloc(as->stack,
71		    sizeof(struct fattr *) * as->size);
72	}
73	as->stack[as->cur++] = fa;
74}
75
76size_t
77attrstack_size(struct attrstack *as)
78{
79
80	return (as->cur);
81}
82
83void
84attrstack_free(struct attrstack *as)
85{
86
87	assert(as->cur == 0);
88	free(as->stack);
89	free(as);
90}