1/*
2 * Copyright (c) 2006 Kungliga Tekniska Högskolan
3 * (Royal Institute of Technology, Stockholm, Sweden).
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 *
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 *
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 *
17 * 3. Neither the name of KTH nor the names of its contributors may be
18 *    used to endorse or promote products derived from this software without
19 *    specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY KTH AND ITS CONTRIBUTORS ``AS IS'' AND ANY
22 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
24 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL KTH OR ITS CONTRIBUTORS BE
25 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
26 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
27 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
28 * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
29 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
30 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
31 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32 */
33
34#include <common.h>
35RCSID("$Id$");
36
37krb5_error_code
38store_string(krb5_storage *sp, const char *str)
39{
40    size_t len = strlen(str) + 1;
41    krb5_error_code ret;
42
43    ret = krb5_store_int32(sp, len);
44    if (ret)
45	return ret;
46    ret = krb5_storage_write(sp, str, len);
47    if (ret != len)
48	return EINVAL;
49    return 0;
50}
51
52static void
53add_list(char ****list, size_t *listlen, char **str, size_t len)
54{
55    size_t i;
56    *list = erealloc(*list, sizeof(**list) * (*listlen + 1));
57
58    (*list)[*listlen] = ecalloc(len, sizeof(**list));
59    for (i = 0; i < len; i++)
60	(*list)[*listlen][i] = str[i];
61    (*listlen)++;
62}
63
64static void
65permute(char ****list, size_t *listlen,
66	char **str, const int start, const int len)
67{
68    int i, j;
69
70#define SWAP(s,i,j) { char *t = str[i]; str[i] = str[j]; str[j] = t; }
71
72    for (i = start; i < len - 1; i++) {
73	for (j = i+1; j < len; j++) {
74	    SWAP(str,i,j);
75	    permute(list, listlen, str, i+1, len);
76	    SWAP(str,i,j);
77	}
78    }
79    add_list(list, listlen, str, len);
80}
81
82char ***
83permutate_all(struct getarg_strings *strings, size_t *size)
84{
85    char **list, ***all = NULL;
86    int i;
87
88    *size = 0;
89
90    list = ecalloc(strings->num_strings, sizeof(*list));
91    for (i = 0; i < strings->num_strings; i++)
92	list[i] = strings->strings[i];
93
94    permute(&all, size, list, 0, strings->num_strings);
95    free(list);
96    return all;
97}
98