1/*	$OpenBSD: catgets.c,v 1.9 2015/09/05 11:25:30 guenther Exp $ */
2/*-
3 * Copyright (c) 1996 The NetBSD Foundation, Inc.
4 * All rights reserved.
5 *
6 * This code is derived from software contributed to The NetBSD Foundation
7 * by J.T. Conklin.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 *    notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 *    notice, this list of conditions and the following disclaimer in the
16 *    documentation and/or other materials provided with the distribution.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
19 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
20 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
21 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE
22 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
23 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
24 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
25 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
26 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
27 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
28 * POSSIBILITY OF SUCH DAMAGE.
29 */
30
31#define _NLS_PRIVATE
32
33#include <errno.h>
34#include <stdlib.h>
35#include <string.h>
36#include <nl_types.h>
37
38char *
39catgets(nl_catd catd, int set_id, int msg_id, const char *s)
40{
41	struct _nls_cat_hdr *cat_hdr;
42	struct _nls_set_hdr *set_hdr;
43	struct _nls_msg_hdr *msg_hdr;
44	int l, u, i, r;
45
46	if (catd == (nl_catd) -1) {
47		errno = EBADF;
48		return (char *) s;
49	}
50
51	cat_hdr = (struct _nls_cat_hdr *) catd->__data;
52	set_hdr = (struct _nls_set_hdr *) ((char *)catd->__data
53		+ sizeof(struct _nls_cat_hdr));
54
55	/* binary search, see knuth algorithm b */
56	l = 0;
57	u = ntohl(cat_hdr->__nsets) - 1;
58	while (l <= u) {
59		i = (l + u) / 2;
60		r = set_id - ntohl(set_hdr[i].__setno);
61
62		if (r == 0) {
63			msg_hdr = (struct _nls_msg_hdr *) ((char *)catd->__data
64				+ sizeof(struct _nls_cat_hdr)
65				+ ntohl(cat_hdr->__msg_hdr_offset));
66
67			l = ntohl(set_hdr[i].__index);
68			u = l + ntohl(set_hdr[i].__nmsgs) - 1;
69			while (l <= u) {
70				i = (l + u) / 2;
71				r = msg_id - ntohl(msg_hdr[i].__msgno);
72				if (r == 0) {
73					return (char *) catd->__data
74					    + sizeof(struct _nls_cat_hdr)
75					    + ntohl(cat_hdr->__msg_txt_offset)
76					    + ntohl(msg_hdr[i].__offset);
77				} else if (r < 0) {
78					u = i - 1;
79				} else {
80					l = i + 1;
81				}
82			}
83
84			/* not found */
85			return (char *) s;
86
87		} else if (r < 0) {
88			u = i - 1;
89		} else {
90			l = i + 1;
91		}
92	}
93
94	/* not found */
95	return (char *) s;
96}
97DEF_WEAK(catgets);
98