1/*	$NetBSD: catgets.c,v 1.17 2005/11/29 03:12:00 christos Exp $	*/
2
3/*-
4 * Copyright (c) 1996 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by J.T. Conklin.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 *    notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in the
17 *    documentation and/or other materials provided with the distribution.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 * POSSIBILITY OF SUCH DAMAGE.
30 */
31
32#include <sys/cdefs.h>
33#if defined(LIBC_SCCS) && !defined(lint)
34__RCSID("$NetBSD: catgets.c,v 1.17 2005/11/29 03:12:00 christos Exp $");
35#endif /* LIBC_SCCS and not lint */
36
37#define _NLS_PRIVATE
38
39#include "namespace.h"
40#include <errno.h>
41#include <stdlib.h>
42#include <string.h>
43#include <nl_types.h>
44
45#ifdef __weak_alias
46__weak_alias(catgets, _catgets)
47#endif
48
49char *
50_catgets(catd, set_id, msg_id, s)
51	nl_catd catd;
52	int set_id;
53	int msg_id;
54	const char *s;
55{
56	struct _nls_cat_hdr *cat_hdr;
57	struct _nls_set_hdr *set_hdr;
58	struct _nls_msg_hdr *msg_hdr;
59	int l, u, i, r;
60
61	if (catd == (nl_catd) -1) {
62		errno = EBADF;
63		return __UNCONST(s);
64	}
65
66	cat_hdr = (struct _nls_cat_hdr *)catd->__data;
67	set_hdr = (struct _nls_set_hdr *)(void *)((char *)catd->__data
68		+ sizeof(struct _nls_cat_hdr));
69
70	/* binary search, see knuth algorithm b */
71	l = 0;
72	u = ntohl((u_int32_t)cat_hdr->__nsets) - 1;
73	while (l <= u) {
74		i = (l + u) / 2;
75		r = set_id - ntohl((u_int32_t)set_hdr[i].__setno);
76
77		if (r == 0) {
78			msg_hdr = (struct _nls_msg_hdr *)
79			    (void *)((char *)catd->__data +
80			    sizeof(struct _nls_cat_hdr) +
81			    ntohl((u_int32_t)cat_hdr->__msg_hdr_offset));
82
83			l = ntohl((u_int32_t)set_hdr[i].__index);
84			u = l + ntohl((u_int32_t)set_hdr[i].__nmsgs) - 1;
85			while (l <= u) {
86				i = (l + u) / 2;
87				r = msg_id -
88				    ntohl((u_int32_t)msg_hdr[i].__msgno);
89				if (r == 0) {
90					return ((char *) catd->__data +
91					    sizeof(struct _nls_cat_hdr) +
92					    ntohl((u_int32_t)
93					    cat_hdr->__msg_txt_offset) +
94					    ntohl((u_int32_t)
95					    msg_hdr[i].__offset));
96				} else if (r < 0) {
97					u = i - 1;
98				} else {
99					l = i + 1;
100				}
101			}
102
103			/* not found */
104			goto notfound;
105
106		} else if (r < 0) {
107			u = i - 1;
108		} else {
109			l = i + 1;
110		}
111	}
112
113notfound:
114	/* not found */
115	errno = ENOMSG;
116	return __UNCONST(s);
117}
118