xref: /netbsd/lib/libc/nls/catgets.c (revision bf9ec67e)
1 /*	$NetBSD: catgets.c,v 1.15 1999/08/17 04:00:51 mycroft 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  * 3. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *        This product includes software developed by the NetBSD
21  *        Foundation, Inc. and its contributors.
22  * 4. Neither the name of The NetBSD Foundation nor the names of its
23  *    contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
27  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
28  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
29  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
30  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
33  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
34  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36  * POSSIBILITY OF SUCH DAMAGE.
37  */
38 
39 #define _NLS_PRIVATE
40 
41 #include "namespace.h"
42 #include <errno.h>
43 #include <stdlib.h>
44 #include <string.h>
45 #include <nl_types.h>
46 
47 #ifdef __weak_alias
48 __weak_alias(catgets, _catgets)
49 #endif
50 
51 char *
52 _catgets(catd, set_id, msg_id, s)
53 	nl_catd catd;
54 	int set_id;
55 	int msg_id;
56 	const char *s;
57 {
58 	struct _nls_cat_hdr *cat_hdr;
59 	struct _nls_set_hdr *set_hdr;
60 	struct _nls_msg_hdr *msg_hdr;
61 	int l, u, i, r;
62 
63 	if (catd == (nl_catd) -1) {
64 		errno = EBADF;
65 		/* LINTED interface problem */
66 		return (char *) s;
67 	}
68 
69 	cat_hdr = (struct _nls_cat_hdr *)catd->__data;
70 	set_hdr = (struct _nls_set_hdr *)(void *)((char *)catd->__data
71 		+ sizeof(struct _nls_cat_hdr));
72 
73 	/* binary search, see knuth algorithm b */
74 	l = 0;
75 	u = ntohl((u_int32_t)cat_hdr->__nsets) - 1;
76 	while (l <= u) {
77 		i = (l + u) / 2;
78 		r = set_id - ntohl((u_int32_t)set_hdr[i].__setno);
79 
80 		if (r == 0) {
81 			msg_hdr = (struct _nls_msg_hdr *)
82 			    (void *)((char *)catd->__data +
83 			    sizeof(struct _nls_cat_hdr) +
84 			    ntohl((u_int32_t)cat_hdr->__msg_hdr_offset));
85 
86 			l = ntohl((u_int32_t)set_hdr[i].__index);
87 			u = l + ntohl((u_int32_t)set_hdr[i].__nmsgs) - 1;
88 			while (l <= u) {
89 				i = (l + u) / 2;
90 				r = msg_id -
91 				    ntohl((u_int32_t)msg_hdr[i].__msgno);
92 				if (r == 0) {
93 					return ((char *) catd->__data +
94 					    sizeof(struct _nls_cat_hdr) +
95 					    ntohl((u_int32_t)
96 					    cat_hdr->__msg_txt_offset) +
97 					    ntohl((u_int32_t)
98 					    msg_hdr[i].__offset));
99 				} else if (r < 0) {
100 					u = i - 1;
101 				} else {
102 					l = i + 1;
103 				}
104 			}
105 
106 			/* not found */
107 			goto notfound;
108 
109 		} else if (r < 0) {
110 			u = i - 1;
111 		} else {
112 			l = i + 1;
113 		}
114 	}
115 
116 notfound:
117 	/* not found */
118 	errno = ENOMSG;
119 	/* LINTED interface problem */
120 	return (char *) s;
121 }
122