xref: /netbsd-src/lib/libc/nls/catgets.c (revision e5548b402ae4c44fb816de42c7bba9581ce23ef5)
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  * 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 #include <sys/cdefs.h>
40 #if defined(LIBC_SCCS) && !defined(lint)
41 __RCSID("$NetBSD: catgets.c,v 1.17 2005/11/29 03:12:00 christos Exp $");
42 #endif /* LIBC_SCCS and not lint */
43 
44 #define _NLS_PRIVATE
45 
46 #include "namespace.h"
47 #include <errno.h>
48 #include <stdlib.h>
49 #include <string.h>
50 #include <nl_types.h>
51 
52 #ifdef __weak_alias
53 __weak_alias(catgets, _catgets)
54 #endif
55 
56 char *
57 _catgets(catd, set_id, msg_id, s)
58 	nl_catd catd;
59 	int set_id;
60 	int msg_id;
61 	const char *s;
62 {
63 	struct _nls_cat_hdr *cat_hdr;
64 	struct _nls_set_hdr *set_hdr;
65 	struct _nls_msg_hdr *msg_hdr;
66 	int l, u, i, r;
67 
68 	if (catd == (nl_catd) -1) {
69 		errno = EBADF;
70 		return __UNCONST(s);
71 	}
72 
73 	cat_hdr = (struct _nls_cat_hdr *)catd->__data;
74 	set_hdr = (struct _nls_set_hdr *)(void *)((char *)catd->__data
75 		+ sizeof(struct _nls_cat_hdr));
76 
77 	/* binary search, see knuth algorithm b */
78 	l = 0;
79 	u = ntohl((u_int32_t)cat_hdr->__nsets) - 1;
80 	while (l <= u) {
81 		i = (l + u) / 2;
82 		r = set_id - ntohl((u_int32_t)set_hdr[i].__setno);
83 
84 		if (r == 0) {
85 			msg_hdr = (struct _nls_msg_hdr *)
86 			    (void *)((char *)catd->__data +
87 			    sizeof(struct _nls_cat_hdr) +
88 			    ntohl((u_int32_t)cat_hdr->__msg_hdr_offset));
89 
90 			l = ntohl((u_int32_t)set_hdr[i].__index);
91 			u = l + ntohl((u_int32_t)set_hdr[i].__nmsgs) - 1;
92 			while (l <= u) {
93 				i = (l + u) / 2;
94 				r = msg_id -
95 				    ntohl((u_int32_t)msg_hdr[i].__msgno);
96 				if (r == 0) {
97 					return ((char *) catd->__data +
98 					    sizeof(struct _nls_cat_hdr) +
99 					    ntohl((u_int32_t)
100 					    cat_hdr->__msg_txt_offset) +
101 					    ntohl((u_int32_t)
102 					    msg_hdr[i].__offset));
103 				} else if (r < 0) {
104 					u = i - 1;
105 				} else {
106 					l = i + 1;
107 				}
108 			}
109 
110 			/* not found */
111 			goto notfound;
112 
113 		} else if (r < 0) {
114 			u = i - 1;
115 		} else {
116 			l = i + 1;
117 		}
118 	}
119 
120 notfound:
121 	/* not found */
122 	errno = ENOMSG;
123 	return __UNCONST(s);
124 }
125