xref: /illumos-gate/usr/src/lib/libc/port/locale/setlocale.c (revision a6bde1a23b60f140c7ed78df979c2e22b1ed9b2c)
1 /*
2  * Copyright 2014 Garrett D'Amore <garrett@damore.org>
3  * Copyright 2010 Nexenta Systems, Inc.  All rights reserved.
4  * Copyright (c) 1996 - 2002 FreeBSD Project
5  * Copyright (c) 1991, 1993
6  *	The Regents of the University of California.  All rights reserved.
7  *
8  * This code is derived from software contributed to Berkeley by
9  * Paul Borman at Krystal Technologies.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  * 4. Neither the name of the University nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 
36 #include "lint.h"
37 #include <sys/types.h>
38 #include <sys/stat.h>
39 #include <errno.h>
40 #include <limits.h>
41 #include <locale.h>
42 #include <stdlib.h>
43 #include <string.h>
44 #include <unistd.h>
45 #include <stdio.h>
46 #include "mtlib.h"
47 #include "collate.h"
48 #include "lnumeric.h"	/* for struct lc_numeric */
49 #include "lctype.h"	/* for struct lc_ctype */
50 #include "setlocale.h"
51 #include "../i18n/_loc_path.h"
52 #include "localeimpl.h"
53 #include "../i18n/_locale.h"
54 
55 /*
56  * Path to locale storage directory.  See ../i18n/_loc_path.h
57  */
58 char	*_PathLocale = _DFLT_LOC_PATH;
59 
60 static char	*current_locale(locale_t, int);
61 static void	install_legacy(locale_t, int);
62 
63 static mutex_t setlocale_lock = DEFAULTMUTEX;
64 static locale_t setlocale_list = NULL;
65 
66 char *
67 setlocale(int category, const char *locname)
68 {
69 	locale_t loc;
70 	locale_t srch;
71 	int mask;
72 
73 	if (category < 0 || category > LC_ALL) {
74 		errno = EINVAL;
75 		return (NULL);
76 	}
77 
78 	if (locname == NULL)
79 		return (current_locale(___global_locale, category));
80 
81 	mask = (category == LC_ALL ? LC_ALL_MASK : (1 << category));
82 
83 	loc = newlocale(mask, locname, NULL);
84 	if (loc == NULL) {
85 		return (NULL);
86 	}
87 
88 	/*
89 	 * This next logic looks to see if we have ever used the same locale
90 	 * settings before.  If so, we reuse it.  We avoid ever calling
91 	 * freelocale() on a locale setting built up by setlocale, this
92 	 * ensures that consumers (uselocale) will always be thread safe;
93 	 * the actual locale data objects are never freed, and unique
94 	 * locale objects are also never freed.  We reuse to avoid leaking
95 	 * memory in applications that call setlocale repeatedly.
96 	 */
97 	lmutex_lock(&setlocale_lock);
98 	for (srch = setlocale_list; srch != NULL; srch = srch->next) {
99 		if (strcmp(srch->locname, loc->locname) == 0) {
100 			break;
101 		}
102 	}
103 
104 	if (srch == NULL) {
105 		/* this is a new locale, save it for reuse later */
106 		loc->next = setlocale_list;
107 		loc->on_list = 1;
108 		setlocale_list = loc;
109 	} else {
110 		/* we already had it, toss the new, and use what we found */
111 		freelocale(loc);
112 		loc = srch;
113 	}
114 	___global_locale = loc;
115 
116 	install_legacy(loc, mask);
117 	lmutex_unlock(&setlocale_lock);
118 
119 	return (current_locale(loc, category));
120 }
121 
122 static char *
123 current_locale(locale_t loc, int cat)
124 {
125 	switch (cat) {
126 	case LC_CTYPE:
127 	case LC_COLLATE:
128 	case LC_MESSAGES:
129 	case LC_MONETARY:
130 	case LC_NUMERIC:
131 	case LC_TIME:
132 		return (loc->locdata[cat]->l_lname);
133 	case LC_ALL:
134 		return (loc->locname);
135 	default:
136 		return (NULL);
137 	}
138 }
139 
140 static void
141 install_legacy(locale_t loc, int mask)
142 {
143 	/*
144 	 * Update the legacy fixed variables that may be baked into
145 	 * legacy programs.  This is really unfortunate, but we can't
146 	 * solve for them otherwise.  Note that such legacy programs
147 	 * are only going to see the global locale settings, and cannot
148 	 * benefit from uselocale().
149 	 */
150 	if (mask & LC_NUMERIC_MASK) {
151 		struct lc_numeric *lnum;
152 		lnum = loc->locdata[LC_NUMERIC]->l_data[0];
153 		_numeric[0] = *lnum->decimal_point;
154 		_numeric[1] = *lnum->thousands_sep;
155 	}
156 
157 	if (mask & LC_CTYPE_MASK) {
158 		struct lc_ctype *lct;
159 		lct = loc->locdata[LC_CTYPE]->l_data[0];
160 		for (int i = 0; i < _CACHED_RUNES; i++) {
161 			/* ctype can only encode the lower 8 bits. */
162 			__ctype[i+1] = lct->lc_ctype_mask[i] & 0xff;
163 			__ctype_mask[i] = lct->lc_ctype_mask[i];
164 		}
165 
166 		/* The bottom half is the toupper/lower array */
167 		for (int i = 0; i < _CACHED_RUNES; i++) {
168 			int u, l;
169 			__ctype[258 + i] = i;
170 			u = lct->lc_trans_upper[i];
171 			l = lct->lc_trans_lower[i];
172 			if (u && u != i)
173 				__ctype[258+i] = u;
174 			if (l && l != i)
175 				__ctype[258+i] = l;
176 
177 			/* Don't forget these annoyances either! */
178 			__trans_upper[i] = u;
179 			__trans_lower[i] = l;
180 		}
181 
182 		/* Maximum mblen, cswidth, weird legacy */
183 		__ctype[520] = lct->lc_max_mblen;
184 	}
185 }
186