xref: /freebsd/lib/libc/locale/xlocale.c (revision 410556f1f10fd35b350102725fd8504c3cb0afc8)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2011 The FreeBSD Foundation
5  * All rights reserved.
6  *
7  * This software was developed by David Chisnall under sponsorship from
8  * the FreeBSD Foundation.
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 AUTHOR AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  *
31  * $FreeBSD$
32  */
33 
34 #include <pthread.h>
35 #include <stdio.h>
36 #include <string.h>
37 #include <runetype.h>
38 #include "libc_private.h"
39 #include "xlocale_private.h"
40 
41 /**
42  * Each locale loader declares a global component.  This is used by setlocale()
43  * and also by xlocale with LC_GLOBAL_LOCALE..
44  */
45 extern struct xlocale_component __xlocale_global_collate;
46 extern struct xlocale_component __xlocale_global_ctype;
47 extern struct xlocale_component __xlocale_global_monetary;
48 extern struct xlocale_component __xlocale_global_numeric;
49 extern struct xlocale_component __xlocale_global_time;
50 extern struct xlocale_component __xlocale_global_messages;
51 /*
52  * And another version for the statically-allocated C locale.  We only have
53  * components for the parts that are expected to be sensible.
54  */
55 extern struct xlocale_component __xlocale_C_collate;
56 extern struct xlocale_component __xlocale_C_ctype;
57 
58 /*
59  * The locale for this thread.
60  */
61 _Thread_local locale_t __thread_locale;
62 
63 /*
64  * Flag indicating that one or more per-thread locales exist.
65  */
66 int __has_thread_locale;
67 /*
68  * Private functions in setlocale.c.
69  */
70 const char *
71 __get_locale_env(int category);
72 int
73 __detect_path_locale(void);
74 
75 struct _xlocale __xlocale_global_locale = {
76 	{0},
77 	{
78 		&__xlocale_global_collate,
79 		&__xlocale_global_ctype,
80 		&__xlocale_global_monetary,
81 		&__xlocale_global_numeric,
82 		&__xlocale_global_time,
83 		&__xlocale_global_messages
84 	},
85 	1,
86 	0,
87 	1,
88 	0
89 };
90 
91 struct _xlocale __xlocale_C_locale = {
92 	{0},
93 	{
94 		&__xlocale_C_collate,
95 		&__xlocale_C_ctype,
96 		0, 0, 0, 0
97 	},
98 	1,
99 	0,
100 	1,
101 	0
102 };
103 
104 static void*(*constructors[])(const char*, locale_t) =
105 {
106 	__collate_load,
107 	__ctype_load,
108 	__monetary_load,
109 	__numeric_load,
110 	__time_load,
111 	__messages_load
112 };
113 
114 static pthread_key_t locale_info_key;
115 static int fake_tls;
116 static locale_t thread_local_locale;
117 
118 static void init_key(void)
119 {
120 
121 	pthread_key_create(&locale_info_key, xlocale_release);
122 	pthread_setspecific(locale_info_key, (void*)42);
123 	if (pthread_getspecific(locale_info_key) == (void*)42) {
124 		pthread_setspecific(locale_info_key, 0);
125 	} else {
126 		fake_tls = 1;
127 	}
128 	/* At least one per-thread locale has now been set. */
129 	__has_thread_locale = 1;
130 	__detect_path_locale();
131 }
132 
133 static pthread_once_t once_control = PTHREAD_ONCE_INIT;
134 
135 static locale_t
136 get_thread_locale(void)
137 {
138 
139 	_once(&once_control, init_key);
140 
141 	return (fake_tls ? thread_local_locale :
142 		pthread_getspecific(locale_info_key));
143 }
144 
145 static void
146 set_thread_locale(locale_t loc)
147 {
148 	locale_t l = (loc == LC_GLOBAL_LOCALE) ? 0 : loc;
149 
150 	_once(&once_control, init_key);
151 
152 	if (NULL != l) {
153 		xlocale_retain((struct xlocale_refcounted*)l);
154 	}
155 	locale_t old = get_thread_locale();
156 	if ((NULL != old) && (l != old)) {
157 		xlocale_release((struct xlocale_refcounted*)old);
158 	}
159 	if (fake_tls) {
160 		thread_local_locale = l;
161 	} else {
162 		pthread_setspecific(locale_info_key, l);
163 	}
164 	__thread_locale = l;
165 	__set_thread_rune_locale(loc);
166 }
167 
168 /**
169  * Clean up a locale, once its reference count reaches zero.  This function is
170  * called by xlocale_release(), it should not be called directly.
171  */
172 static void
173 destruct_locale(void *l)
174 {
175 	locale_t loc = l;
176 
177 	for (int type=0 ; type<XLC_LAST ; type++) {
178 		if (loc->components[type]) {
179 			xlocale_release(loc->components[type]);
180 		}
181 	}
182 	if (loc->csym) {
183 		free(loc->csym);
184 	}
185 	free(l);
186 }
187 
188 /**
189  * Allocates a new, uninitialised, locale.
190  */
191 static locale_t
192 alloc_locale(void)
193 {
194 	locale_t new = calloc(sizeof(struct _xlocale), 1);
195 
196 	new->header.destructor = destruct_locale;
197 	new->monetary_locale_changed = 1;
198 	new->numeric_locale_changed = 1;
199 	return (new);
200 }
201 static void
202 copyflags(locale_t new, locale_t old)
203 {
204 	new->using_monetary_locale = old->using_monetary_locale;
205 	new->using_numeric_locale = old->using_numeric_locale;
206 	new->using_time_locale = old->using_time_locale;
207 	new->using_messages_locale = old->using_messages_locale;
208 }
209 
210 static int dupcomponent(int type, locale_t base, locale_t new)
211 {
212 	/* Always copy from the global locale, since it has mutable components.
213 	 */
214 	struct xlocale_component *src = base->components[type];
215 
216 	if (&__xlocale_global_locale == base) {
217 		new->components[type] = constructors[type](src->locale, new);
218 		if (new->components[type]) {
219 			strncpy(new->components[type]->locale, src->locale,
220 			    ENCODING_LEN);
221 			strncpy(new->components[type]->version, src->version,
222 			    XLOCALE_DEF_VERSION_LEN);
223 		}
224 	} else if (base->components[type]) {
225 		new->components[type] = xlocale_retain(base->components[type]);
226 	} else {
227 		/* If the component was NULL, return success - if base is a
228 		 * valid locale then the flag indicating that this isn't
229 		 * present should be set.  If it isn't a valid locale, then
230 		 * we're stuck anyway. */
231 		return 1;
232 	}
233 	return (0 != new->components[type]);
234 }
235 
236 /*
237  * Public interfaces.  These are the five public functions described by the
238  * xlocale interface.
239  */
240 
241 locale_t newlocale(int mask, const char *locale, locale_t base)
242 {
243 	locale_t orig_base;
244 	int type;
245 	const char *realLocale = locale;
246 	int useenv = 0;
247 	int success = 1;
248 
249 	_once(&once_control, init_key);
250 
251 	locale_t new = alloc_locale();
252 	if (NULL == new) {
253 		return (NULL);
254 	}
255 
256 	orig_base = base;
257 	FIX_LOCALE(base);
258 	copyflags(new, base);
259 
260 	if (NULL == locale) {
261 		realLocale = "C";
262 	} else if ('\0' == locale[0]) {
263 		useenv = 1;
264 	}
265 
266 	for (type=0 ; type<XLC_LAST ; type++) {
267 		if (mask & 1) {
268 			if (useenv) {
269 				realLocale = __get_locale_env(type + 1);
270 			}
271 			new->components[type] =
272 			     constructors[type](realLocale, new);
273 			if (new->components[type]) {
274 				strncpy(new->components[type]->locale,
275 				     realLocale, ENCODING_LEN);
276 			} else {
277 				success = 0;
278 				break;
279 			}
280 		} else {
281 			if (!dupcomponent(type, base, new)) {
282 				success = 0;
283 				break;
284 			}
285 		}
286 		mask >>= 1;
287 	}
288 	if (0 == success) {
289 		xlocale_release(new);
290 		new = NULL;
291 	} else if (base == orig_base) {
292 		xlocale_release(base);
293 	}
294 
295 	return (new);
296 }
297 
298 locale_t duplocale(locale_t base)
299 {
300 	locale_t new = alloc_locale();
301 	int type;
302 
303 	_once(&once_control, init_key);
304 
305 	if (NULL == new) {
306 		return (NULL);
307 	}
308 
309 	FIX_LOCALE(base);
310 	copyflags(new, base);
311 
312 	for (type=0 ; type<XLC_LAST ; type++) {
313 		dupcomponent(type, base, new);
314 	}
315 
316 	return (new);
317 }
318 
319 /*
320  * Free a locale_t.  This is quite a poorly named function.  It actually
321  * disclaims a reference to a locale_t, rather than freeing it.
322  */
323 void
324 freelocale(locale_t loc)
325 {
326 
327 	/*
328 	 * Fail if we're passed something that isn't a locale. If we're
329 	 * passed the global locale, pretend that we freed it but don't
330 	 * actually do anything.
331 	 */
332 	if (loc != NULL && loc != LC_GLOBAL_LOCALE &&
333 	    loc != &__xlocale_global_locale)
334 		xlocale_release(loc);
335 }
336 
337 /*
338  * Returns the name or version of the locale for a particular component of a
339  * locale_t.
340  */
341 const char *querylocale(int mask, locale_t loc)
342 {
343 	int type = ffs(mask & ~LC_VERSION_MASK) - 1;
344 	FIX_LOCALE(loc);
345 	if (type >= XLC_LAST)
346 		return (NULL);
347 	if (mask & LC_VERSION_MASK) {
348 		if (loc->components[type])
349 			return (loc->components[type]->version);
350 		return ("");
351 	} else {
352 		if (loc->components[type])
353 			return (loc->components[type]->locale);
354 		return ("C");
355 	}
356 }
357 
358 /*
359  * Installs the specified locale_t as this thread's locale.
360  */
361 locale_t uselocale(locale_t loc)
362 {
363 	locale_t old = get_thread_locale();
364 	if (NULL != loc) {
365 		set_thread_locale(loc);
366 	}
367 	return (old ? old : LC_GLOBAL_LOCALE);
368 }
369 
370