xref: /freebsd/lib/libc/locale/xlocale.c (revision 2e3f49888ec8851bafb22011533217487764fdb0)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2011 The FreeBSD Foundation
5  *
6  * This software was developed by David Chisnall under sponsorship from
7  * the FreeBSD Foundation.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28  * SUCH DAMAGE.
29  */
30 
31 #include <pthread.h>
32 #include <stdio.h>
33 #include <string.h>
34 #include <runetype.h>
35 #include "libc_private.h"
36 #include "xlocale_private.h"
37 
38 /**
39  * Each locale loader declares a global component.  This is used by setlocale()
40  * and also by xlocale with LC_GLOBAL_LOCALE..
41  */
42 extern struct xlocale_component __xlocale_global_collate;
43 extern struct xlocale_component __xlocale_global_ctype;
44 extern struct xlocale_component __xlocale_global_monetary;
45 extern struct xlocale_component __xlocale_global_numeric;
46 extern struct xlocale_component __xlocale_global_time;
47 extern struct xlocale_component __xlocale_global_messages;
48 /*
49  * And another version for the statically-allocated C locale.  We only have
50  * components for the parts that are expected to be sensible.
51  */
52 extern struct xlocale_component __xlocale_C_collate;
53 extern struct xlocale_component __xlocale_C_ctype;
54 
55 /*
56  * The locale for this thread.
57  */
58 _Thread_local locale_t __thread_locale;
59 
60 /*
61  * Flag indicating that one or more per-thread locales exist.
62  */
63 int __has_thread_locale;
64 
65 /*
66  * Private functions in setlocale.c.
67  */
68 const char *__get_locale_env(int category);
69 int __detect_path_locale(void);
70 
71 struct _xlocale __xlocale_global_locale = {
72 	{0},
73 	{
74 		&__xlocale_global_collate,
75 		&__xlocale_global_ctype,
76 		&__xlocale_global_monetary,
77 		&__xlocale_global_numeric,
78 		&__xlocale_global_time,
79 		&__xlocale_global_messages
80 	},
81 	1,
82 	0,
83 	1,
84 	0
85 };
86 
87 struct _xlocale __xlocale_C_locale = {
88 	{0},
89 	{
90 		&__xlocale_C_collate,
91 		&__xlocale_C_ctype,
92 		0, 0, 0, 0
93 	},
94 	1,
95 	0,
96 	1,
97 	0
98 };
99 
100 static void *(*constructors[])(const char *, locale_t) =
101 {
102 	__collate_load,
103 	__ctype_load,
104 	__monetary_load,
105 	__numeric_load,
106 	__time_load,
107 	__messages_load
108 };
109 
110 static pthread_key_t locale_info_key;
111 static int fake_tls;
112 static locale_t thread_local_locale;
113 
114 static void
115 init_key(void)
116 {
117 	int error;
118 
119 	error = pthread_key_create(&locale_info_key, xlocale_release);
120 	if (error == 0) {
121 		pthread_setspecific(locale_info_key, (void*)42);
122 		if (pthread_getspecific(locale_info_key) == (void*)42) {
123 			pthread_setspecific(locale_info_key, 0);
124 		} else {
125 			fake_tls = 1;
126 		}
127 	} else {
128 		fake_tls = 1;
129 	}
130 	/* At least one per-thread locale has now been set. */
131 	__has_thread_locale = 1;
132 	__detect_path_locale();
133 }
134 
135 static pthread_once_t once_control = PTHREAD_ONCE_INIT;
136 
137 static locale_t
138 get_thread_locale(void)
139 {
140 
141 	_once(&once_control, init_key);
142 
143 	return (fake_tls ? thread_local_locale :
144 	    pthread_getspecific(locale_info_key));
145 }
146 
147 static void
148 set_thread_locale(locale_t loc)
149 {
150 	locale_t l = (loc == LC_GLOBAL_LOCALE) ? 0 : loc;
151 
152 	_once(&once_control, init_key);
153 
154 	if (NULL != l) {
155 		xlocale_retain((struct xlocale_refcounted*)l);
156 	}
157 	locale_t old = get_thread_locale();
158 	if ((NULL != old) && (l != old)) {
159 		xlocale_release((struct xlocale_refcounted*)old);
160 	}
161 	if (fake_tls) {
162 		thread_local_locale = l;
163 	} else {
164 		pthread_setspecific(locale_info_key, l);
165 	}
166 	__thread_locale = l;
167 	__set_thread_rune_locale(loc);
168 }
169 
170 /**
171  * Clean up a locale, once its reference count reaches zero.  This function is
172  * called by xlocale_release(), it should not be called directly.
173  */
174 static void
175 destruct_locale(void *l)
176 {
177 	locale_t loc = l;
178 
179 	for (int type=0 ; type<XLC_LAST ; type++) {
180 		if (loc->components[type]) {
181 			xlocale_release(loc->components[type]);
182 		}
183 	}
184 	if (loc->csym) {
185 		free(loc->csym);
186 	}
187 	free(l);
188 }
189 
190 /**
191  * Allocates a new, uninitialised, locale.
192  */
193 static locale_t
194 alloc_locale(void)
195 {
196 	locale_t new = calloc(sizeof(struct _xlocale), 1);
197 
198 	if (new == NULL)
199 		return (NULL);
200 
201 	new->header.destructor = destruct_locale;
202 	new->monetary_locale_changed = 1;
203 	new->numeric_locale_changed = 1;
204 	return (new);
205 }
206 
207 static void
208 copyflags(locale_t new, locale_t old)
209 {
210 	new->using_monetary_locale = old->using_monetary_locale;
211 	new->using_numeric_locale = old->using_numeric_locale;
212 	new->using_time_locale = old->using_time_locale;
213 	new->using_messages_locale = old->using_messages_locale;
214 }
215 
216 static int
217 dupcomponent(int type, locale_t base, locale_t new)
218 {
219 	/* Always copy from the global locale, since it has mutable components.
220 	 */
221 	struct xlocale_component *src = base->components[type];
222 
223 	if (&__xlocale_global_locale == base) {
224 		new->components[type] = constructors[type](src->locale, new);
225 		if (new->components[type]) {
226 			strncpy(new->components[type]->locale, src->locale,
227 			    ENCODING_LEN);
228 			strncpy(new->components[type]->version, src->version,
229 			    XLOCALE_DEF_VERSION_LEN);
230 		}
231 	} else if (base->components[type]) {
232 		new->components[type] = xlocale_retain(base->components[type]);
233 	} else {
234 		/* If the component was NULL, return success - if base is a
235 		 * valid locale then the flag indicating that this isn't
236 		 * present should be set.  If it isn't a valid locale, then
237 		 * we're stuck anyway. */
238 		return 1;
239 	}
240 	return (0 != new->components[type]);
241 }
242 
243 /*
244  * Public interfaces.  These are the five public functions described by the
245  * xlocale interface.
246  */
247 
248 locale_t
249 newlocale(int mask, const char *locale, locale_t base)
250 {
251 	locale_t orig_base;
252 	int type;
253 	const char *realLocale = locale;
254 	int useenv = 0;
255 	int success = 1;
256 
257 	locale_t new = alloc_locale();
258 	if (NULL == new) {
259 		return (NULL);
260 	}
261 
262 	_once(&once_control, init_key);
263 
264 	orig_base = base;
265 	FIX_LOCALE(base);
266 	copyflags(new, base);
267 
268 	if (NULL == locale) {
269 		realLocale = "C";
270 	} else if ('\0' == locale[0]) {
271 		useenv = 1;
272 	}
273 
274 	for (type=0 ; type<XLC_LAST ; type++) {
275 		if (mask & 1) {
276 			if (useenv) {
277 				realLocale = __get_locale_env(type + 1);
278 			}
279 			new->components[type] =
280 			     constructors[type](realLocale, new);
281 			if (new->components[type]) {
282 				strncpy(new->components[type]->locale,
283 				     realLocale, ENCODING_LEN);
284 			} else {
285 				success = 0;
286 				break;
287 			}
288 		} else {
289 			if (!dupcomponent(type, base, new)) {
290 				success = 0;
291 				break;
292 			}
293 		}
294 		mask >>= 1;
295 	}
296 	if (0 == success) {
297 		xlocale_release(new);
298 		new = NULL;
299 	} else if (base == orig_base) {
300 		xlocale_release(base);
301 	}
302 
303 	return (new);
304 }
305 
306 locale_t
307 duplocale(locale_t base)
308 {
309 	locale_t new = alloc_locale();
310 	int type;
311 
312 	if (NULL == new) {
313 		return (NULL);
314 	}
315 
316 	_once(&once_control, init_key);
317 
318 	FIX_LOCALE(base);
319 	copyflags(new, base);
320 
321 	for (type=0 ; type<XLC_LAST ; type++) {
322 		dupcomponent(type, base, new);
323 	}
324 
325 	return (new);
326 }
327 
328 /*
329  * Free a locale_t.  This is quite a poorly named function.  It actually
330  * disclaims a reference to a locale_t, rather than freeing it.
331  */
332 void
333 freelocale(locale_t loc)
334 {
335 
336 	/*
337 	 * Fail if we're passed something that isn't a locale. If we're
338 	 * passed the global locale, pretend that we freed it but don't
339 	 * actually do anything.
340 	 */
341 	if (loc != NULL && loc != LC_GLOBAL_LOCALE &&
342 	    loc != &__xlocale_global_locale)
343 		xlocale_release(loc);
344 }
345 
346 /*
347  * Returns the name or version of the locale for a particular component of a
348  * locale_t.
349  */
350 const char *
351 querylocale(int mask, locale_t loc)
352 {
353 	int type = ffs(mask & ~LC_VERSION_MASK) - 1;
354 	FIX_LOCALE(loc);
355 	if (type >= XLC_LAST)
356 		return (NULL);
357 	if (mask & LC_VERSION_MASK) {
358 		if (loc->components[type])
359 			return (loc->components[type]->version);
360 		return ("");
361 	} else {
362 		if (loc->components[type])
363 			return (loc->components[type]->locale);
364 		return ("C");
365 	}
366 }
367 
368 /*
369  * Installs the specified locale_t as this thread's locale.
370  */
371 locale_t
372 uselocale(locale_t loc)
373 {
374 	locale_t old = get_thread_locale();
375 	if (NULL != loc) {
376 		set_thread_locale(loc);
377 	}
378 	return (old ? old : LC_GLOBAL_LOCALE);
379 }
380 
381