xref: /freebsd/lib/libc/locale/xlocale.c (revision d5b0e70f7e04d971691517ce1304d86a1e367e2e)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
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  * $FreeBSD$
31  */
32 
33 #include <pthread.h>
34 #include <stdio.h>
35 #include <string.h>
36 #include <runetype.h>
37 #include "libc_private.h"
38 #include "xlocale_private.h"
39 
40 /**
41  * Each locale loader declares a global component.  This is used by setlocale()
42  * and also by xlocale with LC_GLOBAL_LOCALE..
43  */
44 extern struct xlocale_component __xlocale_global_collate;
45 extern struct xlocale_component __xlocale_global_ctype;
46 extern struct xlocale_component __xlocale_global_monetary;
47 extern struct xlocale_component __xlocale_global_numeric;
48 extern struct xlocale_component __xlocale_global_time;
49 extern struct xlocale_component __xlocale_global_messages;
50 /*
51  * And another version for the statically-allocated C locale.  We only have
52  * components for the parts that are expected to be sensible.
53  */
54 extern struct xlocale_component __xlocale_C_collate;
55 extern struct xlocale_component __xlocale_C_ctype;
56 
57 /*
58  * The locale for this thread.
59  */
60 _Thread_local locale_t __thread_locale;
61 
62 /*
63  * Flag indicating that one or more per-thread locales exist.
64  */
65 int __has_thread_locale;
66 
67 /*
68  * Private functions in setlocale.c.
69  */
70 const char *__get_locale_env(int category);
71 int __detect_path_locale(void);
72 
73 struct _xlocale __xlocale_global_locale = {
74 	{0},
75 	{
76 		&__xlocale_global_collate,
77 		&__xlocale_global_ctype,
78 		&__xlocale_global_monetary,
79 		&__xlocale_global_numeric,
80 		&__xlocale_global_time,
81 		&__xlocale_global_messages
82 	},
83 	1,
84 	0,
85 	1,
86 	0
87 };
88 
89 struct _xlocale __xlocale_C_locale = {
90 	{0},
91 	{
92 		&__xlocale_C_collate,
93 		&__xlocale_C_ctype,
94 		0, 0, 0, 0
95 	},
96 	1,
97 	0,
98 	1,
99 	0
100 };
101 
102 static void *(*constructors[])(const char *, locale_t) =
103 {
104 	__collate_load,
105 	__ctype_load,
106 	__monetary_load,
107 	__numeric_load,
108 	__time_load,
109 	__messages_load
110 };
111 
112 static pthread_key_t locale_info_key;
113 static int fake_tls;
114 static locale_t thread_local_locale;
115 
116 static void
117 init_key(void)
118 {
119 	int error;
120 
121 	error = pthread_key_create(&locale_info_key, xlocale_release);
122 	if (error == 0) {
123 		pthread_setspecific(locale_info_key, (void*)42);
124 		if (pthread_getspecific(locale_info_key) == (void*)42) {
125 			pthread_setspecific(locale_info_key, 0);
126 		} else {
127 			fake_tls = 1;
128 		}
129 	} else {
130 		fake_tls = 1;
131 	}
132 	/* At least one per-thread locale has now been set. */
133 	__has_thread_locale = 1;
134 	__detect_path_locale();
135 }
136 
137 static pthread_once_t once_control = PTHREAD_ONCE_INIT;
138 
139 static locale_t
140 get_thread_locale(void)
141 {
142 
143 	_once(&once_control, init_key);
144 
145 	return (fake_tls ? thread_local_locale :
146 	    pthread_getspecific(locale_info_key));
147 }
148 
149 static void
150 set_thread_locale(locale_t loc)
151 {
152 	locale_t l = (loc == LC_GLOBAL_LOCALE) ? 0 : loc;
153 
154 	_once(&once_control, init_key);
155 
156 	if (NULL != l) {
157 		xlocale_retain((struct xlocale_refcounted*)l);
158 	}
159 	locale_t old = get_thread_locale();
160 	if ((NULL != old) && (l != old)) {
161 		xlocale_release((struct xlocale_refcounted*)old);
162 	}
163 	if (fake_tls) {
164 		thread_local_locale = l;
165 	} else {
166 		pthread_setspecific(locale_info_key, l);
167 	}
168 	__thread_locale = l;
169 	__set_thread_rune_locale(loc);
170 }
171 
172 /**
173  * Clean up a locale, once its reference count reaches zero.  This function is
174  * called by xlocale_release(), it should not be called directly.
175  */
176 static void
177 destruct_locale(void *l)
178 {
179 	locale_t loc = l;
180 
181 	for (int type=0 ; type<XLC_LAST ; type++) {
182 		if (loc->components[type]) {
183 			xlocale_release(loc->components[type]);
184 		}
185 	}
186 	if (loc->csym) {
187 		free(loc->csym);
188 	}
189 	free(l);
190 }
191 
192 /**
193  * Allocates a new, uninitialised, locale.
194  */
195 static locale_t
196 alloc_locale(void)
197 {
198 	locale_t new = calloc(sizeof(struct _xlocale), 1);
199 
200 	if (new == NULL)
201 		return (NULL);
202 
203 	new->header.destructor = destruct_locale;
204 	new->monetary_locale_changed = 1;
205 	new->numeric_locale_changed = 1;
206 	return (new);
207 }
208 
209 static void
210 copyflags(locale_t new, locale_t old)
211 {
212 	new->using_monetary_locale = old->using_monetary_locale;
213 	new->using_numeric_locale = old->using_numeric_locale;
214 	new->using_time_locale = old->using_time_locale;
215 	new->using_messages_locale = old->using_messages_locale;
216 }
217 
218 static int
219 dupcomponent(int type, locale_t base, locale_t new)
220 {
221 	/* Always copy from the global locale, since it has mutable components.
222 	 */
223 	struct xlocale_component *src = base->components[type];
224 
225 	if (&__xlocale_global_locale == base) {
226 		new->components[type] = constructors[type](src->locale, new);
227 		if (new->components[type]) {
228 			strncpy(new->components[type]->locale, src->locale,
229 			    ENCODING_LEN);
230 			strncpy(new->components[type]->version, src->version,
231 			    XLOCALE_DEF_VERSION_LEN);
232 		}
233 	} else if (base->components[type]) {
234 		new->components[type] = xlocale_retain(base->components[type]);
235 	} else {
236 		/* If the component was NULL, return success - if base is a
237 		 * valid locale then the flag indicating that this isn't
238 		 * present should be set.  If it isn't a valid locale, then
239 		 * we're stuck anyway. */
240 		return 1;
241 	}
242 	return (0 != new->components[type]);
243 }
244 
245 /*
246  * Public interfaces.  These are the five public functions described by the
247  * xlocale interface.
248  */
249 
250 locale_t
251 newlocale(int mask, const char *locale, locale_t base)
252 {
253 	locale_t orig_base;
254 	int type;
255 	const char *realLocale = locale;
256 	int useenv = 0;
257 	int success = 1;
258 
259 	locale_t new = alloc_locale();
260 	if (NULL == new) {
261 		return (NULL);
262 	}
263 
264 	_once(&once_control, init_key);
265 
266 	orig_base = base;
267 	FIX_LOCALE(base);
268 	copyflags(new, base);
269 
270 	if (NULL == locale) {
271 		realLocale = "C";
272 	} else if ('\0' == locale[0]) {
273 		useenv = 1;
274 	}
275 
276 	for (type=0 ; type<XLC_LAST ; type++) {
277 		if (mask & 1) {
278 			if (useenv) {
279 				realLocale = __get_locale_env(type + 1);
280 			}
281 			new->components[type] =
282 			     constructors[type](realLocale, new);
283 			if (new->components[type]) {
284 				strncpy(new->components[type]->locale,
285 				     realLocale, ENCODING_LEN);
286 			} else {
287 				success = 0;
288 				break;
289 			}
290 		} else {
291 			if (!dupcomponent(type, base, new)) {
292 				success = 0;
293 				break;
294 			}
295 		}
296 		mask >>= 1;
297 	}
298 	if (0 == success) {
299 		xlocale_release(new);
300 		new = NULL;
301 	} else if (base == orig_base) {
302 		xlocale_release(base);
303 	}
304 
305 	return (new);
306 }
307 
308 locale_t
309 duplocale(locale_t base)
310 {
311 	locale_t new = alloc_locale();
312 	int type;
313 
314 	if (NULL == new) {
315 		return (NULL);
316 	}
317 
318 	_once(&once_control, init_key);
319 
320 	FIX_LOCALE(base);
321 	copyflags(new, base);
322 
323 	for (type=0 ; type<XLC_LAST ; type++) {
324 		dupcomponent(type, base, new);
325 	}
326 
327 	return (new);
328 }
329 
330 /*
331  * Free a locale_t.  This is quite a poorly named function.  It actually
332  * disclaims a reference to a locale_t, rather than freeing it.
333  */
334 void
335 freelocale(locale_t loc)
336 {
337 
338 	/*
339 	 * Fail if we're passed something that isn't a locale. If we're
340 	 * passed the global locale, pretend that we freed it but don't
341 	 * actually do anything.
342 	 */
343 	if (loc != NULL && loc != LC_GLOBAL_LOCALE &&
344 	    loc != &__xlocale_global_locale)
345 		xlocale_release(loc);
346 }
347 
348 /*
349  * Returns the name or version of the locale for a particular component of a
350  * locale_t.
351  */
352 const char *
353 querylocale(int mask, locale_t loc)
354 {
355 	int type = ffs(mask & ~LC_VERSION_MASK) - 1;
356 	FIX_LOCALE(loc);
357 	if (type >= XLC_LAST)
358 		return (NULL);
359 	if (mask & LC_VERSION_MASK) {
360 		if (loc->components[type])
361 			return (loc->components[type]->version);
362 		return ("");
363 	} else {
364 		if (loc->components[type])
365 			return (loc->components[type]->locale);
366 		return ("C");
367 	}
368 }
369 
370 /*
371  * Installs the specified locale_t as this thread's locale.
372  */
373 locale_t
374 uselocale(locale_t loc)
375 {
376 	locale_t old = get_thread_locale();
377 	if (NULL != loc) {
378 		set_thread_locale(loc);
379 	}
380 	return (old ? old : LC_GLOBAL_LOCALE);
381 }
382 
383