xlocale.c revision 232498 
1/*-
2 * Copyright (c) 2011 The FreeBSD Foundation
3 * All rights reserved.
4 *
5 * This software was developed by David Chisnall under sponsorship from
6 * the FreeBSD Foundation.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 *    notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 *
29 * $FreeBSD: head/lib/libc/locale/xlocale.c 232498 2012-03-04 15:31:13Z theraven $
30 */
31
32#include <pthread.h>
33#include <stdio.h>
34#include <string.h>
35#include <runetype.h>
36#include "libc_private.h"
37#include "xlocale_private.h"
38
39/**
40 * Each locale loader declares a global component.  This is used by setlocale()
41 * and also by xlocale with LC_GLOBAL_LOCALE..
42 */
43extern struct xlocale_component __xlocale_global_collate;
44extern struct xlocale_component __xlocale_global_ctype;
45extern struct xlocale_component __xlocale_global_monetary;
46extern struct xlocale_component __xlocale_global_numeric;
47extern struct xlocale_component __xlocale_global_time;
48extern struct xlocale_component __xlocale_global_messages;
49/*
50 * And another version for the statically-allocated C locale.  We only have
51 * components for the parts that are expected to be sensible.
52 */
53extern struct xlocale_component __xlocale_C_collate;
54extern struct xlocale_component __xlocale_C_ctype;
55
56#ifndef __NO_TLS
57/*
58 * The locale for this thread.
59 */
60_Thread_local locale_t __thread_locale;
61#endif
62/*
63 * Flag indicating that one or more per-thread locales exist.
64 */
65int __has_thread_locale;
66/*
67 * Private functions in setlocale.c.
68 */
69const char *
70__get_locale_env(int category);
71int
72__detect_path_locale(void);
73
74struct _xlocale __xlocale_global_locale = {
75	{0},
76	{
77		&__xlocale_global_collate,
78		&__xlocale_global_ctype,
79		&__xlocale_global_monetary,
80		&__xlocale_global_numeric,
81		&__xlocale_global_time,
82		&__xlocale_global_messages
83	},
84	1,
85	0,
86	1,
87	0
88};
89
90struct _xlocale __xlocale_C_locale = {
91	{0},
92	{
93		&__xlocale_C_collate,
94		&__xlocale_C_ctype,
95		0, 0, 0, 0
96	},
97	1,
98	0,
99	1,
100	0
101};
102
103static void*(*constructors[])(const char*, locale_t) =
104{
105	__collate_load,
106	__ctype_load,
107	__monetary_load,
108	__numeric_load,
109	__time_load,
110	__messages_load
111};
112
113static pthread_key_t locale_info_key;
114static int fake_tls;
115static locale_t thread_local_locale;
116
117static void init_key(void)
118{
119
120	pthread_key_create(&locale_info_key, xlocale_release);
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	/* At least one per-thread locale has now been set. */
128	__has_thread_locale = 1;
129	__detect_path_locale();
130}
131
132static pthread_once_t once_control = PTHREAD_ONCE_INIT;
133
134static locale_t
135get_thread_locale(void)
136{
137
138	_once(&once_control, init_key);
139
140	return (fake_tls ? thread_local_locale :
141		pthread_getspecific(locale_info_key));
142}
143
144#ifdef __NO_TLS
145locale_t
146__get_locale(void)
147{
148	locale_t l = get_thread_locale();
149	return (l ? l : &__xlocale_global_locale);
150
151}
152#endif
153
154static void
155set_thread_locale(locale_t loc)
156{
157
158	_once(&once_control, init_key);
159
160	if (NULL != loc) {
161		xlocale_retain((struct xlocale_refcounted*)loc);
162	}
163	locale_t old = pthread_getspecific(locale_info_key);
164	if ((NULL != old) && (loc != old)) {
165		xlocale_release((struct xlocale_refcounted*)old);
166	}
167	if (fake_tls) {
168		thread_local_locale = loc;
169	} else {
170		pthread_setspecific(locale_info_key, loc);
171	}
172#ifndef __NO_TLS
173	__thread_locale = loc;
174	__set_thread_rune_locale(loc);
175#endif
176}
177
178/**
179 * Clean up a locale, once its reference count reaches zero.  This function is
180 * called by xlocale_release(), it should not be called directly.
181 */
182static void
183destruct_locale(void *l)
184{
185	locale_t loc = l;
186
187	for (int type=0 ; type<XLC_LAST ; type++) {
188		if (loc->components[type]) {
189			xlocale_release(loc->components[type]);
190		}
191	}
192	if (loc->csym) {
193		free(loc->csym);
194	}
195	free(l);
196}
197
198/**
199 * Allocates a new, uninitialised, locale.
200 */
201static locale_t
202alloc_locale(void)
203{
204	locale_t new = calloc(sizeof(struct _xlocale), 1);
205
206	new->header.destructor = destruct_locale;
207	new->monetary_locale_changed = 1;
208	new->numeric_locale_changed = 1;
209	return (new);
210}
211static void
212copyflags(locale_t new, locale_t old)
213{
214	new->using_monetary_locale = old->using_monetary_locale;
215	new->using_numeric_locale = old->using_numeric_locale;
216	new->using_time_locale = old->using_time_locale;
217	new->using_messages_locale = old->using_messages_locale;
218}
219
220static int dupcomponent(int type, locale_t base, locale_t new)
221{
222	/* Always copy from the global locale, since it has mutable components.
223	 */
224	struct xlocale_component *src = base->components[type];
225
226	if (&__xlocale_global_locale == base) {
227		new->components[type] = constructors[type](src->locale, new);
228		if (new->components[type]) {
229			strncpy(new->components[type]->locale, src->locale,
230			    ENCODING_LEN);
231		}
232	} else if (base->components[type]) {
233		new->components[type] = xlocale_retain(base->components[type]);
234	} else {
235		/* If the component was NULL, return success - if base is a
236		 * valid locale then the flag indicating that this isn't
237		 * present should be set.  If it isn't a valid locale, then
238		 * we're stuck anyway. */
239		return 1;
240	}
241	return (0 != new->components[type]);
242}
243
244/*
245 * Public interfaces.  These are the five public functions described by the
246 * xlocale interface.
247 */
248
249locale_t newlocale(int mask, const char *locale, locale_t base)
250{
251	int type;
252	const char *realLocale = locale;
253	int useenv = 0;
254	int success = 1;
255
256	_once(&once_control, init_key);
257
258	locale_t new = alloc_locale();
259	if (NULL == new) {
260		return (NULL);
261	}
262
263	FIX_LOCALE(base);
264	copyflags(new, base);
265
266	if (NULL == locale) {
267		realLocale = "C";
268	} else if ('\0' == locale[0]) {
269		useenv = 1;
270	}
271
272	for (type=0 ; type<XLC_LAST ; type++) {
273		if (mask & 1) {
274			if (useenv) {
275				realLocale = __get_locale_env(type);
276			}
277			new->components[type] =
278			     constructors[type](realLocale, new);
279			if (new->components[type]) {
280				strncpy(new->components[type]->locale,
281				     realLocale, ENCODING_LEN);
282			} else {
283				success = 0;
284				break;
285			}
286		} else {
287			if (!dupcomponent(type, base, new)) {
288				success = 0;
289				break;
290			}
291		}
292		mask >>= 1;
293	}
294	if (0 == success) {
295		xlocale_release(new);
296		new = NULL;
297	}
298
299	return (new);
300}
301
302locale_t duplocale(locale_t base)
303{
304	locale_t new = alloc_locale();
305	int type;
306
307	_once(&once_control, init_key);
308
309	if (NULL == new) {
310		return (NULL);
311	}
312
313	FIX_LOCALE(base);
314	copyflags(new, base);
315
316	for (type=0 ; type<XLC_LAST ; type++) {
317		dupcomponent(type, base, new);
318	}
319
320	return (new);
321}
322
323/*
324 * Free a locale_t.  This is quite a poorly named function.  It actually
325 * disclaims a reference to a locale_t, rather than freeing it.
326 */
327int
328freelocale(locale_t loc)
329{
330	/* Fail if we're passed something that isn't a locale. */
331	if ((NULL == loc) || (LC_GLOBAL_LOCALE == loc)) {
332		return (-1);
333	}
334	/* If we're passed the global locale, pretend that we freed it but don't
335	 * actually do anything. */
336	if (&__xlocale_global_locale == loc) {
337		return (0);
338	}
339	xlocale_release(loc);
340	return (0);
341}
342
343/*
344 * Returns the name of the locale for a particular component of a locale_t.
345 */
346const char *querylocale(int mask, locale_t loc)
347{
348	int type = ffs(mask) - 1;
349	FIX_LOCALE(loc);
350	if (type >= XLC_LAST)
351		return (NULL);
352	if (loc->components[type])
353		return (loc->components[type]->locale);
354	return ("C");
355}
356
357/*
358 * Installs the specified locale_t as this thread's locale.
359 */
360locale_t uselocale(locale_t loc)
361{
362	locale_t old = get_thread_locale();
363	if (NULL != loc) {
364		if (LC_GLOBAL_LOCALE == loc) {
365			loc = NULL;
366		}
367		set_thread_locale(loc);
368	}
369	return (old ? old : LC_GLOBAL_LOCALE);
370}
371
372