xlocale.c revision 284985 
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: releng/10.1/lib/libc/locale/xlocale.c 284985 2015-06-30 23:21:37Z delphij $
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	locale_t l = (loc == LC_GLOBAL_LOCALE) ? 0 : loc;
158
159	_once(&once_control, init_key);
160
161	if (NULL != l) {
162		xlocale_retain((struct xlocale_refcounted*)l);
163	}
164	locale_t old = pthread_getspecific(locale_info_key);
165	if ((NULL != old) && (l != old)) {
166		xlocale_release((struct xlocale_refcounted*)old);
167	}
168	if (fake_tls) {
169		thread_local_locale = l;
170	} else {
171		pthread_setspecific(locale_info_key, l);
172	}
173#ifndef __NO_TLS
174	__thread_locale = l;
175	__set_thread_rune_locale(loc);
176#endif
177}
178
179/**
180 * Clean up a locale, once its reference count reaches zero.  This function is
181 * called by xlocale_release(), it should not be called directly.
182 */
183static void
184destruct_locale(void *l)
185{
186	locale_t loc = l;
187
188	for (int type=0 ; type<XLC_LAST ; type++) {
189		if (loc->components[type]) {
190			xlocale_release(loc->components[type]);
191		}
192	}
193	if (loc->csym) {
194		free(loc->csym);
195	}
196	free(l);
197}
198
199/**
200 * Allocates a new, uninitialised, locale.
201 */
202static locale_t
203alloc_locale(void)
204{
205	locale_t new = calloc(sizeof(struct _xlocale), 1);
206
207	new->header.destructor = destruct_locale;
208	new->monetary_locale_changed = 1;
209	new->numeric_locale_changed = 1;
210	return (new);
211}
212static void
213copyflags(locale_t new, locale_t old)
214{
215	new->using_monetary_locale = old->using_monetary_locale;
216	new->using_numeric_locale = old->using_numeric_locale;
217	new->using_time_locale = old->using_time_locale;
218	new->using_messages_locale = old->using_messages_locale;
219}
220
221static int dupcomponent(int type, locale_t base, locale_t new)
222{
223	/* Always copy from the global locale, since it has mutable components.
224	 */
225	struct xlocale_component *src = base->components[type];
226
227	if (&__xlocale_global_locale == base) {
228		new->components[type] = constructors[type](src->locale, new);
229		if (new->components[type]) {
230			strncpy(new->components[type]->locale, src->locale,
231			    ENCODING_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
250locale_t newlocale(int mask, const char *locale, locale_t base)
251{
252	int type;
253	const char *realLocale = locale;
254	int useenv = 0;
255	int success = 1;
256
257	_once(&once_control, init_key);
258
259	locale_t new = alloc_locale();
260	if (NULL == new) {
261		return (NULL);
262	}
263
264	FIX_LOCALE(base);
265	copyflags(new, base);
266
267	if (NULL == locale) {
268		realLocale = "C";
269	} else if ('\0' == locale[0]) {
270		useenv = 1;
271	}
272
273	for (type=0 ; type<XLC_LAST ; type++) {
274		if (mask & 1) {
275			if (useenv) {
276				realLocale = __get_locale_env(type);
277			}
278			new->components[type] =
279			     constructors[type](realLocale, new);
280			if (new->components[type]) {
281				strncpy(new->components[type]->locale,
282				     realLocale, ENCODING_LEN);
283			} else {
284				success = 0;
285				break;
286			}
287		} else {
288			if (!dupcomponent(type, base, new)) {
289				success = 0;
290				break;
291			}
292		}
293		mask >>= 1;
294	}
295	if (0 == success) {
296		xlocale_release(new);
297		new = NULL;
298	}
299
300	return (new);
301}
302
303locale_t duplocale(locale_t base)
304{
305	locale_t new = alloc_locale();
306	int type;
307
308	_once(&once_control, init_key);
309
310	if (NULL == new) {
311		return (NULL);
312	}
313
314	FIX_LOCALE(base);
315	copyflags(new, base);
316
317	for (type=0 ; type<XLC_LAST ; type++) {
318		dupcomponent(type, base, new);
319	}
320
321	return (new);
322}
323
324/*
325 * Free a locale_t.  This is quite a poorly named function.  It actually
326 * disclaims a reference to a locale_t, rather than freeing it.
327 */
328int
329freelocale(locale_t loc)
330{
331	/* Fail if we're passed something that isn't a locale. */
332	if ((NULL == loc) || (LC_GLOBAL_LOCALE == loc)) {
333		return (-1);
334	}
335	/* If we're passed the global locale, pretend that we freed it but don't
336	 * actually do anything. */
337	if (&__xlocale_global_locale == loc) {
338		return (0);
339	}
340	xlocale_release(loc);
341	return (0);
342}
343
344/*
345 * Returns the name of the locale for a particular component of a locale_t.
346 */
347const char *querylocale(int mask, locale_t loc)
348{
349	int type = ffs(mask) - 1;
350	FIX_LOCALE(loc);
351	if (type >= XLC_LAST)
352		return (NULL);
353	if (loc->components[type])
354		return (loc->components[type]->locale);
355	return ("C");
356}
357
358/*
359 * Installs the specified locale_t as this thread's locale.
360 */
361locale_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