xref: /freebsd/lib/libc/locale/xlocale_private.h (revision a7623790fb345e6dc986dfd31df0ace115e6f2e4)
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 #ifndef _XLOCALE_PRIVATE__H_
35 #define _XLOCALE_PRIVATE__H_
36 
37 #include <xlocale.h>
38 #include <locale.h>
39 #include <stdlib.h>
40 #include <stdint.h>
41 #include <sys/types.h>
42 #include <machine/atomic.h>
43 #include "setlocale.h"
44 
45 /**
46  * The XLC_ values are indexes into the components array.  They are defined in
47  * the same order as the LC_ values in locale.h, but without the LC_ALL zero
48  * value.  Translating from LC_X to XLC_X is done by subtracting one.
49  *
50  * Any reordering of this enum should ensure that these invariants are not
51  * violated.
52  */
53 enum {
54 	XLC_COLLATE = 0,
55 	XLC_CTYPE,
56 	XLC_MONETARY,
57 	XLC_NUMERIC,
58 	XLC_TIME,
59 	XLC_MESSAGES,
60 	XLC_LAST
61 };
62 
63 _Static_assert(XLC_LAST - XLC_COLLATE == 6, "XLC values should be contiguous");
64 _Static_assert(XLC_COLLATE == LC_COLLATE - 1,
65                "XLC_COLLATE doesn't match the LC_COLLATE value.");
66 _Static_assert(XLC_CTYPE == LC_CTYPE - 1,
67                "XLC_CTYPE doesn't match the LC_CTYPE value.");
68 _Static_assert(XLC_MONETARY == LC_MONETARY - 1,
69                "XLC_MONETARY doesn't match the LC_MONETARY value.");
70 _Static_assert(XLC_NUMERIC == LC_NUMERIC - 1,
71                "XLC_NUMERIC doesn't match the LC_NUMERIC value.");
72 _Static_assert(XLC_TIME == LC_TIME - 1,
73                "XLC_TIME doesn't match the LC_TIME value.");
74 _Static_assert(XLC_MESSAGES == LC_MESSAGES - 1,
75                "XLC_MESSAGES doesn't match the LC_MESSAGES value.");
76 
77 /**
78  * Header used for objects that are reference counted.  Objects may optionally
79  * have a destructor associated, which is responsible for destroying the
80  * structure.  Global / static versions of the structure should have no
81  * destructor set - they can then have their reference counts manipulated as
82  * normal, but will not do anything with them.
83  *
84  * The header stores a retain count - objects are assumed to have a reference
85  * count of 1 when they are created, but the retain count is 0.  When the
86  * retain count is less than 0, they are freed.
87  */
88 struct xlocale_refcounted {
89 	/** Number of references to this component.  */
90 	long retain_count;
91 	/** Function used to destroy this component, if one is required*/
92 	void(*destructor)(void*);
93 };
94 
95 #define XLOCALE_DEF_VERSION_LEN 12
96 
97 /**
98  * Header for a locale component.  All locale components must begin with this
99  * header.
100  */
101 struct xlocale_component {
102 	struct xlocale_refcounted header;
103 	/** Name of the locale used for this component. */
104 	char locale[ENCODING_LEN+1];
105 	/** Version of the definition for this component. */
106 	char version[XLOCALE_DEF_VERSION_LEN];
107 };
108 
109 /**
110  * xlocale structure, stores per-thread locale information.
111  */
112 struct _xlocale {
113 	struct xlocale_refcounted header;
114 	/** Components for the locale.  */
115 	struct xlocale_component *components[XLC_LAST];
116 	/** Flag indicating if components[XLC_MONETARY] has changed since the
117 	 * last call to localeconv_l() with this locale. */
118 	int monetary_locale_changed;
119 	/** Flag indicating whether this locale is actually using a locale for
120 	 * LC_MONETARY (1), or if it should use the C default instead (0). */
121 	int using_monetary_locale;
122 	/** Flag indicating if components[XLC_NUMERIC] has changed since the
123 	 * last call to localeconv_l() with this locale. */
124 	int numeric_locale_changed;
125 	/** Flag indicating whether this locale is actually using a locale for
126 	 * LC_NUMERIC (1), or if it should use the C default instead (0). */
127 	int using_numeric_locale;
128 	/** Flag indicating whether this locale is actually using a locale for
129 	 * LC_TIME (1), or if it should use the C default instead (0). */
130 	int using_time_locale;
131 	/** Flag indicating whether this locale is actually using a locale for
132 	 * LC_MESSAGES (1), or if it should use the C default instead (0). */
133 	int using_messages_locale;
134 	/** The structure to be returned from localeconv_l() for this locale. */
135 	struct lconv lconv;
136 	/** Buffer used by nl_langinfo_l() */
137 	char *csym;
138 };
139 
140 /**
141  * Increments the reference count of a reference-counted structure.
142  */
143 __attribute__((unused)) static void*
144 xlocale_retain(void *val)
145 {
146 	struct xlocale_refcounted *obj = val;
147 	atomic_add_long(&(obj->retain_count), 1);
148 	return (val);
149 }
150 /**
151  * Decrements the reference count of a reference-counted structure, freeing it
152  * if this is the last reference, calling its destructor if it has one.
153  */
154 __attribute__((unused)) static void
155 xlocale_release(void *val)
156 {
157 	struct xlocale_refcounted *obj = val;
158 	long count;
159 
160 	count = atomic_fetchadd_long(&(obj->retain_count), -1) - 1;
161 	if (count < 0 && obj->destructor != NULL)
162 		obj->destructor(obj);
163 }
164 
165 /**
166  * Load functions.  Each takes the name of a locale and a pointer to the data
167  * to be initialised as arguments.  Two special values are allowed for the
168  */
169 extern void* __collate_load(const char*, locale_t);
170 extern void* __ctype_load(const char*, locale_t);
171 extern void* __messages_load(const char*, locale_t);
172 extern void* __monetary_load(const char*, locale_t);
173 extern void* __numeric_load(const char*, locale_t);
174 extern void* __time_load(const char*, locale_t);
175 
176 extern struct _xlocale __xlocale_global_locale;
177 extern struct _xlocale __xlocale_C_locale;
178 
179 /**
180  * Caches the rune table in TLS for fast access.
181  */
182 void __set_thread_rune_locale(locale_t loc);
183 /**
184  * Flag indicating whether a per-thread locale has been set.  If no per-thread
185  * locale has ever been set, then we always use the global locale.
186  */
187 extern int __has_thread_locale;
188 #ifndef __NO_TLS
189 /**
190  * The per-thread locale.  Avoids the need to use pthread lookup functions when
191  * getting the per-thread locale.
192  */
193 extern _Thread_local locale_t __thread_locale;
194 
195 /**
196  * Returns the current locale for this thread, or the global locale if none is
197  * set.  The caller does not have to free the locale.  The return value from
198  * this call is not guaranteed to remain valid after the locale changes.  As
199  * such, this should only be called within libc functions.
200  */
201 static inline locale_t __get_locale(void)
202 {
203 
204 	if (!__has_thread_locale) {
205 		return (&__xlocale_global_locale);
206 	}
207 	return (__thread_locale ? __thread_locale : &__xlocale_global_locale);
208 }
209 #else
210 locale_t __get_locale(void);
211 #endif
212 
213 /**
214  * Two magic values are allowed for locale_t objects.  NULL and -1.  This
215  * function maps those to the real locales that they represent.
216  */
217 static inline locale_t get_real_locale(locale_t locale)
218 {
219 	switch ((intptr_t)locale) {
220 		case 0: return (&__xlocale_C_locale);
221 		case -1: return (&__xlocale_global_locale);
222 		default: return (locale);
223 	}
224 }
225 
226 /**
227  * Replace a placeholder locale with the real global or thread-local locale_t.
228  */
229 #define FIX_LOCALE(l) (l = get_real_locale(l))
230 
231 #endif
232