locale.cpp revision 6035e6cc8317600c3100fdf1070890c3e42715a7 
1/*
2 * Copyright (C) 2008 The Android Open Source Project
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 *  * Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 *  * Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in
12 *    the documentation and/or other materials provided with the
13 *    distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
16 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
17 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
18 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
19 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
21 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
22 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
23 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
24 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
25 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28
29#include <locale.h>
30#include <pthread.h>
31#include <stdlib.h>
32
33#include "private/bionic_macros.h"
34
35// We currently support a single locale, the "C" locale (also known as "POSIX").
36
37static bool __bionic_current_locale_is_utf8 = true;
38
39struct __locale_t {
40  size_t mb_cur_max;
41
42  __locale_t(size_t mb_cur_max) : mb_cur_max(mb_cur_max) {
43  }
44
45  __locale_t(const __locale_t* other) {
46    if (other == LC_GLOBAL_LOCALE) {
47      mb_cur_max = __bionic_current_locale_is_utf8 ? 4 : 1;
48    } else {
49      mb_cur_max = other->mb_cur_max;
50    }
51  }
52
53  DISALLOW_COPY_AND_ASSIGN(__locale_t);
54};
55
56static pthread_once_t g_locale_once = PTHREAD_ONCE_INIT;
57static lconv g_locale;
58
59// We don't use pthread_once for this so that we know when the resource (a TLS slot) will be taken.
60static pthread_key_t g_uselocale_key;
61__attribute__((constructor)) static void __bionic_tls_uselocale_key_init() {
62  pthread_key_create(&g_uselocale_key, NULL);
63}
64
65static void __locale_init() {
66  g_locale.decimal_point = const_cast<char*>(".");
67
68  char* not_available = const_cast<char*>("");
69  g_locale.thousands_sep = not_available;
70  g_locale.grouping = not_available;
71  g_locale.int_curr_symbol = not_available;
72  g_locale.currency_symbol = not_available;
73  g_locale.mon_decimal_point = not_available;
74  g_locale.mon_thousands_sep = not_available;
75  g_locale.mon_grouping = not_available;
76  g_locale.positive_sign = not_available;
77  g_locale.negative_sign = not_available;
78
79  g_locale.int_frac_digits = CHAR_MAX;
80  g_locale.frac_digits = CHAR_MAX;
81  g_locale.p_cs_precedes = CHAR_MAX;
82  g_locale.p_sep_by_space = CHAR_MAX;
83  g_locale.n_cs_precedes = CHAR_MAX;
84  g_locale.n_sep_by_space = CHAR_MAX;
85  g_locale.p_sign_posn = CHAR_MAX;
86  g_locale.n_sign_posn = CHAR_MAX;
87  g_locale.int_p_cs_precedes = CHAR_MAX;
88  g_locale.int_p_sep_by_space = CHAR_MAX;
89  g_locale.int_n_cs_precedes = CHAR_MAX;
90  g_locale.int_n_sep_by_space = CHAR_MAX;
91  g_locale.int_p_sign_posn = CHAR_MAX;
92  g_locale.int_n_sign_posn = CHAR_MAX;
93}
94
95size_t __mb_cur_max() {
96  locale_t l = reinterpret_cast<locale_t>(pthread_getspecific(g_uselocale_key));
97  if (l == nullptr || l == LC_GLOBAL_LOCALE) {
98    return __bionic_current_locale_is_utf8 ? 4 : 1;
99  } else {
100    return l->mb_cur_max;
101  }
102}
103
104static bool __is_supported_locale(const char* locale) {
105  return (strcmp(locale, "") == 0 ||
106          strcmp(locale, "C") == 0 ||
107          strcmp(locale, "C.UTF-8") == 0 ||
108          strcmp(locale, "en_US.UTF-8") == 0 ||
109          strcmp(locale, "POSIX") == 0);
110}
111
112lconv* localeconv() {
113  pthread_once(&g_locale_once, __locale_init);
114  return &g_locale;
115}
116
117locale_t duplocale(locale_t l) {
118  return new __locale_t(l);
119}
120
121void freelocale(locale_t l) {
122  delete l;
123}
124
125locale_t newlocale(int category_mask, const char* locale_name, locale_t /*base*/) {
126  // Is 'category_mask' valid?
127  if ((category_mask & ~LC_ALL_MASK) != 0) {
128    errno = EINVAL;
129    return NULL;
130  }
131
132  if (!__is_supported_locale(locale_name)) {
133    errno = ENOENT;
134    return NULL;
135  }
136
137  return new __locale_t(strstr(locale_name, "UTF-8") != NULL ? 4 : 1);
138}
139
140char* setlocale(int category, const char* locale_name) {
141  // Is 'category' valid?
142  if (category < LC_CTYPE || category > LC_IDENTIFICATION) {
143    errno = EINVAL;
144    return NULL;
145  }
146
147  // Caller wants to set the locale rather than just query?
148  if (locale_name != NULL) {
149    if (!__is_supported_locale(locale_name)) {
150      // We don't support this locale.
151      errno = ENOENT;
152      return NULL;
153    }
154    __bionic_current_locale_is_utf8 = (strstr(locale_name, "UTF-8") != NULL);
155  }
156
157  return const_cast<char*>(__bionic_current_locale_is_utf8 ? "C.UTF-8" : "C");
158}
159
160locale_t uselocale(locale_t new_locale) {
161  locale_t old_locale = static_cast<locale_t>(pthread_getspecific(g_uselocale_key));
162
163  // If this is the first call to uselocale(3) on this thread, we return LC_GLOBAL_LOCALE.
164  if (old_locale == NULL) {
165    old_locale = LC_GLOBAL_LOCALE;
166  }
167
168  if (new_locale != NULL) {
169    pthread_setspecific(g_uselocale_key, new_locale);
170  }
171
172  return old_locale;
173}
174